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Assessment of the Characteristics of Demersal Fish Communities Using Species-and Trait-Based Approaches in the Coastal Habitats Along Rongcheng Bay,Shandong Peninsula,China
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作者 YUAN Shunjie SUN Xin +3 位作者 TU Zhong SUN Jie WANG Xianning ZHANG Peidong 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期786-796,共11页
Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities al... Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities along a coastal habitat in Rongcheng Bay,Shandong Peninsula,China with both species-based and biological trait-based approaches.The field survey was carried out monthly using traps from April to October of 2018,and divided into three seasons(spring:April and May;summer:June,July and August;autumn:September,October and November).The study area included five distinct habitats:seagrass bed,natural rocky reef,bare sand,artificial reef together with natural rocky reef,and artificial reef together with bare sand.We analyzed the fish communities with three taxonomic diversity indices,including Shannon-Wiener,Simpson,and Pielou Evenness,as well as four functional diversity indices,including FRic,FEve,FDiv,and FDis,based on 7 functional groups which are categorized into 27 traits.The results showed that there were no significant differences in taxonomic diversity indices among different habitats in the three seasons.However,significant differences were found in the functional richness of fish communities among different habitats in three seasons.Seagrass bed represented the highest functional richness in spring and autumn.This study demonstrates that seagrass bed is very important in enhancing the functional diversity of fish communities in a complex habitat.The study also indicates that the combination of taxonomic diversity and functional diversity will provide a more detailed description of the characteristics of fish communities. 展开更多
关键词 complex habitat biological traits BIODIVERSITY fish communities
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Designated critical habitats for U.S.imperiled species are not protected from climate and land-use change
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作者 Aimee Delach Laura A.Nunes +1 位作者 Alex Borowicz Theodore C.Weber 《Geography and Sustainability》 CSCD 2024年第3期482-490,共9页
Designation of critical habitat is an important conservation tool for species listed as threatened or endangered under the United States(U.S.)Endangered Species Act(ESA).While this is an important protective mechanism... Designation of critical habitat is an important conservation tool for species listed as threatened or endangered under the United States(U.S.)Endangered Species Act(ESA).While this is an important protective mechanism,lands designated as critical habitat could still be subject to degradation and fragmentation if they are not also in a protected status that prioritizes biodiversity conservation.Additionally,most designations of critical habitat do not explicitly take climate change into account.The objective of our study was to determine whether and to what extent critical habitats for species listed under the ESA are located within protected areas and areas previously identified as climate refugia or climate corridors,to inform management strategies to better conserve and recover these species.We mapped the designated critical habitats of 153 ESA-listed species and measured their overlap with previously-identified areas of climate refugia and corridors(CRC),and also with lands designated as nature-protected by U.S.Geological Survey’s Gap Analysis Project(GAP Status 1 or 2)and working lands with wildlife habitat potential(GAP Status 3).Only 18%of all designated critical habitat is located on lands that are both in CRC and nature-protected,and only 9%of species had over half of their designated critical habitats in such lands.84%of species had<25%overlap of their critical habitats with these areas.Critical habitats may therefore not fulfill their essential role of helping imperiled species persist and recover. 展开更多
关键词 Endangered Species Act Critical habitat Climate refugia Climate corridors Protected areas Biodiversity conservation
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Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China
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作者 YANG Ao TU Wenqin +9 位作者 YIN Benfeng ZHANG Shujun ZHANG Xinyu ZHANG Qing HUANG Yunjie HAN Zhili YANG Ziyue ZHOU Xiaobing ZHUANG Weiwei ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2024年第10期1380-1408,共29页
In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of... In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China. 展开更多
关键词 HALOPHYTES climate change global warming maximum entropy(MaxEnt)model soil salinization suitable habitats Northwest China
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Influence of Climatic Changes and Anthropogenic Activities on the Distribution and Habitats of Senegalia senegal in Niger: A Forecast and Ecological Analysis
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作者 Abdoul Kader Soumaila Sina Idrissa Soumana +1 位作者 Amadou Garba Ali Mahamane 《Journal of Geoscience and Environment Protection》 2024年第11期29-40,共12页
