环境一号卫星是我国2008年自主发射的环境与灾害监测小卫星,其2d的时间分辨率使其成为环境变化监测的重要数据源.根据实测的太湖、巢湖、滇池和三峡水库的水面光谱信息以及水质参数,构建基于环境一号卫星多光谱数据的富营养化评价模型,对太湖、巢湖、滇池和三峡水库2009年水体营养状况进行了评价分析.研究结果表明:利用环境一号卫星CCD(电荷耦合器件图像传感器)数据可以较为准确地评价内陆水体富营养化状态(研究区最大平均相对误差为23.2%,最小平均相对误差为6.8%);太湖在2009年初81.09%的水体呈中营养状态,而在4、5、6、9和11月份时水体处于富营养化状态,且中度富营养化状态占到了水体面积的85.75%;巢湖和滇池全年处于富营养化状态,且两湖的主要水域在大多数时间里都为重度富营养化状态,所占平均面积分别达到了66.67%和89.75%;此外,滇池的富营养化状态不同于太湖和巢湖先升高再降低的年内变化趋势,而是在年中的5~9月份出现富营养化状态降低的情况;三峡水库基本上处于贫营养和中营养状态之间,水库水位与水华面积存在显著的负相关关系(r=-0.818),表明水库的营养状态与其蓄水量的关系密切.
The Chinese domestic satellite HJ-1 was launched in 2008. Because of its 2-day temporal resolution,it has become a significant resource for environment and disaster monitoring. Based on the in situ measured data,which are spectral reflectance and water quality parameters in Lake Taihu,Lake Chaohu,Lake Dianchi and the Three Gorges Reservoir,eutrophication evaluation models were developed. The models were based on the band settings of the HI-1 CCD images,and were used to quantify the nutritional status of these waters in 2009. The models have high accuracies with maximum mean relative error of 23.2%,and a minimum value of 6.8%. At the beginning of 2009,81.09% of the water area in Lake Taihu was mesotrophic,while the whole water area exhibited eutrophic status in April,May,June,September and November. And 85.75% of the whole water area was moderately eutrophic. Lake Chaohu and Lake Dianchi were eutrophic throughout the whole year. 66.67% and 89.75% of mean area of Lake Chaohu and Lake Dianchi were hypertrophic in most of 2009. During the year,the eutrophication of Lake Taihu and Lake Chaohu increased firstly,and then decreased. Conversely,the eutrophic status of Lake Dianchi decreased from May to September and the nutrition status of the Three Gorges reservoir was between oligotrophic and mesotrophic. And we also found that there was a significant negative correlation between water levels and the areas with alga blooms,with an r of-0.818. This indicates that the nutrition status of the reservoir is closely related to the impoundage.