A field experimental study on recolonization and succession of macrobenthic infauna in defaunated sediment contaminated with petroleum hydrocarbons

A field experiment was carried out in Hong Kong to study the patterns of recolonization and succession of subtidal macrobenthos in defaunated sediment contaminated with petroleum hydrocarbons and to determine the time required for benthic recovery from petroleum contamination. A total of 31 species was found and 83 animals/tray and 14 species/tray on an average were recorded after one month. Initial colonization was dominated by polychaetes in both abundance and species number (accounting for 69.1% and 64.5%, respectively). Abundance of macrobenthos came to a small crest (308 animals/tray) after three months, reached a sharp peak (1257 animals/tray) after six months, and then declined to a steady level. Abundance, species number and diversity in the petroleum-contaminated sediment were significantly lower than those in the control sediment in the early successional stages, indicating deleterious effects of petroleum hydrocarbons on recolonization and succession of macrobenthos. Petroleum hydrocarbons in sediment significantly altered species composition of macrobenthos in recolonization and succession. No significant differences in community parameters and species composition between the petroleum-contaminated and the control communities were found after 11 months, indicating that macrobenthic community had recovered from petroleum contamination.     

枸杞岛贻贝养殖区大型底栖动物群落结构及与环境因子的关系

大型底栖动物物种组成及其群落结构能间接反映贻贝养殖区底栖生态状况。基于2021年4月和8月枸杞岛贻贝养殖区现场调查数据,开展了大型底栖动物群落结构、季节差异及主要驱动因子的系统解析。调查共鉴定大型底栖动物172种,隶属14纲40目84科,物种季节更替率为83.14%。丰度等级分布(Rank abundance)曲线表明,夏季物种更丰富,但均匀度相对较低。春、夏季大型底栖动物Shannon-Wiener多样性介于1.61～2.95之间,季节间差异显著。Simpson指数与盐度、沉积物中值粒径(D50)存在显著正相关关系;生物量与沉积物中值粒径、总有机碳(TOC)存在显著负相关关系;物种数、Chao1指数、生物量、丰富度均与TOC显著负相关。聚类分析将春季分为四个组别,夏季分为三个组别,NMDS分析表明,春季分组物种分离不显著,夏季分组物种分离显著,相似性分析(ANOSIM)印证了这种差异。应用相似百分比(SIMPER)分析表明,季节平均相异率为87.57%,分歧种为丝异须虫(Heteromastus filiformis)。CCA分析表明,溶解氧、TOC和硝酸盐是驱动贻贝养殖区大型底栖动...     

Local and temporal variations in near‐shore macrobenthic communities associated with submarine groundwater discharges

The influence of submarine groundwater discharges (SGD) on the dynamics of coastal ecosystems is receiving increasing scientific attention, although our knowledge of this issue still remains insufficient. Understanding the ecological response of coastal ecosystems to SGD dynamics is important in order to evaluate and predict changes in coastal communities. The aim of the present study was to characterize the effect of groundwater discharge on subtidal soft‐bottom macrofaunal assemblages in the south coast of Portugal (Algarve) at different times of the year and under different discharge regimes. Sediment macrofauna was sampled twice per season in spring and summer 2011 in two locations: one under influence of SGD (Olhos de Água) and one not under that influence (Arrifes). The results showed that differences in community structure between locations occurred mainly during spring, when the magnitude of groundwater discharge was higher. Several individual taxa were strongly associated with the SGD, particularly during spring: the polychaete families Magelonidae and Oweniidae; the isopod Cyathura carinata; and the bivalves Tellimya ferruginosa and Tellina fabula. Some of these taxa are already considered indicators of SGD, whereas others merit further investigation. The average similarity among samples was consistently larger in the location with SGD and the average similarity between the two locations was generally higher during spring, indicating that SGD promote stability in macrobenthic communities across time and space. SGD were also associated with higher values of Chlorophyll a (Chl a), fine sediments and total abundance of organisms (particularly suspension feeders). This suggests that differences between locations are associated with SGD and mediated by nutrient fluxes and sediment transport, or their interaction.     

