Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant spec...Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant species and the largest distribution areas of seagrass, yet the seagrass macrofauna in this region are poorly understood. To help fill this gap in our knowledge, an ecological survey was conducted to describe the abundance and diversity of benthic macrofauna from tropical seagrass beds and to determine between-station variations within a transect and between-site variations in macrofaunal abundance, taxa richness and community structure. Benthic macrofaunal samples associated with seagrass beds were collected with a core sampler on the east coast of North Sulawesi in May 2014 and on the west coast in October 2015. A total of 149 species from 14 higher taxa was collected. The most species-rich groups were polychaetes（56 species, 26% of total individual numbers）, decapods（20 species, 9% of total numbers） and amphipods（18 species, 35% of total numbers）. Between-station variations within a transect displayed different patterns between the east coast and the west coast. On the east coast, there were marked variations in abundance between stations within a transect for the macrofauna and amphipod assemblages. Both taxa richness and abundance varied with station for the macrofauna and polychaete assemblages on the west coast, resulting from the heterogeneity of the substrate along a transect. One-way ANOSIM together with MDS ordination indicated that macrofaunal community structure in seagrasses differed significantly between the east coast and the west coast, corresponding with the division of seagrasses into two broad categories of habitats, i.e.,mangrove-seagrass-reef continuum and seagrass-reef continuum. Compared with other studies in tropical areas,the abundance and diversity of benthic macrofauna in the present study were moderate. The reason for the two markedly distinct macrofaunal communities might be attributed to multiple factors, including sediment pattern,seagrass structure and temporal changes.展开更多
Horizontal (geographic) and vertical (geonemic) spatial distribution of the integral properties of a large multispecies assemblage (1306 species of fish and invertebrate with body size ≥ 1 cm) from northwest Pacific ...Horizontal (geographic) and vertical (geonemic) spatial distribution of the integral properties of a large multispecies assemblage (1306 species of fish and invertebrate with body size ≥ 1 cm) from northwest Pacific sea bottom is investigated. There are total number and biomass, average animal size (mean individual weight), species diversity (Shannon’s index) and its components: species richness and evenness (Pielou’s index), i.e. generalized parameters describing benthic macrofauna as a whole. Correlations of these parameters with distance from shore and depth have been found as well as very weak latitudinal zonality display in the region. Even such well-known generalization as Humboldt-Wallace’s law and Bergman’s rule has no noticeable manifestations here. Earlier similar, but not identical, regularities were discovered in the northwest Pacific pelagic water layer. Collation of what there is in the two different sea zones results in new supplements to Zenkevich-Bogorov’s concept of biological structure of the ocean.展开更多
Sediment and macrobenthic fauna distribution at Dar es Salaam harbour channel were investigated to attest the influence of sediment grain size distribution and total organic carbon contents on benthic macrofauna domin...Sediment and macrobenthic fauna distribution at Dar es Salaam harbour channel were investigated to attest the influence of sediment grain size distribution and total organic carbon contents on benthic macrofauna dominance and diversity. Sampling campaign was conducted from January to April, 2019 in 25 sampling stations along the channel. Sediment grain sizes ranged between 0.7405 and 0.00273 mm with an average of 0.0804 mm classified as medium silt. Sediment distribution showed an onshore-offshore pattern consisting of fine dark clay-silt sediments in the southern part of the harbour close to Mwalimu Nyerere Bridge, medium (sandy) at the harbour and coarse sandy offshore. Five classes of macrofauna were identified with sedentary Polychaetes (Diopatra cuprea) found in tubes and free forms being dominant in most of the sediment types, however more abundant in clay-silt. High species diversity index values were encountered in sediments with medium total organic carbon (TOC) and sediment grain sizes (sand-silt). Apparently, low species similarity indices were observed in all sediment type indicating significant dissimilarities in species composition among sediment grain sizes. Thus, the distribution of benthic macrofauna species along Dar es Salaam harbour channel is strongly influenced by the sediment grain sizes and organic carbon contents in sediments.展开更多
