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Ecosystem management

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Prescribed burning is an ecosystem management approach, with indirect benefits to society via the maintenance of ecosystem services and the reduction of severe wildfires.[1]

Ecosystem management is an approach to ecosystem maintenance and restoration that aims to promote the long-term sustainability of ecosystem functioning and thus, meet socioeconomic, political, and cultural needs by ensuring the persistence of ecosystem services.[2][3][4] Building upon traditional natural resource management approaches, ecosystem management, which integrates ecological, socioeconomic, and institutional priorities, is a holistic, adaptive method for evaluating and achieving ecosystem resilience and sustainability.[2][4][5]

Formulations

The term “ecosystem management” was formalized in 1992 by F. Dale Robertson, who was at that time the Chief of the U.S. Forest Service. Robertson stated, “By ecosystem management, we mean an ecological approach… [that] must blend the needs of people and environmental values in such a way that the National Forests and Grasslands represent diverse, healthy, productive and sustainable ecosystems.”[6] A variety of additional definitions of ecosystem management exist, although definitions of this concept are typically vague.[5]

Robert T. Lackey defined ecosystem management as, "the application of ecological and social information, options, and constraints to achieve desired social benefits within a defined geographic area and over a specified period."[5] F. Stuart Chapin and coauthors define it as, "the application of ecological science to resource management to promote long-term sustainability of ecosystems and the delivery of essential ecosystem goods and services,"[7] while Norman Christensen and coauthors define it as, "management driven by explicit goals, executed by policies, protocols, and practices, and made adaptable by monitoring and research based on our best understanding of the ecological interactions and processes necessary to sustain ecosystem structure and function."[8] Peter Brussard and colleagues defined it as "managing areas at various scales in such a way that ecosystem services and biological resources are preserved while appropriate human use and options for livelihood are sustained."[9]

Several core principles define and bound the concept and provide operational meaning:

  1. ecosystem management reflects a stage in the continuing evolution of social values and priorities; it is neither a beginning nor an end;
  2. ecosystem management is place-based and the boundaries of the place must be clearly and formally defined;
  3. ecosystem management should maintain ecosystems in the appropriate condition to achieve desired social benefits;
  4. ecosystem management should take advantage of the ability of ecosystems to respond to a variety of natural and man-made stressors, but all ecosystems have limited ability to accommodate stressors and maintain a desired state;
  5. ecosystem management may or may not result in emphasis on biological diversity;
  6. the term sustainability, if used at all in ecosystem management, should be clearly defined—specifically, the time frame of concern, the benefits and costs of concern, and the relative priority of the benefits and costs; and
  7. scientific information is important for effective ecosystem management, but is only one element in a decision-making process that is fundamentally one of public and private choice.[5]

A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[7] "intergenerational sustainability [is] a precondition for management, not an afterthought".[8] Ideally, there should be clear, publicly-stated goals with respect to future trajectories and behaviors of the system being managed. Other important requirements include a sound ecological understanding of the system, including connectedness, ecological dynamics and the context in which the system is embedded. An understanding of the role of humans as components of the ecosystems and the use of adaptive management is also important.[8] While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[8] (see, for example, agroecosystem and close to nature forestry).

As a concept of natural resource management, ecosystem management remains both ambiguous and controversial, in part because some of its formulations rest on policy and scientific assertions that are contested.[10] These assertions are important to understanding much of the conflict surrounding ecosystem management. Professional natural resource managers, typically operating from within government bureaucracies and professional organizations, often mask debate over controversial assertions by depicting ecosystem management as an evolution of past management approaches.

History

Pre-Industrialization

Sustainable ecosystem management approaches have been used by societies throughout human history. Prior to colonization, Indigenous cultures often sustainably managed their natural resources through intergenerational Traditional Ecological Knowledge (TEK). In this approach, cultures acquired knowledge of their environment over time and this information is passed on to future generations through cultural customs, including folklore, religion, and taboos.[11][12] Traditional management strategies vary by region and examples include the burning of the longleaf pine ecosystem by Native Americans in what is today the southeastern United States;[13] the ban of seabird guano harvest during the breeding season by the Inca;[14] the sustainable harvest practices of glaucous-winged gull eggs by the Huna Tlingit;[15] and the Maya milpa agroforestry approach, which is still used today.[16]

