Distribution Of Benthic Macroinvertebrates Research Articles

Response of Chironomids (Diptera, Chironomidae) to Environmental Factors at Different Spatial Scales.

Factors responsible for species distribution of benthic macroinvertebrates, including responses at different spatial scales, have been previously investigated. The aim of the present research was to review the most relevant factors explaining chironomid species distribution focusing on factors operating at different spatial scales, such as latitude, longitude, altitude, substrate, salinity, water temperature, current velocity, conductivity, acidity, dissolved oxygen, nutrient content etc. acting at regional levels and at a large or small water basin level. Data including chironomid species abundances from different lentic and lotic waters in Italy and other surrounding countries were analyzed using partial canonical correspondence analysis (pCCA) and multiple discriminant analysis (DISCR). Spatial analyses, including univariate Moran's I correlograms, multivariate Mantel correlograms and Moran's eigenvector maps (MEMs), were thereafter carried out. The results showed that habitat type, including different types of lotic waters (i.e., kryal, crenal, rhithral, potamal) and different lake types (i.e., littoral, sublittoral, profundal zones), is the most significant factor separating chironomid assemblages, while spatial factors act only as indirect influencers.

Ecological Influence of Organic Pollution on the Distribution of Benthic Macroinvertebrates in Some Control Forest Watercourses in Cameroon

Monitoring of water quality and distribution of some benthic macroinvertebrates was carried out in a few control watercourses in the Mefou watershed, from August 2022 to June 2023 with the aim of identifying some ecological factors that influence the distribution of benthic organisms in forest areas. The evaluation of granulometric and physicochemical quality was carried out following the appropriate methods and the collection of benthic organisms following the multihabitat approach. The analysis of the particle size parameters shows that the coarse fraction dominates all the points explored, although the beginning of siltation was observed in the middle part of the Abouda and Fam rivers. Physico-chemical analyses revealed a relatively stable environment with well-oxygenated water, low values of organic pollution indicator parameters and low and constant temperatures throughout the watersheds. The analysis of the biological structure shows a total of 8483 individuals collected, all belonging to the arthropod phylum and the insect class. From the orders obtained, Hemiptera dominate the benthic fauna with 6 identified families. The organisational structure of the benthic community was analysed through the calculation of diversity and fairness indices and allows us to affirm that the benthic macroinvertebrate community is diverse and well organised.

Inventory and Distribution of Benthic Macroinvertebrates, Indicators of Water Quality in Four Forested Watercourses in Centre Region of Cameroon

Inventory and Distribution of Benthic Macroinvertebrates, Indicators of Water Quality in Four Forested Watercourses in Centre Region of Cameroon

Distribution of invasive Procambarus clarkii (Girard, 1852) (Decapoda: Astacidea: Cambaridae) in South Korea, with a study of the spatial variation of benthic macroinvertebrate taxa

Abstract The introduction and spread of non-native species pose major threats to biodiversity and ecosystem stability. We conducted a study to assess the spread, growth rate, and interactions of the exotic crayfish Procambarus clarkii (Girard, 1852) throughout South Korea. A total of 343 individuals (223 from reservoirs, 120 from streams) were studied in four provinces. This species has expanded its distribution to 24 regions in South Korea. The length-weight relationship indicated positive allometric growth, expressed as W = 2.855L3.0073. The highest number of adult P. clarkii individuals eradicated was 11,438 in 2022. Using the MaxEnt model and environmental variables related to the climate, a highly accurate forecast was generated for the potential distribution of P. clarkii in South Korea. The factors influencing the current distribution probability were identified as the highest temperature of the warmest month, mean temperature of the wettest quarter, and mean temperature of the warmest quarter, which contributed the most to the present distribution probability. The predicted distribution indicated a rapid increase in P. clarkii density in the southwestern region, extending towards the southeastern and central regions, including the brackish zone. Non-metric multidimensional scaling analysis (stress = 0.07) was conducted based on benthic macroinvertebrates, revealing distinct variations among the four sampling sites. The distribution of benthic macroinvertebrates was significantly influenced by the proportion of sand in the substrate (R = 0.39, P < 0.05) and water quality as estimated by the electrical conductivity (R = 0.51, P < 0.05).

