WETLANDS AND WATER QUALITY: EPA'S
RESEARCH AND MONITORING IMPLEMEN-
TATION PLAN FOR THE YEARS 1989 -
1994 a
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600389039
EPA/XXXXXXXXX
xxxxxxxx, 1989
WETLANDS AND WATER QUALITY:
EPA'S RESEARCH AND MONITORING IMPLEMENTATION PLAN
FOR THE YEARS 1989 - 1994
by
Paul R. Adamus
NSI Technology Services Corporation
200 SW 35th Street
Corvallis, Oregon 97333
Project Officer
Eric Preston
USEPA Wetlands Research Program
USEPA Environmental Research Lab
200 SW 35th Street
Corvallis, Oregon 97333
In cooperation with:
USEPA Office of Wetlands Protection,
Washington, D.C.
USEPA Environmental Research Laboratory,
Duluth, Minnesota
Roy F. Weston, Inc.,
Washington, D.C.
Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Corvallis, Oregon 97333
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DISCLAIMER/CREDITS ON CONTRACTS
This project has been funded by the United States Environmental
Protection Agency (EPA) and conducted at EPA's Research
Laboratory in Corvallis, Oregon, through contract 68-C8-0006 to
NSI Technology Services Corporation. It has been subjected to
the Agency's peer review and approved for publication.
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CONTENTS
1.0 Introduction 1
2.0 Plan Background 3
3.0 Institutional Basis for EPA Concerns 6
4.0 Unifying Principles and Strategy Choices
4.1 Principles 7
4.2 Strategies 8
4.2.1 Choices 8
4.2.2 Reasons for Favoring the Mesocosm
Approach 9
5.0 Research Components and Technical Approach
5.1 Water Quality Criteria to Protect Wetland Function
5.1.1 Rationale 13
5.1.2 Approach 15
5.1.3 Outputs 22
5.1.4 Potential Sources of Funding; Schedule.. 22
5.2 Wetlands Quality: Contamination Status of the
Wetland Resource
5.2.1 Rationale 26
5.2.2 Approach 27
5.2.3 Outputs 30
5.2.4 Potential Sources of Funding; Schedule.. 30
5.3 Waste Assimilation Limits of Wetlands
5.3.1 Rationale 33
5.3.2 Approach 38
5.3.3 Outputs 39
5.3.4 Potential Sources of Funding; Schedule.. 39
6.0 Literature Cited 43
APPENDIX A. Synopsis of the Survey Responses and the Easton
Workshop
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LIST OF TABLES
Table 1. Investigative techniques for biosurveys 18
Table 2. Major literature reviews and syntheses: 34
1. Effects of water quality on wetlands biota
2. Methods for sampling wetlands
3. Effects of wetlands on water quality
LIST OF FIGURES
Figure 1. Research workload model: Water quality standards
for wetlands 14
Figure 2. Schedule and needed budget ($K) for COMPONENT I:
Water Quality Criteria to Protect Wetland
Function 24
Figure 3. Existing long-term wetland data sets:
Preliminary inventory of freshwater sites 29
Figure 4. Schedule and needed budget ($K) for
COMPONENT II. Ecological Status of the Wetland
Resource 32
Figure 5. Schedule and needed budget ($K) for
COMPONENT III. Waste Assimilation Limits of
Wetlands 41
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ABSTRACT
EPA wishes to assure, through its research and monitoring
efforts, that existing surface water quality criteria are
adequate for protecting the chemical, hydrological, and
biological integrity of the wetland resource. The Agency wishes
to develop technical information to support designation of
particular wetlands for certain "uses" (e.g., wildlife
production, aquaculture). The Agency also wishes to estimate the
limits of different wetland types, both constructed and natural,
for intentionally or passively assimilating nutrients and
contaminants.
To accomplish these objectives, this plan proposes that EPA (a)
identify, from the existing knowledge base, specific substances
likely to exhibit enhanced mobility and toxicity in the unique
physicochemical environments which typify wetlands; (b) initiate
funding agreements with researchers to perform experimental
dosing of wetlands with these identified substances, for the
purpose of defining wetland response and identifying the most
sensitive community metrics; (c) develop and refine cost-
effective procedures for rapidly monitoring wetland integrity,
and quantifying the uncertainties associated with such
measurements; (d) implement a broad-scale network of long-term
wetland monitoring sites, to be used to define regionally
expectable levels for certain community metrics; (e) compile and
empirically analyze existing, landscape-level data sets with
regard to the effects of wetlands on regional water quality; and
(f) integrate the efforts by the iterative use of predictive,
quantitative models having minimal data input requirements.
These tasks will be tightly integrated to the degree that
institutional considerations and funding allow. The effort win
be closely coordinated with related efforts of other agencies and
institutions. Serious consideration will be given to using
existing research sites if these sites meet criteria for
statistical representativeness.
Implementation of this effort cannot occur without modest
increases in current research and monitoring budgets. If fully
funded, the above effort should provide EPA, within 6 years, with
a capacity to determine (a) whether existing criteria for surface
waters are adequate for protecting wetlands and their functions,
(b) whether wetlands regulation is succeeding, and (c) quantified
limits for use of wetlands as purifiers of water, particularly
with regard to their effectiveness in passively treating nonpoint
runoff. With no increase in current funding, the ongoing Wetland
Research Program is capable in the next 6 years of addressing
only the last of these objectives, for a single wetland region or
type.
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Sites were included if the same ecological measurements were made
(or are funded to be made) at least once every 3 years at exactly
the same location. The EPA Wetlands Research Program has ongoing
efforts to update this map (see p. 31) and appreciates hearing of
locations not shown. Abbreviations: CE (U.S. Army Corps of
Engineers); LTER (Long Term Ecological Research, funded by
National Science Foundation); NPS (National Park Service); USGS
(U.S. Geological Survey); DOD (U.S. Department of Defense); DOE
(U.S. Department of Energy); WDOE (Washington Department of
Ecology).
1.
Everglades (NPS)
19,20,21. 111.- Miss. R. LTER
2.
Apalachicola (U.FL, USGS)
22.
N. Temperate Lakes LTER
3.
Okeefenokee (U.GA)
23.
Cedar Creek LTER
4.
Buttermilk Sound (CE)
24.
Cottonwood Lake (USGS)
5.
Savannah River (DOE)
25.
Konza LTER
6.
North Inlet LTER (NSF, U.SC)
26 .
Bolivar Peninsula (CE)
7.
Coweeta LTER
27.
Jornada LTER
8.
Dismal Swamp (USGS)
28.
Niwot Ridge LTER
9.
Windmill Point (CE)
29.
Central Plains LTER
10.
Virginia Barrier Is. LTER
30.
Miller Sands (CE)
11.
Nott Island (CE)
31.
S. San Francisco Bay (CE)
12.
Niering wetland (Conn. Col.)
32.
King County (WDOE)
13.
Hubbard Brook LTER
33.
Nebraska Sandhills (USGS)
14.
Houghton Lake (U.Michigan)
34.
ELF study (USDOD)
15 .
Kellogg LTER
35.
Rhode R. (Smithsonian)
16.
Des Plaines mesocosm
36.
Creeping Swamp (USGS)
17.
Monroe Lake (U. Indiana)
18.
Cache River (CE)
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1.0 INTRODUCTION
This document describes products which the USEPA Wetlands
Research Program proposes to develop during the years 1989-1994.
The general protocols used to develop these products are also
described. All these products are intended to address concerns
about wetlands and water quality, and are part of a larger set of
products EPA is developing to deal with other aspects of
wetlands.
The need for a coordinated research program on wetlands and water
quality was highlighted most recently in the report of the
Wetlands Forum, a group convened at the request of the EPA
Administrator and representing industry, environmental, and
governmental interests. The Forum (p. 46, The Conservation
Foundation, 1988) recommended that:
"EPA and the state water pollution control agencies
review the implementation of their water quality
programs to ensure that they are offering adequate
protection to the chemical integrity of wetlands."
EPA's concerns about wetlands and water quality can be generally
categorized as follows:
I. Water Quality Criteria to Protect Wetland Function
II. Ecological Status of the Wetland Resource
III. Waste Assimilation Limits of Wetlands
These concerns are highly interrelated. The ability of some
types of wetlands to assimilate wastes (III) is well-documented.
However, while assimilating wastes, wetlands may be losing some
of their other functions, particularly those related to life
support. Existing criteria need to be examined with regard to
their ability to protect all potential wetland functions (I), and
the geographic extent of functional losses that are occurring
through contamination must be documented (II).
The specific products EPA would prepare include technical reports
that address the following questions for a portion of the wetland
types that exist in North America:
I. Water Quality Criteria to Protect Wetland Function
o Can technically sufficient and reproducible narrative
standards be developed to protect wetland integrity, or are
numeric standards essential as well?
o What are the best indicators of water quality condition?
o At what thresholds do these indicators suggest changes in
wetland integrity?
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o What are appropriate buffer widths for protecting wetland
integrity, given various scenarios?
o Where in a wetland should the most revealing samples be
collected?
o When and how should samples be collected, and what is the
expected variability?
II. Ecological Status of the Wetland Resource
o What are the regional background levels of the indicators?
o What percent of the region's wetlands exceed background?
o Do prevailing background levels fully support wetland
ecological integrity?
o What percent of the region's wetlands exceed criteria
recommended for protecting ecological integrity?
Ill. Waste Assimilation Limits of Wetlands
o What transformation rates for nutrients (nitrogen and
phosphorus), metals, and synthetic organics can be expected
under various combinations of vegetation type, sediment
type, loading rate, duration of exposure (age) and detention
time?
o Consequently, what loading levels can be assimilated over
the long-term? Can the ecological integrity and
assimilative capacity of a heavily loaded wetland recover
after a "resting period"? What determines how long this
period should be?
o In what situations is aluminum a valid predictor of
long-term phosphorus retention?
o Are there soil characteristics or observable landscape
features which correlate with high sediment aluminum?
o Are there soil characteristics or observable landscape
features which correlate with high denitrification rates?
o Are there soil characteristics or observable landscape
features which correlate with high rates of long-term
detention for selected metals and synthetic organics?
Technical and policy reasons for examining these particular
topics are described later in this plan (in section 5.0).
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2.0 PLAN BACKGROUND
EPA currently has a Wetlands Research Program based on the
Administrator's approval of a formal Research Plan (Zedler and
Kentula 1986). One of three components of the Plan, which covers
the period 1986-1990, concerns the effects of wetlands on water
quality. In 1987, the EPA Corvallis Environmental Research Lab
(Corvallis-ERL) was requested by the EPA Office of Wetlands
Protection to prepare a conceptually expanded version of this
Plan dealing specifically with the water quality component. The
present document represents that expanded version, and is
designated a Research Implementation Plan.
Factors responsible for initiating this new planning effort
include the following:
o increased concern that degradation of the nation's wetland
resource was not being fully accounted for by figures that
expressed losses solely in terms of acreage.
o A related concern about the adequacy of existing surface
water quality criteria to protect wetlands, a concern that
the original (1986) research plan was not intended to
address.
o A growing awareness that existing surface water criteria may
be unrealistic when applied to some wetlands which, due only
to natural factors, exceed some of these criteria, e.g., for
oxygen.
o Increased recognition of uncertainties regarding the
national extent of wetland contamination and its
consequences.
o Increased administrative interest in the use of wetlands as
a low-cost alternative to wastewater treatment plants, and
especially as de facto treatment for nonpoint runoff and
stormwater treatment.
o An increased committment to assuring that needs of the users
are carefully considered at every point in the development
of research products, and that the research results are
effectively transferred to the users (i.e., USEPA and state
personnel responsible for implementing sections 401 and 404
of the Clean Water Act).
o The need for a plan which describes in more specific terms
the actual research protocols to be used, i.e., an
Implementation Plan, rather than being limited to a general
discussion of the objectives, concepts, and protocols.
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The 1986 Plan has the following goals for water quality research:
"To quantify the water quality functions of wetlands;
to model the aggregated role of wetlands in altering
the quality of water in receiving water (at the
wetland, watershed, and ecoregion scale); to design
simple decision criteria for evaluation of water
quality functions, and to assess the effects of
cumulative wetland losses on the quality of water in
receiving water (at the wetland, watershed, and
ecoregion scale)."
