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Drought is a complex natural disaster that occurs frequently. Soil moisture has been the main issue in remote monitoring of drought events as the most direct and important variable describing the drought. Spatio-temporal distribution and variation of soil moisture evidently affect surface evapotranspiration, agricultural water demand, etc. In this paper, a new simple method for soil moisture monitoring is developed using near-infrared versus red (NIR-red) spectral reflectance space. First, NIR-red spectral reflectance space is established using atmospheric and geometric corrected ETM+ data, which is manifested by a triangle shape, in which different surface covers have similar spatial distribution rules. Next, the model of soil moisture monitoring by remote sensing (SMMRS) is developed on the basis of the distribution characteristics of soil moisture in the NIR-red spectral reflectance space. Then, the SMMRS model is validated by comparison with field measured soil moisture data at different depths. The results showed that satellite estimated soil moisture by SMMRS is highly accordant with field measured data at 5 cm soil depth and average soil moisture at 0–20 cm soil depths, correlation coefficients are 0.80 and 0.87, respectively. This paper concludes that, being simple and effective, the SMMRS model has great potential to estimate surface moisture conditions.

In order to broaden the application of HJ-1 data and better protect the nature reserves of our country, according to the theories and approaches of the ecosystem health and the press-state-response model, the study built the indicators of ecosystem health of nature reserve based on the HJ-1 data. At the same time, by using HJ-1 CCD data, we took Xianghai wetland as an example to extract the indicators. The following results were obtained:(1) The health of Xianghai wetland nature reserve is under threatening. The human activity of it is very common and the function is irrational;(2) The main reasons, cause the damage to wetland ecosystem, are attributed to the increase of human activity and the decrease of precipitation per-year.