Influence of environmental factors on the characteristics of macrobenthic communities in soft bottoms around coral reefs of Larak Island (Persian Gulf)

Assessment of macrobenthic communities of rocky intertidal zone from Zhejiang offshore islands with AZTI marine biotic index

Interactions of habitat complexity and environmental characteristics with macrobenthic community structure at multiple spatial scales in the northeastern Chukchi Sea

East Taihu Lake watershed has complex water functional areas; though it is small, human activities on the East Taihu Lake watershed environment interference are relatively strong. In this study, we investigated the diversity of macrobenthic communities and analyzed the pivotal environmental factors affecting alterations in the macrobenthic communities of East Taihu Lake. This analysis was augmented by controlled laboratory simulation experiments designed to elucidate and validate the responses of critical indicator species within various functional areas to environmental shifts. This study showed that (1) 28 species of macrobenthos were collected in the study area, belonging to 3 phyla, 6 orders, 13 orders, 18 families, and 25 genera. The mean values of annual macroinvertebrate density and biomass were 70.93 ± 42.92 ind/m2 and 50.99 ± 36.50g/m2. Bellamya purificata, Limnodrilus, and Tubifex were the dominant species on a year-round scale. Water depth and sediment water content were the most important environmental factors affecting the macrobenthic communities; (2) simulation experiments revealed that the growth condition of Bellamya was significantly worse in the simulated entrance area than in the simulated original enclosure aquaculture and wetland areas. The growth of Radix auricularia was significantly better in the presence of aquatic plants than in the absence of plants, and was more significantly influenced by environmental factors closely related to aquatic plants. The densities of annelids were significantly higher in the treatment group without plants than in that with plants, generally showing the growing trend of the simulated original enclosure aquaculture area > the simulated entrance area > the simulated wetland area. The results of the study support an aquatic revegetation strategy dominated by submerged plant restoration, and recommend water level regulation in shallow lake areas to reduce the impact of water level fluctuations on benthic habitats.

The characteristics of macrobenthic community structure can accurately indicate the ecological health of aquatic environments. To elucidate the spatiotemporal responses of macrobenthic communities and environmental factors in reservoirs, this study investigated macrobenthos and environmental parameters in Yinghu Lake during spring (May), summer (August), and autumn (November). The results showed that the trophic level index (TLI), total nitrogen (TN) and total phosphorus (TP) were significantly higher and pH was significantly lower (P < 0.05) at the developed sites (DS) than at the undeveloped sites (UDS). The survey identified 32 macrobenthos species representing 3 phylums and 5 orders. PERMANOVA analyses showed that the macrobenthic community structure of Yinghu Lake differed significantly between regions, Limnodrilus hoffmeisteri from the gathering collectors (20.47%) and Corbicula fluminea from the filtering collectors (7.82%) were the primary species driving the differences. The results of the two-way ANOVA indicated that species richness, the Margalef index (D), and the functional feeding group Margalef index (FFG-D) were significantly lower in summer than in autumn (P < 0.05). FFG-D was also significantly lower at the DS compared to the UDS (P < 0.05), while the interaction effects of season and region on these indicators were not significant (P > 0.05). Redundancy analysis (RDA) and generalized additive modelling (GAM) indicated that the permanganate index (CODMn) and total dissolved solids altered the macrobenthic community structure towards oligochaete and gathering collectors-dominated assemblages. Moreover, macrobenthic diversity was constrained by high total dissolved solids concentrations, sediment organic carbon (OC_s), soluble reactive phosphorus (SRP), low sediment total phosphorus (TP_s), high water temperature, and deep water. In summary, the spatiotemporal variations in water quality and macrobenthos communities in the reservoir were influenced by natural conditions and anthropogenic disturbances. This study provides valuable insights into the spatiotemporal dynamics of macrobenthic communities and contributes to a more comprehensive understanding of the role of biodiversity in maintaining the stability of large reservoir ecosystems.

The impact of suspended oyster farming on macrobenthic community in a eutrophic, semi-enclosed bay: Implications for recovery potential

