基于MODIS数据的太湖蓝藻变化与水温关系研究  

Research on Relationship Between Cyanobacteria Bloom and Water Temperature in Lake Taihu Based on MODIS Data

作　　者：姜晟[1,2] 张咏[2] 蒋建军[1] 金焰[2] 

机构地区：[1]南京师范大学地理科学学院,江苏南京210046 [2]江苏省环境监测中心,江苏南京210036

出　　处：《环境科技》2009年第6期28-31,共4页Environmental Science and Technology

摘　　要：以太湖为研究区,基于2008年4～12月的60景EOS-MODIS1B遥感影像数据,利用NDVI算法结合目视判读解译了水华分布变化的基本信息,通过劈窗算法反演太湖湖面水温,发现在2008年太湖蓝藻生长、暴发、衰退周期中,水华面积的大小与湖面均温值之间关系密切:在20℃以下时表层水温与太湖蓝藻生长暴发或沉寂消亡具有明显的相关性;20℃～30℃时水华的面积大小受到湖面温度和其他因素的共同影响,容易发生大规模蓝藻暴发;30℃以上时过高的表层水温会对蓝藻的上浮聚集具有一定抑制作用;太湖蓝藻全年消亡的临界温度与其初始生长的临界温度相比更低。研究同时发现太湖湖面温度的空间差异是影响蓝藻水华分布迁移的重要因素之一。Speetral characteristic of all the cloudless 60 EOS-MODIS imageries during April and December in 2008 was analyzed in Lake Taihu, and the information of cyanobaeteria bloom distribution and migration was extracted by the algoritbm of Normalized Difference Vegetation Index （NDVI）. In order to find out the temperature effect on cyanobacteria bloom temporal and spatial variation, the relationship between water temperature and cyanobacteria bloom was analyzed based on flock of data. On the basis of the synchronous water temperature data retrieved by split-window algorithm, the statistics showed that there was a close relationship between the acreage of eyanobacteria bloom and the average water surface temperature. When the water temperature was below 20℃, it had obvious correlation with cyanobacteria bloom growing or falling off. When the temperature ranged from 20℃ to 30℃, it would become an important environment factor and cyanobacteria bloom occurred with higher possibility. When the temperature was above 30℃, it might inhibit cyanobacteria bloom. The critical temperature of cyanobactcria bloom dying off was lower than its germination temperature. It was also found that the spatial difference of water temperature was one of the important factors which influenced the distribution and migration of cyanobacteria bloom in Lake Taihu.

关 键 词：MODIS 太湖 蓝藻水华 水温 

分 类 号：X5[环境科学与工程—环境工程]