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Land use induced blurring of forest-grassland transition in north-west Himalaya-A case study using Moving Split Window boundary detection technique

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Journal of Mountain Science 2020年第12期17卷 3085-3096页

作者： Shevita PANDITA Harish Chander DUTT ecological Engineering Laboratory Department of BotanyUniversity of JammuJammu-180006India

Transition zone or ecotone is a unique community sandwiched between two communities/ecosystems/*** ecotones in Himalaya remained unexplored for many ecological aspects like biodiversity,phyto-sociology,boundary detection and even impact of change in land use pattern(anthropogenic activity).The most accepted and widespread technique called as Moving Split Window(MSW) technique is used for detection of vegetation and environmental boundaries at four different sites in the lesser stratum of north-west *** the four sites were at different distances from the nearest human inhabited *** activities like grazing,herb collection,wood collection *** common at proximal *** activities have led to the change in land use *** this study,we have tried to work out the impact of the change in land use pattern(human interference) on the vegetation and basic environmental parameters like soil pH,electrical conductivity and moisture on forestgrassland ecotone in north-west *** on mountain steepness was also collected and *** dissimilarity profile using the statistical tool Squared Euclidian Distance(SED) indicated that species turnover locations increase with the increase in distance of ecotones from human *** ecotones at distant locations from human villages are characterized with blunt as well as sharp peaks for vegetation data,however,conditions are reverse in case of the proximal *** study also reveals that as the distance between the ecotone and human settlements increases,the complex conditions like multiple vegetation boundaries prevails on the *** this regard,land use induced blurring of forest-grassland transition in north-west Himalaya is summed up in the study.

关键词： Ecotone Moving Split Window Squared Euclidean Distance Transect Dissimilarity function Environment variables

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Emergence of spatiotemporal chaos arising from far-field breakup of spiral waves in the plankton ecological systems

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Chinese Physics B 2009年第2期18卷 506-515页

作者：刘权兴孙桂全靳祯李百炼 department of Mathematics North University of China ecological Complexity and Modeling Laboratory Department of Botany and Plant Sciences University of California

It has been reported that the minimal spatially extended phytoplankton-zooplankton system exhibits both temporal regular/chaotic behaviour, and spatiotemporal chaos in a patchy environment. As a further investigation by means of computer simulations and theoretical analysis, in this paper we observe that the spiral waves may exist and the spatiotemporal chaos emerge when the parameters are within the mixed Turing-Hopf bifurcation region, which arises from the far-field breakup of the spiral waves over a large range of diffusion coefficients of phytoplankton and zooplankton. Moreover, the spatiotemporal chaos arising from the far-field breakup of spiral waves does not gradually invade the whole space of that region. Our results are confirmed by nonlinear bifurcation of wave trains, We also discuss ecological implications of these spatially structured patterns.

关键词： reaction diffusion systems travelling wave bifurcation

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An arrow in the quiver: evaluating the performance of Hyptis suaveolens(L.) Poit. in different light levels

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ecological Processes 2024年第2期13卷 130-147页

作者： Kanhaiya Shah Gyan Prakash Sharma R.Sagar department of Environmental studies University of Delhi department of botany Banaras Hindu University

Background Hyptis suaveolens（L.） Poit.,native to the American tropics,is a pantropical annual plant and a major invasive species throughout *** was anticipated that the availability of sunlight,coupled with its superior reproductive potential,persistent propagule bank,and dispersal ability,could lead to an increase in the growth and spread of this invader,thus potentially impeding herbaceous growth and diversity in non-native *** its ecological fitness and competitive performance will be useful to manage the spread of *** in natural ecosystems that are facing a wide range of anthropogenic *** The present study is a three-tier *** the first tier,a field study was conducted to assess the patterns of *** abundance and herbaceous species diversity in response to light availability(sun,842-1072μmol m-2s-1and shade 253-341 μmol m-2S-1) in the tropical dry deciduous ecosystems in the Vindhyan highlands,***,the impact of *** abundance on the resident native and non-native species abundance and diversity was also *** the second tier,a randomized common garden experiment was conducted to understand the trait fitness of *** in sun(940 μmol m-2s-1) and shade(300 μmol m-2s-1) *** the third tier,a plant growth chamber experiment with high-light(940 μmol m-2s-1) and low-light(300 μmol m-2s-1)treatments was done to learn how *** partitions its biomass between aboveground and belowground plant *** The field study indicated that the sunlit areas had a higher abundance of *** and a lower diversity of resident herbaceous species than the shaded *** common garden experiment showed that sun-dwelling *** individuals performed better in germinative,vegetative,eco-physiological,and reproductive traits than the shade-dwelling *** growth chamber experiment exhibited that plants grown in high-light environment had greater seed germi

