Final Report: Community Values and the Long-term Ecological Integrity of Rapidly Urbanizing Watersheds
EPA Grant Number: R825758Title: Community Values and the Long-term Ecological Integrity of Rapidly Urbanizing Watersheds
Investigators: Beck, Michael B. , Norton, Bryan G. , Patten, Bernard C. , Rasmussen, Todd C. , Steinemann, Anne C.
Institution: University of Georgia , Georgia Institute of Technology
EPA Project Officer: Perovich, Gina
Project Period: June 1, 1998 through May 31, 2001 (Extended to February 28, 2004)
Project Amount: $849,999
RFA: Water and Watersheds (1997)
Research Category: Water and Watersheds
Description:
Objective:This research project sought to integrate ecological, hydrological, and the social/policy sciences in a study of a rapidly urbanizing watershed (Lake Lanier, Georgia), where preservation of long-term ecological integrity is perceived as being at stake. More specifically, our goals were to: (1) develop a concept of environmental decisionmaking in which science-based models are responsive to identified community values, as they evolve in both the short and long term; (2) develop and apply a procedure for identifying those scientific unknowns that are crucial to the "reachability" of the community's desired/feared environmental futures; and (3) improve understanding of basic aspects of lake ecosystem behavior, with special reference to the roles of the microbial foodweb, sediment-nutrient interactions, and geochemistry.
Research towards the first of these goals was expected to culminate in a more general framework. We refer to this framework as "adaptive community learning," that will be facilitated over time with continual mutual feedback between the formation of stakeholder concerns, and exploration of their plausibility in terms of the science-based model.
The project was designed and implemented as a conventional applied systems analysis in which research in a specific problem setting was undertaken (i.e., the case study of Lake Lanier, with the objective of extracting from this practical experience a procedure and body of methods capable of more general applicability). In other important ways, however, the scheduling of project activities departed significantly from the norm, because of the way in which the procedure of adaptive community learning became defined. In particular, field and laboratory work directed at the more basic scientific questions should be implemented as one of the last steps in this procedure (as apparent from our findings below).
Our case-study watershed, the Upper Chattahoochee River upstream (northwards) of Buford Dam on Lake Lanier, is located between the two development corridors of I-75 and I-85 heading north from Atlanta, which is located just to the south of Lanier. A social history of the lake and its watershed indicates a general pattern of fragmentation-with many groups of stakeholders (individual, professional, and institutional)-with a high frequency of lawsuits and legal challenges among them, especially in the more recent past and continuing up to the present. The companion natural history of Lanier shows a decline over the years in its overall health as gauged by the headline figure of its annual mean hypolimnetic dissolved oxygen (DO) deficit. In addition, the lake has always exhibited a high trapping efficiency for the nutrient, phosphorus (P); only a small portion of the P entering the lake from its watershed is observed to be passed downstream. In the future, a situation where further urbanization of Lanier's watershed is highly likely, careful, collective control of the multiple stressors of the loadings of nutrients (primarily P), organic carbon (C), sediments, and iron (Fe), seems essential.
Summary/Accomplishments (Outputs/Outcomes):The Water and Watersheds Research Program, especially
in its later years (the funding cycles in 1997 and 1998), has had the core missions
of: (1) promoting fully integrated, interdisciplinary research; and (2) thereby
training future generations of graduate students capable of working with ease
in such interdisciplinary settings. Broadly speaking, and despite the additional
management overhead of a project such as ours, the payoff on both of these accounts
has been an unqualified success. We found that the greatest challenge of the
project, but also its most rewarding aspect, was to bridge the conventional
divide between the engineering and social sciences. The first 24 months of the
project were dedicated to achieving this integration. However, when attained,
all participants appreciated the significance of the cation exchange capacity
of Fe-rich Piedmont soils as much as the significance of the egalitarian social
solidarity of cultural theory (as a perspective on the human-environment relationship).
In response to our first objective, the prototypical shell of our general procedure
of adaptive community learning involves an iterative, cyclical process entailing
the following elements:
(1) Identifying stakeholder concerns for the future.
(2) Developing mathematical models, as maps of the current science base (with all its uncertainties, knowns, partially knowns, and unknowns), to assist in exploring those concerns.
(3) Formal, computational assessment of the stakeholder-generated, potential futures.
(4) Communicating to stakeholders the plausibility or otherwise of their feared/hoped-for futures.
(5) Identifying the key scientific unknowns (critical model parameters) on which realization of the potential future outcomes may crucially turn.
(6) Designing further experimental/field tests to reduce the uncertainty of the key unknowns, and in turn to reduce the uncertainty of any forecast future outcomes.
