CENTRAL ISSUES FOR AQUATIC FOOD WEBS: FROM CHEMICAL CUES TO WHOLE SYSTEM RESPONSES
Additional Document Info
Aquatic ecosystems worldwide provide important resources for human populations. Estuarine and marine habitats provide many essential ecosystem services, including climate regulation, yet currently these systems are impacted over large areas through over-exploitation and degradation. Moreover, aquatic ecosystems represent an integrative picture of environmental impacts and management practices operating in the terrestrial hinterland. Scientists have as yet not been able to develop predictive whole ecosystem simulation models, and no single method of food web analysis has been subjected to extensive validation of its predictive capabilities. This chapter describes factors that act at the level of individuals and populations, but whose influence on the food web dynamics and ecosystem functioning is as yet poorly understood. It is suggested that the neglect of these factors, among others to be discovered and explored, contributes to the uncertainty of predictive ecosystem simulation models. The use of larger-scale network approaches and the need for quantitative descriptors of food webs is emphasized, and concluded with challenges in application of food web theory to management issues in aquatic systems. 2006 Elsevier Inc. All rights reserved.