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Experimental study of population density using an optimized random forest model

Journal of Geographical Sciences 2024年第8期34卷 1636-1656页

作者： LI Lingling LIU Jinsong LI Zhi WEN Peizhang LI Yancheng LIU Yi School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China hebei Technology Innovation Center for Remote Sensing Identification of environmental Change Shijiazhuang 050024China Geocomputation and Planning Center of hebei Normal University Shijiazhuang 050024China hebei key laboratory of environmental Change and ecological construction Shijiazhuang 050024China

Random forest model is the mainstream research method used to accurately describe the distribution law and impact mechanism of regional *** took Shijiazhuang as the research area,with comprehensive zoning based on endowments as the modeling unit,conducted stratified sampling on a hectare grid cell,and systematically carried out incremental selection experiments of population density impact factors,optimizing the population density random forest model throughout the process(zonal modeling,stratified sampling,factor selection,weighted output).The results are as follows:(1)Zonal modeling addresses the issue of confusion in population distribution laws caused by a single *** on a grid cell not only ensures the quality of training data by avoiding the modifiable areal unit problem(MAUP)but also attempts to mitigate the adverse effects of the ecological *** sampling ensures the stability of population density label values(target variable)in the training sample.(2)Zonal selection experiments on population density impact factors help identify suitable combinations of factors,leading to a significant improvement in the goodness of fit(R^(2))of the zonal models.(3)Weighted combination output of the population density prediction dataset substantially enhances the model's robustness.(4)The population density dataset exhibits multi-scale superposition *** a large scale,the population density in plains is higher than that in mountainous areas,while on a small scale,urban areas have higher density compared to rural *** optimization scheme for the population density random forest model that we propose offers a unified technical framework for uncovering local population distribution law and the impact mechanisms.

关键词： population density random forest model endowment zones stratified sampling factor selection weighted output

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Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第3期35卷 197-208页

作者： Jinkuan Li Jianfeng Peng Xiaoxu Wei Meng Peng Xuan Li Yameng Liu Jiaxin Li College of Geography and environmental Science Henan UniversityKaifeng 475004People’s Republic of China key laboratory of Earth System Observation and Simulation of Henan province Kaifeng 475004People’s Republic of China

Global warming will affect growth strategies and how trees will *** compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu *** analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–*** difference of the climate response to slopes was small but not *** growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum *** regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–*** the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature *** results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response

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Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas

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Journal of Mountain Science 2024年第5期21卷 1647-1662页

作者： ZHANG Yunping LIN Jianping HUANG Yimin CHEN Zebin ZHU Chenhui YUAN Hao School of Geography and environmental Engineering Gannan Normal UniversityGanzhou 341000China key laboratory of Low Carbon Recycling Technology for Municipal Solid Waste in Jiangxi province Ganzhou 341000China

With rapid economic development,the size of urban land in China is expanding *** Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban *** delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the *** is of practical significance for the construction of green urban *** study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)*** the same time,considering the coupled coordination of"Production-Living-ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final *** results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability *** results of convex hull model show that the urban expansion type of Nankang is *** the future,the urban expansion will mainly occur in the northern part of the *** PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated *** final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study *** results of the delineation can promote

关键词： Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development

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Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate

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Forest Ecosystems 2024年第2期11卷 184-192页

作者： Zhengchao Ren Lei Liu Fang Yin Xiaoni Liu School of Earth Science and Resources Chang’an UniversityXi’an710054China Research Center of ecological construction and environmental Conservation in Gansu province Gansu Agricultural UniversityLanzhou730070China State key laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China School of Land Engineering Chang’an UniversityXi’an710054China College of Pratacultural Science Gansu Agricultural UniversityLanzhou730070China

Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention ***,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate *** this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation *** achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV *** find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and ***,we observe an unexpected transition between tundra and savanna despite their geographical *** shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each ***,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing *** spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.

