宁夏党家岔湿地自然保护区堰塞湖群的水质现状

Present Status of Water Quality of the Barrier Lakes in Dangjiacha Wetland Nature Reserve,Ningxia

于2016年8月31-9月1日和2017年8月8-9日,在宁夏党家岔湿地自然保护区的党家岔堰、苏堡堰、堡玉堰、河滩堰中,采集水样,选取p H、溶解氧含量、化学需氧量含量、五日生化需氧量、氨氮含量、总氮含量、总磷含量、高锰酸盐指数、氟化物含量、六价铬Cr（Ⅵ）、总溶解固体含量等评价指标,对堰塞湖水质现状进行了综合分析。结果表明,堰塞湖水体符合Ⅴ类水域标准,属重度污染,其主要污染物为化学需氧量、总氮和总磷等;主成分分析结果显示,化学需氧量含量、总磷含量、总氮含量、p H、五日生化需氧量和高锰酸盐指数是决定堰塞湖水质的关键因子;各堰塞湖水体p H差异显著（n=137,p〈0.05）,苏堡堰水体p H最小,为8.23-8.83,党家岔堰和堡玉堰水体p H分别为8.45-8.90和8.86-9.89,河滩堰水体p H最大,为9.22-9.97;各堰塞湖水体总氮含量差异显著（n=137,p〈0.05）,党家岔堰、苏堡堰、堡玉堰和河滩堰水中的总氮质量浓度依次为1.274-3.684 mg/L、2.006-3.567 mg/L、3.214-4.838 mg/L和7.681-9.983 mg/L;苏堡堰水中的总碳、无机碳和总有机碳含量都最大,其次为党家岔堰和堡玉堰的,河滩堰的最小。

From August 31 to September 1, 2016, and from August 8 to August 9, 2017, the water samples were sampled from the Barrier Lakes in the Dangjiacha Wetland Nature Reserve, Ningxia. The sampled lakes included the Dangjiacha Lake, Subu Lake, Buyu Lake, and Hetan Lake. The p H, dissolved oxygen content,chemical oxygen demand content, 5 th Biochemical oxygen demand content, ammonia nitrogen content, total nitrogen content, total phosphorus content, permanganate index, fluoride content and Cr（VI） were selected as evaluation indicators to comprehensively analyze the water quality status of the barrier lakes. The results showed that waters of the barrier lakes are Grade V, which were heavily polluted, and the main pollutants were chemical oxygen demand, total nitrogen and total phosphorus. The chemical oxygen demand content, total phosphorus content, total nitrogen content, p H, 5-day biochemical oxygen demand content and permanganate index were the key factors affecting the water quality of the barrier lakes. The p H of each lake was significantly different（n=137, p0.05）. Among them, p H of the Subu Lake was the lowest（8.23-8.83）, followed by the Dangjiacha Lake（8.45-8.90） and the Buyu Lake（8.86-9.89）. The p H of the Hetan Lake was the highest,ranging from 9.22-9.97. Total nitrogen contents in the various barrier lakes were significantly different（n=137, p0.05）. The total nitrogen concentrations in the Dangjiacha Lake, Subu Lake, Buyu Lake, and Hetan Lake were 1.274-3.684 mg/L, 2.006-3.567 mg/L, 3.214-4.838 mg/L and 7.681-9.983 mg/L. The total carbon,inorganic carbon and total organic carbon content were the largest in Subu Lake, followed by Dangjiacha Lake and Buyu Lake, and the Hetan Lake was the smallest.