青海湖2015年水质参数特征及其变化 Characteristics and Changes of Water Quality Parameters of Qinghai Lake in 2015

通过对2015年9月22~24日在青海湖进行水温、溶解氧、pH、叶绿素a浓度、浊度垂直剖面监测，同时采集湖水样通过实验测定湖水总磷、总氮含量，采集各入湖河流进行营养盐测定，结合青海湖管理局提供的数据进行对比，分析了青海湖水体理化状况及湖水营养状况。结果显示，各监测区域水体理化参数、营养化程度存在一定差异，受风力及湖流扰动影响，湖心处存在较弱的分层现象；湖心处溶解氧浓度较低，受温度分层影响出现溶解氧分层现象；青海湖高盐度、高离子浓度是控制其pH并对溶解氧浓度及浊度等产生较大影响的主要因素，温度及湖泊水循环引起的底泥释放使得浮游植物多集中在中下层水体，沉水植物具有较好的生长条件。青海湖水体营养水平不高，但总磷浓度在局部有不断增加的趋势，外源输入是影响湖泊营养化程度的主要原因。人类活动的加剧，使青海湖水质存在恶化的风险。 The water temperature, dissolved oxygen, pH, chlorophyll-a concentration and turbidity vertical profile monitoring were carried out at Qinghai Lake during September 22-24, 2015. At the same time, physical and chemical status of Qinghai Lake and lake nutrition status were analyzed by the experimental determination of total phosphorus and total nitrogen content, and nutrient salt determination through collecting water samples, compared with the data from Qinghai Lake Management Bureau. The results showed that there were some differences in physical and chemical parameters and nutritional degree of each point, and due to wind and lake disturbance, there is a weak stratification phenomenon at the center of the lake; the dissolved oxygen concentration at the center of lake is lower, and the dissolved oxygen stratification is affected by the temperature stratification; Qinghai Lake’s high salinity and high hydronium concentration control its pH and have a greater impact on the dissolved oxygen concentration and turbidity. The release of sediment caused by temperature and lake water circulation makes phytoplankton concentrate in the middle and low water, so that submerged plants have better growth conditions. The nutrient level of Qinghai Lake is not high, but the concentration of total phosphorus has a tendency to increase. Exogenous input is the main reason that affects the degree of lake nutrition. The intensification of human activities makes the Qinghai Lake have the danger of deterioration of water quality.