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'''Resilience and resistance'''
  
Multifunctionality and Valuation in coastal zones: concepts, approaches, tools and case studies
 
  
The thematic ENCORA network on Multifunctionality and Evaluation (2006-2009) was established to address a twofold challenge: putting into evidence the problems arising from different and conflicting interests, pressures and impacts which originate from social and economic activities on coastal areas and discussing strategies for the integration of these conflicting interests into [[Integrated Coastal Zone Management (ICZM)|coastal management]] and decision making processes. The network focused on the following topics:
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{{Definition|title=Resistance
* the definition of basic concepts underlying different evaluation approaches
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|definition= The capacity to weather a disturbance without loss <ref name=L>Lake, P.S. 2013. Resistance, Resilience and Restoration. Ecological Management and Restoration 14: 20-24</ref>. }}
* the description of different approaches at the basis of evaluation strategies, and of
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{{Definition|title=Resilience
* tools and methodologies which can be applied to the evaluation in coastal zone management contexts.
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|definition= The capacity to recover from a disturbance after incurring losses <ref name=L></ref>. }}
* case studies that provide examples of application of various methodologies.
 
  
  
==Rationale of the thematic network==
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==Introduction==
Coastal zones include numerous different functions and uses which depend on the same limited resources and space. This fact frequently generates conflicts between different types of use. Furthermore, interventions regarding single functions of a [[coastal zone]] usually have important impacts on other uses within same area or on a vaster territorial scale. Impacts which [[Climate adaptation policies for the coastal zone|climate change]] is expected to have on Europe's are going to accentuate existing and create new conflicts among uses. Sustainable decision making and management in such multifunctional areas thus requires the capacity to consider all different economic and social spheres contemporaneously asks for the integration of different interests into the decision making process.  
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Coastal and marine [[ecosystems]] are affected by environmental disturbance at a variety of spatio-temporal scales. The organisms inhabiting these systems are adapted to such disturbance, either by being tolerant of these conditions or by playing a role in one or more of the successional stages that follow during ecosystem recovery.
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[[Image:Uses1.jpg|thumb|left|]]
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If all species in the system were tolerant to a particular perturbation, very little would change at the ecosystem level, and we could call the system resistant to this disturbance. However, often a disturbance, such as a temporary very low oxygen level, affects a substantial proportion of the organisms dramatically, either causing them to die, or forcing them to rapidly migrate to more favorable parts of the environment. Such a catastrophic disturbance could locally defaunate a certain volume in the pelagic or a certain area of hard or soft substrate. Such destruction at a local scale does not mean the end of local functioning; Usually organisms are available at a larger spatial scale that can re-colonize the affected area, according to their particular tolerances and abilities to favorably affect their local environment. The term resilience has been used in different ways, first of all for the rate of recovery to the previous state and secondly for the system's ability to re-organize itself. Both resistance and resilience cause an [[ecosystem]] to remain relatively unchanged when confronted by a disturbance, but in the case of resistance no internal re-organization and successional change is needed. In contrast, resilience implies that the system is internally re-organizing, perhaps through a mozaic of patches that are at different stages of re-assembly.
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When considering the potential effect of a certain type of disturbance it is thus useful to ask two questions: (1) Will the species of this system be able to tolerate it (implying resistance), and if not, (2) Is recovery possible through a successional trajectory, back to the same, or at least a desirable, ecosystem state (implying resilience)? It should be clear that the system will not be sufficiently resistant when (even gradual) uni-directional change acts faster than the organisms' ability to adapt their tolerances. If uni-directional gradual change is this fast, the system will not be sufficiently resilient either, as full recovery through succession will then not be possible. Recovery from sudden and local disturbance is usually possible through re-colonization, but the rate of recovery will depend tremendously on the spatial extent of disturbance. For example, recovery from anoxia could take 5 to 8 months at the scale of square meters (Rossi et al. 2009<ref>Rossi, F., Vos, M. & Middelburg, J.J. Species identity, diversity and microbial carbon flow in reassembling macrobenthic communities. Oikos 118:503-512.</ref>), but could take 5 to 8 years at the scale of a whole bay(Diaz & Rosenberg 1995<ref>Diaz, R.J. & Rosenberg, R. 1995. Marine benthic hypoxia: a review of its ecological effects and the behavioural responses of benthic macrofauna. Oceanogr. Mar. Biol. Annu. Rev. 33:245-303.</ref>).      
  
In this context, evaluation approaches offer tools and methodologies which allow the description, analysis and assessment of coastal systems, using rational and systematic procedures. Furthermore these approaches include the possibility of confronting interests and values of different users and actors coming from different economic and social areas on the basis of criteria and indicators for establishing hierarchies of values or for translating values into terms which can be understood by all actors. Using evaluation and assessment techniques, information is provided which can support shared decision making confronting interests of different stakeholders and users of the coastal area in a co-ordinated and rational manner.
 
