应用生态学报2017，Vol.28Issue(7)：2261-2268,8.DOI:10.13287/j.1001-9332.201707.010
施氮对关中还田玉米秸秆腐解和养分释放特征的影响
Effects of nitrogen application on decomposition and nutrient release of returned maize straw in Guanzhong Plain, Northwest China
摘要
Abstract
With 15N isotope labeled maize straw in nylon net bags and buried in the wheat field at two N rates of 0 and 200 kg N · hm-2,the effects of nitrogen application on the decomposition of straw dry matter and the release dynamics of carbon,nitrogen,phosphorus and potassium (C,N,P and K) after maize straw retention were investigated in the winter wheat-summer maize rotation system in Guanzhong Plain,Shaanxi,China.Results showed that N application did not affect the decomposition of the returned straw C and dry matter,but promoted the release of P and inhibited the release of N and K from straw during sowing to wintering periods of winter wheat.From the grain filling to the harvest of winter wheat,the decomposition of the returned straw and the release of N,P and K were not affected,but the release of straw C was significantly enhanced by N application.The release dynamic of straw C was synchronized with the decomposition of the dry matter,and the C/N of straw declined gradually with the extension of wheat growing.Until the harvest of winter wheat,the accumulative decomposition rate of straw dry matter was less than 50％,and the total straw C release rate was around 47.9％ to 51.1％.The C/N ratio of the returned straw was decreased from 32.2 to 20.2 and 17.9,respectively at N rates of 0 and 200 kg N · hm-2.From sowing to harvest of winter wheat,the net release of N,P and K from the straw was observed.The N release was 7.2-9.4 kg · hm-2 and 12.7％-16.6％ of the total straw N,and the P release was 1.29-1.44 kg · hm-2 and 29.0％-32.4％ of the total straw P,while a great deal of K was released quickly,with approximately 80％ of the straw K released before wintering,51.8-52.5 kg · hm-2 and 90.5％-91.7％ of the total straw K released at wheat harvest.It was suggested that the K fertilizer application should be decreased for the winter wheat due to the great amount K release from the returned maize straw,and an extra amount of N and P fertilizer should be applied under the straw retention cropping system.关键词
冬小麦/轮作/玉米秸秆/碳/氮、磷、钾/腐解Key words
winter wheat/rotation/maize straw/C/N, P, K/decomposition引用本文复制引用
黄婷苗,王朝辉,侯仰毅,顾炽明,李晓,郑险峰..施氮对关中还田玉米秸秆腐解和养分释放特征的影响[J].应用生态学报,2017,28(7):2261-2268,8.基金项目
本文由国家现代农业产业技术体系建设专项(CARS-3-1-31)、国家公益性行业(农业)科研专项(201303104,201503124)、农业科研杰出人才及其创新团队培养计划项目和国家科技支撑计划项目(2015BAD23B04)资助 This work was supported by the China Agricultural Research System (CARS-3-1-31),the Special Fund for Agro-scientific Research in the Public Interest (201303104,201503124),the Agricultural Scientific Research Talent and Team Program,and the National Key Science and Technology Support Program of China (2015BAD23B04). （CARS-3-1-31）
