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Tree species diversity and stand structure along major community types in lowland primary and secondary moist deciduous forests in Tripura,Northeast India

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Journal of Forestry Research 2012年第4期23卷 553-568页

作者： Koushik Majumdar Uma Shankar Badal Kumar Datta Plant Taxonomy and Biodiversity Laboratory Department of BotanyTripura UniversitySuryamaninagar-799130TripuraIndia ecosystem Research Laboratory Centre for Advanced Studies in BotanySchool of Life ScienceNorth-Eastern Hill UniversityShillong-793022MeghalayaIndia

Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging to 46 family, 103 genera and 144 species were counted at ≥30 cm DBH （diameter at breast height） using 28 permanent belt transects with a size of 1 ha （10 m × 1000 m）. Four different tree communities were identified. The primary forests was dominated by Shorea robusta （mean density 464.77 ***^-1, 105 species） and Schima wallichii （336.25 ***^-1, 82 species）, while the secondary forests was dominated by Tectona grandis （333.88 ***^-1, 105 species） and Hevea brasiliensis （299.67 ***^-1, 82 species）. Overall mean basal area in this study was ***^-1; the maximum value was recorded in primary Shorea forest （26.21 ***^-1）. Mean density and diversity indices were differed significantly within four different communities. No significant differences were observed in number of species, genera, family and tree basal cover area. Significant relationships were found between the species richness and different tree population groups across the communities. Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumu- lation of native oligarchic small tree species. Seventeen species were recorded with 〈2 individuals of which Saraca asoka （Roxb.） de Wilde and Entada phaseoloides （L.） Men＇. etc. extensively used in local ethnomedicinal formulations. The present S. robusta Gaertn dominated forest was recorded richer （105 species） than other reported studies. Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests. Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur. The analysis of FIV suggested a slow trend of shifting the p

关键词： diversity and stand structure moist deciduous forest species conservation tree community types

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Impact of forcing data and land surface properties on snow simulation in a regional climate model:a case study over the Tianshan mountains,Central Asia

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Journal of mountain Science 2021年第12期18卷 3147-3164页

作者： LI Qian YANG Tao LI Lan-hai State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Ili Station for Watershed ecosystem Research Chinese Academy of SciencesXinyuan 835800China Key Laboratory for mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China CAS Research centre for Ecology and Environment of Central Asia Urumqi 830011China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China

Snow is a key variable that influences hydrological and climatic *** surface models employing snow physics-modules can simulate the snow accumulation and ablation ***,there are still uncertainties in modeling snow resources over complex terrain such as *** study employed the National Center for Atmospheric Research’s Weather Research and Forecasting(WRF)model coupled with the Noah-Multiparameterization(Noah-MP)land surface model to run one-year simulations to assess its ability to simulate snow across the Tianshan *** tests were conducted based on different reanalysis forcing datasets and different land surface *** results indicated that the snow dynamics were reproduced in a snow hydrological year by the WRF/Noah-MP model for all of the *** model produced a low bias in snow depth and snow water equivalent(SWE)regardless of the forcing ***,the underestimation of snow depth and SWE could be relatively alleviated by modifying the land cover and vegetation ***,no significant improvement in accuracy was found in the date of snow depth maximum and melt *** best performance was achieved using ERA5 with modified land cover and vegetation parameters(mean bias=−4.03 mm and−1.441 mm for snow depth and SWE,respectively).This study highlights the importance of selecting forcing data for snow simulation over the Tianshan mountains.

关键词： WRF/Noah-MP model Initial and lateral boundary conditions Land surface properties Snow depth Snow water equivalent

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Biomass and net primary productivity of mangrove communities along the Oligohaline zone of Sundarbans, Bangladesh

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Forest ecosystems 2017年第4期4卷 264-272页

作者： Md. Kamruzzaman Shamim Ahmed Akira Osawa Laboratory of ecosystem Production and Dynamics Graduate School of Global Environmental Studies Kyoto University Kyoto 606-8501 Japan Forestry and Wood Technology Discipline Khulna University Khulna 9208 Bangladesh

