Investigation of the Surface Condition in Taklimakan Desert

Abstract

The results of in situ survey in the selected places in the periphery of Taklimakan Desert are described with an emphasis on the relationship between spectral reflectance and soil moisture contents.
It is found that there is inverse relation between the spectral reflectance and soil moisture content, and it is found that soil moisture content can be estimated from the value of spectral reflectance. The results of in situ measurement indicate that the average reflectance of the soil in the periphery of Taklimakan is 21% in the visible spectrum, and 29% in near infrared spectrum respectively. If short wave infrared spectrum (up to 2, 500 nm) is included it rises up to 38%. It is also found that reflectance of dry soil in near and short wave infrared is nearly 10% higher than that in the visible spectrum.
In Hotan area, the day time surface temperature reached as high as above 42°C in late October while below the surface, soil temperature dropped sharply reaching 20°C at 5 cm depth. Large radiation cooling was observed at night reaching as low as 2 °C at the ground surface.