Non-equilibrium theory of ecosystem function: from phase dynamics to coastal ecosystems

点击翻译按钮获取中文摘要

The goal of the proposed research is to develop and test a non-equilibrium theory of large-scale ecosystems with explicit consideration of spatial flows of individuals and matter. Our understanding of natural ecosystems has progressed from the study of local ecological interactions to theories integrating spatial movement and interactions of individuals across scales. However, well-documented flows of organic and inorganic matter in coastal waters, are still not well integrated into predictions of regional population persistence and biodiversity. The research will first develop a general non-equilibrium theory of meta-ecosystems. We will adopt a coupled-oscillator approach to approximate and simplify the model as phase dynamics that can describe relationships between many non-equilibrium coupled systems. This formalism will allow the prediction of regional ecosystem functions and of spatiotemporal heterogeneity as spatial asynchrony through the interaction between fluxes of individuals and matter. We will use intertidal mussel beds as a model system and conduct mesocosm experiments with metabolic chambers to test the role of simple competitive and trophic interactions among mussels and with dominant associated species for fluxes driving ecosystem functions (e.g. oxygen, ammonium, chlorophyll a). The goal of these experiments will be to test for feedbacks between population-level connectivity and ecosystem functions. Experimental results will be integrated into a specific theory of coastal meta-ecosystems, and we will predict spatial synchrony between fluctuations of organic and inorganic matter. We will validate our predictions by conducting a large-scale (150km) field survey along the south shore of the St. Lawrence Estuary and from existing (e.g. CHONe, LTER, PISCO) datasets. These theories and results will provide a more general theory of ecosystem-based management and of marine reserve networks where size and spacing of reserves are optimized for interconnections among populations and matter over regional scales that are relevant to policy makers and managers. They will also position trained students at the leading edge of ecosystem-based marine science and conservation.