Analysis of environmental factors in sediment based on benthic macroinvertebrates in streams, Korea

AbstractThis research summarizes the data on benthic macroinvertebrates collected in the 15 streams during spring (June) and fall (September–October) of 2022. The objectives of this study were (i) to evaluate the quality of surface waters, sediments, and benthic macroinvertebrates; and (ii) to compare the relationship with the environmental variables in water, sediments and benthic macroinvertebrates that inhabit 15 streams. A total of 114 taxa were collected. The assemblages from the 15 sites were dominated by Chironomidae and Tubificidae, especially Chironomidae constituted 45.0% density occurrence. The low grades of Benthic Macroinvertebrate Index (BMI) were calculated in 10 sites with disturbed (“poor” or “very poor”). Low BMI sites mostly showed Tubificidae or Chironomidae dominant characteristics. The biological indices, BMI, % Tubificidae, and % Chironomidae, were significantly correlated with DO and conductivity. DO was also significantly correlated with all the benthic macroinvertebrate factors and diversity except percent Tubificidae. The heavy metal parameters were correlated mostly with species number, BMI, and diversity index. The objectives of this study examine the diversity of benthic macroinvertebrate in the 15 streams and investigate the relative importance of environmental quality for benthic macroinvertebrate distribution.

Altitudinal and seasonal distribution of benthic macroinvertebrates in River Tons - a tributary of Yamuna River, Uttarakhand, India.

The main tributary of the Yamuna, the Tons River, exhibits altitudinal changes in its macroinvertebrate community's diversity, abundance, and composition. Between May 2019 and April 2021, the study was conducted in the upper section of the river. A total of48 numbers of taxa from 34 families and ten orders were recordedduring the investigation. At this elevation of 1150 to 1287m, the two most predominant orders are Ephemeroptera (32.9%) and Trichoptera (29.5%). During the premonsoon season, they had the lowest macroinvertebrate density (250-290 individuals/m2), and the post-monsoon season had the highest density (600-640 individuals/m2). During the post-monsoon season, the maximum larval forms (60%) of various insect orders were predominant. The findings indicated that lower altitudes (1150-1232m) have higher macroinvertebrate abundance than higher ones. The diversity of dominance is shallow at site-I (0.0738) and strong at the site-IV during the premonsoon season (0.03837). Taxa richness, as measured by the Margalef index (D), peaked in the spring season (January to March) at 6.9 and reached its lowest point (5.74) in the premonsoon season (April to May). Only 16 taxa were discovered in site-I and site-II, but 39 taxa were discovered at low altitudes (site-IV, 1100m) (1277-1287m). The Tons River contains a total of 12 and 13 genera, respectively, that belong to the orders Ephemeroptera and Trichoptera, according to qualitative study of the macroinvertebrates. The current study supports the use of macroinvertebrates as bioindicator species for monitoring biodiversity and assessing the health of ecosystems.

Influence of granulometry on the distribution of benthic macro invertebrates in some streams of the Mvilla and Haut-Nyong watersheds in Cameroon

This study was conducted from November 2018 to October 2019 in 8 forested streams in the Haut-Nyong and Mvilla watersheds to determine the influence of substrates granulometry on benthic macroinvertebrates. The physicochemical analyses showed highly oxygenated, weakly mineralized and slightly acidic waters. The granulometric analyses reveal 9 categories of substrates depending on the scale of sand, sand+gravel or sand+mud. Sampling of benthic macroinvertebrates allowed the collection of 15058 organisms divided into 5 classes, 14 orders and 49 families. The results showed a taxonomic richness strongly influenced by the nature of the substrate. The combination of coarse sand + silt + dead leaves was more favored the development of benthic macroinvertebrates with 48 families. The taxonomic richness associated to the different index revealed good ecological quality of Sounou, Bengo'o and Lo'o rivers.