  
[[Evaluation]], understood as a means of informing decision making, is of crucial importance for introducing multifunctionality aspects into coastal zone management. Albeit their great potential, evaluation techniques and integrated decision making are still scarcely employed in European coastal zone management. It is desirable that the development of tools facilitating the multifunctional challenge represented by [[coastal zone]]s should be brought further by a collaboration between scientists and practitioners and their use promoted further among coastal zone managers. Considerable progress can be made at the European level by networking activities to spread existing examples of good practice and research amongst European partners.
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while [[resilience]] has been defined in different ways: it can be a measure for the speed at which an [[ecosystem]] returns to its former state following a (minor) disturbance. The idea is that a system with a short return time is more resilient than one with a long return time. Such resilience measured as (1 / the return time to a stable equilibrium) has also been called ''engineering resilience''. It has however a long history of use among ecologists (Pimm 1982<ref>Pimm, S.L. 1982. Food Webs. The University of Chicago Press.</ref>, DeAngelis 1992<ref>DeAngelis, D.L. 1992. Dynamics of Nutrient Cycling and Food Webs. Chapman and Hall, London.</ref>, Vos et al. 2005<ref>Vos, M., Kooi, B.W., DeAngelis, D.L. & Mooij, W.M. Inducible defenses in food webs. In: Dynamic Food Webs. Multispecies Assemblages, Ecosystem Development and Environmental Change. Eds. P.C. de Ruiter, V. Wolters & J.C. Moore. Academic Press. Pp. 114-127.</ref>). It is also used in a way that more closely resembles the definition of resistance. Ecological resilience ... (cite Gunderson 2000<ref>Gunderson, L.H. 2000. Ecological Resilience - in Theory and Application. Annual Review of Ecolog and Systematics 31:425-439.</ref> to avoid confusion)
  
== Concepts ==
 
The definition of some basic concepts underlying evaluation approaches has been considered useful for the understanding of the proposed approaches and methodologies. These definitions consider the relationship between multifunctionality on the one side, being one of the characteristics of coastal areas which represent a major challenge for sustainable decision making and management, and evaluation on the other side, which can be used as a support for decision making in complex and multifunctional contexts.
 
  
A second important definition regards the term '''value''', as evaluation is used to attribute values to different options or to base decision making on rational judgements. In this context, the term [[economic value]] represents one of the basic concepts which allow for the adoption of a common measure for most of the values expressed by different actors.
 
  
Although [[economic value]] represents an important concept for the measurement of the value  society attributes to a certain asset, some values may not be adapted to being measured directly in terms of market values, as they refer to objects which normally are not treated on markets. In those cases, the extension of the concept of value beyond the worth expressed by market values becomes relevant, introducing a concept of value which comprises, according to the theory of welfare economics, the benefit individuals derive from economic goods or services which not necessarily corresponds to the market value. The introduction of concept of individual benefit as a measure of social value allows for the evaluation of goods and services which cannot be exchanged on markets, such as natural resources. One of the most relevant concepts in this context is represented by the [[Non-use value: bequest value and existence value|existence value]] which expresses the benefit individuals gain from the existence of goods which are not used directly independent of present or future uses that will be made of these assets, allowing thus to introduce the value of the existence of categories as natural resources [[Defining marine biological value|biodiversity]] etc. into monetary evaluations.
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Coastal systems are naturally resilient. ... This article will discuss. In particular it will argue that ...  
  
Whereas accurate measurement of values will be adequate in some cases of evaluation, not all values can be revealed with a congruent effort. In order to facilitate monitoring and decision making processes of complex contexts, [[indicators]] based on data easy to access or to measure are used. A concept which is commonly measured by indicators is represented by [[sustainable|sustainability]], where aggregated judgements on the performance of many different entities with respect to one option have to be produced, leading to the definition of specific sets of [[sustainability indicators]] which allow also for international confrontation of performances.  
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[[Biodiversity]] allows ecosystems to adapt to changing conditions. Humans, however, have acted to increase the rate of change and consequently, it will be a great challenge for the marine environment to adapt rapidly enough in the future. These changes have been induced through pollution, fishing, [[sediment]] deposition and alteration of the global climate. Without genetic diversity, natural selection cannot occur and natural selection is limited, then adaptation is impossible. It is evident that the preservation of biodiversity and, more specifically, genetic diversity is of paramount importance for successful adaptation to our rapidly changing environments.
  
Some impacts from human activities are not continuous, but may occur only with a certain probability and a certain variance in the entity of damages caused. The concept of [[Environmental risk assessment of marine activities|risk analysis]] introduces the concept of considering and quantifying aspects of uncertainty in order to integrate them into evaluation.
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Biodiversity may not act as a protect ecosystems from major abiotic disturbances
The concept of [[Carrying capacity analysis|carrying capacity]] finally is based on the notion that [[ecosystems]] have a limited capacity of coping with environmental stresses. Approaches based on this concept point to a quantification of limits for socio-economic uses with respect to coastal systems, as for instance, tourism.
 