Bay ecosystems with unique economic and ecological value are more vulnerable to heavy metal pollution than other marine ecosystems. In South Korea, rapid economic development has exacerbated heavy metal pollution in bay environments. This study analyzed concentrations of seven heavy metals and the structure of macrobenthic community in Asan Bay. Five heavy metal indices (PLI, Pn, RI, TRI, and MERMQ) were used to assess ecological risk. Additionally, spearman correlation, biota–environment matching (BIO-ENV), and redundancy analysis (RDA) were utilized to determine the influence of heavy metals on macrobenthic communities. Although average concentrations of seven heavy metals were below sediment quality guidelines (SQGs), the average concentration of Cd was close to the threshold effects level (TEL). The nemerow pollution index (Pn) and the potential ecological risk index (RI) indicated that Cd was the primary heavy metal contributing to ecological risk. Spearman correlation, BIO-ENV, and RDA indicated that heavy metals were the main environmental factors influencing macrobenthic communities in Asan Bay. However, five heavy metal indices (PLI, Pn, RI, TRI, and MERMQ) did not show a response to the macrobenthic communities. Overall, low concentrations of heavy metals have a certain negative impact on macrobenthic communities in Asan Bay. This study can serve as an important reference for marine environmental protection and policy-making in Asan Bay.

Unraveling the functional diversity of macrobenthic community from Prydz Bay, Indian sector of the Southern Ocean

对珠海鹤洲水道沿岸围垦湿地的4个红树人工林（包括老鼠簕<em>Acanthus ilicifolius</em>、木榄<em>Bruguiera gymnorrhiza</em>、秋茄<em>Kandelia candel</em>和无瓣海桑<em>Sonneratia apetala</em>）样地和2个挺水植被样地（短叶茳芏<em>Cyperus malaccensis</em> var. <em>brevifolius</em>和芦苇<em>Phragmites australis</em>）的大型底栖动物群落进行为期1a的生物调查。利用大型多元分析软件Primer 5的等级聚类分析CLUSTER（基于Bray-Curtis相似性矩阵）和非参数多变量标序NMDS分析大型底栖动物的群落结构，鹤州北围垦湿地6种生境下大型底栖动物在非相似度55%的条件下被划分为3组（组1：短叶茳芏-老鼠簕-木榄组合；组2：无瓣海桑组合；组3：秋茄-芦苇组合）。组1栖息地其大型底栖动物以谭氏泥蟹（<em>Ilyrplax deschampsi</em>）和多毛类为主，其中老鼠簕样地大型底栖动物物种数目（19种）、物种丰富度（<em>d</em>=1.93±0.11）和多样性指数（<em>H’</em>=1.51±0.13）均为全部6种生境最高；短叶茳芏样地的栖息密度（（254.67±156.81）个/m²）在6种生境中最高。组2栖息地其大型底栖动物以攀援型螺类和无齿螳臂相手蟹（<em>Chiromantes dehaani</em>）为主，生物量（（32.06±19.62）g/m²）在6种生境中最高，物种丰富度（<em>d</em>=1.28±0.45）和多样性指数（<em>H’</em>=1.04±0.27）居中。组3栖息地其大型底栖动物以麦克碟尾虫（<em>Discapseudes mackiei</em>）和多毛类为主，物种数、栖息密度、生物量和多样性指数均较低。SIMPER相似性百分比分析显示对群落划分起重要作用的物种主要为各个生境的优势物种。使用典范对应分析（CCA）对大型底栖动物分布与盐度、深度和温度3个环境因子的关系进行深入分析，并利用蒙特卡罗置换检验（Monte Carlo Permutation Test）鉴定环境因子的显著水平，其中盐度（<em>P</em> < 0.05）和深度（<em>P</em> < 0.05）与大型底栖动物分布差异显著相关，温度（<em>P</em> > 0.05）无显著相关。研究结果表明：不同生境大型底栖动物优势物种存在差异；盐度和深度是影响鹤州北围垦湿地大型底栖动物群落结构最重要的环境因子；围垦区人工湿地与自然滩涂大型底栖动物群落结构差异显著。;Macrobenthic communities were sampled four times over a one year period between December 2010 and September 2011 at six different sites in North Hezhou, Zhuhai, China. The six sites comprised four restored mangrove forest habitats (each dominated by a different mangrove species: <em>Acanthus ilicifolius</em>, <em>Bruguiera gymnorrhiza</em>, <em>Kandelia candel</em> and <em>Sonneratia apetala</em>) and two diked wetland habitats, one of which was composed of <em>Cyperus malaccensis </em>var. <em>brevifolius</em>, and the other <em>Phragmites australis</em>. In total, 35 macrobenthic species were recorded during the study. The dominant taxa recorded were crustaceans (10 taxa) and polychaetes (7 taxa). The number of species recorded at a single site varied from 7 (<em>Kandelia candel</em> habitat) to 19 (<em>Acanthus ilicifolius</em> habitat). Hierarchical clustering (based on the Bray-Curtis similarity index) combined with non-metric multidimensional scaling (NMDS); implemented in PRIMER 5 under the condition of 55% non-similarity), was used to classify sampling sites into three groups based on their macrobenthic fauna. Group 1 comprised <em>Cyperus malaccensis </em>var. <em>brevifolius, Acanthus ilicifolius</em>, and <em>Bruguiera gymnorrhiza </em>habitats; Group 2 comprised the <em>Sonneratia apetala</em> habitat; while Group 3 comprised <em>Kandelia candel</em> and <em>Phragmites australis</em> habitat. However, species composition was similar across all three groups, because <em>Discapseudes mackiei </em>was abundant at all six habitats. The highest number of species (19), highest Margalef index (<em>d</em> = 1.93±0.11), and highest species diversity (Shannon-wiener index, <em>H'</em> = 1.51±0.13)were recorded at the <em>Acanthus ilicifolius </em>habitat, where crustaceans, mainly <em>Ilyrplax deschampsi</em>, were the dominant group recorded. Macrobenthos density was highest at the <em>Cyperus malaccensis </em>var. <em>brevifolius </em>habitat (254.67±156.81) ind./m², while macrobenthos biomass was highest at the <em>Sonneratia apetala</em> habitat (32.06±19.62) g/m²). Interestingly, the faunal community structure at the <em>Sonneratia apetala</em> habitat differed significantly to the other habitats, as it was dominated by climbing species, such as <em>Chiromantes dehaani</em> and <em>Pythia cecillei</em>. <em>Discapseudes mackiei </em>and polychaetes were the dominant species within<em> Kandelia candel </em>and<em> Phragmites australis </em>habitats. Overall, macrobenthos species richness, density, biomass and species diversity were low within all six habitats. We also classified macrobenthic community structure based on functional feeding groups (FFGs) and life form analyses. Results showed that the omnivorous functional feeding group and below-surface life forms were abundant at all habitats within the North Hezhou tidal flat. Similarity percentages analysis (SIMPER) showed that the species that differentiated the macrobenthic communities of different habitats were the dominant species in each habitat. The results of a canonical correspondence analysis (CCA) revealed that macrobenthic communities changed significantly with depth (Monte Carlo permutation test: <em>P</em> < 0.05) and salinity (<em>P</em> < 0.05), but not with temperature (<em>P</em> > 0.05). The findings of this study suggest that macrobenthic communities differ structurally between the diked wetland habitats and the natural tidal flat habitats, with the highest densities and biomasses of macrobenthos occurring at habitats close to the tidal gate. Our results further reveal significant differences in the dominant species of macrobenthos occurring in different habitats. Furthermore, our results show that environmental variables, such as depth and salinity, are the most important factors affecting macrobenthic communities in the North Hezhou tidal flat.

