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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

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中国东北边境城市城镇化可持续发展过程及机制研究——以东宁和珲春市为例

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地理科学 2024年第3期44卷 474-482页

作者：丁月龙李晓玲刘鉴宋吉富贺红士东北师范大学地理科学学院吉林长春130024 东北师范大学长白山地理过程与生态安全教育部重点实验室吉林长春130024 东北师范大学中国东北研究院吉林长春130024 黑龙江省东宁市博物馆黑龙江东宁157200 密苏里大学自然资源学院美国密苏里州哥伦比亚65211

随着城镇化的快速发展,城市问题逐渐凸显,边境地区作为国家对外开放的重要门户,衡量其城镇化发展水平与可持续发展态势具有重要的理论与现实意义。本文以黑龙江省东宁市与吉林省珲春市为研究案例,从城市经济、口岸经济和社会状况3个维... 详细信息

随着城镇化的快速发展,城市问题逐渐凸显,边境地区作为国家对外开放的重要门户,衡量其城镇化发展水平与可持续发展态势具有重要的理论与现实意义。本文以黑龙江省东宁市与吉林省珲春市为研究案例,从城市经济、口岸经济和社会状况3个维度构建边境城市城镇化可持续发展综合指标体系,采用熵值法和改进麦肯锡矩阵评价边境城市城镇化发展水平以及城镇化可持续发展的综合表现与发展趋势,最后通过障碍度模型探究影响城镇化可持续发展的主要障碍因子。结果表明:①东宁和珲春总体城镇化发展水平呈上升趋势,主要受到城市经济与口岸经济发展水平的影响。②东宁和珲春总体城镇化可持续发展趋势与其城镇化发展过程是同步的,总体经历了低发展水平的可持续发展(1993-2005年)、发展水平不断提高的非可持续发展(2006-2016年)、中等发展水平的可持续发展(2017-2020年)3个阶段。③东宁与珲春城镇化可持续发展总体趋势相同,但受口岸经济发展水平的影响,在部分阶段呈现出一定的差异性特征。④城市经济是长期影响东宁和珲春城镇化可持续发展的主要障碍准则层,固定资产投资总额、一般公共预算支出、一般公共预算收入与出口依存度为主要障碍因子。研究结果可为边境城市城镇化可持续研究提供一定的理论与实证参考。

关键词：边境城市口岸经济新型城镇化麦肯锡矩阵障碍度模型

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The development process of a temperate montane peatland and its controlling factors since the middle Holocene

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Science China Earth Sciences 2023年第3期66卷 594-608页

作者： Yanmin DONG Hongkai LI Shengzhong WANG hongshi he Key Laboratory of Geographical Process and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration Northeast Normal UniversityChangchun 130024China School of Natural Resources University of MissouriMO 65211USA

Peatlands are some of the largest carbon reservoirs in terrestrial ecosystems and play a key role in the global carbon *** peatland development,carbon accumulation processes,and the peatland response to varying forcing factors over different temporal and spatial scales helps reveal the underlying processes and general patterns of these *** assess the role of climate and local conditions in peatland development,the basal samples from 23 peat cores and three well dated long peat cores were used to explore peatland initiation,lateral expansion,and carbon accumulation rate in the Baijianghe peatland located in the Changbai Mountains,Northeast *** results reveal that the Baijianghe peatland was initiated from forest conditions at 7.9 *** BP and then expanded laterally by *** rapid expansion between 5 and4 *** BP likely resulted from high precipitation and gentle *** mean carbon accumulation rates of the three long peat cores were 36.3,39.1 and 48.4 g C m^(-2)yr^(-1),respectively,which are higher than rates from the northern *** climate and local conditions have exerted an important influence on carbon accumulation rates in the Baijianghe peatland since the middle *** carbon accumulation patterns between 5 and 1.5 *** BP were probably linked to local conditions rather than climatic settings,including topography,hydrological conditions,and plant *** consistently decreasing carbon accumulation rate values at all locations within the BJH peatland over the last 1.5 *** BP suggests that climate is the primary *** study highlights the varying primary controls on the process of peatland development and reveals the important role of local conditions in carbon accumulation.

