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Long-term manure amendment enhances N_(2)O emissions from acidic soil by alleviating acidification and increasing nitrogen mineralization
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作者 Lei Wu Jing Hu +4 位作者 Muhammad Shaaban Jun Wang Kailou Liu Minggang Xu Wenju Zhang 《Journal of Integrative Agriculture》 2026年第1期262-272,共11页
Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse... Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse gas N_(2)O emissions from acidic soil mediated by long-term manure application remain poorly understood. Herein, we investigated N_(2)O emission and its linkage with gross N mineralization and nitrification rates, as well as nitrifying and denitrifying microbes in an acidic upland soil subjected to 36-year fertilization treatments, including an unfertilized control(CK), inorganic fertilizer(F), 2× rate of inorganic fertilizer(2F), manure(M), and the combination of inorganic fertilizer and manure(FM) treatments. Compared to the CK treatment(1.34 μg N kg^(-1) d^(-1)), fertilization strongly increased N_(2)O emissions by 34-fold on average, with more pronounced increases in the manure-amendment(10.6-169 μg N kg^(-1) d^(-1)) than those in the inorganic fertilizer treatments(3.26-5.51 μg N kg^(-1) d^(-1)). The manure amendment-stimulated N_(2)O emissions were highly associated with increased soil pH, mean weight diameter of soil aggregates, substrate availability(e.g., particulate organic carbon, NO_(3)^(-)and available phosphorus), gross N mineralization rates, denitrifier abundances and the(nirK+nirS)/nosZ ratio. These findings suggest that the increased N_(2)O emissions primarily resulted from alleviated acidification, increased substrate availability and improved soil structure, thus enhancing microbial N mineralization and favoring N_(2)O^(-)producing denitrifiers over N_(2)O consumers. Moreover, ammonia-oxidizing bacteria(AOB) rather than ammonia-oxidizing archaea(AOA) positively correlated with soil NO_(3)^(-)concentration and N_(2)O emissions, indicating that nitrification indirectly contributed to N_(2)O production by supplying NO_(3)^(-)for denitrification. Collectively, manure amendment potentially stimulates N_(2)O emissions, primarily resulting from alleviated soil acidification and increased substrate availability, thus enhancing N mineralization and denitrifier-mediated N_(2)O production. Our findings suggest that consideration should be given to the greenhouse gas budgets of agricultural ecosystems when applying manure for managing the pH and fertility of acidic soils. 展开更多
关键词 long-term manure amendment N_(2)o emission nitrogen mineralization denitrification (nirK+nirS)/nosZ
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Effect of Measurement Time on Emission Flux of CO_2 and N_2O in Black Soil Region
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作者 乔云发 韩晓增 赵兰坡 《Agricultural Science & Technology》 CAS 2012年第2期361-364,共4页
[Objective] The aim was to investigate and reveal effect of measurement time on emission flux of CO2 and N2O to ensure the optimum time of emission flux, in order to provide scientific reference for emission reduction... [Objective] The aim was to investigate and reveal effect of measurement time on emission flux of CO2 and N2O to ensure the optimum time of emission flux, in order to provide scientific reference for emission reduction of greenhouse gas in black soil region. [Method] Based on experiment of long-term fertilizer location in black soil region, the paper studied on daily dynamic variation of CO2 and N2O discharge in 3 key growth periods (booting stage, grain-filling stage and mature stage) to reveal differences of CO2 and N2O emission flux in different times. [Result] Daily variations of CO2 and N2O emission flux were large, from 205 mg/(m2·h) to 552 mg/(m2·h) for CO2 and from 51 h to 295 μg/(m2·h) for N2O. Trend of CO2 discharge in different growth times showed a unimodal curve, and the peak was at noon of 12:00 and the peak valley was at 3:00 am; discharge of N2O was small in day time at booting stage and large at night. Regardless of rice growth period effect on CO2 and N2O emission flux, representative time of CO2 discharge was 6:00-8:00 or 16:00-21:00; and time of N2O was 8:00-10:00 or 16:00-21:00; if CO2 and N2O emission fluxes were measured simultaneously, the optimum time was 16:00-18:00; if the measurement was started during 9:00-12:00, correction coefficients of CO2 and N2O were 0.81 and 0.90, respectively. [Conclusion] The result provided scientific reference for reduction of greenhouse gas emission in black soil region. 展开更多
关键词 co2 n2o Black soil Measurement time
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Dynamics of urban carbon emissions:A comparative analysis of pre-and post-lockdown through eddy covariance measurements
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作者 Lu Zhao Hongxing Zhang +4 位作者 Xu Sun Binbin Huang Fei Lu Xiaoke Wang Zhiyun Ouyang 《Journal of Environmental Sciences》 2025年第12期735-747,共13页
