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Analysis on the indicator species and ecological groups of pelagic ostracods in the East China Sea 被引量:9
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作者 XU Zhaoli 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第6期83-93,共11页
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 we... 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. 展开更多
关键词 ZOOPLANKTON pelagic ostracods ECOTYPE temperature SALINITY East China Sea indicator species
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A study on zooplankton distribution patterns and indicator species in Kuroshio upstream area and adjacent East China Sea 被引量:4
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作者 He Dehua, Wang Chunsheng, Liu Hongbin and Yang Guanming( Received July 9, 1990 accepted November 12, 1990) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第2期237-254,共18页
On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of... On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.The species composition of zooplankton in the study area is complex and varies, however, the tropic oceanic species predominates overwhelmingly. The distribution of different ecotype species evidences the distribution of different water masses and the state of mixture. The indicator species of each water mass are listed in the paper so as to provide grounds for the variation of currents in the Kuroshio area.The temperature and salinity of sea water are important factors affecting zooplankton distribution, composition and diversity , however the role of salinity is major. With the replacement of one season by another, the correlative levels of temperature and salinity to various zooplankton taxa are more or less significant. 展开更多
关键词 A study on zooplankton distribution patterns and indicator species in Kuroshio upstream area and adjacent East China Sea area
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Identifying Indicator Species in Habitats Created by Coastal Structures 被引量:1
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作者 Yi-Yu KUO Chun-Han SHIH +2 位作者 Ying-Chou LEE Wei-Tse CHANG Ta-Jen CHU 《China Ocean Engineering》 SCIE EI 2010年第1期117-134,共18页
In this paper, three approachs were developed to find indicator species from the habitat created by coastal structures. These approachs consist of a model of species co-occurrence probability, a model of k-environment... In this paper, three approachs were developed to find indicator species from the habitat created by coastal structures. These approachs consist of a model of species co-occurrence probability, a model of k-environmental factor probability and a composite model. Simultaneously, a case study was conducted in Hsinchu Fishing Port of north-western Taiwan. Based on the aforementioned models, three primary producer species, Ahnfeltiopsis flabelliformis, Chondrus ocellatus and Sarcodia montagneana, were chosen as the indicator species which had the highest co-occurrence probabilities and showed greater tolerance to more critical environment. It is imperative to understand how the three species under particular co-occurring conditions and environmental factors influence the composition of sessile assemblages in coastal water. The results indicate that for the purpose of increasing biodiversity, these models are feasible to find indicator species of artificial structures, and to help make it possible to design coastal structures based on biological considerations. This study provides an innovative approach for further advanced application in the artificial habitat of coast management. 展开更多
关键词 coastal structures indicator species sessile organisms ecological restoration
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Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt
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作者 Asmaa S ABO HATAB Yassin M AL-SODANY +2 位作者 Kamal H SHALTOUT Soliman A HAROUN Mohamed M EL-KHALAFY 《Journal of Arid Land》 SCIE CSCD 2024年第7期1000-1021,I0002-I0044,共65页
Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emira... Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic species in Egypt, i.e., Ⅰ Asphodelus refractus group, Ⅱ Agathophora alopecuroides var. papillosa group, Ⅲ Anvillea garcinii group, Ⅳ Reseda muricata group, V Agathophora alopecuroides var. alopecuroides group, Ⅵ Scrophularia deserti group, and Ⅶ Astragalus schimperi group. It's crucial to clearly define the Saharo-Arabian endemics and illustrate an updated verified database of these taxa for a given territory for providing future management plans that support the conservation and sustainable use of these valuable species under current thought-provoking devastating impacts of rapid anthropogenic and climate change in this region. 展开更多
关键词 ENDEMISM phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)
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The role of graveyards in species conservation and beta diversity:a vegetation appraisal of sacred habitats from Bannu,Pakistan 被引量:1
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作者 Saqib Kamran Shujaul Mulk Khan +5 位作者 Zeeshan Ahmad Amjad Ur Rahman Majid Iqbal Fazal Manan Zahoor Ul Haq Saif Ullah 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1147-1158,共12页
