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Characteristics of timberline and treeline altitudinal distribution in *** and their geographical interpretation

Journal of Mountain Science 2022年第10期19卷 2846-2860页

作者： MU Hao-xiang HAN Fang ZHANG Bai-ping LIANG Tian WANG Zhi-yong WANG Zhe School of Civil and Architectural Engineering Shandong University of TechnologyZibo 255000China State Key Lab for Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Center for Yellow River Ecosystem Products Shandong UniversityQingdao 266237China

Different types of vegetation patches are alternately and randomly distributed in a timberline ecotone where the upper limit is the treeline and the lower limit is the ***,most studies on timberline/treeline altitudinal distributions have simplified timberline or treeline as continuous curves and disregarded the fuzziness of timberline/treeline and the randomness of different vegetation patch distributions in a timberline *** study the altitudinal distribution characteristics of timberline and treeline from the perspective of uncertainty theory,we constructed the timberline and treeline elevation cloud models in *** in east ***,we established multiple linear regression models by using nine influencing factors,namely,aspect,slope,topographic relief,dryness index,average temperature in January and July,latitude,summit syndrome(represented by the vertical distance from the peak),and snow effect(represented by the nearest distance from the snow)as independent variables,and the elevations of timberline/treeline as dependent *** we compared the contributions of the nine factors in timberline,treeline,and the core and peripheral areas of timberline and *** results show that 1)the timberline/treeline elevation cloud model can represent the overall characteristics(especially the uncertainty)of the altitudinal distributions of the timberline/treeline *** uncertainty of treeline’s altitudinal distribution is higher than that of timberline(entropy and hyper entropy:207.59 m and 70.36 m for treeline elevation cloud;entropy and hyper entropy:191.17 m and 50.13 m for timberline elevation cloud).2)The influence of climate and topography on timberline and treeline are *** average temperature in July has a significant negative correlation with the timberline/treeline elevation in ***,which is the most critical factor that affects timberline and treeline elevation,explaining the altitudinal

关键词： timberline Treeline Geographical interpretation Uncertainty Influencing factors Mt.Namjagbarwa

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Immediate responses of forest-floor bryophyte assemblage to patched clear-cutting in primary spruce forest nearby alpine timberline

Immediate responses of forest-floor bryophyte assemblage to ...

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2012年全国苔藓植物学学术研讨会

作者： Xin Liu Wei-Kai Bao Chengdu Institute of Biology Chinese Academy of Sciences Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization Chinese Academy of Sciences Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province

In order to understand the responses of bryophytes composition and diversity to patched clear-cut, BACI methodology were used to investigate site-to-site and year-to-year variability. We investigated 6 40×50m 2 permanent plots and 3 of them were harvested afterwards. The results showed that 141 taxa of bryophytes were identified from the 6 plots;cover of bryophytes decreased greatly after harvest, while cover of litter increased greatly;almost all of the bryophytes were declined in frequency of occurrence;no significant difference were shown in the decreasing rate of morphological groups and life forms, but still liverworts was the most sensitive group to harvest;10 of 16 liverworts, 8 of 37 peurocarpous mosses and 8 of 44 acrocarpous mosses were completely disappeared;species richness and Shannon-Wiener’ index of biodiversity were decreased significantly post-harvest. Our results suggest that bryophytes species response rapidly to clear-cut, direct effect of harvest may be the main reason. Due to time lag, indirect changes in microclimate may take effect later. We also provide suggestion for bryophytes conservation in retention patches and cutovers.

关键词： Primary Spruce Forest timberline Bryophyte Biological Conversation

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The Distribution Patterns of timberline and Its Response to Climate Change in the Himalayas

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Journal of Resources and Ecology 2020年第4期11卷 342-348页

作者： SHI Peili WU Ning Gopal SRAWAT Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China Wildlife Institute of India Dehradun 248001UttaranchalIndia

Himalayan region represents the highest and most diverse treeline over the *** one of the most conspicuous boundaries between montane forests and alpine vegetation,the alpine timberline attracted the interest of researchers for many ***,timberline in the Himalayas is understudied compared with European counterparts due to *** we review the distribution pattern of timberline and its climatic condition,the carbon and nutrient supply mechanism for treeline formation,and treeline shift and treeline tree recruitment under climate change *** limitation,rather than carbon source limitation is the physiological cause of timberline under the low temperature *** limitation and water stress are not the direct cause of timberline ***,more clear local limitation factors are need to integrate in order to enable us to predict the potential impacts and changes caused by human activity and related global change in this sensitive region.

