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Distribution and mapping of temperate savanna in the sandy lands of eastern China

Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi LU institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry institute of Great Green Wall Satellite Application Centre for Ecology and environment MEE institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research institute Chinese Academy of Sciences institute of Forest Resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Accurate quantification of the algebraic,multiplicative algebraic,and simultaneous iterative reconstruction techniques in ionosphere rebuilding based on the TIEGCM assessment

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Earth and Planetary Physics 2025年第1期9卷 117-126页

作者： Ao Qi HaiBing Ruan institute of Space Weather Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Geospace environment University of Science&Technology of ChinaChinese Academy of SciencesHefei 230026China

The algebraic reconstruction technique(ART),multiplicative algebraic reconstruction technique(MART),and simultaneous iterative reconstruction technique(SIRT)are computational methodologies extensively utilized within the field of computerized ionospheric tomography(CIT)to facilitate three-dimensional reconstruction of the ionospheric ***,reconstruction accuracy elicits recurrent disputes over its practical application,and people usually attribute this issue to incomplete and uneven coverage of the *** Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM)offers a reasonable physics-based ionospheric background and is widely utilized in ionospheric *** use the TIEGCM simulations as the targeted ionosphere because the current measurements are far from able to realistically reproduce the ionosphere in *** designations of satellite measurements are conducted to investigate the limiting performance of CIT methods in ionospheric *** to common practice,electron density distributions from outputs of the International Reference Ionosphere(IRI)model are used as the iterative initial value in CIT *** outcomes suggest that despite data coverage,iterative initial conditions also play an essential role in ionospheric *** particular,in the longitudinal sectors where the iterative initial height of the F2-layer peak electron density(hmF2)differs substantially from the background densities,none of the three CIT methods can reproduce the exact background *** hmF2 is close but the ionospheric F2-layer peak density(NmF2)is different between the targeted background and initial conditions,the MART performs better than the ART and SIRT,as evidenced by the correlation coefficients of MART being above 0.97 and those of ART and SIRT being below *** summary,this investigation reveals the potential uncertainties in traditional CIT reconstruction,particularly when reali

关键词： computerized ionospheric tomography International Reference Ionosphere model Thermosphere Ionosphere Electrodynamics General Circulation model ionosphere

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Inactivation of Poliovirus by Ozone and the Impact of Ozone on the Viral Genome

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Biomedical and environmental Sciences 2019年第5期32卷 324-333页

作者： JIANG Han Ji CHEN Na SHEN Zhi Qiang YIN Jing QIU Zhi Gang MIAO Jing YANG Zhong Wei SHI Dan Yang WANG Hua Ran WANG Xin Wei LI Jun Wen YANG Dong JIN Min Department of environment and Health Tianjin Institute of Environmental & Operational Medicine Key Laboratory of Risk Assessment and Control for Environment & Food Safety

Objective To investigate the mechanisms underlying ozone-induced inactivation of poliovirus type 1(PV1). Methods We used cell culture, long‐overlapping RT‐PCR, and spot hybridization assays to verify and accurately locate the sites of action of ozone that cause PV1 inactivation. We also employed recombinant viral genome RNA infection models to confirm our observations. Results Our results indicated that ozone inactivated PV1 primarily by disrupting the 5′-non‐coding region(5′‐NCR) of the PV1 genome. Further study revealed that ozone specifically damaged the 80‐124 nucleotide(nt) region in the 5′-NCR. Recombinant viral genome RNA infection models confirmed that PV1 lacking this region was non‐infectious. Conclusion In this study, we not only elucidated the mechanisms by which ozone induces PV1 inactivation but also determined that the 80‐124 nt region in the 5′‐NCR is targeted by ozone to achieve this inactivation.

关键词： Poliovirus Poliomyelitis Ozone Disinfection

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Abiotic transformation of synthetic progestins in representative soil mineral suspensions

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Journal of environmental Sciences 2023年第5期127卷 375-388页

作者： Xingjian Yang Rui Wang Zhili He Xiong Dai Xiuping Jiang He Liu Yongtao Li College of Natural Resources and environment Joint Institute for Environment&EducationSouth China Agricultural UniversityGuangzhou 510642China State environmental Protection Key Laboratory of environmental Pollution Health Risk assessment South China Institute of Environmental ScienceMinistry of Ecology and EnvironmentGuangzhou 510655China