More specifically, the effort described in the 1986 Plan was to
focus on three areas:
1. Quantification of rate functions for the retention or
transformation of organic chemicals, heavy metals and
nutrients;
2. Quantification of interactions among these substances
and their impacts upon wetland water quality function; and
3. Preparation of simple models or criteria for determining
which wetlands are effective assimilators of wastes.
The Plan emphasized the use of artificial "mesocosms" in
conjunction with in situ field experiments and the modification
of existing EPA hydrological simulation models. Mesocosms are
confined portions of wetlands, either natural or constructed,
which approximate the structure (both physical and biological)
and function of the larger wetland of which they are a part, and
which can be experimentally manipulated (e.g. , dosed with known
levels of chemicals, voided of particular organisms, isolated
from specific influences). Mesocosm implies greater size {on the
scale of several square meters) than microcosm, although these
are relative terms.
To date, the modeling and field experimentation efforts of the
1985 Plan have been partially implemented through the EPA-Athens
Environmental Research Lab. Mesocosm work has not begun and the
recommended work on retention/transformation rates has been
limited to nutrients. The work on organic chemicals, heavy
metals, and their interactions was not approved for
implementation due to budget constraints and Agency priorities at
the time.
The current effort to prepare a Research Implementation Plan has
had two major components:
o Survey of Experts. In June 1988, the Center for Wetlands at
the University of Florida invited over 200 scientists to
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respond to selected questions contained in a longer
documentwhich comprehensively considered the wetlands/water
quality issue. The survey format and analysis protocols
were designed by the firm of Roy F. Weston, Inc. The
technical content was developed jointly by the University of
Florida Center for Wetlands, the EPA Wetlands Research
Program, and a panel of independent scientists. Scientists
who were contacted represented a broad spectrum of sub-
disciplines, including toxicology, remote sensing,
hydrology, geochemistry, biology, and statistical design.
The overall response rate was about 25%. Results are
described in Appendix A.
o Workshop. In August 1988 some 40 scientists attended a
workshop in Easton, Maryland, to focus on specific research
priorities and protocols. The results of the above-noted
survey were used as a springboard for small-group
discussions, in an effort to derive a consensus opinion. A
detailed workshop summary is provided in Appendix A. In
general, the participants urged EPA to place greater
emphasis on estimating the sensitivity and resilience of
different wetland types, and as a precursor, EPA was urged
to determine which taxa, processes, or measurements best
indicate wetland integrity.
Following the Workshop, a Draft Implementation Plan was prepared.
Although prepared by Corvallis-ERL, this was a cooperative effort
involving wetland scientists from the EPA Duluth Environmental
Research Lab (Duluth-ERL) and Roy F. Weston, Inc. The Plan was
circulated for peer review to all workshop participants and
others who offered to review it.
Although the overall intent was to make the Implementation Plan
as congruent as possible with the general concepts outlined in
the 1986 Plan (as well as a 1988 internal EPA proposal,
"Ecosynthesis: Inland Wetlands Research and Monitoring Plan,
1990-2000), all water quality aspects were re-opened for
discussion. This Implementation Plan is also intended to be
consistent with:
o the EPA Task Force on Wastewater Discharge to Wetlands,
coordinated by the EPA Office of Federal Activities (1987)
o the EPA Office of Water's "Draft Framework for the Water
Quality Standards Program" (USEPA 1988).
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3.0 INSTITUTIONAL BASIS FOR EPA CONCERNS
EPA has a number of direct and indirect legislative mandates for
wetland protection and research, and many of these relate
directly to water quality issues.
The users of the outputs from a wetlands/water quality research
program would likely be the wetland program coordinators in
federal, state, and local agencies. Uses of the research outputs
might include the following:
o Determining what stipulations to include in a permit (e.g.,
permits under sections 401 and 404 of the Clean Water Act,
and involving NPDES activities and wetland dredge and fill)
for discharges or for minimum stream flow (water rights
issues) and other hydrologic needs of wetlands;
o Providing technical guidance for nonpoint source control
programs (sections 301 and 319 of the Clean Water Act);
o Measuring the effectiveness of existing laws to protect
water quality, and suggesting changes as needed;
0 Supporting a biophysical categorization scheme which would
result in the primary use of certain kinds of wetlands being
"water purification" (i.e., use designations);
o Recommending designs for created wetlands which would
maximize their ability to purify wastewater while sustaining
their ecological values;
o Recommending screening criteria for purchase (e.g., under
section 318) of wetlands potentially useful for wastewater
treatment;
o Assisting in the design of remedial actions for Superfund
sites which will not destroy important wetland functions;
o Establishing EPA's national policy regarding use of certain
wetlands for point/nonpoint effluents.
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4.0 UNIFYING PRINCIPLES and STRATEGY CHOICES
Before describing the specifics of the proposed plan, certain
unifying principles and choices of research strategy will be
briefly noted. These principles and strategies apply not just to
particular components of the plan, but to the plan as a whole.
They are critical to the plan's success, and an attempt will be
made to integrate them with specific protocols at every step of
the plan's implementation.
4.1 Principles
EPA research on wetlands and water quality should be:
o Clearly defined, with the connections among different
projects, using different methods, in different regions and
states being well-explained.
o Long-term, because wetlands are extremely dynamic and
complex systems. What is true during one season or year is
often not representative, and natural climatic variability
may induce changes as great as that from some anthropogenic
stressors. Moreover, the symptoms of excessive loading may
not appear for several years, but nonetheless may be
catastrophic.
o Interdisciplinary, because the influences of hydrology,
geochemistry, and biota are intricately intertwined.
o Integrated at several levels, e.g., models and data; basic
and applied approaches; laboratory and field data;
structural and functional information. In all these
examples, a feedback mechanism must exist so the activities
are mutually beneficial and result in greater predictive
power.
o Hierarchical, because effects occur at the level of the
individual organism, the population, and the community.
o Multi-Scaled, because effects may be detectable only at the
level of the region, watershed, wetland, or microsite.
o Stratified, by wetland functional type and region, because
water quality processes and indicators are thought to be
extremely variable from region to region and type to type.
With a limited budget, every opportunity must be sought to
generalize from a few studies to the whole resource.
o Coordinated with other similar efforts, both within EPA,
with other Federal and State agencies, and with private
institutions.
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o With uncertainty clearly measured and articulated, so that
results can be appropriately extrapolated to other regions
and wetland types.
o With users involved in transfer of the results, so that the
research provides EPA with more than just an elegant
understanding of a technical process.
4.2 Strategies
4.2.1 Choices
Regardless of which of the water quality components (I, II, III-
- see Introduction) are being addressed, basic decisions must be
made regarding the relative emphasis to be placed on:
o particular regions or wetland types;
o defining relationships from empirical analysis of spatially
extensive data (Peters 1986) as opposed to defining these
through development of mechanistic models or manipulative
mesocosm experiments (as described earlier, mesocosms are
confined portions of wetlands which approximate the physical
and biological structure and function of the larger wetland
of which they are a part, and which can be experimentally
manipulated);
o intensive vs. extensive study designs, e.g., whether EPA
obtains a better ability to extrapolate to the nation by
studying just a few wetlands constantly and with
sophisticated methods for many years, or studying more
wetlands with less detailed methods or for shorter time
periods.
Under ideal fiscal circumstances, these difficult choices would
be unnecessary. Mathematical models would be developed and used
to guide the research, and would provide a format for presenting
the research results. Results of the exploratory statistical
analyses associated with "real-world" empirical studies would be
used to formulate hypotheses for testing in the more artificial
environment of manipulative mesocosm experiments. Coefficients
from both the empirical and manipulative studies would be used to
calibrate and fine-tune the models. Intensive studies would be
conducted at a few sites representing a subset of an extensive
network of monitoring sites, so that the temporal, spatial, and
procedural limitations of data from the extensive network become
known.
Because EPA, even in combination with the efforts of other
agencies, does not have the resources to approach this ideal,
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choices must be made. With regard to research, this plan
recommends that EPA emphasize the use of manipulative mesocosm
experiments, at the possible expense of fully-implemented
empirical and modeling efforts, to address the three key
components of the water quality effort. With regard to
monitoring, this plan recommends that efforts be devoted to
intensive, long-term measurements unless allocated resources (on
the order of $10K to $50K per site) are of sufficient magnitude
to allow for extensive monitoring as well. In both instances
(i.e., research and monitoring), the empirical and survey
approaches, and deterministic modeling, should continue to have a
role, but should be subordinate to the favored approaches.
Regardless of the approach chosen or the water quality issue, the
cost-effectiveness of the research will be greatest if it focuses
on the most important water quality stressors in priority wetland
types and regions, particularly if this can involve building upon
ongoing studies in the priority regions.
At the workshop, participants considered metals and synthetic
organics to be of greatest concern in terms of their effects on
wetlands, while nutrients and sediment were most important with
regard to the converse—the effects of wetlands on receiving
water quality. The most severe and extensive wetland stressor in
many regions was considered to be nonpoint runoff. Activities
that were viewed with greatest concern (based on their extent and
severity of impact to wetland water quality) were considered to
be agricultural and forestry runoff, domestic/industrial wastes,
effluents from land clearing, land drainage, irrigation,
dike/levee installation, and channelization. Again, it was noted
that the relative importance of these varies greatly by region
and wetland type, and research will be most cost-effective if it
can be focused accordingly.
For the purpose of establishing priorities, geographic or
ecoregional descriptors (e.g., New England, the Southeast) can be
merged with wetland type descriptors from the Cowardin
classification system to define wetland "region-types" (e.g.,
Southeast forested nontidal = bottomland hardwood wetlands).
Climate, wetland contiguity, and other landscape conditions may
be used to refine this categorization scheme, whose sole purpose
is to consolidate the regions and wetland types in order to
facilitate priority-setting. At the workshop, the. following
region-types (in no order of priority) were suggested by various
participants as being relatively homogeneous and containing
wetlands most threatened by water quality impacts: bottomland
hardwoods, prairie potholes, western riparian, northeastern
forested palustrine, urban tidal.
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4.2.2 Reasons for Favoring the Mesocosm Approach
The recommendation for use of mesocosms is consistent with many
previous reviews, conferences, workshops and the prior EPA
Research Plan for wetlands (e.g., Nixon and Lee 1987, Bayne et
al. 1988, Zedler and Kentula 1986). Major advantages of
manipulated mesocosm systems include the greater ability to
control the independent variables of wetland hydrology (flow,
duration, degree of saturation or inundation, etc.) and loading
rates of water quality contaminants (dose levels). For example,
it may not be possible to control hydrology in natural wetlands
due to annual and longer-cycle (20 years or more) variation in
climate (van der Valk et al. 1988). With mesocosms, these
treatment conditions can be selected and maintained with greater
assurance than in unconfined natural wetlands.
Manipulation also provides greater commonality of general site
conditions (climate, substrate, biotic community species
composition) than may be easily obtained in empirical studies.
Likewise, they afford greater savings in the logistical resources
of data collection, when multiple manipulated systems are grouped
at one location. Uniform manipulated conditions and small scale
system definition also provide for replication of treatments
within one location. Systems can also be designed so that
sampling may be conducted over longer periods of time and with
less damage to the wetland under study (Zedler and Kentula 1986).
Formal cost comparisons have not been made between mesocosm and
empirical approaches, but it is believed that the mesocosm
approach's reduced costs for site screening, travel, and data
analysis (per dose-response relationship examined) will result in
greater savings.
Despite these advantages, many participants at the workshop
favored the empirical approach, partly because of its "real-
world" character. Every wetland located downstream of a
wastewater treatment facility or every headwater wetland
receiving agricultural runoff could be studied for its response
to water quality. In this perspective, a great range of
"experiments" are already underway all across the nation. All
that needs to be done is conduct the studies. However, the
resource and time requirements needed to conduct a series of
valid empirical studies may be beyond the means presently
available to the Wetland Research Program.