Influence of two non-indigenous plants on intertidal macrobenthic communities in Ximen Island Special Marine Protected Area, China

Macrobenthic community in the Douro estuary: relations with trace metals and natural sediment characteristics

ABSTRACTArtificial reefs enhance marine biodiversity by increasing habitat complexity and heterogeneity, which in turn provide living space for various marine species. Macrobenthos, an important component of aquatic ecosystems, with limited mobility and sensitivity to environmental changes, commonly serve as indicators of aquatic ecosystem health. This study, conducted in the summer and autumn of 2022 in Sishili Bay (SB) and the Changdao Archipelago (CA), Yantai, China, aimed to evaluate the effects of artificial reefs on macrobenthic community structure using functional trait analysis. The nonmetric multidimensional scaling (nMDS) analysis based on species abundance and occurrence frequency did not reveal any clear separation between areas inside and outside the artificial reefs. However, the construction of artificial reefs increased the species number of macrobenthos, especially the Mollusca species. Feeding type, a key functional trait, distinguished areas inside and outside artificial reefs, with significant spatial and temporal variations. The key species driving differences between reef and nonreef areas include the carnivorous Lumbrineris longifolia and Glycinde bonhourei and the omnivorous Eriopisella sechellensis and Sigambra bassi, which were pivotal in the observed variations in relative abundance. Functional richness (FRic) and species richness (S) showed consistent patterns of variation, both contributing to improving the community stability in summer. However, in autumn, community stability was reduced by the extraordinary dominance of a single species. Multiple environmental factors rather than a single one significantly influenced species distribution and diversity, reflecting the complex interplay of reefs and seasonal dynamics. This study used functional trait analysis to assess the impact of artificial reefs on macrobenthic community structure, offering a more effective measure than species‐level assessments.