In order to compare the macrozoobenthic community and sedimentary environment with and without the presence of horseshoe crabs,the benthic macrofauna,sediment grain size,chromium(Cr),cobalt(Co),nickel(Ni),polycyclic a...In order to compare the macrozoobenthic community and sedimentary environment with and without the presence of horseshoe crabs,the benthic macrofauna,sediment grain size,chromium(Cr),cobalt(Co),nickel(Ni),polycyclic aromatic hydrocarbon(PAHs),organic carbon and nitrogen were seasonally investigated at site A(with horseshoe crab presence),sites B and C(without horseshoe crab presence)in the Crocodile Island intertidal zone in Xiamen from June 2018 to July 2019.The results showed that most of the community parameters of benthic macrofauna,population parameters of common benthic macrofauna and environmental parameters were significantly different at the sites with horseshoe crab versus non-horseshoe crab sites.A two-way ANOVA test showed that the densities of Ceratonereis erythraeensis and Sigambra hanaokai had significant site variation.Cluster and nonmetric multi-dimensional scaling(NMDS)analysis showed the community composition of benthic macrofauna was significantly different among the three sampling sites over four seasons.The mean sand content at site A(64.32%)was higher than those at site B(36.01%)and site C(18.86%).Conversely,the mean contents of silt,clay,Cr,Co,Ni,organic carbon,organic nitrogen,phenanthrene,and pyrene at site A were lower than those at site B and site C.These observations are consistent with the expected preferences of horseshoe crabs to live in areas with 60%sand content,which is associated with abundant and edible clamworms in the Crocodile Island intertidal zone,Xiamen.展开更多
The ecological environment in the Yellow Sea has changed greatly from the 1950s to 1990s and this has had significant impact on marine organisms. In this study, data on soft-sediment macrobenthos occurring in depths f...The ecological environment in the Yellow Sea has changed greatly from the 1950s to 1990s and this has had significant impact on marine organisms. In this study, data on soft-sediment macrobenthos occurring in depths from 25 m to 81 m in the South Yellow Sea were used to compare changes in community structure. The agglomerative classification (CLUSTER) and multidimensional scaling (MDS) methods were applied. Five communities were recognized by cluster analysis: 1. The Yellow Sea Cold Water Mass community dominated by cold water species, which changed slightly in species composition since the 1950s; 2. The mixed community with the coexistence of cold water species and warm water species, as had been reported previously; 3. The polychaete-dominated eurythermal community in which the composition changed considerably as some dominant species disappeared or decreased; 4. The Changjiang (Yangtze) River Estuarine community, with some typical estuarine species; 5. The community affected by the Yellow Sea Warm Current. The greatest change occurred in the coastal area, which indicated that the change may be caused by human activities. Macrobenthos in the central region remained almost unchanged, particularly the cold water species shielded by the Yellow Sea Cold Water Mass. The depth, temperature and median grain size of sediments were important factors affecting the distributions of macrobenthos in the South Yellow Sea.展开更多
The present study analyses the spatio-temporal variability of the macrozoobenthos from the intertidal zone of the Kneiss Islands (Gulf of Gabès, Tunisia). Samples were collected once from 34 stations, while seaso...The present study analyses the spatio-temporal variability of the macrozoobenthos from the intertidal zone of the Kneiss Islands (Gulf of Gabès, Tunisia). Samples were collected once from 34 stations, while seasonal variations were studied by sampling four times at 12 stations over the period 2013-2014. A total of 159 macrobenthos taxa associated with intertidal Zostera noltei beds are identified from the 34 stations, with a taxonomic dominance of crustaceans (32%), molluscs (29%) and annelids (27%). Abundance varies from 9244 to 36,844 ind·m<sup>-2</sup> with a mean value of 14,346 ind·m<sup>-2</sup>. Analysis of the trophic structure shows that the majority of stations are strongly represented by carnivores (41%), followed by the non-selective deposit feeders (16%). Cluster analysis and multidimensional scaling allow identification of three main benthic assemblages based on species abundance, corresponding to different sediment types and organic matter contents. The seasonal variability in abundance, diversity and community structure is mainly due to spring and summer recruitment. The biotic indices (i.e. AMBI, BO2A and BENTIX) show that the intertidal area of Kneiss Islands exhibits a good ecological status.展开更多
This study presents a biotic index （∧） for measuring environmental quality in the coastal lagoons of the Mediterranean. Index A considers combined anthropogenic （pollution） and natural factors （prohibitive salin...This study presents a biotic index （∧） for measuring environmental quality in the coastal lagoons of the Mediterranean. Index A considers combined anthropogenic （pollution） and natural factors （prohibitive salinity, anoxia, toxic blooms, isolation from sea, etc.） of deterioration. The method is based on the principle of indicator species and on the conceptual scheme developed by Frisoni et al. （1984） according to which there are six possible sub-assemblages （Zones） of benthic macrofauna, each indicating a different level of environmental quality. The procedure requires defining the relative extent of the Zones in the lagoon under study, and the number of species and the mean biomass of benthic macrofauna present in each. The three metrics are applied in the index formula and the resulting number from one to ten indicates increasing environmental quality. The authors have validated the index by applying it to two lagoons, Lesina and Varano （S.Adriatic, Italy）.展开更多
