Resilience (ecology)

The concept of resilience refers in ecosystem theory, the ability of an ecosystem in the face of environmental disturbances to maintain its basic organizational manner rather than go into a qualitatively different system state. As a slogan with different theoretical definitions and interpretations relating to resource use resilience has become a central stability concept in ecology, ecosystem theory and especially the environmental research.

Background

A native of the psychology term resilience is often equated with the " Abfederungsvermögen " of systems against external disturbances. The concept of resilience was introduced in the 1970s by Holling in the ecology The idea of resilience of ecological and social systems remained increasingly from the 1990s through.

Definition

A unified basic understanding of the precise definition and meaning of the " concept of resilience " forms in the scientific debate (July 2012) only slowly. The term is often used in social-ecological approaches, what the original ecosystem narrower definition of Ellenberg increasingly expanded.

Heinz Ellenberg defines the resilience of ecosystems as follows:

" ' Resilience ' is the ability after major species shifts ( eg, from herbaceous to forest communities ) through a more or less long-term return succession ( succession ) of other ecosystems back to the original species assemblage."

The problem with the scientific and ecological consideration Resilienzbegriff is the definition of the ground state and the criteria (parameters) for determining whether an ecosystem that is changing due to disturbances beihält its basic organizational manner or not. The resilience concept is in contrast to the existing as dogma in the 70 years the concept of "ecological balance ". The contrary is the resilience research today of dynamic systems, which can develop in different directions (succession in different directions ).

Which state is considered as "valuable " is based resilience Idea consequence on human attribution of value and can not be determined by ecological knowledge alone. Resilient ecosystem states can not be considered per se as 'good' or useful (see problem complex nature rating - social models; see savannah example). Resilience evaluates the considered states of nature from an individually culturalist rather than a strictly naturalistic point of view.

The resilience lined up a nature related to the use of concepts of sustainability. Resilience approaches are discussed mainly for cultural ecosystems. This is particularly true in the light of "climate plasticity " of cultural ecosystems that are threatened by climate change from a variety of biotic and abiotic calamities.

Examples

Regeneration of forests

Overexploitation of forests leaves most ecologically impoverished, often quilted, karst areas without the power of self- regeneration. One then speaks of the Raubbausyndrom. The resilience can be lost even with the falls below a minimum diversity of species.

Of particular importance is the resilience to silviculture. The dominant mode shape of the age -class forest tends in any serious disorder ( biotic or abiotic calamities ) for the areal destruction, so the bald spot, which corresponds to the total loss of the forest ecosystem. In continuous forest, however, the regular multi-layered forest structure is retained even after heavy calamities essentially without any replanting on a bald spot after the calamity is necessary. He has thus, in contrast to the age -class forests the ability to resilience.

Regeneration overgrazed grasslands

Some ecosystems, such as heavily grazed savannas already can be very resilient, ie they bear a high number and strength of ecological disturbances (eg, fire, etc. ) without having to move to a different system state represented by other ' slow ' variables is determined. This condition thus has a very high self-regeneration, in the sense that it maintains itself even at high disturbance intensities or re- established. In contrast to a non- grazed savanna, a heavily grazed savanna therefore " more resilient " (i.e., in this case, interference resistant ).

Marine ecosystems

In marine ecosystems, the resilience is interesting on several spatial and taxonomic levels: Can coral reefs evolutionarily adapt quickly to rapidly for them water temperature fluctuations, and under what circumstances, fish stocks recover in different sea areas? Especially for the use of the resource fish are resilience issues of importance.

Fields of application

Human influences in ecosystems that are being explored with resilience theoretical approaches are for example:

• Intensive agriculture
• Over-exploitation of forests
• Marine ecosystem complexes ( tropical coral reefs, seagrass forests etc. )
• Overfishing
• Waste in marine systems
• Pollutants in marine systems
• Eutrophication of marine and limnic systems

Criticism

The approach behind it is that of adaptation. Against the background of global change through economic and climate-related factors, the resilience research assumes that systems have to adapt. Critics accuse her to take environmental changes back and "make the best of it " from an opportunistic attitude.

Research

International significance of the Stockholm Resilience Center, the foundation was as an independent research institute at the University of Stockholm in 2007. MISTRA The Foundation (the Foundation for Strategic Environmental Research ) is behind the center and it funded until 2013.

The term and complex issues Resilience takes in research and sustainability research socio-ecological one an increasingly larger space.