湖面亮温对巢湖水华影响的遥感监测分析

利用2002～2007年NOAA气象卫星搭载的先进甚高光谱分辨率辐射计(NOAA/AVHRR)资料,对巢湖蓝藻水华发生频次和湖面亮温的时空分布规律进行统计分析,得到巢湖水体表面亮温的时空分布规律,并探讨其与气温、降水等气象因子以及水华之间的关系和可能存在的机制.从结果来看,湖面亮温与水华发生频次的空间分布规律相近,而在时间分布上存在着较大的差别.一方面,空间分布的相似性表明,湖面亮温高的区域容易发生水华现象;另一方面;时间分布的不一致性表明还有其它的因素会影响水华的发生.通过讨论,得出以下结论:①以5月为分界线,巢湖水华总体上可以分为春季和夏季两大暴发期,春季藻类在较低的水温条件下就能生长繁殖,并暴发水华,但难以形成较大的规模.②受降水量增加的影响,在气温达到最高值的7月不仅湖面亮温所有降低,而且水华发生频次也有所减少.

Analysis of Algae Bloom and Lake Surface Bright Temperature in Chaohu Lake Based on Remote Sensing Data

This article used the remote sensing data from 2002 to 2007 obtained by NOAA/AVHRR to analyze the relationship between algae bloom and lake surface bright temperature in Chaohu Lake. The spatial distribution of Chaohu Lake surface bright temperature was found to be similar to that of the occurrence frequencies of algae bloom. Algae blooms occurred frequently in the region with high bright temperature. In terms of temporal distribution, there was significant difference between the bright temperature and algae bloom, which indicated that the algae bloom could be affected by factors other than the temperature. From the analysis, the following conclusions were drawn. First, the break out season of algae bloom could be divided into spring and summer periods in annual variation, with May as the dividing point. In the spring break out season, the growth and propagation of algae did not depend on the temperature of water, and the affected areas of algae bloom were usually small. Secondly, with the increase of precipitation in July, the bright temperature and the occurrence frequency of algae bloom were decreased.