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Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in changchun,Northeast China:implications for urban carbon stock improvement

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Journal of Forestry Research 2024年第2期35卷 146-162页

作者： Yuanyuan Wang Xinzhu Dai Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui Academy of Forestry Sciences of changchun Bureau of Forestry and Landscaping of ChangchunChangchun 130117People’s Republic of China College of Landscape Architecture Changchun UniversityChangchun 130022People’s Republic of China changchun South Lake Park Bureau of Forestry and Landscaping of ChangchunChangchun 130012People’s Republic of China

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of *** clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in changchun,which had the largest green quantity and carbon density *** found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer *** conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus *** addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,*** findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

关键词： Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests

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RELATIONSHIPS BETWEEN FRACTIONATIONS OF Pb, Cd, Cu, Zn AND Ni AND SOIL PROPERTIES IN URBAN SOILS OF changchun, CHINA

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Chinese Geographical Science 2005年第2期15卷 179-185页

作者： GUOPing XIEZhong-lei LIJun KANGChun-li LIUJian-hua CollegeofEnvironmentandResources JilinUniversityChangchun130012P.R.China CollegeofEnvironmentandResources JilinUniversityChangchun130012P.R.China／／CollegeofEarthSciencesJilinUniversityChangchun130026P.R.China JilinProvincialAcademyforEnvironmentalScience Changchun130021P.R.China

An extensive soil investigation was conducted in different domains of changchun to disclose the fractionations of Pb, Cu, Cd, Zn and Ni in urban soils. Meanwhile correlation analysis and multiple stepwise regressions were used to define relationships between soil properties and metal fractions and the chief factors influencing the fractionation of heavy metals in the soils. The results showed that Pb, Ni and Cu were mainly associated with the residual and organic forms; most of Cd was concentrated in the residual and exchangeable fractions. Zn in residual and carbonate fraction was the highest. The activities of the heavy metals probably declined in the following order: Cd, Zn, Pb, Cu and Ni. The chemical fractions of heavy metals in different domains in changchun City were of significantly spatial heterogeneity. Soil properties had different influences on the chemical fractions of heavy metals to some extent and the main factors influencing Cd, Zn, Pb, Cu and Ni fractionation and transformation were apparently different.

关键词： urban soils heavy metal fractionation soil properties

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STRATEGIC ENVIRONMENT ASSESSMENT ON LAND-USE PLANNING-A Case Study of changchun Economic and Technological Zone

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Chinese Geographical Science 2002年第3期12卷 262-267页

作者： ZHANGYan SHANGJin－cheng 等 changchunInstiuteofGeography theChineseAcademyofSciencesChangchun130021P.R.China DepartmentofEnvironmentSciences NortheastNormalUniversityChangchun130024P.R.China

The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use *** whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla *** those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.

关键词： land-use planning strategic environment assessment synthetically integratedmethods

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Lockdown-induced Urban Aerosol Change over changchun, China During COVID-19 Outbreak with Polarization LiDAR

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Chinese Geographical Science 2022年第5期32卷 824-833页

作者： CHEN Weiwei DUANMU Lingjian QIN Yang YANG Hongwu FU Jing LU Chengwei FENG Wei GUO Li Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of Sci-encesChangchun 130102China College of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China Jilin Provincial Ecological Environment Monitoring Center Changchun 130012China Hongke Photonics Company Liaoyuan 136200China The Department of Ophthalmology The First Hospital of Jilin UniversityChangchun 130021China Key Lab of Groundwater Resources and Environment Jilin UniversityChangchun 130021China