  
== Approaches ==
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for Biodiversity: cite: Folke et al. 2004<ref>Folke, C., Carpenter, S., Walker, B., Scheffer, M., Elmqvist, T., Gunderson, L. & Holling, C.S. 2004. Regime Shifts, Resilience, and Biodiversity in Ecosystem Management. Annual Review of Ecolog and Systematics 35:557-581.</ref>
Based on the different concepts of values described, different approaches are applied to their assessment. As market values can easily be revealed and used for cost-benefit analyses those approaches based on market values represent the most common ones among evaluation approaches and have become quite widespread for the assessment of efficiency of an intervention.  
 
  
Cost benefit analysis, based on monetary measurement, can also be applied on the combined evaluation of values based on market values and non market values. In these cases different approaches can be applied to translate non market – values into monetary terms, in order to include the relative values in the cost-benefit analysis (for further detais see [[Socio-economic evaluation]]). Those approaches are based on the assumption that market goods, properly analyzed, can reveal preferences consumers have with regards to non – market goods. In this way an approximation of the social value attributed to a protected area can be elicited by a computation of expenses tourist make to visit the area or by the [[Hedonic Evaluation Approach|hedonic analysis]] of housing prices in the surroundings of the park. Whereas in this case as well as in the case of housing prices, the value of natural resources is derived from consumer preferences expressed (stated) on the market, a second category of expressions of consumer’s preferences regards the revealed preferences, as for instance the consumer’s (hypothetic) willingness to pay for a service or a good elicited with the help of questionnaires.
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==Resilience through re-colonization==
  
In those cases where monetary values elicited in an indirect way do not represent a suitable scale for measurement, values can be expressed in terms of “preferences”, within approaches based on expert judgements and using techniques which allow for the comparison of multiple different criteria without a common measure.
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To understand resilience of ecosystems it is essential to understand what drives succession within these ecosystems. Succession determines how, and how fast, communities return back to their original state, or perhaps enter a new state. many aspects of succession can be understood in terms of trade-offs between the ability to be either a good early (re-)colonizer, or a good competitor (r-species versus a K-species). Succession involves a gradual replacement of species that differ in these traits and that differ in the degree they tolerate, facilitate or inhibit certain environmental conditions and other species. ... see (Rossi et al. 2009<ref name ="rossi">).Rossi, F., Vos, M. & Middelburg, J.J. 2009. Species identity, diversity and microbial carbon flow in reassembling macrobenthic communities. Oikos, Early View, (January issue).</ref>)
Each of these three principal approaches to evaluation are described in a section.
 
  
== Tools and methodologies ==
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We could thus also call a system resilient when it is organized in such a way that succession leads to a recovery of the original state.
The section tools and methodologies gives an overview on the state of the art in terms of tools for evaluation and assessment to be used in multifunctional coastal contexts. A specific attention has been paid to those tools which are able to integrate between different sectors and give account of different types of values, integrate broader social and economic aspects into project evaluations as in the case of [[regional economic accounting methods]]. The group of tools, based on the use of economic accounting at different spatial levels, is able to assess the economic impact generated by existing or planned activities of by foreseen events on the regional economic structure, basing the analysis on [[input-output matrix]]es of goods and services, [[supply chain analysis]] or on [[computable general equilibrium]] (CGE) models.  
 
  
A further group of tools presented refers to approaches based on monetary valuation of non market values, either on the basis of stated [[Contingent Valuation Method]] or revealed preferences, as in the case of [[Hedonic Evaluation Approach|Hedonic Evaluation Approaches]] which use the decomposition of composite market values in order to estimate the component related to natural resources, or methods of [[Travel cost method|travel cost analysis]] which base the estimation of values of natural resources on the expenses made by individuals who make use of them for leisure time activities.
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==Resilience and nutrient inputs==
For each of these tools a short description is made which helps to understand the use and the possible outcomes of the technique, and further readings are indicated for studies in detail of the applications.
 
 
The application of these evaluation techniques may be quite expensive in terms of time and data requirement, as direct investigation with the help of questionnaires is required. An alternative to direct evaluation is represented by tools which facilitate the [[Value Transfer|use of existing valuations to new evaluations]]. These tools can be used if data is available from sites with similar characteristics to those of the situation to be examined and allow for the transfer of values estimated in one site to another one.
 
