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Effect of tillage state of paddy soils with heavy metal pollution on the nosZ gene of N_(2)O reductase

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Journal of Environmental sciences 2024年第3期137卷 469-477页

作者： Liping Jiang Shiguang Liu Shanyun wang Libo Sun Guibing Zhu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of chinese academy of sciences Beijing 100049China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Paddy soils are an important source of atmospheric nitrous oxide(N_(2)O).However,numerous studies have focused on N_(2)O production during the soil tillage period,neglecting the N_(2)O production during the dry fallow *** this study,we conducted an incubation experiment using the acetylene inhibition technique to investigate N_(2)O emission and reduction rates of paddy soil profiles(0-1 m)from Guangdong Province and Jinlin Province in China,with different heavy-metal pollution *** abundance and community structures of denitrifying bacteria were determined via quantitative-PCR and Illumina MiSeq sequencing of nosZ,nirK,and nirS *** results showed that the potential N_(2)O emission rate,N_(2)O production rate,and denitrification rate have decreased with increasing soil vertical depth and heavy-metal *** importantly,we found that the functional gene type of N_(2)O reductase switched with the tillage state of paddy soils,which cladeⅡnos Z genes were the dominant gene during the tillage period,while cladeⅠnos Z genes were the dominant gene during the dry fallow *** heavy-metal pollution has less effect on the niche differentiation of the nos Z *** N_(2)O emission rate was significantly regulated by the genus Bradyhizobium,which contains both N_(2)O reductase and nitrite reductase *** findings suggests that the nos Z gene of N_(2)O reductase can significantly impact the N_(2)O emission from paddy soils.

关键词： Pappy soils N_(2)O reductase nosZ gene Heavy-metal pollution

Regularizing active set method for retrieval of the atmospheric aerosol particle size distribution function

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Regularizing active set method for retrieval of the atmosphe...

中国科学院地质与地球物理研究所2008学术年会

作者： Yanfei wang~* and Changchun Yang institute of Geology and Geophysics,{3. academy of sciences,P.O.Box 9825,beijing,10002.,China

The determination of flues aerosol particle size distribution function by using the particle spectrum extinction equation is an ill-posed integral equation of the first kind[***,***.18,188(1975);Y.P. wang,Computational Methods for Inverse Problems and Their Applications(Higher Education Press,2007)], since we are often faced with limited or insufficient observations in remote sensing and the observations are *** overcome the ill-posed nature of the problem,regularization techniques were developed. However,most of the literature focuses on the application of Phillips-Twomey regularization and its variants, which are unstable in several *** is known,the particle size distribution is always nomiegative,and we are often faced with incomplete ***,we study the active set method and propose a regularizing active set algorithm for ill-posed particle size distribution function retrieval and for enforcing nonnegativity in *** numerical tests are based on synthetic data for theoretical simulations and the field data obtained with a CE 3.8 Sun photometer for the Po Yang lake region of Jiang Xi Province,China,and are performed to show the efficiency and feasibility of the proposed algorithms.

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Variations in Column Concentration of Greenhouse Gases in China and Their Response to the 2015-2016 El Niño Event

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Journal of Meteorological Research 2024年第3期38卷 608-619页

作者： Ningwei LIU Lingjun XIA Youjun DOU Shaorou DONG Jing WEN Ying wang Rui FENG Ruonan wang Yuhe LI institute of atmospheric Environment China Meteorological AdministrationShenyang110166China Jiangxi Ecological Meteorology Centre Nanchang330096China beijing Xiangyuan academy of Meteorological Observing Technology Beijing100081China Climate Centre of Guangdong Province Guangzhou510641China Guangdong Meteorological Service Guangzhou510062China Liaoning Provincial Meteorological Equipment Support Centre Shenyang110166China Meteorological Centre of Northeast Air Traffic Administration of Civil Aviation of China Shenyang110161China