The primary objective of this study is to assess the impact of climate change on the current and future spatial distribution of areas suitable for the growth of Senegalia senegal, a forest species of significant agro-... The primary objective of this study is to assess the impact of climate change on the current and future spatial distribution of areas suitable for the growth of Senegalia senegal, a forest species of significant agro-ecological and socio-economic importance. To achieve this objective, the MaxEnt (Maximum Entropy) model was utilized, incorporating species presence points alongside bioclimatic variables. To project future distributions, three climatic models-CCCMA, HadCM3, and CSIRO were employed under the A2 scenario to predict the species’ distribution by the year 2050. Currently, habitats highly favorable for the conservation of the species are situated in the Sahelo-Sudanian and Sudanian zones, accounting for 6.81% of the national territory. All models forecast a substantial increase in habitats highly favorable for the future conservation of S. senegal, with a total expected growth of 448.9%. Conversely, moderately favorable and unfavorable habitats are predicted to decrease by 106.26% and 78.59%, respectively. These findings provide crucial data for the long-term conservation strategy of this species, which holds significant ecological and agronomic potential for the Sahelian region. 展开更多
关键词 Modeling Maximum Entropy Suitable habitat Senegalia senegal Distribution NIGER
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Propagation Dynamics of Forced Pulsating Waves for a Time Periodic Lotka-Volterra Cooperative System with Nonlocal Effects in Shifting Habitats
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作者 Zewen Gong 《Journal of Applied Mathematics and Physics》 2024年第10期3402-3421,共20页
In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternativ... In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternatively-coupling upper-lower solution method, we establish the existence of forced pulsating waves, as long as the shifting speed falls in a finite interval where the endpoints are obtained from KPP-Fisher speeds. The asymptotic behaviors of the forced pulsating waves are derived. Finally, with proper initial, the stability of the forced pulsating waves is studied by the squeezing technique based on the comparison principle. 展开更多
关键词 Nonlocal Effects Time Periodic Lotka-Volterra System Forced Pulsating Waves Shifting habitats
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Modeling foraging habitats of Hume’s Pheasant (Syrmaticus humiae) in Dazhong Mountain, Yunnan, southwestern China 被引量:5
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作者 周伟 李宁 +3 位作者 邓忠坚 张庆 李明会 王学荣 《Chinese Birds》 2010年第4期236-243,共8页
We modeled foraging habitats of Hume’s Pheasant (Syrmaticus humiae) on a macro-habitat level using ArcGIS in an attempt to provide scientific reference for management and restoration of habitats. Field work was condu... We modeled foraging habitats of Hume’s Pheasant (Syrmaticus humiae) on a macro-habitat level using ArcGIS in an attempt to provide scientific reference for management and restoration of habitats. Field work was conducted from March to April in 2006 and 2008, and from October to November in 2005 and 2008 in Dazhong Mountain, Yunnan Province, southwestern China. The selection of ecological factors was estimated by means of a resource selection index, distance analysis and the method of hierarchical habitat selection. The foraging habitat patches were modeled spatially by ArcGIS. The results show that actual and potential foraging patches overlapped considerably in spring and autumn. The number and total areas of patches in the autumn were smaller than those in the spring. The minimum and average areas of patches in the autumn were larger than those in the spring, while the maximum areas of actual and potential foraging patches in the autumn were equal to those in the spring. Similarity in the selection for survival and safety consideration in both seasons was the main strategy for landscape factors of habitats by Hume’s Pheasant, while seasonal difference in selecting a landscape matrix was their secondary strategy, affecting landscape factors in the habitat. Changes of foraging patches in both seasons reflect a difference of resources requirement by the bird. Fragmentation and miniaturization of foraging patches would result in the formation of a meta-population of Hume’s Pheasant. 展开更多
关键词 Hume’s Pheasant (Syrmaticus humiae) foraging strategy habitat modeling habitat patch
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Determination of Poliumoside and Forsythoside B in Different Parts of Callicarpa kwangtungensis and Its Plants from Different Habitats 被引量:1
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作者 李开斌 孙刚 +2 位作者 马四补 晏晨 李春植 《Agricultural Science & Technology》 CAS 2016年第5期1080-1082,1088,共4页
[Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components(poliumoside and forsythoside B... [Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components(poliumoside and forsythoside B) in the plant and to compare the contents of these components in the medicinal materials from different habitats.[Methods] Comparison and analysis of the contents of the two target components in different parts(root,branch,leaf and fruit) of Callicarpa kwangtungensis from the same habitat and in Callicarpa kwangtungensis from different production areas were performed according to the pharmacopoeia standard.[Result]The highest content of poliumoside wasdetected in fruit,and the content of forsythoside B was the highest in the branch.The contents of the two kinds of components were in order of branch fruit leafroot;The contents of the components were four times higher than China pharmacopeia(0.5%) in Jian,Tonggu,Anyuan,and Ganzhou of Jiangxi Province and the fifth area,Taijiang County of Qiandongnan Miao and Dong Autonomous Prefecture(QMDAP),among which Ganzhou and Taijiang showed the highest contents.[Conclusion] The differences of poliumoside and forsythoside B were obvious in different habitats and different parts of Callicarpa kwangtungensis. 展开更多
关键词 Callicarpa kwangtungensis CONTENTS Different habitats Different parts
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Protection and Construction Measures of Wild Animals' Habitats in Ecological Green Land Design in Town-and-City Concentration Areas of China
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作者 凌静 吴迪 +2 位作者 辜彬 王思麒 罗言云 《Journal of Landscape Research》 2012年第5期61-64,共4页
Town-and-city concentration area is confronted with ecological degeneration due to the expansion of urbanization,and enriching urban bio-diversity is conducive to the improvement of ecological function of urban green ... Town-and-city concentration area is confronted with ecological degeneration due to the expansion of urbanization,and enriching urban bio-diversity is conducive to the improvement of ecological function of urban green system.The paper has studied how to increase urban bio-diversity by making use of urban green lands for protection and construction of wild animals' habitats,and proposed the significance and theoretical idea for protection and construction of wild animals' habitats.By taking ecological green lands design in Qinglongchang of Chengdu City for example,it has analyzed the current situation of animals' diversity;proposed to plan corridor,construct biological channel and provide multiporous habitats;listed plants' selection and collocation mode;and finally illustrated how to set artificial facilities for attraction of animals.It hopes to provide a reference for the design of ecological green lands in cities advocating the harmonious development of living environment and natural environment. 展开更多
关键词 Wild animals’ habitats ECOLOGICAL green lands Town-and-city CONCENTRATION area
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Environmental characteristics of anopheline mosquito larval habitats in a malaria endemic area in Iran 被引量:2
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作者 Moussa Soleimani-Ahmadi Hassan Vatandoost +4 位作者 Ahmad-Ali Hanafi-Bojd Mehdi Zare Reza Safari Abdolrasul Mojahedi Fatemeh Poorahmad-Garbandi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第7期510-515,共6页
Objective:To determine the effects of environmental parameters of lanal habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran.Methods:This cross-sectional study was conducted during t... Objective:To determine the effects of environmental parameters of lanal habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran.Methods:This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method,the specimens were identified using a morphological-based key.Simultaneously with larvay collection,environmental parameters of the larval habitats including water current and turbidity,sunlight situation,and substrate type of habitats were recorded.Water samples were taken from breeding sites during lanal collection.Before collection of samples,the water temperature was measured.The water samples were analysed for turbidity,conductivity,total alkalinity,total dissolved solid.pH and ions including chloride,sulphate,calcium,and magnesium.Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance.Results:In total 2 973 lanae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters.They comprised of six species: An.dthali(53.21%),An.stephensi(24.22%),An.culicifacies(14.06%),An.superpictus(4.07%),An. turkhudi(3.30%),and An.apoci(1.14%).The most abundant species was An.dthali which were collected from all of the study areas.Larvae of two malaria vectors.An.dthali and An.stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water.The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates.The results indicated that there was a significant relationship between mean physicochemical parameters such as water temperature,conductivity,total alkalinity,sulphate,chloride, and mosquito distribution and abundance.Conclusions:The results of this study showed a correlation between certain environmental parameters and mosquito lanae abundance,and these parameters should be considered in planning and implementing larval control programs. 展开更多
关键词 ANOPHELES LARVAL habitats MALARIA Rudan Iran
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Variations in diet composition of sympatric Trachypithecus francoisi and Macaca assamensis in the limestone habitats of Nonggang, China 被引量:3
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作者 Qi-Hai Zhou Zhong-Hao Huang +1 位作者 Hua Wei Cheng-Ming Huang 《Zoological Research》 SCIE CAS CSCD 2018年第4期284-290,共7页
