摘要
【目的】探求青藏高原高寒草甸高山流域土壤有机碳含量的空间分布规律,为全球变化和退牧还草背景下区域有机碳含量估算及生态环境评价提供参考。【方法】选取青藏高原中部纳木错典型冻土小流域,在该流域不同海拔、坡向分别采集浅层(0~10 cm)和根系底层(20~30 cm)的土壤样品,测定不同海拔、坡向和土层间的土壤有机碳含量,并分析其空间分布规律。【结果】研究区土壤有机碳含量介于0.95~47.28 g/kg,平均为13.44 g/kg,随海拔升高呈降低趋势;不同坡向土壤有机碳含量表现为北向坡最高(16.41 g/kg),南向坡最低(8.47 g/kg),东向坡(12.10 g/kg)和西向坡(12.17 g/kg)居中且较接近;浅层(0~10 cm)土壤有机碳含量(20.01 g/kg)较根系底层(20~30 cm)土壤有机碳含量(6.88 g/kg)高。【结论】纳木错流域土壤有机碳含量与海拔、坡向和土层深度等因素显著相关,流域平均含量较青藏高原其他地区低。
【Objective】This study aimed to explore soil organic carbon(SOC)spatial distribution regulations in high mountain alpine meadow basins of Qinghai-Tibet Plateau for a better estimating of SOC content and its variation trends under the background of global change and grassland restore.【Method】Surface layer(0-10 cm)and bottom layer(20-30 cm)soil samples at different elevations and slope directions were collected to determine SOC contents at different elevations,slope directions and soil layers in a typical catchment in Namco Basin which located in middle part of the Qinghai-Tibet Plateau.Spatial distribution characteristics of SOC in the catchment were analyzed thereafter.【Result】SOC of the study area were between 0.95-47.28 g/kg,with the mean value of 13.44 g/kg.SOC showed a decreasing tendency as elevation rose.Compared among different slope directions,SOC displayed higher values on northern slopes(16.41 g/kg)and lower values on southern slopes(8.47 g/kg).SOC have similar values between eastern(12.10 g/kg)and western(12.17 g/kg)slopes.Besides,SOC presented higher values in 0-10 cm shallow layers(20.01 g/kg)than 20-30 cm bottom layers(6.88 g/kg).【Conclusion】SOC are significantly correlated to elevation,slope direction and soil layer in the study basin.Mean SOC content of the Namco Basin is lower than most of areas of the Qinghai-Tibet Plateau.
出处
《南方农业学报》
CAS
CSCD
北大核心
2017年第12期2152-2156,共5页
Journal of Southern Agriculture
基金
国家自然科学基金项目(41401247
41371087)
关键词
土壤
有机碳
空间分布
纳木错流域
soil
organic carbon
spatial distribution
Namco Basin