Since the industrial revolution,enhancement of atmospheric greenhouse gas concentrations as a result of human activities has been the primary cause of global *** monitoring and evaluation of greenhouse gases are significant prerequisites for carbon emission *** monthly data of global atmospheric carbon dioxide(CO_(2))and methane(CH4)column concentrations(hereinafter XCO_(2) and XCH_(4),respectively)retrieved by the Greenhouse Gas Observation Satellite(GOSAT),we analyzed the variations in XCO_(2)and XCH_(4)in China during 2010-2022 after confirming the reliability of the ***,the influence of a strong El Niño event in 2015-2016 on XCO_(2) and XCH_(4) variations in China was further *** results show that the retrieved XCO_(2) and XCH_(4) from GOSAT have similar temporal variation trends and significant correlations with the ground observation and emission inventory data of an atmospheric background station,which could be used to assess the variations in XCO_(2) and XCH_(4) in ***_(2) is high in spring and winter while XCH_(4) is high in *** XCO_(2) and XCH_(4) gradually declined from Southeast China to Northwest and Northeast China,with variation ranges of 401-406 and 1.81-1.88 ppmv,respectively;and the high value areas are located in the middle-lower Yangtze River ***_(2) and XCH_(4) in China increased as a whole during 2010-2022,with rapid enhancement and high levels of XCO_(2) and XCH_(4) in several *** significant increases in XCO_(2) and XCH_(4) over China in 2016 might be closely related to the strong El Niño-Southern Oscillation(ENSO)event during *** a global warming background in 2015,XCO_(2) and XCH_(4) increased by 0.768%and 0.657%in 2016 in *** analysis reveals that both the XCO_(2) and XCH_(4) variations might reflect the significant impact of the ENSO event on glacier melting in the Tibetan Plateau.

关键词： greenhouse gases column concentration CO_(2) CH4 El Niño-Southern Oscillation(ENSO) El Niño

Spatial pattern of Abies and Picea surface pollen distribution along the elevation gradient in the Qinghai-Tibetan Plateau and Xinjiang,China

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Spatial pattern of Abies and Picea surface pollen distributi...

中国科学院地质与地球物理研究所2008学术年会

作者： HOUYUAN LU,NAIQIN WU,XIANGDONG YANG,CAIMING SHEN,LIPING ZHU,LUO wang,QUAN LI,DEKE XU, GUOBANG TONG AND XIANGJUN SUN institute of Geology and Geophysics,{3. academy of sciences, beijing 10002.,China and institute of Tibetan Plateau Research,{3. academy of sciences,beijing 100085,China Naiqin Wu,Luo wang,Quan Li and Deke Xu,institute of Geology and Geophysics,{3. academy of sciences,beijing 10002.,China Xiangdong Yang,Nanjing institute of Limnology and Geography,{3. academy of sciences,Nanjing 210008,China Calming Shen,Department of Geography and Anthropology,Louisiana State University,Baton Rouge,LA 70803.USA and atmospheric sciences Research Center,State University of New York,Albany,New York 12203.USA Liping Zhu,institute of Tibetan Plateau Research,{3. academy of sciences,beijing 100085,China Guobang Tong,institute of Hydrology and Geology,{3. academy of Geological sciences,Zhengding 050803.China Xiangjun Sun,Laboratory of Marine Geology,Tongji University,Shanghai 200092,China

In this study we examine the relationships between Abies and Picea abundance in surface pollen and sub-alpine coniferous forest(SCF) distribution,elevation and climate in the Qinghai-Tibetan Plateau using a large modern pollen data set consisting of 857 *** indicate that Abies and Picea pollen are abundant in the southern and eastern Qinghai-Tibetan Plateau,where SCF dominates the *** percentages of both Abies and Picea show a unimodal pattern with changes in elevation and climate,and their optima occur at elevations from 2500 to 4000m a.s.l.,mean annual temperature from -1 to 10℃and mean annual precipitation from 450 to 850 *** optimal elevation of Abies and Picea pollen distribution decreases with latitude from c.4000 m in the south(21-3.°N) to c.2500 m in the north(43.49°N).