Urban areas are the major anthropogenic source of atmospheric CO_(2),thus making longterm and continuous observations of their carbon emission dynamics extremely important.The COVID-19 lockdown served as a natural exp... Urban areas are the major anthropogenic source of atmospheric CO_(2),thus making longterm and continuous observations of their carbon emission dynamics extremely important.The COVID-19 lockdown served as a natural experiment that provided a unique opportunity to analyse the contribution of human activities to CO_(2) emissions from urban areas.In 2020,Beijing experienced COVID-19 confinement with different levels of restrictions on social mobility and economic activity,resulting in reductions in CO_(2) emissions.To investigate the response mechanisms of CO_(2) flux to restriction measures,we analysed CO_(2) flux data obtained using the eddy covariance technique from 2015 to 2020,and compared CO_(2) flux during the COVID-19 confinement period in 2020 with the preceding years(2015-2019)and across various levels of confinement.The results showed that:(1)the annual CO_(2) flux was 2.1±0.2 kg C/(m^(2)·yr)in 2020,which showed a significant reduction of 31.8%compared to the adjacent 2019;(2)the reduction in CO_(2) flux was closely related to the level of restrictions on human activities;(3)most reductions occurred during the morning(85.7%)and evening(32.7%)peak traffic times,indicating that commuting-related transportation is a primary contributor to urban CO_(2) emissions.It is suggested that measures that reduce transportation-related CO_(2) sources should be considered as priorities for reducing urban CO_(2) emissions.The dynamic variation of urban CO_(2) flux captured by the eddy covariance technology is conductive to strengthening the supervision of the implementation of urban carbon emission reduction policies,promoting the achievement of dual carbon goals. 展开更多
关键词 Co_(2)flux Urban carbon emissions CoVID-19 Eddy covariance
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Short-term P addition may improve the stimulating effects of N deposition on N_(2)O emissions in alpine grasslands on the Qinghai-Tibetan Plateau
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作者 Jiannan Xiao Shikui Dong +7 位作者 Hao Shen Ran Zhang Hang Shi Fencai He Wei Li Xiaoyan Li YuLi Chengxiang Ding 《Journal of Integrative Agriculture》 2025年第3期900-912,共13页
The response of N_(2)O emissions to nitrogen(N)addition is usually positive,but its response to phosphorus(P)addition varies,and the underlying mechanisms for the changes in N_(2)O emissions remain unclear.We conducte... The response of N_(2)O emissions to nitrogen(N)addition is usually positive,but its response to phosphorus(P)addition varies,and the underlying mechanisms for the changes in N_(2)O emissions remain unclear.We conducted field studies to examine the response of N_(2)O emissions to N and P addition over two years in three typical alpine grasslands,alpine meadow(AM),alpine steppe(AS),and alpine cultivated grassland(CG)on the Qinghai-Tibet Plateau(QTP).Our results showed consistent increases in N_(2)O emissions under N addition alone or with P addition,and insignificant change in N_(2)O emissions under P addition alone in all three grasslands.N addition increased N_(2)O emissions directly in AM,by lowering soil pH in AS,and by lowering abundance of denitrification genes in CG.N and P co-addition increased N_(2)O emissions in AM and AS but only showed an interactive effect in AM.P addition enhanced the increase in N_(2)O emissions caused by N addition mainly by promoting plant growth in AM.Overall,our results illustrate that short-term P addition cannot alleviate the stimulation of N_(2)O emissions by N deposition in alpine grassland ecosystems,and may even further stimulate N_(2)O emissions. 展开更多
关键词 Tibetan alpine grassland N_(2)o emissions nitrogen phosphorus N-cycling functional gene
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Color tunable emission and scintillation properties of Eu-doped lanthanum alumino-silicate glasses
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作者 Yuanwei Zhu Gao Tang +14 位作者 Zhehao Hua Laishun Qin Hang Yin Qinhua Wei Sen Qian Jing Ren Xin-Yuan Sun Danping Chen Minghui Zhang Jifeng Han Hua Cai Shan Liu Weichang Li Dong Yang Jinsheng Jia 《Journal of Rare Earths》 2025年第11期2385-2394,I0003,共11页
A series of Eu^(2+)/Eu^(3+)doped 20La_(2)O_(3)-20Al_(2)O_(3)-60SiO_(2)glasses(LAS:Eu)were fabricated via melting quenching method in air atmosphere.By introducing the reducing agent Si_(3)N_(4),the ratio of Eu^(2+)/Eu... A series of Eu^(2+)/Eu^(3+)doped 20La_(2)O_(3)-20Al_(2)O_(3)-60SiO_(2)glasses(LAS:Eu)were fabricated via melting quenching method in air atmosphere.By introducing the reducing agent Si_(3)N_(4),the ratio of Eu^(2+)/Eu^(3+)in glasses can be controlled under atmospheric conditions at 1520℃for 5 h.As the tunable Eu^(2+)/Eu^(3+)component in LAS:Eu glasses,the wavelength conversion of photoluminescence is achieved upon the395 nm excitation,where LAS:0.7Eu exhibits a color coordinate of(0.334,0.314).According to calculation,the energy transfer mechanism between Eu^(2+)and Eu^(3+)in glasses is dipole-dipole interactions dominate.Meanwhile,relative X-ray excited luminescence(XEL)intensity of the single Eu^(2+)doped glass can reach 38.6%of that of Bi_(4)Ge_(3)O_(12)(BGO)crystal.The temperature-dependent emission spectra of the LAS:Eu glasses were tested under photoluminescence and X-ray excitation,and the thermal activation energy was calculated.These results demonstrate the potential of LAS:Eu glass for applications as lightemitting diode(LED)materials and scintillators in nuclear radiation detection. 展开更多
