黄土丘陵区表层土壤有机碳沿降水梯度的分布

发布时间：2018-03-05 00:08

本文选题：黄土丘陵区　切入点：有机碳　出处：《应用生态学报》2016年02期 　论文类型：期刊论文

【摘要】：沿368~591 mm降水量梯度选取7个调查地点、共63个调查样点,在每个样点选择恢复年限相近的林地、草地和农地,调查表层(0~30 cm)土壤有机碳的分布特征,分析气候、土层深度和土地利用类型等因素对土壤有机碳分布的影响.结果表明:在黄土丘陵区368~591 mm的降水量范围内,表层土壤有机碳含量表现为草地(8.70 g·kg~(-1))林地(7.88 g·kg~(-1))农地(7.73 g·kg~(-1)),土壤有机碳密度表现为草地(20.28 kg·m~(-2))农地(19.34 kg·m~(-2))林地(17.14 kg·m~(-2)).林地、草地、农地的土壤有机碳含量无显著差异,综合3种土地利用类型的数据分析表明,不同降雨梯度下土壤有机碳含量差异显著(P0.001),土壤有机碳含量(r=0.838,P0.001)与年均降水量间存在显著线性正相关关系;由北向南(以最北端鄂尔多斯为起点),土壤有机碳含量沿着368~591 mm的年均降水量梯度的递增速率为0.04 g·kg~(-1)·mm~(-1),土壤有机碳密度的递增速率为0.08 kg·m~-2)·mm~(-1).年均降水量、土壤黏粒含量、林下枯落物蓄积量和农作物根系密度可较好地模拟表层土壤有机碳分布.
[Abstract]:According to the precipitation gradient of 368,591 mm, 7 investigation sites were selected, a total of 63 survey sites were selected. The distribution characteristics of soil organic carbon (SOC) were selected in each site with similar restoration years, including forest land, grassland and farmland, and questionnaire layer (30 cm), and the climate was analyzed. Effects of soil depth and land use type on soil organic carbon distribution. The content of organic carbon in surface soil was 8.70 g 路kg ~ (-1) 路kg ~ (-1)) in grassland, 7.88 g 路kg ~ (-1) 路kg ~ (-1) ~ (-1) in farmland, and in soil organic carbon density was 20.28 kg 路m ~ (-1) 路m ~ (-2) 路m ~ (-2)). There was no significant difference in soil organic carbon content among forestland, grassland and farmland, and there was no significant difference in soil organic carbon content between forestland, grassland and farmland. The data analysis of three land use types showed that there was a significant linear positive correlation between the soil organic carbon content and the annual precipitation under different rainfall gradients, and the soil organic carbon content was significantly different (P 0.001), and the soil organic carbon content was 0.838% (P 0.001). From north to south (taking Ordos as the starting point, the increasing rate of soil organic carbon content is 0.04 g 路kg ~ (-1) 路mm ~ (-1) along the average annual precipitation gradient of 368g 路kg ~ (-1) mm), and the increasing rate of soil organic carbon density is 0.08 kg 路m ~ (-2) 路mm ~ (-1) 路mm ~ (-1) 路mm ~ (-1). Litter accumulation and crop root density can well simulate the distribution of organic carbon in surface soil.
【作者单位】：中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室;中国科学院大学;北京师范大学地理学与遥感科学学院;中国科学院亚热带农业生态研究所;
【基金】：中国科学院“百人计划”择优支持项目国家自然科学基金重点项目(41530858)、国家自然科学基金项目(41271287)和国家自然科学基金创新研究群体项目(41321001)资助~~
【分类号】：S153.6

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