Depending on various government policies,COVID-19(Corona Virus Disease-19) lockdowns have had diverse impacts on global aerosol *** 2022,changchun a provincial capital city in Northeast China,suffered a severe COVID-19 outbreak and implemented a very strict lockdown that lasted for nearly two *** ground-based polarization Light Detection and Ranging(LiDAR),we detected real-time aerosol profile parameters(EC,extinction coefficient;DR,depolarization ratio;AOD,aerosol optical depth),as well as air-quality and meteorological indexes from 1 March to 30 April in 2021 and 2022 to quantify the effects of lockdown on aerosol *** period in 2022 was divided into three stages:pre-lockdown(1-10 March),strict lockdown(11 March to 10 April),and partial lockdown(11-30 April).The results showed that,during the strict lockdown period,compared with the pre-lockdown period,there were substantial reductions in aerosol parameters(EC and AOD),and this was consistent with the concentrations of the atmospheric pollutants PM_(2.5)(particulate matter with an aerodynamic diameter ≤2.5 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter ≤10 μm),and the Oconcentration increased by 8.3%.During the strict lockdown,the values of EC within0-1 km and AOD decreased by 16.0% and 11.2%,respectively,as compared to the corresponding period in *** reduced the conventional and organized emissions of air pollutants,and it clearly delayed the time of seasonal emissions from agricultural burning;however,it did not decrease the number of farmland fire *** meteorological factors and eliminating the influence of wind-blown dust events,the results showed that reductions from conventional organized emission sources during the strict lockdown contributed to a 30% air-quality improvement and a 22% reduction in near-surface extinction(0-2 km).Aerosols produced by urban epidemic prevention and disinfection can also be identified using the ***

关键词： PM_(2.5)(particulate matter with an aerodynamic diameter≤2.5μm) NO2 O3 aerosol optical depth(AOD) extinction coefficient depolarization ratio COVID-19(Corona Virus Disease-19)lockdown

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Uneven Distribution of Primary and Middle Schools:A Case Study of changchun,China

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Frontiers of Education in China 2018年第4期13卷 633-655页

作者： YAN Qing LI Chenggu ZHANG Jing MA Zuopeng LUO Fenglong School of Geographical Sciences Northeast Normal UniversityChangchun 130024China changchun Urban and Rural Planning and Design Institute Changchun 130021China

Providing further knowledge to and refinement of public facility location theory,this paper focuses on the distribution of basic educational facilities in *** aim towards an equilibrium in the distribution of education resources has captured widespread attention in recent *** basis of an education equilibrium is the balanced distribution of teaching *** the spatial analysis function of ArcGIS,this article discusses the evolution characteristics of education equilibrium and explores its dynamics with reference to primary and middle schools in changchun City,Jilin Province from 2007 to *** study found the spatial distribution of primary and middle schools in changchun was uneven and the characteristic of close internal but sparse external has not ***-level equilibrium of primary and middle schools in changchun has been basically realized,but high-level equilibrium is far from being *** there has been a trend towards suburbanization of these schools in recent years,the high entrance threshold has determined that high-quality school opportunity(schools with high-level resource allocation)has not increased for *** spatial distribution of primary and middle schools is related to the factors of population,real estate,transportation and the education system *** space,living space,and traffic space all interact and together affect urban spatial structure.

关键词： layout equilibrium spatial distribution equilibrium spatial location equilibrium quality equilibrium influence factor primary and middle schools

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Influential Intensity of Urban Agglomeration on Evolution of Ecoenvironmental Pressure:A Case Study of changchun,China

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Chinese Geographical Science 2017年第4期27卷 638-647页

作者： LIU Yanjun ZHANG Jing LI Chenggu ZHOU Guolei FU Zhanhui LIU Degang School of Geography Sciences Northeast Normal UniversityChangchun 130024China

In this paper,we study the interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental *** build an index system for evaluating the agglomeration of urban elements and eco-environmental *** the entropy method and response intensity model,we analyze how urban elements agglomeration influenced eco-environmental pressure in changchun from 1990 to 2012,eliciting the changing features and influential ***,we conclude there is a significant interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental pressure in *** is inferred from the degree of this agglomeration in changchun having increased since 1990,with the degree of eco-environmental pressure first decreasing and then *** this,the impact of urban elements agglomeration on eco-environmental pressure has changed from negative to *** main reasons behind this shift are arguably the rapid growth of urban investment and ongoing urbanization.