基金China-Indonesia Maritime Cooperation Fund Project“China-Indonesia Bitung Joint Marine Ecological Station Establishment”the Scientific Research Foundation of Third Institute of Oceanography,SOA under contract No.2011034
文摘Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant species and the largest distribution areas of seagrass, yet the seagrass macrofauna in this region are poorly understood. To help fill this gap in our knowledge, an ecological survey was conducted to describe the abundance and diversity of benthic macrofauna from tropical seagrass beds and to determine between-station variations within a transect and between-site variations in macrofaunal abundance, taxa richness and community structure. Benthic macrofaunal samples associated with seagrass beds were collected with a core sampler on the east coast of North Sulawesi in May 2014 and on the west coast in October 2015. A total of 149 species from 14 higher taxa was collected. The most species-rich groups were polychaetes（56 species, 26% of total individual numbers）, decapods（20 species, 9% of total numbers） and amphipods（18 species, 35% of total numbers）. Between-station variations within a transect displayed different patterns between the east coast and the west coast. On the east coast, there were marked variations in abundance between stations within a transect for the macrofauna and amphipod assemblages. Both taxa richness and abundance varied with station for the macrofauna and polychaete assemblages on the west coast, resulting from the heterogeneity of the substrate along a transect. One-way ANOSIM together with MDS ordination indicated that macrofaunal community structure in seagrasses differed significantly between the east coast and the west coast, corresponding with the division of seagrasses into two broad categories of habitats, i.e.,mangrove-seagrass-reef continuum and seagrass-reef continuum. Compared with other studies in tropical areas,the abundance and diversity of benthic macrofauna in the present study were moderate. The reason for the two markedly distinct macrofaunal communities might be attributed to multiple factors, including sediment pattern,seagrass structure and temporal changes.
文摘Horizontal (geographic) and vertical (geonemic) spatial distribution of the integral properties of a large multispecies assemblage (1306 species of fish and invertebrate with body size ≥ 1 cm) from northwest Pacific sea bottom is investigated. There are total number and biomass, average animal size (mean individual weight), species diversity (Shannon’s index) and its components: species richness and evenness (Pielou’s index), i.e. generalized parameters describing benthic macrofauna as a whole. Correlations of these parameters with distance from shore and depth have been found as well as very weak latitudinal zonality display in the region. Even such well-known generalization as Humboldt-Wallace’s law and Bergman’s rule has no noticeable manifestations here. Earlier similar, but not identical, regularities were discovered in the northwest Pacific pelagic water layer. Collation of what there is in the two different sea zones results in new supplements to Zenkevich-Bogorov’s concept of biological structure of the ocean.
文摘Sediment and macrobenthic fauna distribution at Dar es Salaam harbour channel were investigated to attest the influence of sediment grain size distribution and total organic carbon contents on benthic macrofauna dominance and diversity. Sampling campaign was conducted from January to April, 2019 in 25 sampling stations along the channel. Sediment grain sizes ranged between 0.7405 and 0.00273 mm with an average of 0.0804 mm classified as medium silt. Sediment distribution showed an onshore-offshore pattern consisting of fine dark clay-silt sediments in the southern part of the harbour close to Mwalimu Nyerere Bridge, medium (sandy) at the harbour and coarse sandy offshore. Five classes of macrofauna were identified with sedentary Polychaetes (Diopatra cuprea) found in tubes and free forms being dominant in most of the sediment types, however more abundant in clay-silt. High species diversity index values were encountered in sediments with medium total organic carbon (TOC) and sediment grain sizes (sand-silt). Apparently, low species similarity indices were observed in all sediment type indicating significant dissimilarities in species composition among sediment grain sizes. Thus, the distribution of benthic macrofauna species along Dar es Salaam harbour channel is strongly influenced by the sediment grain sizes and organic carbon contents in sediments.
