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Quantitative relationships between vegetation and several pollen taxa in surface soil from North china

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Chinese science Bulletin 2000年第16期45卷 1519-1523页

作者： li Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and environmental sciences, Peking university, Beijing 100871, china 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of sciences, Beijing 100093, china 3. school of urban and environmental sciences, northeast normal university, changchun 130024, china Correspondence should be addressed to li Yiyin Department of Urbon and environmental sciences Peking University Beijing China school of urban and environmental sciences Northeast Normal University Changchun China Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the northeast china Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept

关键词： pollen taxa in surface soil vegetation regression parameters (slope term and y-intercept term) representation northeast china Transect (NECT).

Current Situation,Problems and Countermeasures of World Heritage Protection in china

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china City Planning Review 2012年第3期21卷 8-17页

作者： li Rusheng SHI Ke PhD,school of urban and environmental science,northeast normal university,changchun,P.R.china.

The development of World Heritage protection in china can be characterized by four facts,which are the increasing number,the domination of cultural heritages,the uneven spatial distribution,and the abundant candidate reserve for ***,the problems of the dislocation of understanding,the absence of planning,the disorder of management,the lack of relevant institutions still exist in the field of World Heritage protection,aiming at which,the author puts forward some countermeasures,such as completing legislation system,carrying out scientific planning,implementing hierarchical and assorted administration,strengthening supervision,increasing investments,and enhancing propaganda and education.

关键词： World Heritage problem countermeasure

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长白山红松、水曲柳的能量与物质分析

山地学报 2002年第2期20卷 241-245页

作者：张郁秦丽杰吴东辉周密东北师范大学城市与环境科学学院吉林大学地球科学学院东北师范大学城市与环境科学学院吉林长春130024 吉林长春130061

通过对长白山地区典型样地的调查、测定和分析 ,以红松、水曲柳为代表树种 ,对其进行了能量与物质研究 ,得出红松和水曲柳的化学能模型以及物质含量变化图 ,从而为揭示森林生态系统中物质与能量的运动规律提供了科学依据

关键词：化学能物质含量红松水曲柳

Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

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Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong Na li Mai-He li Yu Cong Haibo Du Decai Gao Hong S.He Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China school of Natural Resources University of MissouriColumbiaMO65211USA Swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China school of life science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TSAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TSALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NSC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TSAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TSAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TSAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TSAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NSC) Non-treeline species Sink activity Stressful environments Upper elevation limit

Neighbour effects on plant biomass and its allocation for forbs growing in heterogeneous soils

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Journal of Plant Ecology 2024年第4期17卷 90-99页

作者： Yongjie liu Chunyan Ma Shiting liu Mingrui liu Hui li Mingxia Wang Guoe li Hans J.De Boeck Fujiang Hou Zhanhui Tang Zhenxin li State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020China school of Ecology and environmental sciences Yunnan UniversityKunming 650091China Plant and Ecosystems(PLECO) Department of BiologyUniversity of AntwerpWilrijk B-2610Belgium State environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration School of EnvironmentNortheast Normal UniversityChangchun 130117China Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau Ministry of EducationLhasa 850011China

Focal plants are considerably affected by their neighbouring plants,especially when growing in heterogeneous soils.A previous study on grasses demonstrated that soil heterogeneity and species composition affected plant biomass and above-and belowground allocation *** now tested whether these findings were similar for *** forb species(*** anglica,limonium bicolor and Suaeda glauca)were grown in pots with three levels of soil heterogeneity,created by alternatively filling resource-rich and resource-poor substrates using small,medium or large patch *** compositions were created by growing these forbs either in monocultures or in *** showed that patch size×species composition significantly impacted shoot biomass,root biomass and total biomass of forbs at different ***,at the pot scale,shoot biomass,root biomass and total biomass increased with increasing patch *** the substrate scale,shoot biomass and total biomass were higher at the large patch size than at the medium patch size,both in resource-rich and resource-poor ***,at the community scale,monocultures had more shoot biomass,root biomass and total biomass than those in the two-or three-species *** results differ from earlier findings on the responses of grasses,where shoot biomass and total biomass decreased with patch size,and more shoot biomass and total biomass were found in resource-rich than resource-poor *** further elucidate the effects of soil heterogeneity on the interactions between neighbour plants,we advise to conduct longer-term experiments featuring a variety of functional groups.

