Ecosystem+theory+in+restoration


 * Ecosystem Theory in Restoration **

By George Garcia

=** Introduction **=

Water management historically has primarily been for the benefit of society and not the environment. It was considered an engineering feat to move water away from watersheds, utilize the power of water to generate electricity, to slow the movement of water to prolong the availability; the list goes on and on how engineers have harnessed the power of water to provide different uses. Although, with these advances new problems arise, not to mention changes in the environment; have we made a mistake, how could we not have seen this, why isn’t the system working the way we planned, and should we care about the environment, etc.? Every year we learn that our changes may not have been best for the system; we attempt to reconnect the ecosystem to the rivers and provide the service we expect for society. Ecosystem restoration is becoming a bigger and bigger topic as we realize our mistakes. New questions arise from this realization: where do we start?; where do we end?; how do we do it?; how does the restoration benefit society?; how much will it cost?; etc., the foundation to the answers to these question lay in the theories of restoration.

Restoration theory is an evolving study but has a central point of connection across all systems, “return the system to a condition prior to the disturbance” (Berger 1990 and NRC 1992). This central point is a difficult challenge to address. There are so many changes within watersheds to provide functions for society that we realize these changes may not be for the best of the system. The current realization (although not for everyone) is that the ecosystem should be maintained along side the societal functions.

Before, the system can be maintained it is felt that the system needs to be restored and thus restoration projects are enacted for many different reasons and the theory that is the foundation is not easily understood. Three strong and broad theories that have been applied to restoration projects are; the River Continuum Theory, eco-engineering theory and resilience theory and can serve as foundations for restoration projects. All three theories provide a means to evaluate the benefit of restoration projects and all three suggest evaluations both in the short term and long term are necessary.

There is not a simple answer to “what is the best restoration theory”, each system is different, each objective is different and changes to the system are different. Restoring a river to a “historical” natural system may not be possible. The simple fact that systems were manipulated to provide a service to society puts the most difficult constraint on any project. These three theories provide baseline knowledge for project managers and policy makers to utilize.

=** Restoration Theories **=

The understanding of a river system's continuous gradient of physical and biological factors is the underlying bases of the River Continuum Concept (RCC). River systems have a balance of energy, organic matter, storage, and food webs that make up their steady state. The geomorphology is the physical adaptation of the system to disturbances and the ecosystem represents the biological adaptations of the system. The RCC provides a foundation for explaining theorized and observable biological features of a system with the geomorphic environment (Vannote 1980).
 * The River Continuum Concept**

The RCC provides an extreme theoretical view of a river system. The RCC is a framework for the different functions of a river system: food chains, energy balance, structure and ecosystems and the hypothesis that there is a connection that returns the system to its steady state after disturbances. The system itself will have mini-systems through out its reaches and this helps the system to recover from natural changes in the system. Take for example a flood event: the system must balance the energy after the event; first the system will dissipate the energy of the flow by possibly over banking (flood plain and environmental flows), the flood will increase the detritus and the system will have to increase the detritus collectors and consumers, this balancing act will propagate up the food chain all along the system until the system is brought back to steady state. An important aspect the RCC is the predictability the fluctuating system and the optimum conditions for supporting large numbers of species and the response of the ecosystem to stabilize and maintain the uniformity of energy flow (Vannote 1980). Although based on real observations, the RCC is difficult to incorporate into restoration projects due to the fact that restoration projects are not able to be applied to the whole system and not to mention river systems are managed to serve specific functions.

When a system is managed to serve a social function (e.g. flood control, water diversion, etc.) it is difficult to predict the continuum much less apply the theory to restoration or management of the system. Vannote (1980) specifically states that the RCC is to be applied to a natural undisturbed system. This is in part due, every manipulation creates a disturbance that will constantly alter the cycle of the food web, ecosystem services, geomorphology and natural regime of the system. It could be assumed that the system will adjust and establish a new continuum. As suggested by resilience research the social-ecological interaction will establish a new system and return to this state after natural perturbations. The connection of floodplains, repairing of riparian zones, addressing ESA, etc. all work to bring a system back to its natural order and thus repairing its continuum. The RCC is an excellent foundation for the application of restoration projects and eco-engineering.

