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The environment effect on fish assemblage structure in waters adjacent to the Changjiang(Yangtze) River estuary(1998-2001) 被引量:22
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作者 于海成 线薇微 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期443-456,共14页
We collected fish abundance data in the Changjiang(Yangtze River) estuary and adjacent waters in November 1998,May 1999,November 2000,and May 2001.Using the data,we evaluated the characteristics of the fish assemblage... We collected fish abundance data in the Changjiang(Yangtze River) estuary and adjacent waters in November 1998,May 1999,November 2000,and May 2001.Using the data,we evaluated the characteristics of the fish assemblages at each site and investigated the effect of several environmental factors.We used a multivariate analysis,including community ordination methods such as detrended correspondence analysis(DCA) and canonical correspondence analysis(CCA),and two-way indicator species analysis(TWINSPAN).We analyzed the biological community structure and environmental factors to determine their spatial distributions,temporal dynamics,and seasonal variations.Among the fish species,five exceeded 5% of the total abundance:Harpodon nehereus(42.82%),Benthosema pterotum(13.85%),Setipinna taty(11.64%),Thryssa kammalensis(9.17%) and Apogonichthys lineatus(6.49%).These were separated into four ecological assemblages:hypsithermal-saline,hypsithermal-brackish,hypothermal-brackish,and hypothermal-saline.We evaluated the degree of influence of environmental factors on the fish community.Our analyses suggested that environmental factors including water depth,salinity,turbidity,transparency,nutrient,and suspended matter formed a synthetic spatial gradient between the coastal and pelagic areas.Ecological and environmental factors changed temporally from 1998 to 2001,and drove the fish community succession.The environmental factors driving the fish community structure included bottom temperature,water depth,bottom and surface pH,surface total phosphorous,and bottom dissolved oxygen.This investigation was completed before completion of the Three Gorges Dam;therefore the results of this study provide an important foundation for evaluating the influence of the human activities. 展开更多
关键词 fish assemblage structure environmental factors multivariate analysis Changjiang (Yangtze River) estuary
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Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters 被引量:1
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作者 单秀娟 金显仕 袁伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期459-469,共11页
Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and Oct... Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and October 2006. Four fish assemblages were identified in each survey using two-way indicator species analysis (TWIA). High fish biomass was found in the northern part, central part and coastal waters of the survey area; in contrast, high fish diversity was found in the southern part of the survey area and the Changjiang estuary outer waters. Therefore, it is difficult to maintain high fishery production when high fish diversity is evenly distributed in the fish community. Fish became smaller and fish size spectra tended to be narrower because of fish species variations and differences in growth characteristics. Fish diversity increased, the age to maturity was reduced and some migrant species were not collected in the surveys. Fish with low economic value, small size, simple age structure and low tropic level were predominant in fish assemblages in the Changjiang estuary and its adjacent waters. The lowest hypoxic value decreased in the Changjiang estuary and its adjacent waters. 展开更多
关键词 the Changjiang estuary fish assemblage structure diversity size spectrum
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Spatial and temporal variation of fish assemblages in a subtropical small stream of the Huangshan Mountain 被引量:12
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作者 Yunzhi YAN Shan HE +3 位作者 Ling CHU Xiuying XIANG Yanju JIA Juan TAO 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第6期670-677,共8页