关键词 Eu^(2+)/Eu^(3+)doped Si3N4 reducing aent Energy transfer White light emission Scintillation Rare earths
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Gross nitrogen transformations and N2O emission sources in sandy loam and silt loam soils 被引量:5
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作者 LANG Man LI Ping WEI Wei 《Journal of Arid Land》 SCIE CSCD 2021年第5期487-499,共13页
The soil type is a key factor influencing N(nitrogen)cycling in soil;however,gross N transformations and N_(2)O emission sources are still poorly understood.In this study,a laboratory 15N tracing experiment was carrie... The soil type is a key factor influencing N(nitrogen)cycling in soil;however,gross N transformations and N_(2)O emission sources are still poorly understood.In this study,a laboratory 15N tracing experiment was carried out at 60%WHC(water holding capacity)and 25℃to evaluate the gross N transformation rates and N_(2)O emission pathways in sandy loam and silt loam soils in a semi-arid region of Heilongjiang Province,China.The results showed that the gross rates of N mineralization,immobilization,and nitrification were 3.60,1.90,and 5.63 mg N/(kg·d)in silt loam soil,respectively,which were 3.62,4.26,and 3.13 times those in sandy loam soil,respectively.The ratios of the gross nitrification rate to the ammonium immobilization rate(n/ia)in sandy loam soil and silt loam soil were all higher than 1.00,whereas the n/ia in sandy loam soil(4.36)was significantly higher than that in silt loam soil(3.08).This result indicated that the ability of sandy loam soil to release and conserve the available N was relatively poor in comparison with silt loam soil,and the relatively strong nitrification rate compared to the immobilization rate may lead to N loss through NO_(3)–leaching.Under aerobic conditions,both nitrification and denitrification made contributions to N_(2)O emissions.Nitrification was the dominant pathway leading to N_(2)O production in soils and was responsible for 82.0%of the total emitted N_(2)O in sandy loam soil,which was significantly higher than that in silt loam soil(71.7%).However,the average contribution of denitrification to total N_(2)O production in sandy loam soil was 17.9%,which was significantly lower than that in silt loam soil(28.3%).These results are valuable for developing reasonable fertilization management and proposing effective greenhouse gas mitigation strategies in different soil types in semiarid regions. 展开更多
关键词 gross N transformation rates 15N tracing n2o emission sources sandy loam silt loam semi-arid region
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Robustness of anammox granular sludge treating low-strength sewage under various shock loadings:Microbial mechanism and little N2O emission 被引量:4
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作者 Shanyun Wang Guibing Zhu +3 位作者 Yifei Li Xiaoxia Wang Jiemin Zhou Yongzhen Peng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第12期141-153,共13页
With the increasing application of anammox for the treatment of high-strength industrial wastewater,application of anammox in municipal sewage has been gaining more attention.Sludge granulation in particular enhances ... With the increasing application of anammox for the treatment of high-strength industrial wastewater,application of anammox in municipal sewage has been gaining more attention.Sludge granulation in particular enhances the enrichment and retention of anammox bacteria in municipal sewage treatment systems.However,the performance of granular sludge under continuous and varying hydraulic loading shock remains little understood.In this study,the robustness of anammox granular sludge in treating lowstrength municipal sewage under various shock loadings was investigated.Results showed that an upflow anaerobic sludge blanket(UASB)reactor with anammox granules performed well,with anammox specific activity up to 0.28 kg N/kg VSS/day and anti-loading shock capability up to 187.2 L/day during the 8-month testing period.The accumulation rate of N2O(<0.01 kg N/kg VSS/day)in the liquid phase was seven times higher than that of the gas phase,which could be mainly attributed to the incomplete denitrification and insufficient carbon source.However,only a small part of the produced N2O escaped into the atmosphere.High-throughput sequencing and molecular ecological network analyses also identified the bacterial diversity and community structure,indicating the potential resistance against loading shock.The composition and structural analyses showed that polysaccharides were an important functional component in the tightly bound extracellular polymeric substances(TB-EPS),which was the major EPS layer of anammox granules.Scanning electron microscopy(SEM)also showed that the gaps in between the anammoxclusters in the granules inhibit the flotation of the sludge and ensure efficient settling and retention of anammox granules. 展开更多
关键词 ANAMMoX Low-strength sewage Varying shock loadings Microbial mechanism n2o emission