Altrenogest(ALT),drospirenone(DRO),and melengestrol acetate(MLA)are three highly potent synthetic progestins that can be released into agricultural soils,while their fate in soil minerals remains *** study explored the transformation of these progestins in MnO_(2),SiO_(2),and ferrihydrite suspensions and identified their transformation products(TPs)via high resolution mass spectrometry and density functional theory *** were only observed for DRO and MLA in SiO_(2) suspension and ALT in MnO_(2) suspension(half-lives=0.86 min–9.90 day).ALT transformation was facilitated at higher MnO_(2) loadings,while DRO and MLA transformations were inhibited at higher SiO_(2) *** data indicated that hydrophobic partitioning interactionwas dominant at higher SiO_(2) loadings rather than specific interaction,which limited subsequent surface-catalyzed *** transformation rate decreased with increasing pH because MnO_(2) reduction requires proton *** contrast,relatively high pH facilitated MLA and DRO transformation,indicating that base-catalyzed hydrolysis occurred in SiO_(2) *** clustermap demonstrated the formation of abundant *** ring and acetoxy group hydrolysis was the major transformation pathway for DRO and MLA,with estimated yields of 57.7%and 173.2%at 6 day,*** experienced C12 hydroxylation and formed the major TP 326g(yield of 15.4%at 8 hr).ALT also experienced allyl group oxidation and subsequent C5 hydroxylation,forming the major TP 344a(yield of 14.1%at 8 hr).This study demonstrates that TPs ofmetastable progestins are likely the main species in soils and that TP identification is a particular priority for risk assessment.

关键词： Altrenogest Drospirenone Melengestrol acetate Transformation products Hydrolysis Oxidation

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Seroprevalence and evolutionary dynamics of genotype 4 hepatitis E virus in Shandong Province,China

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World Journal of Gastroenterology 2014年第24期20卷 7955-7963页

作者： Dong Yang Mei Jiang Min Jin Zhi-Gang Qiu Zhi-Qiang Shen Wei-Hong Cui Da-Ning Wang Lian-Feng Gong Bo Li Xin-Wei Wang Jun-Wen Li Department of environment and Health Tianjin Institute of Health and Environmental Medicine Key Laboratory of Risk assessment and Control for environment and Food Safety Yantai Center for Disease Control and Prevention

AIM: To investigate the seroprevalence and evolutionary dynamics of hepatitis E virus (HEV) and assess the ancestor of HEVs in China’s Shandong Province.

关键词： Hepatitis E virus Zoonotic Cross-species transmission Trans-regional transmission Evolutionary dynamics

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An Improved, Downscaled, Fine Model for Simulation of Daily Weather States

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Advances in Atmospheric Sciences 2011年第6期28卷 1357-1366页

作者：江志红丁裕国郑春雨陈威霖 Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science & Technology environment assessment Northeast Electric Power Design Institute

In this study,changes in daily weather states were treated as a complex Markov chain process,based on a continuous-time watershed model（soil water assessment tool,SWAT） developed by the Agricultural Research Service at the *** of Agriculture（USDA-ARS）.A finer classification using total cloud amount for dry states was adopted,and dry days were classified into three states：clear,cloudy,and overcast（rain free）.Multistate transition models for dry-and wet-day series were constructed to comprehensively downscale the simulation of regional daily climatic *** results show that the finer,improved,downscaled model overcame the oversimplified treatment of a two-weather state model and is free of the shortcomings of a multistate model that neglects finer classification of dry days（i.e.,finer classification was applied only to wet days）.As a result,overall simulation of weather states based on the SWAT greatly improved,and the improvement in simulating daily temperature and radiation was especially significant.

关键词： stochastic simulation daily weather state series Markov chain state vector.

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Time-first approach for land cover mapping using big Earth observation data time-series in a data cube-a case study from the Lake Geneva region(Switzerland)

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Big Earth Data 2024年第3期8卷 435-466页

作者： Gregory Giuliani institute for environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland United Nations environment Programme Division of Early Warning and AssessmentGenevaSwitzerland

Accurate,consistent,and high-resolution Land Use&Cover(LUC)information is fundamental for effectively monitoring landscape dynamics and better apprehending drivers,pressures,state,and impacts on land ***,the availability of such national products with high thematic accuracy is still limited and consequently researchers and policymakers are constrained to work with data that do not necessarily reflect on-the-ground realities impending to correctly capture details of landscape features as well as limiting the identification and quantification of drivers and rate of ***,we took advantage of the Switzerland’s official LUC statistical sampling survey and dense time-series of Sentinel-2 data,combining them with Machine and Deep Learning methods to produce an accurate and high spatial resolution land cover map over the Lake Geneva *** suggest that time-first approach is a valuable alternative to space-first approaches,accounting for the intra-annual variability of classes,hence improving classification *** demonstrate that Deep Learning methods outperform more traditional Machine Learning ones such as Random Forest,providing more accurate predictions with lower *** produced land cover map has a high accuracy,an improved spatial resolution,while at the same time preserving the statistical significance(*** proportion)of the official national *** work paves the way towards the objective to produce a yearly high resolution land cover map of Switzerland and potentially implement a continuous land change monitoring *** further work is required to properly address challenges such as the need for increased temporal resolution for LUC information or the quality of training samples.

