基于稻草还田的稻田生态系统N素吸收特性研究  

Nitrogen Uptake by Rice Paddy Ecosystem Based on Rice Straw Incorporation.

作　　者：佘冬立[1] 谢小立[1] 王凯荣[1] 陈敏[2] 

机构地区：[1]中国科学院亚热带农业生态研究所 [2]湖南省桃江县农业局,湖南桃江413400

出　　处：《生态与农村环境学报》2007年第1期88-91,共4页Journal of Ecology and Rural Environment

基　　金：国家重点基础研究发展计划项目(2005CB121106);中国科学院知识创新工程(KZCX3-SW-441);CERN野外台站研究基金

摘　　要：采用田间试验研究了稻草还田环境下施N模式对稻田生态系统N素吸收量及N肥利用率的影响。结果表明：稻草还田配施N肥能显著提高水稻N索吸收转化功能，且高量常规N处理下尽管水稻N索吸收量增多，但只有一定量N素能转移到穗部，其余则仍然留存在营养器官中。所有处理N肥的吸收利用率为26．7％-30．7％、农学利用率为10．5—12．2kg·kg^-1，N肥利用率较低，且随着施N量增加呈下降趋势。随着与稻草配合施用，N肥利用率各指标中除吸收利用率略有下降外，其他各指标（包括农学利用率、生理利用率和偏生产力）均有一定程度提高。根据稻田作物N素吸收转化状况与N肥利用率，在全年稻草还田量为7500kg·hm^-2的红壤稻田系统，建议全年适宜配施N量为185kg·hm^-2。Field studies were conducted to investigate effects of rice straw incorporation and nitrogen application models on process of nitrogen uptake by rice paddy ecosystem and fertilizer-N use efficiency in the double rice cropping system. Results show that rice straw incorporation coupled with N application at a proper rate could increase nitrogen uptake by rice plants and nitrogen cycling in the rice field ecosystem. In the treatment high in N application rate, nitrogen uptake by rice increased, but the amount of N transferred to the ears was limited and the rest still remained in the vegetative organs. N recovery rate, regardless of treatment, ranged between 26.7% and 30.7%, and N agronomic efficiency, between 10.5 and 12.2 kg · kg^-1. Obviously, fertilizer-N use efficiency is low,and it decreased with rising nitrogen application rate. Straw incorporation improved slightly use efficiency of applied N, including N agronomic efficiency, N physiological efficiency, and partial productivity, except for N recovery rate. According to the nitrogen absorption and transformation, the nitrogenous fertilizer use efficiency, and the fact that 7 500 kg · hm^-2 rice straw is incorporated annually, it is recommended that 185 kg ·hm^-2 of N be applied a year in the red earth-paddy system.

关 键 词：稻草还田 稻田生态系统 N紊 吸收 利用率 

分 类 号：S511[农业科学—作物学]