Many studies have focused on various agricultural management measures to reduce agricultural nitrous oxide (N2O) emission. However, few studies have investigated soil N2O emissions in intercropping systems in the No...Many studies have focused on various agricultural management measures to reduce agricultural nitrous oxide (N2O) emission. However, few studies have investigated soil N2O emissions in intercropping systems in the North China Plain. Thus, we conducted a ifeld experiment to compare N2O emissions under monoculture and maize-legume intercropping systems. In 2010, ifve treatments, including monocultured maize (M), maize-peanut (MP), maize-alfalfa (MA), maize-soybean (MS), and maize-sweet clover (MSC) intercropping were designed to investigate this issue using the static chamber technique. In 2011, M, MP, and MS remained, and monocultured peanuts (P) and soybean (S) were added to the trial. The results showed that total production of N2O from different treatments ranged from (0.87±0.12) to (1.17±0.11) kg ha-1 in 2010, while those ranged from (3.35±0.30) to (9.10±2.09) kg ha-1 in 2011. MA and MSC had no signiifcant effect on soil N2O production compared to that of M (P<0.05). Cumulative N2O emissions from MP in 2010 were signiifcantly lower than those from M, but the result was the opposite in 2011 (P<0.05). MS signiifcantly reduced soil N2O emissions by 25.55 and 48.84%in 2010 and 2011, respectively (P<0.05). Soil N2O emissions were signiifcantly correlated with soil water content, soil temperature, nitriifcation potential, soil NH4+, and soil NO3-content (R2=0.160-0.764, P<0.01). A stepwise linear regression analysis indicated that soil N2O release was mainly controlled by the interaction between soil moisture and soil NO3-content (R2=0.828, P<0.001). These results indicate that MS had a coincident effect on soil N2O lfux and signiifcantly reduced soil N2O production compared to that of M over two growing seasons.展开更多
Plant species of cropping systems may affect nitrous oxide (N2O) emissions. A field experiment was conducted to investigate dynamics of N2O emissions from rice-wheat fields from December 2006 to June 2007 and the re...Plant species of cropping systems may affect nitrous oxide (N2O) emissions. A field experiment was conducted to investigate dynamics of N2O emissions from rice-wheat fields from December 2006 to June 2007 and the relationships of soil and plant parameters with N2O emissions. The results indicated that N2O emissions from different wheat varieties ranged front 12 to 291 Ixg N2O-N m-2 h 1 and seasonal N2O emissions ranged from 312 to 385 mg N2O-N m -2 In the rice season, it was from 11 to 154 μg N2O-N m-2 h-1 with seasonal N2O emission of 190-216 mg N2O-N m-2. The seasonal integrated flux of N2O differed significantly among wheat and rice varieties showed higher seasonal N2O emissions. In the wheat season, N2O The wheat variety HUW 234 and rice variety Joymoti emissions correlated with soil organic carbon (SOC), soil NO3-N, soil temperature, shoot dry weight, and root dry weight. Among the variables assessed, soil temperature followed by SOC and soil NO3-N were considered as the important variables influencing N2O emission. N2O emission in the rice season was significantly correlated with SOC, soil NO3-N, soil temperature, leaf area, shoot dry weight, and root dry weight. The main driving forces influencing N2O emission in the rice season were soil NO3-N, leaf area, and SOC.展开更多
[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, C...[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, CH4 and N2O in soils of farmland were overviewed. [Result] Production and discharge of CO2, CH. and N2O played an important role in circulation of carbon and nitrogen in terrestrial ecosystem and constituted a key method for carbon and nitrogen output. It is significant to conduct research on reduction of greenhouse gas and increase of absorption. [Conclusion] The research is beneficial for exploration on discharge rule and influential factors of greenhouse gases, providing theoretical references for reduction of greenhouse gases and study on climate change.展开更多
基金supported by the National Key Technologies R&D Program of China (2011BAD16B15 and 2012BAD14B03)
文摘Many studies have focused on various agricultural management measures to reduce agricultural nitrous oxide (N2O) emission. However, few studies have investigated soil N2O emissions in intercropping systems in the North China Plain. Thus, we conducted a ifeld experiment to compare N2O emissions under monoculture and maize-legume intercropping systems. In 2010, ifve treatments, including monocultured maize (M), maize-peanut (MP), maize-alfalfa (MA), maize-soybean (MS), and maize-sweet clover (MSC) intercropping were designed to investigate this issue using the static chamber technique. In 2011, M, MP, and MS remained, and monocultured peanuts (P) and soybean (S) were added to the trial. The results showed that total production of N2O from different treatments ranged from (0.87±0.12) to (1.17±0.11) kg ha-1 in 2010, while those ranged from (3.35±0.30) to (9.10±2.09) kg ha-1 in 2011. MA and MSC had no signiifcant effect on soil N2O production compared to that of M (P<0.05). Cumulative N2O emissions from MP in 2010 were signiifcantly lower than those from M, but the result was the opposite in 2011 (P<0.05). MS signiifcantly reduced soil N2O emissions by 25.55 and 48.84%in 2010 and 2011, respectively (P<0.05). Soil N2O emissions were signiifcantly correlated with soil water content, soil temperature, nitriifcation potential, soil NH4+, and soil NO3-content (R2=0.160-0.764, P<0.01). A stepwise linear regression analysis indicated that soil N2O release was mainly controlled by the interaction between soil moisture and soil NO3-content (R2=0.828, P<0.001). These results indicate that MS had a coincident effect on soil N2O lfux and signiifcantly reduced soil N2O production compared to that of M over two growing seasons.
基金Supported by the Department of Science and Technology,Government of India (No. ES/71/07/2003)
文摘Plant species of cropping systems may affect nitrous oxide (N2O) emissions. A field experiment was conducted to investigate dynamics of N2O emissions from rice-wheat fields from December 2006 to June 2007 and the relationships of soil and plant parameters with N2O emissions. The results indicated that N2O emissions from different wheat varieties ranged front 12 to 291 Ixg N2O-N m-2 h 1 and seasonal N2O emissions ranged from 312 to 385 mg N2O-N m -2 In the rice season, it was from 11 to 154 μg N2O-N m-2 h-1 with seasonal N2O emission of 190-216 mg N2O-N m-2. The seasonal integrated flux of N2O differed significantly among wheat and rice varieties showed higher seasonal N2O emissions. In the wheat season, N2O The wheat variety HUW 234 and rice variety Joymoti emissions correlated with soil organic carbon (SOC), soil NO3-N, soil temperature, shoot dry weight, and root dry weight. Among the variables assessed, soil temperature followed by SOC and soil NO3-N were considered as the important variables influencing N2O emission. N2O emission in the rice season was significantly correlated with SOC, soil NO3-N, soil temperature, leaf area, shoot dry weight, and root dry weight. The main driving forces influencing N2O emission in the rice season were soil NO3-N, leaf area, and SOC.
基金Supported by the Special R&D Fund for Public Welfare IndustryApplication of Remote Sensing Technology in Agrometeorological Forecast(GYHY201106027)~~
文摘[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, CH4 and N2O in soils of farmland were overviewed. [Result] Production and discharge of CO2, CH. and N2O played an important role in circulation of carbon and nitrogen in terrestrial ecosystem and constituted a key method for carbon and nitrogen output. It is significant to conduct research on reduction of greenhouse gas and increase of absorption. [Conclusion] The research is beneficial for exploration on discharge rule and influential factors of greenhouse gases, providing theoretical references for reduction of greenhouse gases and study on climate change.