关键词： biomass allocation neighbour effect patch size soil heterogeneity shoot biomass

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长白山自然保护区生态旅游SWOT分析

生态经济(学术版) 2008年第1期 306-309页

作者：李勇王金伟佟连军东北师范大学城市与环境科学学院东北师范大学历史文化学院中国科学院东北地理与农业生态研究所长春130024 长春130012

以吉林省长白山自然保护区为研究对象,文章运用SWOT分析方法,分析了长白山自然保护区生态旅游的优势、劣势、机遇与挑战,并据此对长白山自然保护区开展生态旅游提出了具体对策。

关键词： SWOT分析长白山自然保护区生态旅游

Centennial Analysis of Human Activity Intensity and Associated Historical Events in Heilongjiang River Sino-Russo Watershed

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Chinese Geographical science 2024年第2期34卷 280-293页

作者： SONG Chaoxue li Xiaoling HE Hongshi Michael SUNDE school of Geographical sciences Northeast Normal UniversityChangchun 130024China school of Natural Resources University of MissouriColumbia 65211USA

Human activities in a transborder watershed are complex under the influence of domestic policies,international relations,and global *** the forces driving human activity change is important for the development of transborder *** this study,we used global historical land cover data,the hemeroby index model,and synthesized major historical events to analyze how human activity intensity changed in the Heilongjiang River(Amur River in Russia)watershed(HLRW).The results showed that there was a strong spatial heterogeneity in the variation of human activity intensity in the HLRW over the past century(1900-2016).On the Chinese side,the human activity intensity change shifted from the plain areas for agricultural reclamation to the mountainous areas for timber *** the Russian side,human activity intensity changes mostly concentrated along the Trans-Siberian Railway and the Baikal-Amur *** variation of human activity intensity tended to respond to regional events while regionalized variation tends to reflect national policy change or broad international *** similarities and differences between china and Russia in policies and positions in international events resulted in synchronous and asynchronous changes in human activity ***,policy shifts were often confined by the natural features of the *** results reveal the historical origins and fundamental connotations of watershed development and contribute to formulating regional management policies that coordinate population,eco-nomic,social,and environmental activities.

关键词： human activity intensity changes hemeroby index centennial scale Heilongjiang River(Amur River in Russia)watershed china Russia

Recent progress in CdS-based S-scheme photocatalysts

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Journal of Materials science & Technology 2024年第4期171卷 162-184页

作者： Yajing Ren Yunfeng li Guixu Pan Ning Wang Yan Xing Zhenyi Zhang College of environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China Jilin Provincial Key Laboratory of Advanced Energy Materials Department of ChemistryNortheast Normal UniversityChangchun 130024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further *** sulfide(CdS),as a typical reducing semiconductor of metal sulfides,represents an interesting research hotspot in photocatalysis due to its suitable bandgap(2.4 eV)for utilizing visible light and strong reducing ability for inducing surface catalytic ***,the photocatalytic performance of CdS is still limited by its fast carrier recombination and serious *** far,CdS semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel S-scheme heterojunction to overcome the above *** this review,the de-sign concepts,basic principles,and charge transfer characteristics of CdS-based S-scheme heterojunction photocatalysts have been comprehensively *** advanced and effective characterization methods for studying the mechanism of CdS-based S-scheme heterojunction are analyzed in ***-thermore,we also summarize the typical applications of CdS-based S-scheme heterojunctions for water splitting,CO_(2) reduction,pollutant degradation,***,according to the current investigation sta-tus,some drawbacks in the current synthetic strategy,mechanism exploration,and application prospect of CdS-based S-scheme heterojunction are proposed,which need to be addressed by further expansion and innovative research.

关键词： Photocatalysis CdS semiconductor Heterojunction S-scheme Metal sulfide

Molecular crowding electrolytes for stabilizing Zn metal anode in rechargeable aqueous batteries

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Chinese Chemical Letters 2024年第7期35卷 445-451页

作者： li lin Song-lin Tian Zhen-Yu Hu Yu Zhang li-Min Chang Jia-Jun Wang Wan-Qiang liu Qing-Shuang Wang Fang Wang school of Materials science and Engineering Changchun University of Science and TechnologyChangchun 130022China school of life science and Technology Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Preparation and Applications of environmental Friendly Materials of the Ministry of Education Jilin Normal UniversityChangchun 130103China Zhongshan Institute of changchun university of science and Technology Zhongshan 528437China

A solid electrolyte interphase(SEI)with a robust mechanical property and a high ionic conductivity is imperative for high-performance zinc metal ***,it is difficult to form such a SEI directly from an *** this work,a molecular crowding effect is based on the introduction of Zn(OTF)_(2)and Zn(ClO_(4))_(2)to 2 mol/L ZnSO_(4)*** and experiments indicate that the Zn(OTF)_(2)and Zn(ClO_(4))_(2)not only create a molecularly crowded electrolyte environment to promote the interaction of Zn^(2+)and OTF^(-),but also participate in the reduction to construct a robust and high ionic-conductive SEI,thus promoting metal zinc deposition to the(002)crystal *** this molecular crowding electrolyte,a high current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn as the anode for over 1000 *** in a temperature environment of-10℃,a current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn for over 200 ***//Bi_(2)S_(3)/VS4@C cells achieve a CE rate of up to 99.81%over 1000 ***,the utilization of a molecular crowding electrolyte is deemed a highly effective approach to fabricating a sophisticated SEI for a zinc anode.

关键词： Zinc ion batteries Anode Electrolyte Solid electrolyte interphase Molecular crowding effect