关键词： Invasive species Native species Species diversity Life-history trait Oskar syndrome Plasticity index

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Genetic variation in relation to adaptability of three mangrove species from the Indian Sundarbans assessed with RAPD and ISSR markers

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Journal of Forestry Research 2018年第2期29卷 300-309页

作者： Nirjhar Dasgupta Paramita Nandy Chandan Sengupta Sauren Das Agricultural and ecological Research Unit Indian Statistical Institute Deaprtment of botany Sister Nibedita Government General Degree College for Girls' department of botany University of Kalyani

Rich genetic polymorphism is important for plants to adapt to changes because it enables the plant to make anatomical,physiological and biochemical changes in response to abiotic *** characteristics,demographic interference and a cumulative decrease in freshwater influx in the Indian Sundarbans region have proved detrimental to some economically important *** this study,genetic polymorphism of three mangrove species,Xylocarpus granatum,Excoecaria agallocha,and Phoenix paludosa,was assessed using RAPD and ISSR molecular ***,already in distress in the Sundarbans,had the least genetic polymorphism,14.56%in the RAPD analysis and 12.92% in the *** higher genetic polymorphism was recorded for the profusely growing *** and ***: 24.66 and26.4% in RAPD; 24.87 and 20.32% in ISSR analysis respectively.A UPGMA dendrogram constructed using the similarity matrix from RAPD,ISSR and combined datashowed that for ***,the least and highest salinity zones clustered together,whereas for *** and ***,higher and lower salinity areas clustered in different ***’s genetic diversity,calculated from RAPD and ISSR data,was also in accordance with 0.0637 and 0.0583 for ***,respectively,much lower than0.0794 and 0.0818 for *** and 0.0799 and 0.0688 for *** opposing degree of polymorphism might be attributed to the profusely growing *** and *** and precarious status of *** throughout the Indian Sundarbans.

关键词： Polymorphism ISSR Mangrove RAPD Sundarbans

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Plant-to-plant direct competition for belowground resource in an overlapping depletion zone

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Journal of Arid Land 2009年第1期1卷 9-15页

作者： Amit CHAKRABORTY ecological Complexity and Modeling Laboratory Department of Botany and Plant SciencesUniversity of California Center for Conservation Biology University of California

In response to limited availability of soil resources in basal root zone, plant extends its roots into nearby resource-rich zones to fulfill essential resource demands for survival and reproduction. This root proliferation into that enriched zones occupied by other plants constitutes interplant overlapping rooting zones and thereby the overlapping depletion zones, causing reduction in resource uptake by neighboring plants. By incorporating this mechanism into the classic resource competition model, we study interplant direct competition through their rooting system in an overlapping depletion zone. The model results indicate an extension of Tilman’s R* rule that has already been proved true when plants compete indirectly through their effect on shared resources. The results reveal that plant’s direct competitive ability (i.e., the ability to occupy an overlapping depletion zone by excluding others) can be characterized by its R*-value, where a best competitor having lowest R*-value excludes others from an overlapping zone and occupies the zone by depleting the resource level to the lowest as in its non-overlapping depletion zone. By analyzing the model, we find a suite of traits that confers R* variation among directly competing plants. This suite of traits would be a useful proxy measure for R* that do not necessarily require to establish equilibrium field monoculture—a requirement for R* measurement in the field.

关键词： resource capture efficiency niche differentiation root proliferation resource depletion zone

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Endangered lowland oak forest steppe remnants keep unique bird species richness in Central Hungary

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Journal of Forestry Research 2022年第1期33卷 343-355页

作者： GáborÓnodi Zoltán Botta‑Dukát Dániel Winkler Tamás Rédei Institute of Ecology and botany Centre for Ecological ResearchVácrátótHungary department of botany and Biodiversity Research University of ViennaViennaAustria Institute of Wildlife Management and Wildlife Biology University of SopronSopronHungary