Effects of trace elements on benthic macroinvertebrate distribution in the sediments of two rivers in the Olifants River Basin, South Africa

Many freshwater ecosystems are facing ecological challenges such as influx of trace elements from human activities, and sediments behave as a sink for trace elements in these environments. Trace element contamination in river sediments is a major environmental concern due to its devastating effect on benthic organisms. The aim of this study was to assess the effect of trace elements in sediments on the distribution of benthic macroinvertebrates in the Blyde and Mohlapitsi rivers of the Olifants River Basin, South Africa. Sediment samples and benthic macroinvertebrates were collected from six sites along each river. The results showed variations in the concentration of the trace elements in the sediment and the distribution of benthic macroinvertebrates among the different sites and between the two rivers. Both rivers recorded high taxa richness and sensitive taxa were well represented in most parts of the rivers, an indication that the rivers are not highly disturbed. There were insignificant correlations between most of the trace elements and the abundance of the benthic macroinvertebrates, though some taxa showed significant correlations with the trace elements. Despite the low impact of the trace elements on the distribution and diversity of benthic macroinvertebrates, ecological health of the rivers and structural distribution of macroinvertebrates may be affected in the future due to increasing human activities in the catchments. It is therefore recommended that effluents from human activities should be controlled to prevent a further degradation of the rivers to protect macroinvertebrates and other aquatic biota.

Impacts of cotton production on the diversity and distribution of benthic macroinvertebrates in the Alibori and Sota rivers in northern Bénin

Impacts of cotton production on the diversity and distribution of benthic macroinvertebrates in the Alibori and Sota rivers in northern Bénin

Benthic Macroinvertebrates in fish spawning grounds, diversity and spatial distribution, Buyo lake dam (Côte d'ivoire)

This work focuses on the diversity and spatial distribution of benthic macroinvertebrates in the ichthyological spawning grounds of Lake Buyo. Sampling took place from June 2018 to May 2019 on 11 spawning grounds using a Van Veen grab, a dip net and a dip net. A total of 19,940 individuals grouped into 28 Families, 13 Orders, 6 Classes and 4 Branches were identified. The most abundant Families with a percentage higher than 20 in the study area are Thiaridae (63.33%) and Chironomidae (22.88%). The Insects class is the most diversified with 17 families followed by Gastropods with 8 families. The values of the Shannon-Weaver indices and the Pielou equitability calculated are low, which reflects a low taxonomic diversity and an imbalance in the spatial distribution of benthic macroinvertebrates in the different ichthyological spawning grounds.

Distribution of benthic macroinvertebrates in relation to physicochemical parameters and macrophyte cover in the Ketar River, Ethiopia

The aim of this study was to determine the effects of physicochemical parameters and macrophyte on the macroinvertebrate assemblages in the Ketar River, which drains into Lake Ziway. Six sampling sites were selected along the river stretch and samples were collected from December to April 2017/2018 based on the method outlined in Ontario Benthos Biomonitoring Network Protocol Manual. A total of 5,450 individuals comprised of one class, 7 orders, and 23 families were collected during the study period. Hemiptera families were the predominant taxa and contributed the largest percentage of the total samples followed by the Coleoptera. Notonectidae and Corixidae shared the highest total abundance. This study confirmed that the sites covered with macrophytes were significantly different from the substrate both in taxa richness and total abundance (P < 0.05). Redundancy Analysis revealed that pH, Temperature, electric conductivity, DO, NO2, NO3, NH4, SiO2 and TP were the most important variables explaining the variation in macroinvertebrate assemblage patterns. The mean Shannon diversity index also indicated that the sites covered by the macrophyte stand had a significantly higher value than the sites sampled from the substrate, which implies that macrophytes support abundant, and promoting the diversity of macroinvertebrates. Thus, the conservation of macrophytes can enhance the conservation of macroinvertebrates along the course of the river, besides the role of macrophyte in sediment trapping and reducing sedimentation buildup in Lake Ziway.