胶州湾红石崖潮间带大型底栖动物群落生态学研究

根据2003年8月至2004年5月(夏、秋、冬、春季)4个季度月,对位于胶州湾内红石崖潮间带的高潮带(H1站)、中潮带(H2站)、和低潮带(H3站)所设的3个站进行了综合生态调查并分析所获的资料。结果表明,红石崖潮间带大型底栖动物的总平均栖息密度、总平均生物量和总种数分别为718.67个/m2、123.21g/m2和62种。平均密度、平均生物量和种数在高潮带分别是1765.5个/m2、342.53g/m2和12种;中潮带分别是248个/m2、11.31g/m2和35种;低潮带分别是142.5个/m2、15.74g/m2和44种。3个潮带的平均密度(D):大小顺序为DH1>DH2>DH3,平均生物量(B):BH1>BH3>BH2;种数(S):SH3>SH2>SH1。定性采集在3个潮区共采到大型底栖动物44种,其中有27种在定量采集中没采到,3个潮带共采到大型底栖动物89种。     

2016—2019年长江口海域季节性低氧对大型底栖动物群落的影响

基于2016—2019年夏季在长江口海域进行的4个航次的生态环境调查,分析了长江口海域季节性低氧对大型底栖动物群落结构的影响。结果表明,2016—2019年长江口海域夏季底层DO最低值为1.51 mg/L,存在不同程度的底层低氧现象。低氧区与非低氧区之间大型底栖动物的种类数量、丰度、生物量和群落结构均存在显著差异。多毛类表现出对低氧较强的耐受能力,为低氧区的主要优势类群,中蚓虫(Mediomastus sp.)、索沙蚕(Lumbrinereis sp.)为低氧区的主要优势种。软体动物、甲壳动物和棘皮动物的分布趋势则与多毛类相反,其中甲壳动物对低氧的耐受能力较弱。MDS多维尺度排序表明,低氧区与非低氧区之间大型底栖动物的群落组成差异明显;CCA分析表明,长江口海域夏季底层低氧已对大型底栖动物的群落结构产生一定程度的影响。     

大亚湾大型底栖动物群落特征与生态质量评价研究

开展近岸海域大型底栖动物多样性调查和生态质量评价对于指导海洋生态环境保护修复具有重要意义。本研究以广东省大亚湾为研究区域,于2022年8月进行大型底栖动物和环境因子调查,利用生物指数AMBI和M-AMBI对大亚湾底栖动物群落健康状况和生态质量状况进行评价。本研究共采集到大型底栖动物69种,环节动物为优势类群,主要优势种为多鳃齿吻沙蚕(Nephtys polybranchia)、细丝鳃虫(Cirratulus filiformis)和奇异稚齿虫(Paraprionospio pinnata),与历史资料对比研究表明,近40年来,大亚湾大型底栖动物物种组成已经发生显著变化。典范对应分析表明,亚硝酸-氮(NO₂-N)和硝酸-氮(NO₃-N)是影响大型底栖动物群落丰度的主要环境因子,表明含氮营养盐已经对大亚湾大型底栖动物群落产生负面影响。生物指数评价结果表明,大亚湾底栖生境处于“未扰动”或“轻度扰动”状态,生态质量处于“好”或“一般”状态。     

长江口邻近海域大型底栖生物群落结构分析

2004年5月的调查共获大型底栖生物50种,种数和丰度的优势生物为多毛类动物,而底栖鱼类和螠虫的生物量占明显优势。长江口大型底栖生物平均生物量为17.57g/m2,平均丰度为150ind./m2。生物量和丰度密集区集中在盐度25度线附近海域。根据Bray-Curtis相似性系数聚类分析和多维排序尺度分析,长江口大型底栖生物可划分为四个群落:Ⅰ圆筒原盒螺-滩栖阳遂足-棘刺锚参-背蚓虫群落;Ⅱ圆筒原盒螺-钩虾群落;Ⅲ背蚓虫-奇异稚齿虫-不倒翁-尖叶长手沙蚕-近辐蛇尾群落;Ⅳ短叶索沙蚕-长吻沙蚕-纽虫群落。通过引入环境变量的二维MDS图分析,长江口大型底栖生物群落分布与底层盐度、有机物具有较大的相关性。生存环境短时间内的剧烈变化是导致群落Ⅱ和Ⅳ种群贫乏的重要原因之一。河口区悬浮粉砂颗粒的短期快速沉降现象可能也是导致群落Ⅱ和Ⅳ种群贫乏的另一重要原因。     

