Chen Ding-jiang, Lü Jun, Shen Ye-na, Jin Shu-quan, Shi Yi-ming
Department of Natural Resources, College of Environmental Science and Resources, Zhejiang University, Hangzhou 310029, China.
Huan Jing Ke Xue. 2008 Sep;29(9):2437-40.
Based on the one-dimension model for water environmental capacity (WEC) in river, a new model for the WEC estimation in river-reservoir system was developed in drinking water source conservation area (DWSCA). In the new model, the concept was introduced that the water quality target of the rivers in DWSCA was determined by the water quality demand of reservoir for drinking water source. It implied that the WEC of the reservoir could be used as the water quality control target at the reach-end of the upstream rivers in DWSCA so that the problems for WEC estimation might be avoided that the differences of the standards for a water quality control target between in river and in reservoir, such as the criterions differences for total phosphorus (TP)/total nitrogen (TN) between in reservoir and in river according to the National Surface Water Quality Standard of China (GB 3838-2002), and the difference of designed hydrology conditions for WEC estimation between in reservoir and in river. The new model described the quantitative relationship between the WEC of drinking water source and of the river, and it factually expressed the continuity and interplay of these low water areas. As a case study, WEC for the rivers in DWSCA of Laohutan reservoir located in southeast China was estimated using the new model. Results indicated that the WEC for TN and TP was 65.05 t x a(-1) and 5.05 t x a(-1) in the rivers of the DWSCA, respectively. According to the WEC of Laohutan reservoir and current TN and TP quantity that entered into the rivers, about 33.86 t x a(-1) of current TN quantity should be reduced in the DWSCA, while there was 2.23 t x a(-1) of residual WEC of TP in the rivers. The modeling method was also widely applicable for the continuous water bodies with different water quality targets, especially for the situation of higher water quality control target in downstream water body than that in upstream.
基于河流一维水环境容量模型，开发了一种适用于饮用水水源保护区河库系统水环境容量估算的新模型。在新模型中，引入了饮用水水源保护区内河流的水质目标由水库饮用水水源水质需求决定的概念。这意味着水库的水环境容量可作为饮用水水源保护区上游河段末端的水质控制目标，从而避免水环境容量估算中存在的问题，如河流与水库水质控制目标标准的差异，例如根据中国国家地表水环境质量标准（GB 3838 - 2002），水库与河流中总磷（TP）/总氮（TN）的标准差异，以及水库与河流中水环境容量估算设计水文条件的差异。新模型描述了饮用水水源与河流的水环境容量之间的定量关系，实际上表达了这些低水区域的连续性和相互作用。作为案例研究，运用新模型对位于中国东南部的老虎潭水库饮用水水源保护区内河流的水环境容量进行了估算。结果表明，饮用水水源保护区内河流中总氮和总磷的水环境容量分别为65.05 t·a⁻¹和5.05 t·a⁻¹。根据老虎潭水库的水环境容量以及当前进入河流的总氮和总磷量，饮用水水源保护区内需削减约33.86 t·a⁻¹的当前总氮量，而河流中总磷仍有2.23 t·a⁻¹的剩余水环境容量。该建模方法也广泛适用于具有不同水质目标的连续水体，特别是下游水体水质控制目标高于上游的情况。