To illustrate, consider a situation where EPA desires to
categorize wetlands, for policy reasons, according to their
ability to sustain continued loadings of wastewater. To support
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such a categorization, comparable data would need to be collected
or synthesized regarding the following:
loading rates (5 different rates, for example)
detention times (5 different times)
years of operation (4 different ages)
sediment types (4 different types)
flow distributions (5 spatial configurations)
wetland types/regions (3 vegetation types)
Existing knowledge of wetlands indicates that it is unlikely that
a simpler framework (fewer variables and classes) would
adequately categorize wetlands for this purpose. Indeed, many
would argue that the above list should be longer to adequately
consider the complexity of wetlands. Perhaps what is desirable,
then, is to seek an understanding of levels of function
associated with broad wetland types, rather than seeking to
categorize all wetlands based on function.
If such a data collection effort were implemented, the number of
cases (wetlands) must be at least 2 to 5 times the number of
variables, which in this case is 6, in order to meet minimum
statistical criteria. A statistically better, factorial,
parametric approach requires that all possible combinations be
tested. This would require sampling in 6000 wetlands (5x5x4
x 4 x 5 x 3), not including replication.
Ideally, to generate data with maximum explanatory power, an
empirical study design also should be "orthogonal" and "balanced"
(Skalski and McKenzie 1982). An "orthogonal" design requires
that a level of a factor appears with approximately equal
frequency with all levels of another factor. For example, within
the factor "years of operation", each combination of detention
time and flow distribution present in the pre-loading period
(year 0) must also be present in each of the post-operational
periods. In order for a design to be "balanced", each unique
treatment combination should be replicated a nearly equal number
of times. Thus, the duration and intensity of sampling ideally
should be nearly equal during the pre- and post- loading periods.
Few empirical studies in ecology approach this ideal. Partly
because of this, the resultant multivariate equations, even if
they are at all statistically significant and explanatory of the
variance, usually cannot be applied in a predictive sense to
situations beyond those of the study area. Although
randomization and use of non-parametric procedures can soften
these requirements somewhat, the requirements of empirical
studies for unaffordable sample sizes remains a potential
barrier.
Another difficulty encountered in analyzing data from a set of
wetlands which have encountered various degrees of anthropogenic
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stress is that critical historic information on the hydrology of
all wetlands in the set is typically lacking. Often, such
empirical studies become experiments with inadequate pre-
treatment data. A solution is to use wetland creation projects
as a pre-treatment case, but (a) the ability of created wetlands
to simulate natural wetlands remains debatable, thus limiting the
applicability of conclusions just to the set of created wetlands,
and (b) conclusions from such studies would not become available
for many years. Although this plan proposes an integrated
approach involving mesocosms, empirical studies, and literature
syntheses, if such an approach turns out to be financially
prohibitive, the mesocosm approach would be preferable to using
the others alone.
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5.0 RESEARCH COMPONENTS AND TECHNICAL APPROACH
As noted in the Introduction, the Water Quality/Wetlands issue
has three major interrelated components:
I. Water Quality Criteria to Protect wetland Function
II. Ecological Status of the Wetland Resource
III. Waste Assimilation Limits of Wetlands
In the remainder of this plan, we describe the procedures that
would be used to implement the objectives of each component. The
manner in which the tasks and components are interrelated, and
their relationship to program goals, is shown in Figure 1.
5.l Water Quality Criteria to Protect Wetland Function
5.1.1 Rationale
The process of developing water quality criteria for wetlands
poses a fresh opportunity for avoiding some of the pitfalls of
previous approaches applied to non-wetland surface waters (e.g.,
see Karr 1981, USEPA 1987, Ongley et al. 1988). These criticisms
include:
o There are hundreds of obscure chemicals whose toxicity is
mostly unknown, and the cost of testing the effects of all
of these would be astronomical.
o Efforts to monitor chemical concentrations in the
environment often miss episodic events when greatest
concentrations or exposures occur.
o The resources which are to be protected are partly
biological, whereas monitoring programs typically focus on
chemical measurements which purportedly are linked to
biological conditions;
o There are hundreds of species and life stages whose long-
term, sublethal sensitivity to contaminants is unknown, and
the cost of testing for effects on these would be extreme;
o Even where surface concentrations and potential toxicity are
known, the actual exposure of sediment-dwelling biota and
trophically higher consumers to the contaminants may not be,
due to behavioral and other factors.
o The antagonistic toxicities of chemicals and physical
stresses are mostly unknown, particularly the cumulatively
stressful combinations of hydroperiod alteration, toxicants,
and excessive nutrients.
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Figure 1. Resecrcr, Workload Mode!: State Wcter Quality Standards for Wetlands
* Cumulative Efiects is en independent element of EPA's Wetlands Research Procrcm
IWoste
I assimilative
! capacity
|(WQ PI 5.3)
j Determine how much of
j a selected pollutant
i a wetland can ossimilote
land what influences
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exDeriments
I
Identify the most
ossimilative types of
wetlands, ond limits
I Water cuciity
Icriteric
I development
| (WQ PI 5.1)
, Determine which pollutants
; ploce wetiands ot greatest
: risk, isolate woter quality
i criteria suitable for both
i surfoce waters and wetlonds
1
Develop testinc protocols.
Identify pollutant
indicators ond the bes!
woy to monitor them
Test priority pollutants
experimentally using
mesocosms to simulote
various scenarios
iWetlcnd
Icontaminont
| monitoring
| (WQ Pi 5.2)
| Compile and review j
existing dato on wetland
contamination. Identify
contamination indicators
JL
Establish stotewide
pilot monitoring oroiect
io test indicators of
contamination stotus.
Follow with full
implementation of
regional monitoring net
Define expected
range of conditions,
for criterio development
| Cumulative '
i effects i
studies » i
Exomine the regional
effects of wetlands on
| water quality, hydrology
and biological resources
j Analyze existing
; regional date sets to
j identify wetland
I types/patterns that
I effectively assimilate
j pollutants
Refine the synoptic
method ond use to
classify priority ond
high risk wetlonds
biological/chemical
criteria
(norrative ond numeric)
use
classification
WATER QUALITY STANDARDS FOR WETLANDS
antidearadation policy &
the designation of
outstanding state
resource waters
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15
EPA has responded to these concerns by modifying some of its
ecotoxicological procedures (e.g., see "Philosophy of Criteria"
in Appendix C of USEPA 1986). Still, there are additional
technical concerns about the wisdom of applying criteria intended
for surface waters to wetlands. Wetlands frequently have lower
(and more spatially variable) pH, lower dissolved oxygen, extreme
reducing conditions, more potential for photodegradation and
biodegradation, greater potential for chelation and organic
complexation, and higher sulfide concentrations than do surface
waters generally. Under certain circumstances any of these
conditions can profoundly affect the rate and direction of
contaminant cycling in wetlands-, as well as the bioavailability
of contaminants. Moreover, wetlands are distinguished by their
exceptional concentrations of aquatic life, heightening concerns
about the potential for bi©accumulation and ultimate loss of the
life support function. Yet, existing ecotoxicological protocols
have not involved the testing of typical wetland species under
background physicochemical conditions which typify wetlands, so
the validity of applying existing surface water criteria to
wetlands is unknown. Moreover, the indicators of ecological
integrity in wetlands, unlike the situation with quality
indicators in other surface waters, are unlikely to be synonymous
in concept with concentration levels of contaminants.
5.1.2 Approach
In considering the adequacy of existing criteria, a fundamental
question is, "What should EPA be trying to protect?"
Participants at the workshop responded by describing the target
as "wetland integrity," which was defined as follows:
" the persistence of physical, chemical, and biological
conditions which sustain the long-term processes and
structure of the regional wetland resource."
The effort should then progress as follows:
Task l. Examine chemical mobility effects specific to "wetland"
envi ronments.
Through literature review and interviews with key scientists,
available information on the probable effect of the "wetland"
characteristics (e.g., organic matter concentrations, others
listed above) on the cycling and bioavailability of EPA priority
pollutants would be compiled. If funded, this effort would be
conducted by the Duluth ERL. The result could be a ranking of
pollutants of most concern in wetlands because of their mobility
characteristics. Recognizing the paucity of data to support such
a ranking, its purpose will be to focus research, rather than
stimulate regulation in a particular area.
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16
Task 2. Consider the potential toxicity of mobile contaminants.
The mobility-based ranking of pollutants described above could be
compared with a classification of contaminants based on their
ecotoxicity and bioaccumulation potential, and probability of
wildlife exposure. A preliminary ranking of this type was
recently developed by the U.S. Fish and Wildlife Service (USFWS).
Task 3. Prioritize contaminants for further testing.
The Wetlands Research Program may suggest that chemicals which
appear on both lists receive priority for ecotoxicological
testing under wetland-like conditions.
One objective of such testing would be to determine if the
sensitivities of selected wetland organisms to such chemicals are
analogous to the sensitivities of organisms typically employed
for toxicological testing (e.g., fathead minnow, rat). The
selection of wetland species for this calibration effort would be
based in part on initial results from ongoing field studies in
Minnesota, and later on the data from mesocosm studies in other
wetland types.
The other objective would be to determine if the effect of
stereotypical "wetland" conditions on published cycling rates is
significant enough to warrant modifications of the existing
surface water criteria. These efforts would be coordinated with
EPA efforts aimed at developing quality criteria for sediment
environments.
The EPA Wetlands Research Program does not currently have the
resources or mandate to conduct extensive laboratory bioassay
testing. However, other branches of EPA and the USFWS are
actively engaged in such testing, and the Research Program,
acting through EPA's Office of Wetlands Protection, will seek to
become involved in the design and review of such studies.
Task 4. Employ mesocosms to refine field monitoring and data
reduction protocols.
There appeared to be a consensus of workshop participants that
EPA, before or during its implementation of expanded
ecotoxicological and geochemical studies, should determine how
field monitoring data could later be compared with existing,
traditionally-derived, laboratory bioassay data to judge "wetland
integrity." The participants saw great potential value in the
use of indicator taxa and processes for measuring wetland
integrity, but only after (a) replicable protocols are refined
for monitoring these and presenting their data in a meaningful
format, and (b) toxicity data become available from manipulative
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17
experiments.
However, field monitoring and data presentation protocols for
wetland communities were felt to be still in a largely
developmental stage, with regard to actually linking specific
metrics to wetland integrity. Thus, refinement is needed before
wetland protocols can be used to adequately assess the
effectiveness of water quality criteria for protecting wetland
function.
Mesocosm studies (dose-response manipulation of confined natural
systems) are a relatively cost-effective way of identifying the
best indicators of wetland integrity. Particular monitoring
protocols would be examined first in mesocosms, by dosing
confined parts of wetlands with known concentrations of
prioritized contaminants, and then comparing the relative
abilities of different monitoring methods and metrics for
detecting expected change in concentrations, taxa, and processes.
A similar sensitivity analysis using marine mesocosms was
recently conducted and summarized by Bayne et al. (1988). That
team of researchers recommended use of dose-response curves based
on community-level metrics. Some of their data reduction
techniques are listed in Table l. They also examined the cost-
effectiveness and sensitivity thresholds of alternative
monitoring protocols. Elements of statistical design for aquatic
mesocosms are addressed by Clark and Green (1988).
The mesocosms themselves could be situated in either natural or
created wetlands. Although created wetlands may be easier to
manipulate and usually have a known history, a concern exists
that data are as yet inadequate to demonstrate that they are
sufficiently similar to natural wetlands, at least in the context
of mitigation policy decisions, to be considered the same.
Consequently, there are concerns about the ramifications of
extrapolating the results of mesocosm research conducted in
created wetlands to natural systems.
Regardless of where the mesocosms are located, a few design or
selection elements are important (Giesy 1980, Bayne et al. 1988,
van der Valk et al. 1988). In considering unit size, mesocosms
would be as large as feasible, in order to encompass the
variation found in the natural wetland and to avoid both edge and
sampling effects. This may be important when considering the
size of vegetation patches or habitat of important animal
species. Small system size is more subject to cumulative
disturbances, and lack of normal exchange with adjoining surface
and ground waters can lead to large growths of periphyton and
other aberrations (Schindler 1987), particularly for experiments
of longer duration.
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TABLE 1. Investigative Techniques for Biosurveys (Bayne et ai
1988)
Multivariate Methods
Classification:
Hierarchical agglomerative clustering based on
group-averaging of Bray-Curtis similarity measures.
