Biodiversity and Habitat Assessment of Coastal Benthic Communities in a Sub-Arctic Industrial Harbor Area

Coastal ecosystems face increasing anthropogenic pressures worldwide and their management requires a solid assessment and understanding of the cumulative impacts from human activities. This study evaluates the spatial variation of benthic macrofaunal communities, sediments, and heavy metals in the sub-Arctic coastal ecosystems around Sept-Îles (Québec, Canada)—a major port area in the Gulf of St. Lawrence. Physical sediment properties varied in the studied area, with a general sandy-silty profile except for specific locations in Baie des Sept Îles where higher organic matter and heavy metal concentrations were detected. Macrofaunal assemblages were evaluated for two taxa size classes (organisms > 0.5 mm and > 1 mm) and linked to habitat parameters using regression models. Communities of smaller organisms showed signs of perturbation for one assemblage close to industrial activities at Baie des Sept Îles, with an increased number of tolerant and opportunistic species, contrasting to neighboring regions whose compositions were similar to other ecosystems in the Gulf of St. Lawrence. This study enhances the understanding of sub-Arctic benthic communities and will contribute to monitoring programs for industrial harbor ecosystems.

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Shallow sublittoral benthic communities of the Laguna Estuarine System, South Brazil

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592006000100004 ◽

2006 ◽

Vol 54 (1) ◽

pp. 41-54 ◽

Cited By ~ 15

Author(s):

Gustavo Fonseca ◽

Sérgio A. Netto

Keyword(s):

Species Richness ◽

Chlorophyll A ◽

Temporal Variability ◽

Benthic Communities ◽

Nematode Species ◽

Estuarine System ◽

Life Strategies ◽

Sediment Properties ◽

Higher Taxa ◽

South Brazil

Sediment properties, microphytobenthos biomass (chlorophyll a and phaeopigments), and the structure of the benthic communities of the three main lagoons (Mirim, Imaruí and Santo Antonio) of the Laguna Estuarine System, South Brazil, were analyzed during summer and winter. Microphytobenthos biomass did not differ significantly among the lagoons, but showed higher values in the summer. The macrofauna was characterized by low species richness and the dominance of the gastropod Heleobia australis, the tanaidean Kalliapseudes schubartti and the bivalve Erodona mactroides. The meiofauna was composed of 20 higher taxa and the nematodes dominated in all the lagoons and periods. Desmodora (Desmodora) sp.1, Terschllingia sp. and Microlaimus sp. were numerically the most important among the 74 nematode species registered. This study showed that, in the Laguna Estuarine System, differences in the benthos among lagoons and periods were dependent on the fauna component analyzed. Whilst macrofauna and nematodes were significantly more diverse in the inner stations, in the Mirim Lagoon, the number of meiofauna taxa did not differ significantly among the lagoons and the diversity and evenness were highest in Santo Antonio. These results were a response of the fauna to the salinity oscillations coupled with the heterogeneity of the sediment in the lagoons. The temporal variability of the fauna, macrofauna being more abundant in the summer and meiofauna in the winter, could be related to the different life strategies of these groups.

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Impact of a large-scale area closure on patterns of fishing disturbance and the consequences for benthic communities

ICES Journal of Marine Science ◽

10.1016/s1054-3139(03)00010-9 ◽

2003 ◽

Vol 60 (2) ◽

pp. 371-380 ◽

Cited By ~ 131

Author(s):

T.A Dinmore ◽

D.E Duplisea ◽

B.D Rackham ◽

D.L Maxwell ◽

S Jennings

Keyword(s):

