太湖藻华水体的遥感监测与预警

受水体富营养化的影响,藻华暴发已成为目前我国湖泊和水库面临的主要环境问题之一.针对藻华水体的动态监测,特别是提前预警技术的研究对于内陆水体的污染防控具有重要意义.该文结合高光谱实验数据,综合运用指数法和遥感影像假彩色合成法.建立了基于MODIS数据的太湖藻华水体遥感信息提取模型,并在此基础上,对2007年3～5月间太湖藻华形成过程进行了遥感实时动态监测研究.通过埘春夏季节蓝藻水华的空间分布特征和藻华不同形成阶段的特征分析,提出了太湖藻华水体预警的技术方法,即当MODIS水体绿度指数GI集中分布于0.6～0.8区间时,可认为太湖水域已进入蓝藻水华大规模暴发前的预警阶段.

Remote sensing monitoring and pre-alarming of algal blooms in Taihu Lake

The explosive growth of algae in inland water bodies is one of the major water environmental problems in China, and it's very important to monitor the dynamic of algae in both temporal and spatial scales. In the present paper, a model, which was used to extract the algae information from the water body of Taihu Lake using MODIS data, was established based on the remote sensing index and image false color composite methods. Using this model, we studied the algae explosive growth formation process between March and May in 2007. Through the analysis of the temporal and spatial distribution features of the algae outbreak between the spring and summer seasons, an early warning method of algal blooms was proposed, that is, when the MODIS green index mainly concentrated in the range between 0. 6 and 0. 8, the water body of Taihu Lake can be considered to have been in the early alarming stage of algal blooms.