Comparative studies of sympatric species are essential for understanding behavioral and ecological adaptation as well as the mechanisms that can reduce resource competition to allow coexistence. Francois' langurs (T... Comparative studies of sympatric species are essential for understanding behavioral and ecological adaptation as well as the mechanisms that can reduce resource competition to allow coexistence. Francois' langurs (Trachypithecus francoisi) and Assamese macaques (Macaca assamensis) are sympatric primate species found in the limestone seasonal rainforests of Nonggang Nature Reserve, southwestern Guangxi, China. To explore their different adaptation strategies, we collected data on diet using scan sampling at 15-min intervals. Our results revealed that Francois' langurs showed a more flexible diet composition than Assamese macaques Francois' langurs increased dietary diversity and mature leaf consumption in response to seasonal scarcity of preferred young leaves and fruits, whereas Assamese macaques relied heavily on young bamboo leaves (Indocalamus calcicolus) in most months These variations reflect the differences in digestive physiology, morphology, and the temporal and spatial distribution of food resources. 展开更多
关键词 Francois' iangurs Assamese macaques Diet composition Limestone habitat
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Comparison of intestinal bacterial communities in grass carp,Ctenopharyngodon idellus,from two different habitats 被引量:16
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作者 倪加加 余育和 +1 位作者 张堂林 高雷 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第5期757-765,共9页
The intestinal bacteria of vertebrates form a close relationship with their host.External and internal conditions of the host,including its habitat,affect the intestinal bacterial community.Similarly,the intestinal ba... The intestinal bacteria of vertebrates form a close relationship with their host.External and internal conditions of the host,including its habitat,affect the intestinal bacterial community.Similarly,the intestinal bacterial community can,in turn,influence the host,particularly with respect to disease resistance.We compared the intestinal bacterial communities of grass carp that were collected from farm-ponds or a lake.We conducted denaturing gradient gel electrophoresis of amplified 16S rRNA genes,from which 66 different operational taxonomic units were identified.Using both the unweighted pair-group method with arithmetic means clustering and principal component analysis ordination,we found that the intestinal bacterial communities from the two groups of pond fish were clustered together and inset into the clusters of wild fish,except for DF-7,and there was no significant correlation between genetic diversity of grass carp and their intestinal bacterial communities(Mantel one-tailed test,R=0.157,P=0.175).Cetobacterium appeared more frequently in the intestine of grass carp collected from pond.A more thorough understanding of the role played by intestinal microbiota on fish health would be of considerable benefit to the aquaculture industry. 展开更多
关键词 denaturing gradient gel electrophoresis grass carp habitat intestinal bacterial community
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Effects of of Habitats and Pesticides on Aerobic Capacity and Survival of Soil Fauna 被引量:2
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作者 G. TRIPATHI B. M. SHARMA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第3期169-175,共7页
Objective Faunal health is largely dependent on their soil environment and available litter quality. So the effects of different soil habitats and pesticides on citrate synthase (CS) activity of soil fauna and its pop... Objective Faunal health is largely dependent on their soil environment and available litter quality. So the effects of different soil habitats and pesticides on citrate synthase (CS) activity of soil fauna and its population were studied. Methods The soil animals were collected from different pedoecosystems for habitat study. Whereas Vigna radiata based system was selected for pesticidal observations. The field was divided into five equal plots for control and treatment of γ-BHC, quinalphos, carbaryl and cypermethrin. Soil fauna was collected by quadrat method and extracted by Tullgren funnel. Individuals of a species having similar sizes were collected for the estimation of CS activity. They were homogenized and fractions were obtained by differential centrifugation. The activity of CS was assayed spectrophotometrically. Results Citrate synthase (CS) activity of beetle (Rasphytus fregi), woodlouse (Porcellio laevis) and centipede (Scolopendra morsitans) varied significantly with respect to changes in different soil habitats. Though the CS activity of R. fregi, P. laevis, and S. morsitans differed among themselves but the highest activity of CS in these animals was in V. radiata and lowest in A. nilotica based pedoecosystem. The aerobic capacity of centipede was maximum followed by woodlouse and beetle. The treatment of γ-BHC, quinalphos, carbaryl and cypermethrin significantly reduced the CS activity of these animals. γ-BHC showed maximum reduction in CS activity indicating highly toxic effect of organochlorine on aerobic metabolism of soil