  
Further tools for evaluation make use of [[Multicriteria techniques]], which allow for an assessment of policy options based not only on cost-benefit or cost-efficiency criteria, but also on non monetary values or on preferences. An important element of these instruments is the choice of criteria, which have to be shared and understood by all actors, using either predefined sets of criteria such as [[sustainability indicators]] or developing proper sets of criteria to be applied to the problem or development at the stake in the specific decision making process. Therefore the involvement of stakeholders is essential, as the participation of possibly all relevant actors into the decision making process can provide for sustainable and shared decisions. The application of multicriteria techniques is thus strongly connected to tools for [[stakeholder analysis]], as a preparatory tool in decision making processes. Further applicative tools in this sector are deliberation and decision support tools as well as knowledge mediation tools, which assist in structuring and informing decision making processes.
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DeAngelis et al. 1989<ref>DeAngelis, D.L., Bartell, S.M. & Brenkert, A.L. 1989. Effects of nutrient recycling and food chain length on resilience. American Naturalist 134: 778-805.</ref> showed in their analysis of a food chain model that resilience, measured as (1/return time), increased smoothly with nutrient enrichment. The idea is that the system can more quickly return to its original state when the nutrient input is high. However, this result depends on the exact shape of the functional response, the way predators consume their prey as a function of prey density. DeAngelis et al. had used a highly stabilizing Type III (a sigmoid-shaped) functional response. Such a functional response is realistic for learning predators and those that switch between different prey types. Vos et al. 2005<ref>Vos, M., Kooi, B.W., DeAngelis, D.L. & Mooij, W.M. 2005. Inducible defenses in food webs. In: Dynamic Food Webs. Multispecies Assemblages, Ecosystem Development and Environmental Change. Eds. P.C. de Ruiter, V. Wolters & J.C. Moore. Academic Press. Pp. 114-127. </ref> found that resilience (1/return time) would first increase, but then decrease again under nutrient enrichment, when a Type II functional response was used in the model. Many species of consumers throughout the animal kingdom consumer their resources with such a functional response, where intake rate first increases, and then gradually levels off with resource density. Food chains with such consumers would be much less resilient under a high pressure of nutrient  enrichment.      
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Information to be used in decision making processes is highly complex because of the variety of sectors to be considered as well as because of the complexity of single phenomena. Integrated System Frameworks help representing the links between causes, effects and reactions, facilitate the understanding of problems and assist and inform the choice of indicators for evaluation and monitoring (for further details see [[Policy instruments for integrated coastal zone management]])..  
 
  
== Case studies ==
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==Resistance to changes in abiotic and biotic factors==
Case studies can provide a valuable source of information on possible applications of tools and approaches and to guide future studies across Europe. The collection of case studies presented gives an illustration of strategies for evaluating impacts from different socio-economic uses in [[coastal zone|coastal zones]], as for instance from [[Impacts caused by increasing urbanization|urbanization]] which represents one of the most relevant pressure on Mediterranean [[coastal zone|coastal zones]]. The study describes different approaches to evaluation of impacts of urbanization on values of coastal landscapes, on the benefits of property owners and of simple users of coastal zonesand concludes with suggestions for policy options apt to tackle this challenge. The case study on [[impacts from maritime transport]] presents the main findings of a large-scale [[Contingent Valuation Method|contingent valuation]] survey conducted after the Prestige [[oil spills|oil spill]] onto the north-western Spanish coast, considering mainly passive use value lost due to the [[oil spills|oil spill]] and illustrates practical/methodological aspects of the realization of the survey.
 
The case study on impacts from tourist uses of coastal zones represents results from a study on tourist ports based on [[regional economic accounting methods]], concluding that, considering also the indirect impacts of these activities, they might be less profitable than commonly expected.
 
The case study on [[Salinization adaptation and freshwater supply for agriculture in the Dutch Delta|salinization problems for agriculture in the Dutch delta]] gives insights on [[#Deliberation support tools|problem structuring]] within a participatory decision making process.
 
The case study on the [[Case study risk analysis of marine activities in the Belgian part of the North Sea |risks from maritime activities in the Belgian part of the North Sea]] illustrates the procedure of risk assessment based on the risks resulting from maritime transport for the Belgian coast where potential impacts on the natural environment can result from collisions, groundings, and other incidents either among ships or with fixed marine structures such as platforms or wind turbines.
 
  
==  Development and implementation of ICZM in EU coastal nations: present status, success factors and promising strategies – evidence from the evaluation of ICZM in Europe  ==
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Community composition and ecosystem function may change very little under environmental change when the organisms can acclimate to such change or tolerate it for some time (when the change is only temporary). However, all organisms have bounds to what they can temporarily or permanently tolerate, and when change exceeds some of these limits, the community compostion and ecosystem functioning is likely to change.
As put into evidence by the recent report of the evaluation of [[Integrated Coastal Zone Management (ICZM)]] in Europe <ref> Evaluation of Integrated Coastal Zone Management (ICZM) in Europe – final Report, 2006, http://ec.europa.eu/environment/iczm/pdf/evaluation_iczm_report.pdf</ref>, the integration between aspects of protection of natural resources and different conflicting interests of coastal uses has only partially been achieved. Conflicts between social and economic interests on the one side and [[ecosystems|ecosystem]] goals of conservation and re-naturation of coastal areas on the other still remain substantially unresolved in most national contexts. Frequently, economic interests tend to buy out ecological and social goals, including landscape conservation. In cases where a conciliation between conflicts has been achieved in national strategies, their translation into practical management or planning measures results difficult.  
 