Eco-engineering is defined as the design of sustainable ecosystems that integrate human society with its natural environment for the benefit of both (Mitsch and Jorgensen 2003). This definition addresses directly the ideology of both engineers and environmentalist. Past engineering projects are examples of the lack of understanding of the importance of a systems full functionality and only being concerned about the end product and function provided to humanity; ignoring the system and the potential for future disturbances. The goals of eco-engineering are: 1) the restoration of ecosystems that have been substantially disturbed by human activities and 2) development of new sustainable ecosystems that have both human and ecological value (Mitsch and Jorgensen 2003). Many restoration projects are only able to work towards a few ends due to many constraints and limitations. As the scientists, engineers, managers and policy makers start to come together to understand that the sustainability of an ecosystem is paramount to the function of the system, a better understanding of the application of restoration projects and provide for better management of the systems.
 * Eco-Engineering**

Ecological engineering has determined some basic concepts to differentiate it from conventional approaches (Mitsch and Jorgensen 1989):

1) It is based on the self-designing capacity of ecosystems; 2) It can be the acid test of ecological theories; 3) It relies on system approaches; 4) It conserves non-renewable energy sources; and 5) It supports biological conservation.

Each concept is further explained in detail in their book. Very briefly, the self-designing of a system can be related directly to the RCC. This suggests that natural changes/perturbations in the system are adjusted to relatively quickly, where as human manipulations may not be able to be adjusted at all. When considering eco-engineering, it is the system's ability to adjust that can be utilized to implement restoration and/or system function projects (Mitsch and Jorgensen 1989). The idea of eco-engineering or ecosystem restoration being an acid test for theories and applications is best defined by the statement “the most valuable and powerful ways of studying something is to attempt to reassemble it, to repair it, and to adjust it so that it works properly” (Jordan //et al.//, 1987). The idea of restoration as an acid test for theories help develop the theories; as restoration projects do not lead to expected outcomes. Monitoring of restoration is a common suggested evaluation of all projects (Choi 2004, Palmer 1997 and Walker 2004,). This leads directly into the next concept of system approaches. Due to constraints on river systems, it is difficult to apply system approaches, but as information and research becomes available, restoration solutions can become more holistic. Setting restoration goals, monitoring and the acceptance of possible unexpected outcomes provide for a systematic approach (Choi 2004). The concept of non-renewable energy conservation encompasses the importance of the natural order of ecosystems. This concept can be related to the RCC and the energy flow of river systems and its ability to return to steady state after perturbations, although, many restoration projects will need additional management due to “function” manipulations. Ecosystems are solar energy driven and restoration projects need to account for the transition between non-renewable and renewable energy balance (Mitsch and Jorgensen 2002). Biological conservation has become a reactive response to misguided and mis-understood management (Mitsch and Jorgensen 1989). Ecosystem services are being recognized to play a vital role in the function that ecosystems are being engineered to provide. As systems are managed to provide sociological functions, conservation is imperative or the system will fail. Conservation of the over arching system will help the system to be resilient and rehabilitate itself. Eco-engineering involves identifying the biological systems that serve human needs as well as the function of the rivers adaptability. (Mitsch and Jorgensen 2002).

