Information-based Network Environ Analysis for Ecological Risk Assessment of heavy metals in soils

An information-based Network Environ Analysis (NEA) model coupled with fuzzy sets theory is developed and applied to a Thermal Power Plant (TPP) Ecological Risk Assessment (ERA) problem in this paper. Multiple sets of initial risk values are got by calculating different fuzzy evaluation grades of probability and then the advanced NEA model is applied to integrate the ecological risk of operation for the complex ERA of this soil ecosystem. The evaluation results show that the integral risk to soil microorganism can reach 1.6 times greater than the initial risk, while herbivores and carnivores (no initial risks) have to suffer 1/9 to 1/6 of vegetation's initial risks from external environment, and different probability distributions lead to multiple ERA results. This study quantified the multi-grade risks to entire system components and identified complex internal risk flow paths. The model is applied to multiple receptors with mutual ecosystem interference comparing to the existing one-fold risk evaluation and proved to be more comprehensive for ERA research in soils. (C) 2016 Elsevier B.V. All rights reserved.