摘要
云南高原湖泊为社会经济发展提供了重要的淡水资源与生态系统服务功能,然而流域开发的持续与气候极端事件的频发导致了包括异龙湖在内的大中型湖泊出现了水质恶化、藻类暴发与生态环境功能退化。根据1980-2015年35 a的水质监测数据,利用综合营养状态指数(TLI)对异龙湖水质营养状况变化趋势与生态系统响应特征进行评价分析。近35 a来,异龙湖长期处于富营养化过程,水质营养状态可为3个主要阶段。1980-1994年湖泊水质营养状态呈现波动上升趋势,主要是流域农业面源输入造成的;1994-2010年富营养化趋势有所减缓,可能与期间跨流域引水对湖泊营养盐的稀释有关;但2010-2015年又开始明显加剧,主要是流域社会经济持续快速发展造成的工业污染、农业面源污染及湖内沉积物营养盐释放造成的。自1980年以来,异龙湖的水生生物发生了结构性变化,生物多样性丧失严重,主要受湖泊富营养化程度驱动,同时气候变化特别是极端干旱事件对水生生态系统的影响也不可忽视。
Lakes in Yunnan provide important freshwater resources andvital ecosystem service for local development. How-ever, with the intensified anthropogenic disturbance, many lakes have experienced severe threats such as degradation of eco-logical and environmental functioning, and hydrological regulation, in the context of continued warming of regional climate.The monitoring data and water trophic level index(TLI) covering the period of 1980-2015 showed that Yilong Lake experienced long-term process of eutrophication over the last 35 years with three phases identified. During 1980-1994, there was an increasing trend in TLI with fluctuations that was associated with intensified input of pollutants from non-point agricultural sources. This is followed by a moderate decrease in TLI possibly because of cross-catchment water diversion and the dilution effect of lake-water nutrients during 1994-2010. Most recently, the expansion of industrialization, agricultural development and sediment release may have contributed to the acceleration of lake eutrophication. Therefore, the deterioration of water quality, shift of community structure and biodiversity loss was predominantly driven by the lake-water trophic status and the change in regional climate has also modulated the pattern of ecosystem responses since the 1980 s in Yilong Lake.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2018年第S1期281-287,共7页
Environmental Science & Technology