fauna. However, minimum reduction was observed in response to carbaryl (in beetle) or cypermethrin (in woodlouse/centipede) leading to impairment of aerobic capacity. The differences in pesticide effects might be assigned to the differences in chemical nature of pesticides and their interactions with below-ground fauna. Treatment of γ-BHC and quinalphos reduced the population of Acari, Coleoptera, Collembola, other arthropods as well as total soil fauna. Acari was least affected by γ-BHC and maximally affected (72%) in response to quinalphos. The effect of γ-BHC was fairly similar on Coleoptera, Collembola, other arthropod and total soil fauna suggesting almost similar sensitivity to this pesticide. Likewise, quinalphos was similarly effective on Collemobola and other soil arthropods. Application of carbaryl decreased Acari and Coleoptera population but increased Collembola, other arthropods and total faunal populations. However, application of cypermethrin significantly reduced the population of Acari, Coleoptera, Collembola and total soil fauna and increased the population of other soil arthropods. In both the cases, acarine population was least affected. Conclusion The observations show the habitat-specific variation in aerobic capacity of soil fauna. However, pesticide-dependent loss in population might be due to impairment of aerobic capacity of soil inhabiting animals in desert. 展开更多
关键词 Citrate synthase habitat PESTICIDE Soil fauna and desert
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Habitat values for artificial oyster (Crassostrea ariakensis) reefs compared with natural shallow-water habitats in Changjiang River estuary 被引量:7
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作者 全为民 郑麟 +1 位作者 李备军 安传光 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期957-969,共13页
Oyster reefs have an equivalent, complex 3-dimensional structure to vegetated habitats and may provide similar functions in estuarine environments. Nevertheless, few studies have compared oyster reefs with adjacent na... Oyster reefs have an equivalent, complex 3-dimensional structure to vegetated habitats and may provide similar functions in estuarine environments. Nevertheless, few studies have compared oyster reefs with adjacent natural shallow-water habitats. Here the resident benthic macroinvertebrate communities in an artificial oyster (Crassostrea ariakensis) reef and in adjacent natural estuarine shallow-water habitats (salt marsh, intertidal mudflat, and subtidal soft bottom) in the Changjiang (Yangtze) River estuary were described. The mean total densities and biomass, Margalef's species richness, Pielou's evenness and Shannon-Weaver biodiversity indices of the resident benthic macroinvertebrate communities differed significantly among the habitats. Significantly higher densities and biomass of benthic macroinvertebrates occurred in the oyster reef compared with the other three habitats. Ordination plots showed a clear separation in benthic macroinvertebrate communities among the four habitat types. The results demonstrated that the artificial oyster reef supported distinct and unique benthic communities, playing an important role in the complex estuarine habitat by supplying prey resources and contributing to biodiversity. In addition, the results suggested that the oyster reef had been restored successfully. 展开更多
关键词 oyster reef habitat complexity biodiversity MACROINVERTEBRATES estuaries Changjiang River
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The possibility analysis of habitats,origin and reappearance of bloom green alga(Enteromorpha prolifera) on inshore of western Yellow Sea 被引量:12
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作者 丁兰平 费修绠 +2 位作者 陆勤勤 邓蕴彦 连绍兴 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期421-424,共4页
Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible w... Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide. 展开更多
关键词 bloom green alga Enteromorpha prolifera ORIGIN habitats reappearance western Yellow Sea
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Larval habitats of mosquito fauna in Osogbo metropolis,Southwestern Nigeria 被引量:1
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作者 Monsuru Adebayo Adeleke Wasiu Olalekan Adebimpe +4 位作者 Abdulwasiu Oladele Hassan Sunday Olukayode Oladejo IsmailOlaoye Ganiyu Olatunji Olatunde Taiwo Adewole 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期673-677,共5页
Objective:To determine the larval habitats of mosquito fauna and possible impact of land use/land cover changes on the epidemiology of mosquito-bome diseases in Osogbo metropolis,Southwestern,Nigeria.Methods:All acces... Objective:To determine the larval habitats of mosquito fauna and possible impact of land use/land cover changes on the epidemiology of mosquito-bome diseases in Osogbo metropolis,Southwestern,Nigeria.Methods:All accessible larval habitats were surveyed between May and September,2011in Osogbo metropolis while Land Use/Land cover of the city was analyzed using 2 Lansat Multispectral Scanner satellite imagery of SPOT 1986 and T.ANDSAT TM 2009.Results:A total of six species namely,Aedes aegypti,Aedes albopictus,Aedes vittatus,Anopheles gambiae complex,Culex quinquefascialus and Erelmapodite chrysogaster were encountered during the study.The occurrence and contribution of disused tyres was significantly higher(P<0.05)than the other habitats encountered,while there were no significant differences in the contribution of gutters/run-offs.septic tanks/drums,ground pools/open drains and discarded containers lo the breeding of mosquitoes(P>0.05).The accessible land use/land covered of the study area between 1986 and 2009 showed that the wet land coverage and settlement area increased from 0.19 lo 9.09 hectare and 1.00 to 2.01 hectare respectively while the forest area decreased from 60.18 to 50.14 hectare.Conclusion:The contribution of the habitats coupled with the increasing rale of flooded environment which could provide ample breeding sites for mosquitoes call for sustained environmental sanitation and management in Osogbo metropolis. 展开更多
