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Analysis on the indicator species and ecological groups of pelagic ostracods in the East China Sea

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Acta Oceanologica Sinica 2008年第6期27卷 83-93页

作者： XU Zhaoli Key and Open laboratory of Marine and Estuary Fisheries of Ministry of Agriculture East China Sea Fisheries Research Insti-tute Chinese Academy of Fisheries Sciences Shanghai 200090 China

Ecological adaptation and ecological groups of pelagic ostracods were examined in the East China Sea （23°30′-33°00′N, 118°30′ -128°00′E）, in relation to temperature and salinity. The data were collected in four surveys conducted from 1997 to 2000. The density, yield density, or negative exponent models were used to determine the optimal temperature and salinity of water for the thriving growth of pelagic ostracods. Thereafter, ecological groups and potential distribution patterns of pelagic ostracods were determined based on the predicted parameters such as optimal temperature and salinity, consulting the geographic distribution. The analytical results indicate that, among the numerical dominant pelagic ostracods in the East China Sea （ECS）, Euconchoecia aculeata, E. elongata, E. chierchiae, E. maimai, and Cypridina dentata, etc. are offshore subtropical water species. These species are widely distributed in the area, and they can be brought by the warm current to north offshore during spring and winter. The predicated optimal temperature （OT） and optimal salinity （OS） for Paraconchoecia decipiens, P. echinata, P. spini- fera, P. oblonga, Conchoecia magna and Porroeciaporrecta are all greater than 25℃ and 34 separately. These species are mainly distributed in the waters of the Kuroshio, the Taiwan Warm Current, and the Taiwan Strait, and therefore are designated as ocean- ic tropical water species. On the other hand, Pseudoconchoecia concerttrica is considered as offshore subtropical water species based on its geographical distribution although its OT is 19℃. The other species, though their OSs are approximately 34 and with OTs ranging from 20° to 25℃, are considered as offshore subtropical water species because they were found to be widely distributed from the South China Sea to the East China Sea.

关键词： zooplankton pelagic ostracods ecotype temperature salinity East China Sea indicator species

Ecological thresholds of phytoplankton community across environmental gradients in the harmful algal blooms-frequently-occurring,subtropical coastal waters,East China Sea

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Acta Oceanologica Sinica 2021年第6期40卷 100-110页

作者： Ran Ye Chunying Ge Qiong Wang Qing Xu Guofeng Xu Yongkang Yan Mingli Qin Yanhong Cai Yuejun Fei Marine Environmental Monitoring Centre of Ningbo Ningbo 315012China

Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic *** study provided insights into the relationships concerning ecological thresholds of phytoplankton communities and individual taxon in response to environmental changes in coastal waters of northern Zhejiang Province,East China *** demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in *** for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,*** exhibited strong indications in response to environmental *** findings highlighted that phytoplankton community structure in this region was stable when environmental gradients were below the thresholds of sensitive species,whereas potential harmful algal blooms may occur when environmental gradients exceeded the thresholds of tolerant species.

关键词： ecological thresholds phytoplankton community environmental gradients indicator species coastal waters of northern Zhejiang Province

Winter distribution of diatom assemblages along the coastline of *** in 2010

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Acta Oceanologica Sinica 2022年第6期41卷 68-77页

作者： Joon Sang Park Kyun-Woo Lee Seung Won Jung Taek-Kyun Lee Hyoung Min Joo Library of Marine Samples Korea Institute of Ocean Science&TechnologyGeoje 53201R.O.Korea Marine Biotechnology Research Center Korea Institute of Ocean Science&TechnologyBusan 49111R.O.Korea Risk Assessment Research Center Korea Institute of Ocean Science&TechnologyGeoje 53201R.O.Korea Unit of Next Generation IBRV Building Program Korea Polar Research InstituteIncheon 21990R.O.Korea

Diatoms are a globally successful and eukaryotic photosynthetic organism with an ornamented silica external *** relationship between their valve morphology and habitat means that diatoms can be used as bioindicators to characterize the aquatic *** estimate the differential distribution and diversity of diatom assemblages along the coastal line,we collected phytoplankton samples from 114 coastal sites of waters of *** applied the unweighted pair-group technique using the arithmetic averages clustering method to cluster the sampling sites,apart from those where the biota consisted of other groups,such as dinoflagellates,into four regions:the Yellow Sea,South Sea,southern East Sea,and northern East *** species analysis in each region led to the selection of tychoplanktonic,chain-forming,attached species to substrates and psychrophilic indicator diatoms,respectively,each of which represented a planktonic lifestyle associated with one of the four *** study shows the diatom assemblages to serve as bioindicators of Korean coastal water in winter,and the subsequent seasonal survey will provide a starting point for the improved understanding of Korean diatom-based ecoregions,in both time and space.