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... 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 approaches.It was hypothesized that variations in the age of graveyards would give rise to diverse plant communities under the impact of various edaphic and climatic factors.Quantitative ecological techniques were applied to determine various phytosociological attributes.All 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 analysis.CA 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)Melia-Rhazya-Peganum.Species 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 conservation.The 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 species.The 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 patterns.These results could further be utilized to evaluate the role of edaphic and climatic factors,indicator species and conservation management practices at a greater scale. 展开更多
关键词 Graveyards/Sacred groves Plant communities Multivariate statistical techniques indicator species Edaphic factors CONSERVATION PCORD software
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Species Diversity,Distribution,and Microhabitats of Anurans on Mt.Kalo-Kalo of the Mt.Kalatungan Range Natural Park,Bukidnon,Philippines 被引量:1
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作者 Von Carlo P.DELA TORRE Olga M.NUNEZA 《Asian Herpetological Research》 SCIE CSCD 2021年第1期58-75,共18页
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 ... 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 diseases.This study aimed to determine species diversity and local distribution of anurans in lower(1000–1400 masl)and upper(1400–1600 masl)montane forests on Mt.Kalo-Kalo of the Mt.Kalatungan Range Natural Park,Central Mindanao,Southern Philippines by employing standard sampling techniques for amphibians.We recorded a total of 251 individual anurans,representing 12 species during a brief recent study period.Mt.Kalo-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 endemics.Ansonia muelleri exhibited the highest local abundance and individuals of this species which constituted 73%of individual anurans observed.Most of the species encountered prefer terrestrial and aquatic microhabitats,specifically on the rocks and bank substrates along the rivers and streams.Three species of anurans(Philautus acutirostris,P.poecilius,and Rhacophorus bimaculatus)were strictly found in arboreal microhabitats.Limnonectes magnus and A.muelleri have overlapping microhabitats.Results indicate that for such a short survey and modest sampling effort,the lower and upper montane forests of Mt.Kalo-Kalo support high endemism of anuran species suggesting that conservation efforts continue to be a priority in this unique protected area. 展开更多
关键词 CONSERVATION ENDEMIC indicator species montane forest protected area
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Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forests in Nepal 被引量:1
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作者 Yagya P. ADHIKARI Anton FISCHER +3 位作者 Hagen S.FISCHER Maan B.ROKAYA Prakash BHATTARAI Axel GRUPPE 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1065-1075,共11页
Epiphytic plant species are an important part of biological diversity. It is therefore essential to understand the distribution pattern and the factors influencing such patterns. The present study is aimed at observin... Epiphytic plant species are an important part of biological diversity. It is therefore essential to understand the distribution pattern and the factors influencing such patterns. The present study is aimed at observing the patterns of species richness, abundances and species composition of epiphytic orchids and ferns in two subtropical forests in Nepal. We also studied the relationship of host plants(Schima wallichii and Quercus lanata) and epiphyte species. Data were collected in Naudhara community forest(CF) and the national forest(NF) in Shivapuri Nagarjun National Park. The data were analyzed using univariate and multivariate tests. In total, we recorded 41 species of epiphytes(33 orchid and 8 fern species). Orchid species abundance is significantlyhigher in CF compared to NF. Orchid species richness and abundance increased with increasing southern aspect whereas it decreased with increasing canopy cover, and fern species richness increased with host bark roughness. Orchid abundance was positively correlated with increasing bark p H, stem size, tree age and tree height and negatively correlated with increasing steepness of the area. Likewise, fern abundances were high in places with high canopy cover, trees that were tall and big, but decreased with increasing altitude and southern aspect. The composition of the orchid and fern species was affected by altitude, aspect, canopy cover, DBH, number of forks and forest management types. We showed that the diversity of orchid and fern epiphytes is influenced by host characteristics as well as host types. The most important pre-requisite for a high epiphyte biodiversity is the presence of oldrespectively tall trees, independent of the recent protection status. This means:(i) for protection, e.g.in the frame of the national park declaration, such areas should be used which host such old tall trees;and(ii) also in managed forests and even in intensively used landscapes epiphytes can be protected by letting a certain number of trees be and by giving them space to grow old and tall. 展开更多
关键词 Environmental factors Epiphytes Large trees indicator species Multivariate and univariate analyses Permutations tests
