Macroinvertebrate Biodiversity Research Articles

Ecological characterisation of urban ponds in the Netherlands: a study based on data collected by volunteers

Blue space in the urban environment can positively contribute to public health and well-being. Many urban freshwater systems, however, are exposed to anthropogenic stressors, resulting in deteriorated water quality and biodiversity. Private garden ponds are essential elements of this blue space but little is known about their water quality since they are not monitored by water professionals. The Dutch citizen science initiative Waterdiertjes.nl focusses on biological water quality assessment using macroinvertebrates and launched a campaign to investigate garden ponds in 2021. The campaign yielded macroinvertebrate recordings in 60 garden ponds and limited additional information on dimensions, and presence of water vegetation and fish. Volunteers also investigated 92 public urban ponds in 2021. Combining both data allowed for evaluation of the similarity between both pond types. Analyses were also performed to discover the importance of pond dimensions and presence of aquatic vegetation or fish for the macroinvertebrate biodiversity and water quality. Multivariate analyses showed a considerable overlap in macroinvertebrate community composition between garden and public urban ponds. Results showed high variability in taxon richness, total macroinvertebrate density and water quality scores A significant, nonlinear relation was observed between pond depth and macroinvertebrate taxon richness with the highest richness at a depth of 0.5-1m. Submerged vegetation correlated significantly with taxon richness with little vegetation having the lowest richness. Presence of fish or floating vegetation was not significantly related to taxon richness, total density and water quality scores possibly due to unnatural conditions that underlie in garden ponds. Since water professionals and academic scientists do not monitor garden ponds, citizen science may provide valuable data on water quality and biodiversity in these waters. The present initiative showed that volunteers can successfully monitor understudied ecosystems and gather data on temporal and spatial scales complementary to professional data that lead to new (ecological) insights.

Exploring macroinvertebrate biodiversity in the dynamic southern Balkan stream network of the Vjosa using preservative-based DNA metabarcoding

Reliable biodiversity data are crucial for environmental research and management. Unfortunately, data paucity prevails for many regions and organismal groups such as aquatic invertebrates. High-throughput DNA-based identification, in particular DNA metabarcoding, has accelerated biodiversity data generation. However, in the process of metabarcoding, specimens are usually destroyed, precluding later specimen-based analyses. Metabarcoding of DNA released into the preservative ethanol has been proposed as a non-destructive alternative, but proof-of-principle studies have yielded ambiguous results, reporting variance in detection probability for various taxa and methodological biases. In this study, we tested the performance of preservative-based metabarcoding of aquatic invertebrates in comparison to a standard morpho-taxonomic assessment based on samples from one of Europe’s last free-flowing rivers, the Vjosa. Multi-habitat samples were collected at 43 sites in two seasons and stored in ethanol, after fixation in formaldehyde for morpho-taxonomic analyses. Preservative-based DNA metabarcoding detected three times more taxa but failed to detect other taxa found using the standard method. In addition to incomplete reference data and primer bias that likely precluded the detection of specific taxa, preservative-based DNA metabarcoding cannot provide accurate abundance estimates. However, the metabarcoding data revealed distinct small-scale and large-scale community patterns in the Vjosa river network, which were also recovered by quantitative data of the standard approach. Overall, our results indicate that preservative-based metabarcoding provides important biodiversity data, which could be further improved by quantitative validation. The method is robust and reliable, even though samples were taken under harsh field-conditions and stored without cooling. Further, our results emphasise the need for reliable DNA barcoding reference libraries. Building those may be supported by preservative-based metabarcoding that maintains intact vouchers for subsequent specimen-based analyses.

Catching the Drift of Marine Invertebrate Diversity through Digital Repositories—A Case Study of the Mangroves and Seagrasses of Maputo Bay, Mozambique

Mangroves and seagrasses present with high marine macroinvertebrate biodiversity that contributes to their structure and functioning. Macroinvertebrates possess a broad range of functional traits, making them excellent models for biodiversity and available-trait-based studies. This study aimed to characterize the biodiversity of marine macroinvertebrates as two different ecosystems situated along the coastline of Maputo Bay by compiling dispersed data from online databases. Specifically, this study addressed species richness, taxonomic and functional diversity based on two traits (habitat occupation and trophic guild), and the community structure of these traits. Mangroves presented with a higher species richness and taxonomic diversity than seagrasses. The functional diversity of mangroves was mostly explained by the trophic guild trait. In the case of seagrasses, functional diversity was mostly due to differences in habitat occupation in the 20th century, but the trophic guild accounted for this functional diversity from 2000 onwards. The comparison of community compositions between the two ecosystems showed low or no similarity. The use of digital databases revealed some limitations, mostly regarding the sampling methods and individual counts. The trends and data gaps presented in this study can be further used to inform subsequent systematic data acquisition and support the development of future research. A further step that may be taken to improve the use of digital data in future biodiversity studies is to fully incorporate functional traits, abundance and sampling methods into online databases.