Background： The article presents the first estimates of biomass and productivity for mangrove forests along the Oligohaline zone of the Sundarbans Reserve Forest （SRF）, Bangladesh. This study was conducted overone year from March 2016 to April 20] 7. Stand structure, above and below-ground biomass changes, and litterfall production were measured within a 2100 m2 sample plot. Methods： All trees in the study plots were numbered and height （H） and diameter at breast height （DBH） were measured. Tree height （H） and DBH for each tree were measured in March 2016 and 2017. We apply the above and belowground biomass equation for estimating the biomass of the mangrove tree species （Chave et al. Oecologia 145：87-99, 2005; Komiyama et al. J Trop Ecol 21：471-477, 2005）. Litterfall was collected using 1-mm mesh litter traps with collection area of 0.42 m2. Net Primary Production （NPP） was estimated by the summation method of Ogawa Primary productivity of Japanese forests： productivity of terrestrial communities, JIBP synthesis （1977） and Matsuura and Kajimoto Carbon dynamics of terrestrial ecosystem： Systems approach to global environment （2013）. Results： Heritiero fomes has maintained its dominance of the stand and also suffered the highest tree mortality （2.4%） in the suppressed crown class. The total above-ground biomass （AGB） and below-ground biomass （BGB） of the studied stand was ]54.8 and 84.2 ***-1, respectively. Among the total biomass of the trees, 64.8% was allocated to AGB and 35.2% to BGB. In case of species-wise contribution of biomass allocation, Avicennia officinalis showed the highest score and Aglaia cucullota the lowest. Mean annual total litterfall was 10.1 Mg-ha ***-1, with the maximum litterfall in winter or dry season and late summer or rainy season. The mean AGB increment and above-ground net primary productivity （AGNPP） were 7.1 and 17.2 ***-1, respectively. Total net primary productivity （NPP） was estimated to be 21.0 *** Lyr-1 over the observ

关键词： Primary production Litterfall Monthly pattern Biomass carbon Species wise contribution Sundarbans

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γδT cells:Major advances in basic and clinical research in tumor immunotherapy

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Chinese Medical Journal 2024年第1期137卷 21-33页

作者： Yueqi Zhao Peng Dong Wei He Jianmin Zhang Hui Chen Department of Immunology CAMS Key Laboratory for T Cell and ImmunotherapyState Key Laboratory of Medical Molecular BiologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences and School of Basic MedicinePeking Union Medical CollegeBeijing 100005China Changzhou Xitaihu Institute for Frontier Technology of Cell Therapy ChangzhouJiangsu 213000China Haihe Laboratory of Cell ecosystem Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300020China

γδT cells are a kind of innate immune T *** have not attracted sufficient attention because they account for only a small proportion of all immune cells,and many basic factors related to these cells remain ***,in recent years,with the rapid development of tumor immunotherapy,γδT cells have attracted increasing attention because of their ability to exert cytotoxic effects on most tumor cells without major histocompatibility complex(MHC)*** increasing number of basic studies have focused on the development,antigen recognition,activation,and antitumor immune response ofγδT ***,γδT cell-based immunotherapeutic strategies are being developed,and the number of clinical trials investigating such strategies is *** review mainly summarizes the progress of basic research and the clinical application ofγδT cells in tumor immunotherapy to provide a theoretical basis for further the development ofγδT cell-based strategies in the future.

关键词： Gamma-delta T-cells T cell receptor CD1a Tumor immunotherapy Receptors,chimeric antigen Vδ1 cells αβT cells

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Spatial heterogeneity of soil water content in the reversion process of desertification in arid areas

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Journal of Arid Land 2011年第4期3卷 268-277页

作者： QuanLin MA Fang CHENG YouJun LIU FangLin Wang DeKuai ZHANG HuJia JIN Gansu Key Laboratory of Desertification Combating ＆ Minqin National studies Station for Desert Steppe ecosystem Gansu Desert Control Research Institute Lanzhou 730070 China Institute of Desertification studies Chinese Academy of Forestry Beijing 100091 China

