台湾基隆河流域水质与环境遥感制图及分析

The Water Quality and Environment Background Remote SensingMapping and Analysis in Jilong River Watershed, Taiwan

本文利用ＴＭ 影像和ＳＰＯＴ影象， 在地图资料、统计资料以及实测资料的基础上，进行了基隆河流域环境遥感制图， 并根据遥感影象灰度值与水体反射率和水中悬浮固体含量之间的相关关系，运用ＳＰＯＴ影象和实测数据将基隆河悬浮固体含量分为４ 级。通过水体悬浮固体浓度等级与环境背景的比较， 并通过计算各等级水体与各种环境背景相邻的边界长度， 得出基隆河悬浮固体含量与其环境背景有关， 植被覆盖好的山区林地， 河流水体悬浮固体含量低，植被覆盖率低的城区水体悬浮固体含量高。

With the development of the remote sensing, it became more and more important in environmental monitoring. Especially in water quality remote sensing and environment background mapping, there has been a lot of work to be done. But water quality is relative to the environment and human's activities. The suspended sediment is one of the most important aspect of the water quality, so in this paper, some work about environmental background mapping and its relationship to the suspended sediment in Jilong River, Taiwan, is done. First, according to the suspended sediment concentration measured in field and the standard provided by Environment Office of Taiwan, the river suspended sediment concentration is divided into four levels. The grades of all the river are acquired by use of maximum likelihood classification of SPOT band 1 and 2. Then, the environmental background is acquired by supervised classification with TM and SPOT images based on the landuse map and other statistical information. The predominant background is forest, about 41% of the total area. The suspended sediment map and the environmental background map of Jilong River show that the suspended sediment concentration is lower in upper reaches of the river where the land is mainly forest, while it is higher in lower reaches of the river where the river flow through the city. By calculate the proportion of the length of every grade of water bordering upon every kind of environment background, we find that the suspended sediment concentration is related to the land cover and city pollution. The source of the suspended sediment is mainly the polluted warter poured from the city.