Journal articles: 'Benthic invertebrate community'

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Wong, Allan HK, Donald J. McQueen, D. Dudley Williams, and Eric Demers. "Transfer of mercury from benthic invertebrates to fishes in lakes with contrasting fish community structures." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 6 (June 1, 1997): 1320–30. http://dx.doi.org/10.1139/f97-035.

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We examined the flow of mercury (Hg) from benthic invertebrates to fishes in lakes with contrasting fish community structure. The study was carried out in two whole lakes in southcentral Ontario in 1992. Both were remote from direct sources of contamination and were chosen because of their physical and chemical similarities. Although the fish communities in the two lakes were qualitatively similar, the total number of fishes in Ranger Lake was an order of magnitude smaller than that in Mouse Lake. As a result of the lower net predation from benthivorous fishes, documented in earlier studies, Ranger Lake benthic invertebrate populations were significantly higher. However, benthic invertebrate taxa in Mouse Lake were generally larger and had higher Hg concentrations. This was partly attributed to the stunted growth of Mouse Lake fishes, which did not allow them to prey on larger benthos as a result of gape limitations. Despite the lower Hg concentrations in Ranger Lake benthos, total benthic invertebrate Hg pools were higher in this lake as a result of its higher total benthic invertebrate biomass. However, the transfer of total Hg from benthic invertebrates to fishes was higher in Mouse Lake due to the higher consumption rates of benthivorous fishes.

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Jackson, Donald A., and Harold H. Harvey. "Fish and Benthic Invertebrates: Community Concordance and Community–Environment Relationships." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 12 (December 1, 1993): 2641–51. http://dx.doi.org/10.1139/f93-287.

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Fish and benthic invertebrates from 40 lakes in south-central Ontario showed significantly concordant patterns based on community structure. Fish communities were associated significantly with lake morphological characteristics, but were uncorrelated with water chemistry. Large, deep lakes differed from shallow lakes in their fish species, having richer faunas due to the additional cold-water species. Centrarchid species occurred more frequently in small, shallow lakes than in larger lakes. The invertebrate community was not correlated with lake morphology, but showed a significant association with water chemistry, principally lake pH. A strong contrast in the abundance of Chaoborus and Holopedium existed, but it was unclear whether this was due to a predator–prey relationship or to differences in acid tolerance. Although the lakes showed similar patterns in the composition of both communities, each community was associated with a different set of environmental factors. Biotic processes within and between communities explain this paradox in community–environment relationships. Such biotic interactions may involve direct processes such as fish predation on a particular invertebrate taxon or indirect factors, e.g., where fish limit the abundance of invertebrate predators, thereby limiting the impact of these invertebrate predators.

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Al-Ameen, Feryal A. M. "An Ecological Survey of Benthic Invertebrates in Three Sites in Shatt-Al-Kufa at Al-Najaf Province, Iraq." JOURNAL OF UNIVERSITY OF BABYLON for Pure and Applied Sciences 26, no. 8 (October 15, 2018): 230–39. http://dx.doi.org/10.29196/jubpas.v26i8.1691.

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The present study was conducted to determine the structure of benthic invertebrates community, as well as a study of some factors associated with water quality in Shatt Al-Kufa. The study was included a choice of three sites located along the Shatt Al-Kufa River, water samples and benthic invertebrates were collected during the period from February 2014 to January 2015. The abiotic study included measurements of chlorophyll a, salinity, total dissolved solids, biochemical oxygen demand, total hardness, nitrate, and sulfate. The biotic study included the determination the composition of the benthic invertebrates community through the study of the mean population density, the relative abundance index of these organisms and the Jaccard Coefficient was calculated to identify the value of similarity between the studied sites. In the present study, 28 taxa of benthic invertebrates were recorded belong to 4 main groups which are: 8 taxa belonged to Annelida, 7 belonged to Insecta, 10 belonged to Mollusca, 3 belonged to Nematoda. Annelida recorded the highest percentage 40.8% of the total number of benthic invertebrates, Insecta with 30.3%, Mollusca and Nematoda with 28.4 %, 0.5% respectively. Benthic invertebrate has shown positive and negative relationships with the studied physical and chemical characteristics.

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Bond, M. J., D. Rowan, R. Silke, and J. Carr. "Drivers of Abundance and Community Composition of Benthic Macroinvertebrates in Ottawa River Sediment near Chalk River Laboratories." AECL Nuclear Review 2, no. 2 (December 1, 2013): 41–54. http://dx.doi.org/10.12943/anr.2013.00017.

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The Ottawa River has received effluent from Chalk River Laboratories (CRL) for more than 60 years. Some radionuclides and contaminants released in effluents are bound rapidly to particles and deposited in bottom sediments where they may be biologically available to benthic invertebrates and other aquatic biota. As part of a larger ecological assessment, we assess the potential impact of contaminated sediments in the vicinity of CRL on local benthic community structure. Using bivariate and multivariate approaches, we demonstrate that CRL operations have had little impact on the local benthic community. Despite elevated anthropogenic radionuclide activity concentrations in sediment near CRL’s process outfall, the benthic community is no less abundant or diverse than what is observed upstream at background levels. The Ottawa River benthic invertebrate community is structured predominantly by natural physical and biological conditions in the sediment, specifically sediment water content and organic content. These natural habitat conditions have a stronger influence on macroinvertebrate communities than sediment contamination.

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Michiels, Iris C., and Walter Traunspurger. "Benthic community patterns and the composition of feeding types and reproductive modes in freshwater nematodes." Nematology 7, no. 1 (2005): 21–36. http://dx.doi.org/10.1163/1568541054192234.

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Abstract We characterised benthic invertebrate community composition in 11 oligotrophic, alpine lakes. Nematodes were the most abundant benthic taxa in most lakes but community composition differed markedly. Several relationships between the invertebrate taxa were found but there was no strong evidence that competition or predation shaped the benthic community structure. Most lakes were dominated by a few nematode species with cosmopolitan distribution. Obligate and/or facultative parthenogenetic species were most abundant. With increasing species richness, the overall sex-ratio increased and the relative abundance of parthenogenetic species decreased.

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Umar, D. M., J. S. Harding, and H. M. Chapman. "Response of benthic invertebrate communities to a land use gradient in tropical highland streams in Nigeria." Tropical Freshwater Biology 26, no. 1 (March 15, 2018): 53–76. http://dx.doi.org/10.4314/tfb.v26i1.5.

