Soil Organic Carbon And Its Influence Factors In Phyllostachys Forests Of Dagangshan,Jiangxi Province

In order to reveal the effect of soil properties on soil organic carbon(SOC),the relations between SOC content and soil properties under Moso bamboo were studied through path analysis in Dagang mountain of Jiangxi Province.The results showed that the variation range of soil organic carbon content was from 12.98g/kg to 56.17g/kg,which belong to the middle level of variation,and there were significant differences;the variation range of soil bulk density was from 0.73g/cm3 to 1.31g/cm3,the condition of soil porosity was proper,the variation range was from 52.31%to 62.69%,and the variation range of field capacity was from 33.23%to 68.37%.The variation coefficient of all of three factors were lower than 10%,which belong to the low level of variation,but there were still significant differences;the content of total nitrogen and alkali hydrolyzable nitrogen in soil were very high,but the contents of other nutrients such as available phosphorous and quick-acting potassium were quit low.Most of soil chemical properties belong to the middle level of variation,there were significant differences on alkali hydrolyzable nitrogen of different sample plot.Almost all the soil enzyme activity showed the same trend with the change of organic carbon content.There was no significant difference in soil enzyme activity between different plots,and the variation was between middle level and strong level.Path analysis showed that the influence mechanism of soil properties on SOC content were different.Alkali-hydrolyzable nitrogen content and field capacity promoted the content of SOC mainly through direct effects.The activities of ?-glucosidase,polyphenol oxidase and invertase affected the content of SOC mainly through indirect effects with alkali hydrolyzable nitrogen.Although both of bulk density's direct effects and indirect effects were low,the combined action could not be ignored.Total porosity showed similar degree of strong positive indirect effects and negative direct effects.All selected factors of soil jointly explained 90.36%of SOC contents variability.