  
Existing management strategies either disregard the aspects of conservation of [[Conservation and restoration of coastal and estuarine habitats|coastal and marine natural areas]] or, if these goals are addressed, fail in addressing relevant economic and social dimensions of coastal areas, and very often goals of economic development succeed in dominating upon aims of nature conservation. The difficulty of developing holistic and integrated approaches is observed as a shortcoming in most of the national strategies analyzed.  
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It is unlikely that communities can be resistant to continuous gradual change, such as global warming. Acclimation and phenotypic plasticity do not suffice to maintain the system as it is. Genetic adaptation could allow community members to track such abiotic environmental change, but it is more likely that the area where the community is functioning will be invaded by species that function well at higher temperatures. The original species will thus have to deal with new competitors and predators, in addition to the changed abiotic factor. To some extent the original community can track the preferred temperature range, by moving spatially to greater depths or to alternative gepgraphic areas. But these new areas are likely to differe in other ecological aspects such as water pressure, light climate and perhaps speeds of water flow etc.
  
With regards to single relevant impacts, some improvements have been achieved in terms of cross-sectoral interests: for instance, tourism-driven interest on high bathing water quality has successfully succeeded in translating an environmental goal of clean water into an economic one, contributing to an improvement of water quality and soliciting investments for wastewater treatment in some countries. Nevertheless tourism sector results to be, in the Mediterranean area and in Portugal, the main driver of uncontrolled and apparently uncontrollable urbanization increasing the [[Pressures, impacts and policy responses in European coastal zones|pressure by socio-economic activities on coastal areas]].
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==Adaptation and the consequences of mortality at different trophic levels==
  
With regards to tools to be used for the implementation of the EU Recommendation related to the integration of aspects of multifunctionality in coastal zone management practice, the report presented by the working group on Indicators <ref> Report on the use of the ICZM indicators from the WG- ID, September 2006; http://eur-lex.europa.eu/LexUriServ/site/en/com/2007/com2007_0308en01.pdf </ref> states that the use of the common assessment framework of indicators is still very fragmentary and that only a few countries and regions have started the data collection on the base of the recommended set of indicators.
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External disturbance interacts with internal mechanisms that shape community structure. To understand how an increased mortality of top-predators will affect the entire food chain, it is essential to understand how processes of mutual adaptation within food chains already give shape to existing patterns such as trophic structure (how biomass in ecosystems is partitioned between trophic levels (such as algae, herbivores, carnivores and top-predators)
  
== Future challenges for integration of multifunctionality in coastal zones ==
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... Abundances at different trophic levels (such as algae, herbivores, carnivores and top-predators) and their responses to increased mortality (as under environmental change) depend critically on different mechanisms of adaptation within food chains and on the importance of density dependence at each of these trophic levels. However, different types of adaptation to living in a food chain context (balancing the need to acquire resources with the need to avoid predation) can often have very similar consequences. For example, micro-evolution or behaviour, species replacement and induced defenses at a middle trophic level may all have similar effects on trophic level abundances in disturbed food chains (Abrams and Vos 2003<ref>Abrams, P.A & Vos, M. 2003. Adaptation, density dependence and the responses of trophic level abundances to mortality. Evolutionary Ecology Research 5:1113-1132.</ref>).
Conflicts in coastal zones, which at present conditions are already difficult to conceal, will only be exacerbated by the consequences of [[climate change]].  Coastal zones along with their activities and services that are provided for society will be interested in the consequences of [[sea level rise]], more frequent storm surges and by general impacts of changes in climate such as heat waves, reduced rainfall with all consequences on water resources etc. The challenge of economic assessments and of policies acting on integration between social, economic and natural resources will lay in the support for decision making for adaptation strategies, confronting social, economic and ecologic advantages of alternative adaptation tools, and putting into relationship economic efforts made in terms of mitigation and adaptation with benefits from reduced vulnerability and increased resilience (further details in the article [[Climate adaptation policies for the coastal zone]]).  
 