关键词： Paludification Peatland lateral expansion Carbon accumulation rate Northeast China Middle Holocene

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Detecting Global Vegetation Changes Using Mann-Kendal(MK) Trend Test for 1982–2015 Time Period

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Chinese Geographical Science 2018年第6期28卷 907-919页

作者： GUO Meng LI Jing he hongshi XU Jiawei JIN Yinghua School of Geographical Sciences Northeast Normal University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences School of Natural Resources University of Missouri-Columbia

Vegetation is the main component of the terrestrial ecosystem and plays a key role in global climate change. Remotely sensed vegetation indices are widely used to detect vegetation trends at large scales. To understand the trends of vegetation cover, this research examined the spatial-temporal trends of global vegetation by employing the normalized difference vegetation index(NDVI) from the Advanced Very High Resolution Radiometer(AVHRR) Global Inventory Modeling and Mapping Studies(GIMMS) time series(1982–2015). Ten samples were selected to test the temporal trend of NDVI, and the results show that in arid and semi-arid regions, NDVI showed a deceasing trend, while it showed a growing trend in other regions. Mann-Kendal(MK) trend test results indicate that 83.37% of NDVI pixels exhibited positive trends and that only 16.63% showed negative trends(P he period from 1982 to 2015. The increasing NDVI trends primarily occurred in tree-covered regions because of forest growth and re-growth and also because of vegetation succession after a forest disturbance. The increasing trend of the NDVI in cropland regions was primarily because of the increasing cropland area and the improvement in planting techniques. This research describes the spatial vegetation trends at a global scale over the past 30+ years, especially for different land cover types.

关键词： vegetation trend NDVI3g.v1 Mann-Kendall (MK) trend test land cover types

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Effective Seed Distribution Pattern of an Upward Shift Species in Alpine Tundra of Changbai Mountains

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Chinese Geographical Science 2016年第1期26卷 48-58页

作者： ZONG Shengwei XU Jiawei Eckart DEGE WU Zhengfang he hongshi School of Geographical Sciences Northeast Normal University Geography Institution Kiel University School of Natural Resources University of Missouri

The vegetation of alpine tundra in the Changbai Mountains has experienced great changes in recent decades. Narrowleaf small reed(Deyeuxia angustifolia), a perennial herb from the birch forest zone had crossed the tree line and invaded into the alpine tundra zone. To reveal the driven mechanism of D. angustifolia invasion, there is an urgent need to figure out the effective seed distribution pattern, which could tell us where the potential risk regions are and help us to interpret the invasion process. In this study, we focus on the locations of the seeds in the soil layer and mean to characterize the effective seed distribution pattern of D. angustifolia. The relationship between the environmental variables and the effective seed distribution pattern was also assessed by redundancy analysis. Results showed that seeds of D. angustifolia spread in the alpine tundra with a considerable number(mean value of 322 per m2). They were mainly distributed in the low elevation areas with no significant differences in different slope positions. Effective seed number(ESN) occurrences of D. angustifolia were different in various plant communities. Plant communities with lower canopy cover tended to have more seeds of D. angustifolia. Our research indicated reliable quantitative information on the extent to which habitats are susceptible to invasion.

关键词： plant invasion effective seed number (ESN) alpine tundra Changbai Mountains

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A Landscape Pattern Analysis Method Based on Boundaries and Nodes:A Case Study in Upper Minjiang River,China

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Chinese Geographical Science 2014年第1期24卷 50-59页

作者： WEN Qingchun LI Xiuzhen he hongshi HU Yuanman CheN Xin CHANG Yu WANG Wei BU Rencang Institute of Applied Ecology Chinese Academy of Sciences Liaoning Environmental Monitoring Center State Key Laboratory of Estuarine&Coastal Research East China Normal University University of Missouri-Columbia

Traditionally,patch-based analysis at the landscape scale fragmentation has been used in the study of landscape ecology while the study of boundary and node has not been considered as much detail until *** study investigated the possibility of applying boundary-and node-based methods in landscape pattern analysis to the upper reaches of the Minjiang River in the southwestern ***-based and node-based landscape indices were selected to be used in analyzing changes in landscape patterns,and the results were compared with analysis using traditional pattern *** compared the responses of patch-area-based,boundary-length-based and node-number-based indices,and concluded that boundary-based and node-based indices are more sensitive to disturbance than patch-based indices with various patterns,and node-based indices are even more sensitive than boundary-based ***,the results suggest that boundary-based and node-based pattern analysis methods provide helpful supplementary information to traditional patch-based pattern analysis *** results about pattern dynamics of landscapes in the upper reaches of the Minjiang River based on boundaries and nodes showed that with human disturbance,the dominance of forest landscape was weakened by other landscape types;thus the landscape pattern of the study area became more homogeneous and the boundary network became more *** changes further augmented disturbance interfaces in the landscape and increased the possibilities of further landscape fragmentation.