Characterization by benthic macroinvertebrates and some environmental factors of streams in the East Cameroon region

Macrobenthic fauna have recently been widely used as bio-indicators for their ability to reflect the various disturbances in aquatic ecosystems. They have recently been used to assess the ecological health of streams in the East Cameroon region. This study aims to reveal the ecological health of four streams by studying the variations in the population of benthic macroinvertebrates collected in them. Sampling was done from December 2018 to December 2019 for a total of 13 months spread over four collection seasons. Kohonen's self-organising map (SOM) was performed for the various distribution patterns of the organisms collected. Discriminant factor analysis (DFA) was used to identify the parameters that characterise these patterns observed in the environment. Four groups of macrobenthic populations were observed. The distribution of benthic macroinvertebrates in these streams was spatial, temporal and discriminated by variable mineralization parameters and sediment grain size. The distribution of taxonomic richness is linked to the environmental conditions of the stations, which appear to be more or less stable, highlighting a stress gradient on the organisms. The station (Sen3), with unstable conditions, is the site of anthropic activities due to its proximity to residential areas, which are enriched in organic matter and, as a result, abound in pollutant-resistant species such as diptera (Chironomus holomelas, Chironomus sp1 and Chironomus sp2). The population of the other well differentiated groups is subject to light anthropogenic disturbance.

Intertidal macroinvertebrate community structure in a subtropical channel is driven by sediment properties across different land-use types.

Macroinvertebrate community in the intertidal setup plays an important role in coastal ecosystem functions and biogeochemical cycle. However, different land use pattern may influence on their community structure, diversity, and composition in the coastal ecosystems. Using Van-Veen grab sampler, 60 sediment samples wereseasonally collected from mangroves-dominated, aquaculture-dominated, and anthropogenically affected area in the lower intertidal zone of the Kohelia channel of Bangladesh, the Northern Bay of Bengal. We have tasted the variation in sediment properties across three land-use types in this intertidal habitat. To understand the patterns of benthic macroinvertebrate distribution, a neutral community model was applied. Our results showed that community composition and biodiversity of the benthic macroinvertebrate communities varied significantly between mangrove-dominated area with anthropogenically affected areas among the four seasons. The neutral community model revealed that community assembly of benthic macroinvertebrates in the lower intertidal habitats is structured by stochastic processes while sediment properties have significant influence on species distribution and interactions. Results suggested that land-use changes altered sediment properties and could change the diversity and distribution of the macroinvertebrate communities in the lower intertidal habitats.

Effects of Groundwater Inputs to the Hydraulic Circulation, Water Residence Time, and Salinity in a Moroccan Atlantic Lagoon

The finite element model SHYFEM was used to study the hydrodynamics and variability of water level, salinity, temperature, and water residence time (WRT) in the Oualidia lagoon located on the Moroccan Atlantic coast. The lagoon hosts a RAMSAR convention-protected area and also offers a set of valuable ecosystem services providing the source of income for the local population. To assess the effects of submarine groundwater discharge (SGD) inputs in the study area, four simulations were set up using different SGD inputs estimates in addition to tidal forcing, bathymetry, meteorological data including solar radiation, rain, and wind, in addition to boundary conditions in the Atlantic such as salinity, water level, and water temperature. The model was calibrated and validated using hydrodynamic measurements of previous studies in 2012 and 2013. The final results from the model are in good agreement with measured data. The simulation with SGD input ~0.05 m3 s−1 produced salinity values closest to the observed ones. Calculated spatial distribution of WRT, temperature, and salinity reduced to coordinates in two PCA axes is consistent with lagoon zones developed earlier using the benthic macroinvertebrate distribution. The calculated spatial distribution of WRT allowed us to evaluate the placement of oyster aquaculture farms and small-scale fisheries in relation to water quality issues existing in the lagoon.