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Benthic invertebrate communities have been shown to respond to habitat degradation as a result of land use changes. Although these changes have been well documented in temperate regions, their effects in the tropics have been poorly documented particularly where land use activities differ markedly (e.g., tea, maize and plantations). A survey 55 1st and 2nd order highland tropical streams, across four land use categories, ranging from continuous tropical montane rain forest to intensive crops and pasture. Streams were sampled in the tropical dry season (October–March) for physico-chemical parameters and components of the biological community, (i.e., fine particulate organic matter [FPOM], coarse particulate organic matter [CPOM], algae and benthic invertebrates). Catchment riparian conditions and human water use activities were used to generate a multivariate land use intensity gradient score. Temperatures in pasture streams were warmer than forest streams (up to 25oC) and dissolved oxygen levels frequently low (15–79%). However, physico-chemical conditions did not show any clear patterns across land uses categories. In contrast, benthic invertebrate communities showed strong response with the highest taxonomic diversity in continuous forest streams (mean 20 taxa) and the lowest in streams with intensive crops (e.g., cabbage crops, mean 8 taxa). Marked changes were found in invertebrate communities with several taxa occurring primarily in forested streams (e.g., the mayflies Heptageniidae and Oligoneuriidae and brachyuran crabs). Tropical land use farming (e.g., tea, maize, cabbage) have significant impacts on the benthic invertebrate assemblages of highland streams in Nigeria. However, not all crop and plantation streams had highly impacted communities because some have wider riparian buffer zones. This study further highlight the importance of conservation and management of montane forest fragments in these regionsKeywords: Tropical, Nigeria, highland, benthic invertebrates, land use, degradation

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Têtu, Catherine, Sean Mitchell, Charles MacInnis, and Barry R. Taylor. "Restoration of a Nova Scotia stream to enhance Atlantic salmon provides few benefits to benthic invertebrates." Proceedings of the Nova Scotian Institute of Science (NSIS) 48, no. 2 (May 7, 2016): 211. http://dx.doi.org/10.15273/pnsis.v48i2.6656.

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Stream restoration is often undertaken with the goal of improving habitat for one focal species, most often a salmonid fish such as trout or salmon. Improvements in channel structure, especially the flushing of silt from sediments, should also benefit benthic invertebrate communities, but studies to date suggest substantial changes in benthic communities following restoration are not common. In a third-order Nova Scotia stream, we examined the effect of successful restoration to improve habitat for spawning Atlantic salmon on benthic invertebrate communities at sites where clogging of the bottom cobble with fine silt had been alleviated. In a long-term comparison of two restored sites and two degraded sites, only six of 24 insect taxa showed increased population density five or seven years after restoration. In a second comparison of a comparatively undisturbed site against a newly restored site and a site restored eight years earlier, only three invertebrate taxa appeared to respond positively and consistently to restoration. In both studies there were no substantial changes in total invertebrate density, taxa richness, Simpson’s diversity index or other community metrics over five years, except for a decline in the EPT/Chironomids ratio in the second study. Ordination of sites by correspondence analysis showed that, in both studies, benthic communities at unrestored control sites and restored sites were clearly different and did not become more similar through time. A long-term restructuring of the benthic community in the entire brook is suggested by the appearance of silt-intolerant shredders (Lepidostoma, Leuctra) among the most abundant members of the benthos in the second study, replacing silt-tolerant collectors (Tricorythodes, Optioservus) that dominated the earlier study. Habitat factors unaffected by in-stream restoration (frequent high discharge, lack of woody debris) limit benthic communities more than substratum quality.

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Basu, Arnab, Indrani Sarkar, Siddartha Datta, and Sheela Roy. "Community structure of benthic macroinvertebrate fauna of river Ichamati, India." Journal of Threatened Taxa 10, no. 8 (July 26, 2018): 12044. http://dx.doi.org/10.11609/jott.3439.10.8.12044-12055.

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Benthic macroinvertebrate communities are frequently applied as indicators of aquatic ecosystem health as many species are responsive to pollution and abrupt changes in their surroundings. The qualities of benthic invertebrate communities greatly depend on habitat conditions. Thus the diversity in benthic community varies with different habitat conditions. This investigation on the structure of the benthic invertebrate communities was conducted on river Ichamati, a trans-boundary river between India and Bangladesh to assess the cumulative effects of water quality on the aquatic biota. The study period extended from February 2011 to January 2014 at three sites from Majdiah to Hasanabad (in West Bengal, India) a stretch of 124km. A total of 23 macrobenthic species belonging to three phyla, five classes and nine orders were identified. Fifteen species of benthic invertebrates belonging to Mollusca, three species under Annelida and five species under Arthropoda were found. The highest abundance density (3633.33 indiv.m-2) and species richness (18 species) were recorded up-stream (Majdiah) where marginal habitats covered by macrophytes were significantly higher than at other sites. Both the organic carbon (4.41±1.11) and organic matter (7.48±1.56) of soil at this site were the maximum thus influencing the richness of benthic macroinvertebrate communities. Hydrological variables, viz, dissolved oxygen, pH, alkalinity; hardness, salinity, nutrients, calcium, and magnesium were studied to determine their influences on the benthic community in the upper, middle- and down-streams of the river, respectively. Shannon’s diversity index (0.95–2.07; 0.00–0.72; 0.00–0.64), dominance index (0.57–0.86; 0.00–0.44; 0.00–0.44), evenness index (0.72–0.95; 0.61–1.00; 0.00–1.00), Margalef index (0.72–2.23; 0.00–1.32; 0.00-0.28) of the upper, middle- and down-streams were calculated. Benthic macroinvertebrate density was correlated with hydrological variables which indicated that the abiotic factors had either direct or inverse influence on the richness and abundance; however, the abiotic factors did not correlate identically in all three sites.

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Metzeling, L. "Benthic macroinvertebrate community structure in streams of different salinities." Marine and Freshwater Research 44, no. 2 (1993): 335. http://dx.doi.org/10.1071/mf9930335.

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The likely effect of salinization on stream invertebrates was studied by comparing macroinvertebrate community structure at nine sites in six lowland, perennially flowing streams. The salinity of these streams ranged from 51 to 1100 mg L-1 total dissolved solids (TDS) (and were historically higher, up to about 2000 mg L-1 TDS). There was no correlation between either number of taxa or faunal abundance with salinity. However, multivariate analyses showed distinct invertebrate communities associated with different salinities. Fidelity analysis identified groups of taxa associated with either low or high salinity. Existing information on the distribution of the common taxa within these groups indicated that they were tolerant of wider ranges in salinity than those found in this study. The rare taxa most clearly distinguished between sites of different salinities and are possibly more sensitive to changes in salinity.

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Parker, Roy, and Charles Dumaresq. "Effluent Characterization, Water Quality Monitoring and Sediment Monitoring in the Metal Mining EEM Program." Water Quality Research Journal 37, no. 1 (February 1, 2002): 219–28. http://dx.doi.org/10.2166/wqrj.2002.014.

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Abstract The metal mining Environmental Effects Monitoring (EEM) program will require mines to conduct effluent characterization and water quality monitoring on an ongoing basis. Samples will be collected four times a year, and will be analyzed for a range of parameters. This information will be used to aid in the design and interpretation of fish surveys and benthic invertebrate community surveys. There are also a number of water quality monitoring methods that may be used to help determine the cause of any effects identified by the EEM program. Mines will also be required to collect sediment samples for determination of particle size distribution and total organic carbon. This information will be used in the design and interpretation of benthic invertebrate community surveys. A range of sediment monitoring techniques are available to aid in the determination of the causes of effects on the benthic invertebrate community.

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Grapentine, Lee, Quintin Rochfort, and Jiri Marsalek. "Benthic Responses to Wet-Weather Discharges in Urban Streams in Southern Ontario." Water Quality Research Journal 39, no. 4 (November 1, 2004): 374–91. http://dx.doi.org/10.2166/wqrj.2004.050.