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Effects of Water Regime and Straw Application in Paddy Rice Season on N2O Emission from Following Wheat Growing Season 被引量:2
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作者 ZOUJian-wen HUANGYao +2 位作者 ZONGLiang-gang JIANGJing-yan ZHENGXun-hua 《Agricultural Sciences in China》 CAS CSCD 2003年第1期68-74,共7页
A split-plot experiment in a rice-winter wheat rotation system was performed to study the effects of water regime and wheat straw application in rice-growing season on N2O emission from following wheat growing season.... A split-plot experiment in a rice-winter wheat rotation system was performed to study the effects of water regime and wheat straw application in rice-growing season on N2O emission from following wheat growing season. Water regime in the rice-growing season was designed as the conventional irrigation (flooding/drainage cycle) and the permanent flooding. Wheat straw was incorporated with three rates of 0, 225 and 450 g m-2 into the paddy soil for each water regime just before rice was transplanted. N2O emission was measured by static chamber-gas chromatograph method. Results from the variance analysis indicated that the permanent flooding in rice-growing season markedly enhanced N2O emission in following wheat growing season (P=0. 003), and that the effect of straw application on N2O emission was distinguished between two water regimes. Under the conventional irrigation, incoporation of wheat straw reduced N2O emission in the following wheat growing season, while there were no significant differences in the emission for the straw application rates of 225 and 450 g m-2. No significant differences in N2O emissions were observed among the three rates of straw application for the permanent flooding regime. In addition, the seasonal variation of N2O emission was regulated by soil temperature and moisture. The daily N2O flux (Y, mg m-2 d-1) can be quantitatively described by soil temperature (T, ℃) and moisture (W, WFPS %) asY=A0+A1T+A2W+A3W2(n=23, R2 ≥0. 4159** )or y=C0+C1W+C2W2(n=23,R2≥0. 4074** ). Compared with the effect of soil temperature on N2O emission, soil moisture was an important factor regulating the seasonal pattern of N2O emission. 展开更多
关键词 WINTER-WHEAT n2o emission fluxes Water regime Straw application
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Managed grassland alters soil N dynamics and N2O emissions in temperate steppe 被引量:2
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作者 Lijun Xu Xingliang Xu +7 位作者 Xuejuan Tang Xiaoping Xin Liming Ye Guixia Yang Huajun Tang Shijie Lv Dawei Xu Zhao Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期20-30,共11页
Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen(N) dynamics and nitrous oxide(N2O) emissions. However, it ... Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen(N) dynamics and nitrous oxide(N2O) emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N2O emissions by field experiments in Hulunber in northern China. Soil(0-10 cm), nitrate(NO3-),ammonium(NH4+), and microbial N were measured in plots in a temperate steppe(Leymus chinensis grassland) and two managed grasslands(Medicago sativa and Bromus inermis grasslands) in 2011 and 2012. The results showed conversion of L. chinensis grassland to M.sativa or B. inermis grasslands decreased concentrations of NO3--N, but did not change NH4-N . Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M.sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa(i.e., a legume grass) increased N2O emissions by 26.2%, while the conversion to the B. inermis(i.e., a non-legume grass) reduced N2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO3-+-N and NH4-N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N2O emissions. 展开更多
关键词 Temperate steppe Managed grassland Land use Nitrogen mobility n2o emissions
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The Spatial and Temporal Variation Characteristics of CH<sub>4</sub>and CO<sub>2</sub>Emission Flux under Different Land Use Types in the Yellow River Delta Wetland 被引量:1
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作者 Qingfeng Chen Junjian Ma +1 位作者 Changsheng Zhao Rongbin Li 《Journal of Geoscience and Environment Protection》 2015年第6期26-32,共7页
The Yellow River Delta Wetland is one of the youngest wetlands, and also the most complete, extensive wetlands in China. The wetland in this delta is ecologically important due to their hydrologic attributes and their... The Yellow River Delta Wetland is one of the youngest wetlands, and also the most complete, extensive wetlands in China. The wetland in this delta is ecologically important due to their hydrologic attributes and their roles as ecotones between terrestrial and aquatic ecosystems. In the study, the spatial and temporal variation characteristics of CH4 and CO2 emission flux under five kinds of land use types in the wetland were investigated. The results indicated that the greenhouse gas emission flux, especially the CO2 and CH4, showed distinctly spatial and temporal variation under different land use types in the wetland. In the spring, the emission flux of CO2 was higher than that of CO2 in the autumn, and appeared negative in HW3 and HW4 in the autumn. CH4 emission flux of HW4 and HW5 was negative in the spring and autumn, which indicated that the CH4 emission process was net absorption. Among the five kinds of land use types, the CO2 emission flux of HW4 discharged the largest emission flux reaching 29.3 mg.m-2.h-1, but the CH4 emission flux of HW2 discharged the largest emission flux reaching 0.15 mg.m-2.h-1. From the estuary to the inland, the emission flux of CO2 was decreased at first and then appeared increasing trend, but the emission flux of CH4 was contrary to CO2. 展开更多