Sandy soils in arid,rain-fed environments have low and limited water content,which is a principal factor limiting vegetation development,and a key constraint controlling the structure and functions of the ecological systems in arid *** spatial heterogeneity of soil water content is a major soil property,and a focus of soil science and *** the southern edge of the Tengger Desert,sample plots were selected from mobile sand dunes in desertified lands that had been enclosed for 5,15 and 25 years,*** study explored the dynamic and spatial heterogeneity of soil water content in these different layers of soil that were also in the reversion process of *** results showed that the soil water content of the mobile sand dunes was highest when in the initial stages of the reversion process of desertification,while the soil water content in the 0-20 cm,20-40 cm and 40-60 cm layers of soil was 1.769%,3.011%,and 2.967% respectively,presenting a restoring tendency after 25 years of *** were significant differences,as a whole,in the soil water content among different restoration stages and different soil layers,*** in soil water content,in different soil layers,at different restoration stages,exhibited exponential or spherical *** spatial distribution of soil water content exhibited a mosaic patch pattern with obvious spatial *** ratio of the heterogeneity of spatial autocorrelation to gross spatial heterogeneity was greater than 50%.The gross spatial heterogeneity of the 0-20 cm layer of soil improved gradually,while those of the 20-40 cm and 40-60 cm layers improved initially,then weakened in the reversion process of *** study revealed that restoration with sand-binding vegetation reduced soil water content,and increased its spatial heterogeneity in arid ***,after 25 years of vegetation-soil system restoration,the soil water content started to increase and it

关键词： Tengger Desert reversion process of desertification soil water content sand-binding vegetation geostatistical analysis

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Evaluation of periglacial landforms and formation of soil properties on the Mount Honaz,SW Türkiye

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Journal of mountain Science 2024年第9期21卷 3047-3067页

作者： SERİN Soner UNCU Levent DEDE Volkan TÜRKEŞMurat Institute of Social Sciences İstanbul Universityİstanbul 34119Türkiye Department of Geography BilecikŞeyh Edebali UniversityBilecik 11234Türkiye Department of Geography Ardahan UniversityArdahan 75002Türkiye Center for Climate Change and Policy studies Boğaziçi Universityİstanbul 34342Türkiye

The main aim of this study is to explain periglacial processes on the summits of Mount Honaz(2571 m a.s.l.),define periglacial landforms,and determine the relationships between morphometric features and topographic *** circles,stony earth circles,non sorted steps,and non sorted stripes were identified on the summits of Mount ***'s correlation coefficient(r)and linear regression analyses were performed by taking metric measurements from 125 periglacial landforms to describe their morphometric features(length,width,height)of periglacial landforms and explain the relationships between them and topographic factors(elevation,slope).To explain the relationships between periglacial landforms and soil properties,soil samples from 11 periglacial landforms were taken and *** landforms,which continue to develop on the summits of Mount Honaz today,have been evaluated with present climate *** of soil samples indicates a notable impact of parent material on the genesis of periglacial *** high ratio of organic matter in mud circle and non sorted step landforms and the high lime ratio in stony earth circle landforms prove a strong relationship between the formation mechanisms of landforms and the soil ***,it is consistent with the findings obtained from the analysis that severe periglacial processes and washing and scavenging events are experienced more on the northern slopes.

关键词： Periglacial processes and geomorphology Soil analysis Morphometric analysis Mount Honaz Türkiye

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Do introduced honeybees affect seed set and seed quality in a plant adapted for bird pollination?

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Journal of Plant Ecology 2017年第4期10卷 721-729页

作者： Amy-Marie Gilpin Justin C.Collette Andrew J.Denham Mark K.J.Ooi David J.Ayre centre for Sustainable ecosystem Solutions School of Biological SciencesUniversity of WollongongNorthfields AvenueWollongongNSW 2522Australia NSW Department of Premier and Cabinet Office of Environment and HeritagePO Box 1967HurstvilleNSW 2220Australia centre for ecosystem Science School of BiologicalEarth and Environmental SciencesUniversity of New South WalesSydneyNSW 2052Australia

Aims Worldwide,evidence suggests that exotic pollinators can disrupt plant mating ***,few studies have determined if pol-lination by the honeybee Apis mellifera(the world’s most widely introduced pollinator)reduces offspring quality when compared with pollination by native *** Australian Proteaceae provides an excellent opportunity to test the impact of honeybees in pol-lination systems that are adapted to birds and non-flying *** We compared the frequency of flower visitation and foraging behav-iour of birds and insects within seven populations of Banksia *** ericifolia is hermaphroditic and has large nectar-rich,orange inflorescences typical of bird and mammal pollinated *** a subset of the study populations,we compared the qual-ity of seed produced via an exclusion treatment(that only allowed invertebrates to access flowers)with an open-pollination treatment(potentially visited by mammals,birds and invertebrates),by meas-uring seed weight,germination rates(T50),percent germination,seedling height after 14 days since the emergence of the cotyledon and time to emergence of the *** Findings Apis mellifera was the only apparent insect pollinator and the most frequent flower visitor,while the open treatment inflorescences were also frequently visited by avian pollinators,primarily hone-yeater *** foraging behaviour of honeybees and honeyeat-ers showed striking differences that potentially affect patterns of pollen *** made significantly greater proportions of within *** plant movements and only 30%(n=48)of honeybees foraged for pollen(nectar foragers carried no pollen)whilst all birds were observed to contact both stigmas and anthers when foraging for *** these fundamental differences in behaviour,there was little effect of treatment on seed set or *** data show that while honeybees appear to alter patterns of pollen transfer within *** popu

