摘要
利用农业生态系统生物地球化学模型(DNDC)方法,在GIS区域数据库支持下运行模型,研究了东北三省地区土壤有机碳储量状况,及其在现行农田管理措施下的变化特征。结果表明,以1998年为例,东北三省耕地土壤有机碳(SOC)储量(0-30cm土层)约为124 348万t,黑龙江、吉林和辽宁省分别占58.4％、25.5％和16.1％;在目前的农作制度下土壤有机碳库处于严重的负平衡,每年净丢失有机碳3122万t,黑龙江、吉林和辽宁省分别占59.3％、25.9％和14.8％;单位面积耕地SOC年减少量高达2.05 t·ha-1,黑龙江、吉林耕地SOC丢失最严重。增加秸秆还田比例,提倡免耕和人畜粪便还田,增施有机肥都有助于土壤有机碳的积累和有效地保持土壤有机碳平衡。
This paper aims at estimation of the soil organic carbon (SOC) storage in Northeast China, identification of its balance situation and changing trends under current cropping systems, and finally put forward some strategies to keep the soil organic carbon in balance. A biogeochemical model (DNDC) for agro-ecosystem was employed to predict soil organic carbon dynamics in agricultural ecosystems at regional scale. Data on climate, soil properties, cropping systems, acreage, and management practices at county scale were collected from various sources and integrated into a GIS database to support the model runs at the regional scale. The model predicted results revealed: Total soil organic carbon storage in agricultural lands in 3 provinces in Northeast China is about 1 243.48 ×106t (0-30 cm soil layer), and Heilongjiang, Jilin and Liaoning province respectively occupied by 58.4%,25.5% and 16.1% ; Under the current cultivation, soil organic carbon is in a situation of negative balance with losing carbon at a high rate of 31.22 ×106 t·yr-1 (Heilongjiang, Jilin and Liaoning Province respectively occupied by 59.3%,25.9% and 14.8%) and 2.05 t·ha-1·yr-1, especially serious in Heilongjiang and Jilin provinces. Protective cultivations, such as manuring, returning more residue of crops to the field, adopting no-till, are very useful for accumulation of soil organic carbon in this area.
出处
《中国农业科学》
CAS
CSCD
北大核心
2004年第8期1166-1171,共6页
Scientia Agricultura Sinica
基金
国家"十五"科技攻关重大资助项目(2002BA516A08)
