未来30年川东平行岭谷区县域农田SOC动态模拟  

Dynamic simulation of farmland SOC in parallel ridge valley area in eastern Sichuan in the next 30 years

作　　者：张琳 邵景安[1] ZHANG Lin;SHAO Jing’an(Department of Geography and Tourism, Chongqing Normal University / Key Laboratory of Surface Processes and Environmental Remote Sensing in the Three Gorges Reservoir Area, Chongqing 400047, China)

机构地区：[1]重庆师范大学地理与旅游学院/三峡库区地表过程与环境遥感重庆市重点实验室,重庆400047

出　　处：《中国生态农业学报》2017年第12期1848-1857,共10页Chinese Journal of Eco-Agriculture

基　　金：重庆市基础科学与前沿技术研究专项(cstc2017jcyj B0317)资助~~

摘　　要：以位于川东平行岭谷的典型县——垫江县为研究对象,探讨在特定气候模式下未来30 a研究区农田土壤有机碳(SOC)及其动态变化,为研究区未来耕地可持续利用与管理提供数据支持和科学依据。利用生物地球化学模型DNDC,选取IPCC AR4报告中的BCCR_BCM 2.0的B1模式,在基于研究区土壤性质和农业管理制度等建立的GIS区域数据库的支持下,模拟研究区2011—2041年SOC动态变化。结果表明:1)DNDC模型能够较好地模拟特定气候条件下SOC及其动态变化,模拟值和观测值的相关系数r为0.981,达到0.01水平下的极显著相关关系;模拟值和观测值的RMSE值为16%,模拟结果较好。2)未来30 a研究区农田0~20 cm土层SOC密度和储量均呈显著增加态势,单位面积碳增量2 637.07~8 091.55 kg(C)·hm^(-2),增幅为10%~34%,新增固碳量2.7×10~5~8.3×10~5 t,年均增速87.9~269.7 kg(C)·hm^(-2)·a^(-1)。3)未来30 a川东平行区县域农田土壤总体呈持续碳增汇状态,研究区固碳、丢碳以及相对平衡三者间的差异将逐渐凸显。The relationship between greenhouse gas emission reduction and soil carbon sequestration has become the focus of global climate change research amidst the worsening global climate change.As a core interface of terrestrial ecosystem,farmland soils have a huge potential to sequester carbon.Exploring the response and feedback of the dynamic balance of farmland soil organic carbon(SOC)to global climate change is significant in understanding the relationship between global carbon cycle and agricultural ecosystems.Dianjiang County is a typical representation of parallel ridge valley area in eastern Sichuan.It is an important grain and oil producing area in Chongqing.In the process of transformation from traditional to modern agriculture,the area has been faced with double pressures of food security and increasing farmland SOC.Therefore in this region,it is very important to study farmland SOC and its dynamic change using specific climate model in the next30years.It provides data support and scientific basis for sustainable utilization and management of future cultivated lands in the study area.Supported by GIS regional database established for soil properties and agricultural management system,this study simulated the dynamic change in SOC in the study area for the period2011-2041using the biogeochemical model DNDC.The study also used the B1climate model within BCCR_BCM2.0in the IPCC AR4report.The results showed that:1)The DNDC model fairly simulated farmland SOC and dynamic change under specific climate conditions.The correlation coefficient between the simulated and measured values was0.981,which was significant at the0.01confidence level.The RMSE value of the simulated and measured values was16%,indicating better simulated results.2)The SOC density and storage in the0-20cm soil layer in the study area significantly increased for the next30years.The increase in carbon per unit area was2637.07-8091.55kg(C)·hm-2or10%-34%,that in carbon sequestration was2.7×105-8.3×105t,and that in average increase rate was87.9-269.7

关 键 词：农田土壤 土壤有机碳 DNDC模型 动态模拟 固碳量 川东平行岭谷区 

分 类 号：K903[历史地理—人文地理学]