Soil Organic Carbon Content And Its Controlled Factors From Different Soil Types In Mt.wuyi

In this research we investigated that soil organic carbon (SOC) content and its controlled factors, dynamics of SOC and decomposition of new C addition, soils were collected from different soil types of Mt. Wuyi. The purpose was to provide scientific data for carbon cycle in the mountain soil. The major results were summarized as follows:The contents of SOC had a trend of red soil<yellow soil<meadow soil along with altitude, and its value ranged from 14.91 g-kg-1 to 112.34 g-kg-1. A positive correlation was found by analysis between SOC and the total N, available N, available P, available K and soil silt content. SOC contents increased with the altitude rise, but decreased with the annual average temperature rise.The organic carbon content was higher in soil with straw addition (RR) than in the control soil (CK) under 15℃and 25℃incubation condition at 360 d (D sample exception). It indicated that the straw addition was helpful to the soil native carbon turnover. Compared with 15℃incubation condition, the SOC content at 25℃incubation condition was more lower, suggesting that temperature increase stimulated the SOC decomposition. At 360 d, the ratios of organic carbon increase were-1.60% to 6.44% and-1.43% to 5.63% under 15℃and 25℃incubation conditions, respectively.The residual coefficient of straw carbon in soil decreased with incubation time, and there was a tread at 25℃<15℃incubation condition (at incubation 240 d F sample exception), indicating that temperature increment was advantageous to the straw carbon decomposition. At 360 d, the residual coefficient of straw carbon accounted for 0.13 to 0.35, which meant about 13% to 35% straw carbon had not yet decomposed when incubation experiment ended.