Departure from the norm of a more conventionally scheduled research project is now apparent, in that implementing field and laboratory work is the last item in the above schedule, as opposed to being one of the initial steps.
To place the procedure of adaptive community learning in context, the following may be of help. We know what adaptive management is. In essence, policy therein fulfills two functions: (1) to probe the behavior of the environmental system in a manner designed to reduce uncertainty about that behavior (i.e., to enhance learning about the nature of the physical system); and (2) to bring about some form of desired behavior in that system. Adaptive community learning ought to subsume the principles of adaptive management (so defined) and include actions or a process of decision making, whereby the community of stakeholders experiences learning about itself, its relationship with the valued piece of the environment (i.e., the community-environment relationship), and the functioning of the physical environment. Whereas professional staff within a management agency put their learning into action, thus influencing the behavior of the environmental system under the maxim of adaptive management, it will be readily apparent how individuals within a learning stakeholder community not professionally or institutionally charged with the responsibility of management could change the influences of their everyday actions on the future course of that system.
Part of our project's first goal was to be responsive to the concerns of stakeholders in our research. In particular, we focused on the way we developed the applied models for generating environmental foresight and for exploring stakeholder futures. The procedure of adaptive community learning departs from this task of identifying stakeholder concerns for the future as the first of its steps, thereby giving it prime importance. Our findings in this respect are as follows:
Two procedures were employed in order inter alia to elicit stakeholder concerns for the future, specifically in a manner compatible with a computational model of lake behavior: (1) an extensive questionnaire; and (2) a Foresight for Lanier Workshop. The former, while it yielded other insights-for example, that concerns were heightened amongst the community in the longer-term (20-30 years) relative to the shorter-term (3-5 years)-failed to deliver the required (quantitative) target future behavior definitions. However, it was readily apparent that the key concerns of stakeholders were "bacteria" (pathogens) in the lake water and that the water would be "unsafe for swimming," both notably facets of the issue of public, as opposed to ecological, health.
The Foresight Workshop was more successful in this respect. Stakeholders defined their own indicators of water quality and developed optimistic and pessimistic behavior definitions for the longer-term future, which were eventually transcribed successfully into the numerical bounds required for the analysis of reachable futures.
Step (4) of the foregoing outline of adaptive community learning calls for the outcomes of the computational analysis of uncertainty/reachability (i.e., the plausibility or otherwise of the feared/hoped-for futures), to be communicated back to stakeholders. The delay arising from the less than completely successful design of the survey instrument, with the unplanned recourse to the Foresight Workshop, left us with insufficient time to fully implement Step (4) through a second workshop.
Our second project objective called for the demonstration of a new computational approach to generating environmental foresight, in effect, implementation of Steps (2) and (3) of the procedure of adaptive community learning, with outcomes sought with respect to Steps (4) and (5) thereof. Under this objective, we have found the following:
The project has taken the widely used method of Regionalized Sensitivity Analysis (RSA) and successfully remedied two of its prior limitations in: (1) adjoining a Tree-Structured Density Estimation (TSDE) procedure to the RSA, to assess multivariate features of the sensitivity analysis (RSA results are univariate in character); and (2) circumventing small-sample size problems, which often arise with the RSA, using a Uniform Covering with Probabilistic Rejection (UCPR) algorithm.
To the best of our knowledge, the RSA has previously been used to identify key model uncertainties with respect to the matching of definitions of past behavior. Our project-using the composite RSA-TSDE-UCPR procedure has successfully addressed the same task in the context of (stakeholder-derived) definitions of future behavior, under gross uncertainty.
Outcomes of interest to stakeholders are results similar to there being a 2-3 times greater likelihood of their optimistic future coming to pass relative to the occurrence of their pessimistic future. These results have yet to be communicated to stakeholders.
Outcomes of interest to the scientific project team from the analysis of reachability take the following illustrative form-as just one of several such pointers towards promising and needed lines of more basic enquiry and experiment: what might matter most to the reachability of stakeholders' desired future is a better understanding of how phosphorus is released from sediments and propagated along a microbially-based foodchain (up to larval fish) in the lower hypolimnetic waters of the lake.
To place the success of our procedure in context, we observe that the RSA had previously been applied to models containing of the order of 10-30 parameters; in the present project, this figure has been increased to an excess of 100 parameters; and in a successor project with the U.S. Environmental Protection Agency (EPA), our procedure applied to a very high-order model (VHOM) containing some 1,000 parameters (for contaminant tracking in a multimedia context).