关键词： Potential natural vegetation Global warming Vegetation classification Predicted model CSCS

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Atmospheric nitrogen deposition affects forest plant and soil system carbon:nitrogen:phosphorus stoichiometric flexibility:A meta-analysis

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Forest Ecosystems 2024年第3期11卷 307-317页

作者： Xiyan Jiang Xiaojing Wang Yaqi Qiao Yi Cao Yan Jiao An Yang Mengzhou Liu Lei Ma Mengya Song Shenglei Fu key laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions College of Geography and Environmental ScienceHenan UniversityKaifeng475004China Henan key laboratory of Integrated Air Pollution Control and ecological Security College of Geography and Environmental ScienceHenan UniversityKaifeng475004China Henan Dabieshan National Field Observation and Research Station of Forest Ecosystem Henan UniversityZhengzhou450046China

Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant ***,the effect of N deposition on the flexibility of carbon(C),N,and phosphorus(P)in forest plant-soil-microbe systems remains ***:We conducted a meta-analysis based on 751 pairs of observations to evaluate the responses of plant,soil and microbial biomass C,N and P nutrients and stoichiometry to N addition in different N intensity(050,50–100,>100 kg·ha^(-1)·year^(-1)of N),duration(0–5,>5 year),method(understory,canopy),and matter(ammonium N,nitrate N,organic N,mixed N).Results:N addition significantly increased plant N:P(leaf:14.98%,root:13.29%),plant C:P(leaf:6.8%,root:25.44%),soil N:P(13.94%),soil C:P(10.86%),microbial biomass N:P(23.58%),microbial biomass C:P(12.62%),but reduced plant C:N(leaf:6.49%,root:9.02%).Furthermore,plant C:N:P stoichiometry changed significantly under short-term N inputs,while soil and microorganisms changed drastically under high N *** N addition primarily affected plant C:N:P stoichiometry through altering plant N content,while understory N inputs altered more by influencing soil C and P *** N significantly influenced plant and soil C:N and C:P,while ammonia N changed plant N:*** C:P and soil C:N were strongly correlated with mean annual precipitation(MAT),and the C:N:P stoichiometric flexibility in soil and plant under N addition connected with soil ***,N addition decoupled the correlations between soil microorganisms and the ***:N addition significantly increased the C:P and N:P in soil,plant,and microbial biomass,reducing plant C:N,and aggravated forest P ***,these impacts were contingent on climate types,soil layers,and N input *** findings enhance our comprehension of the plant-soil system nutrient cycling mechanisms in forest ecosystems and plant strategy responses to N deposition.

关键词： C:N:P stoichiometry Meta-analysis Forest ecosystem Nitrogen addition form Nutrient cycles

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Health risk assessment of municipal solid waste incineration emissions based on regression analysis

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Eco-Environment & Health 2024年第3期3卷 338-346页

作者： Zhuoshi Huang Jicui Cui Abdoulaye Boré Wenchao Ma Ziyi Zhang Zhi Qiao Ziyang Lou Johann Fellner School of environmental Science and Engineering Tianjin UniversityTianjin 300072China key laboratory of Agro-Forestry environmental Processes and ecological Regulation of Hainan province College of Ecology and EnvironmentHainan UniversityHaikou 570228China Offshore environmental Technology&Services Limited Beijing 100027China Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery School of Environmental Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Christian Doppler laboratory for Anthropogenic Resource Institute for Water Quality and Resource ManagementTU WienKarlsplatz 13/2261040 ViennaAustria