The biodiversity of natural or semi-natural native,old oak woodlands have high conservation importance,especially in landscapes of monocultural forest plantations and arable *** a wider variety of microhabitats and foraging sources,such old oak forests can provide essential habitat for native forest bird *** conducted a study using bird point counts to compare the forest bird communities of old pedunculate oak(Quercus robur)remnants with native and non-native plantations in central Hungary in a landscape of mostly arable fields,settlements,and monocultural *** surveys were carried out in old oak forest remnants,middle-aged oak,white poplar(Populus alba),hybrid poplar(Populus×euramericana),black locust(Robinia pseudoacacia),and pine(Pinus spp.)*** has been carried out in nine study sites,where all six habitat types were represented(with a few exceptions),to determine total abundance,species richness,Shannon–Wiener diversity,species evenness,dominant and indicator species,and guild *** found that old oak forest remnants were the most diverse habitats among the studied forest types,while hybrid poplar and pine plantations exhibited the lowest avian *** avian guilds most sensitive to the loss of old oak forest remnants were ground foragers,bark foragers,cavity-nesters,residents,and Mediterranean migratory *** habitats were more diverse than non-native *** results suggest that it is important to conserve all remaining high biodiversity old oak stands and to avoid clear-cutting of monocultural plantations in favour of practices such as mixed-species plantations,longer rotation lengths,or retention forestry.

关键词： Forest bird community Bird conservation Old oak forest-steppe remnant Plantation forestry Forest conservation Non-native plantation

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Is intraspecific trait differentiation in Parthenium hysterophorus a consequence of hereditary factors and/or phenotypic plasticity?

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Plant Diversity 2023年第5期45卷 611-620页

作者： Amarpreet Kaur Shalinder Kaur Harminder Pal Singh Daizy R.Batish department of botany Panjab UniversityChandigarh 160014India department of Environment studies Panjab UniversityChandigarh 160014India

Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most ***,we studied the persistence of substantial morpho-functional variations within the individuals of alien invasive plant,Parthenium hysterophorus in Chandigarh,India,through field *** on observed differences,the individuals were categorized into two morphotypes,PAand *** higher leaf area,leaf biomass,and chlorophyll content as compared with ***,PBhad a higher stem circumference,stem specific density,twig dry matter content,profuse branching,bigger canopy,and better reproductive output than *** substantiate the persistence of intraspecific variations in P. hysterophorus and to deduce the possible genesis of these variations,we propagated both the morphotypes under experimental conditions in winter and *** from the key morpho-functional differences observed during the field studies,protein and carbohydrate metabolism were studied in leaves and roots of the propagated *** in plant metabolism were observed only during the early growth period,whereas the morpho-functional traits varied in the mature flowering *** effect of growth season was highly significant on all the studied morpho-functional and biochemical parameters(p ≤0.05).Parent morphotypes(P) and interactions between morphotypes and seasons significantly affected several growth parameters(p ≤0.05).The analyses revealed that the contrasting growth conditions at the time of transplantation and early growth may regulate the phenotype of P. *** pattern of intraspecific variations observed during the study is justified to consider morphotype PAas winter biotype and morphotype PBas summer biotype of P. *** study points towards the role of plasticity or a combination of genetic and environmental(G×E) factors in producing the p

关键词： Biochemical traits Carbohydrate metabolism Morpho-functional traits Phenotypic variations Protein metabolism Ragweed parthenium

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Assessment of pollution levels and human health risk of heavy metals in dust deposited on Yerevan＇s tree leaves (Armenia)

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Acta Geochimica 2017年第1期36卷 16-26页

作者： N. Maghakyan G. Tepanosyan O. Belyaeva L. Sahakyan A. Saghatelyan department of Environmental Geochemistry Center for Ecological-Noosphere Studies of the National Academy of Sciences Abovian-68 0025 Yerevan Republic of Armenia

The total concentrations of Cd,As,Pb,Cr,Ni,Co,Zn,Cu,Ag,Hg,and Mo were determined in the atmospheric dust of the city of Yerevan by atomic absorption spectrometry(AAnalyst PE 800).Heavy metal pollution levels were evaluated by calculating geo-accumulation(I_(geo)) and summary pollution(Z_c) *** human health risk was assessed using the United States Environmental Protection agency's human health risk assessment *** results show that mean contents of all elements tested except Ni and Cr were substantially higher than local geochemical background *** to the I_(geo),Yerevan territory is strongly-to-extremely polluted by As,Ag,Hg,Mo,and *** Z_c assessment indicated that very high pollution was detected in 36%of samples,high in 32%,average in 12%,and low in 20%.The health risk assessment revealed a noncarcinogenic risk(HI >1) for children at 13 samplings sites and for adults at one sampling *** children the risk was due to elevated levels of Mo,Cd,Co,and As,while for adults,only *** risk(>1:1,000,000) of As and Cr via ingestion pathway was observed in 25 and 14 samples,*** study,therefore,is the base for further detailed investigations to organize problematic site remediation and risk reduction measures.

