Impacts of Rubber Plantation Intercropping toLitter,Humus and Soil Property

The investigation results showed that intercropping increased litter accumulation on soil surface obviously.The amount of litter on the soil surface in plantations of rubber+ Alpinia villosum ,rubber+coffee and pure rubber plantation were 3653.5,2861.1 and 1934.3 kg/hm 2 respectively.Intercropping increased organic matter on soil surface,and in 0～5cm soil surface layer of the 3 plantations,the amount of organic matter were 44.303,32.905 and 26.840 g/kg respectively.In the 3 plantations,most of the humic acid is fulric acid.Intercropping with Alpinia villosum and coffee was suitable for the formation of humic acid.Intercropping improved soil properties,in the soil layer of 2～5 mm the stable granular structure of the soils in the 3 plantation were 30.89,13.66 and 12.13% respectively.Rubber trees intercropping with Alpinia villosum was the best to improve soil fertility.