An Inexact Two-Stage Water Quality Management Model for Supporting Sustainable Development in a Rural System

Abstract

Water quality management is essential for preserving valuable water resources and facilitating sustainable socio-economic development in watershed systems. However, it is challenging for decision makers to identify desired schemes for management of economic development and environmental protection due to complexities of rural systems. In this study, an inexact two-stage water quality management (ITWQM) model is developed for supporting economic and environmental management of a rural area in Heshui Watershed. In the modeling formulation, pollutant discharge and soil loss are allowed under a range of relaxed constraints in association with a variety of probabilities, such that the reliability of satisfying (or risk of violating) system constraints can be analyzed; besides, penalties are imposed when policies expressed as allowable pollutant discharge levels are not satisfied. Solutions in connection with regional sustainable development such as land use, water quality protection, crop cultivation, livestock husbandry, forest expansion, fishery and industrial production, have been obtained. The results can be used for generating decision alternatives and helping local managers to identify desired policies under various environmental, economic, and system-reliability conditions. Decisions at a lower risk level would lead to an increased reliability in fulfilling environmental requirements but with a reduced system benefit; conversely, a desire for increasing system benefit could result in a raised risk of violating environmental constraints.

Keywords: optimization, risk analysis, sustainable development, water quality, uncertainty