关键词 LARVAL habitats MOSQUITOES LAND use/land cover NIGERIA
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Morphological Characteristics of the Dorsal Skin of Two Hynobiids and Their Adaptive Role in Aquatic and Terrestrial Habitats 被引量:1
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作者 Jianli XIONG Chongshan DAI +2 位作者 Mengyun LI Wen DENG Jichang LI 《Asian Herpetological Research》 SCIE 2013年第1期62-67,共6页
The morphological characteristics of the dorsal skin of trunk in two species of hynobiid salamanders, Batrachuperus pinchonii and Hynobius chinensis were examined by light microscopy. The basic structures of the skin ... The morphological characteristics of the dorsal skin of trunk in two species of hynobiid salamanders, Batrachuperus pinchonii and Hynobius chinensis were examined by light microscopy. The basic structures of the skin in the two species are similar and consist of two layers: epidermis and dermis. The epidermis consists of stratum corneum, stratum intermedium and stratum germinativum, while the dermis is composed of a stratum spongiosum and stratum compactum. However, some species-specific variation has been identified (e.g., the distribution of capillary vessels and gland cells, and the thickness of skin). H. chinensis is a terrestrial species and only lives in water during breeding period, but B. pinchonii is aquatic and remains aquatic throughout its lifetime. The differences in the distribution of capillary vessels and gland cells are related to their different habitats, and show a morphological adaptation. 展开更多
关键词 hynobiid salamander SKIN morphology ADAPTATION habitat
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Shifts in foraging behavior of wintering Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China 被引量:2
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作者 Wenjing Wan Lizhi Zhou Yunwei Song 《Chinese Birds》 CSCD 2016年第3期167-173,共7页
Background: Wetland loss and degradation result in a reduction in the availability and quality of food for wintering waterbirds. Birds normally modify their foraging behavior to adapt to variations in food availabilit... Background: Wetland loss and degradation result in a reduction in the availability and quality of food for wintering waterbirds. Birds normally modify their foraging behavior to adapt to variations in food availability. In this study, we compared shifts in foraging behavior of Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China to understand the response of these cranes to changes in habitat.Methods: We investigated the food density and foraging behavior of Hooded Cranes in Shengjin Lake National Nature Reserve from November 2014 to April 2015. We used regression equations to describe the changes in food density. A total of 397 behavioral observations were used in the analyses of their foraging efforts. We fitted a candidate set of generalized mixed linear models to analyze the relationship of foraging efforts and food density. We used a method of information theory to guide the selection of the model and Akaike's Information Criterion to calculate the value of each model. The relationship between food density, disturbances and foraging behavior was illustrated using a generalized linear model.Results: Along with the temporal variation and exploitation of food biomass, the food density varied widely among foraging sites. During the early winter period, foraging efforts were more pronounced in the paddy fields and meadows but not significantly different among the three habitats. The cranes spent more foraging effort in the paddy fields and meadows during the middle stage and in the meadows and mudflats during the late winter. The results of the generalized linear model showed that food density and disturbances had different effects on the rate of foraging success during the winter, while the effect of foraging effort was not significant. Furthermore, the rate of feeding success was markedly affected by disturbances in the paddy fields. The combined action of food density and disturbances had a significant effect on the rate of foraging success in the meadows, while the effect of foraging effort was also not significant in three habitats.Conclusions: Changes in foraging behavior were significant in three habitats, which were affected by food density and disturbances. The rate of foraging success increased in the habitat with low food density and low disturbances to increase the foraging efficiency in the lake. With abundant food and a high level of disturbance, the rate of foraging success decreased to ensure more secure access to food. 展开更多