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Abstract Urban stormwater and combined sewer overflow (CSO) discharges are important sources of sediment and contaminants (trace metals, PAHs, nutrients and road salts), and cause changes in flow, sediment, chemical and thermal regimes of receiving waters. Over the past several years, benthic conditions of streams representing a range of exposure environments were assessed in Hamilton, Toronto, Oshawa and Kingston, Ontario. Studies progressed from initial surveys of sediment contaminant levels, sediment toxicity and benthic invertebrate community structure to more spatially intensive sampling and experimental approaches that included the use of artificial substrates, in situ water toxicity tests and measurements of contaminant bioaccumulation. Results showed that while sediments and some biota at sites exposed to wet-weather discharges were often contaminated with metals and PAHs and enriched with nutrients, significant biological degradation measured by sediment toxicity or depauperated benthic communities was not evident. Exposure to stormwater discharges at sites below outfalls could alter the composition of benthic communities, but these effects were not strongly related to contaminant concentrations in sediment or invertebrate tissue. No outfall-associated toxicity was observed for caged amphipods held in the water column. Effects of wet-weather discharges on benthic communities at the urban stream sites studied appear to be small, and their detection was limited by several inherent conditions, including natural heterogeneity in the distribution of benthic invertebrates, episodic (intermittent) exposure to discharges and contaminant fluxes allowing some recovery, “background” levels of disturbance, poorly delineated changes in communities caused by physical effects such as flow and sediment transport, and community response dynamics. Detection of stormwater discharge effects should be improved by sampling on smaller temporal and multiple spatial scales to better quantify stressor exposure and invertebrate responses.

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Negus, Peter M., Jonathan C. Marshall, Alisha L. Steward, Glenn B. Mcgregor, and Ruth A. O'Connor. "Aquatic biota in hot water: thermal gradients in rheocrene hot spring discharges as analogues for the effects of climate warming." Knowledge & Management of Aquatic Ecosystems, no. 421 (2020): 49. http://dx.doi.org/10.1051/kmae/2020042.

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Hot springs are characterised by water temperatures above 36.7 °C. Temperature decreases with distance in flow away from spring vents; this natural gradient provides a unique opportunity to investigate the influence of water temperature on aquatic biota. This study investigated the relationship between water temperature and the aquatic invertebrates and benthic diatoms in outflows from a hot spring complex in tropical north Queensland, Australia. Water temperature ranged from 62.7 °C at the vents to 26.0 °C at the location furthest downstream. Richness of benthic diatoms and aquatic invertebrates increased linearly in response to decreasing temperature, with no species present in the hot vents. Multivariate analysis showed that both community assemblages had a response to the temperature gradient. A drop in aquatic invertebrate richness and a change in assemblage composition occurred between 40 °C and 42 °C, indicating a threshold at this temperature. The nearby Einasleigh River has experienced several contemporary peaks in water temperature over 40 °C, which corresponds to this threshold level. The relationships indicate that consistent increases in water temperature expected under climate change could decrease biological richness and precipitate changes in the aquatic invertebrate and benthic diatom taxa of tropical aquatic ecosystems.

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Lingdell, P. E., and E. Engblom. "Liming restores the benthic invertebrate community to ?pristine? state." Water, Air, & Soil Pollution 85, no. 2 (1995): 955–60. http://dx.doi.org/10.1007/bf00476953.

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Delucchi, Carla M. "Comparison of community structure among streams with different temporal flow regimes." Canadian Journal of Zoology 66, no. 3 (March 1, 1988): 579–86. http://dx.doi.org/10.1139/z88-085.

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A study was conducted in four streams in the same watershed in New York to determine whether the benthic invertebrate community structure varied among streams with different temporal flow regimes. Timed kick samples were taken from 13 riffles and 4 pools once a month from June to November 1982. Riffle sites were classified according to temporal flow regime as permanent, intermittent (dry for less than 3 months), or dry (dry for over 3 months), and varied in size as a function of discharge. Ordination analysis (detrended correspondence analysis) showed that the structure of the benthic invertebrate communities in these streams was related not only to riffle permanence, but also to other abiotic and biotic parameters. Differences in community structure were greater between adjacent pools and riffles than between temporary and permanent riffles. Stream size, seasonal changes in taxa, how recently the riffle had dried, and the length of the dry period contributed to differences in community structure among riffles. It appears that differences in community structure between permanent and temporary riffles are minimized by generalized adaptations of stream benthos, such as high rates of migration, drought-resistant eggs, and the tendency to take refuge in the hyporheic zone.

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Zerlin, RA, and R. Henry. "Does water level affect benthic macro-invertebrates of a marginal lake in a tropical river-reservoir transition zone?" Brazilian Journal of Biology 74, no. 2 (May 2014): 408–19. http://dx.doi.org/10.1590/1519-6984.26812.

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Benthic macro-invertebrates are important components of freshwater ecosystems which are involved in ecological processes such as energy transfer between detritus and consumers and organic matter recycling. The aim of this work was to investigate the variation in organism richness, diversity and density of benthic fauna during the annual cycle in Camargo Lake, a lake marginal to Paranapanema River, southeast Brazil. The correlation of environmental factors with community attributes of the macro-benthic fauna was assessed. Since Camargo Lake is connected to the river, we tested the hypothesis that water level variation is the main regulating factor of environmental variables and of the composition and abundance of benthic macro-invertebrates. The results indicated that lake depth varied with rainfall, being the highest at the end of the rising water period and the lowest at the beginning of this period. The sediment granulometry was more heterogeneous at the bottom of the lake by the end of the high water period. The benthic macro-invertebrate fauna was composed by 15 taxa. The Diptera order was represented by seven taxa and had greater richness in relation to other taxa. This group was responsible for 60% of the total abundance of organisms, followed by Ephemeroptera (22%) and Anellida (16%). Significant differences were observed over time in total richness and, in density of Narapa bonettoi, Chaoborus, Ablabesmyia gr. annulata, Chironomus gigas, Larsia fittkau, and Procladius sp. 2. Total taxa richness correlated negatively with water pH, transparency, conductivity, and bottom water oxygen. Higher positive correlations were found between the densities of some taxa and bottom water oxygen, conductivity and very fine sand, silt + clay of sediment, while negative correlations were recorded with organic matter, and fine, medium and coarse sand, bottom water temperature, mean temperature and rainfall. The significant temporal difference in water level was associated with changes in abiotic factors and macro-invertebrate community attributes.

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Rosenfeld, Jordan. "Effects of fish predation in erosional and depositional habitats in a temperate stream." Canadian Journal of Fisheries and Aquatic Sciences 57, no. 7 (July 1, 2000): 1369–79. http://dx.doi.org/10.1139/f00-073.

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Combined effects of predation by benthic and drift-foraging fish (prickly sculpin (Cottus asper) and coho salmon (Onchorhynchus kisutch) parr) on benthic invertebrate community and trophic structure were evaluated in Mayfly Creek, a previously fishless stream in the Coast Range Mountains of British Columbia. The role of microhabitat (substrate) in mediating predation effects was assessed by comparing invertebrate community structure on unglazed ceramic tiles and gravel baskets nested within enclosures. The role of macrohabitat was evaluated by placing enclosures in pool and riffle habitats. Effects of fish predation were most pronounced on tile substrate and in riffle habitat and least pronounced on gravel substrate in pool habitat. The presence of fish caused a decrease in abundance of larger-bodied herbivores (primarily the mayflies Ameletus and Baetis) and had positive indirect effects on algae and smaller invertebrates (primarily Orthocladiinae chironomids and nemourid stoneflies), probably through competitive release. In contrast with herbivores, detritivorous invertebrates were less influenced by fish predation and more highly correlated with the abundance of organic detritus. The distribution and abundance of detritivores in Mayfly Creek appear to be primarily influenced by bottom-up forces (implying resource limitation), while grazers in algal-based food chains are more strongly influenced by top-down effects (fish predation).

