施氮稻田温室气体排放的环境效益评价

基于对成都平原稻田生态系统CO2、CH4和N2O排放的原位观测,应用碳税法、工业制氧成本法和造林成本法对施氮情况下稻田生态系统气体调节的环境效益进行评价。研究表明,施氮情况下,稻田温室气体排放产生的环境负效益增加14.4%,但由于施氮提高了水稻生物量,使稻田生态系统固定CO2和释放O2的环境正效益提高26.2%,因而稻田生态系统通过自身气体调节功能产生的环境效益提高47.8%。所以,施氮通过提高稻田生态系统自身气体调节功能,能够降低大气中温室气体的浓度,抑制温室效应的发生,而水稻在调节稻田气体,减轻温室效应中起到主要作用。

Impact of nitrogen fertilizer on the environmental benefit of greenhouse gases emission in rice paddy ecosystem

Based on the result of field experiment of CO2,CH4 and N2O emission from rice growing season in rice-wheat rotation system in Chengdu plain with static chamber/gas chromatograph techniques,the environmental benefit of gas regulation is investigated with economics methods.The result show as follows： the negative environmental benefit of CO2、CH4 and N2O emission increased 14.4% because of N fertilization in rice paddy,but,the positive benefit of CO2 uptake and O2 emission enhanced 26.2%.So,the total environmental benefit increased 46.7% through gases regulation services in rice paddy ecosystem.Therefore,N fertilization reduces the greenhouse gas density in the atmosphere through strengthening gases regulation services in the rice paddy ecosystem,and the greenhouse effect can be mitigate Rice plays the key role in regulating the gases and reducing the greenhouse effect in rice paddy ecosystem.gas regulation services;environmental benefit;rice paddy ecosystem