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Monitoring the impact of climate change and human activities on grassland vegetation dynamics in the northeastern Qinghai-Tibet Plateau of China during 2000–2015

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Journal of Arid Land 2019年第5期11卷 637-651页

作者： XIONG Qinli XIAO Yang Marwa Waseem A HALMY Mohammed A DAKHIL LIANG Pinghan LIU Chenggang ZHANG Lin bikram pandey PAN Kaiwen Sameh B EL KAFRAWAY CHEN Jun CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China College of Biology and Environmental Sciences Jishou UniversityJishou 416000China Department of Environmental Science Faculty of ScienceAlexandria UniversityAlexandria 21511Egypt University of Chinese Academy of Sciences Beijing 100039China Botany and Microbiology Department Faculty of ScienceHelwan UniversityCairo 11790Egypt School of Government Sun Yat-sen UniversityGuangzhou 510275China CAS Key Laboratory of Tropical Plant Resources and Sustainable Use Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglun 666303China National Authority for Remote Sensing and Space Sciences Cairo 11790Egypt

Climate change and human activities can influence vegetation net primary productivity(NPP), a key component of natural ecosystems. The Qinghai-Tibet Plateau of China, in spite of its significant natural and cultural values, is one of the most susceptible regions to climate change and human disturbances in the world. To assess the impact of climate change and human activities on vegetation dynamics in the grassland ecosystems of the northeastern Qinghai-Tibet Plateau, we applied a time-series trend analysis to normalized difference vegetation index(NDVI) datasets from 2000 to 2015 and compared these spatiotemporal variations with trends in climatic variables over the same time period. The constrained ordination approach(redundancy analysis) was used to determine which climatic variables or human-related factors mostly influenced the variation of NDVI. Furthermore, in order to determine whether current conservation measures and programs are effective in ecological protection and reconstruction, we divided the northeastern Qinghai-Tibet Plateau into two parts: the Three-River Headwater conservation area(TRH zone) in the south and the non-conservation area(NTRH zone) in the north. The results indicated an overall(73.32%) increasing trend of vegetation NPP in grasslands throughout the study area. During the period 2000–2015, NDVI in the TRH and NTRH zones increased at the rates of 0.0015/a and 0.0020/a, respectively. Specifically, precipitation accounted for 9.2% of the total variation in NDVI, while temperature accounted for 13.4%. In addition, variation in vegetation NPP of grasslands responded not only to long-and short-term changes in climate, as conceptualized in non-equilibrium theory, but also to the impact of human activities and their associated perturbations. The redundancy analysis successfully separated the relative contributions of climate change and human activities, of which village population and agricultural gross domestic product were the two most impor

关键词： climate change human activities NDVI variation Qinghai-Tibet Plateau redundancy analysis vegetation net primary productivity

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Diversity of Flowering Plants in Nubri Valley, Manaslu Conservation Area, Central Nepal

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American Journal of Plant Sciences 2017年第6期8卷 1484-1498页

作者： Shova Sapkota bikram pandey Krishna Kumar Shrestha Central Department of Botany Tribhuvan University Kirtipur Kathmandu Nepal

Central Nepal has long history in the field of botanical investigation in contrast with different parts of the nation. Nevertheless, the present study area (Manaslu Conservation Area) is still under-explored. The present floristic study was carried out with the aim of fulfilling this gap by giving particular attention on flowering plants and their documentation. Two field visits were directed in May-June 2012 and September-October 2012 in two unique seasons with a specific end goal to gather plant samples of both seasons. On the contrary, herbarium specimens were prepared and later identified at Tribhuvan University Central Herbarium (TUCH) and National Herbarium and Plant Laboratory (KATH). The present study uncovers the presence of 276 species of flowering plants belonging to 78 families and 200 genera of which 63 families belong to dicotyledons and 15 families belong to monocotyledons. Among these, 17 species (6.15%) of climbers, 178 species (64.49%) of herbs, 58 species (21.01%) of shrubs and 23 species (8.33%) of trees are found. Economically important flowering plants comprise about 156 species where 75 species are used as medicine, 29 species as fuel wood, 23 species as fodder, 29 species are edible, 6 species are for religious purpose, 5 specifically for construction purpose, 10 for ornamental and 13 species reported to have miscellaneous uses. MCA accounts to 9 flowering plant species for research and development and agro-technology development and 12 species are listed under IUCN and CAMP threatened categories. MCA and its affinity are likewise house to 10 endemic flowering plants. As from the study it can be inferred that Manaslu Conservation Area (MCA) is a treasure hub of flowering plants that not only represent its economic importance rather it is also a house to threaten and endemic flowering plants. Thus, proper management plans must be implemented for the conservation of resources in MCA.