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Lo Giudice, Angelina, and Carmen Rizzo. "Bacteria Associated with Marine Benthic Invertebrates from Polar Environments: Unexplored Frontiers for Biodiscovery?" Diversity 10, no. 3 (August 2, 2018): 80. http://dx.doi.org/10.3390/d10030080.

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The ecological function of bacteria-invertebrate interactions in Polar areas remains poorly understood, despite increasing evidence that microbial metabolites may play pivotal roles in host-associated chemical defense and in shaping the symbiotic community structure. The metabolic and physiological changes that these organisms undergo in response to adapting to extreme conditions result in the production of structurally and functionally novel biologically active molecules. Deepening our knowledge on the interactions between bacteria and their invertebrate host would be highly helpful in providing the rationale for why (e.g., competition or cooperative purpose) and which (whether secondary metabolites, enzymes, or proteins) bioactive compounds are produced. To date, cold-adapted bacteria associated with marine invertebrates from the Arctic and Antarctica have not been given the attention they deserve and the versatility of their natural products remains virtually unexplored, even if they could represent a new attractive frontier in the search for novel natural compounds. This review is aimed at showcasing the diversity of cold-adapted bacteria associated with benthic invertebrates from Polar marine areas, highlighting the yet unexplored treasure they represent for biodiscovery.

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Young, Robert J., and Gerald L. Mackie. "Effect of oil pipeline construction on the benthic invertebrate community structure of Hodgson Creek, Northwest Territories." Canadian Journal of Zoology 69, no. 8 (August 1, 1991): 2154–60. http://dx.doi.org/10.1139/z91-301.

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During the ice-free seasons of 1984 and the winter and summer of 1985, we determined the effect of winter oil pipeline construction on benthic invertebrates of Hodgson Creek, Northwest Territories. Total suspended sediments increased from < 2 mgL−1 to > 300 mg L−1 at sampling stations downstream of the pipeline right-of-way during construction, with peak concentrations exceeding 3000 mg L−1. A concurrent increase in benthic invertebrate drift density from 2.6 to 37.6/100 m−3 was observed downstream of construction. The effects of pipeline installation were observed up to 5 weeks following the end of construction. Following the spring snowmelt in 1985, no significant difference in standing crop, species richness, or functional group composition between stations upstream and downstream of the pipeline right-of-way was observed. We concluded that the negative impact of pipeline construction was limited to the period between construction and spring ice breakup. The frequency and magnitude of spate events were sufficient to remove accumulated sediment. Thus, the impact of natural perturbations in Hodgson Creek was greater than the effect of pipeline construction on benthic community structure.

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Ali, Luay, and Hayfa Jiwar. "Community Structure of Benthic invertebrate in Greater Zab River/Iraq." JOURNAL OF EDUCATION AND SCIENCE 20, no. 2 (October 1, 2007): 38–46. http://dx.doi.org/10.33899/edusj.2007.162796.

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Przeslawski, Rachel, David R. Currie, Shirley J. Sorokin, Tim M. Ward, Franziska Althaus, and Alan Williams. "Utility of a spatial habitat classification system as a surrogate of marine benthic community structure for the Australian margin." ICES Journal of Marine Science 68, no. 9 (July 13, 2011): 1954–62. http://dx.doi.org/10.1093/icesjms/fsr106.

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Abstract Przeslawski, R., Currie, D. R., Sorokin, S. J., Ward. T. M., Althaus, F., and Williams, A. 2011. Utility of a spatial habitat classification system as a surrogate of marine benthic community structure for the Australian margin. – ICES Journal of Marine Science, 68: 1954–1962. This study tests whether a continental-scale classification of Australian benthic habitats (termed “seascapes”) and the interpolated environmental data from which they are derived are useful as abiotic surrogates of biodiversity at a local [tens of kilometres, Great Australian Bight (GAB)] and regional scale [hundreds of kilometres, Western Australian (WA) margin]. Benthic invertebrate community structure is moderately associated with specific seascapes in both the GAB (R = 0.418) and WA margin (excluding hard substrata, R = 0.375; all substrata, R = 0.313). Mud content, seafloor slope, and seafloor temperature are significantly correlated with invertebrate communities at both scales, with disturbance and primary production correlated with GAB communities. Seascapes are not consistently useful surrogates because the strength and significance of relationships between seascapes and community structure differs among seascapes, regions, and spatial scales. Nevertheless, a national system of seascapes is an appropriate surrogate for broad-scale benthic invertebrate community patterns when biological data are limited, provided the uncertainty is acknowledged and, where possible, an assessment made of each seascape's ability to differentiate biological communities. Further refinement of seascape derivations may include updated and additional environmental data (particularly for hard vs. soft substrata) and validation among biological datasets from a range of habitats and scales.

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Collie, Jeremy S., Anthony D. Wood, and H. Perry Jeffries. "Long-term shifts in the species composition of a coastal fish community." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 7 (July 2008): 1352–65. http://dx.doi.org/10.1139/f08-048.

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To study decadal shifts in a coastal nekton community, we analyzed data on 25 fish and invertebrate species collected from 1959 to 2005 by the University of Rhode Island, Graduate School of Oceanography (Narragansett, Rhode Island, USA). This weekly trawl survey samples two locations: inside Narragansett Bay and in Rhode Island Sound. Over four decades, the community has shifted progressively from vertebrates to invertebrates and, especially since 1980, from benthic to pelagic species. Demersal species that declined include winter flounder ( Pseudopleuronectes americanus ), silver hake ( Merluccius bilinearis ), and red hake ( Urophycis chuss ); meanwhile warm-water fish (butterfish, Peprilus triacanthus ; scup, Stenotomus chrysops ) and invertebrates (lobster, crab, squid) increased with time. Total numbers reached a maximum in the 1990s, while mean body size decreased. Taxonomic diversity increased over time, as the community shifted from fish to invertebrates of several phyla. The shifts in species composition correlate most strongly with spring–summer sea surface temperature, which increased 1.6 °C over the 47-year time series. Species composition was also correlated with the winter North Atlantic Oscillation index and chlorophyll concentration, which has declined since the 1970s. Triggered primarily by rising temperatures, these decadal changes have altered the trophic structure of the nekton community, resulting in a shift from benthic to pelagic consumers.

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Siler, Edward R., J. Bruce Wallace, and S. L. Eggert. "Long-term effects of resource limitation on stream invertebrate drift." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 8 (August 1, 2001): 1624–37. http://dx.doi.org/10.1139/f01-101.

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We examined the effects of resource limitation on stream invertebrate drift by reducing inputs of terrestrial detritus to a headwater stream in western North Carolina. In the treatment stream, leaf-litter was excluded for 6 years (September 1993 August 1999), small woody debris was removed for 2 years (September 1996 August 1998), and large and small woody debris was removed for 1 year (September 1998 August 1999). Invertebrate abundance in the drift was significantly lower in the treatment stream during the study, but total biomass of invertebrate drift was similar. Although drift densities were higher in the reference stream, a greater proportion of total benthic invertebrate abundance and biomass drifted out of the treatment stream. The proportion of shredder, gatherer, and predator benthic abundance in the drift was significantly greater in the treatment stream, but scraper proportions were higher in the reference stream and filterer proportions were similar for the two streams. Combined data from both streams indicated that the relationship between drift densities and benthic abundance was positive and significant. Our results demonstrate that bottom-up effects of resource reduction in a detrital-based stream influence invertebrate drift, increasing the proportion of the benthic community emigrating from the detritus-poor stream.