Post-Industrialization

In industrialized Western society, ecosystems have been managed primarily to maximize yields of particular natural resource.[17] This method to managing ecosystems can be seen by the U.S. Forest Service's shift away from sustaining ecosystem health and toward maximizing timber production to support residential development following World War II.[18] Further, underlying traditional natural resource management is the view that each ecosystem has a single equilibrium and minimizing variation around this equilibrium results in more dependable maximal yields of natural resources.[19][12] For example, this perspective informed the long-held belief in forest fire suppression in the United States, which has driven a decline in populations of fire-tolerant species as well as fuel buildup, leading to higher intensity fires.[1] Additionally, traditional approaches to managing natural systems tended to be site- and species-specific, rather than considering all components of an ecosystem collectively; employ a “command and control” approach; and exclude stakeholders from management decisions.[4]

The latter half of the 20th century saw a paradigm shift in how ecosystems were viewed, with a growing appreciation for the importance of disturbance and for the intrinsic link between natural resources and overall ecosystem health.[17] Simultaneously, there was acknowledgement of the reliance of society on ecosystem services, beyond provisioning goods, and of the inextricable role human-environment interactions play in ecosystems.[20][21] In sum, ecosystems were increasingly seen as complex systems, shaped by non-linear processes, and thus, they could not be managed to achieve a single, predictable outcome.[19] As a result of these complexities and often unforeseeable feedbacks from management strategies, DeFries and Nagendra deem ecosystem management to be a “wicked problem”.[17] Thus, the outcome of traditional natural resource management's "evolution" over the course of the 20th century is ecosystem management, which explicitly recognizes that technical and scientific knowledge, though necessary in all approaches to natural resource management, are insufficient alone.[4]

Stakeholders

Stakeholders are individuals or groups of people who have an interest in or are affected by policy or management decisions and actions, but they also may have power to influence the goals, policies, and decisions relating to ecosystem management.[22] The complex nature of decisions made in ecosystem management, from local to international scales, requires stakeholder participation with a diversity of knowledge, perceptions, and values of nature.[23][24] Stakeholders will often have different interests in ecosystem services.[25] This means that effective management of ecosystems requires a flexible management process that develops mutual trust in issues of common interest with the objective of creating mutually beneficial partnerships.[26]

Approaches to ecosystem management

Several approaches to implementing the maintenance and restoration of natural and human-modified ecosystem exist. Command and control management and traditional natural resource management are the precursors to ecosystem management, whereas adaptive management, strategic management, and landscape-level conservation represent different strategies and processes involved in implementing ecosystem management:[4]

Command and control management

The wolf pack in Slough Creek, Yellowstone, runs away over the frozen ground. The black wolf is the alpha male.

Command and control management utilizes a linear problem solving approach where a perceived problem is solved through controlling devices such as laws, threats, contracts and/or agreements.[19] This top-down approach is used across many disciplines and works best with problems that are relatively simple, well-defined and work in terms of cause and effect and for which there is broad societal agreement as to policy and management goals.[27] The application of command and control management has often attempted to control nature in order to improve product extractions, establish predictability and reduce threats.[19] Command and control strategies include the use of herbicides and pesticides to improve crop yields;[19] the culling of predators to protect game bird species;[28] and the safeguarding of timber supply, by suppressing forest fires.[1]

However, due to the complexities of ecological systems, command and control approaches may result in unintended consequences.[4] For example, wolves were extirpated from Yellowstone National Park in the mid-1920s to regulate elk predation. Long-term studies of wolf, elk, and tree populations since wolf reintroduction in 1995 demonstrate that reintroduction has decreased elk populations, improving tree species recruitment.[29] Thus, by controlling ecosystems to limit natural variation and increase predictability, command and control management often leads to a decline the resilience of ecological, social, and economic systems, termed the “pathology of natural resource management”.[19] In this “pathology”, an initially successful command and control practice drives relevant institutions to shift their focus toward control, over time obscuring the ecosystem’s natural behavior, while the economy becomes reliant on the system in its controlled state.[4] Consequently, there has been a transition away from command and control management and increased focus on more holistic adaptive management approaches and arriving at management solutions through partnerships between stakeholders.[27]

Natural resource management

Main article: Natural resource management

The term natural resource management is frequently used when dealing with a particular resource for human use rather than managing the whole ecosystem.[30] A main objective of natural resources management is sustainability for future generations. One method to achieve this is by appointing ecosystem managers to balance natural resources exploitation and conservation over a long-term timeframe.[31] The balanced relationship of each resource in an ecosystem is subject to change at different spatial and temporal scales.[32] Dimensions such as watersheds, soils, flora, and fauna need to be considered individually and on a landscape level. A variety of natural resources are utilized for food, medicine, energy and shelter.[33]