The third goal of the project called for the making of progress on the science base of lake biogeochemistry, specifically and significantly, in directions tailored to the concerns of stakeholders (i.e., through implementing Step (6) in our procedure of adaptive community learning). Planning a research project with this is mind-before funding has been acquired-is challenging because the field and laboratory work that may eventually need undertaking will not be apparent until possibly the end of the project, as happened in part herein. While some of the work towards attaining our third objective is still ongoing, these are our findings to date:
A new aquatic food-web model was developed for analysis of the reachability of the longer-term target futures as envisioned by stakeholders. A salient feature of the model is its incorporation of a "microbial loop," in which P can be propagated through heterotrophic bacteria and then microzooplankton up to higher trophic levels (in contrast to the phytoplankton, macrozooplankton pathway).
A new model for the behavior of biogeochemical interactions in the vertical profile of a lake system was also developed, consolidating a description of the dynamics of Fe and carbonate (pH) chemistry with the more conventional C, P, and N cycles usually present in lake water quality models. The purpose of this second model, in concert with the results of significant progress in modeling the transport of sediments and particulate-associated P into the lake from its tributaries, is to explore shorter-term extrapolations of the impacts of watershed management strategies on headline features of lake water quality, such as pH and the hypolimnetic DO deficit.
Having evaluated earlier the feasibility of continuous monitoring of whole-pond liming/fertilization manipulations over several months (in 1998), and being aware of the high trapping efficiency of Lanier with respect to P in 2000, we implemented a set of manipulations designed to test the availability of soluble orthophosphate in the presence/absence of suspended, Fe-rich Piedmont soil particles. From these manipulations, we have been able to conclude that Piedmont soils have a very substantial capacity to sequester P species in aquatic environments, implying that any controls over suspended sediment loadings and nutrient loadings should be introduced from a multiple-, as opposed to single-stressor perspective.
In concert with the 2000 exercise in continuous monitoring of the pond, and in response to the priority concern of stakeholders for "bacteria," Idexx Colilert equipment and sampling for coliform bacteria across the coupled pond-watershed system was conducted over several months during summer and fall. The fate and transport of indicator organisms through this experimental system is closely tied to hydrological events, as expected. The expected importance of the small pond in curtailing the further propagation of organisms out of the watershed has also now been demonstrated. However, if temperatures are sufficiently high, some regrowth of the bacterial population in the pond is possible, and there is an evident-although yet to be explained-temporal correlation between variations in coliform counts and (continuous) chlorophyll-a observations.
Previous long-term monitoring of DO conditions in the vertical profile of Lanier, which had ceased in 1997, were resumed in 2001, with continuous monitoring equipment not previously deployed in this manner. Preliminary results provide empirical evidence of the occurrence of persistent reducing conditions towards the bed of the lake, but-unusually-no discernible release of soluble P from the sediments.
Two of these findings, have provoked the specification of a new set of hypotheses about the nature of the P cycle in lake systems, and its interaction with the Fe and organic C cycles. These hypotheses are now being tested in a suite of ongoing laboratory studies.
It is fair to conclude that the quality and resources of Lake Lanier are one of the most hotly debated environmental issues in Georgia. It may be considered a success for the project team (perhaps only for those from a background of engineering and natural sciences) to have come to appreciate the fact that we are inextricably, and literally, a part of the problem-no matter how discomforting this conclusion may be. This realization gave us pause for thought. That can be turned to fruitful advantage, especially in the first of the following set of recommendations:
Given that we have just completed an experiment, in the spirit of what is now termed by some, "mission-oriented science," we believe we have an obligation to report on the outcomes of this experiment. In fact, we have begun preparing a paper recounting the results our reflexive examination of the conduct of the entire project, in this light.
The pause-for-thought during the period of the project has left us with an agenda of unfinished business. The very first item of which should be to report back to stakeholders on our analyses of their hopes and fears for the future, thereby completing at least one turn of the cycle of adaptive community learning.
It also is clear that our laboratory and field work on the biogeochemistry of Piedmont impoundments must be completed.
There is a prima facie case for the nascent concept, or procedure, of adaptive community learning to be applied and further developed in other situations; for example, in exploring strategies for change in the water infrastructures of cities of the future that might be deemed more sustainable than those of today, or in integrated assessments of issues of global environmental change.
There is likewise a prima facie case for adapting the participatory inverse approach of adaptive community learning, and its embedded computational means of generating environmental foresight, towards the notion of participatory technological envisioning, which would seem to fit comfortably within the span of the recent call for a Sustainability Science to be developed in the coming decades.