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Robertson, Anne, Daniel Perkins, Judy England, and Tim Johns. "Invertebrate Responses to Restoration across Benthic and Hyporheic Stream Compartments." Water 13, no. 7 (April 4, 2021): 996. http://dx.doi.org/10.3390/w13070996.

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River restoration is a multi-billion-dollar business, yet it is unclear whether benthic community health, which is routinely monitored, can be used as a proxy for the health of the hyporheos. Applying a Before-After-Control-Impact approach to a UK case study, we compared the effects of removing an impoundment on the hyporheos with effects on the benthos. We compared invertebrate biological traits that we expected to respond to the restoration. We constructed sample-size based diversity curves and determined β-diversity between compartments and reaches. Two years post-restoration, hyporheic taxon richness was significantly lower in the restored reach compared to the control. However, three years post-restoration taxon richness was significantly higher in the impact reach. The composition of the control and impact reach hyporheos was most dissimilar at the first sampling time point post-restoration and at this time there was a universal decrease in the relative abundance of burrowing organisms respiring through gills. We did not detect a signal of restoration on benthic assemblage diversity and composition, perhaps because reach-scale restorations can be overwhelmed by catchment-scale disturbances. Thus, the hyporheos and the benthos responded differently to restoration. Given the importance of the hyporheic zone in the provision of ecosystem function and services, it is clear that it should be included in future monitoring protocols that aim to assess river restoration success.

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Baillie, Brenda R., Brendan J. Hicks, Ian D. Hogg, Michael R. van den Heuvel, and Mark O. Kimberley. "Debris dams as habitat for aquatic invertebrates in forested headwater streams: a large-scale field experiment." Marine and Freshwater Research 70, no. 5 (2019): 734. http://dx.doi.org/10.1071/mf18216.

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To evaluate the effects of debris dams on aquatic invertebrate communities, we sampled benthic invertebrates in debris dams and riffles in three forested headwater streams in New Zealand. As part of a large-scale field experiment, debris dams were subsequently removed from three treatment sections in each of the streams to assess effects on invertebrate communities. Prior to debris dam removal, total invertebrate densities in debris dams were not significantly different from those in riffles. However, densities of Ephemeroptera, Plecoptera and Trichoptera taxa were significantly higher in debris dams than in riffles. Debris dams contained a higher number of less common taxa (defined as <1% of total catch) and significantly higher densities of shredders. Densities for Coleoptera, Diptera and Trichoptera taxa were significantly higher in the autumn than in the spring. Non-metric multidimensional scaling axis scores indicated that both habitat and season had a significant effect on aquatic invertebrate community composition. At the reach scale, the effects of debris dam removal on the aquatic invertebrate communities were not statistically detectable because debris dams comprised only a small proportion of total habitat. However, these data highlight the importance of debris dams in contributing to the diversity of aquatic invertebrates in forested headwater streams.

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Dangles, Olivier. "Functional plasticity of benthic macroinvertebrates: implications for trophic dynamics in acid streams." Canadian Journal of Fisheries and Aquatic Sciences 59, no. 9 (September 1, 2002): 1563–73. http://dx.doi.org/10.1139/f02-122.

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Functional plasticity of benthic macroinvertebrates was investigated over one year in four acid streams in the Vosges Mountains (northeastern France). The trophic position of macroinvertebrate species within the benthic food web was determined using gut content analyses. Diet analyses revealed that only 2436% of biomass of putative shredders consumed leaf fragments, whereas up to 44% consumed benthic algae and bryophytes. Although most Nemouromorpha stoneflies were generalist consumers, several other taxa (e.g., Brachyptera seticornis, Chaetopterygopsis maclachlani) specialised on benthic algae and bryophytes. Our study showed that acid streams unexpectedly had very few specialised leaf-shredding species (e.g., Chaetopteryx villosa) that could explain the slow leaf detritus processing rates observed in these systems. Primary producers appear to be an alternative resource for shredders, playing an important role in supporting food webs in forested acid streams. The food web built in this study suggests that overlooking species-specific functional plasticity of invertebrates may result in a misconception of invertebrate community structure in acid streams.

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Emoyoma, Udi O., Aroloye O. Numbere, and Godfrey N. Woke. "Impact of Nypa Palm (Nypa fruticans Wurmb) and Mangroves Forest on Benthic Macro Invertebrate Community in Andoni River, Nigeria." International Letters of Natural Sciences 77 (January 2020): 51–62. http://dx.doi.org/10.18052/www.scipress.com/ilns.77.51.

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It is postulated that the presence of nypa palm (Nypa palm) in mangrove forest affect the reproductive function of fish by inhibiting the growth of macro invertebrates. The impact of Nypa fruticans (Wurmb) and mangroves on the benthic macro invertebrate community of Andoni River was carried out between January and August, 2017. A total of four stations were chosen based on nypa palm and native mangrove species’ presence and absence, station 1 (Open water), Station 2 (Nypa palm dominance), station 3 (Rhizophora and Avicennia dominance), Station 4 (Mixed). Results of water quality parameters include; pH 6.99±0.16, Temperature 28.20±0.05°C, DO 4.71±0.18mg/L, Conductivity 19.52±0.20µm/s, Salinity 10.76±0.07ppt, TDS 13.45±0.27ppt. Mean values of the physico-chemical parameters (P > 0.05) were not significantly different. Twelve taxa of benthic macro-invertebrates in eleven families were collected. The crustaceans were more in diversity (38.46%), while bivalvia, pisces and oligochaete had the least percentage composition (7.69%). The gastropods were more in species dominance (44.69%), while the Oligochaeta were least in abundance (0.61%). Shannon Weiner’s index across the stations for benthos was highest in station 2 (1.840) and lowest in station 1 (1.103). Simpson’s index was highest in station 2 (1.990) and lowest in station 1 (1.938). Pielou’s index of evenness was highest in station 2 (0.767) and lowest in station 1 (0.616). All the macro-invertebrates recorded were clean water and pollution tolerant species, and showed no significant difference across stations (P>0.05). In conclusion this study indicates that nypa palm does not affect the proliferation of macro invertebrates, which supports fishery population along the food chain.

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Vitecek, Simon, Richard Johnson, and Sandra Poikane. "Assessing the Ecological Status of European Rivers and Lakes Using Benthic Invertebrate Communities: A Practical Catalogue of Metrics and Methods." Water 13, no. 3 (January 30, 2021): 346. http://dx.doi.org/10.3390/w13030346.