Resilience can be defined as the capacity of a system to absorb disturbance and reorganize while undergoing change so as to retain essentially the same function, structure, identity and feedbacks (Walker et al. 2004). The resilience theory tends to run into problems when manipulations to the systems do not allow the system to adapt after disturbances. Disturbances within a system are a part of the system and help provide some of the ecosystem services necessary to the river. It is understood that river basin system are complex with many subsystems. When management practices are implemented to provide a function, the system adjusts to continue to provide its natural services to the degree that it can.
 * Resilience Theory**

A systems ability to be resilient after disturbances has many different factors and variables but the four most critical factors are (Walker 2004):

1) Latitude: the maximum amount a system changes after a disturbance before losing its ability to recover; 2) Resistance: the ease/difficulty for a system to recover after a disturbance; 3) Precariousness: how close is the system currently to a threshold, that will make it difficult or impossible to recover; and 4) Cross-scale relations: how the above three attributes are influenced by (sub) systems at scales above and below the scale of interest.

Walker further explains that the resilience theory starts with some level of a stable landscape as a social economic system (SES). Being able to evaluate all of the attributes together rather than individually would provide a better estimation of a system's resilience. As river systems reach thresholds along their natural order, the system has the potential to recover or change from the disturbance; this is defined as a regime shift (Folke et al. 2004). Adaptive management of systems disrupts the services provided by function groups of species, geomorphology and connection within the ecosystem, creating a barrier for resilience (Folke et al. 2004). This concept provides a connection to the continuum theory. The services provided from feedback that disturbance cause help to strength the responses from the different function groups. The resilience of a system helps to predict system’s thresholds and responses. Adaptive management does not account for the potential of a system to return to steady state destroying the resilience of the system. Adaptive management increases and drives unintended regime shifts in the systems (Folke et al. 2004). Further, an application of resilience theory is the restoration of resilience of a system in order to adapt to the strong human influence projected on ecosystems (Folke et al. 2004). Understanding the connection between regime shifts, functional groups and biodiversity will provide a basis for restoring and managing river systems.

=** Application of Theories **= With the vast amount of purposes for restoration projects along streams and rivers it is difficult to directly link a project with a specific theory. All restoration projects have a theory of improving the system. Evaluating restoration projects has become more and more critical as money continues to be pumped into poorly understood systems. Environmental assessments required by the U.S. Environmental Protection Agency for any action on public land is an excellent start to evaluating the objectives of a restoration project. However, application of methods are not all the same and even in the same reach may not have the same outcome (Davis and Muhlberg 2002). If a system has been manipulated to provide a service for society, it will be difficult to bring that system to a “historic” natural state. Systems of the Southwestern U.S. fall within this category and add to that, the limited supply of water; the river systems have been dammed and diverted to provide a function to water users along the river system A result of this management is channelizing, disconnecting the flood plain, and destroying riparian zones not to mention the changes in chemistry and ecosystems. But the current changes allow for the system to provide water for longer periods of time for agriculture and irrigation, and recreational uses. With the management of these systems, furthermore, cities have built right up to rivers, removing further potential for restoration. The system must adapt to these changes and thus its natural function -- if adaptation can even be reached. Restoration projects do not only have physical restraints but also policy and economic constraints, which are placed on the system due to the social-functions that are the primary purpose of the modern system. Systems in the Eastern and Northeastern United States have many of the same problems but the biggest difference between the two locales is that these systems have considerably more water to deal with. When these systems are manipulated to serve specific functions, natural disturbance can be extremely detrimental; an example of this is the flooding along the [|Mississippi River]. Recent flooding demonstrates the power and destruction that could occur if nature is attempted to be harnessed. Management of river systems has become increasingly more difficult with the number of stakeholders and the increase in restrictions. As the complexity of policy management increases, the potential for the holistic view of services provided by the systems are lost. With shortsighted restoration goals and limited understanding of the full capacity of a system, failure of restoration projects increases, adding to the social view of wasted effort and money. Thinking of restoration projects as an opportunity to better understand a system; would reduce the win/loss image (Jordan //et al.// 1987). Due to strict management, restoration projects tend to have finite end goals not to mention the measurement of these end goals may be difficult to measure. Restoration projects without long-term analysis and management may succeed in the short term and fail in the long term or vise versa (Palmer et al. 1997). Failures in the short term due to the nature of the system potentially could succeed in the long term (Palmer //et al.// 1997). Evaluation criteria for restoration projects that pertain to the system would allow for a more thorough analysis. Funding and project end dates do not dictate the completion of restoration projects. Visual failures of success of projects are not a measurement of projects; this simple ideology and lack of understanding are the primary reasons that ecosystems have to be reevaluated and restored.

