摘要
通过地面调查研究不同封育管理措施对甘肃景泰绿洲边缘沙质草地土壤轻组及全土碳氮储量的影响。结果表明,在天然封育和人工抚育措施实施后,研究区沙质草地0-40cm层土壤轻组及全土碳氮含量、单位面积有机碳和全氮储量都明显增加(P<0.05)。(1)和流动沙地相比,封育19年(人工抚育19年)、封育19年(人工抚育5年)、封育10年(自然恢复)沙质草地0-40cm层土壤轻组干物质量分别增加170.8%,150.0%,129.2%,0-40cm层土壤有机碳和全氮平均含量分别增加372.7%和266.7%,190.9%和183.3%,136.4%和91.7%,土壤轻组干物质量与全土有机碳和氮含量呈高度正相关(r=0.95**)。(2)和流动沙地相比,封育19年(人工抚育19年)、封育19年(人工抚育5年)、封育10年(自然恢复)沙质草地0-40cm层土壤轻组碳和氮储量分别比流动沙地增加422.7%和280.7%,345.7%和232.1%,244.4%和152.1%;全土碳和氮储量分别比流动沙地增加了261g/m2和20g/m2,143g/m2和15g/m2,101g/m2和7g/m2。(3)土壤轻组碳(氮)占全土碳(氮)储量的比例以封育沙质草地高于流动沙地;各封育沙质草地和流动沙地中轻组碳占全土碳的比例都高于轻组氮占全土氮的比例。(4)天然封育+人工抚育措施对沙质草地的影响和改善程度高于纯天然封育措施,它是促进我国北方退化沙质草地恢复的适宜方法。
Using a field investigation data, difference of light fraction and total organic carbon and nitrogen stores of sandy grassland soil as affected by different exclosure management was compared in Jingtai county. The results were as follows： The content of light fraction and total organic carbon and nitrogen, the unit area of organic carbon and total nitrogen stores increased significantly in 0--40 cm soil layer of sandy grassland（P d0.05）. （1）Compared with the mobile sand, the content of light fraction dry matter in 0--40 cm soil layer of 19-year-old exclosure （19-year-old artificial restoration）, 19-year-old exclosure （5-year-old artificial restoration）, 10-year-old exclosure（natural restoration） increased 170.8%, 150.0%, 129.2%, respectively. The content of soil organic carbon and total nitrogen increased 372.7% and 266.7%, 190.9% and 183.3%, 136.4% and 91.7%, respectively. There was a strong positive relationship between light fraction dry matter and soil organic carbon or total nitrogen（r=0.95＊＊）. （2）Compared with the mobile sand, the stores of light fraction soil organic carbon and nitrogen in 0--40 cm layer of 19-year-old exclosure （19-year-old artificial restoration）, 19-year-old exclosure （5-year-old artificial restoration）, 10-year-old exclosure （natural restoration） increased 422.7% and 280.7%, 345.7% and 232.1%, 244. 4% and 152.1%, respectively. The stores of total organic carbon and nitrogen increased 261 g/m2 and 20 g/m2 , 143 g/m2 and 15 g/m2 , 101 g/m2 and 7 g/m2 , respectively. （3）The ratio of soil light fraction organic carbon（nitrogen） and total organic carbon（nitrogen）, the exelosure sandy grassland was higher than that of the mobile sand. In every exclosure sandy grassland and mobile sand, the ratio of light fraction and total organic carbon was higher than the ratio of light fraction and total nitrogen. （4）The exclosure sandy grassland（artificial restoration） had better improvement on soil light fraction and total organic carbon and nitrogen stores compared to sandy grassland restored by only natural force. It was an appropriate method for degraded sandy grassland to recover in northern China.
出处
《水土保持学报》
CSCD
北大核心
2013年第1期252-257,共6页
Journal of Soil and Water Conservation
关键词
沙质草地
封育
轻组有机碳
碳氮储量
sandy grassland
exclosure
light fraction organic carbon
stores of carbon and nitrogen
