围网养殖对洪湖水质的影响分析

文章从围网养殖对洪湖水质影响的角度出发,依据1990～2006年在洪湖实测的水质数据分析了洪湖水质的时空变化过程及趋势,并发现水质指标中总氮的超标量变化明显。利用环境污染综合指数法,通过围网内和围网外以及围网前和围网后不同水文期的水质情况对比,对洪湖水质变化进行综合评价。结果表明围网内的环境污染综合指数在枯水期要远大于围网外的,围网养殖对湖泊的局部污染严重;围网前水质基本可以达到Ⅱ类水质标准,开始围网后洪湖水质逐步恶化,且围网养殖面积与水质恶化的程度有着相同的变化趋势,总氮的含量变化尤为明显,随着围网养殖规模面积的扩大急速增加。

Analysis of Influence of Enclosure Aquaculture on Water Quality of Honghu Lake

Influence of enclosure aquaculture on the water quality of Honghu Lake,Hubei Province was discussed. Change and trend process of water quality based on the measured data of the Lake from 1990 to 2006 were analyzed,and it was found that total nitrogen was out of limits markedly. Water quality was assessed through environmental contamination index method and compared in the enclosure positions with out of enclosure in different hydro-periods,as well as before the enclosure aquaculture with the after. Results showed that environmental contamination index in the enclosure positions was much larger than the outside in dry season. Enclosure aquaculture has polluted part of the Lake severely. Before the enclosure aquaculture,water quality conformed to Grade II in water classification,while after the enclosure,water quality in the Lake gradually deteriorated. There were some relationships between the area of enclosure aquaculture and degree of water quality deterioration. Content of total nitrogen changed obviously,which may increase sharply with increasing area of enclosure aquaculture.