The following measurement tools and analysis parameters would help to develop better restoration projects (Palmer et al. 2005):

1) A guiding image exists: A dynamic ecological endpoint is identified and used to guide the restoration; understanding of end points within a restoration project is paramount. Attempting to restore river systems to historic conditions may not be achievable due to the “new” services that the system is supplying. Also, restoring for a single purpose may not restore anything in the long run as is explained in ecosystem services. 2) Ecosystems are improved: the ecological conditions of the river are measurably enhanced: successful restoration projects will have many measurable services improved provided a functioning and restored ecosystem. How much of the system is restored will be a measure of the long term end goal of the project. 3) Resilience is increased: the river ecosystem is more self-sustaining than prior to the restoration: as defined by resilience, how the system is able to return from a disturbance will be a measure of the system resilience. In systems that have large human impacts it will be difficult to restore the system's resilience, but in sub-systems and low human activity systems restoration has a greater potential for returning a system's resilience. 4) No lasting harm is done: implementing the restoration does not inflict irreparable harm. Palmer references Leopold and his first rule of restoration “restoration should do no harm." 5) Ecological assessment is completed: Some level of both pre- and post-project assessment is conducted and the information is made available. As restoration projects are completed there will be both negative and positive outcomes. Measuring the end product with the over arching goals will determine the success of the project. Again referencing Leopold, restoration is more than a project it is an acid test for future projects. Restoration projects are also never completed in the long term, due the human driven functions of the system, the system has to be monitor for its ability to maintain sustainability and resilience. Evaluation standards such as Palmer et al.'s (2005) would provide policy makers and managers a grade sheet to evaluate projects and remove the stigma of money lost and wasted effort of public funds and help justify restoration projects. Not all restoration projects have the same end points and cannot have the same restoration techniques applied. Further, different systems have different functions and services. As environmental restoration moves more into the limelight, it will receive greater and greater criticism. Current ideological practices of ecosystem services will not be sustainable and are becoming detrimental, systematic approaches and analysis will help establish fundamental practices to sustain ecosystems. Palmer’s (2005) evaluation standards may be very difficult to evaluate in the short term and set a high bar for restoration projects to meet. Many restoration projects are for a single or limited number of objectives and not toward a holistic recovery, due to constraints, funding, function, etc. Another set of evaluation standards have been suggested (Kondolf 1995):

1) Clear objectives: provide clear objects as well as a framework for evaluation of the object. 2) Baseline data: is needed of the system to include as long a time scale as possible to be able to evaluate changes caused by the project. 3) Good study design: to demonstrate the effects in a complex system. NEPA is the only environmental tool that requires project managers to put serious thought into the methods and theories they intend to apply. In the end any application to a system is only an experiment. 4) Commitment to the long term: monitoring of the system needs to continue well after the end of the project. Kondolf suggests at least a decade, with the examples that we have today; there may not be a minimum. 5) Willingness to acknowledge failures: an understanding that a restoration project in only an experiment and will provide valuable knowledge, data and learning for managers and policy makers to utilize to make better decisions.

Evaluations of projects will solidify the basic understanding that restoration is a an acid test or experiment that needs to have many different inputs. Broad based theories for single purpose projects and single based projects with out any logical theory applied could create an even more devastating out come that was started with. Current management practices and structures are not natural but serve a purpose for humanity and the acknowledgement that society is apart and not a part of the ecosystem.