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The Water Framework Directive requires that the ecological status of surface waters be monitored and managed if necessary. A central function in ecological status assessment has the Biological Quality Elements—organisms inhabiting surface waters—by indicating human impact on their habitat. For benthic invertebrates, a wide array of national methods are used, but to date no comprehensive summary of metrics and methods is available. In this study, we summarize the benthic invertebrate community metrics used in national systems to assess the ecological status of rivers, (very) large rivers, and lakes. Currently, benthic invertebrate assemblages are used in 26 national assessment systems for rivers, 13 assessment systems for very large rivers, and 21 assessment systems for lakes in the EU. In the majority of systems, the same metrics and modules are used. In the Red Queen’s race of ecosystem management this may be a disadvantage as these same metrics and module likely depict the same stressors but there is growing evidence that aquatic ecosystems are subject to highly differentiated, complex multiple stressor impacts. Method development should be fostered to identify and rank impacts in multi-stressor environments. DNA-based biomonitoring 2.0 offers to detect stressors with greater accuracy—if new tools are calibrated.

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Rochfort, Q., L. Grapentine, J. Marsalek, B. Brownlee, T. Reynoldson, S. Thompson, D. Milani, and C. Logan. "Using Benthic Assessment Techniques To Determine Combined Sewer Overflow and Stormwater Impacts in the Aquatic Ecosystem." Water Quality Research Journal 35, no. 3 (August 1, 2000): 365–98. http://dx.doi.org/10.2166/wqrj.2000.025.

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Abstract Urban wet-weather sources of pollution such as Stormwater and combined sewer overflows (CSOs) can contribute significantly to the contamination of receiving waters, particularly in sediment depositional areas near outfalls. Analyses of sediment chemistry alone are not sufficient to fully assess the effects of these discharges. Toxicity testing and evaluations of benthic invertebrate communities, in conjunction with chemical analyses, provide a more complete characterization. This study assessed relationships among three separate aspects of the benthic environment:sediment chemistry (metals, PAHs and nutrients) and particle size, sediment toxicity (ten endpoints with four benthic taxa), and benthic invertebrate community structure. In this initial survey, ten sites in five different study areas, representing a range of receiving water environments exposed to Stormwater and CSO discharges, were sampled in October 1998. Results of analyses indicated that while contaminant (metals and PAHs) concentrations were relatively high in sediments, biological effects were not evident Toxicity of sediments was low and altered benthic communities were not detected. Neither toxicity endpoints nor benthic community descriptors were related to sediment contaminant levels. To improve the power of these assessments, future investigations of Stormwater and CSO discharge impacts should use “upstream/downstream” sampling designs and study sites with minimal variability of habitat conditions.

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Lafont, M., L. Grapentine, Q. Rochfort, J. Marsalek, G. Tixier, and P. Breil. "Bioassessment of wet-weather pollution impacts on fine sediments in urban waters by benthic indices and the sediment quality triad." Water Science and Technology 56, no. 9 (November 1, 2007): 13–20. http://dx.doi.org/10.2166/wst.2007.737.

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Benthic invertebrate assessments can be used to gauge the impact of urban wet-weather flows in receiving waters. Experiences from Cemagref in France have shown that standardized benthic indices (e.g. Oligochaete Index of Sediment Bioindication - IOBS) can be used to reliably determine the ecological status of urban streams and can be incorporated into the new European Water Framework Directive. The Canadian studies on streams and stormwater ponds using chemical analyses, benthic toxicity testing and benthic invertebrate community structure (i.e. the sediment quality triad) comparisons have shown that toxicity was more likely to occur in ponds at sites with higher concentrations of heavy metals and heavier polycyclic aromatic hydrocarbons, and at greater water depths, where fine sediments from urban runoff accumulated. A more comprehensive evaluation of wet-weather flow impacts could be obtained by combining approaches from both countries.

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Rai, A., D. N. Shah, R. D. T. Shah, and C. Milner. "Influence of environmental parameters on benthic macroinvertebrate assemblages in the headwaters of Bagmati river, Kathmandu valley, Nepal." Banko Janakari 29, no. 1 (August 5, 2019): 53–61. http://dx.doi.org/10.3126/banko.v29i1.25155.

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The distribution of benthic macro invertebrates (BMIs) is affected by various environmental factors. Understanding their response to these factors is a key to assessing freshwater quality. The aim of this research is to understand the influence of different environmental parameters on BMIs assemblages in the headwaters of Bagmati River. The BMIs were sampled following a multi-habitat sampling protocol and the – hydrological and physico-chemical parameters were measured using standard methods. The relationship between environmental parameters and macro invertebrate assemblages was analyzed through Multivariate analysis - Redundancy Analysis and Variation Partitioning. Stream discharge, pH and Dissolved Oxygen were selected for multivariate analysis through backward elimination method. pH and Dissolved Oxygen were important contributing factors explaining the variation in BMIs community. Physico-chemical parameters were found to be the most important group of variables explaining the variation in macro invertebrate assemblages. Only about twenty-five per cent of the variation in the BMIs community was explained by the model so the parameters studied here do not have a high degree of explanatory power.

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Cobb, Susan E., and Mary C. Watzin. "Trophic interactions between yellow perch (Perca flavescens) and their benthic prey in a littoral zone community." Canadian Journal of Fisheries and Aquatic Sciences 55, no. 1 (January 1, 1998): 28–36. http://dx.doi.org/10.1139/f97-205.

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Yellow perch (Perca flavescens) growth rates in northern Lake Champlain have declined in recent years while densities have increased, suggesting resource limitation. At high densities, predators have the potential to influence prey communities, but these effects can be highly complex. Using in situ mesh cages in an unmanipulated littoral zone setting, we examined the effects of two densities (0.5 and 1.5/m2) of yellow perch on (i) their growth and (ii) the abundance of major prey groups in the benthic community. Yellow perch growth rates were significantly lower in the high-density treatment than in the low-density treatment. Because site characteristics were not manipulated, measured covariates reflecting sediment and vegetation variation between cages were used to help clarify treatment effects on benthos. Fish predation on invertebrate prey was significant only in the high-density predator treatment for three of the six prey groups examined (predatory chironomids, prey chironomids, and isopods). For this littoral zone community, availability and abundance of benthic prey strongly influenced yellow perch growth rates; but the effect of yellow perch predation on benthic community structure was only moderate.

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32

Culhane, Fiona E., Robert A. Briers, Paul Tett, and Teresa F. Fernandes. "Response of a marine benthic invertebrate community and biotic indices to organic enrichment from sewage disposal." Journal of the Marine Biological Association of the United Kingdom 99, no. 8 (October 28, 2019): 1721–34. http://dx.doi.org/10.1017/s0025315419000857.

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AbstractNutrient enrichment is a significant cause of ecosystem change in coastal habitats worldwide. This study focuses on the change in a benthic macroinvertebrate community and environmental quality as assessed through different biotic indices following the construction of a sewage outfall pipe in the west of Scotland, from first implementation to seven years after operation of the pipe. Benthic macroinvertebrates are an important part of marine ecosystems because they mediate ecosystem processes and functions, are a key part of food webs and they provide many ecosystem services. Results indicated a clear change in benthic communities over time with an increase in species richness and changes to benthic community composition (specifically feeding type, bioturbation mode and ecological group) towards those indicative of organic enrichment. No clear spatial zonation was observed because organic carbon content increased over the entire area. According to a suite of benthic indices calculated, some negative changes were detectable following the start of sewage disposal, but largely negative community changes, and a change from ‘good’ to ‘moderate’ quality, only occurred seven years after implementation. The increase in species richness in response to increasing disturbance reduced the utility of a multi-metric index, the Infaunal Quality Index, which, instead of amplifying the signal of negative impact, dampened it. We suggest that any change in communities, regardless of direction, should be heeded, and species richness is a particularly sensitive and early warning indicator for this, but a suite of approaches is required to understand benthic community changes.

