湘中丘陵区不同土地利用方式下土壤有机碳密度  

Study on Soil Organic Carbon Density under Different Land Use Types in Central Hilly Area of Hunan Province

作　　者：方晰[1,2] 徐桂林[1,2] 洪瑜[3] 金文芬[1,2] 

机构地区：[1]中南林业科技大学生态研究室,湖南长沙410004 [2]亚热带森林生态湖南省普通高等学校重点实验室,湖南长沙410004 [3]宁夏农林科学院农业资源与环境研究所,宁夏银川750002

出　　处：《水土保持学报》2009年第1期54-58,63,共6页Journal of Soil and Water Conservation

基　　金：国家野外科学观测研究站项目(20070822);科技部公益性研究项目(2007415);国家林业局项目(2007R23;200508);湖南省教育厅项目(06C923);中南林业科技大学引进高层次人才科研启动基金项目;中南林业科技大学青年基金项目(05044B);2006年度湖南省普通高校青年骨干教师培养对象项目资助

摘　　要：通过实测对比分析了湘中丘陵区不同土地利用方式下土壤有机碳含量及其密度。结果表明,不同土地利用方式下土壤有机碳含量随土壤深度的增加呈指数函数下降趋势(R2≥0.8184),且水平分布上表现为:经济林地(10.12 g/kg)>人工林地(9.94 g/kg)>次生林地(9.11 g/kg)>坡耕地(7.90 g/kg)>弃耕地(6.77 g/kg)>苗圃地(5.95 g/kg);经济林地、人工林地、次生林地土壤有机碳含量与土壤pH值之间存在显著负相关性(p<0.05),6种不同土地利用方式土壤有机碳含量与全氮含量之间均存在极显著正相关性(p<0.01),人工林地和次生林地土壤有机碳含量与硝态氮含量之间存在显著的正相关性(p<0.05),经济林地、弃耕地土壤有机碳含量与碱解氮含量之间存在极显著正相关性(p<0.01),其它4种利用方式与碱解氮含量之间存在显著正相关性(p<0.05);6种不同土地利用方式下土壤(0-60 cm)有机碳密度表现为:人工林地(91.57t/hm2)>经济林地(89.51t/hm2)>次生林地(83.13 t/hm2)>坡耕地(72.70 t/hm2)>弃耕地(58.05 t/hm2)>苗圃地(43.63 t/hm2),与次生林地相比,苗圃地土壤有机碳的损失量最大。Different land use types have an important effect on characteristics of soil carbon, soil quality levels and global warming. Comparative analyses of soil organic carbon （SOC） contents and soil organic carbon density （SOCD） under different land use types in the central hilly area of Hunan province were made. The results showed that the content of soil organic carbon had the exponential function decreasing trend with the increase of soil depth among 6 types of different land use （R^2≥0. 8184）, and decreased horizontally as follows： economic forest-land （10. 12 g/kg）〉 artificial forest-lands （9. 94 g/kg）〉secondary forests （9. 11 g/kg） 〉slope farm land （7.90 g/kg） 〉abandoned farmland （6.77 g/kg） 〉nursery garden （5.95 g/kg） ; and that there was a significant negative correlation between soil organic carbon contents and soil pH value （p〈0.05） in economic forest-land, artificial forest-lands secondary forest land, a highly significant positive correlation （p〈0.01） between soil organic carbon content and total nitrogen contents in the 6 types of land use, a significant positive correlation （p〈0.05） between soil organic carbon contents and soil nitration nitrogen contents in artificial forest-lands and secondary forests, a highly significant positive correlation between soil organic carbon contents and available N contents in economic forest-land and abandoned farmland （p〈 0.01）, and a significant positive correlation in anther 4 types of land use （p〈0.05） ; The density of soil organic carbon went down as follows： artificial forest-lands （91.57 t/hm^2）〉economic forest-land （89.51 t/ hm^2）〉 secondary forests （83.13 t/hm^2）〉 slope farm land （72.70 t/hm^2）〉Abandoned farmland （58.05 t/ hm^2）〉nursery garden （43.63 t/hm^2）. Compared with secondary forest-lands, losses of soil organic carbon density in nursery garden was the most.

关 键 词：湘中丘陵区 土地利用方式 土壤有机碳密度 

分 类 号：S153.62[农业科学—土壤学]