关键词： Apis mellifera Banksia ericifolia Proteaceae seedling performance seed vigour

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mountain Commons: Changing Space and Status at Community Levels in the Himalayas

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Journal of mountain Science 2007年第2期4卷 124-135页

作者： Narpat S. JODHA International centre for Integrated mountain Development (ICIMOD) G.P.O. Box 3226 Kathmandu Nepal Sr. Research Associate (Policy Analyst)

This paper deals with the imperatives of nature-society interaction in the Himalayas as seen through CPR (Common Property Resources). It specifically looks at the process and factors that characterize the dynamics of the above interactions, with particular reference to the changing status and governance of CPRs at community levels. The paper puts together the synthesis of observations and inferences of different studies by ICIMOD and others in mountain regions, particularly in different parts of Nepal, India, Bhutan, Bangladesh, China and Pakistan. Rural CPRs (providing sustenance supplies and services) as an important component of a community’s natural resource base, manifest the institutional arrangements evolved by the communities to facilitate their adaptations to nature. The above process can be more clearly illustrated with reference to specific characteristics of mountain areas, called mountain specificities. However, over time, the situation of CPRs in terms of their extent and status, governance and management as well as contributions to community sustenance, has changed. The paper attempts toindicate potential lead lines for searching options for rehabilitation of CPRs, based on a closer under- standing of the factors contributing to their decline.

关键词： Nature-society interaction common property resources mountain regions Himalayas

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Mass Foliar Damage at Subalpine-Timberline Ecotone in Western Himalaya Due to Extreme Climatic Events

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American Journal of Climate Change 2012年第2期1卷 104-107页

作者： Ishwari Datt Rai Bhupendra Singh Adhikari Gopal Singh Rawat Department of Habitat Ecology Wildlife Institute of India Dehradun India ecosystem Services International Centre for Integrated Mountain Development Kathmandu Nepal

Glimpses of unusual climatic conditions such as high summer temperature, heavy rainfall as well as snowfall and low winter temperature were noticed during 2010-2011 in subalpine-timberline (2700 - 3600 m) zones of Western Himalaya. Abundant winter injury to the current year (2010) foliage and shoot of Rhododendron arboretum and Quercus semecarpifolia became apparent in winters of 2010-2011. The foliar and bud mortality both increased with elevation beyond 2800 m and maximum along the edges of forest. Rhododendron campanulatum was another species which also got affected throughout the Western Himalaya. Such events were not reported earlier from the region and current observations indicate the high sensitivity of the plant species to the extreme inter-annual climatic variations.

关键词： Foliar Damage Extreme Climate Western Himalaya

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An evaluation method for internal erosion potential of gravelly soil based on particle size distribution

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Journal of mountain Science 2022年第4期19卷 1203-1214页

作者： ZHU Qin SU Li-jun LIU Zhen-yu WANG Bin Key Laboratory of mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research centre on Earth Sciences Islamabad 45320Pakistan

Internal erosion occurs when fine particles escape from the soil driven by seepage flow,which is considered to be the crucial factor causing the failure of earth structures filled with gravelly *** objective of this paper is to suggest an appropriate method to assess internal erosion potential of gravelly *** analyzing the sensitivity of soil material to internal erosion,the variable(Dc15/df85)max and the content of coarse particles(Pc)are selected as the evaluation indexes(Dc15 and df85 are the diameters of 15%mass passing in the coarse component and 85%mass passing in the fine component,respectively).A series of gravelly soils with different particle size distributions are tested for internal erosion by the self-made *** on the test results,an evaluation method for the internal erosion of gravelly soil is *** soil is prone to internal erosion when 60%≤Pcstudies,which confirms the reliability of the *** proposed method makes it possible to accurately assess internal erosion of gravelly soil,and an alternative method is provided for engineers to determine whether there is a risk of internal erosion in earth structures consisting of gravelly soil.

关键词： Internal erosion Gravelly soil Evaluation method Particle size distribution Coarse particle content

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