喀什河流域重要渔业水域环境质量评估OA

In order to assess the environmental quality of important fishery waters in the Kashi River Basin,the wa-ter quality of Kashi River,one of the three tributaries of the Ili River,was investigated from April to November 2023.The pH value,suspended matter,chlorophyll a(Chla),nitrite nitrogen(NO2--N),nitrate nitrogen(NO3--N),ammonia nitrogen(NH4+-N),permanganate index(CODMn)were determined),total nitrogen(TN),total phosphorus(TP),dissolved oxygen(DO),water temperature T,dissolved phosphate(PO43-),sul-fide(S2-)a total of 13 indicators.The water quality and pollution characteristics of the basin were studied,and the nutritional status was evaluated by comprehensive nutritional status index.The results show that the water quali-ty of Kashi River basin is weakly alkaline,the average pH value is 7.24～8.64,and the DO varies greatly throughout the year,ranging from 4.18 mg/L to 12.39 mg/L.There was no significant difference in CODMn content among all sampling points(P＞0.05),and the variation range was 0.6 mg/L～2.1 mg/L.TN content in nutrient salts had significant differences at different time and sampling points(P＜0.05),TN content in culture area in-creased compared with control area,and TN content gradually decreased after leaving culture area.The content of chlorophyll a(Chla)in cage culture area was slightly higher than that in control area.The comprehensive nutrition index of each sampling point was 15.71～22.87,and the water body was in the state of poor nutrition.The evalua-tion results can provide data accumulation and technical support for the development and utilization of fishery re-sources in Xinjiang's suitable fishing waters.