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Classifying forest inventory data into species-based forest community types at broad extents: exploring tradeoffs among supervised and unsupervised approaches
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作者 jennifer k.costanza don faber-langendoen +1 位作者 john w.coulston david n.wear 《Forest Ecosystems》 SCIE CSCD 2018年第1期91-107,共17页
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... 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 variables. Conclusions: The classifications have similarities and differences that reflect their differing approaches and Dbjectives. They are most consistent for forest community types that occur in a relatively narrow range of Invironmental conditions, and differ most for types with wide-ranging tree species. Environmental variables at variety of scales were important for predicting all classifications, though strongest for the empirical and FIA, guggesting that each is useful for studying how forest communities respond to of multi-scale environmental processes, including global change drivers. 展开更多
关键词 Big data Correspondence analysis Dominant species Forest communities Global change Hierarchical classification indicator species Random forests species assemblages
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Influence of edaphic factors on distribution and condition of Himalayan silver birch(Betula utilis D.Don)communities in the northwestern Indian Himalayas
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作者 Khashti DASILA Renu RAWAL +3 位作者 Tanay BARMAN Sher Singh SAMANT Anita PANDEY Veena PANDE 《Journal of Mountain Science》 SCIE CSCD 2024年第2期590-606,共17页
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 th... 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 planning.B.utilis is one of the most dominant tree species of treeline ecotone in the Himalayan Region.The species is also considered as indicator species for monitoring the past and recent climate change impact.The current study was carried out in the natural populations of B.utilis from the sub-alpine zone of North-western Indian Himalaya.The 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 family.Birch forests are found dominant in shady moist habitat and North West aspect.Geographical characteristics,anthropogenic and developmental activities affect the population structure of B.utilis and associated species.However,the species has fair regeneration status in the study area.The 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 vegetation.Biomass estimation of a representative population of B.utilis 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 B.utilis dominated forests. 展开更多
关键词 species composition indicator species Biomass North-western Indian Himalaya Regeneration Environmental variables
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Spatial and environmental effects on plant communities in the Yellow River Delta, Eastern China 被引量:8
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作者 宋创业 刘高焕 刘庆生 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期117-122,I0002,共7页
Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distributi... Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling methods. Results showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix chinensis. The vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble potassium. Among the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total variation. Spatial variation and spatial-structured environmental variation explain 11.8%, and 2.2%, respectively. Remained 40.8% of undetermined variation is attributed to biological and stochastic factors. 展开更多
关键词 detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis
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Spatial and environmental effects on plant communities in the Yellow River Delta,Eastern China 被引量:3
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作者 SONG Chuang-ye1, 2, LIU Gao-huan1, LIU Qing-sheng1 1 Institute of Geographic Sciences and Nature Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Graduated School of Chinese Academy of Sciences, Beijing 100039, China 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期117-122,共6页
Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspon-dence analyses(DCCAs) and a two-way indicator species analysis(TWINSPAN).The distribution pat... Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspon-dence analyses(DCCAs) and a two-way indicator species analysis(TWINSPAN).The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling methods.Results showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix chinensis.The vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble potassium.Among the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total variation.Spatial variation and spatial-structured environmental variation explain 11.8%, and 2.2%, respectively.Remained 40.8% of undetermined variation is attributed to biological and stochastic factors. 展开更多
关键词 detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis
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Preliminary Report on the Anurans of Mount Hilong-hilong, Agusan Del Norte, Eastern Mindanao, Philippines 被引量:3
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作者 Jeszianlenn L.PLAZA Marites B.SANGUILA 《Asian Herpetological Research》 SCIE CSCD 2015年第1期18-33,共16页