  
The discrepancy between a set of tools which facilitate the integration of different sectoral aspects and the still predominantly sector- oriented management practices in European coastal zones represents a challenge to be considered for future action, although the problem will finding a solution not exclusively on a technical level of new or improved tools but first of all in the field of proactive policies.
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==Adaptation assisted by Man==
 
 
A challenge of a different character is represented by the need of adaptation to impacts and the consideration of risks that will be generated by climate change on European coastal zones which is expected to affect generally the opportunities and threats for economic activities in coastal zones. In this context, the evaluation of risks generated by future changes will become an integrated component of future planning activities in coastal zones.
 
 
 
==Conclusions==
 
Although throughout recognized as an important issue, integration of aspects deriving from socio-economic pressures into coastal zone management processes is still at its beginning. Strategies and instruments for facilitating integration exist to some extent, but, although approved at a scientific level, they are scarcely used at a day-to-day practice in coastal zone management. The lack of integration of economic and social factors into management strategies and decision making processes seriously hampers good practice in coastal zone management, as conflicts between uses are shifted to the implementation phase, with the risk of strategies and decisions being altered in an uncontrolled manner.
 
  
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Protecting sources, not sinks when creating Marine Protected Areas. Protecting sources of populations at all stages of succession, to preserve 'ecological memory' to the fullest possible extent. This includes protecting not only 'high quality' habitats that harbour healthy mature communities, but also 'low quality' and disturbed habitats that are required for those species that contribute to early recovery of perturbed areas (see Rossi et al. 2009<ref name ="rossi"/>).
  
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==References==
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<references/>
  
==See for more detailed information on concepts, approaches and tools ==
 
 
:[[Tools for valuation assessments]] – overview of methods.
 
:[[Defining marine biological value]] - different ways of defining the value of biodiversity.
 
:[[Biodiversity as a marine valuation concept]] – valuation of biodiversity including biodiversity structure and ecosystem functioning.
 
:[[Total Economic Value]] - TEV is composed by use values, option values and non-use components.
 
:[[Economic Value]] - defining a price for the environment.
 
:[[Hedonic Evaluation Approach]] - value connected to present and, with some caution, future uses.
 
:[[Non-use value: bequest value and existence value]] - a value associated that does not concern our use, either direct or indirect, of the environment, its resources or services.
 
:[[Values of amenities in coastal zones]] – value of landscapes to those who benefit.
 
:[[Contingent Valuation Method]] - economic, non-market based valuation method especially used to infer individual’s preferences for public goods, notably environmental quality.
 
:[[Travel cost method]] – method for estimating the use values of recreational sites.
 
:[[Value Transfer]] – use values obtained from one site for other sites with close characteristics.
 
:[[Socio-economic evaluation]] – overview of different methods to assess socio-economic impacts.
 
:[[Regional economic accounting methods]] – assessment of the direct and indirect socioeconomic impact of changes in the environment on the regional economy.
 
:[[Evaluate non market value of fishing activities]] – willingness to pay for attributes such as the presence of a fishing harbour.
 
:[[Green accounting]] - Directly Expanded National Accounts = national accounts expanded with environmental information in physical or monetary units, or both.
 
:[[Computable general equilibrium]] - class of economic models that use actual economic data to estimate how an economy might react to changes in policy, technology or other external factors.
 
:[[Input-output matrix]] - representation of national or regional economic accounting that records the ways industries trade with one another as well as produce for consumption and investments.
 
:[[Integrated Assessment]] - interdisciplinary approach to assessment based on combining, interpreting and communicating knowledge from diverse scientific disciplines.
 
:[[Multicriteria techniques]] - integrate into the decision process quantified economic aspects as well as non-economic aspects that cannot be quantified in monetary terms.
 
:[[Supply chain analysis]] - the complete sequence of operations and added value from the raw material to intermediate products to final consumer products.
 
:[[Carrying capacity analysis]] - the growth limits an area can accommodate without violating environmental capacity goals.
 
 
 
== References ==
 
<references/>
 
  
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<br>
  
 
{{author
 
{{author
|AuthorID=12523
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|AuthorID=11928
|AuthorName=Margaretha
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|AuthorFullName=Vos, Matthijs
|AuthorFullName=Margaretha Breil}}
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|AuthorName=Matthijs}}
  
[[Category:Integrated coastal zone management]]
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[[Category:Coastal and marine ecosystems]]
[[Category:Principles and concepts in integrated coastal zone management]]
 
[[Category:Evaluation and assessment in coastal management]]
 

Latest revision as of 10:45, 2 May 2020

Resilience and resistance


Definition of Resistance:
The capacity to weather a disturbance without loss [1].
This is the common definition for Resistance, other definitions can be discussed in the article
Definition of Resilience:
The capacity to recover from a disturbance after incurring losses [1].
This is the common definition for Resilience, other definitions can be discussed in the article


Introduction

Coastal and marine ecosystems are affected by environmental disturbance at a variety of spatio-temporal scales. The organisms inhabiting these systems are adapted to such disturbance, either by being tolerant of these conditions or by playing a role in one or more of the successional stages that follow during ecosystem recovery.

