Changes and Driving Forces of Farmland Organic Matter in Guangdong Province, China
广东耕地土壤有机质的变化趋势及其驱动力分析

The change of farmland organic matter was analyzed by using long-term monitoring data in Guangdong Province, South China. The results showed that farmland organic matter content in Guangdong Province did not change significantly from 1984 to 2010, but showed a decrease trend in last 5 years, especially for the farmland organic matter in the Pearl River Delta. There were significant differences in organic matter content between different regions: east Guangdong was 22% less than north Guangdong. Soil types affected the organic matter content. Organic matter content in farmland originated from Latosolic red soils and Purplish soils were lower, which were 13.0 g/kg and 11.2 g/kg respectively. The mean of organic matter content of paddy soil which was with the largest area decreased 1.5 g/kg in last 5 years. The decrease of farmland organic matter in Guangdong Province was mainly due to the loss of high-quality farmland and the change of planting model.