关键词 WETLand CH4 and co2 emission flux Land Use Spatial and Temporal Variation
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Effects of temperature change and tree species composition on N20 and NO emissions in acidic forest soils of subtropical China 被引量:2
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作者 Yi Cheng Jing Wang +2 位作者 Shenqiang Wang Zucong Cai Lei Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第3期617-625,共9页
Tree species and temperature change arising from seasonal variation or global warming are two important factors influencing N2O and NO emissions from forest soils. However, few studies have examined the effects of tem... Tree species and temperature change arising from seasonal variation or global warming are two important factors influencing N2O and NO emissions from forest soils. However, few studies have examined the effects of temperatures (5-35℃) on the emissions of forest soil N2O and NO in typical subtropical region. A short-term laboratory experiment was carried out to investigate the influence of temperature changes (5-35℃) on soil N2O and NO emissions under aerobic conditions in two contrasting (broad-leaved and coniferous) subtropical acidic forest types in China. The results showed that the temporal pattern of N2O and NO emissions between the three lower temperatures (5℃, 15℃, and 25℃) and 35℃ was significantly different for both broad-leaved and coniferous forest soils. The effects of temperature on soil N2O and NO emission rates varied between broad-leaved and coniferous forest soils. Both N2O and NO emissions increased exponentially with an increase in temperature in the broad-leaved forest soil. However, N2O and NO emissions in the coniferous forest soil were not sensitive to temperature change between 5℃ and 25℃. N2O and NO emission rates were significantly higher in the broad-leaved forest soil as compared with the coniferous forest soil at all incubation temperatures except 5℃. These results suggest that the broad-leaved forest could contribute more N2O and NO emissions than the coniferous forest for most of the year in the subtropical region of China. 展开更多
关键词 n2o No temperature broad-leaved forest coniferous forest
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Correlations between Mineral Nitrogen Contents and Vertical Distribution of N20 Emission Potentials in Tropical Peat Soils Transformed into Oil Palm Plantations in Sarawak, Malaysia
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作者 Sharon Yu Ling Lau Yasuyuki Hashidoko +2 位作者 Naoki Takahashi Ryusuke Hatano Lulie Melling 《Journal of Agricultural Science and Technology(B)》 2014年第9期691-700,共10页
Tropical peat swamp forest beds that have been reclaimed for agricultural use are generally an active source of nitrous oxide (N2O) efflux, however, the mechanism by which reclaimed tropical peat soils promote the e... Tropical peat swamp forest beds that have been reclaimed for agricultural use are generally an active source of nitrous oxide (N2O) efflux, however, the mechanism by which reclaimed tropical peat soils promote the emergence of N2O emitters in soil microbial communities remains unclear. The purpose of this study was to reveal the vertical distribution of N2O emission potential and its correlation with mineral nitrogen contents in reclaimed soils. Using a culture-based N2O emission assay, the N2O emission potentials of soil at various depths (0-450 cm) were investigated in two oil palm plantations in Sarawak, Malaysia, which had elapsed times of two years (E2Y) and 10 years (El 0Y) after deforestation, respectively. On the basis of the relationship between the vertical profiles of N2O emission potentials and the contents of mineralized nitrogen in the peat soils at various depths, the impact of land management on soil microbial communities was discussed. The peat soil at plantation site E2Y showed a trend of high N2O production in deep layers (200-400 cm), whereas the older plantation site E10Y showed considerably more active N2O emission in shallow soil (10-50 cm). N2O emission potentials among the soil microbial communities at different soil depths at the E10Y site showed positive correlations with NO3- and NH4+ contents, whereas, soils obtained from the E2Y site had N2O emission potentials that were inversely proportional to the contents of NO3-. This contrasting vertical correlation between N2O-emitting potentials and mineralized nitrogen contents in bulk soils suggests that active N2O emission in deep soil at the E2Y site has maintained the original carbon-nitrogen (C/N) ratio of the peat soil, whereas at EIOY, such a regulatory system has been lost due to advanced soil degradation, leading to dynamic changes in the nitrogen cycle in shallow soil. 展开更多
关键词 n2o emitters tropical peat soil vertical n20 emission potential C/N ratio oil palm plantation.
