Assecement of the Watersheds in Terms of River Water Quality by Remote Sensing Data (I)

Abstract

The assessment of water quality environment in broad watersheds requires the sufficient understandings of landuse pattern in study areas.The landuse pattern in broad areas can not be analyzed so easily.In this research, the application of satellite remote sensing data (Landsat TM data) to the recognition of landuse pattern was studied and the relation between the area ratio of arable land and the concentration of nitrate nitrogen in the river water in 53 watersheds of Hokkaido was studied;the test areas were Konsen area, Kushiro area and Tokachi area.This research resulted as follows.
1) The accuracy of landcover classification was fairly good, comparing with the landuse statistics of eight counties around study watersheds.
2) The correlation analysis was carried out.The coefficients of correlation were higher than 0.8 in most of the areas.
As a conclusion of this research, the landcover ratios calculated from Landsat TM data are useful for the research on the assessment of water quality environment in broad watersheds.