Mount Hilong-hilong is a key biodiversity area, spanning several municipalities in the provinces of the Caraga Region (Agusan del Norte, Agusan del Sur, Surigao del Norte and Surigao del Sur), northeastern Mindanao ... Mount Hilong-hilong is a key biodiversity area, spanning several municipalities in the provinces of the Caraga Region (Agusan del Norte, Agusan del Sur, Surigao del Norte and Surigao del Sur), northeastern Mindanao Island, southern Philippines. The Hilong-hilong massif remains one of the most signiifcant forested areas in Mindanao, threatened with habitat modification (forest removal, degradation) and other anthropogenic disturbances related to renewable resource extraction. Amphibians are key indicator species for environmental quality and are useful focal taxa for conservation efforts. Relying on historical museum database information and new survey work on Mount Hilong-hilong, we provide species accounts and describe microhabitat preferences of the anurans (frogs and toads) present in the area. Twenty-seven species representing seven anuran families were studied in detail at elevations between 700 to 1300 meters above sea level; 16 of these species are Mindanao faunal region endemics. Qualitative overlap in microhabitat use was observed, suggesting that, for the species recorded, intact forest may ensure species persistence to some levels of anthropogenic disturbance. A more extensive herpetofaunal survey is needed to fully estimate the herpetofaunal diversity of Mount Hilong-hilong. Because amphibians represent ifne-scale indicators of environmental quality and microendemism, we recommend appropriate ifne-scaled regional strategies geared towards the conservation of amphibians in the Caraga area, northeast Mindanao Island. 展开更多
关键词 environmental indicator species key biodiversity areas species accounts historical records microhabitat preferences anthropogenic disturbance
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Plant Communities and Factors Responsible for Vegetation Pattern in an Alpine Area of the Northwestern Himalaya 被引量:2
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作者 Man S.RANA S.S.SAMANT Y.S.RAWAT 《Journal of Mountain Science》 SCIE CSCD 2011年第6期817-826,共10页
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 distribution.We placed random plots cove... 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 distribution.We placed random plots covering different habitats and altitude to record species composition and environmental variables.Vegetation was classified using hierarchical cluster analysis and vegetation-environment relationships were evaluated with Canonical Correspondence Analysis.Four communities,each in alpine shrub and meadows were delineated and well justified in the ordination plots.Indicator species for the different communities were identified.Maximum species richness and diversity were found in community IV among shrub communities and community II among the meadows.Studied environmental variables explained 61.5% variation in shrub vegetation and 59.8% variation in meadows.Soil variables explained higher variability (~35%) than spatial variables (~21%) in both shrubs and meadows.Altitude,among the spatial variables and carbon/nitrogen ratio and nitrogen among the soil variables explained maximum variation.About 40% variations left unexplained.Latitude and species diversity among the other variables had significant correlation with ordination axes.Study showed that altitude and C/N ratio played a significant role in species composition.Extensive sampling efforts and inclusion of other non-studied variables are also suggested for better understanding. 展开更多
关键词 species diversity indicator species Environmental variable ORDINATION Explainedvariation
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Topography and soil content contribute to plant community composition and structure in subtropical evergreen-deciduous broadleaved mixed forests 被引量:5
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作者 Qichi Yang Hehe Zhang +4 位作者 Lihui Wang Feng Ling Zhengxiang Wang Tingting Li Jinliang Huang 《Plant Diversity》 CSCD 2021年第4期264-274,共11页
Topography and soil factors are known to play crucial roles in the species composition of plant communities in subtropical evergreen-deciduous broadleaved mixed forests.In this study,we used a systematic quantitative ... Topography and soil factors are known to play crucial roles in the species composition of plant communities in subtropical evergreen-deciduous broadleaved mixed forests.In this study,we used a systematic quantitative approach to classify plant community types in the subtropical forests of Hubei Province(central China),and then quantified the relative contribution of drivers responsible for variation in species composition and diversity.We classified the subtropical forests in the study area into 12 community types.Of these,species diversity indices of three communities were significantly higher than those of others.In each community type,species richness,abundance,basal area and importance values of evergreen and deciduous species were different.In most community types,deciduous species richness was higher than that of evergreen species.Linear regression analysis showed that the dominant factors that affect species composition in each community type are elevation,slope,aspect,soil nitrogen content,and soil phosphorus content.Furthermore,structural equation modeling analysis showed that the majority of variance in species composition of plant communities can be explained by elevation,aspect,soil water content,litterfall,total nitrogen,and total phosphorus.Thus,the major factors that affect evergreen and deciduous species distribution across the 12 community types in subtropical evergreendeciduous broadleaved mixed forests include elevation,slope and aspect,soil total nitrogen content,soil total phosphorus content,soil available nitrogen content and soil available phosphorus content. 展开更多