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铵态氮源和碳源对土壤N2O、CO2释放的影响 被引量:9
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作者 王琳 周晓丽 +3 位作者 马银丽 巨晓棠 吉艳芝 张丽娟 《农业资源与环境学报》 CAS 2016年第1期23-28,共6页
在田间持水量WFPS为70%、温度为20℃的条件下,通过室内静态培养方法研究铵态氮源与不同碳源结合,对华北平原典型小麦-玉米轮作体系土壤N_2O、CO_2释放的影响。其中,碳源种类分别为葡萄糖、果胶、淀粉、纤维素、木质素和秸秆。结果表明... 在田间持水量WFPS为70%、温度为20℃的条件下,通过室内静态培养方法研究铵态氮源与不同碳源结合,对华北平原典型小麦-玉米轮作体系土壤N_2O、CO_2释放的影响。其中,碳源种类分别为葡萄糖、果胶、淀粉、纤维素、木质素和秸秆。结果表明添加葡萄糖和果胶有效促进了土壤N_2O的释放,并在第1 d达到最大值,分别为4 039.85μg N_2O-N·kg^(-1)·d^(-1)和2 533.44μg N_2O-N·kg^(-1)·d^(-1);添加纤维素和只施秸秆处理降低了N_2O释放。施入碳源增加了CO_2释放,顺序为纤维素>淀粉>葡萄糖>果胶>秸秆>木质素。培养结束后土壤中铵态氮几乎消耗完全,除添加葡萄糖处理外,其他施碳土壤的硝态氮含量均有所增加。在培养前3d,土壤NH^+_4和NO^-_3总含量与N_2O释放量显著相关。 展开更多
关键词 华北地区 铵态氮源 碳源 n2o co2
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华北平原典型农田CO2和N2O排放通量及其与土壤养分动态和施肥的关系 被引量:13
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作者 叶丹丹 谢立勇 +1 位作者 郭李萍 高霁 《中国土壤与肥料》 CAS CSCD 北大核心 2011年第3期15-20,共6页
对华北平原小麦-棉花(麦棉)、小麦-大豆(麦豆)、小麦-玉米(麦玉)轮作田的CO2和N2O排放通量进行了测定,分析了温室气体排放通量与土壤中碳、氮元素、气温以及施肥等之间的关系。主要结论:1)麦棉、麦豆、麦玉田的土壤CO2平均排放通量分别... 对华北平原小麦-棉花(麦棉)、小麦-大豆(麦豆)、小麦-玉米(麦玉)轮作田的CO2和N2O排放通量进行了测定,分析了温室气体排放通量与土壤中碳、氮元素、气温以及施肥等之间的关系。主要结论:1)麦棉、麦豆、麦玉田的土壤CO2平均排放通量分别为CO2-C 141.7、109.8、128.2 mg.m-2.h-1,其中夏播作物的排放通量高于小麦季;2)麦棉、麦豆及麦玉田作物生长季的土壤N2O平均排放通量分别为N2O-N 98.8、38.9、44.7μg.m-2.h-1,也表现为麦后季作物的排放量高于小麦季;3)同一生育期中不同处理的N2O排放主要与土壤中无机氮含量相关,不同生育期的N2O排放通量主要受不同生育期的土壤温度及水分状况的影响;4)在施肥灌溉后的9 d内土壤N2O排放通量较高,之后逐渐降低,至施肥后22~27 d即与不施肥处理的排放持平。 展开更多
关键词 co2排放通量 n2o排放通量 华北平原 典型农田 轮作制度
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Fluxes of soil carbon dioxide,nitrous oxide and firedamp in broad-leaved/Korean pine forest 被引量:3
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作者 肖冬梅 王淼 +2 位作者 王跃思 姬兰柱 韩世杰 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期107-112,i001,i002,共8页
To understand influence of litters on the emission/absorption of CO2, N2O and CH4 in broadleaved/Korean pine forest in Changbai Mountain, fluxes of soil CO2, N2O and CH4 were measured by closed static chamber techniqu... To understand influence of litters on the emission/absorption of CO2, N2O and CH4 in broadleaved/Korean pine forest in Changbai Mountain, fluxes of soil CO2, N2O and CH4 were measured by closed static chamber technique, from Sept 3, 2002 to Oct 30, 2003 in two types of soil ecosystems, of which one was covered with litters on the surface soil, and the other had no litters. The results showed that litters had significant influences on CO2, N2O and CH4 fluxes (p<0.05). Their diurnal change patterns of plot with litters and litter-free plot were similar, and they all showed emission/absorption peak at 18:00. The diurnal change fluxes of CO2 and N2O of plot with litters were significantly higher than those of the litter-free plot, while the diurnal flux of CH4 of plot with litters was lower than that of litter-free plot. The fluxes of CO2, N2O, and CH4 showed the similar seasonal patternsfor both plots. The fluxes of CO2, CH4 showed their peak fluxes in June, but the fluxes of N2O showed its peak emissions in August. The annual fluxes of CO2 and N2O of plot with litters were significantly higher than those of the litter-free plot, while the annual flux of CH4 of plot with litters was lower than that of litter-free plot. Keywords Flux - CO2, N2O and CH4 - Seasonal variation - Diurnal variation CLC number S718.5 Document code A Foundation item: The study was supported by innovation research project of Institute of Appiied Ecology, Chinese Academy of Sciences (SCXZD0101-02) and National Natural Science Foundation of China (30271068)Bigraphy: XIAO Dong-mei (1979-), female, master of Institute of Applied Ecology. Chinese Academy of Sciences, Shenyang 110016. P. R. China.Responsible editor: Song Funan 展开更多