North Sea ◽

Large Scale ◽

Fishery Management ◽

Benthic Communities ◽

Benthic Invertebrate ◽

Homogeneous Distribution ◽

Cumulative Impacts ◽

Management Actions ◽

Fishing Vessels ◽

Fishing Disturbance

Abstract Seasonal area closures of fisheries are primarily used to reduce fishing mortality on target species. In the absence of effort controls, fishing vessels displaced from a closed area will impact fish populations and the environment elsewhere. Based on the observed response of the North Sea beam trawl fleet to the closure of the “cod box” and an existing size-based model of the impacts of beam trawling, we predict the effects of seasonal area closures on benthic communities in the central North Sea. We suggest that repeated seasonal area closures would lead to a slightly more homogeneous distribution of annual trawling activity, although the distribution would remain patchy rather than random. The increased homogeneity, coupled with the displacement of trawling activity to previously unfished areas, is predicted to have slightly greater cumulative impacts on total benthic invertebrate production and lead to localized reductions in benthic biomass for several years. To ensure the effective integration of fisheries and environmental management, the wider consequences of fishery management actions should be considered a priori. Thus, when seasonal closures increase the homogeneity of overall disturbance or lead to the redistribution of trawling activity to environmentally sensitive or previously unfished areas, then effort reductions or permanent area closures should be considered as a management option. The latter would lead to a single but permanent redistribution of fishing disturbance, with lower cumulative impacts on benthic communities in the long run.

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Synergistic Effects of Rooted Aquatic Vegetation and Drift Wrack on Ecosystem Multifunctionality

Ecosystems ◽

10.1007/s10021-021-00609-9 ◽

2021 ◽

Author(s):

Å. N. Austin ◽

J. P. Hansen ◽

S. Donadi ◽

U. Bergström ◽

B. K. Eriksson ◽

...

Keyword(s):

Species Richness ◽

Vegetation Cover ◽

Aquatic Vegetation ◽

Synergistic Effects ◽

Experimental Studies ◽

Coastal Ecosystems ◽

Nitrogen Loading ◽

Predatory Fish ◽

Anthropogenic Pressures ◽

Ecosystem Multifunctionality

AbstractEcosystem multifunctionality is an increasingly popular concept used to approximate multifaceted ecosystem functioning, which in turn may help advance ecosystem-based management. However, while experimental studies have shown a positive effect of diversity on multifunctionality, observational studies from natural systems—particularly aquatic—are scarce. Here, we tested the relative importance of species richness and cover of rooted aquatic vegetation, as well as cover of the loose-lying form of the macroalgae bladderwrack (Fucus vesiculosus), for ecosystem multifunctionality in shallow bays along the western Baltic Sea coast. We estimated multifunctionality based on four indicators of functions that support ecosystem services: recruitment of large predatory fish, grazer biomass, inverted ‘nuisance’ algal biomass, and water clarity. Piecewise path analysis showed that multifunctionality was driven by high cover of rooted aquatic vegetation and bladderwrack, particularly when the two co-occurred. This synergistic effect was nearly three times as strong as a negative effect of land-derived nitrogen loading. Species richness of aquatic vegetation indirectly benefitted multifunctionality by increasing vegetation cover. Meanwhile, high bladderwrack cover tended to decrease vegetation species richness, indicating that bladderwrack has both positive and negative effects on multifunctionality. We conclude that managing for dense and diverse vegetation assemblages may mitigate effects of anthropogenic pressures (for example, eutrophication) and support healthy coastal ecosystems that provide a range of benefits. To balance the exploitation of coastal ecosystems and maintain their multiple processes and services, management therefore needs to go beyond estimation of vegetation cover and consider the diversity and functional types of aquatic vegetation.

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Marine benthic communities and anthropogenic activities in Sept-Îles (Canada): a peaceful coexistence?

10.7287/peerj.preprints.26737 ◽

2018 ◽

Author(s):

Elliot Dreujou ◽

Philippe Archambault ◽

Christopher W McKindsey

Keyword(s):

Human Activities ◽

Anthropogenic Activities ◽

Benthic Communities ◽

Industrial Wastes ◽

Cumulative Impacts ◽

Peaceful Coexistence ◽

Small Spatial Scale ◽

Cumulative Impact ◽

Cumulative Stress ◽

Benthic Ecosystems

With the development of coastal human activities comes the growing need to develop methods to describe their cumulative impacts on marine benthic communities at local geographic scales. Local assessments facilitate dialogue between multiple users of the ecosystem (industries, individuals) and allow to better understand variation among benthic communities in a given region. In this project, we aim to develop indicators of cumulative impacts to assess the environmental health of benthic ecosystems within industrialized regions in the Gulf of St. Lawrence at a small spatial scale (0.01 km2). We selected coastal regions around Sept-Îles, where numerous human activities are present at different intensities (such as international shipping, fisheries or domestic and industrial wastes). Subtidal ecosystems were sampled in 2016-2017 to characterize macro-endobenthic diversity and abiotic parameters of the sediment. We calculated impact scores for each human activity based on the distance from the source and the magnitude of its impact. We thus identified hotspots of cumulative impact and changes in the biotic and abiotic compartments along impact gradients. These results will be used for the development of indicators of cumulative stress and to understand resilience and stability of bay-scale benthic communities.