Spatial and temporal variation of fish assemblages were investigated seasonally from May 2007 to February 2008 across 11 study sites in a subtropical small stream, the Puxi Stream, of the Huangshan Mountain. Along the... Spatial and temporal variation of fish assemblages were investigated seasonally from May 2007 to February 2008 across 11 study sites in a subtropical small stream, the Puxi Stream, of the Huangshan Mountain. Along the longitudinal gradient from headwater to downstream, fish species richness and abundance increased gradually, but then decreased significantly at the lower reaches. The highest species richness and abundance were observed in August and the lowest in February. Based on analysis of similarities (ANOSIM), fish assemblages were significantly different in spatial variation but not in temporal variation. Although differences were observed both among sites and among stream orders, the lower R value in order-variation suggested stream order was not the optimal factor explaining the spatial variation of fish assemblages. In addition, dam construction did not significantly alter fish assemblages in the sites adjacent to and immediately downstream to dams. Using cluster analysis and non-metric Multi Dimensional Scaling analysis (NMS), assemblages were separated into three groups at a Bray-Curtis similarity value of 42%: the upper, middle and lower groups. Following analysis of similarity percentages of species contributions (SIM- PER), shifts in occurrence or abundance of S. curriculus, Z. platypus, R. bitterling and A. fasciatus contributed most to the differences amongst the three groups. Standard Deviation Redundancy Analysis (RDA) suggested that habitat structure (such as elevation, substrate, and flow velocity) contributed to the spatial and temporal pattem of fish assemblages in the Puxi Stream. In conclusion, the fish assemblages in Puxi Stream presented significant spatial but not temporal variation. Human disturbance has perhaps induced the decrease in species diversity in the lower reaches. However, no significant change was observed for fish assemblages in sites far from and immediately downstream from low-head dams [Current Zoology 56 (6): 670-677, 2010]. 展开更多
关键词 assemblage structure Low-head dam Stream fish Spatial-temporal pattem
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Structural features of crust-mantle assemblage in the lithosphere along the Longitudinal Seismic Belt of China and their tectonic effect
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作者 毛桐恩 刘占坡 +3 位作者 徐常芳 张洪魁 余素荣 雷孟京 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期55-62,共8页
The 1°×1° distribution map of crustmantle structural ratio R for the lithosphere along the Longitudinal Seismic Belt of China has been compiled using computer based on the results of geophysical prospec... The 1°×1° distribution map of crustmantle structural ratio R for the lithosphere along the Longitudinal Seismic Belt of China has been compiled using computer based on the results of geophysical prospecting by previous researchers, and the latest results by the present authors. Based on this map, an insight into the structural features of the crustmantle assemblage along the Longitudinal Seismic Belt has been gained, while their relation to seismic activity and the distributions of geothermal flux and intracrustal high conductivitylow velocity layers, as well as their tectonic effect to seismicity have been discussed. 展开更多
关键词 LITHOSPHERE Longitudinal Seismic Belt structural features of crustmantle assemblage tectonic effect high conductivitylow velocity layer
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Mechanism of Nutrient Silicon and Water Temperature Influences on Phytoplankton Growth 被引量:3
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作者 杨东方 高振会 +2 位作者 孙培艳 李梅 曲延峰 《Marine Science Bulletin》 CAS 2006年第2期49-59,共11页
This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of ... This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of phytoplankton growth and the different profiles of the change of its assemblage structure influenced by nutrient silicon and water temperature. Taking Jiaozhou Bay for example, this paper showed the process of both the variation of phytoplankton growth and the change of its assemblage structure, unveiled the mechanism of nutrient silicon and water temperature influencing the variation of phytoplankton growth and the change of its assemblage structure, and determined that nutrient silicon and water temperature were the motive power for the healthy running of the marine ecosystem. 展开更多
关键词 SILICON water temperature phytoplankton growth assemblage structure mechanism
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Solar light,seawater temperature,and nutrients,which one is more important in affecting phytoplankton growth? 被引量:4
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作者 苗振清 杨东方 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期825-831,共7页
Based on research results on the impacts of solar light,seawater temperature,and nutrient available to phytoplankton growth and changes in phytoplankton physiology and assemblage,we discussed the order of influence of... Based on research results on the impacts of solar light,seawater temperature,and nutrient available to phytoplankton growth and changes in phytoplankton physiology and assemblage,we discussed the order of influence of these factors.By clarifying the mechanisms and processes of the impacts by these factors,we have determined the rising order of the importance as solar light,seawater temperature,and nutrient silicon (Si).Therefore,for human interests in sustaining economic development,the first thing to be considered is the input of nutrient Si into the ocean,followed by seawater temperature change. 展开更多