关键词 Environmental factors Plant community Two-way indicator species analysis Detrended correspondence analysis Evergreen-deciduous broadleaved mixed forests Northwestern of Hubei
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A preliminary study on the effects of line and selective thinning on bird communities in Hokkaido, northern Japan 被引量:1
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作者 Yuya Toyoshima Yuichi Yamaura +1 位作者 Yuki Yabuhara Futoshi Nakamura 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第3期553-559,共7页
In Japan, selective thinning is a common thinning method, though line thinning receives much attention because of its economic merits. In this study, we examined effects of the two thinning methods on bird communities... In Japan, selective thinning is a common thinning method, though line thinning receives much attention because of its economic merits. In this study, we examined effects of the two thinning methods on bird communities in Todo fir (Abies sachalinensis) plantations in Hok- kaido, Japan. We surveyed bird species in forests under four different management types - unthinned, selectively thinned, line-thinned planta- tion, and naturally regenerated forest (here after referred to as natural forest) stands - using a line-transect method. We also investigated vege- tation structure (canopy tree and understory) of these stands. Bird species richness did not differ between natural forests and plantations, while bird total abundance was greater in plantations than in natural forests. Bird species richness and total abundance were comparable among the three management types for plantations. Abundances of 10 bird species were different among the four management types, and five species were more abundant in line-thinned plantations. However, two species were more abundant in selectively thinned stands than in line-thinned stands, and they frequently appeared in natural forests. There were no distinct differ- ences in vegetation structure among the management types for planta- tions. Our results suggest that line thinning could be beneficial for some bird species in plantations. 展开更多
关键词 line thinning selective thinning Todo fir (Abies sachalinen-sis) plantation improved indicator species analysis bird community
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Winter distribution of diatom assemblages along the coastline of R.O.Korea in 2010 被引量:1
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作者 Joon Sang Park Kyun-Woo Lee +2 位作者 Seung Won Jung Taek-Kyun Lee Hyoung Min Joo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第6期68-77,共10页
Diatoms are a globally successful and eukaryotic photosynthetic organism with an ornamented silica external wall.The relationship between their valve morphology and habitat means that diatoms can be used as bioindicat... Diatoms are a globally successful and eukaryotic photosynthetic organism with an ornamented silica external wall.The relationship between their valve morphology and habitat means that diatoms can be used as bioindicators to characterize the aquatic environment.To estimate the differential distribution and diversity of diatom assemblages along the coastal line,we collected phytoplankton samples from 114 coastal sites of waters of R.O.Korea.We 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 Sea.Indicator 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 regions.This 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. 展开更多
关键词 diatom assemblage indicator species LIFE-FORM Korean coastal waters species diversity
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Plant functional type approach for a functional interpretation of altitudinal vegetation zones in the Alborz Mts., Iran 被引量:1
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作者 Halime MORADI Farideh ATTAR Jens OLDELAND 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2257-2269,共13页
Mountains are an excellent system for evaluating ecological and biogeographical patterns. The obvious variations of the environmental factors along the altitude create different zones with adapted plant assemblages. H... Mountains are an excellent system for evaluating ecological and biogeographical patterns. The obvious variations of the environmental factors along the altitude create different zones with adapted plant assemblages. However, few studies make use of plant functional type(PFT) for describing the variation of vegetation along altitudinal gradients. A PFT is a group of taxa with similar traits which respond similarly to the environmental gradients. In this study, we used PFTs as indicators describing five vegetation zones in the western Alborz Mt, Iran from 2000 – 4500 m. The plant trait data presented here covers six plant traits including growth form, stemleaf ratio, spinescence, hairiness, leaf consistency and plant height of 297 species. We considered altitude and soil factors to test the importance of environmental variables. We applied a multivariate analysis of three table ordination, i.e. environmental, species, and traits data to identify the PFTs. We further applied fourth-corner statistic to