Journal Articles on this Report: 16 Displayed | Download in RIS Format
Other project views: | All 92 publications | 21 publications in selected types | All 16 journal articles |
Type | Citation | ||
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Beck MB, Fath BD, Parker AK, Osidele OO, Cowie GM, Rasmussen TC, Patten BC, Norton BG, Steinemann A, Borrett SR. Developing a concept of adaptive community learning: case study of a rapidly urbanizing watershed. Integrated Assessment 2002;3(4):299-307. |
R825758 (Final) |
not available |
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Beck,M.B.. Vulnerability of water quality in intensively developing urban watersheds. Editorial. Environmental Modelling & Software. 2005; 4 (20) : 379- 380 |
R825758 (Final) |
not available |
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Borrett SR, Patten BC. Structure of pathways in ecological networks: relationships between length and number. Ecological Modeling 2003;170:173-184. |
R825758 (Final) |
not available |
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Cowie GM, Borrett SR. Institutional perspectives on participation and information. Environmental Modelling & Software 2005;20:469-483. |
R825758 (Final) |
not available |
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Fath BD, Beck MB. Short-and long-term environmental perceptions: a case study of Lake Lanier. Environmental Modelling and Software. 2005, 20 (4):485-498. |
R825758 (Final) |
not available |
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Norton BG. Pragmatism, adaptive management, and sustainability. Environmental Values 1999;8(4):451-466. |
R825758 (Final) |
not available |
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Norton BG, Steinemann A. Environmental values and adaptive management. Journal of Policy Analysis and Management 2001, Volume: 10, Number: 4 (NOV), Page: 473-506. |
R825758 (1998) R825758 (1999) R825758 (Final) |
not available |
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Osidele OO, Beck MB. Identification of model structure for aquatic ecosystems using regionalized sensitivity analysis. Water Science and Technology 2001;43(7):271-278. |
R825758 (Final) |
not available |
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Osidele OO, Beck MB. Food web modelling for investigating ecosystem behaviour in large reservoirs of the south-eastern United States: lessons from Lake Lanier, Georgia. Ecological Modelling 2004;173(2-3):129-158 |
R825758 (Final) |
not available |
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Steinemann A. Rethinking human health impact assessment. Environmental Impact Assessment Review 2000;20(6):627-645. |
R825758 (2000) R825758 (Final) |
not available |
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Steinemann A. Improving alternatives for environmental impact assessment. Environmental Impact Assessment Review 2001;21(1):3-21. |
R825758 (Final) |
not available |
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Steinemann A. Implementing sustainable development through problem-based learning: pedagogy and practice. Journal of Professional Issues in Education Engineering and Practice 2003;129(4):216-224. |
R825758 (Final) |
not available |
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Zeng W, Beck MB. Development and evaluation of a mathematical model for the study of sediment-related water quality issues. Water Science and Technology 2001;43(7):47-54. |
R825758 (2000) R825758 (Final) |
not available |
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Zeng W, Beck MB. STAND, a dynamic model for sediment transport and water quality. Journal of Hydrology 2003;277(1-2):125-133. |
R825758 (Final) |
not available |
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Zeng X-Q, Rasmussen TC. Characterization of Lake Lanier water quality using principal components and cluster analysis. Journal of Environmental Quality 2005;34(6):1980-1991. |
R825758 (2000) R825758 (Final) |
not available |
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Zeng XQ, Rasmussen TC. Multivariate statistical characterization of water quality in Lake Lanier, Georgia, USA. Journal Of Environmental Quality. 2005;34(6):1980-1991. |
R825758 (Final) |
not available |
water, watersheds, sediments, adsorption, ecological effects, human health, pathogens, aquatic ecosystems, community-based public policy, social survey, engineering, social science, ecology, hydrology, limnology, geology, mathematics, modeling, monitoring, southeast region, Georgia, GA, agriculture. , Economic, Social, & Behavioral Science Research Program, Water, Scientific Discipline, RFA, Water & Watershed, decision-making, Economics & Decision Making, Biochemistry, Hydrology, Watersheds, Ecology and Ecosystems, Geochemistry, stakeholder feedback, water quality, ecosystem valuation, public policy, community-based research, ecology assessment models, ecological indicators, aquatic ecosystems, availability of water resources, lake ecosysyems, biogeochemical study, coefficient variations, Monte Carlo simulations, long term ecological integrity, water resources, microbial food web, urban watershed rehabilitation method
Relevant Websites:
http://hilbert.forestry.uga.edu/beck/
http://www.uga.edu/water/
Progress and Final Reports:
1998 Progress Report
1999 Progress Report
2000 Progress Report
Original Abstract