大气CO2浓度升高对土壤中不同粒级碳的影响  

Effects of CO2 Concentration Increase in the Atmosphere on Carbon in Different Sized Soil Particles

作　　者：马红亮[1,2] 朱建国[1] 谢祖彬[1] 刘钢[1] 曾青[1] 

机构地区：[1]土壤与农业可持续发展国家重点实验室,中国科学院南京土壤研究所,南京210008 [2]福建省亚热带资源与环境重点实验室,福州350007

出　　处：《亚热带资源与环境学报》2006年第1X期33-40,共8页Journal of Subtropical Resources and Environment

基　　金：中国科学院知识创新重要方向项目（KZCX2-SW-440和KZCX2-SW-133）,国家自然科学基金重点项目（40231003）、重大项目（40110817）和重大国际合作项目（40120140817）,973项目（2002CB714003）

摘　　要：不同粒级土壤中的碳有着不同的周转规律，在高CO2浓度条件下，它们含量的变化将在一定程度上反映土壤碳是累积还是减少，对明确土壤碳的变化趋势有重要意义．采用田间培养试验初步模拟研究在高CO2浓度条件下土壤不同粒级碳的分布．结果表明，加入秸秆培养1年，由于CO2浓度升高的原因导致在低氮（LN）、常规氮（NN）和高氮（HN）水平下土壤中碳分别增加0．01、1．10、1．22g／kg，表现为粒级〈53μm土壤颗粒中碳分别增加1．53、2．19、2．70g／kg．粒级〈53μmm土壤颗粒碳量的增加，主要是由于其重量分配百分数显著增加36．2％，碳浓度增加5．4％；粒级〉250μm和250～53μm土壤颗粒部分虽然其碳浓度分别增加20．8％和17．3％（P〈0．05），怛由于重量分配百分数分别显著降低22．8％和36．1％，结果碳量降低．试验表明高CO2浓度导致不同粒级土壤的分配及碳浓度的变化；高氮施肥水平下有增加土壤碳量特别是小粒级土壤碳量的趋势．The carbon in different sized soil particles has different means of turnover. Under the condition of high atmospheric CO2 concentration, the change of carbon content in different sized soil particles partly reflects whether the total carbon accumulation in the soil is increasing or not. Basing on field cultivation experiment and under high CO2 concentration condition, the distribution of carbon content in different sized soil particles was primarily studied. The experiment indicated： after one year of cultivation with the input of straw into the soil, owing to the increase of CO2 concentration, the carbon contents increased by 0.01 g/kg, 1.10 g/kg and 1.22 g/kg respectively for the low nitrogen soil, the normal nitrogen soil and the high nitrogen soil. To be more detailed, for 〈 53μm sized soil particle, the increasing weights of carbon in the soil are 1.53 g, 2.19 g and 2.70 g respectively, and the increasing rate of carbon concentration is 5.4%, mainly due to the 36.2% increase of the weight distribution percentage. For 〉 250μm sized and 250- 53μm sized soil particles, although the carbon concentrations increased respectively by 20.8% and 17.3% （P 〈 0.05）, the carbon weights both decreased because the weight distribution percentage went down respectively by 22.8 % and 36.1%. This research clearly demonstrated that the distribution and concentration of carbon in different sized soil particles both changed obviously under high atmospheric CO2 concentration condition, particularly a prominent increase in carbon content was detected for 〈 53 μm sized soil particle with high nitrogen fertilization level.

关 键 词：大气CO2浓度 田间培养 土壤碳固定 土壤颗粒 稻麦轮作 

分 类 号：S152.4[农业科学—土壤学]