关键词： Land cover Sentinel-2 timeseries SITS Arealstatistik

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Global and Regional Surface Nitrogen Balances in Intensive Agricultural Production Systems for the Period 1970-2030

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Pedosphere 2005年第2期15卷 137-155页

作者： A. F. BOUWMAN G.Van DRECHT K. W. Van der HOEK Netherlands environmental assessment Agency Netherlands Environmental Assessment AgencyLaboratory for Environmental Monitoring National Institute for Public Health and the EnvironmentP .O. Box 13720 BA Bilthoven (The Netherlands)National Institute for Public Health and the EnvironmentP .O. Box 13720 BA Bilthoven (The Netherlands)National Institute for Public Health and the EnvironmentP. O. Box 13720 BA Bilthoven (The Netherlands)

Global nitrogen (N) budgets for intensive agricultural systems were compiled for a 0.5 by 0.5 degree resolution. These budgets include N inputs (N fertilizer, animal manure, biological N fixation and atmospheric N deposition) and outputs (N removal from the field in harvested crops and grass and grass consumption by grazing animals, ammonia volatilization,denitrification and leaching). Data for the historical years 1970 and 1995 and a projection for 2030 were used to study changes in the recovery of N and the different loss terms for intensive agricultural systems. The results indicate that the overall system N recovery and fertilizer use efficiency slowly increased in the industrialized countries between 1970 and 1995, the values for developing countries have decreased in the same period. For the coming three decades our results indicate a rapid increase in both the industrialized and developing countries. High values of ＞ 80% for fertilizer use efficiency may be related to surface N balance deficits, implying a depletion of soil N and loss of soil fertility. The projected intensification in most developing countries will cause a gradual shift from deficits to surpluses in the coming *** projected fast growth of crop and livestock production, and intensification and associated increase in fertilizer inputs will cause a major increase in the surface N balance surplus in the coming three decades. This implies increasing losses of N compounds to air (ammonia, nitrous oxide and nitric oxide), and groundwater and surface water (nitrate).

关键词： animal manure fertilizer intensive agriculture nitrogen surface balance

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Pollution characteristics and ecological risk assessment of glucocorticoids in the Jiangsu section of the Yangtze River Basin

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Frontiers of environmental Science & Engineering 2024年第11期18卷 159-168页

作者： Lichao Tan Keke Xu Shengxin Zhang Fukai Tang Mingzhu Zhang Feng Ge Kegui Zhang Nanjing institute of environmental Sciences Ministry of Ecology and Environment of the People’s Republic of ChinaNanjing 210042China Key Laboratory of Pesticide environmental assessment and Pollution Control Ministry of Ecology and Environment of the People’s Republic of ChinaNanjing 210042China

Glucocorticoids,which are one of the most extensively used steroid hormones,are typical endocrine *** recent years,glucocorticoids have been widely detected in surface waters such as rivers and lakes,but there are relatively few studies focusing on their ecological risk *** this study,the pollution characteristics of seven glucocorticoids were studied in the Jiangsu section of the Yangtze River Basin,and ecological risk assessments were performed using the risk quotient *** results showed that seven glucocorticoids were detected at different levels at eight sampling *** these glucocorticoids,prednisone had the highest value of 238.27 ng/L in the wet season,with pollution levels significantly higher than those reported in other *** ecological risk evaluation showed that prednisone,prednisolone,dexamethasone,and hydrocortisone acetate all had risk quotient values greater than 1 in the studied water environment,posing a high ecological *** study provides a scientific foundation for the in-depth study of the pollution characteristics and ecological risk of glucocorticoids in water bodies in the Jiangsu section of the Yangtze River Basin.

关键词： Yangtze River Basin Glucocorticoids Pollution characteristics Ecological risk assessment

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Research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu Hong Li Yuanyuan Ji Xin Zhang Likun Xue Jian Gao Cong An State Key Laboratory of environmental Criteria and Risk assessment Chinese Research Academy of Environmental SciencesBeijing 100012China environment Research institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control *** paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in *** overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be *** are still some current deficiencies in the study field in ***,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

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