Dynamic estimation model of vegetation fractional coverage and drivers

Abstract

This research reveals major changes of VFC and drivers in 2000 to 2010 in Guangdong province, China. Using MODIS NDVI, VFC directly calculated. Spatial patterns of VFC changes classified into four levels such as low (<50%), medium (50-70%), high (70-90%) and very high (>90%) in 2000, 2005 and 2010 separately. Time series of VFC showed the fitting curve is a straight line of value 0.783 (78.3%). Results showed that level >90% has highest mean of change annually, with values between 3.89% to 21.44% and level <50% has the lowest mean among all levels. The values of level 50-70% are between 7.79% and 19% and values of level 70-90% are between 68.38% and 77.25%. Trend analysis of VFC showed that in the northern mountainous regions, the economy is undeveloped and there is less human disturbance, leads to having higher VFC. In the southern coastal parts, human disturbance such as industrialization and urbanization can be seen, leads to having low VFC. Plus, using DMSP/OLS, CNLI computed. The driving factors of VFC dynamics considered human activities and climatic factors and finally Pearson correlation coefficient confirmed the relationship between VFC, climatic factors and CNLI. Result showed that VFC is positively correlated with sunshine hour, but VFC is not related to CNLI indicates that at provincial scale over research period of about 10 years, Even though urbanization and industrialization had a defined impact on the change of VFC in some cases.