卫星遥感太湖蓝藻水华分布及其气象影响要素分析

Remote Sensing and Analysis on Meteorological Factors of Blue Algal Bloom in Lake Tai

分析2003—2007年太湖蓝藻水华遥感监测信息指出,近年来,太湖蓝藻水华的时空分布具有如下特征:(1)太湖蓝藻水华爆发的频次和覆盖面积有扩大的趋势;(2)蓝藻水华爆发时间范围有从夏、秋季向温度更低的冬、春季发展的趋势;(3)蓝藻水华爆发频次最高的区域以及爆发最严重的区域主要集中在太湖西部和北部。蓝藻水华爆发的影响要素中除了污染物质的分布,还包括各种气象要素。经过地面气象观测资料与卫星观测资料的对比分析,发现温度、风、光照、降水等气象要素都会对蓝藻水华爆发起到一定程度的影响作用。其中温度、光照因素对蓝藻水华爆发起到促进作用,风、降水因素对蓝藻水华爆发起到抑制作用。同时注意到,由于湖泊污染情况正处在不断变化之中,因而各种气象要素对蓝藻水华爆发的影响程度也在发生着变化。

The remote sensing result of blue algal bloom in Lake Tai from 2003 to 2007 shows that in resent years the blue algal bloom in Lake Tai has the following characters： （1） The frequency and area of the bloom trend increasing; （2） The break out seasons of the bloom is tending to winter and spring; （3） The highest frequency and the most serious areas of bloom appear mostly to be in the west and north of the Lake. Beside the contamination, meteorological characters can also impact on the break out of blue algal bloom. Through the analysis between field measurement and remote sensing data, it was found that the temperature, wind, light and precipitation can all impact on the bloom. In the above four factors, temperature and light have a positive effect while wind and precipitation have a negative effect. It was alto noticed that because of the changing of pollution＇s state, the degrees of effect are also changing.