陕北煤炭开采地区河道生态基流的计算与盈亏分析

陕北地区水资源非常短缺,特别是煤炭开采地区。以窟野河流域为例,首先采用基流比例法、Tenent法和最小月平均流量法分别计算了温家川站的生态基流;其次通过对比分析各种计算结果得出基流推荐值,分析了生态基流的盈缺状况,并探讨了造成生态基流缺失的主要因素。结果表明,窟野河温家川站的年生态基流推荐值为3.50 m~3/s,年内丰水期、平水期、枯水期的推荐值分别为6.00 m~3/s、3.50 m~3/s、2.50 m~3/s。1999年之前生态基流还有很大的盈余,但近些年流量明显减少,4、5、6月平均流量都不能满足生态基流,其中煤炭开采是主要因素之一。

Calculation and profit-loss analysis for the ecological basic flow in the northern Shaanxi coal mining area

This paper takes Kuye River as a sample case study to analyze its profit and loss battle by using the basic flow rate method (BFR) proposed by the author.For the study purpose,we have first of all studied the ecological basic water current of a river named Wenjiachuan for the different years and seasons to find out its different flowing water volume by using the tenent method and the minimum monthly average flow method (MAF).As is well known,the northern part of Shaanxi,especially in the coal mining areas,is extremely poor in water resources,which makes it of great significance to carefully protect and analyze its profitloss situation to save the region's basic ecological water resources.And,finally,through the analysis of calculation results worked out by using various methods,we have brought forward our recommendation and ecological basic flow investigation results of the river.The results of our calculation of the river water volume reveal that:the basic ecological basic flowing volume of the river offered by the BFR method is equal to 1.42-11.14 m3/s,whereas that gained with the tenant method is equal to 1.94-8.50 m3/s.On the other hand,it has been detected to be 2.95-10.87 m3/s by using the MAF method.Furthermore,in accordance with the comparison and analysis results of the Kuye River's ecological basic flow,the recommended value accounts for 3.50 m3/s,while the calculation results of the water flow volume in the wet season (July-Oct),and that of the average season (Mar-Jun) and the dry season (Nov-Feb) are roughly equal to 6.00 m3/s,3.50 m3/s,2.50 m3/s,respectively.However,a large surplus had been found before 1999,but from 1999 to 2010,the water-flow volume of the on-spot evaluation and examination has been proved very close with that of the ecological basic flow.For example,the average flow volume from Apr to Jun tends to be smaller than that of the ecological basic flow.The main influential factors that make the river's ecological basic flow profit and loss are the rainfall,temperature,water and soil conservation,the coal mining water consumption,and so on.Nevertheless,from 1999 on,coal mining has turned up to be the dominant influential factor in creating the water-shortage ecological effect.Thus,it can be seen that the result of our investigation can be expected to offer a meaningful technical support for the need of ecological restoration of the river basin.