红壤丘陵区土壤有机碳储量模拟  

Simulating Soil Organic Carbon Storage and Its Dynamic Changes in a Typical Red Soil Hilly Region

作　　者：解宪丽[1] 孙波[1] 潘贤章[1] 

机构地区：[1]中国科学院南京土壤研究所,江苏南京210008

出　　处：《中国人口·资源与环境》2010年第9期146-152,共7页China Population,Resources and Environment

基　　金：国家重点基础研究发展计划(973计划)项目(No.2005CB121108);国家自然科学基金项目(No.40801081)资助

摘　　要：土壤的有机碳蓄积量及其动态变化,不仅是维持农业生产可持续发展的重要因素,而且在全球变化碳循环研究中具有重要地位。本文基于GIS技术和DNDC模型,以江西省余江县为例,模拟研究了典型红壤丘陵区不同土地利用方式下的土壤有机碳储量及其变化。结果表明:余江县表层土壤有机碳储量为3.52×109kg,平均土壤有机碳密度为4.24 kg m-2。不同利用方式中,灌溉水田的土壤有机碳密度最高,其次是望天田、园地、林地和菜地,旱地的较低,草地的最低。该县土壤有机碳库的年度变化量为8.63×107kg,变化率为+2.45%。土壤有机碳密度下降的地区多位于农田区内,特别是旱地,部分灌溉水田的碳密度略有增加,林地、园地、草地的土壤有机碳密度是增加的,其中园地的增幅最大。在不考虑土壤流失的情况下,自然植被覆盖下的土壤碳截留能力强于农业植被下的土壤,但是灌溉、施肥、种植绿肥等保护性农业措施可以减少土壤碳的损失,甚至增加有机碳的储量。Soil organic carbon（SOC） storage and its dynamic change are not only important factors to maintain agricultural sustainable development,but also play an important role in global carbon cycle.Based on geographical information system（GIS） and soil organic carbon model—denitrification-decomposition model（DNDC）,the SOC storage under different land use types and its annual change in a typical red soil hilly area,Yujiang County in Jiangxi Province,was simulated and analyzed.According to the simulation,the SOC storage in the surface soil horizons of Yujiang County were estimated to be 3.52×109 kg,and the average SOC density was 4.24 kg m-2.The sequence of the SOC densities of different land use types is： irrigated paddy-rice upland-rice orchard forests vegetable land cropland grassland.The annual variation of the SOC storage of Yujiang County was ＋8.63×107kg with an increase of 2.45% without consideration of soil erosion.On the average cropland and vegetable land lost 0.04 kg m-2 and 0.01 kg m-2 respectively,whereas orchard,grassland and forests gained 0.54 kg m-2,0.21 kg m-2,and 0.17 kg m-2 respectively.Land use types and soil management have important influence on soil carbon sequestration.Our results demonstrated that the performance of soil carbon sequestration under natural vegetation is generally higher than that under agricultural vegetation despite soil erosion.For farmland,the source/sink effect of SOC is highly related to the agronomic practices.Conservation managements,such as irrigation,fertilization,and green manure planting,can maintain the storage of SOC.

关 键 词：土壤有机碳储量 DNDC模型 红壤丘陵区 余江县 

分 类 号：S153.6[农业科学—土壤学]