This study examined the potential health risks posed by the operation of 96 waste-to-energy(WtE)plants in 30 cities in the Bohai Rim of *** a sophisticated simulation approach,the Weather Research and Forecasting(WRF)model coupled with the California Puff(CALPUFF)model,we obtained the spatial distribution of pollutants emitted by WtE plants in the *** indices(HI)and cancer risks(CR)were calculated for each plant using the United States environmental Protection Agency's recommended *** results indicated that both HIs and CRs were generally low,with values below the accepted threshold of 1.0 and 1.0×10^(-6),***,the average HI and CR values for the entire study area were 2.95×10^(-3)and 3.43×10^(-7),***,some variability in these values was observed depending on the location and type of WtE plant.A thorough analysis of various parameters,such as waste composition,moisture content,and operating conditions,was conducted to identify the factors that influence the health risks associated with *** findings suggest that proper waste sorting and categorization,increased cost of construction,and elevated height of chimneys are effective strategies for reducing the health risks associated with ***,this study provides valuable insights into the potential health risks associated with WtE plants in the Bohai Rim region of *** findings can serve as useful guidelines for law enforcement wings and industry professionals seeking to minimize the risks associated with municipal solid waste(MSW)management and promote sustainable development.

关键词： Incineration WRF/CALPUFF Health risk assessment Ridge regression model MSW classification

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Preface:Heavy metal(loid)s at mining&metallurgical sites:Fate,risk and remediation

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Journal of Central South University 2024年第4期31卷 1033-1035页

作者：薛生国李楚璇赵东叶吴川 School of Metallurgy and Environment Central South UniversityChangsha 410083China Department of Civil Constructionand Environmental EngineeringSan Diego State UniversitySan DiegoCA 92182USA

The contamination of heavy metal(loid)s at mining&metallurgical sites has been a major environmental challenge worldwide[1].Typically,large amounts of metal(loid)s-bearing wastes are generated at these sites,such as smelting slag,combustion residues,mine tailings,wastewater,and exhaust gas[2].Due to their high mobility in the environment,the released heavy metal(loid)s can easily enter the soil and water environment,posing long-term and widespread threats to ecological and human health[3].

关键词： mining wastewater smelting

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Spatiotemporal Evolution of ecological Quality in Alpine Freshwater Lake Nature Reserves in the Past 20 Years

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Meteorological and environmental Research 2024年第2期15卷 29-36页

作者： Denghong HUANG Chenli LIAO Zhenzhen ZHANG Jintong REN Guizhou University of Engineering Science/Guizhou province key laboratory of ecological Protection and Restoration of Typical Plateau Wetlands Bijie 551799China School of Karst Science Guizhou Normal UniversityGuiyang 550025China School of Geography&environmental Science Guizhou Normal UniversityGuiyang 550025China

The Caohai Nature Reserve is one of the three major plateau freshwater lakes in *** the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation of the spatiotemporal evolution trend of the ecological quality of the Caohai Nature Reserve is significant for the maintenance and construction of the ecosystem in this *** research is based on the Google Earth Engine(GEE)remote sensing cloud computing *** TM/OLI images from May to October in five time periods:2000-2002,2004-2006,2009-2011,2014-2016,and 2019-2021 were obtained to reconstruct the optimal cloud image set by averaging the images in each time *** constructing four ecological indicators:Greenness(NDVI),Wetness(Wet),Hotness(LST),and Dryness(NDBSI),and using Principal Component Analysis(PCA)method to obtain the Remote Sensing ecological Index(RSEI)for the corresponding years,the spatiotemporal variation of ecological quality in the Caohai Nature Reserve over 20 years was *** results indicate:①the mean value of RSEI increased from 0.460 in 2000-2002 to 0.772 in 2019-2021,a 67.83%increase,indicating a significant improvement in the ecological quality of the reserve over the 20 years;②from the perspective of functional zoning of the Caohai Nature Reserve,the ecological quality of the core area showed a degrading trend,while the ecological quality of the buffer zone and experimental zone significantly improved;③with the implementation of ecological restoration projects,the ecological quality of the reserve gradually recovered and improved from 2014 to *** trend of RSEI value changes is well correlated with human interventions,indicating that the PCA-based RSEI model can be effectively used for ecological quality assessment in lake areas.

