Unravelling river impairments with an integrated risk approach
1. Rivers are complex systems for which it is hard to make reliable assessments of causes and responses to impairments. In absence of a complete understanding of the causal relationships, risk approaches facilitate the integration of all possibly intervening factors in the assessment. 2. Application of risk approaches can help in establishing comprehensive assessments when entered in a holistic framework of a scale-hierarchic aggregation and integration of information and inference of relationships. Both in the construction of indicators for magnitude of stressors and in the inference of ecosystem processes and structures, risk-based approaches can be useful. Yet, we have to go further than simply replacing uncertainty by a risk factor. The transcription of uncertainty to causal relationships in probability distributions for both magnitude of impairment and weight of different descriptors, with an associated confidence in diagnostic is a more accurate and rigorous way to introduce the notion of risk. 3. We present a comprehensive framework for the river ecosystem with integrated risk approaches to elucidate relationships and influences to complex ecosystem processes and structures, which offers an appealing tool to facilitate diagnosis of the likely causes of impairment and predict future conditions. Appropriate statistical modelling approaches like Bayesian Belief Networks and Bayesian hierarchic inference allow dealing with these risks to predict impairments and potential recovery of river ecosystems. The ability of risk approaches to integrate multi-scale quantitative and qualitative descriptors in the identification of multiple stressor sources and pathways and their impairment of specific processes and structures is illustrated for sub-models of hydromorphology. 4. The risk-based framework not only dresses a more complete picture of ecosystem impairments, it also offers a comprehensive, user-friendly tool to instruct the decision process.
ecological assessment ecosystem functions Bayesian Belief Networks hydromorphology ecological risk analysis
K.Van Looy J.Piffady T.Tormos Y.Souchon
Irstea, MALY, river hydro-ecology unit, Lyon, France Irstea, MALY, river hydro-ecology unit, Lyon, France;Onema, river hydro-ecology unit Onema-Irstea, L
国际会议
The 3rd Biennial ISRS Symposium Achieving Healthy and Viable Rivers (ISRS)第3届国际河流大会
北京
英文
2-12
2013-08-05（万方平台首次上网日期，不代表论文的发表时间）