关键词： Urban dust Heavy metals Pollution levels Health risk assessment

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Non-timber forest products and their contribution to healthcare and livelihood security among the Karbi tribe in Northeast India

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ecological Processes 2019年第1期8卷 492-512页

作者： Puranjoy Mipun Nazir Ahmad Bhat Dipankar Borah Yogendra Kumar Centre for Advanced studies in botany North-Eastern Hill UniversityShillongMeghalaya 793022India department of botany Rajiv Gandhi UniversityDoimukhArunachal Pradesh 791112India

Introduction:Non-timber forest products(NTFPs)have been an essential source for food,medicine,and handicraft products among the indigenous populations living in forested areas for *** research on the restoration of the importance of NTFPs and their value addition could potentially guide the development of new nutraceutical products in the *** present study aims to investigate the diversity of non-timber forest products of the Karbi Anglong District of Assam in Northeast ***:Multistage sampling technique was used for the study.A total of 70 respondents from 7 randomly selected villages were interviewed with a well-developed semi-structured questionnaire to explore the utilisation of *** analysis was done using four quantitative indices:(a)use report(UR),(b)use value(UV),(c)informant consensus factor(ICF),and(d)fidelity level(FL).Results:A total of 138 plant species belonging to 59 families distributed in 110 genera were recorded and identified as NTFPs of 1 type or the *** include 42%having ethnomedicinal use,33%as edible forest products,15%as household building materials and utensils,6%as spices and condiments,and 4%as herbal *** the medicinal plant species,Abroma augustum(L.)L.f.,Amaranthus spinosus L,and Geophila repens(L.)*** the highest ICF and ***:The present study confirms that NTFPs have played an essential role in the healthcare and livelihood of the indigenous people of the Karbi tribe throughout their generations and continue to do ***,the species with high value for both ICF and FL could be used for the development of new,cheap,effective,and eco-friendly herbal formulations for healthcare management leading to economic and social benefits to the indigenous ***,anthropogenic pressure and overexploitation of NTFPs may lead to the loss of this precious natural resource from this area.

关键词： East Karbi Anglong Ethnobotany Forest income NTFPs Wildlife sanctuary Quantitative study Medicinal plants

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Benefitting from Geoinformatics: Estimating Floristic Diversity of Warwan Valley in Northwestern Himalaya,India

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Journal of Mountain Science 2015年第4期12卷 854-863页

作者： Akhtar Hussain MALIK Irfan RASHID Aijaz Hassan GANIE Anzar Ahmad KHUROO Ghulam Hassan DAR Centre for Biodiversity and Taxonomy Department of Botany University of Kashmir department of Earth Sciences University of Kashmir department of botany University of Kashmir Mahatma Gandhi Chair on Ecology and Environment Centre for Biodiversity Studies Baba Ghulam Shah Badshah University

The Himalaya harbor rich floristic diversity which is of immense scientific interest and socio-economic *** this study, floristic diversity of a remote alpine valley has been studied based on information extracted from remotely sensed satellite data along with field surveys undertaken during *** of vegetation information from satellite data revealed that ~75% of the area is covered with natural vegetation which comprises lush green coniferous forests, alpine pastures and alpine scrub *** inputs from vegetation information extracted from satellite data, comprehensive field surveys were planned to document the floristic diversity of the *** of species composition showed a total of 285 plant species,belonging to 191 genera in 60 *** these, 250 species are herbs, 14 shrubs, 2 sub-shrubs and 19 *** dicotyledons are represented by 240 species, monocotyledons 30, gymnosperms 04, andpteriodophytes 11 *** is the largest family with 35 *** the present study, 5species（Corydalis cashmeriana, Hippophae rhamnoides, Primula minutissima, Saussurea sacra and Inula orientalis） have been recorded for the first time from this Himalayan *** study demonstrates the benefits of geo-informatics in floristic studies, particularly the robustness of remotely sensed data in identifying areas with potentially high species richness, which would be otherwise difficult in a complex mountainous terrain using traditional floristic surveys *** present study is expected to provide baseline scientific data for cutting edge studies relating to long term ecological research, bioprospecting, possible impacts of changing climate on vegetation and sustainable use of plant resources in this Himalayan region.

关键词： Floristic diversity Northwestern Himalaya Remote sensing GIS Vegetation sampling

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