关键词 Food density Foraging behavior habitat quality Hooded Crane
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Non-tidal tilt and strain signals recorded at the Geodynamic Observatory Moxa,Thuringia/Germany 被引量:3
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作者 Th.Jahr 《Geodesy and Geodynamics》 2018年第3期229-236,共8页
Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the... Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the observatory building and laser-strain meters in the gallery. The question arises how non-tidal signals are displayed in the measured time series. The investigation of such signals which can be caused naturally or man-made, can result in different sensitivities for the various tilt- and strainmeter systems, e.g. regarding barometric pressure impacts and hydrological induced pore pressure effects. 展开更多
关键词 Tilt and strain observations non-tidal effects Man-made effects Pore-pressureInduced tilt and strain Geodynamic Observatory
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Bird species composition and diversity in habitats with different disturbance histories at Kilombero Wetland, Tanzania 被引量:1
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作者 Wilbard A. Ntongani Samora M. Andrew 《Open Journal of Ecology》 2013年第7期482-488,共7页
Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these... Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these habitats in many tropical wetlands. To effectively restore these natural grasslands and conserve avifaunal biodiversity, understanding of the relationships between habitat conditions and bird community structure are central. We used a combination of information from nearby villagers and field surveys to establish two important grassland habitats with low and high disturbance histories, and related the habitats to bird community structure. We surveyed a total of 119 sites in the two habitats to examine variation in the abundance, richness, diversity and composition of birds at Kilombero Wetland Tanzania. In total, 3049 individuals, 126 species, 88 genera and 45 families were recorded from Kilombero grasslands. Our results show that grasslands with low human disturbance had more number of bird species, genera, families and diversity (both ShannonWiener and Simpson) than the most disturbed grasslands atp 0.05) between low and highly disturbed grassland habitats suggesting that other factors including variety of foraging sites are important. This study confirms that the wetland grasslands of Kilombero are important for conservation of birds including rare and endemic species. It is recommended that anthropogenic disturbancesshould be minimized including control of fire, regulation of agricultural activities and population of cattle within the wetland system to restore and conserve biodiversity. 展开更多
关键词 Natural habitats Simplified Landscapes ANTHROPOGENIC DISTURBANCE Richness Biodiversity Kilombero Tanzania
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Spatiotemporal dynamics of ecological variation of waterbird habitats in Dongtan area of Chongming Island 被引量:5
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作者 范学忠 张利权 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第3期485-496,共12页
Based on Landsat TM images, we explored the pattern of variation of suitable waterbird habitats from 1990 to 2008 in the Dongtan area of Chongming Island at the Changjiang (Yangtze) River mouth. By applying our highly... Based on Landsat TM images, we explored the pattern of variation of suitable waterbird habitats from 1990 to 2008 in the Dongtan area of Chongming Island at the Changjiang (Yangtze) River mouth. By applying our highly accurate indicator model (R=0.999, P<0.01), we quantified the variations of fluctuation intensity for local waterbird habitats during 1990-2008, and for the main waterbird groups (Anatidae, Charadriidae, Ardeidae and Laridae) from 2006 to 2008, to evaluate the impact of habitat quantity change on the waterbird habitat status and the population dynamics of the different waterbird groups. The results show that the aquaculture ponds (AP) and the Scirpus mariqueter zone (SMZ) underwent drastic habitat changes during certain periods (AP: 1997-2000, 2000-2003, 2005-2008; SMZ: 1997-2000), and the fluctuation intensity differed among habitat types in the order AP>SMZ>TSH (total suitable habitat)>BSA (bare mud flat and shallow water area). The abandonment of tracts of aquaculture ponds in Dongtan in mid-2006 brought about an intensive population fluctuation, caused by rapidly changing habitat with the population expanding to adjacent areas. At present, Anatidae and Ardeidae are threatened in the Dongtan area with declining populations because of their very "picky" habitat requirements (i.e., high reliance on AP). The Charadriidae experienced enormous population declines in the late 1990s, however, they have since recovered to normal levels as habitat change has stabilized. Our findings suggest that the current challenges for habitat management are the protection and stabilization of AP and SMZ habitats. 展开更多
关键词 WATERBIRD BIODIVERSITY habitat management population dynamics nature reserve Chongrning Island Changjiang (Yangtze) River estuary
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