关键词 solar light seawater temperature nutrient Si phytoplankton growth and assemblage structure order of importance
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Temporal dynamics of shallow subtidal meiobenthos from a beach in Tenerife (Canary Islands, northeast Atlantic Ocean)
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作者 Rodrigo Riera Jorge Núez María del Carmen Brito 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第8期44-54,共11页
A shallow subtidal (3 m deep) meiofaunal assemblage in Los Abrigos Bay, Tenerife, Canary Islands was sam- pled during May 2000-April 2001. The main aims were to (1) find temporal variations in meiofaunal assem- bl... A shallow subtidal (3 m deep) meiofaunal assemblage in Los Abrigos Bay, Tenerife, Canary Islands was sam- pled during May 2000-April 2001. The main aims were to (1) find temporal variations in meiofaunal assem- blage structure and overall abundance, as well as in the most abundant meiofaunal species throughout the study period, and (2) identify environmental variables (sedimentary composition, organic matter content, and total nitrogen) that better explain meiofaunal assemblage structure during the study year. The most abundant species were the nematodes Siphonolaimus sp. 2 and Catanema sp., which represented 46.2% of the overall meiofaunal abundances and varied significantly throughout the study duration. Overall meio- faunal abundance and the most abundant taxonomic groups (nematodes, copepods, and oligochaetes) showed significant temporal variations during the study period. Nematodes overwhelmingly dominated during the study period, ranging from 78% in May to 97.34% in February. Multivariate analyses showed seasonality in meiofaunal community structure during the study year, with the lowest abundances in May. Keywords: Meiofauna, assemblage structure, subtidal, Canary Islands, Atlantic Ocean 展开更多
关键词 MEIOFAUNA assemblage structure SUBTIDAL Canary Islands Atlantic Ocean
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Effect of scots pine forest management on soil properties and carabid beetle occurrence under post-fire environmental conditions——a case study from Central Europe
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作者 Ewa Błońska Bartłomiej Bednarz +2 位作者 Magdalena Kacprzyk Wojciech Piaszczyk Jarosław Lasota 《Forest Ecosystems》 SCIE CSCD 2020年第3期366-377,共12页
Background: Fires have a fundamental impact on phytocoenoses and, depending on the size of the fire, can have a positive or negative effect. The role of fires in the formation of the species composition of plants, res... Background: Fires have a fundamental impact on phytocoenoses and, depending on the size of the fire, can have a positive or negative effect. The role of fires in the formation of the species composition of plants, restoration of stands and changes in soil properties is well studied. However, the long-term relationship between forest management methods, soil properties and epigeic entomofauna assemblages in post-fire areas is still not clear. The effects of Scots pine stand management methods on biochemical soil properties and ground beetle assemblages in the largest post-fire area in Central Europe after the second World were investigated. The study was conducted in the Rudy Raciborskie Forest district in southern Poland. The soil properties and epigeic beetle community structure were analysed. The research covered areas with natural and artificial pine regeneration, which were subjected to various care treatments.Results: The tendency for higher accumulations of organic matter in the soil of stands that underwent natural regeneration was proven. The stimulating role of soil organic carbon on the activity of dehydrogenases in the soil of naturally renewed areas with silvicultural treatment(NRAT) was noted. Regardless of the manner of stand regeneration, the activity of β-glucosidase was higher in the areas in which breeding treatments were practised.Furthermore, managed forest stands presented a higher abundance of carabid beetles than stands without treatment practices. Thirteen epigeic beetle species from the families Geotrupidae, Carabidae, Curculionidae,Cerambycidae and Silphidae were captured, with beetles from the first two families being the most numerous. Rare epigeal carabid species in the fauna of Poland and Europe, such as Carabus glabratus(Paykull) and Carabus auronitens Fabr., found appropriate habitat conditions for survival in the post-fire areas. Compared with the other areas, in the NRAT area, there were better stand and soil properties and more features conducive to epigeic entomofaunal occurrences. The highest post-fire content of polycyclic