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Rader, Russell B. "A functional classification of the drift: traits that influence invertebrate availability to salmonids." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 6 (June 1, 1997): 1211–34. http://dx.doi.org/10.1139/f97-025.

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Twelve categories/traits were used to classify and rank aquatic invertebrates based on their propensity to drift and importance as a food resource for salmonids. Invertebrate availability was based on their (i) propensity to intentionally drift, (ii) likelihood of being accidentally dislodged by the current, (iii) drift distance, (iv) adult drift, (v) benthic exposure, (vi) body size, and (vii) abundance. This study represents the first attempt to characterize the intentional drift propensity of stream invertebrates. A ranking procedure separated invertebrates into Baetis and three groups decreasing in availability. Predicted ranks were significantly correlated with the actual rank of invertebrates in trout guts taken in three separate studies conducted in the central Rocky Mountains, suggesting that this procedure can effectively rank invertebrates based on their availability as a food resource for salmonids. A cluster analysis separated the 95 taxa into four drift guilds and six availability groups. This study provides criteria for determining when alterations in invertebrate community composition will affect food resources for higher trophic levels by causing a decline in the most available taxa. This research also supports previous findings that floods are important in maintaining invertebrates that represent an important food resource for salmonids.

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Richardson, John S., and Chris J. Perrin. "Effects of the Bacterial Insecticide Bacillus thuringiensis var. kurstaki (Btk) on a Stream Benthic Community." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 5 (May 1, 1994): 1037–45. http://dx.doi.org/10.1139/f94-103.

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Commercial formulations of the insecticidal bacterium Bacillus thuringiensis var. kurstaki (Btk) are frequently sprayed over bodies of water. The hypothesis that Btk poses a threat to stream communities was tested using streamside, flow-through mesocosms which received water and invertebrate colonists from a second-order stream in southwestern British Columbia; low (50 BIU/ha) and high (≥ 5000 BIU/ha) treatment levels were contrasted with controls. There were no significant differences in the density or composition of benthos sampled 7 d after Btk application. The densities were highest in the high-dose mesocosms. There were no significant differences in emergence rate of adults due to treatment. During the 2.5-h treatment, there were marginally elevated drift rates of the mayfly Baetis when exposed to the solution, but these differences were negated during the remainder of the 24-h period. Leaf packs lost significantly more mass in controls than in high-dose mesocosms, but there were no significant differences in the numbers of macro-invertebrates on those leaf packs. There was no evidence that addition of Btk to stream mesocosms created adverse effects for this benthic community, even at > 100 times expected exposure rates.

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Gilliam, James F., Douglas F. Fraser, and Alberto M. Sabat. "Strong Effects of Foraging Minnows on a Stream Benthic Invertebrate Community." Ecology 70, no. 2 (April 1989): 445–52. http://dx.doi.org/10.2307/1937549.

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Pollard, A. I., and L. Yuan. "Community Response Patterns: Evaluating Benthic Invertebrate Composition In Metal-Polluted Streams." Ecological Applications 16, no. 2 (April 2006): 645–55. http://dx.doi.org/10.1890/1051-0761(2006)016[0645:crpebi]2.0.co;2.

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Oppong, Samuel K., Collins Ayine Nsor, and Gabriel Kwabena Buabeng. "Response of benthic invertebrate assemblages to seasonal and habitat condition in the Wewe River, Ashanti region (Ghana)." Open Life Sciences 16, no. 1 (January 1, 2021): 336–53. http://dx.doi.org/10.1515/biol-2021-0040.

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Abstract Aquatic macro-invertebrates play a vital role in the food chain of river ecosystem at several trophic guilds and consumer levels, and are used as biomonitoring tools for aquatic ecosystem health. However, hydrologic conditions of these ecosystems have been severely altered because of the increase in urban development and agricultural expansion. This study examined benthic invertebrate response to processes that structure their community in the Wewe River, segmented into intact, medium, and severe condition zones. We sampled in 100 stations in a period of 4 months in the wet (June–September, 2019) and 3 months in the dry (January–March, 2020) seasons. Geometric series, rarefaction, and Hill numbers models were used to quantify invertebrate assemblages, while ordination technique, canonical correspondence analysis, was used to evaluate the influence of predictive factors on their assemblages. A total of 2,075 individuals belonging to 20 family taxa were registered. There was no significant difference in benthic assemblages between the dry and wet seasons. Predictive factors accounted for 47.04 and 50.84% variances, respectively. Taxa distribution patterns differed significantly only in the severely disturbed zone during the wet season. Neptidae, Libellulidae, and Chironomidae were the most abundant taxa, indicating their broad range habitat preference and their ability to adapt to seasonal changes. Asellidae and Perlidae were the least detected, suggesting their sensitivity to elevated levels of some water quality parameters. The findings highlight the threats to the benthic community and overall functional state of the Wewe River, with the need to consider the proposed conservation interventions indicated in this study.

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Saigo, Miguel, Mercedes Marchese, and Luciana Montalto. "Dispersal traits as benthic invertebrate assemblage drivers in a neotropical large river." Fundamental and Applied Limnology / Archiv für Hydrobiologie 193, no. 3 (April 21, 2020): 275–83. http://dx.doi.org/10.1127/fal/2020/1236.

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Metacommunity theory is a mechanistic framework that explains the interdependence of local factors and regional processes as community drivers. Recent evidence suggests that dispersal mode is a key trait that potentially affects metacommunity dynamics. We analyzed the distribution patterns of benthic macroinvertebrates with different dispersal modes in the Middle Paraná, a neotropical large river. We assessed the relative importance of local environmental conditions and regional spatial structure as assemblage drivers. Aquatic and aerial dispersers presented Clementsian and Gleasonian structures, respectively. For both groups, local environmental conditions influenced community assembly, and spatial structure (overland distances) also affected the distribution of aerial dispersers. Our study highlights that the role of spatial structure as a driver of benthic metacommunities depends on species' dispersal modes. Aerial dispersers responded to regional spatial variables and it is likely that these organisms are also influenced by mass effects. Our results are consistent with current ideas of metacommunity dynamics in large rivers, where dispersal is not considered to limit the distribution of benthic organisms.

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Kaplanis, Nikolas J., Clinton B. Edwards, Yoan Eynaud, and Jennifer E. Smith. "Future sea-level rise drives rocky intertidal habitat loss and benthic community change." PeerJ 8 (May 29, 2020): e9186. http://dx.doi.org/10.7717/peerj.9186.

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The impacts of sea-level rise (SLR) are likely to be the greatest for ecosystems that exist at the land-sea interface, where small changes in sea-level could result in drastic changes in habitat availability. Rocky intertidal ecosystems possess a number of characteristics which make them highly vulnerable to changes in sea-level, yet our understanding of potential community-scale responses to future SLR scenarios is limited. Combining remote-sensing with in-situ large-area imaging, we quantified habitat extent and characterized the biological community at two rocky intertidal study locations in California, USA. We then used a model-based approach to estimate how a range of SLR scenarios would affect total habitat area, areal extent of dominant benthic space occupiers, and numerical abundance of invertebrates. Our results suggest that SLR will reduce total available rocky intertidal habitat area at our study locations, leading to an overall decrease in areal extent of dominant benthic space occupiers, and a reduction in invertebrate abundances. As large-scale environmental changes, such as SLR, accelerate in the next century, more extensive spatially explicit monitoring at ecologically relevant scales will be needed to visualize and quantify their impacts to biological systems.