Influence of the Mekin hydroelectric dam on the distribution of benthic macroinvertebrates of the Dja stream: South Cameroon region

This work was conducted with the aim of studying the biodiversity of benthic macroinvertebrates in the Dja River and determining the effect of the Mekin hydroelectric dam on their population in relation to the physico-chemical quality of the water. The study ran from May to October 2020 and samplings were carried out on a monthly basis in four different sampling stations located upstream and downstream of the dam. The physico-chemical analyses were done according to standard methods, while the benthic macrofauna was collected using a turbid net of 400 µm mesh size over a total area of about 6 m2 per station. Physico-chemical analyses revealed a decreasing evolution from upstream to downstream of the dam of nitrogen forms (NO3- (1.67mg/L-0.41mg/L); NH4+ (0.31 mg/L-0.21 mg/L) with p>0.05); Electrical Conductivity (21.45µS/Cm-17.1µS/Cm with p<0.05) and Suspended Solids (11.10mg/L-6.57mg/L with p<0.05); while Dissolved Oxygen (49.82%-78.23% with p<0.05) and velocity (0.04m/s-0.23m/s) increased. Organic Pollution Index revealed that the water was moderately polluted (3-4). In total, 1894 individuals, of which 1044 belonging to 2 phyla, 2 classes, 6 orders, 27 families and 47 genera/species were collected upstream; and 850 belonging to 3 phyla, 4 classes, 8 orders, 28 families and 45 genera/species were collected downstream. Odonata was largely abundant and highly represented Trithemis dorsalis (96.05%); while downstream, Heteroptera was largely abundant and highly represented by Poissonia sp1. (79.78%). These results revealed that restoration of the upstream of the dam impacted by organic pollution and physical degradation of the environment is recommended.

Influence of the Mekin hydroelectric dam on the distribution of benthic macroinvertebrates of the Dja stream: South Cameroon region

Influence of the Mekin hydroelectric dam on the distribution of benthic macroinvertebrates of the Dja stream: South Cameroon region

Benthic macroinvertebrates diversity and quality of water in first-order streams of Badiyar Gad, lesser Himalaya, Uttarakhand, India

ABSTRACT First-order streams serve as a nursery of macroinvertebrates which act as secondary producers in the aquatic food chain and indicators of water quality. The present investigation conducted on three first-order streams of Badiyar Gad revealed Trichoptera to be the most diverse order followed by Ephemeroptera, Diptera, Coleoptera, Odonata, Lepidoptera, Plecoptera, Hemiptera, Arhynchobdellida, and Decapoda, indicating good water quality for these streams. High density, diversity, and even distribution of benthic macroinvertebrates during the winter season indicated stable ecosystems and healthy water quality. The presence of 35 families and 52 genera indicates a good habitat with numerous ecological niches for the macroinvertebrates. Two genera Maruina and Neophylax were identified as unique in these streams. They have not been previously reported from the Garhwal Himalayan streams.

Species Composition of Benthic Macroinvertebrate and Water Evaluation at the Baekyeok Stream in Korea

This study was conducted to investigate water quality evaluation using benthic macroinvertebrates at a mountain torrential river (Baekyeok Stream in South Korea). All individuals collected from the protocols of the USEPA Rapid Bioassessment Protocol III (RBP III) for benthic macroinvertebrates. In total, 841 individuals belonging to 37 species of 27 families were collected from the Baekyeok Stream. Arthropoda exhibited greatest species diversity with 26 species identified, followed by Mollusca (5 species) and Annelida (5 species). Platyhelminthes accounted for only one family for four seasons within the four studied areas. Total ecological score of benthic macroinvertebrate community (TESB) was varied from 79 (upper region, St. A) to 56 (low region, St. D) with a mean of 70.8. Benthic macroinvertebrate index (BMI) was varied from 47.130 (St. D) to 62.354 (St. A) with a mean of 53.158. Classification of saprobity based on Shannon-Weaver s diversity (H ) was varied from 2.189 to 2.802 with a mean of 2.723. Thus, water quality evaluation was β -mesosaprobic at all stations according to saprobic value. In conclusion, the water quality scores of upper region at Baekyeok Stream was slightly better than those of low region. Judging only the distribution of benthic macroinvertebrates, the water quality of Baekyeok Stream was not so good.