关键词 flux co2 n2o and CH4 Seasonal variation Diurnal variation
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新疆古尔班通古特沙漠土壤N2O、CH4和CO2通量及其对氮沉降增加的响应 被引量:5
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作者 周晓兵 张元明 +1 位作者 陶冶 吴林 《植物生态学报》 CAS CSCD 北大核心 2017年第3期290-300,共11页
沙漠土壤在全球土壤主要温室气体通量中扮演着重要角色,但是在环境变化条件下的通量估算结果存在很大的不确定性。在新疆古尔班通古特沙漠设定N0、N0.5、N1、N3、N6和N24 6个样方,以0、0.5、1.0、3.0、6.0和24.0 g·m^(–2)·a^... 沙漠土壤在全球土壤主要温室气体通量中扮演着重要角色,但是在环境变化条件下的通量估算结果存在很大的不确定性。在新疆古尔班通古特沙漠设定N0、N0.5、N1、N3、N6和N24 6个样方,以0、0.5、1.0、3.0、6.0和24.0 g·m^(–2)·a^(–1) 6个不同模拟氮(N)沉降浓度进行N处理,两年后开始对施N样方进行为期两个生长季的N_2O、CH_4和CO_2通量测定。研究表明生长季对照样方(N0)的N_2O、CH_4和CO_2的平均通量分别为4.8μg·m^(–2)·h^(–1)、–30.5μg·m^(–2)·h^(–1)和46.7 mg·m^(–2)·h^(–1),季节变化显著影响3种气体的通量。N0、N0.5和N1在春季和夏季具有相似的N_2O排放速率,排放速率高于秋季,而N6和N24的N_2O排放主要受N输入时间影响;CH_4的吸收在春季和夏季相对较高,秋季较低;CO_2的排放量在第一年春季和夏季之间变化较小,但高于秋季排放量,第二年CO_2动态与N浓度相关。N增加通常能显著促进N_2O的排放,但受测定季节和年度的影响,且各处理的N_2O排放因子大小无明显规律;CH_4的吸收受N增加影响不显著;CO_2的排放在第一年不受N增加的影响,第二年高浓度N增加对春季和夏季CO_2排放具有限制作用,对秋季影响不显著。结构方程模型的研究表明,对N_2O、CH_4和CO_2的动态变化影响较大的因子分别是施N浓度、土壤温度或土壤含水量和植株密度。整个生长季由N带来的净通量和增温潜力非常小。 展开更多
关键词 氮沉降 n2o CH4 co2 生物量 结构方程模型
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大气CO2浓度升高和秸秆还田对稻麦轮作农田N2O排放的影响 被引量:9
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作者 董海波 郑循华 +3 位作者 黄耀 姚志生 梅宝玲 朱建国 《气候与环境研究》 CSCD 北大核心 2009年第1期1-8,共8页
随着大气CO2浓度的逐渐升高,CO2的施肥效应很可能对陆地生态系统的N2O地气交换过程产生一定的影响。在江苏北部的中国稻麦轮作FACE(Free-Air Carbon Dioxide Enrichment)实验平台上,采用静态箱暗箱-色谱法,研究了一个稻麦轮作周期(2005... 随着大气CO2浓度的逐渐升高,CO2的施肥效应很可能对陆地生态系统的N2O地气交换过程产生一定的影响。在江苏北部的中国稻麦轮作FACE(Free-Air Carbon Dioxide Enrichment)实验平台上,采用静态箱暗箱-色谱法,研究了一个稻麦轮作周期(2005年6月中旬至2006年6月中旬)3种小麦秸秆还田水平处理(全还田、半还田和不还田)和CO2浓度升高200μmol·mol-1对稻麦轮作农田N2O排放的影响。结果表明,就当地传统农田管理方式下的砂性土壤稻麦轮作农田N2O排放而言,所采用的观测方法未能检测到显著的秸秆还田效应和大气CO2浓度升高效应。 展开更多
关键词 n2o排放 秸秆还田 大气co2浓度升高 稻麦轮作
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Major factors controlling nitrous oxide emission and methane uptake from forest soil 被引量:3
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作者 张秀君 陈冠雄 徐慧 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期239-242,277,共5页
Soil samples were taken from depth of 0-12 cm in virgin broad-leaved Korean pine mixed forest in Changbai Moun-tain in July 2000. The effects of temperature, soil water content, pH, NH4+ and NO3- on N2O emission and C... Soil samples were taken from depth of 0-12 cm in virgin broad-leaved Korean pine mixed forest in Changbai Moun-tain in July 2000. The effects of temperature, soil water content, pH, NH4+ and NO3- on N2O emission and CH4 uptake of a for-est soil were studied in laboratory by the method of orthogonal design. It was observed under laboratory conditions in this study that there were significant correlations between N2O emission rate, CH4 oxidation rate, soil pH and temperature. Nevertheless, N2O emission rate also showed a significant positive correlation with CH4 oxidation rate. The results suggested that pH and temperature were important factors controlling N2O emission and CH4 oxidation under this experiment conditions. 展开更多
关键词 n2o emission CH4 uptake orthogonal design Forest soil
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Effects of Reduced Nitrogen Fertilization and Biochar Application on CO_2 and N_2O Emissions from a Summer Maize-Winter Wheat Rotation Field in North China 被引量:1
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作者 韩雪 范靖尉 +4 位作者 白晋华 任寰宇 李迎春 刁田田 郭李萍 《Agricultural Science & Technology》 CAS 2016年第12期2800-2808,共9页
