Soil Fertility in Agroforestry System of Chinese Fir and Villous Amomum in Subtropical China

A trial of interplanting and non-interplanting villous amomum (Amomum villosum Lour.) under the canopy of Chinese fir (Cunninghamia lanceolata Hook.) at age 22 was established in Sanming, Fujian of China, and a survey on soil fertility was carried out 10 years after its establishment. Compared with the control (non-interplanting), the properties of soil humus in agroforestry system were ameliorated, with a higher level of humification and resynthesis of organic detritus. The soil microbial population and enzymatic activities were both higher under the influence of villous amomum. Both the nutrient supplying and nutrient conserving capacities of the soil were improved. This agroforestry system exhibited an advantage of improved soil fertility as well as an accelerated growth of Chinese fir, it was, therefore, a sustainable management system suited for Chinese fir in South China.