利用植被覆盖度—地表温度特征空间提取厦门市土壤湿度信息

Extracting Soil Moisture from Landsat Imagery of Xiamen City Using a Spectral Feature Space Composed of Fractional Vegetation Cover and Land Surface Temperature

土壤湿度是水文学、气象学以及农业科学研究领域的一个重要参数。利用1989年和1996年两个时相LandsatTM遥感卫星影像来获取厦门的植被覆盖度和地表温度,并由此构建了植被覆盖度和地表温度组成的特征空间,最后利用该特征空间反演了土壤湿度,并分析湿度在两个时相中的变化情况。结果显示,在所研究的时间段内,厦门西南老城区的湿度得到增加。但是在东北部城市建成区扩展的地区,土壤湿度则明显降低。

Soil moisture is an important variable in hydrology, meteorology and agriculture science. In this study,two Landsat TM images of Xiamen city were used to evaluate soil moisture of the city for the years of 1989 and 1996. The extraction of the moisture was based on a spectral feature space composed of fractional vegetation cover and land surface temperature. Furthermore, the change of soil moisture of Xiamen city during the study period was also detected. The study revealed that the moisture of the downtown area in the southeast of Xiamen has increased,while the moisture in the north area was significantly reduced, which is due largely to the urban expansion to this area during the period.