This experiment was conducted in Xinxiang, Henan from June 2013 to June 2014. Total four treatments were designed including farmers ’ common practice (F, 250 kg/hm^2), 80% F (LF, 200 kg/hm^2), 80% F+biochar (LF... This experiment was conducted in Xinxiang, Henan from June 2013 to June 2014. Total four treatments were designed including farmers ’ common practice (F, 250 kg/hm^2), 80% F (LF, 200 kg/hm^2), 80% F+biochar (LFC) and no fertilizer (CK) to measure the dynamic emissions of CO2 and N2O from a summer maize-winter wheat field by static chamber-gas chromatography method. The results showed that the soil CO2 emission was 21.8-1 022.7 mg/(m^2·h), and was mainly influenced by soil temperature and moisture content. During the growth of summer maize, the soil CO2 emission was more significantly affected by soil moisture con-tent; and in winter wheat growing season, it was more significantly affected by soil temperature in the top 5 cm. The LF and LFC treatments significantly reduced the soil cumulative CO2 emission, especial y during the growth of winter wheat. Fertiliza-tion and irrigation were the main factors influencing the soil N2O emission. The soil N2O emission during the fertilization period accounted for 73.9%-74.5% and 40.5%-43.6% of the soil cumulative N2O emission during the summer maize-and winter wheat-growing season, respectively. The peak of emission fluxes was determined by fertilization amount, while the occurrence time of emission peak and emission re-duction effect were influenced by irrigation. The LF treatment reduced the soil cu-mulative N2O emission by 15.7%-16.8% and 18.1%-18.5% during the growth period of summer maize and winter wheat, respectively. Reduced nitrogen fertilization is an effective way for reducing N2O emission in intensive high-yielding farmland. Under a suitable nitrogen level (200 kg/hm^2), the application of biochar showed no significant effect on the soil N2O emission in a short term. The N2O emission factors of the L and LF treatments were 0.60% and 0.56%, respectively. ln the intensive high-yield-ing farmland of North China, reducing the nitrogen application amount is an appro-priate measure to mitigate greenhouse gas emissions without crop yield loss. 展开更多
关键词 Reduced nitrogen fertilization BIoCHAR Greenhouse gas emissions n2o emission Winter wheat-summer maize
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Effects of Bacillus amyloliquefaciens Biofertilizer on Brassica juncea var. multiceps Growth and N_2O Emission from Soil 被引量:2
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作者 白志辉 王璠 +3 位作者 曹建喜 吴尚华 徐圣君 马双龙 《Agricultural Science & Technology》 CAS 2015年第4期727-732,749,共7页
In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. m... In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. multiceps(XueIihong). Based on pot experiments in the greenhouse, the effects of chemical fertiIizers (CN), biofertiIizer (BF), inactivated broth (BI), starch wastewater (SW) and the combination of biofertiIizer and chemical fertiIizer (BC) on the yield, NO3- content and NO2- con-tent of XueIihong, soiI physicochemical properties and N2O emission were investi-gated. The resuIts showed that the yield of XueIihong in BC and CN treatments was improved by five times compared with CK; BF and SW treatments had insignifi-cant impact on the yield of XueIihong. Compared with CN treatment, BCL treatment exhibited simiIar improving effects on the yield of XueIihong, in which NO3- content of XueIihong and soiI was reduced by 16.4%-73.6% and 22%-29%, which reduced the risk of nitrogen eIuviations in soiI; average N2O fIux (FPV30) in BCL treatment was reduced by 58.3%-73.1% compared with CN treatment. In concIusion, B. amy-loliquefaciens is a feasibIe Iow-cost biofertiIizer for sustalnabIe vegetabIe farming with a great potential for starch wastewater utiIization. 展开更多
关键词 Bacil us amyloliquefaclens Wastewater from sweet potato starch pro-ductlon Brassica juncea var. multiceps Blofertliizer n2o emisslon
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