Tributaries flowing naturally play an important role in maintaining the biodiversity of aquatic organisms in dammed rivers. The Chishui River is currently the only undeveloped first-level tributary and an important habitat for aquatic organisms in the upper reaches of the Yangtze River. Understanding the distribution of the community structure of macrobenthos in the Chishui River and its influencing factors is crucial for the conservation and restoration of aquatic biodiversity in both the Chishui River and the Yangtze River. This study analyzes the community structure characteristics of macrobenthos in the Chishui River using four indicators, i.e., Margalef richness index, EPT taxon richness (the number of taxa in the pollution-sensitive Ephemeroptera, Plecoptera, and Trichoptera), Simpson dominance index, and Shannon diversity index, examining differences among different types of environmental factors (physical, chemical, and biological) in the upper, middle, and lower reaches. Subsequently, RDA (Redundancy Analysis) is used to analyze the main influencing factors of different types of environmental factors on macrobenthic community structure. VPA (Variance Partitioning Analysis) is employed to assess the relative importance of different types of environmental factors and their joint effects on the characteristics of macrobenthic community structure. The results indicate that physical environmental factors explain 68.7% of the variation in macrobenthic community structure indicators, chemical environmental factors explain 79.3%, and biological environmental factors account for 36.2%. The interaction among chemical, biological, and physical factors is the most significant explanatory variable, accounting for 41.7% of the variation in macrobenthic community structure characteristics. For EPT taxon number and Shannon diversity index, the interaction among chemical, biological, and physical factors is also the most important explanatory variable, accounting for 42.1% and 42.5% of the variation. For the Margalef richness index and Simpson dominance index, the interaction between chemical and physical factors is the most significant, accounting for 45.0% and 85.3% of the variation. Therefore, the impact of multiple environmental factors on aquatic organisms should not be overlooked, and attention should be paid to the contributions of various environmental factors in the conservation of macrobenthos in the Chishui River Basin.

Impact of dam operations on bottom sediment and macrobenthic community in the Kurobe Coast over a quarter century.

Research on the biodiversity of mangrove ecosystems should include not only the plants but other components, such as the macrobenthos. In order to understand the response of the macrobenthos to a mangrove habitat with high organics and nutrients, we compared the mangrove and non-mangrove macrobenthic communities, and analyzed their spatial-temporal distributions in these two habitats from April 2006 to January 2007 in Tong’an Bay, Fujian. Six sampling stations were set in Tong’an Bay, four of them (FL1, FL2, XA-A and XA-B) were in the mangrove habitat, the other two (FL3 and XA-C) were in the non-mangrove habitat. An analysis of sediment properties showed that total organic matter (TOM) of the three sampling stations at Fenglin exceeded the critical threshold, namely 3.4%, and TOM in mangrove stations was higher than in the non-mangrove ones. A total of 91 macrobenthic taxa were obtained from the six sampling stations in Tong’an Bay, including 77 and 67 taxa from the mangrove and non-mangrove habitats, respectively. Mean macrobenthic densities in the mangrove and non-mangrove habitats were 4,445.8 inds/m and 1,707.2 inds/m, respectively. Mean biomasses in the mangrove and non-mangrove habitats were 51.1 g/m and 94.6 g/m, respectively. The results of an independent-samples t-test showed that mean density and mean biomass were significantly different in the two habitats. The present study revealed that the mangrove habitat has a positive influence on the Oligochaeta, such as Limnodriloides sp., that thrives in the high TOM sediments. 第 1 期 周细平等: 福建同安湾潮间带红树林生境与非红树林生境大型底栖动物群落比较 61 Because of the shorter inundation period in the mangrove habitat, however, free-living molluscs and crustaceans preferred the non-mangrove habitat. Other sediment properties such as interstitial salinity and median particle diameter also affected the macrobenthic community.

To analyze the influences of genetic and environmental factors on smoking behavior, smoking cessation and onset age of smoking less than 20 years in male twin adults. A face-to-face questionnaire was conducted to collect data from 6 458 pair male twins aged ≥25 years registered in 9 provinces(municipality)in China. The heritability of three smoking related behaviors were calculated by using structural equation models. The ACE models were the best models of the three dimensions of smoking, i.e. smoking behavior, smoking cessation and onset age of smoking less than 20 years for male twins, and the corresponding heritability of these behaviors were 0.26(0.19-0.34), 0.27(0.19-0.37)and 0.05(0.00-0.14), respectively. When adjusted for area and age, the heritability of these three behaviors were 0.26(0.19-0.34), 0.31(0.00-0.74)and 0.05(0.00-0.14), respectively. All the three smoking related behaviors were affected by genetic factors, but environment factors had more effect on them. For smoking cessation, the heritability was highest, but the influence of environmental factors was lowest. Meanwhile, for onset age of smoking, the influence of environmental factors was highest.