五大连池水质现状及近30年前后变化

Status of water quality and succession changes in Lake Wudalianchi in the last 30 years

2012—2013年春、夏、秋季,对五大连池11个采样点的水质变化进行研究,分析湖水水质现状,比较30年前后湖泊的水质变化并评估五大连池富营养化程度.结果表明,五大连池不同部分、季节、年份的水质参数指标波动剧烈,可能是受水产养殖及氮、磷浓度变化影响,2池和3池浮游生物量及叶绿素a浓度明显较低;同1980s相比,水质变化较大,一些指标显示水质已趋向好转,但5池却接近重度富营养化,说明近几年的还湿、迁居等保护措施初见效果,但整个湖泊水质恢复需要漫长过程.

As the second largest volcanic avalanche lake in China, Lake Wudalianchi is a representatively natural water body in high latitude region of China, which is a famous and multifunctional natural landscape. For studying the current situation of water quality （WQ） of lake, changes of WQ during the past 30 years and evaluating the eutrophic grade of the lake, we collected and studied 15 WQ indices on 11 sampling sites of Lake Wudalianchi in the spring, summer, autumn during 2012 and 2013. The results showed that, the WQ parameters of Lake Wudalianchi as shallow lake in the temperate continental monsoon climate zone change intensively in different areas and different seasons and years. The plankton biomass and chlorophyll-a concentration from the Second and Third Ponds are lower than those of the Fifth Pond, probably as the results of reduction of phosphorus, nitrogen and incremental fishery production in the formers. Comparison with the lake WQ indices during 1980s, mass of phytoplankton, total phosphorus and total nitrogen concentrations decrease significantly now, noting that WQ may be tending to better status. However trophie level index of Fifth Pond is exceeding 70 with the 3 times of the 1980s, which is adjacent to severe eutrophication status. The environmental safeguards of Lake Wudalianchi such as relocation of residents, returning farmland to wetland are effective at beginning phase, but individual part of lake remains a bad WQ suggesting a long-term treatment required.