关键词： diatom assemblage indicator species life-form Korean coastal waters species diversity

The role of graveyards in species conservation and beta diversity:a vegetation appraisal of sacred habitats from Bannu,Pakistan

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Journal of Forestry Research 2020年第4期31卷 1147-1158页

作者： Saqib Kamran Shujaul Mulk Khan Zeeshan Ahmad Amjad Ur Rahman Majid Iqbal Fazal Manan Zahoor Ul Haq Saif Ullah Department of Plant Sciences Quaid-i-Azam UniversityIslamabadPakistan

Graveyards or sacred groves are often places of natural vegetation protected by spiritual believers because of their sacred beliefs and indigenous culture.A study of graveyards was conducted to determine their role in species conservation,community formation,and associated indicators and species composition using multivariate statistical *** was hypothesized that variations in the age of graveyards would give rise to diverse plant communities under the impact of various edaphic and climatic *** ecological techniques were applied to determine various phytosociological *** the data were put in MS Excel for analysis in PCORD and CANOCO softwares for cluster analysis(CA),two-way cluster analysis(TWCA),indicator species analysis and canonical correspondence *** and TWCA through Sorenson distance measurements identified five major graveyard plant communities:(1)FicusBougainvillea-Chenopodium;(2)Acacia-Datura-Convolvulus;(3)Ziziphus-Vitex-Abutilon;(4)Acacia-Lantana-Salsola;and(5)*** such as Capparis decidua,Herniaria hirsuta,Salvadora oliedes and Populus euphratica were only present inside graveyards rather than outside and advocate the role of graveyards in species *** impact of different environmental and climatic variables plus the age of the graveyards were also assessed for comparison of plant communities and their respective indicator *** results indicate that higher chlorine concentration,age of graveyards,low soil electrical conductivity,lower anthropogenic activities,higher nitrogen,calcium and magnesium concentrations in the soil,and sandy soils were the strong environmental variables playing a significant role in the formation of graveyard plant communities,their associated indicators and species distribution *** results could further be utilized to evaluate the role of edaphic and climatic factors,indicator species and conservation management practices at a gr

关键词： Graveyards/Sacred groves Plant communities Multivariate statistical techniques indicator species Edaphic factors Conservation PCORD software

Influence of edaphic factors on distribution and condition of Himalayan silver birch(Betula utilis ***)communities in the northwestern Indian Himalayas

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Journal of Mountain Science 2024年第2期21卷 590-606页

作者： Khashti DASILA Renu RAWAL Tanay BARMAN Sher Singh SAMANT Anita PANDEY Veena PANDE G.B.Pant National Institute of Himalayan Environment Almora 263643India Centre of Excellence on Sustainable Land Management Indian Council of Forestry Research and EducationDehradun 248006India Uttarakhand State Council for Science&Technology Dehradun 248015India Department of Biotechnology Graphic Era(Deemed to be University)Dehradun 248002India Department of Biotechnology Kumaun UniversityNainital 263136India

