Construct for Analysis of Ecosystem Perturbations Based on Input/Output Analysis

摘要

One primary concern of ecological assessment is to determine how the integrity of an ecosystem as a whole has been affected by perturbation. A construct is developed here, based on the material flow characteristics of systems, that is an alternative or complement to the traditional methods of inventory and simulation. Leontief input/output analysis is adapted to the assessment of material budgets (including intrasystem flows). The theory and principles of the methodology are developed and then a preliminary feasibility study is conducted by testing the construct on case histories of Lake Washington and Findley Lake. Cases tested included monthly, seasonal, and annual analyses of Lake Washington carbon data at two levels of aggregation; seasonal and annual analyses of carbon, phosphorus, and nitrogen data for two years for Findley Lake; and a four-lake comparison of the use of dissolved inorganic carbon (DIC) as an endogenous or exogenous term in carbon budgets. Emphasis was placed on the problems of time, compartment, and material aggregation, on the problems of construct sensitivity to tracing changes, and on the development of an overall system index. (ERA citation 08:016104)