关键词： Flowering Plants Documentation Economic Important Plants Threatened Endemic Manaslu Conservation Area

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Ecology and Conservation Status of Threatened Orchid <i>Dactylorhiza hatagirea</i>(D. Don) Soo in Manaslu Conservation Area, Central Nepal

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American Journal of Plant Sciences 2014年第23期5卷 3483-3491页

作者： Prakash Bhattarai bikram pandey Raj Kumar Gautam Rita Chhetri Central Department of Botany Tribhuvan University Kathmandu Nepal Makawanpur Multiple Campus Hetauda Nepal National Herbarium and Plant Laboratories Lalitpur Nepal

Dactylorhiza hatagirea (D. Don) Soo, commonly known as “Panchaunle”, is an important medicinal plant species distributed throughout the Himalaya region. The present work was conducted in order to assess its availability in natural habitats because of its medicinal properties, cultural significance and declining population density. The work focused primarily on its ecological features and conservation status. The density of D. hatagirea was found to be 2.18 individuals·m-2 with frequency and abundance being 81.81% and 2.67 individuals·m-2, respectively. We considered grazing, trampling, number of cattle and distance to settlement as anthropogenic factors. While grazing and trampling were shown to have a significant, negative impact on population density, we observed no significant change in the number of the species with respect to number of cattle and distance to settlement. We conclude that the species is threatened and that anthropogenic factors have a significant effect on its habitation in the study area.

关键词： Anthropogenic Grazing Medicinal Plants Population Density Threatened

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Current climate overrides past climate change in explaining multi-site beta diversity of Lauraceae species in China

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Forest Ecosystems 2022年第2期9卷 186-199页

作者： Ziyan Liao Youhua Chen Kaiwen Pan Mohammed A.Dakhil Kexin Lin Xianglin Tian Fengying Zhang Xiaogang Wu bikram pandey Bin Wang Niklaus E.Zimmermann Lin Zhang Michael P.Nobis CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu610041China University of Chinese Academy of Sciences Beijing100039China Swiss Federal Institute for Forest Snow and Landscape Research WSLZürcherstrasse 111CH-8903BirmensdorfSwitzerland Botany and Microbiology Department Faculty of ScienceHelwan UniversityCairo11790Egypt Department of Forest Sciences University of HelsinkiP.O.Box 27HelsinkiFI-00014Finland Academy of Agriculture and Forestry Qinghai UniversityXining810016China

Background:We aimed to characterise the geographical distribution of Sørensen-based multi-site dissimilarity(β_(sor))and its underlying true turnover(β_(sim))and nestedness(βsne)components for Chinese Lauraceae and to analyse their relationships to current climate and past climate ***:We used ensembles of small models(ESMs)to map the current distributions of 353 Lauraceae species in China and calculated β_(sor) and its β_(sim) and β_(sne) *** tested the relationship between β_(sor),β_(sne) and β_(sim) with current climate and past climate change related predictors using a series of simultaneous autoregressive(SAR_(err))***:Spatial distribution of β_(sor)of Lauraceae is positively correlated with latitude,showing an inverse rela-tionship to the latitudinalα-diversity(species richness)*** β_(sor) occurs at the boundaries of the warm temperate and subtropical zones and at the Qinghai-Tibet Plateau due to high β_(sne).The optimized SAR_(err) model explainsβ_(sor) andβ_(sne) well,but notβ_(sim).Current mean annual temperature determinesβ_(sor) and β_(sne) of Lauraceae more than anomalies and velocities of temperature or precipitation since the Last Glacial ***:Current low temperatures and high climatic heterogeneity are the main factors explaining the high multi-siteβ-diversity of *** contrast to analyses of the β-diversity of entire species assemblages,studies of single plant families can provide complementary insights into the drivers of β-diversity of evolutionarily more narrowly defined entities.

关键词： Biodiversity conservation Current climate Ensemble modelling Multi-siteβ-diversity Nestedness Past climate change True turnover

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Peoples’ Perception and Conservation of Dactylorhiza hatagirea (D. Don) Soóin Manaslu Conservation Area, Central Nepal

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American Journal of Plant Sciences 2016年第12期7卷 1662-1672页

作者： bikram pandey Arbindra Timilsina Binita pandey Chhabi Lal Thapa Kamal Bahadur Nepali Pradeep Neupane Resham Thapa Sunil Kumar Gaire Mohan Siwakoti Central Department of Botany Tribhuvan University Kirtipur Nepal Key Laboratory of Agricultural Water Resources Center for Agricultural Resources Research Institute of Genetic and Developmental Biology The Chinese Academy of Sciences Shijiazhuang China University of Chinese Academy of Sciences Beijing China Central Department of Zoology Tribhuvan University Kirtipur Nepal National Botanical Garden Godawari Lalitpur Nepal

