保护性耕作对黄土高原玉米-小麦-大豆轮作系统产量及表层土壤碳管理指数的影响  

Effects of conservation tillage on crop yield and carbon pool management index on top soil within a maize-wheat-soy rotation system in the Loess Plateau

作　　者：杨晶[1] 沈禹颖[1] 南志标[1] 高崇岳[1] 牛伊宁[1] 王先之[1] 罗彩云[1] 李光棣 

机构地区：[1]兰州大学草地农业科技学院,农业部草地农业生态系统学重点开放实验室,甘肃兰州730020 [2]澳大利亚新南威尔士州初级产业部Wagga Wagga农业研究所,Wagga Wagga,澳大利亚,新南威尔士2650

出　　处：《草业学报》2010年第1期75-82,共8页Acta Prataculturae Sinica

基　　金：国家重点基础研究发展规划(G2000018602、2007CB106804);澳大利亚国际农业研究中心项目(LWR21999/094);教育部2003年重点科技项目资助

摘　　要：在陇东黄土高原雨养农业区,以传统耕作(t)为对照,研究了3种保护性耕作:耕作+秸秆覆盖(ts)、免耕(nt)、免耕+秸秆覆盖(nts)对玉米-大豆-小麦轮作系统产量和土壤全氮、全碳、有机碳,易氧化有机碳及碳库管理指数的影响。结果表明,从2001至2007年,10茬作物的总产量在ts、nts处理下分别比t提高3.63和1.62t/hm2,而nt处理则比t处理显著降低2.48 t/hm2。7年后,tt、s、nt和nts处理表层土壤全氮含量分别提高15.4%,30.2%,16.2%和49.5%。总有机碳含量相应提高2.5%,18.7%,11.7%和74.0%,易氧化有机碳含量在ts,nt和nts处理下分别比t处理提高16.0%,16.2%和38.1%;土壤碳氮比在tt、s、nt和nts处理下较之7年前分别降低了11.41%,8.54%,3.91%和2.72%,ts、nt和nts处理下碳库管理指数分别比t处理提高12.6%,20.1%和46.6%,说明秸秆覆盖+免耕均有利于提高该轮作系统中土壤有机碳含量并改善碳库质量。The effects of conventional tillage （t）, conventional tillage with stubble retention （ts）, no-tillage （nt）, and no-tillage with stubble retention （nts） treatment on crop yield,soil total nitrogen and carbon, total organic carbon, oxdizible organic carbon, and carbon pool management index （CPMI） were investigated within a maize-wheat-soy rotation system in the western Loess Plateau. Total crop yield for ten harvests during the years 2001 to 2007 under ts and nts treatments increased by 3.63 and 1.62 g/kg compared with conventional tillage, but decreased by 2.48 g/kg on the nt treatment. Total nitrogen contents under nts treatment were 15.4%, 30.2% and 16.2% higher than t, ts and nt treatments. Total carbon under nts treatment was signifi- cantly increased by 2.04 g/kg and total organic carbon were 2.50, t. 56 and 1.70 g/kg higher than under t, ts and nt treatment, respectively. Easily oxdized organic carbon under nts was 2. 13 g/kg higher than under t treatment. TN/TC decreased by 12.75%,15.97%,6.87% and 24. 16% under t, ts, nt and nts treatments. The CPMI under ts, nt and nts were 12.6%,20.1% and 46.6% higher than under t, both stubble retention and no-till were beneficial to increasing the soil organic carbon content and improving the quality of the carbon pool.

关 键 词：秸秆还田 免耕 有机碳 易氧化有机碳 碳氮比 

分 类 号：S345[农业科学—作物栽培与耕作技术]