巢湖水华遥感监测与年度统计分析研究

介绍了巢湖蓝藻水华的日常遥感监测方法与流程,开展了基于日常监测的年度统计分析,为水华环境管理提供了科学依据。首先分析了蓝藻水华与正常水体的光谱差异,利用蓝藻水华在近红外波段的"陡坡效应",基于NDVI方法开展水华日常遥感监测。基于日常监测开展水华年度统计分析,获得水华最早发生日期、最晚发生日期、最大发生面积等,并以水华发生频率、水华起始日期和水华持续时间来分析巢湖一年内高发区、发展趋势及持续时间等时空分布规律。研究表明,2010年巢湖水华的高发区域在巢湖西北部水域,水华持续天数最长的区域是巢湖西北和中部部分区域,水华先在西部沿岸聚集,随时间推移向东部和中部扩散,巢湖西南、中部和东南沿岸是最后新增的水华区域。

Monitoring and Annual Statistical Analysis of Algal Blooms in Chaohu Based on Remote Sensing

It was introduced that the method and technological process of algal bloom of Chaohu daily monitoring and annual statistical analysis used remote sensing in order to support the water environment management in China. First, the spectral difference between the algal bloom and the normal water was analyzed and the steep slope effect in NIR band was used in NDVI method to detect the algal bloom in daily monitoring. Then the annual statistical analysis was based on daily monitoring to obtain the earliest date, the late date and the biggest case of area for the algal bloom in Chaohu. The temporal and spatial algal bloom distribution characteristic such as high frequent area, development trend and existence time was analyzed using three parameters: the algal bloom annual frequency, bloom initial date and duration. The results indicated that the most frequency bloom region is northwestern lake, the longest duration region is northwestern and central lake, and bloom began in western areas, developed to eastern and central areas and appeared in the southwestern and southeastern areas lastly.