The present study analyzes the information and perception of the local community of Samagaun VDC, Manaslu Conservation Area Project (MCAP) regarding Dactylorhiza hatagirea (D. Don) Soó (Orchidaceae). We assessed the local peoples’ perception on its population status, its availability, factors causing its decline and management practices of this terrestrial orchids. A pre-designed questionnaire was used to gather information targeting the age group between 25 and 60 years (n = 75, 45 male and 30 female). Most of the informants (76%) believe that the abundance of this orchid is declining. Over grazing of domestic animals, over harvesting and lack of awareness among the local community were determined to be the major causes of decline of D. hatagirea in the study area. Protection measures as prescribed by the informants were control grazing, raising awareness among the individuals and sustainable harvestings for the long-term conservation of the species. Systematic management plans that incorporate the participation of local individuals and prioritization of their views will be applicable for the proper conservation of the species.

关键词： Local Perceptions Conservation and Management Orchid Dactylorhiza hatagirea Samagaun VDC Manaslu Conservation Area

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Effect of Environment on Photo-detachment Dynamics of Halide Ions： A Model Approach

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Chinese Journal of Chemical Physics 2010年第1期23卷 30-38,I0001页

作者： bikram Nath Chandan Kumar Mondal 萨哈核物理研究所晶体学和分了生物学司加尔各答700064 贾德普大学物理化学部化学系加尔各答700032

A two dimensional model approach for the photodetachment dynamics of closed shell an-ionic systems in presence of external light field have been proposed in the context of polar environmental media. The effects of strong coupling between the solvent polarization and the extra charge in the system were studied by a simple model. The electronic states of con-cerned halide ions are represented by a two dimensional model Hamiltonian with a potential V（x,y）=-V0e^-σ（x^2＋y^2）. The time dependent Fourier grid Hamiltonian method have been used to follow the detachment process with fairly high intensities of light. The environmental effects on the dynamics are sought to be modeled by two different ways. The first one was the presence of polar solvents which perturb the energy levels of anionic systems by changing the effective potential surface and the second one was allowing the fluctuation of the well depth randomly to mimic the system in a more realistic view point. The average detachment rate constant is calculated as a function of important parameters of the used light field to explain the effects of solvent field on the dynamical behavior of dipole bound anionic system at least in a qualitative way.

关键词： Photodetachment dynamics Environmental effect Time-dependent Fourier grid Hamiltonian Stochastic deactivation

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Mapping Sensitive Vegetation Communities in Mining Eco-space using UAV-LiDAR

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International Journal of Coal Science & Technology 2022年第3期9卷 185-200页

作者： bikram Pratap Banerjee Simit Raval Agriculture Victoria Grains Innovation Park110 Natimuk Road3400 HorshamVICAustralia School of Minerals and Energy Resources Engineering University of New South Wales2052 SydneyNSWAustralia

Near earth sensing from uncrewed aerial vehicles or UAVs has emerged as a potential approach for fne-scale environmental *** systems provide a cost-efective and repeatable means to acquire remotely sensed images in unprecedented spatial detail and a high signal-to-noise *** is increasingly possible to obtain both physiochemical and structural insights into the environment using state-of-art light detection and ranging(LiDAR)sensors integrated onto *** sensitive environments,such as swamp vegetation in longwall mining areas,is essential yet challenging due to their inherent *** practices for monitoring these remote and challenging environments are primarily *** is partly due to an absent framework and challenges of using UAV-based sensor systems in monitoring such sensitive *** research addresses the related challenges in developing a LiDAR system,including a workfow for mapping and potentially monitoring highly heterogeneous and complex *** involves amalgamating several design components,including hardware integration,calibration of sensors,mission planning,and developing a processing chain to generate usable *** also includes the creation of new methodologies and processing routines to establish a pipeline for efcient data retrieval and generation of usable *** designed systems and methods were applied to a peat swamp environment to obtain an accurate geo-spatialised LiDAR point *** of the LiDAR data was tested against ground-based measurements on various aspects,including visual assessment for generation LiDAR metrices maps,canopy height model,and fne-scale mapping.