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Prediction Models for Evaluating the Uptake of Heavy Metals by the Invasive Grass Vossia cuspidata (Roxb.) Griff. in the River Nile, Egypt: A Biomonitoring Approach

Sustainability ◽

10.3390/su131910558 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10558

Author(s):

Emad A. Farahat ◽

Waleed F. Mahmoud ◽

Hossam E. A. Awad ◽

Hussein F. Farrag ◽

Muhammad Arshad ◽

...

Keyword(s):

Heavy Metals ◽

Regression Models ◽

Bioconcentration Factor ◽

Prediction Models ◽

Translocation Factor ◽

River Nile ◽

Invasive Grass ◽

Sediment Properties ◽

Zn And Cu In ◽

The Mean

This study aimed to develop new prediction models that include sediment properties (pH, organic matter, and silt and clay concentrations) for estimating the potential uptake of heavy metals (HMs) by the invasive grass Vossia cuspidata. Plant and sediment samples were collected from the microsites that represent the natural distribution of the species in two Nile islands in Cairo, Egypt. The results show that the root was the main accumulating organ for the analyzed HMs (Fe, Mn, Zn, Cu, Ni, and Pb). The mean concentrations of Fe and Mn and the maximum concentrations of Cu, Ni, and Pb were phytotoxic. The values of the bioconcentration factor were >1, while the translocation factor was >1 for Zn and Cu in rhizome and stem, Mn in leaf, and Ni and Pb in stem and leaf. There were no significant differences between the measured and the predicted HM concentrations in all organs of the species. This indicates the excellent robustness of the developed regression models. Sixteen equations (out of 24) had high R2 values. Thus, V. cuspidata could be considered a biomonitor for HM pollution, and the developed equations will benefit the prediction of HM uptake by the species in the River Nile ecosystem.

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Detection of Ecological Thresholds and Selection of Indicator Taxa for Epibenthic Communities Exposed to Multiple Pressures

Frontiers in Marine Science ◽

10.3389/fmars.2021.720710 ◽

2021 ◽

Vol 8 ◽

Author(s):

Laurie Isabel ◽

David Beauchesne ◽

Chris McKindsey ◽

Philippe Archambault

Keyword(s):

Benthic Communities ◽

Marine Ecosystem ◽

Anthropogenic Pressures ◽

Eastern Canada ◽

Management Tools ◽

Indicator Taxa ◽

Multiple Pressures ◽

Concentration Threshold ◽

The Impact ◽

Epibenthic Communities

The estuary and the Gulf of St. Lawrence (EGSL), eastern Canada form a vast inland sea that is subjected to numerous anthropogenic pressures. Management tools are needed to detect and quantify their effect on benthic communities. The aims of this study are to analyze the spatial distribution of epibenthic communities in the EGSL and quantify the impact of important pressures on them to identify indicator taxa. Epibenthic communities were sampled at 1314 EGSL sites between 2011 and 2018 by bottom trawling. Cluster analyses revealed the presence of six distinct epibenthic communities that seem to be strongly influenced by oxygen concentration. Threshold analyses confirm that oxygen is an important predictor of epibenthic community composition and distribution. A major oxygen threshold is observed around 50–100 μmol O2 L–1, resulting in a shift of community type. At these concentrations and below, opportunistic taxa dominate the community while sensitive taxa are absent or present at very low abundance. Biomass of the latter only starts to increase when oxygen concentrations reach 150 μmol O2 L–1. The species Actinostola callosa, Actinauge cristata, Ctenodiscus crispatus, and Brisaster fragilis were identified as good indicators for detecting this impact threshold forepibenthic communities. This study provides threshold-based indicator species that help to establish and monitor the ecological state of epibenthic communities in a marine ecosystem exposed to multiple pressures.