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Lecerf, Antoine, Denise Patfield, Anatole Boiché, Miira P. Riipinen, Eric Chauvet, and Michael Dobson. "Stream ecosystems respond to riparian invasion by Japanese knotweed (Fallopia japonica)." Canadian Journal of Fisheries and Aquatic Sciences 64, no. 9 (September 1, 2007): 1273–83. http://dx.doi.org/10.1139/f07-092.

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There are growing concerns about the rapid spread of exotic plants into riparian zones, yet little information is currently available on their influence on stream ecosystems. This study assessed the impact of riparian invasion by Japanese knotweed (Fallopia japonica), an aggressive invader, on leaf litter breakdown and its associated biota (aquatic hyphomycete fungi and benthic invertebrates) in heterotrophic, low-order streams in The Pennines (England) and the Pyrenees (France). Our results suggest that leaf consumers (aquatic hyphomycetes and invertebrate shredders) can readily use knotweed leaf litter even in stream sites where it was not previously present. However, aquatic hyphomycete and invertebrate assemblages differed between stream sites with and without knotweed. Leaf litter breakdown rate and relative abundance of large invertebrate shredders (mainly Trichoptera) were enhanced in the Pyrenean invaded site, whose channel contained a high proportion of knotweed leaf litter, whereas no such effects were observed in The Pennines, possibly because of the less extensive knotweed invasion. Alteration of riparian vegetation by plant invaders could therefore increasingly influence instream community and ecological functions as the severity of invasion rises.

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Moritz, C., D. Gravel, L. Savard, C. W. McKindsey, J. C. Brêthes, and P. Archambault. "No more detectable fishing effect on Northern Gulf of St Lawrence benthic invertebrates." ICES Journal of Marine Science 72, no. 8 (July 16, 2015): 2457–66. http://dx.doi.org/10.1093/icesjms/fsv124.

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Abstract Trawling has been reported worldwide to alter seabed structure, and thus benthic habitats and ecosystems. Usually, a decrease in species richness and biomass is observed, and community structure is modified towards more opportunistic species. The Gulf of St Lawrence (Canada) has been intensely exploited since the 17th century, including net, longline, dredge and trawl fishing activities. Recently, the collapse of groundfish stocks induced a shift in fishing practices toward shrimp trawling, which is currently considered a sustainable fishing activity in the region. However, no long-term study has evaluated the potential effects of trawling disturbances on benthic mega-invertebrates. We investigated whether shrimp trawling had long- (ca. 20 years), mid- (ca. 10 years), and short-term (ca. 4 years) impacts on benthic mega-invertebrate taxa richness, biomass, and community structure. Scientific and fishery trawling data analyses showed that no significant long-, mid-, or short-term effect was detected on taxa richness. Significant but weak effects on biomass and community structure were detected at the mesoscale, i.e. at the scale of fishing grounds. In this long-exploited ecosystem, we suggest that a critical level of disturbance was attained by the first gear passages, which occurred decades ago and had irreversible impacts on the seabed by removing vulnerable taxa and structures that provided three-dimensional habitats. It is likely that benthic communities have subsequently reached a disturbed state of equilibrium on which current trawling disturbance has limited or no further impacts.

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Rennie, Michael D., and David O. Evans. "Decadal changes in benthic invertebrate biomass and community structure in Lake Simcoe." Freshwater Science 31, no. 3 (September 2012): 733–49. http://dx.doi.org/10.1899/11-079.1.

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Jimenez, Andrea, Michael D. Rennie, W. Gary Sprules, and Jake La Rose. "Temporal changes in the benthic invertebrate community of Lake Simcoe, 1983–2008." Journal of Great Lakes Research 37 (January 2011): 103–12. http://dx.doi.org/10.1016/j.jglr.2010.07.002.

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Knight, Jennifer C., Brian P. O'Malley, and Jason D. Stockwell. "Lake Champlain offshore benthic invertebrate community before and after zebra mussel invasion." Journal of Great Lakes Research 44, no. 2 (April 2018): 283–88. http://dx.doi.org/10.1016/j.jglr.2018.01.004.

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Montz, Gary R., Jodene Hirsch, Richard Rezanka, and David F. Staples. "Impacts of Copper on a Lotic Benthic Invertebrate Community: Response and Recovery." Journal of Freshwater Ecology 25, no. 4 (December 2010): 575–87. http://dx.doi.org/10.1080/02705060.2010.9664407.

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CARTER, J. L., S. V. FEND, and S. S. KENNELLY. "The relationships among three habitat scales and stream benthic invertebrate community structure." Freshwater Biology 35, no. 1 (February 1996): 109–24. http://dx.doi.org/10.1046/j.1365-2427.1996.d01-450.x.

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Vieira, N., and F. Amat. "The invertebrate benthic community of two solar salt ponds in Aveiro, Portugal." International Journal of Salt Lake Research 5, no. 4 (December 1996): 281–86. http://dx.doi.org/10.1007/bf01995382.

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Wilson, Matthew J., Matthew E. McTammany, and Hannah R. Bohr. "Manganese oxides as localized drivers of benthic invertebrate density and community structure." Hydrobiologia 838, no. 1 (May 29, 2019): 85–98. http://dx.doi.org/10.1007/s10750-019-03979-3.

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Dahl, Jonas. "The impact of vertebrate and invertebrate predators on a stream benthic community." Oecologia 117, no. 1-2 (November 17, 1998): 217–26. http://dx.doi.org/10.1007/s004420050651.

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Solan, Martin, Ellie R. Ward, Christina L. Wood, Adam J. Reed, Laura J. Grange, and Jasmin A. Godbold. "Climate-driven benthic invertebrate activity and biogeochemical functioning across the Barents Sea polar front." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2181 (August 31, 2020): 20190365. http://dx.doi.org/10.1098/rsta.2019.0365.

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Abstract:

Arctic marine ecosystems are undergoing rapid correction in response to multiple expressions of climate change, but the consequences of altered biodiversity for the sequestration, transformation and storage of nutrients are poorly constrained. Here, we determine the bioturbation activity of sediment-dwelling invertebrate communities over two consecutive summers that contrasted in sea-ice extent along a transect intersecting the polar front. We find a clear separation in community composition at the polar front that marks a transition in the type and amount of bioturbation activity, and associated nutrient concentrations, sufficient to distinguish a southern high from a northern low. While patterns in community structure reflect proximity to arctic versus boreal conditions, our observations strongly suggest that faunal activity is moderated by seasonal variations in sea ice extent that influence food supply to the benthos. Our observations help visualize how a climate-driven reorganization of the Barents Sea benthic ecosystem may be expressed, and emphasize the rapidity with which an entire region could experience a functional transformation. As strong benthic-pelagic coupling is typical across most parts of the Arctic shelf, the response of these ecosystems to a changing climate will have important ramifications for ecosystem functioning and the trophic structure of the entire food web. This article is part of the theme issue ‘The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.

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Journal articles on the topic 'Benthic invertebrate community'

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