耕作方式及秸秆还田对华北平原土壤全氮及其组分的影响  

Effects of tillage and straw mulching on soil total nitrogen and its components in north China plain

作　　者：濮超 刘鹏 阚正荣 祁剑英 马守田 赵鑫 张海林 Pu Chao;Liu Peng;Kan Zhengrong;Qi Jianying;Ma Shoutian;Zhao Xin;Zhang Hailin(College of Agronomy and Biotechnology, China Agricultural Universit;Key Laboratory of Farming System, Ministry of Agriculture, Beijing 100193, Chin)

机构地区：[1]中国农业大学农学院,农业部农作制度重点实验室,北京100193

出　　处：《农业工程学报》2018年第9期160-166,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：公益性行业(农业)科研专项(201503136)

摘　　要：为明确耕作方式对农田土壤全氮及其组分的影响,该文于中国农业大学吴桥实验站展开研究。田间试验布置于2008年,设置翻耕秸秆不还田(PT),翻耕秸秆还田(PTS),免耕秸秆还田(NTS)和旋耕秸秆还田(RTS)4个处理。于2015年冬小麦收获后取样,测定分析了土壤全氮、颗粒氮、矿物结合态氮含量以及土壤全氮储量。研究结果表明,0~5和5~10 cm土层的土壤全氮含量NTS和RTS显著高于PTS,但10~20和20~30 cm土层显著降低(P<0.05)。0~50 cm土层的土壤全氮储量秸秆还田各处理间差异不显著,但NTS和PTS较PT分别提高了7.78%和11.09%(P<0.05)。在土壤全氮及其组分中,土壤颗粒氮对耕作方式表现出最高的敏感性。0~5 cm土层的土壤颗粒氮含量及其在土壤全氮中的占比NTS和RTS均高于PTS,但在20~30 cm土层均低于PTS(P<0.05)。与PT相比,PTS仅提高了0~20 cm土层的土壤全氮和颗粒氮含量,而土壤矿物结合态氮含量没有显著差异,NTS和RTS则同步提高了0~10 cm土层的土壤全氮、颗粒氮及矿物结合态氮含量(P<0.05)。综上所述,免耕和旋耕提高了土壤全氮及其组分在表层土壤中的分布,翻耕则在较深土层更具优势,但翻耕阻碍了耕层土壤矿物结合态氮的积累,增加了氮素损失风险。Growing concerns about environmental conservation and sustainable intensification have raised interests in enhancing soil nitrogen pools. To estimate the effects of different tillage systems on soil nitrogen pools, a field experiment initiated from 2008 with 4 tillage systems（plow tillage without residue retention, PT; plow tillage with residue retention, PTS; no-till with residue retention, NTS; rotary tillage with residue retention, RTS） was conducted in a winter wheat-summer maize double cropping system at China Agricultural Experimental Station in Wuqiao on the North China Plain（NCP）. After 7 years of experiment, soil total nitrogen（TN）, particulate organic matter nitrogen（POM-N） and mineral-associated organic matter nitrogen（MAOM-N） were determined from 5 soil depths increments. This study observed that concentrations of TN under NTS and RTS were significantly higher than that under PTS in the 0-5 and 5-10 cm soil layers（25.05% and 23.39% higher in the 0-5 cm layer, and 8.16% and 19.60% higher in the 5-10 cm layer, respectively）, but trends reversed in the 10-20 and 20-30 cm soil layers（7.72% and 6.66% lower in the 10-20 cm layer, and 26.76% and 27.20% lower in the 20-30 cm layer, respectively）. Furthermore, no significant differences in total nitrogen stocks of either 0-30 or 0-50 cm soil layer were observed among tillage treatments with residue retention, but all of them were higher than that of PT treatment. POM-N showed the highest sensitivity among soil total nitrogen and its fractions. Concentration of POM-N under NTS increased by 51.79% in the 0-5 cm topsoil when compared with PTS, but decreased by 18.35% and 53.11% in the 10-20 and 20-30 cm subsoils, respectively. The proportion of POM-N in TN under NTS was also higher than that under PTS in the 0-5 cm layer, but lower in the 5-10 and 20-30 cm layers. Similarly, RTS increased both POM-N concentration and the proportion of POM-N in TN in the 0-5 cm layer when compared with PTS, but decreased the two in the 20-30 cm layer. H

关 键 词：土壤 氮 秸秆 免耕 保护性耕作 全氮储量 颗粒氮 矿物结合态氮 

分 类 号：S34[农业科学—作物栽培与耕作技术]