quantify trait-environment relationships. A constrained hierarchical clustering was used to detect five altitudinal zones and two zones of low and high nitrogen concentration. With regard to altitude wediscuss the distribution of species, traits and PFTs. Growth form, plant height and stem-leaf ratio were significantly related to altitude and nitrogen. We identified 19 PFTs from which 18 were significantly associated to one or more altitudinal zones. While the lower altitudinal zones contain a variety of PFTs higher altitudes contain less PFTs with the highest altitude containing only one single PFT, tiny rosette plants with soft mesomorphic leaves. We identified grazing and climatic harshness as well as rockiness as the most important drivers of the distribution of plant functional traits and types across the studied gradient. 展开更多
关键词 ELEVATION indicator species Analysis ORDINATION Leaf traits Trait-environment relationships
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Influence of soil and elevation on roadside cryptogam diversity in the tropical Andes
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作者 Paul Salinas Marina Mazon +4 位作者 Vinicio Carrion-Paladines Nixon Cumbicus Patricio Guzman Paolo Giordani Angel Benítez 《Forest Ecosystems》 SCIE CSCD 2022年第5期639-646,共8页
Background: The deforestation caused by road construction is one of the main drivers for both biodiversity and function loss in tropical ecosystems. Terricolous cryptogams are pioneers in colonizing roadside and they ... Background: The deforestation caused by road construction is one of the main drivers for both biodiversity and function loss in tropical ecosystems. Terricolous cryptogams are pioneers in colonizing roadside and they are limited by environmental and edaphic factors, thus, cryptogams may act as pioneers for ecosystem rehabilitation at roadside.Methods: This research was aimed at determining the diversity and composition of terricolous cryptogams, as well as their relationship with elevation and soil properties among roadside of the tropical Andes of Ecuador, in order to establish indicator species of this anthropized ecosystems. Five elevations were selected and in each one 50grids of 20 cm×30 cm were sampled(250 in total along the road), where occurrence, cover and identification of every cryptogam species were recorded. To evaluate the effect of elevation and soil properties on cryptogam richness, a linear model was conducted. Species composition among elevations was compared by non-metric multidimensional scaling(NMDS), and their relationship with the environmental variables through a correlation with adjusted axes was performed. A total of 72 species were recorded, those being 44 bryophytes and 28lichens. Species richness and composition of terricolous cryptogams were influenced by elevation and soil properties, thus the richness is higher at elevations E1, E2 and E3(2600, 2200 and 1800 m a.s.l.), differing from low elevations E4 and E5(1400 and 1000 m a.s.l.). Higher elevations with specific soil conditions(e.g bulk density, nitrogen and silt) harbored different cryptogam communities than those in lower elevations.Conclusions: A combination of both elevation and soil properties are shaping the colonization by terricolous cryptogams commnunities. As such, 18 species were identified as the best indicators for all sets of environmental conditions at the roadside, which can therefore be considered for monitoring ecological processes in tropical areas. Use of biocrusts for restoration is an emerging field. If implemented in the study region, elevation and soil drivers may help to better chose the more suitable cryptogam species to manage and stabilize roadside in tropical roads. 展开更多
关键词 BRYOPHYTES indicator species Beta diversity LICHENS Richness Ecuador
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Elevational distribution of butterflies in the Himalayas: a case study from Langtang National Park, Nepal
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作者 Ranjit PANDEY Kapil K KHADKA +2 位作者 Anuj GHIMIRE Puja JHA Umesh PATHAK 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1384-1390,共7页
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 resp... 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 here.Interestingly, 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. 展开更多
关键词 Butterflies indicator species Nepal Range shift Climate change HIMALAYAS
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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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作者 Ran Ye Chunying Ge +6 位作者 Qiong Wang Qing Xu Guofeng Xu Yongkang Yan Mingli Qin Yanhong Cai Yuejun Fei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第6期100-110,共11页
Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic systems.This study provided insights into the relationships ... Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic systems.This 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 Sea.Results demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in summer.As for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,respectively.They exhibited strong indications in response to environmental changes.These 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. 展开更多
关键词 ecological thresholds phytoplankton community environmental gradients indicator species coastal waters of northern Zhejiang Province
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