摘要
水热条件、土壤性质和耕作管理影响了土壤的硝化作用从而影响农田氮素循环和平衡.本试验选择中国东部3个气候带上的主要农田土壤:中温带黑龙江海伦的黑土、暖温带河南封丘的潮土和中亚热带江西鹰潭的红壤,在上述3个地点的生态试验站建立土壤置换试验,对比研究不同水热条件和土壤类型对玉米单作系统中土壤硝化作用的交互影响.2006～2007年的试验结果表明,在玉米抽雄期,从海伦到鹰潭(月均温由22.3℃上升到26.8℃,月降水由100.8 mm增加到199.6 mm),3种土壤的硝化作用强度均随着月均温和月降水的增加而下降,黑土、潮土和红壤分别下降了64.2%～67.2%、52.1%～52.5%和41.7%～75.2%,土壤的硝化作用强度与气温(r=-0.354,p<0.01)和降水(r=-0.290,p<0.01)均呈极显著负相关.土壤类型也显著影响了土壤硝化细菌的数量和硝化强度,硝化细菌数和硝化强度的大小顺序为:潮土>黑土>红壤.土壤pH对土壤硝化强度有显著影响,其相关系数r=0.551(p<0.01).总体上,在玉米抽雄期,区域水热状况及土壤类型、施肥均影响了土壤的硝化强度,水热×土壤类型、水热×施肥、土壤类型×施肥、水热×土壤类型×施肥等对硝化强度有着极显著的交互作用.
Climate conditions, soil properties and management practices control soil nitrification process which affects nitrogen cycling and balance in agro-eeosystems. The interaction of temperature, rainfall, soil type and fertilization on the soil nitrification process was studied by a soil transplantation experiment installed in 3 experiment stations of Chinese Ecological Research Network, i.e. Hailun, Fenqiu and Yingtan Agroecological Experiment Station, which represents middle temperature, warm temperature and middle subtropical zone, respectively. Three types of cropland soils were selected, i.e. neutral black soil （Phaeozem）, alkaline Chao soil （Cambisol） and acidic red soil （Aerisol）. Then one-meter depth soil profiles for each soil were transplanted in 3 stations to build the field experiment. The two-year experimental results （2006-2007） showed soil nitrification intensity （SNI） changed with the temperature and rainfall during the maize tasseling stage. From Hailun to Yingtan, with an increase of monthly average temperature from 22.3℃ to 26.8℃ and the monthly rainfall from 100.8 mm to 199.6 mm, SNI decreased by 64.2%-67.2% for black soil, 52.1%-52.5% for Chao soil, and 41.7%-75.2% for red soil, respectively. There were significant negative correlations between SNI and temperature and rainfall, with a correlation coefficient of r = - 0. 354 （p 〈 0.01 ） and r = - 0.290 （p 〈 0.01 ）, respectively. The total number of soil nitrobacteria and the intensity of soil nitrification was affected by soil types, which increased in a sequence of Chao soil 〉 black soil 〉 red soil. Among soil properties, pH affected SNI significandy, with a correlation coefficient of r = 0.551 （p 〈 0.01）. In generally, climate condition （temperature and rainfall）, soil type and fertilization present an integrated impact on soil nitrification process, and there were significant interactions of climate x soil type, climate x fertilization, soil type × fertilization, and climate × soil type ×fertilization.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2009年第1期206-213,共8页
Environmental Science
基金
中国科学院知识创新工程方向性项目(KZCX2-YW-407)
国家自然科学基金重大项目(30590381)