Ordination:
Multidimensional scaling, detrended correspondence analysis
principal components analysis and reciprocal averaging.
Discrimination tests:
Analysis of similarity, Roy's greatest root criterion and
Malhanobis' distance tests, plus canonical discriminant
analysis.
Univariate Methods
Comparative, or with reference samples:
Number of taxa (S), total abundance (A), total biomass (B)
abundance ratio (A/S), size ratio (B/A), abundance and
biomass group distributions, dominance distributions,
diversity and evenness indices, comparison of functional
groups, biomass spectra.
Single sites without reference samples:
Identification of indicator organisms, abundance/biomass
comparison curves (ABC).
Correlating community metrics with pollution levels
Visual pattern analysis of mapped, separated factors, metrics
and pollution levels.
Establishing pollution-community, cause-effect relations
Mesocosm studies.
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19
The scale of the manipulated system units could range from very
small, short term, bag enclosures to entire wetlands. This would
depend mostly on the type-region of wetland under study.
Forested wetlands would need to be investigated through
subdivision of natural wetlands, while emergent systems may be
addressed partly by use of bag enclosures (Zedler and Kentula
1986, and Herron 1985). What remains most important is the
representativeness of the unit design to the wetland type-region
under study.
Studies using subdivision of natural wetlands would be required
to investigate wetland qualities which may not be developed in
created or artificial wetlands. This would be particularly
evident when investigating properties related to soil structure,
such as the relation suggested between the level of extractable
aluminum and long-term phosphorus retention. Subdivision
isolation of a uniform wetland type area through berms, dikes or
other barriers would seem appropriate for many wetland types (van
der Valk et al. 1988, Herron 1985), but may be unwarranted due to
cost, sampling or the dynamics of the key wetland processes under
investigation. A critical consideration is representation of the
hydrologic pattern, which drives the processes and function of
the particular wetland type.
In summary, EPA's decision on where to locate the mesocosm
experiments should be based on several factors, including the
following:
o representativeness of the site;
o ability to control and measure inputs and outputs;
o presence of existing control works (for economic
reasons) which appear to have had minimal impact on the
naturalness of the site;
o existence of long-term, interdisciplinary, baseline
data on the site;
o proximity to qualified research scientists and
opportunities for cooperative efforts.
EPA's effort might parallel the mesocosm effort of Bayne et
al.(1987), and address the following similar questions:
o Where in a wetland should the most revealing samples be
collected?
o When and how should samples be collected?
o What is the expected variability?
o What are the best indicators (taxa or processes, and their
related metrics) of wetland water quality?
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20
o At what thresholds do these indicators suggest changes in
wetland integrity?
As part of the present planning effort, the Corvallis-ERL has
developed a list of potential indicators and community metrics
for wetlands. This list also describes the known advantages and
disadvantages/limitations of each, particularly with regard to
the influence that wetland type and contaminant type have on
their applicability. This material was distributed at the
workshop as a springboard for discussion.
Workshop participants felt that data are insufficient to suggest
that either processes (function) or taxa (structure) are better
indicators of anthropogenic Hater quality stress in wetlands.
Survey respondants urged that both be measured if possible, and
that the potential for correlations be examined in different
wetland type-regions. A recent workshop addressing similar
issues using marine mesocosms (Warwick 1988, Bayne et al. 1988)
concluded that multivariate and graphical methods of description
and testing were preferred, since they are more sensitive than
diversity indices. Studies in lake mesocosms (Schindler 1987)
have indicated the sensitivity of species dominance and life-
table methods of data reduction, as opposed to measurements of
ecosystem processes, for detecting contamination. However, the
data requirements for use of life-table methods would probably be
too severe to allow their use as a routine tool throughout an
extensive network of monitoring sites, so results of this
approach should be correlated with simpler measurements on a
subset of monitored sites. A similar conclusion pertains to
sampling and chemical analyses of tissues.
With regard to structural measurements, participants saw
considerable need for documenting and regionalizing the Florida
criteria for wastewater effluent discharges to wetlands (see
Appendix A). Many believed that community metrics based on
certain invertebrate taxa, especially the less mobile species
(e.g., amphipods) have the greatest potential for forming the
basis of a wetland "index of biotic integrity (IBI)", similar in
concept to IBI's developed for other surface waters and primarily
using fish. However, such metrics must be used cautiously due to
the extreme temporal and spatial variability within wetlands, as
well as the potential for genetic adaptation to contaminants.
The response of wetland vegetation to contaminants was judged by
survey respondants to be too slow, too insensitive, and too
interrelated to other factors to serve, alone, as a practical
indicator of contaminants. However, vegetation is a very
sensitive indicator and integrator of hydrologic stresses, and
some species can be highly sensitive to particular contaminants.
Considerable support was shown for measuring hydroperiod
variation, sediment processes, and sediment chemistry as
reflections of long-term alterations of wetland integrity. No
wetland-focused, regional monitoring networks currently exist for
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21
these indicators, and considerable effort might need to be
focused on testing and developing their use as part of a rapid
assessment protocol.
In summary, the following features were believed to be most
important or promising as indicators of wetland integrity
overall, although priorities may shift by region and wetland
type:
POTENTIAL INDICATORS OF STRESSOR STATUS:
1. Hydroperiod, i.e., abnormal (compared to reference wetlands)
degrees and variability of the duration and frequency of
flooding.
2. Sediment and organic matter accretion.
3. Metals. Selection of specific ones would be dependent on our
analysis of expected exposure (geology, land use) and
bioaccumulation/toxicity potential. Likely exposure
scenarios could be generally identified using existing
source inventories (e.g., Resources for the Future database)
and noting likely source-receptor pathways.
4. Synthetic organics. Specific ones dependent on our analysis
of expected exposure and bioaccumulation/toxicity potential,
as above.
5. Nutrients. Ratio of organic to inorganic; ammonium,
nitrate, total nitrogen, total phosphorus, soluble reactive
phosphorus, phosphorus-sorption capacity.
6. Cofactors: Conductivity, temperature, pH, sediment organic
matter, oxygen demand, watershed characteristics. These
alone do not indicate stressor status, but are needed to
explore causality.
POTENTIAL INDICATORS OF ECOLOGICAL STATUS:
7. Vegetation. The selection of particular taxa and communities
would be dependent on the region and wetland type. Use of
remote sensing for monitoring would be emphasized.
8. Macroinvertebrates, particularly non-emergent ones
(crayfish, mollusks, amphipods). Addresses contamination
which may be less likely to be immediately sensed by
vegetation.
9. Waterbirds, at least those with expected high-sensitivity or
rarity. This indicator is included mainly because of
availability of national, long-term, comparison data sets
(USFWS Breeding Bird Survey and Christmas Bird Counts) and
because of its status as a socially-recognized assessment
endpoint.
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22
Task 5. Conduct a coarser-scale comparison of the monitoring
and data reduction protocols.
Any manipulated system, whether natural or artificial, should not
be used alone, but should be studied in conjunction with studies
in uncontrolled natural wetlands. A coordinated iteration of
manipulative and empirical studies is preferred, and would be
implemented to the extent that resources allow. Such an approach
utilizes the strengths of each approach, while ensuring the
representativeness of manipulated systems and paving the way
towards the larger goal of extrapolating study results to other
wetland types and regions.
In order to approach this objective and perfect the field
monitoring protocols, the mesocosm studies would be used to
complement the results from an ongoing, 2-year empirical analysis
of Minnesota wetlands, being conducted jointly by the Duluth ERL
and the Natural Resources Research Institute of the University of
Minnesota. This study of about 30 wetlands will partly address
monitoring issues that cannot be fully considered at the mesocosm
scale. The Corvallis ERL's experiences with field protocols for
comparing created wetlands with natural wetlands would also be
reviewed for their applicability; these procedures have already
been field-tested in 3 regions and been approved by EPA QA/QC
officials.
5.1.3 Outputs
Task 6. Produce Research Syntheses
The results of the mesocosm experiments and the already-initiated
empirical studies may be presented as peer-reviewed journal
papers or EPA reports. To whatever extent allowed by the data,
the results of the dose-response studies could be presented as
quantitative ecotoxicological models, and results from the
Minnesota field study might be presented as proposed regional
biological criteria for that study area. Results would be
presented in the context of related ongoing ecotoxicological work
performed by other agencies or divisions of EPA. Another
important output would be a tested field manual for wetland
monitoring, describing protocols appropriate to geographic and
budgetary situations similar to those encountered in our mesocosm
and limited empirical studies.
5.1.4 Potential Sources of Funding; Schedule
Potential Funding Sources
We estimate the proposed effort will require a total of $3.5
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23
million over the 6-year period. Funding for the first empirical
study (Minnesota wetlands) exists for FY89. However, funding
does not presently exist for most of the activities outlined
above.
1989 - 1994
Needed SK
Task 1. Mobility Literature Review 10
Task 2. Toxicity Cofactor Literature Review 20
Task 3. Selection of Candidate Indicators 20
Task 4. Dose-response Testing of Candidate
Indicators 2000(1)
Task 5. Empirical Field Studies of Candidate
Indicators 1250(2)
Task 6. Research Synthesis 200(3)
(1) Assumes testing of indicators in 5 mesocosms (experimental
wetland region-types)/ each test requiring 2 years, and costing
$200K per mesocosm per year to test the response of various
taxa/processes to stressors of greatest concern (probably 2 heavy
metals, nutrients, and a few synthetic organics). Assume a need
for proportionately greater funding if a wider variety of wetland
types and/or stressors are to be examined in the same period of
time.
(2) Assumes collection of regional field data in 5 region-types
(preferably same region as mesocosm), each collection occurring
in one year and costing $250K. The ability of 3-5 taxonomic/
process measures to indicate ecological integrity when presumably
exposed to particular stressors would be investigated, and
results compared to those from mesocosms.
(3) Involves literature review updates, development of simple
ecotoxicological models, research synthesis, interim progress
reports, publication of a wetlands field monitoring manual, and
technological information transfer.
Schedule
The schedule for the tasks described above is shown graphically
in Figure 2, and is presented narratively below. Again, note
that this schedule is contigent upon the specified full-funding
levels.
Fiscal Year 1989
The ongoing empirical studies in Minnesota will continue, and
preliminary results will be used to focus the design of the first
mesocosm study.
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24
Figure 2. Schedule and needed budget ($K) for COMPONENT I: Water
Quality Criteria to Protect Wetland Function
FY89
Task 1. Mobility Literature Review 10
Task 2. Toxicity Cofactor Literature Review 20
Task 3. Selection of Candidate Indicators 20
Task 4. Dose-response Testing of Candidate indicators:
FY:
M
1Q
11
12
wetland
type/region
1*
200
200
wetland
type/region
2*
200
200
wetland
type/region
3*
200
200
wetland
type/region
4*
200
200
wetland
type/region
5*
200
200
Task 5. Empirical Field Studies of Candidate Indicators of
Wetland Integrity
wetland
wetland
wetland
wetland
wetland
type/reg
type/reg
type/region 5*
FY:
on 1*
type/reg
type/region 2*
on 3*
on 4*
250
250
250
250
12
13
14
250
Task 6. Research Synthesis: 25 25 25 25 100
TOTAL $K, COMPONENT (I):
FY89
450
FY90
675
FY91
675
FY92
875
FY93
675
FY94
100
Region numbers are hypothetical and do not necessarily
correspond with EPA administrative regions.
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25
Fiscal Year 1990
Manipulative experiments would be concluded on the first wetland
type-region mesocosm, and a second mesocosm study would begin. The
Minnesota study will also conclude, with a report describing those
wetland variables most affected by wetland or watershed
disturbances- A second empirical study (building upon the
Minnesota one) would concurrently be implemented in the same
priority wetland type-region. This study would focus on a priority
stressor/activity, perhaps examining wetlands at sewage outfalls,
stormwater basins, Superfund sites, or intensive agricultural
runoff areas. Multivariate analyses will be used in an exploratory
manner to help discern which indicators most faithfully indicate
high loading rates and/or presumed contamination.
Fiscal Year 1991
Manipulative studies would be initiated in a third priority wetland
type-region, and would be concluded on the second. A third
empirical study would be initiated.
