施肥模式对雨养旱地温室气体排放的影响

摘要

Based on the measurement of CO2,N2O and CH4 emissions from corn farmland by the static-chamber/gas chromatography technique,this paper studied the effects of two kinds of fertilization modes including traditional fertilization and controlling fertilization on greenhouse gas emissions in rain-fed dry land.The results showed that the seasonal characteristics and total amount of emissions of CO2 and CH4 were not significantly different under various fertilization modes,whereas those of N2O were significantly different between two kinds of fertilization modes.Compared to traditional fertilization,N2O emission from cropland under controlling fertilization decreased by 70.40％,indicating that base fertilizer application was an important factor affecting N2O emission.Integrated evaluation of greenhouse effect showed that,the global warming potential (GWP) and greenhouse gas intensity (GHGI) of controlling fertilization were significantly lower than those of traditional fertilization,which decreased by 73.08％ and 74.00％,respectively.The study further suggested that amendment of N:P ration (controlling fertilization) is an effective approach to reduce greenhouse gases in rain-fed dry land.%采用静态箱/气相色谱法对雨养旱作玉米生长季农田土壤CO2、N2O和CH4的排放通量进行观测,研究了改变氮、磷配比(调控施肥)和传统施肥两种模式对山西雨养旱地温室气体排放的影响.结果表明,施肥模式对土壤CO2、CH4季节排放特征和排放总量影响不明显,但显著影响N2O的季节排放动态特征和排放总量.基肥施用是影响雨养旱地N2O排放的主要因素.与传统施肥相比,调控施肥N2O季节排放总量减少70.40％.CH4和N2O的综合温室效应分析结果表明,调控施肥方式下的全球增温潜势(GWP)与温室气体排放强度(GHGI)均显著低于传统施肥方式,分别降低73.08％和74.00％,本研究进一步表明雨养旱地采用调控施肥的方式是一种较好的温室气体减排措施.