关键词： Upland swamps Mine surveying Monitoring Environment sustainability Drones and laser scanning

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A robust approach to identify roof bolts in 3D point cloud data captured from a mobile laser scanner

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International Journal of Mining Science and Technology 2021年第2期31卷 303-312页

作者： Sarvesh Kumar Singh Simit Raval bikram Banerjee School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW 2052Australia Agriculture Victoria HorshamVIC 3400Australia

Roof bolts such as rock bolts and cable bolts provide structural support in underground *** assessment of these support structures is critical to maintain roof stability and minimise safety risks in underground *** study proposes a robust workflow to classify roof bolts in 3 D point cloud data and to generate maps of roof bolt density and *** workflow was evaluated for identifying roof bolts in an underground coal mine with suboptimal lighting and global navigation satellite system(GNSS)signals not *** approach is based on supervised classification using the multi-scale Canupo classifier coupled with a random sample consensus(RANSAC)shape detection algorithm to provide robust roof bolt *** issue of sparseness in point cloud data has been addressed through upsampling by using a moving least squares *** accuracy of roof bolt identification was measured by correct identification of roof bolts(true positives),unidentified roof bolts(false negatives),and falsely identified roof bolts(false positives)using correctness,completeness,and quality *** proposed workflow achieved correct identification of 89.27%of the roof bolts present in the test ***,considering the false positives and false negatives,the overall quality metric was reduced to 78.54%.

关键词： Mobile laser scanning Roof bolts Support system planning Roof monitoring Change detection Underground roadways

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A review of laser scanning for geological and geotechnical applications in underground mining

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International Journal of Mining Science and Technology 2023年第2期33卷 133-154页

作者： Sarvesh Kumar Singh bikram Pratap Banerjee Simit Raval School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW 2052Australia Agriculture Victoria Grains Innovation ParkHorshamVIC 3400Australia

Laser scanning can provide timely assessments of mine sites despite adverse challenges in the operational *** there are several published articles on laser scanning,there is a need to review them in the context of underground mining *** this end,a holistic review of laser scanning is presented including progress in 3D scanning systems,data capture/processing techniques and primary applications in underground *** scanning technology has advanced significantly in terms of mobility and mapping,but there are constraints in coherent and consistent data collection at certain mines due to feature deficiency,dynamics,and environmental influences such as dust and *** suggest that laser scanning has matured over the years for change detection,clearance measurements and structure mapping ***,there is scope for improvements in lithology identification,surface parameter measurements,logistic tracking and autonomous *** scanning has the potential to provide real-time solutions but the lack of infrastructure in underground mines for data transfer,geodetic networking and processing capacity remain limiting ***,laser scanners are becoming an integral part of mine automation thanks to their affordability,accuracy and mobility,which should support their widespread usage in years to come.

关键词： Mine automation Point cloud Rock mass characterisation Change detection Data registration Georeferencing

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Antioxidant activity and identification of bioactive compounds from leaves of Anthocephalus cadamba by ultra-performance liquid chromatography/electrospray ionization quadrupole time of flight mass spectrometry

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Asian Pacific Journal of Tropical Medicine 2012年第12期5卷 977-985页

作者： Madhu Chandel Upendra Sharma Neeraj Kumar bikram Singh Satwinderjeet Kaur Department of Botanical and Environmental Sciences Guru Nanak Dev UniversityAmritsar-143005 India Natural Plant Products Division CSIR-Institute of Himalyan Bioresource Technology(Council of scientific and Industrial research)PalampurH.P.-176061 India

Objective:To evaluate the antioxidant potential of different extract/fractions of Anthocephalus cadamba（***）（Roxb.） Miq.（Rubiaceae） and study the tentative identification of their active ***:The extract/fractions were screened for antioxidant activity using various in vitro assays *** assay,ABTS assay,superoxide anion radical scavenging assay, reducing power assay and plasmid DNA nicking *** phenolic content of extract/fractions was determined by colorimetric *** ultra-performance LC-electrospray-quadrupoletime of flight mass spectrometry method was used to analyse the active constituents of extract/ fractions of ***:The ethyl acetate fraction was found to be most active fraction in all the assays as compared to other extract/*** IC50 value of ethyl acetate fraction （ETAC fraction） was 21.24μg/mL,1.12μg/mL,9.68μg/mL and S7.81μg/mL in DPPH assay, ABTS assay,reducing power assay and superoxide scavenging assay *** the extract/ fractions also showed the potential to protect the plasmid DNA（pBR322） against the attack of hydroxyl radicals generated by Fenton’s *** bioactive compounds were identified by UPLC-ESI-QTOF-MS,by comparing the mass andλmax with literature ***:The potential of the extract/fractions to scavenge different free radicals in different systems indicated that they may be useful therapeutic agents for treating radical-related pathologic damage.

关键词： Anthocephalus cadamba Antioxidant activity UPLC-ESI-QTOF-MS

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