aromatic hydrocarbons was recorded in the soils of the sites that underwent artificial regeneration. The results suggest that preparing the soil before the introduction of new vegetation affects the amount of aromatic hydrocarbons(PAHs).Conclusions: The better performance of the NRAT stand draws attention to the positive aspects of the use of natural regeneration, both from ecological and economic perspectives. The effects of forest management on the amount of soil organic matter after fires have been proven. The natural regeneration of stands was conducive to the accumulation of organic matter. The enzymatic activity of soils is influenced by the renewal method and forest management strategy. The NRAT area was characterized by the highest number of carabid species. 展开更多
关键词 Stand treatment strategy Forest regeneration Enzyme activity Soil organic carbon Epigeic beetle assemblage structure
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Functional and phylogenetic structure of mammals along elevational gradients in the Central and East Himalayas
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作者 Yiming Hu Zhifeng Ding +5 位作者 Huijian Hu Luke Gibson Dan Liang Zhixin Zhou Jianchao Liang Brett R.Schefers 《Ecological Processes》 2024年第4期51-66,共16页
Background Mountain ecosystems are critical hotspots of global biodiversity,yet the dynamics of community assembly along their elevational gradients are not well understood.This gap is primarily due to the complexity ... Background Mountain ecosystems are critical hotspots of global biodiversity,yet the dynamics of community assembly along their elevational gradients are not well understood.This gap is primarily due to the complexity of environmental and biotic interactions that influence species distribution and community structure.Although extensive research has been conducted on certain taxa,such as small mammals and bats,comprehensive stud-ies encompassing entire mammal assemblages are lacking.Our research aims to bridge this gap by examining the taxonomic,phylogenetic,and functional diversity,as well as the assemblage structures of mammal communities across elevational gradients in the Central and East Himalayas,exploring how diverse ecological and evolutionary processes impact community assembly.Methods We analyzed mammal elevational diversity patterns using species richness,functional diversity(FD),and phylogenetic diversity(PD).We compared the observed values of community structure,such as mean pairwise phylogenetic distance(MPD)and mean pairwise functional distance(MFD),with null-model corrected effect sizes to identify patterns and processes of community assembly.Using structural equation modeling and hierarchical par-titioning,we investigated the relationships between climate,productivity,and various facets of diversity,describing the organization of each component across different elevations.Results Taxonomic,functional,and phylogenetic diversity generally decreased with elevation but showed var-ied patterns such as mid-elevation peaks,low-elevation plateaus,or monotonic declines across different regions.Richness-controlled functional diversity increased towards mid-low elevations and decreased at higher elevations in both regions,whereas richness-controlled phylogenetic diversity lacked consistent patterns.Phylogenetic struc-tures tended to cluster from mid to high elevations,indicating closer relationships than those observed in random communities,likely due to significant environmental turnover near tree lines.Functional structure showed greater clustering at high elevations and increased over-dispersion at lower elevations,suggesting that species are more functionally similar than expected at higher elevations and more diverse at lower elevations.Our results revealed that environmental factors,evolutionary histories,and trait-driven ecological processes collectively shape species rich-ness along these gradients.Conclusions Our results showed incongruent community structures across phylogenetic and functional diversity.Generally,functional traits are closely linked to environmental conditions,reducing the chance of observing traits that are misaligned with their surroundings.Species with similar ecological roles or distinct evolutionary lineages often show convergent adaptations to highland environments.Additionally,our fiindings emphasize that commu-nity assembly varies with the biogeography and diversification history of individual mountain ranges,complicating the development of a generalized theory.Using multiple measures is important for accurate community structure assessments and effective conservation planning,as variable elevational patterns exist across different diversity dimensions. 展开更多
关键词 assemblage structure Functional diversity Himalaya mountains Mammals Phylogenetic diversity Species richness
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