NETWORK ENVIRON ANALYSIS: A MATHEMATICAL BASIS FOR DESCRIBING INDIRECT EFFECTS IN ECOSYSTEMS

Abstract

A mathematical basis for describing and analyzing holistic properties of ecosystems based on a fundamental theory of systems ecology, environ theory, is presented. The analytical methodology, network environ analysis (NEA), is introduced as a quantitative approach for ecological network analysis using a conceptual five-compartment steady-state model simulating the flow of a conserved tracer in an ecosystem. Throughflow, total system throughflow, and environ flow are presented as properties for analysis of ecosystems as networks. Quantitative information is generated for ten intercompartmental relationships within the network model for which no information is available from the simulated data. Results indicate that these ten relationships are indirect and account for 41.8% of total system throughflow in the network. In addition, the fate of system-level inputs in terms of environ flows and boundary exchanges give mathematical description of properties and relationships that are not observable based on the simulated data alone. It is proposed that a quantitative description of non-observable, indirect relationships should be developed in order for ecosystems to be designed and managed as interconnected, holistic systems, and that NEA offers promise in that direction.