Model And Method Of Water Waste Loads Allocation In A Region

It is the core of water pollutant total amount control to allocate water waste loads. In this research, three models for water waste loads allocation were proposed based on different combinations of decision making principles such as equity, efficiency, and regional differences which should be followed in waste loads allocation. As a case, these models were applied to the distribution of reduction amount of COD and NH3-N loads among nine cities and counties in Chaohu Lake Basin. The main results were summarized as follows:(1) In terms of the characteristic of Gini coefficient reflecting the unfair level in economics, six indices were selected from such fields as society, economy, environment, etc., to construct an assessment system for water waste loads, which was measured for equity by using environmental Gini coefficient. Considering the fuzziness and imprecision of statistical data and differences in the importance of assessment indices, a fuzzy optimization model, with elastic constraints and weighted information entropy, was proposed for waste loads allocation, and solved by the fuzzy linear programming.(2) On the basis of defining weighted comprehensive Gini coefficient and environmental economic benefit parameter, a multi-objective decision making model for waste load allocations, which takes such three factors as economic income maximum, pollution abatement cost minimum and weighted comprehensive Gini coefficient minimum to be objectives, was proposed from the viewpoints of economy optimization and fair principles, and solved by the ideal point method.(3) Based on the principles of equity and efficiency and the differences between subdistricts, an evaluation index system for water waste loads allocation was established, which contained a multi-level structure comprised of sixteen indices involved in society, economic, environment, technique and management etc. According to the characteristics that attached and non-attached information are both taken into consideration by Vague set theory, a multi-objective decision making model was proposed for water waste loads allocation.(4) Take the 2007 year as the base year of water waste loads allocation, the reduction amount of water waste loads are distributed in Chaohu Lake basin, under the target of the total amount control in the "Eleventh Five-Year Plan". Study results indicated that Hefei City got the largest reduction amount of COD and NH3-N loads, and Lujiang County and He County were focused on reducing regions in seven counties of the basin. Although there were some differences among the results from different allocation methods, it proved the science and rationality of the allocation methods by fiting with the local social and economic situations.