关键词： landscape pattern index patch boundary node Minjiang River

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Study on Forecast Scenarios for Simulation of Future Urban Growth in Shenyang City Based on SLEUTH Model

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Geo-Spatial Information Science 2010年第1期13卷 32-39页

作者： WU Xiaoqing HU Yuanman he hongshi XI Fengming BU Rencang Institute of Applied Ecology Chinese Academy of Sciences 72 Wenhua RoadShenyang 110016 China Yantai Institute of Coastal Zone Research Chinese Academy of Sciences 17 Chunhui Road Yantai 264003 China

The SLEUTH urban growth model was used to simulate future urban growth patterns and to explore potential environ-mental impacts of urban development under different conditions of development in Shenyang City, China. The SLEUTH model was calibrated with historical data (1988-2004) extracted from a time series of TM satellite images, and the future growth was pro-jected out to 2030 assuming three different policy scenarios: (1) current trends scenario (Scenario CT), (2) regional policy and ur-ban planning scenario (Scenario PP), and (3) environmental protection scenario (Scenario EP). Scenario analysis showed that urban growth would accelerate under all policy scenarios with significant differences in development pattern and sustainability after 2016. Urban development under Scenario CT would lead to substantial loss of resource lands than that under the other two scenarios, and the urban landscape pattern would be increasingly complex and dispersed. In contrast, urban growth under scenario PP and EP would consume less natural resource land and show a relatively compact urban development pattern during the prediction period. This study suggested that it is crucial to take stringent urban planning and management measures to control future urban growth and to protect primary farmland and the support system of urban ecology in Shenyang City. The SLEUTH model is a useful planning tool to guide sustainable utilization of urban land resources to a certain extent.

关键词： SLEUTH urban growth scenarios landscape pattern Shenyang City

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Comparative Assessment of Tundra Vegetation Changes Between North and Southwest Slopes of Changbai Mountains, China, in Response to Global Warming

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Chinese Geographical Science 2018年第4期28卷 665-679页

作者： JIN Yinghua ZHANG Yingjie XU Jiawei TAO Yan he hongshi GUO Meng WANG Ailin LIU Yuxia NIU Liping School of Geographical Sciences Northeast Normal University School of Natural Resources University of Missouri

Vegetation in high altitude areas normally exhibits the strongest response to global warming. We investigated the tundra vegetation on the Changbai Mountains and revealed the similarities and differences between the north and the southwest slopes of the Changbai Mountains in response to global warming. Our results were as follows: 1) The average temperatures in the growing season have increased from 1981 to 2015, the climate tendency rate was 0.38℃/10 yr, and there was no obvious change in precipitation observed. 2) The tundra vegetation of the Changbai Mountains has changed significantly over the last 30 years. Specifically, herbaceous plants have invaded into the tundra zone, and the proportion of herbaceous plants was larger than that of shrubs. Shrub tundra was transforming into shrub-grass tundra. 3) The tundra vegetation in the north and southwest slopes of the Changbai Mountains responded differently to global warming. The southwest slope showed a significantly higher degree of invasion from herbaceous plants and exhibited greater vegetation change than the north slope. 4) The species diversity of plant communities on the tundra zone of the north slope changed unimodally with altitude, while that on the tundra zone of the southwest slope decreased monotonously with altitude. Differences in the degree of invasion from herbaceous plants resulted in differences in species diversity patterns between the north and southwest slopes. Differences in local microclimate, plant community successional stage and soil fertility resulted in differential responses of tundra vegetation to global warming.

关键词： global warming Changbai Mountains tundra vegetation change species diversity patterns

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牦牛“海绵吸附”bta-miR-125b的lncRNA筛选验证及慢病毒载体构建

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畜牧与兽医 2024年第9期56卷 1-8页

作者：贺鸿世姚一龙索朗斯珠孟朝轶孔庆辉席广银郭敏徐业芬西藏农牧学院动物科学院西藏林芝860000 中国农业科学院深圳农业基因组研究所广东深圳518000 中国农业大学动物科学技术学院北京100193

旨在筛选在牦牛卵泡发育过程中可能吸附bta-miR-125b的长链非编码RNA(lncRNA),并构建双荧光素酶载体与慢病毒过表达载体,为研究调控牦牛生殖相关lncRNA的功能及机制提供基础。利用miRanda与RNAhybrid数据库预测可能靶向牦牛bta-miR-125b... 详细信息