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Hard-Bottom Megabenthic Communities of a Chilean Fjord System: Sentinels for Climate Change?

Frontiers in Marine Science ◽

10.3389/fmars.2021.635430 ◽

2021 ◽

Vol 8 ◽

Author(s):

Federico Betti ◽

Francesco Enrichetti ◽

Giorgio Bavestrello ◽

Andrea Costa ◽

Alessandra Moreni ◽

...

Keyword(s):

Best Management Practices ◽

Management Practices ◽

Benthic Communities ◽

Detailed Examination ◽

Anthropogenic Pressures ◽

Marine Fauna ◽

Best Management ◽

Fjord System ◽

Underwater Photography ◽

Environmental Status

Chilean Patagonia hosts one of the extensive fjord systems in the world, spanning more than 1,600 km between 41 and 55°S, and with a complex geomorphology and hydrography that supports rich and unique assemblages of marine fauna. The biodiversity of benthic organisms is possibly further enhanced by the geographic position of the region that extends far south into subantarctic waters. However, we currently lack an exhaustive picture of the zonation and ecological functioning of the benthic communities within Chilean fjords. The present study provides a detailed examination of the hard substrata megabenthic communities inhabiting the Puyuhuapi and Jacaf fjord system, in the Aysén Region of Chile. Fifty-nine stations scattered along these fjords were explored through SCUBA diving surveys, at depths between 5 and 30 m, and 16 stations were characterized in terms of benthic cover and diversity using replicated underwater photography. Ten hard bottom megabenthic communities were identified within the fjords, with some communities newly described for this region. Community composition varied both along-fjord, and with depth, and was apparently driven by variation in environmental properties. Our characterization of these fjord communities improves overall knowledge of the functioning of the fjords, and provides a useful baseline against which future anthropogenic pressures can be assessed. Future shifts in bathymetric and geographical distributions might indicate detrimental effects of climate changes, and we therefore propose that characteristic communities could be adopted as “sentinels” for overall environmental status of these unique fjord ecosystems. In this regard, detailed mapping of the distribution of megabenthic communities can provide a fundamental tool that assists in best management practices for these ecosystems.

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Distribution and abundance of benthic macroorganisms in and around Visakhapatnam Harbour on the east coast of India

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315414001490 ◽

2014 ◽

Vol 95 (2) ◽

pp. 215-231 ◽

Cited By ~ 4

Author(s):

Amar S. Musale ◽

Dattesh V. Desai ◽

S. S. Sawant ◽

K. Venkat ◽

A. C. Anil

Keyword(s):

Species Diversity ◽

Organic Carbon ◽

Dissolved Oxygen ◽

East Coast ◽

Benthic Communities ◽

Sediment Characteristics ◽

Polychaete Species ◽

East Coast Of India ◽

Marine Food Chain ◽

Port Area

Benthic communities form an important component of the marine food chain. Their occurrence also provides information on the health of the ecosystem. A study was carried out to understand the distribution and abundance of macrobenthos along with sediment characteristics and physicochemical parameters in Visakhapatnam Harbour, a major port along the east coast of India. In all 84 macrobenthic taxa were reported from the port area of which 60 were polychaetes and 24 were other invertebrate taxa. Our observations revealed an increase in the number of polychaete species observed over the last 20 years from this region. An earlier study reported 38 polychaete species in 1975 and a year later the number of polychaete species reported was 12, indicating an increase in the number of polychaete species in the present study by about 150%. The macrobenthic abundance and dominance of species varied with the seasons. Pre-monsoon was dominated by Cirratulus sp., during monsoon tanaids were dominant indicating a seasonal shift in the occurrence and dominance of macrobenthos. During post-monsoon, Cossura coasta was dominant followed by Nephtys dibranchis and amphipods. Sediment characteristics (sand, silt and clay), organic carbon and dissolved oxygen were the important factors influencing the abundance and species diversity. The abundance of macrobenthic forms also varied with inner and outer harbour region. Higher species diversity was observed in the outer harbour suggesting the outer harbour has semi-polluted conditions such as higher dissolved oxygen (DO) and salinity, low nutrients (nitrite, nitrate and silicate) and low organic carbon in the sediment.

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