DISTRIBUTION OF BENTHIC MACROINVERTEBRATES ALONG SEDIMENT GRADIENTS IN A MOUNTAIN LAKE OF KUMAUN HIMALAYAS, INDIA

Distribution of benthic macroinvertebrates with sediment characteristics was determined in Lake Sattal of Kumaun Himalayas, India. Sampling was undertaken monthly for two consecutive years at four sites using Ekman dredge bottom sampler. A total of 31 benthic macroinvertebrates species belonging to 10 groups viz, Diptera (5), Trichoptera (5), Gastropoda (4), Ephemeroptera (3), Hirudinea (3), Odonata (3), Coleoptera (2), Decapoda (2), Oligochaeta (2), and Platyhelminthes (2) were collected. Temporal and spatial variations of sediment grain sizes, total organic matters, dissolved oxygen (DO) at the near-bottom layer (NBL) were estimated. Our study reveals that the diversity of macroinvertebrates was higher at the stable medium-sized particles and reduces in coarser-grained sediment bed. Although organic matter regulates the abundance of both sensitive insect larvae and pollution tolerant chironomids, the two groups have different habitat preferences and functional feedings. Increased detrital inputs and periodical anoxia at near bottom layer (NBL) augmented the domination of deposit-feeders. Changes in the land-use pattern in the catchment alter the habitat structures and enhance basal resources segregation in the upland lake. Therefore, determination of habitat-specificity of benthic macroinvertebrates could develop priority efforts to protect the mountain ecosystem.

The lentic and lotic characteristics of habitats determine the distribution of benthic macroinvertebrates in Mediterranean rivers

Abstract The importance of flow‐related factors to benthic organisms, as well as the role of habitat conditions in shaping aquatic communities during low‐flow periods, have been recognised. Despite this, the preferences of macroinvertebrates to the ratio of lentic to lotic habitats at the reach scale have not been accurately quantified in most instances. Aquatic invertebrates and habitat features in a range of temporary rivers in Sardinia were investigated. The investigation focused on the flow‐related characteristics that contribute to defining the lentic–lotic condition of the river reaches. The relation of habitat features to benthic taxa distributions was assessed using multidimensional scaling. The main aim of the paper was to quantify the responses of taxa to the different lentic and lotic habitat conditions by applying hierarchical logistic regressions. Finally, taxon optima were aligned along the lentic–lotic gradient and the responses of different taxonomic groups compared. Unbroken waves and imperceptible flow were correlated with benthic taxa variability, suggesting local hydraulics and turbulence have a major role in regulating community composition. The overall lentic–lotic character of the river reaches was also clearly related to the benthic taxa distribution. More than 80% of taxa were significantly related to the lentic–lotic gradient, and an asymmetrical response curve was the predominant model. Benthic groups showed taxon optima clustered in different ranges of the lentic–lotic gradient. Odonata, Coleoptera, Hemiptera, and Mollusca preferred clearly lentic conditions. Diptera mainly ranged on the lotic side of the gradient, while Trichoptera were relatively uniformly distributed across the gradient. Ephemeroptera taxa clustered in intermediate lentic–lotic conditions, with two species preferring extremely lentic habitats. In general, optima converged at intermediate and extremely lentic conditions, presumably due, respectively, to the coexistence of different lentic and lotic features and to the highly diverse environmental characteristics under extremely lentic situations. These results support the conclusion that dissimilar ecological factors act on benthic taxa along the lentic–lotic range and species favouring different lentic–lotic conditions are subjected to pressures of different nature. This should not be ignored when defining species preferences and studying community structure or relationships between species in Mediterranean rivers, which cyclically vary their habitat composition. In addition, the uneven distribution of optima of different groups along the lentic–lotic gradient might affect macroinvertebrate metrics when assessing ecological status or establishing reference conditions under variable climatic conditions.