The basic concept of phytosociology is crucial for the assessment of species composition and dynamic ecological succession of forests supporting ecological services,functions,disturbance,and resilience that lead to the development of integrated areas such as ecological niche modeling and contribute to identifying the valuable bio-indicators which can be used in framing conservation and management *** is one of the most dominant tree species of treeline ecotone in the Himalayan *** species is also considered as indicator species for monitoring the past and recent climate change *** current study was carried out in the natural populations of *** from the sub-alpine zone of North-western Indian *** birch dominated forest harbors a total of 305 plant species comprising Angiosperms(51 families,160 genera and 277 species),Gymnosperms(03 families,05 genera and 07 species)and Pteridophytes(07 families,11 genera and 21 species)with Asteraceae,Ranunculaceae and Rosaceae as dominant *** forests are found dominant in shady moist habitat and North West *** characteristics,anthropogenic and developmental activities affect the population structure of *** and associated ***,the species has fair regeneration status in the study *** acidic nature of soil pH and spatial variation in edaphic characteristics may be due to geographical differences,rooting patterns and litter accumulation of below and above-ground *** estimation of a representative population of *** from each site showed that TAGBD,TCD and TBD were found maximum in ST3(Hamta Pass II site).The CCA analysis determined that environmental variables such as altitude,organic matter,available phosphorous,organic carbon,available nitrogen,and electrical conductivity played a significant role in determining tree species composition and distribution in *** dominated forests.

关键词： species composition indicator species Biomass North-western Indian Himalaya Regeneration Environmental variables

species Diversity,Distribution,and Microhabitats of Anurans on ***-Kalo of the *** Range Natural Park,Bukidnon,Philippines

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Asian Herpetological Research 2021年第1期12卷 58-75页

作者： Von Carlo P.DELA TORRE Olga M.NUNEZA Department of Biological Sciences and Environmental Studies University of the Philippines MindanaoMintal.Tugbok District.Davao City 8022Philippines Wildlife-Human Interaction Studies Ecological Researchand Biodiversity Conservation Laboraory.University of the PhilippinesMindanaoMintalTugbok DistrictDavao City 8022Philippines Department of Biological Sciences and Biodiversity Laboratory Premier Research lnstitute of Science and MathematicsMindanaoState University-lligan Institute of TechnologyA.Bonifacio Avelligan City 9200Philippines

Anurans are considered good indicators of habitat quality due to their bi-phasic life mode,limited dispersal abilities,and sensitivity to environmental changes brought about by habitat fragmentation,pollution,climate change,and emerging infectious *** study aimed to determine species diversity and local distribution of anurans in lower(1000–1400 masl)and upper(1400–1600 masl)montane forests on ***-Kalo of the *** Range Natural Park,Central Mindanao,Southern Philippines by employing standard sampling techniques for *** recorded a total of 251 individual anurans,representing 12 species during a brief recent study ***-Kalo’s upper montane forest has a higher diversity index(H’=1.276)than the lower montane forest(H’=0.851).Despite the very low diversity indices,the level of endemism of anurans was 100%where ten of the recorded species are Mindanao Faunal Region endemics and an additional two species are Philippine *** muelleri exhibited the highest local abundance and individuals of this species which constituted 73%of individual anurans *** of the species encountered prefer terrestrial and aquatic microhabitats,specifically on the rocks and bank substrates along the rivers and *** species of anurans(Philautus acutirostris,***,and Rhacophorus bimaculatus)were strictly found in arboreal *** magnus and *** have overlapping *** indicate that for such a short survey and modest sampling effort,the lower and upper montane forests of ***-Kalo support high endemism of anuran species suggesting that conservation efforts continue to be a priority in this unique protected area.

关键词： conservation endemic indicator species montane forest protected area

Classifying forest inventory data into species-based forest community types at broad extents： exploring tradeoffs among supervised and unsupervised approaches

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Forest Ecosystems 2018年第1期5卷 91-107页

作者： jennifer k.costanza don faber-langendoen john w.coulston david n.wear Department of Forestry and Environmental Resources North C arolina State University3041 Cornwalis RdResearch Triangle ParkRaleighNC 27709USA NatureServe 4600 N.Fairfax Dr7th FloorArlingtonVA 22203USA Southern Research Station USDA Forest ServiceBlacksburgVAUSA Southern Research Station USDA Forest ServiceRaleighNCUSA