Marine and Brackish Ecosystems of South Brittany (Lorient and Vilaine Bays) with Particular Reference to the Effect of the Turbidity Maxima

The south Brittany coast of France offers considerable opportunities to study the transition between estuaries and the sea. The sea coast is semi-enclosed, due to the local geomorphology, with sheltered conditions. The infaunal macrobenthic communities have been identified and characterized by species richness (S), abundance (A) and biomass (B), related to environmental factors. The spatial succession of infauna along the estuarine gradient shows the presence of an area with a much reduced fauna, and an oligobiotic area with low values of S, A and B. In these strongly stratified estuaries, concentration of organic matter and sediment can result in oxygen depletion, which is not favourable for survival of the infauna. The oligobiotic area seems to be related to the presence of the turbidity maximum, the location and importance of which are functions of river discharge and hydrodynamic mixing. The turbidity maximum which causes these conditions is shown to be at a higher salinity than has previously been described for this phenomenon, and is shown to break the spatial gradient of marine to brackish communities which has been described in larger estuaries.     

Sandy beach ecosystems: key features, sampling issues, management challenges and climate change impacts

Escalating pressures caused by the combined effects of population growth, demographic shifts, economic development and global climate change pose unprecedented threats to sandy beach ecosystems worldwide. Conservation of beaches as functional ecosystems and protection of their unique biodiversity requires management interventions that not only mitigate threats to physical properties of sandy shores, but also include ecological dimensions. Yet, beach management remains overwhelmingly focused on engineering interventions. Here we summarise the key outcomes of several workshops, held during the 2006 Sandy Beach Ecology Symposium in Vigo, Spain, that addressed issues of climate change, beach management and sampling methodology. Because efficient communication between managers and ecologists is critical, we summarise the salient features of sandy beaches as functional ecosystems in 50 'key statements'; these provide a succinct synopsis of the main structural and functional characteristics of these highly dynamic systems. Key outcomes of the workshops include a set of recommendations on designs and methods for sampling the benthic infaunal communities of beaches, the identification of the main ecological effects caused by direct and indirect human interventions, the predicted consequence of climate change for beach ecosystems, and priority areas for future research.     

H'、AMBI和M-AMBI指数在黄河口及邻近海域底栖生境健康评价中的适宜性研究

From a dataset of macrobenthos obtained from 18 cruises from 2004 to 2013 in the Huanghe(Yellow River)Estuary and its adjacent areas,the composition and characteristics of macrobenthos were analyzed,and the applicability of the Shannon-Wiener Index(H′),AZTI's Marine Biotic Index(AMBI) and multivariate AMBI(MAMBI) for assessing benthic habitat quality was compared.The results showed a total of 203 macrobenthos in the study area.The macrobenthos were dominated by polychaetes,followed by mollusks and crustaceans.The macrobenthic ecological groups were dominated by EGI,EGII and EGIII,which respectively accounted for 31.5%,36.0% and 21.2% of the total.There were significant differences between the evaluation results of the three indices.The ecological quality status(EQS) levels given by the AMBI were greater than those given by the H′ and M-AMBI.The AMBI could not reflect the differences between 11 sites but the H′ and M-AMBI could do.Moreover,the three indices responded well to the variations in salinity(S) and dissolved oxygen(DO) in the waters.The H′ and MAMBI also responded sensitively to the differences in physical parameters,such as water depth and sediment texture.The correlation between M-AMBI and environmental pressure gradient data was the strongest.The MAMBI could effectively distinguish degraded conditions from undegraded but the H′ and AMBI could not.Therefore,the M-AMBI reflected benthic habitat health well in the study areas.However,the objectivity of evaluation results of M-AMBI needs further verification by physical,chemical and biological methods.The thresholds also need further discussion.