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沼泽湿地开垦对土壤水热条件和性质的影响

水土保持学报 2003年第6期17卷 144-147页

作者：宋长春阎百兴王毅勇赵志春娄彦景中国科学院东北地理与农业生态研究所

湿地具有重要的生态和环境功能。三江平原沼泽湿地的大面积垦殖,已对区域生态平衡及气候环境产生了一定的影响。湿地开垦后,土壤水、热条件发生较大变化,土壤温度的增高及氧化—还原条件的改变,促进了土壤有机质的分解和土壤呼吸通量的... 详细信息

湿地具有重要的生态和环境功能。三江平原沼泽湿地的大面积垦殖,已对区域生态平衡及气候环境产生了一定的影响。湿地开垦后,土壤水、热条件发生较大变化,土壤温度的增高及氧化—还原条件的改变,促进了土壤有机质的分解和土壤呼吸通量的增大。土壤有机碳、氮素含量随湿地开垦及开垦年限的增加而不断降低。沼泽湿地开垦初期5～7年,土壤有机碳及其它营养元素的含量变化幅度较大,持续耕作15～20年后,土壤有机碳损失曲线趋于平缓。湿地开垦后,土壤有机质输入量的减少及分解作用加强导致土壤容重和比重的增大,其变化趋势与土壤有机碳损失趋势相一致。

关键词：沼泽湿地垦殖水热条件土壤有机碳

The increase of snowfall in Northeast China after the mid-1980s

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chinese Science Bulletin 2013年第12期58卷 1350-1354页

作者： wang huijun ShengPing Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Graduate University of chinese academy of sciences

We studied long-term variation of winter snowfall in Northeast China (NEC) for 1951-2010. Results show that NEC snowfall increased about 20% during 1986-2010 relative to 1951-1985. Further investigation suggests that the snowfall increase is closely associated with weakening of the East Asian winter monsoon (EAWM). The physical processes were portrayed by this research. Weakening of EAWM led to weakened cold air flow from the north, thus resulted in the warming of the surface ocean along the Northeast Asia coast and more water vapor evaporated from the ocean surface to the atmosphere and further transported to NEC. Also, because of EAWM weakening, more water vapor from south, east and west of NEC was transported to NEC, increasing water vapor content and hence snowfall there. From an atmospheric circulation viewpoint, EAWM weakening strengthened convergence at low levels and divergence at high levels, thereby favoring increased vertical convection and snowfall.

关键词：中国东北地区降雪东亚冬季风中期年代海洋表面水汽含量大气环流

Observations and modeling of the ionospheric behaviors over the east Asia zone during the 22 July 2009 solar eclipse

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Observations and modeling of the ionospheric behaviors over ...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： huijun Le,Libo Liu,Feng Ding,Zhipeng Ren,Yiding Chen,Weixing Wan, Baiqi Ning,Guirong Xu,Min wang,Guozhu Li,Bo Xiong,and Lianhuan Hu 1 beijing National Observatory of Space Environment,{3. of Geology and Geophysics,chinese academy of sciences,beijing,China. 2 Also at Sate Key Laboratory of Space Weather,chinese academy of sciences,beijing,China. 3.{3. of Heavy Rain,China Meteorological Administration, Wuhan,China. 4 {3. of Earthquake Science,China Earthquake Administration, beijing,China. 5 Graduate School of the chinese academy of sciences,beijing,China.

