未来温度升高对福建省耕地土壤有机碳的影响研究

Future temperature increased had significant impact to balance of Payments of cropland. The study utilized biogeochemical model DNDC (DeNitrification-DeComposition, 9.5),with the database of 1:50000 for soil database according to the measure values of 15,948 sampling point in year 2008, took five typical county (Tong,an, Pucheng, Wuping, Yongding, and Minhou) in different geographic locations from Fujian Province in subtropical regions as the study area, analyzed the change rule of soil organic carbon in Fujian province and explored the "cardon source/sink" effect of 3 possible atmospheric temperature scenario in soils of Fujian province from 2011 to 2040 . The main research conclusions were as follows: According to the verification result at the regional scale, the results indicated that DNDC model has a good performance on simulating the SOC dynamics for the soils of Fujian province. carbon fixation of soil in Fujian province of temperature increased 2℃ and 4℃ 2 scenarios was 5.62 Tg and 4.27 Tg respectively, the dSOC of cropland were 175.94 kg/hm2,140.54 kg/hm2 and 106.81 kg/hm2. Compared with conventional temperature scenario, the temperature increased 2℃ and 4 ℃ scenario, the fluvo-aquic soils organic carbon decreased 51.00 kg/hm2 and 80.69 kg/hm2 each year respectively. The variable quantity was the greatest change in all soil groups. The coastal soloncharks organic carbon decreased 22.54 kg/hm2 and 54.25 kg/hm2 every year respectively. The variable quantity was the smallest change in all soil groups. The analysis from the soil subgroups. Compared with conventional temperature scenario, the temperature increased 2℃ and 4℃ scenario, grey fluvo-aquic soils and gley paddy soils organic carbon decreased 51.00 kg/hm2 and 102.17 kg/hm2 each year and it is the greatest change in all soil subgroups. Submergenic paddy soils organic carbon decreased 20.20 kg/hm2 and 42.14 kg/hm2 each year in two scenario, and it is the smallest change in all soil subgroups. Temperature increased significantly decreased the "cardon source" capacity of Fujian province cropland. It is important to take reasonable agriculture measures to reduce "cardon sink" effect which caused by temperature increased.