通过3年定位试验,采用静态箱/气相色谱法对壤质草甸土区玉米生产进行了全生长季N2O排放通量的观测,分析了不同施氮方式对N2O排放总量、排放系数和玉米产量的影响。结果表明:减少氮肥用量20%的缓控释肥处理与秸秆还田配化肥处理产量居高...通过3年定位试验,采用静态箱/气相色谱法对壤质草甸土区玉米生产进行了全生长季N2O排放通量的观测,分析了不同施氮方式对N2O排放总量、排放系数和玉米产量的影响。结果表明:减少氮肥用量20%的缓控释肥处理与秸秆还田配化肥处理产量居高,而且二者间差异不显著;秸秆还田促进了农田土壤N2O排放,使得秸秆还田配化肥处理的年均N2O季节排放总量最高,达到1.50 kg N·hm-2;年均N2O季节排放总量与施肥量之间相关系数达到了0.97;随着试验年限的增加,N2O-N季节排放系数受施肥量的影响逐年增加,相关系数从2009年的-0.015增加到2011年的0.624。因此不同施氮方式对N2O季节排放的影响需要通过多年定位来准确把握,同时在研究农田N2O-N季节排放时要适当考虑植株生长过程中N2O的排放。兼顾产量和减排2个因素,建议推广缓控释肥的减量施用。展开更多
In order to study effects of application of contmllE=d release fertilizer on ni- trous oxide (N2O) emission in slope cultivated land with purple soil, four treatments including the control group (CK), urea (UR),...In order to study effects of application of contmllE=d release fertilizer on ni- trous oxide (N2O) emission in slope cultivated land with purple soil, four treatments including the control group (CK), urea (UR), controlled release nitrogen fertilizer (CR), and controlled release nitrogen fertilizer+urea (25%CR, 75%UR) were set up, and their impacts on maize yield, surface runoff and nitrogen loss in the growth pe- riod of maize and N2O emission were studied. The results show that maize yield, surface runoff, nitrogen loss from subsurface flow, and N2O emission in the control group was far lower than that in the fertilization treatments, revealing that fertilization was the main reason for nitrogen loss and N2O emission. Among the four treat- ments, nitrogen loss from subsurface flow in the treatment CR was the highest, up to 31.7 kg/hm^2, but N2O emission was 0.35 kg/hm^2, which was 37% less than that in the treatment UR. Nitrogen loss from subsurface flow in the treatment 25% CR was the lowest, only 20.9 kg/hm^2, and N2O emission was 15% less than that in the treatment UR. Nitrogen was slowly released from controlled release nitrogen fertilizer in the growth period, and controlled release nitrogen fertilizer could reduce N2O emis- .sion from slope cultivated land due to low content of soil inorganic nitrogen, but it could increase the nitrogen loss from subsurface flow. Therefore, the combination of controlled release fertilizer and urea can not only reduce N2O emission but also de- crease nitrogen loss from subsurface flow.展开更多
Using the closed chamber technique, the in situ measurements of N2O and CH4 fluxes was conducted in a broad-leaved Korean pine mixed forest ecosystem in Changbai Mountain, China. from June 1994 to october 1995. The re...Using the closed chamber technique, the in situ measurements of N2O and CH4 fluxes was conducted in a broad-leaved Korean pine mixed forest ecosystem in Changbai Mountain, China. from June 1994 to october 1995. The relationships between fluxes (N2O and CH4) and some major environmental factors (temperature, soil water content and soil availabIe nitrogen) were studied. A significant positive correlation between Nzo emission and air/soil temperature was observed, but no significant correIation was found between N2O emission and soil water content (SWC). This result showed that temperature was an important controlling factor of N2O flux. There was a significant correlation between CH4 uptake and SWC, but no significant correlation was found between CH4 uptake and temperature. This suggested SWC was an important factor controlling CH4 uptake. The very significant negative correlation between logarithmic N2O flux and soil nitrate concentration, significant negative correlation between CH4 flux and soil ammonium content were also found.展开更多
文摘通过3年定位试验,采用静态箱/气相色谱法对壤质草甸土区玉米生产进行了全生长季N2O排放通量的观测,分析了不同施氮方式对N2O排放总量、排放系数和玉米产量的影响。结果表明:减少氮肥用量20%的缓控释肥处理与秸秆还田配化肥处理产量居高,而且二者间差异不显著;秸秆还田促进了农田土壤N2O排放,使得秸秆还田配化肥处理的年均N2O季节排放总量最高,达到1.50 kg N·hm-2;年均N2O季节排放总量与施肥量之间相关系数达到了0.97;随着试验年限的增加,N2O-N季节排放系数受施肥量的影响逐年增加,相关系数从2009年的-0.015增加到2011年的0.624。因此不同施氮方式对N2O季节排放的影响需要通过多年定位来准确把握,同时在研究农田N2O-N季节排放时要适当考虑植株生长过程中N2O的排放。兼顾产量和减排2个因素,建议推广缓控释肥的减量施用。
基金Supported by Financial Innovation Ability Promotion Project of Sichuan Province,China(2013XXXK-013,2016GYSH-023)National Key Technology R&D Program(2012BAD05B03-8)~~
文摘In order to study effects of application of contmllE=d release fertilizer on ni- trous oxide (N2O) emission in slope cultivated land with purple soil, four treatments including the control group (CK), urea (UR), controlled release nitrogen fertilizer (CR), and controlled release nitrogen fertilizer+urea (25%CR, 75%UR) were set up, and their impacts on maize yield, surface runoff and nitrogen loss in the growth pe- riod of maize and N2O emission were studied. The results show that maize yield, surface runoff, nitrogen loss from subsurface flow, and N2O emission in the control group was far lower than that in the fertilization treatments, revealing that fertilization was the main reason for nitrogen loss and N2O emission. Among the four treat- ments, nitrogen loss from subsurface flow in the treatment CR was the highest, up to 31.7 kg/hm^2, but N2O emission was 0.35 kg/hm^2, which was 37% less than that in the treatment UR. Nitrogen loss from subsurface flow in the treatment 25% CR was the lowest, only 20.9 kg/hm^2, and N2O emission was 15% less than that in the treatment UR. Nitrogen was slowly released from controlled release nitrogen fertilizer in the growth period, and controlled release nitrogen fertilizer could reduce N2O emis- .sion from slope cultivated land due to low content of soil inorganic nitrogen, but it could increase the nitrogen loss from subsurface flow. Therefore, the combination of controlled release fertilizer and urea can not only reduce N2O emission but also de- crease nitrogen loss from subsurface flow.
文摘Using the closed chamber technique, the in situ measurements of N2O and CH4 fluxes was conducted in a broad-leaved Korean pine mixed forest ecosystem in Changbai Mountain, China. from June 1994 to october 1995. The relationships between fluxes (N2O and CH4) and some major environmental factors (temperature, soil water content and soil availabIe nitrogen) were studied. A significant positive correlation between Nzo emission and air/soil temperature was observed, but no significant correIation was found between N2O emission and soil water content (SWC). This result showed that temperature was an important controlling factor of N2O flux. There was a significant correlation between CH4 uptake and SWC, but no significant correlation was found between CH4 uptake and temperature. This suggested SWC was an important factor controlling CH4 uptake. The very significant negative correlation between logarithmic N2O flux and soil nitrate concentration, significant negative correlation between CH4 flux and soil ammonium content were also found.