The ecosystem management concept is based on the relationship between sustainable resource maintenance and human demand for use of natural resources.[32] Therefore, socioeconomics factors significantly affect natural resource management.[30] The goal of a natural resource manager is to fulfill the demand for a given resource without causing harm to the ecosystem, or jeopardizing the future of the resource.[34] Partnerships between ecosystem managers, natural resource managers and stakeholders should be encouraged in order to promote a more sustainable use of limited natural resources.[35] Natural resource managers must initially measure the overall condition of the ecosystem they are involved in. If the ecosystem's resources are healthy, managers can decide on the ideal amount of resource extraction, while leaving enough to allow the resource to replenish itself for subsequent harvests.[34] Historically, some natural resources have experienced limited human disturbance and therefore have been able to subsist naturally. However, some ecosystems, such as forests, which typically provide considerable timber resources; have sometimes undergone successful reforestation processes and consequently have accommodated the needs of future generations. A successfully managed resource will provide for current demand while leaving enough to repopulate and provide for future demand.

Human populations have been increasing rapidly, introducing new stressors to ecosystems, such as climate change and influxes of invasive species. As a result, the demand for natural resources is unpredictable.[33] Although ecosystem changes may occur gradually, the cumulative changes can have negative effects for humans and wildlife.[31] Geographic Information Systems (GIS) and Remote Sensing Applications can be used to monitor and evaluate natural resources by mapping them in local and global scales. These tools will continue to be highly beneficial in natural resources management.[32]

Adaptive management

Adaptive management is based on the concept that predicting future influences/disturbance to an ecosystem is limited and unclear.[36] Therefore, the goal of adaptive management is to manage the ecosystem so it maintains the greatest amount of ecological integrity, but also to utilize management practices that have the ability to change based on new experience and insights.[37][36]

Adaptive management aims to identify uncertainties in the management of an ecosystem while using hypothesis testing to further understand the system.[38] In this regard, adaptive management encourages learning from the outcomes of previously implemented management strategies.[36] Ecosystem managers form hypotheses about the ecosystem and its functionality and then implement different management techniques to test the hypotheses.[39] The implemented techniques are then analyzed to evaluate any regressions or improvements in functionality of the ecosystem caused by the technique.[39] Further analysis allows for modification of the technique until it successfully meets the ecological needs of the ecosystem.[37] Thus, adaptive management serves as a “learning by doing” method for ecosystem management.

Adaptive management has had mixed success in the field of ecosystem management, fisheries management, wildlife management, and forest management, possibly because ecosystem managers may not be equipped with the decision-making skills needed to undertake an adaptive management methodology.[40] Additionally, economic, social and political priorities can interfere with adaptive management decisions.[40] For this reason, adaptive management to be successful must be a social process as well as a scientific one, focusing on institutional strategies while implementing experimental management techniques.[38]

Strategic management

Main article: Strategic management

Strategic management encourages the establishment of goals that will sustain the ecosystem while keeping socioeconomic and politically relevant policy drivers in mind.[3] Strategic management differs from other types of ecosystem management because it keeps stakeholders involved and relies on their input to develop the best management strategy for an ecosystem. Similarly to other modes of ecosystem management, this method places a high level of importance on evaluating and reviewing any changes, progress, or negative impacts and prioritizes flexibility in adapting management protocols as a result of new information.[41]

Landscape level conservation

Landscape level conservation is a method that considers wildlife needs at a broader landscape level scale when implementing conservation initiatives.[42] This approach to ecosystem management involves the consideration of broad scale interconnected ecological systems that acknowledges the whole scope of an environmental problem.[32] In a human-dominated world, weighing the landscape requirements of wildlife versus the needs of humans is a complicated matter.[43]

Landscape level conservation is carried out in a number of ways. A wildlife corridor, for example, is a connection between otherwise isolated habitat patches that are proposed as a solution to habitat fragmentation.[44] In some landscape level conservation approaches, a key species vulnerable to landscape alteration is identified and its habitat requirements are assessed in order to identify the best option for protecting their ecosystem.[45] However, lining up the habitat requirements of numerous species in an ecosystem can be difficult, which is why more comprehensive approaches to further understand these variations have been considered in landscape level conservation.[46]

Human-induced environmental degradation is an increasing problem globally, which is why landscape level ecology plays an important role in ecosystem management.[47] Traditional conservation methods targeted at individual species need to be modified to include the maintenance of wildlife habitats through consideration of both human-induced and natural environmental factors.[47]

See also

References

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