Background： Knowledge of the different kinds of tree communities that currently exist can provide a baseline for assessing the ecological attributes of forests and monitoring future changes. Forest inventory data can facilitate the development of this baseline knowledge across broad extents, but they first must be classified into forest community types. Here, we compared three alternative classifications across the United States using data from over 117,000 U.S. Department of Agriculture Forest Service Forest Inventory and Analysis （FIA） plots. Methods： Each plot had three forest community type labels：（1）＂FIA＂ types were assigned by the FIA program using a supervised method; （2）＂USNVC＂ types were assigned via a key based on the U.S. National Vegetation Classification; （3）＂empirical＂ types resulted from unsupervised clustering of tree species information. We assessed the degree to which analog classes occurred among classifications, compared indicator species values, and used random forest models to determine how well the classifications could be predicted using environmental variables. Results： The classifications generated groups of classes that had broadly similar distributions, but often there was no one-to-one analog across the classifications. The Iongleaf pine forest community type stood out as the exception： it was the only class with strong analogs across all classifications. Analogs were most lacking for forest community types with species that occurred across a range of geographic and environmental conditions, such as Ioblolly pine types, indicator species metrics were generally high for the USNVC, suggesting that LJSNVC classes are floristically well-defined. The empirical classification was best predicted by environmental variables. The most important predictors differed slightly but were broadly similar across all classifications, and included slope, amount of forest in the surrounding landscape, average minimum temperature, and other climate variab

关键词： Big data Correspondence analysis Dominant species Forest communities Global change,Hierarchical classification indicator species Random forests species assemblages

Elevational distribution of butterflies in the Himalayas: a case study from Langtang National Park, Nepal

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Journal of Mountain Science 2017年第7期14卷 1384-1390页

作者： Ranjit PANDEY Kapil K KHADKA Anuj GHIMIRE Puja JHA Umesh PATHAK Oklahoma State University Department of Integrative Biology University of Arkansas Department of Biological Sciences Tribhuvan University Central Department of Zoology Oklahoma State University Tribhuvan University Central Department of Environmental Sciences

Mountain ecosystems are relatively more vulnerable to climate change since human induced climate change is projected to be higher at high altitudes and latitudes. Climate change induced effects related to glacial response and water hazards have been documented in the Himalayas in recent years, yet studies regarding species' response to climate change are largely lacking from the mountains and Himalayas of Nepal. Changes in distribution and latitudinal/altitudinal range shift, which are primary adaptive responses to climate change in many species,are largely unknown due to unavailability of adequate data from the past. In this study, we explored the elevational distribution of butterflies in Langtang Village Development Committee(VDC) of Langtang National park; a park located in the high altitudes of Nepal. We found a decreasing species richness pattern along the elevational gradient considered ***, elevation did not appear to have a significant effect on the altitudinal distribution ofbutterflies at family level. Also, distribution of butterflies in the area was independent of habitat type,at family level. Besides, we employed indicator group analysis(at family level) and noticed that butterfly families Papilionidae, Riodinidae, and Nymphalidae are significantly associated to high, medium and low elevational zone making them indicator butterfly family for those elevational zones, respectively. We expect that this study could serve as a baseline information for future studies regarding climate change effects and range shifts and provide avenues for further exploration of butterflies in the high altitudes of Nepal.

关键词： Butterflies indicator species Nepal Range shift Climate change Himalayas

Plant Communities and Factors Responsible for Vegetation Pattern in an Alpine Area of the Northwestern Himalaya

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Journal of Mountain Science 2011年第6期8卷 817-826页

作者： Man S.RANA S.S.SAMANT Y.S.RAWAT Department of Plant Science Government Degree College G.B.Pant Institute of Himalayan Environment & Development Department of Botany D.S.B.CampusKumaun University

The study intended to describe the alpine vegetation of a protected area of the northwestern Himalaya and identify the important environmental variables responsible for species *** placed random plots covering different habitats and altitude to record species composition and environmental *** was classified using hierarchical cluster analysis and vegetation-environment relationships were evaluated with Canonical Correspondence *** communities,each in alpine shrub and meadows were delineated and well justified in the ordination *** species for the different communities were *** species richness and diversity were found in community IV among shrub communities and community II among the *** environmental variables explained 61.5% variation in shrub vegetation and 59.8% variation in *** variables explained higher variability (～35%) than spatial variables (～21%) in both shrubs and ***,among the spatial variables and carbon/nitrogen ratio and nitrogen among the soil variables explained maximum *** 40% variations left *** and species diversity among the other variables had significant correlation with ordination *** showed that altitude and C/N ratio played a significant role in species *** sampling efforts and inclusion of other non-studied variables are also suggested for better understanding.

关键词： species diversity indicator species Environmental variable Ordination Explainedvariation