Fiscal Year 1992
Manipulative studies from the third mesocosm study would be
concluded, and a fourth mesocosm and empirical study initiated .
Fiscal Year 1993 - 1994
Mesocosm and empirical studies (all 5) would be concluded and a
synthesis of the results would be prepared.
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26
5.2 Wetlands Quality; Ecological Status of the Wetland Resource
5.2.1 Rationale
There is an increasing concern that degradation of the nation's
wetland resource is not being fully accounted for by figures that
express losses solely in terms of acreage. Stresses imposed by
heavy metals, synthetic organics, excessive nutrients and
sediment, and inadequate minimum flows (or other hydrologic
disruptions) may be seriously degrading the beneficial functions
of the wetland resource. However, while data on acreage trends
is being compiled by the U.S. Fish and Wildlife Service, the
extent of chemical degradation and its trend is not being widely
measured.
EPA does not have the resources to monitor vast numbers of
wetlands of all types in an attempt to determine the extent of
stress. Participants at the Easton workshop were emphatic in
recommending that EPA not divert its limited resources to a
national monitoring program unless adequate funds are allocated
for appropriately intensive studies of a significant portion of
the sites. This is the intent of the approach proposed in the
following section (5.2.2).
A national wetlands monitoring program would have two main
objectives:
o to quantify regionally expectable conditions of wetland
integrity, i.e., by examining levels of chemical substances,
community structure, and community function (using metrics
tested in Component I, above) in the most apparently
"pristine" wetlands in a region;
o to quantify changes over time in the set of monitored
wetlands, using the same metrics.
A number of states are implementing the first objective in
streams using macroinvertebrates or fish. For example, Ohio,
Maine, North Carolina, and Arkansas are using extensive field
biological data sets for defining what constitutes "expectable"
species richness, density, incidence1 of tumors, and/or percentage
of exotic species in environments which are believed to be the
most relatively "pristine" available. The variability within
this data set is also quantified. Through a public involvement
process and a review of toxicological data, "thresholds" for
agency action are established. These are intended to trigger
more finely-tuned (and costly) investigations of individual sites
to establish causal relations with specific contaminants, and
provide engineering recommendations for remedial action. In
establishing reference (expectable) values for a region, physical
or chemical measurements can be used as well. For example, to
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27
estimate the extent of acidification of surface waters in the
United States, EPA sampled hundreds of streams and lakes a
minimum of one time during a carefully selected season!s) and at
a point where a sample would be most likely to represent the
entire surrounding aquatic environment. While this did not
provide definitive answers regarding the causes or consequences
of acidification, it provided information useful for policy
decisions. It did so by quantifying the approximate portion of
sampled waters in various numerical range categories (e.g., of
alkalinity and other metrics), and described their spatial
variability. More geographically focused studies have followed.
The wetlands effort would not be as simple, due to the extreme
spatial variability within and among wetlands, as well as the
need to consider multiple interacting stressors (metals,
nutrients, hydroperiod alteration) rather than a single stressor
(acidic precipitation). Nonetheless, after initial testing of
protocols and indicators, a synoptic monitoring network for
wetlands could use biological and/or physicochemical measurements
to achieve a first approximation of the extent of wetland
ecological impairment, either nationwide or for specific wetland
types-regions.
5.2.2 Approach
This effort would be closely coordinated with and would build
upon the interrelated effort described above to examine water
quality criteria for wetlands (Component I). Specifically, the
field methods and remotely sensed metrics tested by Component I
would be put into practice in Component II.
Task l. Review of existing field protocols and data sources.
A first step would involve compiling existing measurements of
wetlands (e.g., invertebrate richness, sedimentation rates,
dissolved organic carbon) into type-region databases. Although
such numerical data would be based on diverse (and sometimes
undescribed) measurement protocols, it could be examined to
obtain a first estimate of the variability which may be expected,
and to place in a broader context any subsequent data collected
by EPA. It can also be used to identify sites where ongoing data
collection programs could be economically augmented by EPA.
Simultaneously, the limited literature concerning wetland
indicators would be synthesized and measurement techniques
compiled.
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28
Task 2. State-level prototype study.
Implementation of the monitoring network would begin by
establishing a state-level prototype. State-level programs would
be sought which could provide, through the amplification of
matching funds and use of locally experienced personnel, the
first broad, field-based testing of the wetland monitoring
methods. The state survey would provide numerical reference
points for several metrics in various wetland types. This field
survey approach would also help EPA further refine its monitoring
protocols, choice of indicators, and metrics.
Task 3. Full implementation.
At the completion of the first state prototype, the wetland
monitoring network would be expanded to encompass at least some
of the priority type-regions, and perhaps the entire nation. A
different priority wetland type-region would be surveyed per year
with a rotation for resurveys every 3 to 5 years. The projected
level of effort assumes monitoring about 150 wetlands per
priority wetland type-region per year at about $10,000 per
wetland, for a total of $1.5 million, or half of the projected
annual budget for the task. (This would be exclusive of costs for
data analysis and remote sensing data collection.) The selection
of the majority of these 150 sites should be stratified according
to systematic criteria such as the following.
One subset of about 10 of the projected 150 wetland sites would
be in previously well-studied wetlands, such as the National
Science Foundation's Long Term Ecological Research (LTER) sites
and/or others shown in Figure 3. In these, more detailed
(intensive) measurements would be performed. Another subset of
about 40 of the 150 wetlands would include wetlands known to
contain "special" taxa (ones especially sensitive to priority
contaminants, or which are regionally rare/declining).
The remaining sites (about 100) within each priority type-region
would be used to establish the array of "reference" or
"benchmark" wetlands. These sites would be randomly selected,
with consideration for representing the spectrums of both a
general exposure to degradation from water quality (near-pristine
to degraded sites) and the range of stressor-taxa combinations.
About one-third of such an array of status or reference wetlands
would hopefully represent nearly pristine conditions.
Thus, if monitoring involves a 3-year cycling of the recurrent
measurements, a total of about 450 wetlands nationwide (i.e., 3
region-types) would be examined recurrently; a five-year cycling
would involve 750 wetlands (i.e., 5 region-types). The monitoring
protocols would be continuously fine-tuned as monitoring
progresses, to improve the validity of the measurements. EPA
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Figure 3.
Existing Long-term Wetland Data Sets: Preliminary Inventory of Freshwater Sites
Sites were included if the same ecological measurements were made
(or are funded to be made) at least once every 3 years at exactly
the same location. The EPA Wetlands Research Program has ongoing
efforts to update this map (see p. 32) and appreciates hearing of
locations not shown.
1. Everglades (NPS)
2. Apalachicola (U.FL, USGS)
3. Okeefenokee (U.GA)
4. Buttermilk Sound (CE)
5. Savannah River (DOE)
6. North Inlet LTER (NSF, U.SC)
7. Coweeta LTER (NSF)
8. Dismal Swamp (USGS)
9. Windmill Point (CE)
10. Virginia Barrier Is. LTER
11. Nott Island (CE)
12. Niering wetland (Conn. Col.)
13. Hubbard Brook LTER (NSF)
14. Houghton Lake (U.Michigan)
15. Kellogg LTER (NSF)
16. Des Plaines mesocosm
17. Monroe Lake (U. Indiana)
18. Cache River (CE)
19,20,21. 111.- MiSS. R. LTER
22. N. Temperate Lakes LTER
23. Cedar Creek LTER
24. Cottonwood Lake (USGS)
25. Konza LTER (NSF)
26. Bolivar Peninsula (CE)
27. Jornada LTER (NSF)
28. Niwot Ridge LTER (NSF)*
29. Central Plains LTER (NSF)
30. Miller Sands (CE)
31. S. San Francisco Bay (CE)
32. King County (WDOE)
33. Nebraska Sandhills (USGS)
34. ELF Study (USDOD)
35. Rhode R. (Smithsonian)
36. Creeping Swamp (USGS)
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30
proposes that this monitoring effort be permanent, extending into
several future decades.
These sample sizes may not be sufficient to statistically predict
the condition of the regional wetland resources as a whole.
Nonetheless, the creation of this database would considerably
improve on our current knowledge of expectable "baseline" (or
reference) conditions in several regions, and its typical
variability.
5.2.3 Outputs
The results of the state-level prototype as well as the national
monitoring network would be presented as peer-reviewed EPA
reports. Results would be presented in the context of related
measurements that have been made by other researchers, agencies,
or divisions of EPA. The data would be analyzed to answer the
following questions:
o What are the regional background levels of the indicators,
and what percent of the region's wetlands exceed background?
o Do prevailing background levels fully support wetland
ecological integrity?
o What percent of the region's wetlands exceed criteria
recommended for protecting ecological integrity?
5.2.4 Potential Sources of Funding; Schedule
Potential Funding Sources
We estimate the proposed effort will require approximately
$3 million per year when fully operational in 1993, plus a total
of $1.1 million during the years 1989-1992.
(1) Assumes the 1989 effort is covered by existing funds, and
$20K per year is needed for updating and maintenance.
(2) One-year (1992) study only. Assumes partial matching funds
available from the state in which the prototype is conducted.
Task 1. Construct & Review Database
Task 2. State-level Prototype Study
Task 3. Full Implementation
1989 - 1994
Needed SK
80(1)
800(2)
3000(3)
(3) Per year, beginning in 1993.
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31
Schedule
The schedule is shown graphically in Figure 4, and is presented
narratively below.
Fiscal Year 1989
A regional compilation of wetland biomonitoring methods and value
ranges for community metrics will be prepared.
Fiscal Year 1990
Locations of existing wetland data would be entered onto a
Geographic Information System for analysis. As the database is
formulated, calculation of regional medians and variances could
begin.
Fiscal Year 1991
Analysis of existing biomonitoring data would be completed.
Planning would be completed for the 1992 state-level pilot study.
Fiscal Year 1992
The state-level pilot study could be conducted. Results would be
analyzed for applicability to any national monitoring network EPA
may develop.
Fiscal Year 1993
This would be the first full year of the priority-based national
monitoring network.
Fiscal Years 1994 to 1995 (3-year cycle) or to 1997 (5-yr cycle)
Implementation of the same program of Fiscal Year 1993.
Fiscal Year 1996 (3-yr cycle) or 1998 (5-yr cycle)
Resurveys of priority-based wetland type-regions would begin.
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32
Figure 4. Schedule and needed budget ($K) for COMPONENT II.
Ecological Status of the Wetland Resource
FY: £2
Task 1. Database 100
Construction
Task 2. State-level
Field Prototype
Monitoring of
Ecological Status
Task 3.
Full Implementation
21 12 51 M
100 100 20 20 20
800
3000 3000
TOTAL $K, COMPONENT (II):
FY89
100
FY90
100
FY91
100
FY92
820
FY93
3020
FY94
3020
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5.3 Waste Assimilation Limits of Wetlands
33
5.3.1 Rationale
Wetlands are commonly reputed to be transformers of undesirable
chemicals, and in the process of transforming these, the
chemicals may be removed or rendered harmless to life in
receiving waters. Thus, quantitative estimates of waste
assimilative limits of wetlands are of practical use to EPA for
several reasons. Constructed wetlands can be used in some
situations, with due regard for potential bioaccumulation and
dispersal of contaminants, as low-cost alternatives to wastewater
treatment plants. Natural wetlands can be used to intercept and
purify some types of nonpoint runoff, in situations where sources
are too numerous for engineering solutions and control of
pollutants at the source is impractical. On a landscape level,
this leads to a question: "What acreage of what type of wetlands
do we need to maintain or restore the water quality of a
particular receiving water?" On an individual site level, this
leads to a design question: "What engineering and biological
characteristics in constructed wetlands are optimal for
assimilating wastes?"
Hundreds of studies, many sponsored by EPA, have examined the
ability of wetlands to process various anthropogenic substances,
especially nutrients (Table 2, part 3). There are also manuals
which propose engineering specifications for optimal waste
processing by constructed wetlands. Yet, the existing ]cnowledge
has been inadequate to provide EPA with answers to some important
questions.
Of foremost concern is that we do not know, except for a few
individual wetlands, what are the "safe" loading rates for
wetlands. This gap has occurred because (a) wetlands lose their
assimilative capacity over time, yet few wetlands have been
studied for appropriately long periods, and (b) in the absence of
regional background data on unaltered wetlands, there has been no
consensus as to how to recognize "safe" loading, i.e., what is a
wetland with acceptable "integrity"?