基金the National Key Research and Development Program of China(No.2016YFC0502904)。
文摘In order to compare the macrozoobenthic community and sedimentary environment with and without the presence of horseshoe crabs,the benthic macrofauna,sediment grain size,chromium(Cr),cobalt(Co),nickel(Ni),polycyclic aromatic hydrocarbon(PAHs),organic carbon and nitrogen were seasonally investigated at site A(with horseshoe crab presence),sites B and C(without horseshoe crab presence)in the Crocodile Island intertidal zone in Xiamen from June 2018 to July 2019.The results showed that most of the community parameters of benthic macrofauna,population parameters of common benthic macrofauna and environmental parameters were significantly different at the sites with horseshoe crab versus non-horseshoe crab sites.A two-way ANOVA test showed that the densities of Ceratonereis erythraeensis and Sigambra hanaokai had significant site variation.Cluster and nonmetric multi-dimensional scaling(NMDS)analysis showed the community composition of benthic macrofauna was significantly different among the three sampling sites over four seasons.The mean sand content at site A(64.32%)was higher than those at site B(36.01%)and site C(18.86%).Conversely,the mean contents of silt,clay,Cr,Co,Ni,organic carbon,organic nitrogen,phenanthrene,and pyrene at site A were lower than those at site B and site C.These observations are consistent with the expected preferences of horseshoe crabs to live in areas with 60%sand content,which is associated with abundant and edible clamworms in the Crocodile Island intertidal zone,Xiamen.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-YW-417)
文摘The ecological environment in the Yellow Sea has changed greatly from the 1950s to 1990s and this has had significant impact on marine organisms. In this study, data on soft-sediment macrobenthos occurring in depths from 25 m to 81 m in the South Yellow Sea were used to compare changes in community structure. The agglomerative classification (CLUSTER) and multidimensional scaling (MDS) methods were applied. Five communities were recognized by cluster analysis: 1. The Yellow Sea Cold Water Mass community dominated by cold water species, which changed slightly in species composition since the 1950s; 2. The mixed community with the coexistence of cold water species and warm water species, as had been reported previously; 3. The polychaete-dominated eurythermal community in which the composition changed considerably as some dominant species disappeared or decreased; 4. The Changjiang (Yangtze) River Estuarine community, with some typical estuarine species; 5. The community affected by the Yellow Sea Warm Current. The greatest change occurred in the coastal area, which indicated that the change may be caused by human activities. Macrobenthos in the central region remained almost unchanged, particularly the cold water species shielded by the Yellow Sea Cold Water Mass. The depth, temperature and median grain size of sediments were important factors affecting the distributions of macrobenthos in the South Yellow Sea.
文摘The present study analyses the spatio-temporal variability of the macrozoobenthos from the intertidal zone of the Kneiss Islands (Gulf of Gabès, Tunisia). Samples were collected once from 34 stations, while seasonal variations were studied by sampling four times at 12 stations over the period 2013-2014. A total of 159 macrobenthos taxa associated with intertidal Zostera noltei beds are identified from the 34 stations, with a taxonomic dominance of crustaceans (32%), molluscs (29%) and annelids (27%). Abundance varies from 9244 to 36,844 ind·m<sup>-2</sup> with a mean value of 14,346 ind·m<sup>-2</sup>. Analysis of the trophic structure shows that the majority of stations are strongly represented by carnivores (41%), followed by the non-selective deposit feeders (16%). Cluster analysis and multidimensional scaling allow identification of three main benthic assemblages based on species abundance, corresponding to different sediment types and organic matter contents. The seasonal variability in abundance, diversity and community structure is mainly due to spring and summer recruitment. The biotic indices (i.e. AMBI, BO2A and BENTIX) show that the intertidal area of Kneiss Islands exhibits a good ecological status.
文摘This study presents a biotic index （∧） for measuring environmental quality in the coastal lagoons of the Mediterranean. Index A considers combined anthropogenic （pollution） and natural factors （prohibitive salinity, anoxia, toxic blooms, isolation from sea, etc.） of deterioration. The method is based on the principle of indicator species and on the conceptual scheme developed by Frisoni et al. （1984） according to which there are six possible sub-assemblages （Zones） of benthic macrofauna, each indicating a different level of environmental quality. The procedure requires defining the relative extent of the Zones in the lagoon under study, and the number of species and the mean biomass of benthic macrofauna present in each. The three metrics are applied in the index formula and the resulting number from one to ten indicates increasing environmental quality. The authors have validated the index by applying it to two lagoons, Lesina and Varano （S.Adriatic, Italy）.