Uses1.jpg

If all species in the system were tolerant to a particular perturbation, very little would change at the ecosystem level, and we could call the system resistant to this disturbance. However, often a disturbance, such as a temporary very low oxygen level, affects a substantial proportion of the organisms dramatically, either causing them to die, or forcing them to rapidly migrate to more favorable parts of the environment. Such a catastrophic disturbance could locally defaunate a certain volume in the pelagic or a certain area of hard or soft substrate. Such destruction at a local scale does not mean the end of local functioning; Usually organisms are available at a larger spatial scale that can re-colonize the affected area, according to their particular tolerances and abilities to favorably affect their local environment. The term resilience has been used in different ways, first of all for the rate of recovery to the previous state and secondly for the system's ability to re-organize itself. Both resistance and resilience cause an ecosystem to remain relatively unchanged when confronted by a disturbance, but in the case of resistance no internal re-organization and successional change is needed. In contrast, resilience implies that the system is internally re-organizing, perhaps through a mozaic of patches that are at different stages of re-assembly. When considering the potential effect of a certain type of disturbance it is thus useful to ask two questions: (1) Will the species of this system be able to tolerate it (implying resistance), and if not, (2) Is recovery possible through a successional trajectory, back to the same, or at least a desirable, ecosystem state (implying resilience)? It should be clear that the system will not be sufficiently resistant when (even gradual) uni-directional change acts faster than the organisms' ability to adapt their tolerances. If uni-directional gradual change is this fast, the system will not be sufficiently resilient either, as full recovery through succession will then not be possible. Recovery from sudden and local disturbance is usually possible through re-colonization, but the rate of recovery will depend tremendously on the spatial extent of disturbance. For example, recovery from anoxia could take 5 to 8 months at the scale of square meters (Rossi et al. 2009[2]), but could take 5 to 8 years at the scale of a whole bay(Diaz & Rosenberg 1995[3]).


while resilience has been defined in different ways: it can be a measure for the speed at which an ecosystem returns to its former state following a (minor) disturbance. The idea is that a system with a short return time is more resilient than one with a long return time. Such resilience measured as (1 / the return time to a stable equilibrium) has also been called engineering resilience. It has however a long history of use among ecologists (Pimm 1982[4], DeAngelis 1992[5], Vos et al. 2005[6]). It is also used in a way that more closely resembles the definition of resistance. Ecological resilience ... (cite Gunderson 2000[7] to avoid confusion)


Coastal systems are naturally resilient. ... This article will discuss. In particular it will argue that ...

Biodiversity allows ecosystems to adapt to changing conditions. Humans, however, have acted to increase the rate of change and consequently, it will be a great challenge for the marine environment to adapt rapidly enough in the future. These changes have been induced through pollution, fishing, sediment deposition and alteration of the global climate. Without genetic diversity, natural selection cannot occur and natural selection is limited, then adaptation is impossible. It is evident that the preservation of biodiversity and, more specifically, genetic diversity is of paramount importance for successful adaptation to our rapidly changing environments.

Biodiversity may not act as a protect ecosystems from major abiotic disturbances

for Biodiversity: cite: Folke et al. 2004[8]

Resilience through re-colonization

To understand resilience of ecosystems it is essential to understand what drives succession within these ecosystems. Succession determines how, and how fast, communities return back to their original state, or perhaps enter a new state. many aspects of succession can be understood in terms of trade-offs between the ability to be either a good early (re-)colonizer, or a good competitor (r-species versus a K-species). Succession involves a gradual replacement of species that differ in these traits and that differ in the degree they tolerate, facilitate or inhibit certain environmental conditions and other species. ... see (Rossi et al. 2009[9])

We could thus also call a system resilient when it is organized in such a way that succession leads to a recovery of the original state.

Resilience and nutrient inputs

DeAngelis et al. 1989[10] showed in their analysis of a food chain model that resilience, measured as (1/return time), increased smoothly with nutrient enrichment. The idea is that the system can more quickly return to its original state when the nutrient input is high. However, this result depends on the exact shape of the functional response, the way predators consume their prey as a function of prey density. DeAngelis et al. had used a highly stabilizing Type III (a sigmoid-shaped) functional response. Such a functional response is realistic for learning predators and those that switch between different prey types. Vos et al. 2005[11] found that resilience (1/return time) would first increase, but then decrease again under nutrient enrichment, when a Type II functional response was used in the model. Many species of consumers throughout the animal kingdom consumer their resources with such a functional response, where intake rate first increases, and then gradually levels off with resource density. Food chains with such consumers would be much less resilient under a high pressure of nutrient enrichment.