关键词： timberline treeline ecotone floristic and species composition carbon and nutrient relation climate change timberline shift

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学习国外先进技术提升企业信息化管理水平——对美国“timberline管理软件”的思考

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中国建设信息化 2003年第3期 28-31页

作者：李燕凌中国建筑一局(集团)有限公司

为学习国外先进的软件管理技术,提升我国施工企业信息化管理水平,最近,中建一局(集团)公司牵头组织了局机关部门和下属公司人员赴澳大利亚,对美国“timberline”软件公司的管理软件进行了考察和交流。通过考察和交流,更清楚地看到了我... 详细信息

为学习国外先进的软件管理技术,提升我国施工企业信息化管理水平,最近,中建一局(集团)公司牵头组织了局机关部门和下属公司人员赴澳大利亚,对美国“timberline”软件公司的管理软件进行了考察和交流。通过考察和交流,更清楚地看到了我们与国外企业信息化管理的差距。

关键词：企业信息化管理 timberline 项目成本控制软件分包商财务管理系统中建一局分供美国美利坚合众国北美洲

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Critical minimum temperature limits xylogenesis and maintains treelines on the southeastern Tibetan Plateau

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Science Bulletin 2017年第11期62卷 804-812页

作者： Xiaoxia Li Eryuan Liang Jozica Gricar Sergio Rossi Katarina Cufar Aaron M. Ellison Key Laboratory of Alpine Ecology and Biodiversity Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100101 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China Sloven ian Forestry Institute Department of Yield and Silviculture Vecna pot 2 S1-1000 Ljubljana Slovenia University of Quebec in Chicoutimi Departement des Sciences Fondamentales 555 Boulevard de l'Universite Chicoutimi (QC) G7H2B1 Canada Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems Guangdong Provincial Key Laboratory of Applied Botany South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China University of Ljubljana Biotechnical Faculty Department of Wood Science and Technology Jamnikarjeva 101 S1-1000 Ljubljana Slovenia Harvard Forest Harvard University 324 North Main St. Petersham MA 01366 USA

Physiological and ecological mechanisms that define treelines are still debated. It has been suggested that the absence of trees above the treeline is caused by low temperatures that limit growth. Thus, we hypothesized that there is a critical minimum temperature （CTmin） preventing xylogenesis at treeline. We tested this hypothesis by examining weekly xylogenesis across three and four growing seasons in two natural Smith fir （Abies georgei var. srnithii） treeline sites on the southeastern Tibetan Plateau. Despite differences in the timing of cell differentiation among years, minimum air temperature was the dominant climatic variable associated with xylem growth; the critical minimum temperature （CTmin） for the onset and end of xylogenesis occurred at 0.7 ±0.4 ℃. A process-based modelling chronology of tree-ring formation using this CTmin was consistent with actual tree-ring data. This extremely low CTmin permits Smith fir growing at treeline to complete annual xylem production and maturation and provides both support and a mechanism for treeline formation.

关键词： Cambial activity Critical minimum temperature timberline Xylem Vaganov-Shashldn model

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Tree clusters migration into alpine tundra,Siberia

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Journal of Mountain Science 2022年第12期19卷 3426-3440页

作者： KHARUK Viacheslav I. PETROV II'ya A. IM Sergei T. GOLYUKOV Alexey S. DVINSKAYA Maria L. SHUSHPANOV Alexander S. Sukacheu Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk 660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk 660041Russia Reshetneu Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 66014Russia Tomsk State University Leninastr.36Tomsk 634050Russia

We hypothesize that in mountain windy habitat trees formed clusters(hedges)as adaptive structures for seedlings’rooting,survival,and tress’upslope *** studied hedges formed by Siberian pine(Pinus sibirica du Tour)and larch(Larix sibirica Ledeb.)within the treeline ecotone in southern Siberian Mountains,investigated hedges formation,evolution,habitat amelioration,and analyzed tree’s growth index(GI)dependence on the eco-climate variables(air temperature,precipitation,soil moisture,wind speed)and relief features(elevation,aspect,slope steepness,and terrain curvature).We conducted a ground survey,measured biometrical parameters of trees and hedges,determined species composition and tree physiognomy,soil types and nutrient contents,and sampled wood cores and applied dendrochronology for trees’GI *** high-resolution satellite scenes for hedge detection and upslope migration,we found that winter winds and soil moisture are the main constraints of trees’settlement and *** formation always links with wind-sheltered microtopography features(boulders,local depressions or felled trees).Once the first tree is established,a positive feedback is aroused that facilitates seedling rooting and in-hedge habitat *** form a streamlined dense“common crown”that mitigates adverse winter wind *** always orient along the prevailing winds,and trees’uphill migration occurs by seedlings establishment within the leeward hedge *** growth facilitates soil formation and *** concentration of nutrients(K,P,N and S)within hedges exceeds the background by 1.5-5.5 *** extension leads to increased snow accumulation that mitigates the influence of desiccation and snow abrasion and mitigates seasonal water *** the extremely harsh windy habitat,inhedge trees present in mat,prostrate or krummholz *** warming,tree stems and even twigs turn *** that GI dependence on the wind speed is insignificant unt