关键词： urban elements agglomeration eco-environmental pressure influential intensity response index changchun China

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STUDY ON FLUXES OF CH4 EMISSION FROM PADDY FIELDS IN changchun AREA

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Chinese Geographical Science 2000年第3期10卷 91-96页

作者： Min-hua Yan Xue-hui Ma De-xuan Wang changchun Institute of Geography the Chinese Academy of Sciences 130021 Changchun P. R. China

Little has been done in measurement and research of the flux of CH4 emission from paddy fields in changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of CH4 emission flux and to discuss the factors which affect CH4 emission from paddy fields. Experimental paddy fields are chosen using TM pictures respectively in Xinlicheng (43° 49′ N, 125° 20′ E) of the Yitong River’s and in Wanchang (43° 44′ 10″ N, 125° 53′ 11″ E) of the Yinma River’s alluvial plain. The fluxes of CH4 emission from paddy fields are measured by the method of static chamber in changchun area in 3 consecutive years. The research results show that the peak of CH4 emission from paddy fields occurs during the booting stage. The mean fluxes of CH4 emission are 7.056 mg/(m2· h) and 0.489 mg/(m2· h) in the paddy fields of flood and discontinuous irrigation respectively. The contrastive study holds that climate condition, the way of water management and fertilizer variation have significant influence on fluxes of CH4 emission from paddy fields. The difference of climatic conditions causes the interannual change of the flux of CH4 emission from paddy fields. In general, the flux of CH4 emission from paddy fields of flood irrigation is greater than that from paddy fields of discontinuous irrigation. To change the way of water management perhaps is an available way to reduce CH4 emission flux from paddy fields.

关键词： flux of CH4 emission paddy field changchun area influence factors

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AN ESTIMATION OF THE RANGING ACCURACY OF THE SLR SYSTEM AT changchun ARTIFICIAL SATELLITE STATION

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Chinese Science Bulletin 1990年第4期35卷 297-299页

作者：白葆林杨光陈海燕赵玉娟崔斗星杨福民谭德同陆文虎陈婉真 changchun Artificial Satellite Station Changchun 130117 PRC Shanghai Observatory Academia Sinica Shanghai 200030 PRC

The SLR system at changchun Artificial Satellite Station, which was developed by the station in cooperation with other institutes in China, went into test operation since June 1987. Successful laser ranging has been accomplished on satellites Lageos, Starlette and Ajisai. Ranging data of 18 satellite passes, which are typical of all the obtained data, were processed independently by changchun Station and Shanghai Observatory to estimate the ranging accuracy of single pulse for every individual satellite pass.

关键词： satellite laser ranging accuracy.

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GROUNDWATER QUALITY AND CONTAMINATION INDEX MAPPING IN changchun CITY,CHINA

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Chinese Geographical Science 2004年第1期14卷 63-70页

作者： Hamadoun BOKAR College of Environment and Resources Jilin UniversityChangchun 130026P.R.China

Groundwater in changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·Mg2+ or HCO3--Mg2+·Ca2+; SO42--Ca2+ and SO42--Ca2+·Mg2+; Cl--Ca2+; and CO32--Na+. The deteriorations of groundwater quality due to the increase of TDS, NO3-+ NO2-(as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca2+, Cl-and NO3-ions and weak negative correlations between the depth of water table and Ca2+, SO42-, Cl-and NO3-ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO3-, NO2-and Mn2+ ions.

关键词： hydrochemistry groundwater quality contaminant index linear regression analysis GIS mapping changchun City

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STUDY ON EUTROPHICATION CONTROL FOR SOUTH LAKE IN changchun

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Chinese Geographical Science 1995年第3期5卷 265-274页

作者：王海军王毅刘伟 Department of Environmental Science Northeast Normal University Changchun PRC

Although the mechanism of lake eutrophication is complicated,the basic factors are improper artificial activities and uncontrollable *** pollution sources were classified as primary and *** managing and controlling th... 详细信息

关键词： eutrophication comprehensive treatment channel engineering bioengineering substrata sludge deactivation

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