Estimation of Vegetation Fractional Coverage in Lugu Lake Based on the Dimidiate Pixel Model

This paper tested the ability of the dimidiate pixel model on extraction of the changes about vegetation fractional coverage vegetation includes all plant communities that cover the earth. Vegetation fractional coverage is an important index to measure vegetation condition. It is important to hydrology and ecology. This paper selected the two phase TM of Lugu Lake area images for the data sources. TM image was used to derive normalized difference vegetation index (NDVI) and vegetation fractional coverage (VFC) by dimidiate pixel model after geometric correction, radiometric correction and atmospheric correction. VFC in different districts of Lugu Lake were calculated in 1995 and 2006 by employing method for dimidiate pixel model. The results show that the vegetation fractional coverage in Lugu Lake area from 1995 to 2006 has changed significantly. The average vegetation fractional coverage raised from 50.94% to 59.82%, rising value is 8.88%. The vegetation fractional coverage of Grass Sea has improved significantly.