旨在筛选在牦牛卵泡发育过程中可能吸附bta-miR-125b的长链非编码RNA(lncRNA),并构建双荧光素酶载体与慢病毒过表达载体,为研究调控牦牛生殖相关lncRNA的功能及机制提供基础。利用miRanda与RNAhybrid数据库预测可能靶向牦牛bta-miR-125b的lncRNAs,筛选出bta-miR-125b具有“海绵吸附”作用的lncRNAs,由RNAhybrid进行结合位点预测,筛选出最优的lncRNA;采集牦牛卵巢分离卵泡并提取总RNA构建cDNA池,以RT-PCR技术扩增筛选所得lncRNA;在此基础上利用pmir-GLO载体构建技术构建该lncRNA野生型及突变型双荧光素酶报告载体,并将其与bta-miR-125b mimics共转染至293T细胞,检测双荧光素酶活性;最后利用慢病毒载体构建技术将测序正确的lncRNA与pHBLV-CMV-MCS-EF1-ZsGreen-T2A-puro载体同源区的片段同源重组,通过慢病毒包装系统(psPAX2:pMD2G)包装后感染293T细胞,计算感染效率及滴度。结果:两个数据库中的lncRNA-ARS-UCD1.2与bta-miR-125b存在紧密结合位点,扩增出lncRNA-ARS-UCD1.2的序列全长为1552 bp;双荧光素酶活性检测表明牦牛lncRNA-ARS-UCD1.2与bta-miR-125b mimic具有靶向关系(P<0.01);同源重组后经酶切鉴定及测序验证表明成功构建了重组质粒,感染效率达(61.520±0.875)%,感染滴度为4×10^(8)TU/mL,表明lncRNA-ARS-UCD1.2过表达慢病毒载体成功构建。综上,本试验筛选出牦牛“海绵吸附”bta-miR-125b的lncRNA,并验证了两者的靶向结合关系,同时成功构建了该lncRNA的过表达慢病毒载体,为下一步深入研究lncRNA在细胞中的功能机制奠定了基础。

关键词：牦牛长链非编码RNA bta-miR-125b 海绵吸附慢病毒载体

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Soil Microbial Community and Enzyme Activity Responses to herbaceous Plant Expansion in the Changbai Mountains Tundra, China

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Chinese Geographical Science 2019年第6期29卷 985-1000页

作者： JIN Yinghua ZHANG Yingjie XU Zhiwei GU Xiaonan XU Jiawei TAO Yan he hongshi WANG Ailin LIU Yuxia NIU Liping 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 MissouriColumbiaMO 65211USA

As one of the most sensitive regions to global climate change, alpine tundra in many places around the world has been undergoing dramatic changes in vegetation communities over the past few *** plant species in the Changbai Mountains area have significantly expanded into tundra shrub communities over the past 30 *** microbial communities, enzyme activities, and soil nutrients are intertwined with this expansion *** order to understand the responses of the soil microbial communities to such an expansion, we analyzed soil microbial community structures and enzyme activities in shrub tundra as well as areas with three different levels of herbaceous plant *** investigation was based on phospholipid fatty acid(PLFA) analysis and 96-well microtiter *** results showed that herbs have expanded greatly in the tundra, and they have become the dominant species in herbaceous plant expansion *** were differences for community composition and appearance among the shrub tundra and the mild expansion, moderate expansion, and severe expansion *** for soil organic matter, soil nutrients were increased in herbaceous plant expansion areas, and the total nitrogen(TN), total phosphorus(TP), available nitrogen(AN), and available phosphorus(AP) were greatest in moderate expansion areas(MOE), while soil organic matter levels were highest in the non-expanded areas(CK).The total soil PLFAs in the three levels of herbaceous plant expansion areas were significantly higher than those in the non-expanded areas, and total soil PLFAs were highest in the moderately expanded area and lowest in the severely expanded area(SEE).Bacteria increased significantly more than fungi and actinomycetes with herbaceous plant *** hydrolase activities(β-1,4-glucosidase(βG) activity, β-1, 4-N-acetylglucosaminidase(NAG) activity, and acid phosphatase(aP) activity) were highest in MOE and lowest in the CK *** oxidase activities(polypheno

关键词： Changbai Mountains tundra herbaceous plant expansion soil microorganism soil enzyme activity soil nutrients

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