关键词： Treeline timberline Hedges Tree migration Siberian pine Larch Tree growth Siberian mountain forests Wind stress Moisture stress

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Morphological Characteristics and Environmental Implications of Phytoliths in Topsoils from Different Vegetation Zones on Northern Slope of Changbai Mountains,China

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Chinese Geographical Science 2010年第6期20卷 506-512页

作者： QIAO Zhihe JIE Dongmei LIU Hongmei GE Yong ZHANG Hongyan College of Urban and Environmental Science Northeast Normal UniversityChangchun 130024China Daqing Normal University Daqing 163001China

The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global *** this study,the topsoils were collected from different vertical vegetation zones on the northern slope of the Changbai Mountains,Northeast China in August 2009,and phytoliths in the soil samples were extracted by using wet oxidation method and identified with Motic 2.0 microscope in *** results show that phytoliths are abundant in the topsoils of the study *** herbal phytoliths are primarily composed of elongated,tooth-shaped,point-shaped and hat-shaped phytoliths,as well as a small amount of fan-shaped and square-shaped *** elongated,tooth-shaped,point-shaped and hat-shaped phytoliths are representative of cold climate,while fan-shaped and square-shaped ones are representative of warm and humid *** the conifer broadleaved mixed forest zone,coniferous forest zone and broadleaf forest zone,there are close correlations between vegetation and woody phytoliths in the topsoils,indicating that the woody plants of a region can be reconstructed from the woody phytolith assemblages in the ***,the topsoil phytolith assemblages can also be used to reconstruct the understory herbs *** phytolith assemblages in the topsoils of the forest community and herbal community differ significantly,which can help indicate the historical location of the timberline.

关键词： topsoil phytolith timberline environmental implication vertical vegetation zones Changbai Mountains

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Magnitude and Forming Factors of Mass Elevation Effect on Qinghai-Tibet Plateau

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Chinese Geographical Science 2016年第6期26卷 745-754页

作者： ZHANG Shuo ZHANG Baiping YAO Yonghui ZHAO Fang QI Wenwen HE Wenhui WANG Jing State Key Laboratory of Resource and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Mass elevation effect （MEE） refers to the thermal effect of huge mountains or plateaus, which causes the tendency for tem- perature-related montane landscape limits to occur at higher elevations in the inner massifs than on their outer margins. MEE has been widely identified in all large mountains, but how it could be measured and what its main forming-factors are still remain open. This paper, supposing that the local mountain base elevation （MBE） is the main factor of MEE, takes the Qinghai-Tibet Plateau （QTP） as the study area, defines MEE as the temperature difference （AT） between the inner and outer parts of mountain massifs, identifies the main forming factors, and analyzes their contributions to MEE. A total of 73 mountain bases were identified, ranging from 708 m to 5081 m and increasing from the edges to the central parts of the plateau. Climate data （1981-2010） from 134 meteorological stations were used to acquire ATby comparing near-surface air temperature on the main plateau with the free-air temperature at the same altitude and simi- lar latitude outside of the plateau. The AT for the warmest month is averagely 6.15 ~C, over 12~C at Lhatse and Baxoi. A multivariate linear regression model was developed to simulate MEE based on three variables （latitude, annual mean precipitation and MBE）, which are all significantly correlated to AT. The model could explain 67.3% of MEE variation, and the contribution rates of three independent variables to MEE are 35.29%, 22.69% and 42.02%, respectively. This confirms that MBE is the main factor of MEE. The intensive MEE of the QTP pushes the 10~C isotherm of the warmest month mean temperature 1300-2000 m higher in the main plateau than in the outer regions, leading the occurrence of the highest timberline （4900 m） and the highest snowline （6200 m） of the Northern Hemisphere in the southeast and southwest of the plateau, respectively.