[1]The longest total solar eclipse during the 21st century with a maximum duration of 6 min and 3. s occurred in South and East Asia on 22 July *** TEC data from four GPS stations in the total eclipse region(around 3.°N) from 105°E to 13.°E are used to study the variation in *** profiles of electron density from Formosa3.Cosmic satellites are used to study the height dependence of the electron density *** also modeled the eclipse effects on the ionosphere by an ionospheric *** the observations from F3.C and the modeled results show that there is an overall decrease in the electron density below F2 region,with the largest relative decrease occurring at Fl *** TEC observations show the delay time of the largest TEC decrease at the total eclipse region with regard to the maximum obscuration is less than five minutes and smaller than what is estimated from the time constant of the plasma loss rate at the F2 peak altitude although main contribution to TEC comes from the plasma density in the F2 *** modeling study shows that,due to the large plasma flux from topside ionosphere to F2 layer,the TEC response around 3.°N is mainly due to the electron density response at low altitudes(E and Fl region,200 km below) where the time delay of electron density response is very short(less than 4 min).Thus the time delay of TEC response would also be short as observed by GPS TEC.

关键词：

2011 Spring Seasonal Prediction of SDS in Northeast Asia Based on DGAEM

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2011 Spring Seasonal Prediction of SDS in Northeast Asia Bas...

第28届中国气象学会年会

作者： YANG Yuanqin,wang Jizhi,Niu Tao,Hou Qing Liu Yiyan,Chen Miao(atmospheric Composition Observing & Service Center,chinese {3. of Meteorological sciences,100081 beijing)

Here we use a Discriminant Genetic Algorithm Extended Model（DGAEM） to diagnose and predict seasonal sand and dust storm（SDS） activities occurring in Northeast *** study employed the regular meteorological data,including surface data,upper air data,and NCEP reanalysis data,collected from *** regional,seasonal,and annual differences of 3.D atmospheric circulation structures and SDS activities in the context of spatial and temporal distributions were *** algorithms were introduced with the further extension of promoting SDS seasonal predication from multi-level *** probability was used as a substitute for posterior probability of multi-level discriminants,to show the dual characteristics of crossover inheritance and mutation and to build a non-linear adaptability function in line with extended genetic *** has unveiled the spatial distribution of the maximum adaptability,allowing the forecast field to be defined by the population with the largest probability,and made discriminant genetic extension *** addition,the effort has led to the establishment of a regional model for predicting seasonal SDS activities in East *** model was tested to predict the spring SDS activities occurring in North China from 2007 to 2010 and made the prediction in springtime 2011 by this *** experimental forecast resulted in highly discriminant intensity ratings and regional distributions of SDS activities,which are a meaningful reference for seasonal SDS predictions in the future.

关键词： Discriminant Sand and Dust Storms Seasonal Prediction DGAEM Model

Relationship between Solar Wind-Magnetosphere Energy and Eurasian Winter Cold Events

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Advances in atmospheric sciences 2020年第6期37卷 652-661页

作者： Xinping XU Shengping HE huijun wang Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science and TechnologyNanjing 210044China Geophysical institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Climate Change Research Center Chinese Academy of SciencesBeijing 100029China

The profound impact of solar irradiance variations on the decadal variability of Earth’s climate has been investigated by previous ***,it remains a challenge to quantify the energetic particle precipitation(EPP)influence on the surface climate,which is an emerging research *** solar wind is a source of magnetospheric EPP,and the total energy input from the solar wind into Earth’s magnetosphere(Ein)shows remarkable interdecadal and interannual variability.B ased on the new Ein index,this study reveals a significant interannual relationship between the annual mean Einand Eurasian cold extremes in the subsequent *** frequent cold events are observed over Eurasia(primarily north of 50°N)following the higher-than-normal Ein activity in the previous year,accompanied by more frequent cold events over northern Africa,and vice *** response pattern shows great resemblance to the first empirical orthogonal function of the variability of cold extremes over Eurasia,with a spatial correlation coefficient of *** pronounced intensification of the positive North Atlantic Oscillation events and poleward shift of the North Atlantic storm track associated with the anomalously higher Ein favor the anomalous extreme atmospheric circulation events,and thus less frequent extreme cold temperatures over northern Eurasia on the interannual time *** is further hypothesized that the wave-mean flow interaction in the stratosphere and troposphere is favorable for the connection of Ein signals to tropospheric circulation and climate in the following winter.

关键词： Eurasian interannual winter