检索结果-南通市图书馆

Spatial and seasonal variations in the trophic spectrum of demersal fish assemblages in Jiaozhou Bay, China

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Oceanology and Limnology 2015年第4期33卷 934-944页

作者：韩东燕薛莹任一平麻秋云 Fisheries College Ocean University of China

trophic structure of fish communities is fundamental for ecosystem-based fisheries management, and trophic spectrum classifies fishes by their positions in food web, which provides a simple summary on the trophic structure and ecosystem function. In this study, both fish biomass and abundance trophic spectra were constructed to study the spatial and seasonal variations in the trophic structure of demersal fish assemblages in Jiaozhou Bay, China. Data were collected from four seasonal bottom trawl surveys in Jiaozhou Bay from February to November in 2011. trophic levels(TLs) of fishes were determined by nitrogen stable isotope analysis. This study indicated that most of these trophic spectra had a single peak at trophic level(TL) of 3.4–3.7, suggesting that demersal fish assemblages of Jiaozhou Bay were dominated by secondary consumers(eg. Pholis fangi and Amblychaeturichthys hexanema). The spatial and seasonal variations of trophic spectra of Jiaozhou Bay reflected the influence of fish reproduction, fishing pressure and migration of fishes. Two-way analysis of variance(ANOVA) showed that seasonal variations in trophic spectra in Jiaozhou Bay were significant(P 0.05). The trophic spectrum has been proved to be a useful tool to monitor the trophic structure of fish assemblages. This study highlighted the comprehensive application of fish biomass and abundance trophic spectra in the study on trophic structure of fish assemblages.

关键词： demersal fish assemblage trophic spectrum trophic structure stable isotope analysis Jiaozhou Bay

Seasonal variability in free-living marine nematode community structure in a sandy beach of the Taiping Bay of Qingdao,China

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2008年第2期27卷 102-115页

作者： LIU Haibin ZHANG Zhinan FAN Shiliang HUA Er DENG Ke College of Marine Life Science Ocean University of China Qingdao 266003 China Liaoeheng Agriculture Bureau Liaocheng 252000 China

Nematode assemblage composition, trophic structure and biodiversity were followed over an annual cycle in a sandy beach of the Taiping Bay of Qingdao, China. Nematode assemblage in the sandy beach maintained a high genus diversity （75 genera）. Mlero- laimus and Bathylaimus were the dominant genus of the nematode assemblage, accounting for 66% of the total nematode abundance. The nematodes＇ dominant trophic structure changed seasonally as a response to the seasonal changes in food quality. Epigrowth-feeder nematodes （2A） were the dominant trophic groups in the trophic structure with the highest abundance in spring because of phytoplankton bloom, while the feeding type （ 1 B） showed higher abundance in summer that was due to the increasing of sediment detritus after spring bloom. Furthermore, species diversity and evenness calculated on nematodes identified to the genus level displayed significant temporal changes, which was also reflected by the index of trophic diversity. According to the cluster analysis, the nematode community structure of the whole year was clearly separated into two periods （A and B）. Biota-Envlron- ment matching （BIOENV） results showed that seawater temperature, sediment Chl a and grain size were responsible for the nema- tode community structure variation in spring and summer period （Period A）. However, seawater/interstitial water temperature, interstitial water dissolved oxygen concentration,interstitial water salinity, and sediment Ph a a were more important in constructing the autumn and winter period （Period B） nematode community structure.

关键词： nematode assemblage composition trophic structure temporal change Taiping Bay of Qingdao

Nematode Community structure and Diversity Pattern in Sandy Beaches of Qingdao,China

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2016年第1期15卷 33-40页

作者： HUA Er MU Fanghong ZHANG Zhinan YANG Shichao ZHANG Ting LI Jia College of Marine Life Sciences Ocean University of China

We investigated the diversity and structure of free-living marine nematode communities at three sandy beaches representing typical intertidal environments of a temperate zone in Qingdao,Shandong Province,*** nematode abundance ranged from 1006 to 2170 ind.10 cm-2,and a total of 34 nematode genera were recorded,of which only 8 were common in all the studied ***'s evenness and Shannon-Wiener diversity index were the lowest at the second beach where nematode abundance was the *** highest species diversity index coincided with the lowest nematode abundance at Shilaoren *** median grain size,sorting coefficient,and chlorophyll-a content were essential for differentiation in nematode abundance and species diversity,whereas taxonomic diversity of nematode was homogeneous across the three *** 0–20 cm sediment profile,nematode abundance declined abruptly with depth,whereas nematode diversity changed gently with obvious difference in 16–20 cm *** granulometry and chlorophyll-a content were the two foremost factors which influenced the vertical distribution pattern of nematode generic ***-selective deposit feeders constituted the most dominant trophic group,followed by epistratum ***(family:Tripyloididae) dominated at the second and Yangkou beach,while Theristus(family:Xyalidae) prevailed at Shilaoren *** and predators became important at Shilaoren beach because of the high proportion of *** though,nematode community of the studied beaches did not differ significantly from each other.

关键词： vertical distribution biodiversity taxonomic diversity index trophic structure

trophic functioning of macrobenthic fauna in a tropical acidified Bornean estuary(Southeast Asia)

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2019年第1期34卷 48-57页

作者： Mohammad Belal Hossain Department of Fisheries and Marine Science Noakhali Science and Technology University

The trophic structure of a community is used to infer ecosystem functioning(e.g. energy transfer and nutrient cycling). Here the trophic structure of the benthic infaunal and epifaunal communities in the Brunei Estuary are characterized, and their distribution along an estuarine pH gradient is analyzed using univariate and multivariate techniques. This analysis revealed that surface deposit feeders(e.g., polychaetes) were numerically dominant within the infaunal communities whereas in the epifaunal communities filter feeders(e.g., bivalves) were highly abundant. Species richness for almost all trophic groups increased toward the lower estuary, except for omnivores in the epifaunal communities, which decreased markedly. Both Analysis of Variance(ANOVA) and Analysis of Similarities(ANOSIM) detected significant differences in the density of respective trophic groups among stations. Within infaunal communities, both Biological and Environmental procedure(BIO-ENV) and Canonical Correspondence Analysis(CCA) showed that trophic shifts were associated with environmental gradients. Surface-deposit feeders and omnivores were the most abundant macrobenthos of the upper estuary characterized by low salinity, low pH, and a higher percentage of mud particles. The proportion of filter feeders and carnivores increased with salinity/pH and sand. A more uniform distribution of trophic structure was found in the lower estuary, with high salinity and pH over sandy habitat. In contrast, within epifaunal trophic groups,the percentage of surface deposit feeders and omnivores declined, but filter feeders remarkably increased toward the sea. The proportion of carnivores remained similar at all stations. Non-Metric Multidimensional Scaling(nMDS) ordination for epifaunal trophic groups clearly demarcated higher salinity/pH stations from lower salinity/pH stations, suggesting different trophic compositions along the estuarine pH gradient.

关键词： Macrobenthic communities trophic structure Environmental factors Acidity Tropical estuary