Resistance to changes in abiotic and biotic factors

Community composition and ecosystem function may change very little under environmental change when the organisms can acclimate to such change or tolerate it for some time (when the change is only temporary). However, all organisms have bounds to what they can temporarily or permanently tolerate, and when change exceeds some of these limits, the community compostion and ecosystem functioning is likely to change.

It is unlikely that communities can be resistant to continuous gradual change, such as global warming. Acclimation and phenotypic plasticity do not suffice to maintain the system as it is. Genetic adaptation could allow community members to track such abiotic environmental change, but it is more likely that the area where the community is functioning will be invaded by species that function well at higher temperatures. The original species will thus have to deal with new competitors and predators, in addition to the changed abiotic factor. To some extent the original community can track the preferred temperature range, by moving spatially to greater depths or to alternative gepgraphic areas. But these new areas are likely to differe in other ecological aspects such as water pressure, light climate and perhaps speeds of water flow etc.

Adaptation and the consequences of mortality at different trophic levels

External disturbance interacts with internal mechanisms that shape community structure. To understand how an increased mortality of top-predators will affect the entire food chain, it is essential to understand how processes of mutual adaptation within food chains already give shape to existing patterns such as trophic structure (how biomass in ecosystems is partitioned between trophic levels (such as algae, herbivores, carnivores and top-predators)

... Abundances at different trophic levels (such as algae, herbivores, carnivores and top-predators) and their responses to increased mortality (as under environmental change) depend critically on different mechanisms of adaptation within food chains and on the importance of density dependence at each of these trophic levels. However, different types of adaptation to living in a food chain context (balancing the need to acquire resources with the need to avoid predation) can often have very similar consequences. For example, micro-evolution or behaviour, species replacement and induced defenses at a middle trophic level may all have similar effects on trophic level abundances in disturbed food chains (Abrams and Vos 2003[12]).

Adaptation assisted by Man

Protecting sources, not sinks when creating Marine Protected Areas. Protecting sources of populations at all stages of succession, to preserve 'ecological memory' to the fullest possible extent. This includes protecting not only 'high quality' habitats that harbour healthy mature communities, but also 'low quality' and disturbed habitats that are required for those species that contribute to early recovery of perturbed areas (see Rossi et al. 2009[9]).

References

  1. 1.0 1.1 Lake, P.S. 2013. Resistance, Resilience and Restoration. Ecological Management and Restoration 14: 20-24
  2. Rossi, F., Vos, M. & Middelburg, J.J. Species identity, diversity and microbial carbon flow in reassembling macrobenthic communities. Oikos 118:503-512.
  3. Diaz, R.J. & Rosenberg, R. 1995. Marine benthic hypoxia: a review of its ecological effects and the behavioural responses of benthic macrofauna. Oceanogr. Mar. Biol. Annu. Rev. 33:245-303.
  4. Pimm, S.L. 1982. Food Webs. The University of Chicago Press.
  5. DeAngelis, D.L. 1992. Dynamics of Nutrient Cycling and Food Webs. Chapman and Hall, London.
  6. Vos, M., Kooi, B.W., DeAngelis, D.L. & Mooij, W.M. Inducible defenses in food webs. In: Dynamic Food Webs. Multispecies Assemblages, Ecosystem Development and Environmental Change. Eds. P.C. de Ruiter, V. Wolters & J.C. Moore. Academic Press. Pp. 114-127.
  7. Gunderson, L.H. 2000. Ecological Resilience - in Theory and Application. Annual Review of Ecolog and Systematics 31:425-439.
  8. Folke, C., Carpenter, S., Walker, B., Scheffer, M., Elmqvist, T., Gunderson, L. & Holling, C.S. 2004. Regime Shifts, Resilience, and Biodiversity in Ecosystem Management. Annual Review of Ecolog and Systematics 35:557-581.
  9. 9.0 9.1 ).Rossi, F., Vos, M. & Middelburg, J.J. 2009. Species identity, diversity and microbial carbon flow in reassembling macrobenthic communities. Oikos, Early View, (January issue).
  10. DeAngelis, D.L., Bartell, S.M. & Brenkert, A.L. 1989. Effects of nutrient recycling and food chain length on resilience. American Naturalist 134: 778-805.
  11. Vos, M., Kooi, B.W., DeAngelis, D.L. & Mooij, W.M. 2005. Inducible defenses in food webs. In: Dynamic Food Webs. Multispecies Assemblages, Ecosystem Development and Environmental Change. Eds. P.C. de Ruiter, V. Wolters & J.C. Moore. Academic Press. Pp. 114-127.
  12. Abrams, P.A & Vos, M. 2003. Adaptation, density dependence and the responses of trophic level abundances to mortality. Evolutionary Ecology Research 5:1113-1132.



The main author of this article is Vos, Matthijs
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Citation: Vos, Matthijs (2020): Testpage3. Available from http://www.coastalwiki.org/wiki/Testpage3 [accessed on 2-07-2020]