There are other difficulties in generalizing from the host of
existing studies. Most study sites were chosen
opportunistically, without randomization or testing of their
regional representativeness, so that extrapolation is uncertain.
Many studies did not measure key hydrologic variables, thus
invalidating most of their conclusions. And many studies sought
only to prove that wetlands do transform substances, but never
(perhaps because of inadequate sample sizes) indicated which
characteristics of the wetland were most influential based on
statistical analyses or calibrated models. In a few cases where
predictive factors and their thresholds have been identified, the
complexity and time requirements of their measurement has slowed
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34
Table 2. Major literature reviews and syntheses.
I. EFFECTS OF WATER QUALITY ON WETLAND BIOTA
Benforado, J. 1984. The Ecological Impacts of Wastewater on
Wetlands: An Annotated Bibliography. EPA-905/3-84-002. U.S.
Environmental Protection Agency, Chicago, Illinois.
Biddinger, G.R. and S.P. Gloss. 1984. The importance of trophic
transfer in the bioaccumulation of chemical contaminants in
aquatic ecosystems. Residue Reviews 91:103-145.
Farnworth, E.G., M.C. Nichols, C.N. Vann, L.G. Wolfson, R.W.
Bosserman, P.R. Hendrix, F.B. Golley, and J.L. cooley. 1979.
Impacts of Sediment and Nutrients on Biota in Surface Waters of
the United States. U.S. EPA EPA-600/3-79-105. 331 pp.
Godfrey, P.J., E.R. Kaynor, S. Pelczarski, and J. Benforado
(Eds.). 1985. Ecological Considerations in Wetlands Treatment
of Municipal Wastewaters. Van Nostrand Reinhoid Co., New York.
Grue, C.E., L.R. DeWeese, P. Mineau, G.A. Swanson, J.R. Foster,
P.M. Arnold, J. N. Huckins, P.J. Sheehan, W.K. Marshall, and A.P.
Ludden. 1986. Potential impacts of agricultural chemicals on
waterfowl and other wildlife inhabiting prairie wetlands: An
evaluation of research needs and approaches. Trans. N. Am. Wildl.
Nat. Res. Conf. 51:357-383.
Johnson, W.W. and M.T. Finley. 1980. Handbook of Acute Toxicity
of Chemicals to Fish and Aquatic Invertebrates. Resource
Publication 137. U.S. Department of the Interior Fish and
Wildlife Service, Washington, DC. 98 pp.
Mayer, F.L. , Jr. and M.R. Ellersieck. 1986. Manual of Acute
Toxicity: Interpretation and Data Base for 410 Chemicals and 66
Species of Freshwater Animals. Resour. Pub. 160, US Fish Wildl.
Serv., Washington, DC. 579 pp.
Olsen, L.A. 1984. Effects of Contaminated Sediment on Fish and
Wildlife: Review and Annotated Bibliography. U.S. Fish wildl.
Serv. FWS/0BS-82/66.
Reynoldson, T.B. 1987. Interactions between sediment
contaminants and benthic organisms. Hydrobiologia 149:53-66.
Smith, J.A., P.J. Witkowski and T.V. Fusillo. 1988. Manmade
Organic Compounds in the Surface Waters of the United States--A
Review of Current Understanding. U.S. Geol. Surv. Circular
1007. 92 pp.
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35
Willford, W.A., M.J. Mac, and R.J. Hesselberg. 1987. Assessing
the bioaccumulation of contaminants from sediments by fish and
other aquatic organisms. Hydrobiologia 149:107-111.
GUIDANCE DOCUMENTS:
II. METHODS FOR SAMPLING WETLANDS
Borthwick, S.M. 1988. Impact of Agricultural Pesticides on
Aquatic Invertebrates Inhabiting Prairie Wetlands. M.S. Thesis,
Dept. Fishery and Wildlife Biology, Colorado St. Univ., Ft.
Collins, Colorado. 90 pp.
King County Department of Planning. 1987. work Plan for
Stormwater/wetlands Study, King County, Washington.
Krueger, H.O., J.P. Ward, and S.H. Anderson. 1988. A Resource
Manager's Guide for Using Aquatic Organisms to Assess Water
Quality for Evaluation of Contaminants. Biol. Rep. 88(20), U.S.
Fish Wildl. Serv. National Ecol. Research Center, Fort Collins,
Colorado. 45 pp.
Murkin, H.R. (Ed.). 1984. Marsh Ecology Research Program Long-
term Monitoring Procedures Manual. Delta Waterfowl Research
Station. Manitoba, Canada. 80 pp.
Plafkin, J.L. , M.T. Barbour, K.D. Porter, S.K. Gross, and R.M.
Hughes. 1988. Rapid Bioassessment Protocols for Use in Streams
and Rivers: Benthic Macroinvertebrates and Fish. USEPA
Monitoring and Data Support Division, Washington, D.C.
U.S. Army Corps of Engineers. 1987. work Plan for the Cache River
Study. Envir. Sci. Div., Waterways Exp. Stn., Vicksburg,
Mississippi.
U.S. Environmental Protection Agency. 1983. The Effects of
Wastewater Treatment Facilities on Wetlands in the Midwest.
Appendix A: Technical Support Document. USEPA Region 5, Chicago.
U S EPA-905/3-83-002.
U.S. Environmental Protection Agency. 1985. Freshwater Wetlands
for Wastewater Management Handbook. Chap. 9: Assessment
Techniques and Data Sources. USEPA Region 4, Atlanta, Georgia.
USEPA 904/9-85-135.
U.S. Environmental Protection Agency. 1986. Water Quality
Assessment: A Screening Procedure for Toxic and Conventional
Pollutants in Surface and Ground Water. USEPA Envir. Research
Lab., Athens, Georgia. EPA/600/6-85/002.
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36
U.S. Environmental Protection Agency. 1985. Standard Evaluation
Procedure, Ecological Risk Assessment. Hazard Evaluation Div.,
USEPA Office of Pesticide Programs, Washington, D.C. EP-540/9-85-
001.
MAJOR LITERATURE REVIEWS AND SYNTHESES:
III. EFFECTS OF WETLANDS ON WATER QUALITY
Adamus, P.R., L.T. Stockwell, E.J. Clairain, Jr., M.E.Morrow,
L.P. Rozas, and R.D. Smith. in review. Wetland Evaluation
Technique (WET), Volume I: Literature Review, Section 2.5:
Nutrient Removal/Transformation. Technical Report Y-88. U.S.
Army Corps of Engineers, Waterways Experiment Station, Vicksburg,
Mississippi.
Bernard, J.M., D. Solander and J. Kvet. 1988. Production and
nutrient dynamics in Carex wetlands. Aquat. Bot. 30:125- 147.
Carpenter, S.R. and D.M. Lodge. 1986. Effects of submersed
macrophytes on ecosystem processes. Aquat. Bot. 26:341-370.
Dickerman, J.A., A.J. Stewart, and J.C. Lance. 1985. The Impact
of Wetlands on the Movement of Water and Nonpoint Pollutants from
Agricultural Watersheds. USDA Agric. Res. Serv., Durant, OK.
Farnworth, E. G., M. C. Nichols, C. N. Vann, L. G. Wolfson, R. W.
Bosserman, P. R. Hendrix, F. B. Golley, and J. L. Cooley.
1979. Impacts of Sediment and Nutrients on Biota in Surface
Waters of the United States. U.S. EPA-600/3-79-105. 331
pp.
Godfrey, P.J., E.R. Kaynor, s. Pelczarski and J. Benforado
(Eds.). 1985. Ecological Considerations in Wetlands Treatment of
Municipal Wastewaters. Van Nostrand Reinhold Co., New York.
Howard-Williams, C. 1985. Cycling and retention of nitrogen and
phosphorus in wetlands: a theoretical and applied perspective.
Freshw. Biol. 15:391-431.
Limnol. Oceanogr. 33(4):l-687. (1988).
An entire issue containing several synthesis articles on aquatic
nutrient cycling, e.g.:
"Nitrogen fixation in freshwater, estuarine, and marine
ecosystems" (Howarth et al.)
"Forested wetlands in freshwater and salt-water
environments" (Lugo et al.)
"Denitri f icat ion in freshwater and coastal marine
ecosystems.: Ecological and geochemical significance"
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37
(Seitzinger)
"Physical energy inputs and the comparative ecology of lake
and marine ecosystems" (Nixon)
Nixon, S.W. and V. Lee. 1986. Wetlands and Water Quality: A
Regional Review of Recent Research in the United States on the
Role of Freshwater and Saltwater Wetlands as Sources, Sinks, and
Transformers of Nitrogen, Phosphorus, and Various Heavy Metals.
Draft, Corps of Engineers Waterways Experiment Station,
Vicksburg, Mississippi.
Reddy, K.R. and W.H. Smith (eds.). 1987. Aquatic Plants for
Water Treatment and Resource Recovery. Magnolia Publishing Inc.
USEPA. 1988. Design Manual: Constructed Wetlands and Aquatic
Plant Systems for Municipal Wastewater Treatment. USEPA Center
for Envir. Res. Informa., Cincinnati, Ohio. EPA/625/1-88/022.
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38
their routine use by EPA personnel, who often have but a few
hours or days to review an application for wetland alteration, or
to perhaps decide whether to assign a designated use of "water
quality purification" to a series of natural wetlands.
5.3.2 Approach
Task l. Use Mesocosms to Identify Determinants of Loading
Limits
EPA proposes to rely primarily on manipulative experiments in
freshwater wetland mesocosms to address the unanswered questions.
These mesocosm experiments should be integrated with an effort to
develop rapid quantitative models requiring only very minimal,
easily obtainable input data.
As noted above, a major hindrance has been recognition of what
constitutes a "safe" condition. However, the parallel effort in
Components I and II of this plan, by revealing appropriate
indicators and metrics, and attainable levels, could serve as a
foundation for setting this standard on a wetland type-region
basis.
Task 2. Conduct coarser-scale studies of selected determinants.
Data from empirical studies being conducted under a separate part
of EPA's Wetlands Research Program (Cumulative Effects) would
also be used to draw conclusions and improve the applicability of
the mesocosm results and models to coarser scales. Other
empirical studies, involving analysis of existing data sets
(e.g. , studies of wetlands located below waste discharges and
subject to long-term loading) would also be initiated at a lesser
level of funding than the mesocosm studies.
The problem of identifying factors responsible for the long-term
assimilative limits of wetlands, and recovery from the loss of
assimilative capacity, is not easily addressed by use of
mesocosms. Phosphorus is a key element of concern in the
unintended use of wetlands for nonpoint runoff treatment, and
Richardson (1985) found that sediment aluminum (in its amorphous,
extractable form) is a key predictor of long-term assimilative
limits for phosphorus. The empirical studies we propose could,
with some limited additional field sampling, seek to correlate
extractable aluminum to soil series and other landscape-level
characteristics. If this succeeds, and among-wetland variation
is greater than within-wetland variation, then regulatory
personnel may be able to use soil maps with supporting material
to provide a first approximation of wetlands likely to retain
phosphorus for long periods.
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39
Throughout the Component III effort, simple wetland models will
be used to help design the research. Both conceptual and
quantitative wetland models exist, but have high data input and
processing power demands. Simpler versions of these could be
tested and possibly calibrated in the mesocosm work. Much of the
manipulative experimentation would be designed to measure rate
coefficients and determine their spatial variability and
association with observable (particularly, remotely sensed)
wetland characteristics. The more easily measured rate
coefficients may be monitored in the Component II effort as well,
to develop these statistical associations. However, wetland
models will not be the primary output of the research, but rather
will help to guide it. In the near-term, these wetland models
could be refined for use at the scale of the individual wetland,
rather than for illustrating the cumulative interacting role of
many wetlands in a watershed.
Opportunities exist for collaboration. There are advantages and
disadvantages of using the same mesocosms in both the Component I
and Component III efforts. There are also opportunities for
influencing ongoing studies related to engineering design of
constructed wetlands, and empirical studies of stormwater basins
in Washington, Maryland, and other locations. All potential
collaborative opportunities must be viewed from the perspective
of providing EPA with information that can be used to develop a
categorization scheme or pollutant loading rate criteria for
wetlands of a given type generally, and which would be based on
observable characteristics which correlate with long-term
assimilative limits.