=**Conclusion**= What have we learned from management of river systems? Has our management provided a better service of the system and the intended function? Due to the realization by society that restoration of our river systems is necessary, the answer is no. The new question is: will our restoration project improve the situation or reset and amplify the current situation? Research has demonstrated that basic understandings of the system we are intending to manipulate is necessary. Just because humanity can harness a natural system, does not mean that it is a good idea or that they have actually succeeded. Broad theories establish a foundation that restoration and management projects can be built upon, but evaluation and monitoring has to be included. As systems begin to fail, management has to be altered to maintain the existence of the system. If to many regime shifts are crossed a systems ability to recover may not exist, removing that systems ability to provide the intended function.

There is not a simple answer to restoration. Three practices need to be included in all restoration projects with the understanding that the methods will change in order to have a successful project; baseline analysis, monitoring and adaptive management (Choi 2004, Kondolf 1995 and Palmer et al. 1997). These three practices are the foundation of most theories, and should be applied to restoration and implemented into management plans. Adaptive management applies theory to goals, techniques, and monitoring of restoration projects. In conclusion restoration experiments as acid tests for improving our environment will always be evolving and strengthening our knowledge base.

In many cases, yes, if the intended functions were water delivery, flood control, power production, etc: Dr. Stone, one of the big arguments of the paper is that the antique idea of engineering the system to only service a purpose for humanity is the reason why we are having to restore the system. Eco-engineering and resilience theory address the need to restore systems and include the influence of humanity, because we aren’t going away. An understanding from your class is that the system may serves a function but is it for the betterment of the system or can the system sustain itself to serve that function?


 * References **

Choi, Y. D. 2004. Theories for ecological restoration in changing environment: Toward ‘futuristic’ restoration. Ecological Research (2004) 19: 75-81.

Davis, J. C. and Muhlberg, G. A. 2002. The evaluation of wetland and riparian restoration projects. Alaska Department of Fish and Game, Habitat and Restoration Division, Anchoarge, AK. April 2002

Folke, C., Carpenter, S., Walker, B., Scheffer, M., Elmqvist, T., Gunderson, L., and Holling, C.S. 2004. Regime shifts, Resilience, and Biodiversity in ecosystem management. Annu. Rev. Ecol. Evol. Syst. 2004.35, pp 557-581. August 5, 2004.

Jordan III, W. R., Gilpain, M.E., and Aber, J. D., Eds. 1987. Restoration ecology a synthetic approach to ecological research. Cambridge, New York, 3-21.

Kondolf, G. M. 1995. Five Elements for effective evaluation of stream restoration. Restoration Ecology vol 3 no 2, pp 133-136, June 1995.

Lake, P.S., Bond, N., and Reich, P. 2007. Linking ecological theory with stream restoration. Freshwater Biology 52, 597-615.

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Mitsch, W. J. and Jorgensen, S. E. 2003. Ecological engineering: A field whose time has come. Ecological Engineering 20, 363-377.

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Palmer, M. A., Ambrose, R. G., and Poff, N. L. 1997. Ecological Theory and Community Restoration Ecology. Restoration Ecology Vol 5 No 4, 291-300.

Palmer, M.A., Bernhart, E.S., Allan, J. D., Lake, P.S., Alexander, G., Brooks, S., Carr, J., Clayton, S., Dahm, C. N., Follstad Shah, J., Galat, D. L., Loss, S. G., Goodwin, P., Hart, D.D., Hassett, B., Jemkinson, R. Kondolf, G.M., Lave, R., Meyer, J.L., O’Donnell, T.K., Pagano, L. and Sudduth, E. 2005. Standards for ecologically successful river restoration. Journal of Applied Ecology 2005 42, 208-217.

US Environmental Protection Agency. 2008. Handboook for Developing Watershed Plans to Restore and Protect our Waters. Office of the Water, Nonpoint source Control Branch. EPA 841-B-08-002. March 2008.

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