关键词： ecological restoration ecological quality Remote sensing ecological index Google Earth Engine Caohai Nature Reserve

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Trade-off analyses between food provision and soil conservation service of Grain for Green Program in Mountainous Area

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International Soil and Water Conservation Research 2024年第1期12卷 43-53页

作者： Yawen Li Yuxiang Li Xingwu Duan Zhongyin Cai Ya Li Baiyun He Long Yin Institute of International River and Eco-security Yunnan UniversityKunming650091PR China Yunnan key laboratory of International Rivers and Trans-boundary Eco-security Kunming650091PR China State key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085PR China University of Chinese Academy of Sciences Beijing100049PR China

The Grain for Green Program and soil and water conservation engineering initiatives are crucial for controlling erosion in steep-slope ***,it is still unclear how these two management methods should be carried out in respect to the situation in mountainous ***,taking a typical mountainous area in southwest China as an example,we simulated six scenarios in order to compare the food provisioning service(FPS)and soil conservation service of the Grain for Green Program(converting to grassland)and construction Measures(converting to sloping terrace)under different *** showed that when farmland with a>25°slope was converted into grassland,the amount of soil erosion(M)decreased by 21.0%,while FPS decreased by only 0.7%.However,when farmland with a>25°slope was converted into sloping terrace,M decreased by 31.3%while FPS increased by 18.7%.With the increases of farmland slope ranges in the construction Measures scenario,M gradually decreased and FPS gradually *** when farmland>15°was converted into sloping terrace,M decreased by 63.9%and FPS increased by 52.7%.Furthermore,the trade-offs of construction Measures are lower than that of Grain for Green on different slope ***,we conclude that construction Measures are a more suitable method in mountainous areas than the Grain for Green,and we suggest that further research be conducted to consider the ecological risks of construction engineering measures.

关键词： Soil erosion Grain for green construction measures Mountainous areas

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Response mechanism of soil microorganisms to simulated precipitation in the source wetland of Qinghai Lake

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ecological Processes 2024年第2期13卷 61-71页

作者： Xinye Wang Ni Zhang Kelong Chen Tiexi Chen Desheng Qi Yuanxi Ma School of Geographical Sciences Qinghai Normal University National Positioning Observation and Research Station of Qinghai Lake Wetland Ecosystem in Qinghai National Forestry and Grassland Administration key laboratory of Tibetan Plateau Land Surface Processes and ecological Conservation(Ministry of Education) Qinghai Normal University School of Geographical Sciences Nanjing University of Information Science and Technology Qinghai Provincial land spatial Planning Research Institute

Background Changes in precipitation patterns crucially impact soil microbial communities, and the ecosystem in Qinghai-Tibet Plateau(QTP) is highly vulnerable to climate change. However, we do not fully understand how soil microbial communities in the source wetlands of QTP respond to changes in precipitation. In this study, we employed advanced techniques such as high-throughput sequencing and metabolomics to investigate how soil microbial communities in a source wetland of Qinghai Lake respond to changes in precipitation after quadrennial precipitation *** Our findings showed that the predominant microbiota in the source wetland was Proteobacteria. Interestingly, alterations in precipitation levels, whether increased or reduced, did not significantly impact the diversity or functional groups of the microbial community. However, the structure of the microbial community did respond notably to changes in precipitation, leading to shifts in the relative abundance of Spirochaetes and Treponema. A notable finding was that reduced precipitation levels(– 25% and-50%) and mild increases in precipitation(25%) within the region contributed to increased soil carbon content. However, this effect ceased to manifest when precipitation increased by 50%. Additionally, the reduction in precipitation prompted the release of soil metabolites like syringic acid and aldosterone, while enhanced precipitation resulted in a decrease in aldosterone *** Precipitation changes altered the relative abundance of soil microbial communities and metabolites, which was conducive to increasing carbon storage in this alpine wetland.

关键词： Qinghai-Tibet Plateau Climate change Precipitation gradient Carbon and nitrogen cycles LC/MS

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