5.3.3 Outputs
Task 3. Report on "Safe" Loading Limits
"Safe" loading limits for six wetland type-regions might be
specified for phosphorus, nitrogen, two heavy metals, and a
limited number of priority organics. At greater funding levels,
"safe" levels for other wetland type-regions, or criteria in a
single type region for hydroperiod alteration and additional
contaminants, could be included. Models could be developed to
enable the user, given information on soil series or other
landscape features, to categorize wetlands according to their
probable long-term assimilative limits. Products would also
include peer-reviewed papers, EPA reports, and/or software.
5.3.4 Potential Sources of Funding; Schedule
Potential Funding Sources
We estimate the proposed effort will require approximately $2.63
million over the 6-year period. In contrast, only limited
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40
funds—approximately $200K per year—are available at present
from EPA's Wetlands Research Program. Additional funds might
become available through a "Constructed Wetlands Initiative"
being coordinated through the EPA-Cincinnati Lab. However, funds
in addition to those from these two sources are likely to be
required to successfully meet the program objectives.
(1) Assumes 6 mesocosm studies, each completed in 2 years and
each costing $280 ($140K per year). Objective is to identify
what determines wetland assimilation limits for phosphorus, two
heavy metals, and a limited number of priority organics. Assume
a need for proportionately greater funding if a wider variety of
wetland types and/or stressors are to be examined in the same
period of time.
(2) Assumes 5 regional analyses of existing data sets (beginning
in 1990), costing $150K each. These would involve correlational
examination of remotely-sensed landscape predictors of wetland
water quality function. Assume a need for proportionately
greater funding if more regions are examined per year.
(3) Involves literature review updates, development of simple
models, research synthesis, interim progress reports, and
technological information transfer.
The schedule is shown graphically in Figure 5, and is presented
narratively below.
Fiscal Year 1989
A 2-year study will be initiated in a single type-region
mesocosm, with paired control site. Preference may be given to
the use of natural wetlands, for the reasons described in
Component I. Simple wetland models will be used both for
experimental design, and to help predict the assimilative limits
of the studied wetlands.
Fiscal Year 1990
Manipulative experiments will be concluded on the first wetland
1989 - 1994
Needed SK
Task l. Mesocosm Identification of Determinants
Task 2. Empirical Studies of Determinants
Task 3. Report on "Safe" Loading Limits
1680 (l)
750 (2)
200 (3)
Schedule
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41
Figure 5. Schedule and needed budget ($K) for COMPONENT III.
Waste Assimilation Limits of Wetlands
Task l. Mesocosm Identification of Determinants of Limits
FY:
£1
1£
11
12
11
wetland
type/region
1*
140
140
wetland
type/region
2*
140
140
wetland
type/region
3*
140
140
wetland
type/region
4*
140
140
wetland
type/region
5*
140
140
wetland
type/region
6*
140
140
Task 2. Empirical Studies of Determinants of Limits
wetland
wetland
wetland
wetland
wetland
FY:
type/region 1*
type/region 2*
type/region 3*
type/region 4*
type/region 5*
£1
1£
150
li
150
22
150
11
14
150
150
Task 3. Reports on "Safe" Loading Limits
FY: £1 1Q II 12 13 14
25 25 25 25 100
TOTAL $K, COMPONENT (III):
FY89
140
FY90
455
FY91
595
FY92
735
FY93
455
FY94
250
Region numbers are hypothetical and do not necessarily
correspond with EPA administrative regions.
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42
type-region mesocosm, and a second mesocosm study would begin.
The first empirical study of determinants of wetland water
quality function would be implemented, and may emphasize
remotely-sensed landscape predictors of aluminum and
denitrification.
Fiscal Year 1991
A third and fourth mesocosm would be added, while the second year
of research continues on the second system. Empirical landscape
studies as developed in the previous year for studying aluminum
may be focused upon the investigation of denitrification in a new
region.
Fiscal Year 1992
Manipulative approaches and empirical landscape studies would
continue. Models to predict assimilative limits of wetlands
would approach completion, with reports issued on draft models.
Fiscal Year 1993
Manipulative approaches and empirical landscape studies would
continue. Models to predict assimilative limits of wetlands
would approach completion, with reports issued on draft models.
Fiscal Year 1994
Models to predict assimilative limits of wetlands would be
completed for the 5 wetland type-regions studied, with reports
and software issued on final models.
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43
6.0 LITERATURE CITED
Bayne, B.L. , R.F. Addison, J.M. Capuzzo, K.R. Clarke, J.S. Gray,
M.N. Moore, and R.M. Warwick. 1988. An overview of the GEEP
workshop. Mar. Ecol. Progr. Ser. 46:235-243.
Clarke, K.R. and R.H. Green. 1988. Statistical design and
analysis for a "biological effects" study. Mar. Ecol.
Progr. Ser. 46:213-226.
The Conservation Foundation. 1987. Protecting America's
Wetlands: An Action Agenda. The final report of the National
Wetlands Policy Forum. The Conservation Foundation, Washington,
D.C. 69 pp.
Giesy, J.P., Jr. (Ed.). 1980. Microcosms in Ecological
Research. U.S. Dept. of Energy, Washington, D.C.. NTIS # Conf-
781101.
Herron, R.C. 1985. Phosphorus Dynamics in Dingle Marsh, Idaho.
Ph.D. Dissertation, Utah State Univ., Logan, Utah. 153 pp.
Karr, J.R. and D.R. Dudley. 1981. Ecological perspective on
water quality goals. Envir. Manage. 5:55-68.
Nixon, S.W. and V. Lee. 1986. Wetlands and Water Quality: A
Regional Review of Recent Research in the United States on the
Role of Freshwater and Saltwater Wetlands as Sources, Sinks, and
Transformers of Nitrogen, Phosphorus, and Various Heavy Metals.
Draft, Corps of Engineers Waterways Experiment Station,
Vicksburg, Mississippi.
Okland, J. and K.A. Okland. 1979. Use of Fresh-water Littoral
Fauna for Environmental Monitoring: Aspects Related to Studies of
1000 Lakes in Norway. pp. 168-183 In: The Use of Ecological
Variables in Environmental Monitoring. The National Swedish
Environment Protection Board. Rep. PM 1151.
Ongley, E.D., D.A. Birkholz, J.H. Carey, and M.R. Samoiloff.
1988. Is water a relevant medium for toxic chemicals? An
alternative environmental sensing strategy. J. Environ. Qual.
17:391-401.
Peters, R.H. 1986. The role of prediction in limnology.
Limnol. Oceanogr. 31:1143-1159.
Schindler, D.W. 1987. Detecting ecosystem responses to
anthropogenic stress. Can. J. Fish. Aquat. Sci. 44
(Suppl.l):6-25.
Skalski, J.R. and D.H. McKenzie. 1982. A design for aquatic
monitoring programs. J. Envir. Manage. 14:237-251.
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44
USEPA. 1986. Quality Criteria for Water. Office of Water
Regulations and Standards, U.S. Envir. Protec. Agency,
Washington, D.C. EPA 440/5-86-001.
USEPA. 1987. Surface Water Monitoring: A Framework for Change.
Office of Water and Office of Policy, Planning, and Evaluation.
U.S. Environmental Protection Agency, Washington, D.C. 41 pp.
USEPA. 1988. Draft Framework for the Water Quality Standards
Program. Office of Water Regulations and standards. U.S.
Environmental Protection Agency, Washington, D.C. 41 pp.
U.S. Fish and Wildlife Service (USFWS). 1987. Letter from John
G. Rogers, Jr. , Chief of the Division of Environmental
Contaminants, to Dr. Frank Gostomski, USEPA Criteria and
Standards Division.
van der Valk, A.G., B.D.J. Batt, H.R. Murkin, P.J. Caldwell, and
J.R. Kadlec. 1988. The Marsh Ecology Research Program (MERP):
The organization and administration of a long-term mesocosm
study. Paper No. 45, MERP, Delta Waterfowl and Wetland Res.
Stn., Ducks Unlimited Canada.
Warwick, R. M. 1988. Effects on community structure of a
pollutant gradient—summary. Mar. Ecol. Progr. Ser. 46:207-211.
Zedler, J.B. and M.E. Kentula. 1986. Wetlands Research Plan.
EPA/600/3-86/009. U.S. Environmental Protection Agency,
Environmental Research Laboratory, Corvallis, Oregon. National
Technical Information Service Accession Number PB86 158 656/AS.
118 pp.
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APPENDIX A. SYNOPSIS OF THE SURVEY RESPONSES AND THE EASTON
WORKSHOP
As described in Section 2 of this Implementation Plan, scientific
input was sought by means of a questionnaire distributed by the
University of Florida, and by holding a workshop. Because the
workshop was structured to focus on the same questions as were
asked in the questionnaire, we have used these questions to
organize the input.
I. EFFECTS OF WATER QUALITY ON WETLANDS
QUESTION 1.1: WETLAND HEALTH
The questionnaire gave a working definition of wetlands health
as:
"The presence of physical, chemical, and geographic conditions
which will sustain the long-term aesthetic, assimilative, and
productive dynamics of the wetland resource and its regionally
indigenous organisms."
Both the questionnaire respondents and the workshop participants
urged replacement of the term "health" with "integrity".
Questionnaire respondents frequently recommended the inclusion of
a biological term, a hydrology term, deletion of the geographic
and aesthetic terms. At the workshop, participants discussed the
appropriate application of the following terms: aesthetic,
assimilative, geographic, biogeochemical, function, productive,
regional and indigenous organisms. They urged that a biological
term should be added as an explicit condition, although it is
also an objective. The importance of hydrology was stressed, but
was left as an assumed component of the physical term.
"Processes" were considered more inclusive than "function" or
"dynamics". Other deleted terms were considered too
anthropomorphic or restrictive.
QUESTION 1.2; "STRAWMAN" GUIDELINES FOR PROTECTING WETLAND
HEALTH
Most of these guidelines were developed and implemented by the
State of Florida in response to projects involving wastewater
additions to wooded wetlands.
Respondents were asked to indicate the adequacy of each of the
guidelines for protecting wetland health. Specifically,
respondents were asked to consider limitations associated with
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broadening the guidelines to include herbaceous (tidal,
nontidal), created, and hydrologically altered wetlands-
Evaluation criteria dealt with technical adequacy, relative
importance, clarity, and consistency among guidelines.
The questionnaire respondents were asked to register their
opinion of the technical adequacy of each guideline as "Quite
adequate", "Somewhat adequate", or "Inadequate". The subsequent
statistical analysis of these responses can indicate the strength
of agreement, as well as of preference. However, when the
responses show a strong central tendency (i.e., nearly all
respondents answering "somewhat adequate"), results are difficult
to interpret. In these
cases, whenever the skewing was towards "adequate", we have
characterized the group response as "slightly adequate", whereas
when it was skewed toward "inadequate", in the summary below we
have called the group's response "slightly inadequate".
The 15 guidelines and the group responses are as follows:
#1. Guideline:
SPECIAL AREAS: Wetlands designated as shellfish areas, habitats
of endangered/threatened species, designated ecologically
critical areas, and public water supply areas shall not be used
for wastewater treatment, and outfalls from any treatment wetland
must be > 24 hr. hydrologic travel time (average annual) upstream
from such areas".
#1 Response:
Guideline is slightly "adequate" for protecting the integrity of
natural and altered wetlands.
#2 Guideline:
EMERGENT WETLANDS: Primarily forested and shrub wetlands shall
be used; emergent wetlands (>30% herbaceous ground cover) shall
not be used unless dominated by cattail".
#2 Response:
Guideline is "inadequate" for protecting tidal-herbaceous
wetlands, and created and altered wetlands.
#3 Guidelines:
"LIMIT ROUGH FISH: In wetlands containing fish, a 10% decrease
in biomass of forage fish, or of sport and commercial fish; or a
25% increase in rough fish is not allowed unless the ratio of
sport and commercial fish to rough fish is maintained".
#3 Response:
"Adequate" for nontidal-herbaceous wetlands, "inadequate" for
created wetlands.