关键词： Qinghai-Tibet Plateau mass elevation effect (MEE) temperature difference mountain base elevation timberline

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Detecting treeline dynamics in response to climate warming using forest stand maps and Landsat data in a temperate forest

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Forest Ecosystems 2018年第3期5卷 311-324页

作者： Maliheh Arekhi Ahmet Yesil Ulas Yunus Ozkan Fusun Balik Sanli Institutes of Graduate Studies in Science and Enclineering Forest Ena neer haIstanbul University34452 IstanbulTurkey Faculty of Forestry Department or Forest ManagementIstanbul University34473 IstanbulTurkey Faculty of Civil Engineering Department of Geomatic EngineeringYlldlz Technical University34220 IstanbulTurkey

Background: Treeline dynamics have inevitable impacts on the forest treeline structure and composition. The present research sought to estimate treeline movement and structural shifts in response to recent warming in Cehennemdere, Turkey. After implementing an atmospheric correction, the geo-shifting of images was performed to match images together for a per pixel trend analysis. We developed a new approach based on the NDVI, LST(land surface temperature) data, air temperature data, and forest stand maps for a 43-year period. The forest treeline border was mapped on the forest stand maps for 1970, 1992, 2002, and 2013 to identify shifts in the treeline altitudes, and then profile statistics were calculated for each period. Twenty sample plots(10 × 10 pixels) were selected to estimatethe NDVI and LST shifts across the forest timberline using per-pixel trend analysis and non-parametric Spearman’s correlation analysis. In addition, the spatial and temporal shifts in treeline tree species were computed within the selected plots for four time periods on the forest stand maps to determine the pioneer tree ***: A statistically significant increasing trend in all climate variables was observed, with the highest slopein the monthly average mean July temperature(tau = 0.62, ρ < 0.00). The resultant forest stand maps showed a geographical expansion of the treeline in both the highest altitudes(22 m–45 m) and the lowest altitudes(20 m–105 m) from 1970 to 2013. The per pixel trend analysis indicated an increasing trend in the NDVI and LST values within the selected plots. Moreover, increases in the LST were highly correlated with increases in the NDVIbetween 1984 and 2017(r = 0.75, ρ < 0.05). Cedrus libani and Juniperus communis app. were two pioneer tree species that expanded and grew consistently on open lands, primarily on rocks and soil-covered areas, from 1970 to ***: The present study il ustrated that forest treeline dynamics and treeline structural

关键词： NDVI Geoshift LST timberline Mann-Kendall Landsat Climate warming

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Larch growth across thermal and moisture gradients in the Siberian Mountains

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Journal of Mountain Science 2023年第1期20卷 101-114页

作者： KHARUK Viacheslav I. PETROV Il'ya A. GOLYUKOV Alexey S. DVINSKAYA Maria L. IM Sergei T. SHUSHPANOV Alexander S. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014Russia Tomsk State University Lenina str.36Tomsk634050Russia

Climate-driven changes in the thermal and moisture regimes may variously influence different tree species growth and *** hypothesize that drought resistant Siberian larch(Larix sibirica Ledeb.)and precipitation-sensitive Siberian pine(Pinus sibirica Du Tour)responded differently to climate change along the elevational thermal and precipitation *** studied the influence of air temperature,precipitation,soil moisture,and atmospheric drought(indicated by the drought index SPEI)on larch and pine growth along the southward megaslope of the West Sayan *** found that since 2000 climate change resulted in increasing larch and pine radial growth index(GI)(c.1.5–3times)within treeline(2000–2300 m)and timberline(1900–2000 m)ecotones,*** high precipitation *** the forest-steppe ecotone(1100–1200 m)in which *** is the only species,larch GI stagnated or even *** total forested area increased since 2000 up to+50%in the high elevations,whereas in the low elevations(timberline,trees’GI was stimulated by summer ***,temperature increase in early spring reduces GI due to living tissue activation followed by tissue damage by *** forest-steppe,larch radial growth was mostly dependent on soil *** shifted dependence on moisture to the early dates of the growing *** droughts decreased GI within forest-steppe as well as within treeline,whereas the drought influence on both species within highlands was *** forest-steppe seedlings establishment was poor,whereas it was successful within treeline and *** climate change leads to stagnation or even decrease in Larix sibirica growth in the southern lowland *** combination with poor seedlings establishment,reduced growth threatens the transformation of open lowland forests into forest-steppe and steppe ***,in the highlands warming

关键词： Larch Siberian pine Climate influence on tree radial growth Mountain forests Treeline timberline Foreststeppe Drought stress Moisture stress

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