植被恢复对岩溶石漠化区土壤有机碳及轻组有机碳的影响

目的]通过分析石漠化治理区不同植被恢复年限对土壤有机碳(SOC)及其组分影响,为该地区石漠化的治理提供一定的基础数据。方法]以重度石漠化土地作为对照,运用空间代替时间的方法,研究了广西壮族自治区平果县果化岩溶石漠化区植被恢复5,10,15,20a后土壤(0—30cm)SOC和土壤轻组有机碳(LFOC)的变化。结果]石漠化土地在进行植被恢复后,SOC和LFOC含量明显增加;植被恢复使表层0—10cm的SOC和LFOC储量明显增加,且随着恢复时间的增长逐渐变大,同时植被恢复对表层(0—10cm)SOC和LFOC储量的影响要远高于下层(20—30cm);植被恢复后LFOC储量的增幅远高于SOC储量。结论]在石漠化区进行植被自然恢复可以有效防止土地石漠化,增加碳的流通。

Effects of Revegetation on Soil Organic Carbon and Light-fraction Organic Carbon in Karst Rocky Desertification Region

Objective] The effects of revegetation on soil carbon(SOC), light-fraction organic carbon(LFOC) was analyzed to provide background data for rocky desertification restoration. Methods] Sites with severe rocky desertification land was taken as contrast and using space as a substitute for time, SOC and LFOC in sites with 5, 10, 15, 20-year restoration in Guohua karst rocky desertification area of Pingguo County, Guangxi Zhuang Autonomous Region were measured and their changes along revegetation were illustrated. Results] SOC and LFOC contents increased obviously after revegetation, especially in 0-10 cm soil layer. The increment of surface soil LFOC storage was much higher than that of SOC storage, suggesting that vegetation restoration on rocky desertification land had a large effect on LFOC. Conclusion] Vegetation restoration can prevent land rocky desertification and increase carbon circulation.