#4 Guideline:
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"LIMIT FISH BIOMASS IMPACT: Significant changes in biomass in
any fish species will be allowed only if the change can be
attributed primarily to changes in volume and depth of the
flooded area which are not related to the discharge (using
statistical covariance techniques)."
#4 Response:
"Inadequate" for created wetlands.
#5 Guideline:
"LIMIT TREE IMPACT: The importance value (a botanical metric) of
any of the dominant plant species in the canopy and subcanopy at
any monitoring station cannot be reduced by >50% (excluding
certain exotics)."
#5 Response:
"Slightly inadequate" for nontidal wetlands, "inadequate" for
created and altered wetlands.
#6 Guideline:
"LIMIT AVERAGE TREE IMPACT: The average importance value of any
of the canopy dominants shall not be reduced by >25%.
#6 Response:
"Adequate" for nontidal-wooded wetlands, slightly "adequate" for
tidal-herbaceous, "adequate" for created, and slightly
"inadequate" for altered wetlands.
#7 Guideline:
"MAINTAIN DIVERSITY INDEX: The Shannon-Weaver index (reflecting
diversity of benthic and epiphytic m acroinvertebrates, excluding
Chironomidae) shall not be reduced to < 50% of background
levels".
#7 Response:
"Inadequate" for created wetlands.
#8 Guideline:
"LOADING & DETENTION: Hydraulic loading rate shall be <5 cm/wk;
detention time shall be > 14 days unless demonstrated that
shorter times can meet above criteria".
#8 Response:
"Adequate" for wooded nontidal wetlands.
#9 Guideline:
"CONCENTRATIONS: Criteria for discharges of effluent into
natural wetlands shall be as follows (mean monthly values):
total nitrogen: 19 mg/1; ammonium: 2 mg/1; total phosphorus: 1
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mg/1; pH: within 1.0 of background".
#9 Response:
"Adequate" for natural nontidal and tidal wetlands.
#10 Guideline:
"SHEET FLOW: Channeling of flow shall be minimized; sheet flow
through the wetland shall be encouraged".
#10 Response:
"Inadequate" for wooded wetlands, "adequate" for tidal-herbaceous
wetlands, and strongly "adequate" for tidal-herbaceous, created
and altered wetlands.
#11 Guideline:
"PHYSICAL DIVERSITY: The diversity of physical habitats shall
not be measurably reduced from baseline condition".
#11 Response:
Responses showed no trends.
#12 Guideline:
"ENCOURAGE REGIONAL BIODIVERSITY: Where physically possible,
activities shall be located or designed so as to favor
hydroperiods and/or indigenous plants/vegetation types which are
relatively uncommon in the region (particularly those types which
have experienced greatest losses), and their sustaining
conditions."
#12 Response:
"Slightly inadequate" for natural nontidal wetlands.
#13 Guideline:
"MAINTAIN HYDROPERIOD: Baseline conditions with regard to
duration, frequency, timing, and extent of wetland surface water
shall be maintained."
#13 Response:
"Adequate" for natural wetlands and slightly "adequate" for
created wetlands.
#14 Guideline:
"MAINTAIN REDUCING CONCENTRATIONS: The identity and proportions
of reducing substances of the baseline (pre-efficient) wetland,
or that are typical (>80% similarity) of similar wetlands in the
region shall be maintained.
#14 Response:
"Inadequate" for natural nontidal wetlands and slightly
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"adequate" for tidal wetlands.
#15 Guideline:
"SEDIMENT ORGANIC ACCUMULATION: Sedimentation and organic
accumulation rates of the baseline wetlands, or that are typical
of similar wetlands in the region, shall be maintained.
#15 Response:
Slightly "adequate" for tidal wetlands.
General Evaluation of the Florida Criteria:
Despite their pleas for further research directed at refining the
criteria, questionnaire respondents believed that the criteria,
taken as a collective whole, are probably "adequate" for wooded
nontidal and created wetlands, and slightly "adequate" for
herbaceous and altered wetlands. The workshop participants, too,
were generally positive about these guidelines as a whole,
although most of the specific guidelines were considered either
"inadequate" for broad application to wetland types or
"inadequate" to approach. Participants generally felt the
guidelines were more adequate for created or altered wetlands
than for natural wetlands.
Participants strongly urged that the guidelines be modified
through research to reflect differences in wetland types-regions,
but fell short of suggesting specific changes that should be made
or hypotheses that could be tested.
Guidelines that were viewed as most critical for protecting
wetland integrity were those related to maintenance of
hydroperiod, loading and detention,
physical (habitat) diversity, sediment/organic accumulation, and
concentrations.
Participants urged that different guidelines be applied to non-
point and point sources, but there was little discussion of
specific adaptations that should be made. Some guidelines, such
as those dealing with vegetation and fish, were considered
appropriate in concept, but their numeric quantification was
questioned, considering the existing lack of supporting data.
The use of vegetation in criteria to assure wetland integrity was
questioned, considering the lack of data, difficult of
quantification, and the relatively slow and perhaps insensitive
response for some vegetation types.
The emphasis in several guidelines on maintaining diversity was
questioned, because "healthy" wetlands need not necessarily be
diverse. Sheet flow was also viewed as not being a prerequisite
to wetland integrity. Such guidelines may be especially
applicable to created and altered wetlands. Encouragement of
regional biodiversity was seen to be in conflict with many of the
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other guidelines. It might be applied more appropriately to
created or altered wetlands, or considered in permit conditions
on a case-by-case basis.
QUESTION 1.3: ADEQUACY OF EXISTING SURFACE WATER CRITERIA
An official list of EPA priority pollutants was presented under
the categories of nutrients, heavy metals, pesticides, organics,
synthetic organics and other water quality conditions.
Respondents were asked to indicate (a) the adequacy of existing
water quality criteria (for each substance) to protect wetland
health, (b) the likelihood that natural processes cause excedence
of the criterion, and (c) extent of personal experience with
specific criteria.
The questionnaire responses were too insufficient in number and
completion to be analyzed. Workshop participants generally felt
unqualified to assess specific numeric criteria. A matrix
showing the effect of some water quality conditions on a few
water contaminants drew some response.
QUESTION 1.4: ACTIVITIES THAT AFFECT WETLANDS
Participants were asked to indicate the extent and severity of
various activities and contaminant sources for their state.
Response categories were "very extensive or severe" , "moderately
extensively or severs", or "not extensive or severe."
Land clearing and tillage were generally viewed as the most
important threats to wetland water quality. Channelization and
dike-levee operation were also high in both scales.
Non-point sources were suggested as most extensive, but of
moderate severity. Agricultural runoff was the most extensive
followed by land drainage-irrigation and stormwater runoff, then
community landfills and forest management. All of these were
considered moderate in severity. Hazardous waste sites were not
considered extensive, but their severity was considered very
high.
Point sources were likewise ranked as not extensive, but severe
in impact. Domestic/industrial wastewater was the leading type
of activity impact (most extensive and severe) on wetland water
quality. Mineral/oil exploration and hazardous waste sites
followed in importance.
QUESTION 1.5: PRIORITIZING THE CONTAMINANTS
Respondents were asked to indicate the extent and severity of
major contaminant categories on three wetland types. Metals and
toxic elements were most consistently considered to have a very
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extensive (severe) impact on wetland water quality. Synthetic
organics were second in importance, with both having lesser
severity in tidal wetlands. Sedimentation was seen as severe in
non-tidal wetlands. Nutrients were recognized as extensive with
their severity of effect decreasing from non-tidal surface water
wetlands, to tidal wetlands, to non-tidal-no surface water
wetlands.
QUESTION 1.6 AND 1.7: WETLANDS MONITORING NETWORK
Respondents were asked to indicate taxa and process/conditions
(from lists provided) which might show promise as indicators of
wetland health, given various types of stressors. A second part
of the question requested evaluation of thirteen community
metrics commonly used to evaluate structural data.
The questionnaire responses were too insufficient in number and
completion for analysis. At the workshop, participants were
asked to assume a budget of $2000 per wetland per year. There
was strong sentiment that this would be insufficient for
establishing a credible regional wetland monitoring network.
However, if such a network were implemented, participants felt
that effort should focus on analysis of sediments (deposition
rates, organic content, contaminant levels). Macroinvertebrates
(especially sessile detritivores and filter feeders) were listed
as potentially useful indicators of metals and toxics (and
mentioned for sediment). Community composition descriptions were
mentioned as an indicator of change for all pollution types.
Among process measurements, productivity was considered as a
potentially suitable indicator of artificial nutrient enrichment.
The temporal and episodic variation of water monitoring versus
biological monitoring was a major discussion topic among workshop
participants.
QUESTION 1.8: REMOTE SENSING
Questionnaire respondents suggested that the most easily measured
feature using remote sensing would be the ratio of vegetated to
open water areas.
However, the feature most relevant to determining wetland
integrity would be vegetation cover type.
From a list of biological features that might be remotely sensed,
workshop participants believed that biomass was the most relevant
remotely-sensed feature, followed by cover type. Leaf area is a
difficult parameter for remote sensing (if the intent is leaf
area index and not just percent ground cover) and generally was
not recommended. Greenness, although a historical remote sensing
term, has a confusing interpretation in an ecological framework
and is likewise not preferred.
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The percent area of shallows containing emergents was judged most
relevant to estimating wetland integrity, with moderate ease of
measurement. The ratios vegetation/open water, wetland/deep
water and edge irregularity index, although easy to measure, were
not seen as very relevant, necessarily, to wetland integrity. A
measure of the flushing or exchange surface (open water to
wetland flux) were added suggestions.
From a list of physical properties that might be remotely sensed,
participants believed that hydroperiod was relatively easy to
determine and had high relevance. Turbidity was rated slightly
lower than hydroperiod. Flow braiding was seen to have low
relevance to integrity, but is easy to measure. Organics and
geomorphic conditions were additionally suggested as properties
that might be both remotely sensed and sensitive to anthropogenic
stress.
QUESTION 1.9: TYPE OF SUPPORTING DATA COLLECTION
Respondents were asked what relative emphasis they would assign
to regional surveys vs. laboratory bioassays, given the goals of
cost-effectively developing and enforcing water quality criteria
for wetlands. No clear preference was shown among questionnaire
respondents, but workshop participants preferred regional
surveys. Also, no preference was apparent for using stratified
random sampling (as opposed to intentionally selecting the "most
pristine" sites), nor was any preference shown for using tissue
analysis (vs. field biosurveys or chemical surveys). If
bioassays are used, but the respondents and the workshop
participants favor multiple species, in situ bioassays over the
traditional single-species laboratory approaches.
II. EFFECTS OF WETLANDS ON WATER QUALITY
QUESTION 1. RESEARCH APPROACHES: INTERIM AND LONG-TERM
Respondents and workshop participants were asked to indicate the
probability of success, and cost effectiveness, of Literature
Reviews, Workshops, Empirical Landscape Analyses, and Mechanistic
Model Simulations for addressing short-term EPA needs.
As expected, the need for integration of all these components was
emphasized. Literature reviews and workshops were viewed as
being lower-cost options, and use of existing models in
simulations was viewed as being less likely to succeed than
developing new models, or using the other approaches.
QUESTION II.2: KEY FACTORS
Respondents and participants were asked to indicate the
usefulness of several factors, if these were used in mesocosm
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manipulations and ultimately are used for classifying wetlands
according to their assimilative capacity.
For tidal wetlands, the vegetation density, duration of tidal
inundation, and loading rate were viewed as most useful
descriptors of assimilative capacity.
For non-tidal surface-water wetlands (e.g., deep marshes), the
hydroperiod, detention time, sediment organic content, rjedojq-\
potential, position in watershed, and loading rate were viewed as
most useful.
For non-tidal no -surface-water wetlands (e.g., bogs and wet
meadows), the duration of inundation and position in watershed
were considered most useful.
QUESTIONS II.3 AND II.4: CONFLICTING HYPOTHESES, THRESHOLDS
These questions dealt with commonly-stated hypotheses about
wetlands which seem to be in conflict, and with advisable widths
for buffer zones. Responses were insufficient to allow analysis,
and at the workshop, time was insufficient to adequately address
these.
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