Environmental factors are the major drivers of macroinvertebrate assemblage structure in southern Brazilian coastal lakes

AbstractCoastal freshwater lakes are distinctive landscape features in South America, and benthic macroinvertebrates are key to their ecological functioning. Identifying the main factors driving the assemblage structure of benthic macroinvertebrate is thus important for the development of management strategies in these ecosystems. However, studies on the drivers of macroinvertebrate assemblages are scarce in subtropical coastal lakes of the Neotropical region. Here, we evaluated the role of environmental (morphometric and water chemistry variables) and spatial factors in the assemblage structure of benthic macroinvertebrates in 36 coastal freshwater lakes in Brazil from 2008 to 2015. Macroinvertebrate family richness increased with ammonium, pH and water transparency, and decreased with nitrate content (slope ≈1 for all significant variables). Environmental factors explained most of the variation in macroinvertebrate composition (16%) compared to spatial ones (3.4%). In specific, Dugesiidae, Hydrobiidae, Corbiculidae, Sphaeromatidae, Noteridae, Hydropsychidae, Culicidae and Ceratopogonidae predominated in lakes with lower conductivity (<100 μS/cm) and higher water transparency (>1 m). Spatial factors summarized differences in macroinvertebrate assemblages between isolated and connected lakes. Although none of the lakes studied are directly impacted by organic pollution, our results suggest that benthic macroinvertebrate assemblages in subtropical coastal lakes are mostly structured by water chemistry, likely reflecting the major trends in land use along the study region (transition from agriculture to urban areas). We recommend that the conservation of macroinvertebrate biodiversity in southern Brazilian coastal lakes focus on the monitoring of water chemistry factors associated with human‐based land use.

Bio-evaluation of the Ecological Health Status of Petroleum Effluent Receiving Water from Eleme River, Nigeria

The ecological Health Status of Eleme River receiving treated petroleum effluent wastes from Eleme Petroleum Refinery Company was evaluated using a combined approach of biological methods; petroleum effluent bioindicators, functional diversity and community assemblage metrics, and physicochemical methods; TPH, nutrients, turbidity, DO, pH, Heavy metals, and total dissolved solids analysis. This was carried out, knowing that effluent discharges change the biodiversity of aquatic macro invertebrates, particularly insects, reduce their functional roles, and change their physicochemical requirements. The River was divided into 3 stations; upstream (receiving point), midstream, and downstream, with each station further divided into 3 sampling points. The collection of macro invertebrates was done, using handnets and Eckman’s grab from floating vegetation, logs, and sediments. The samples were placed in a 4-L bucket containing 70% ethanol and 5% glycerin and transported to the Entomology Research Laboratory, Department of Animal and Environmental Biology, the University of Port Harcourt for sorting and identification. Composite water samples were taken for analyses of physicochemical properties using standard devices and methods. Results obtained indicated that out of 18 species encountered, 12 were monitor indicators, 5 were facultative tolerant indicators and none were sensitive indicators. Five species (taxa) occurred at both up and mid-streams and seven occurred downstream. Daphnia barbata and macrobranchium sp., occurred commonly in the three stations. The insect indicators encountered were seven, all of the downstream, and were dominated by insects belonging to the order: Hemiptera. Three functional groups; Detritivorous, collector-herbivorous, and predators were encountered with detritivorous being dominant. The TPH, nitrate, phosphate, copper, and nickel concentrations in all sampling stations were above the intervention limits of the World Health Organization (WHO). Concentrations of physicochemical properties except DO and pH were higher downstream. Shannon-Weiner index showed that the absence of species belonging to Ephemeroptera, Plecoptera, and Trichoptera in all stations indicated that Eleme River has a poor ecological health status.

Are we there yet? Management baselines and biodiversity indicators for the protection and restoration of subtidal bivalve shellfish habitats

Biodiversity loss and degradation of natural habitats is increasing at an unprecedented rate. Of all marine habitats, biogenic reefs created by once-widespread shellfish, are now one of the most imperilled, and globally scarce. Conservation managers seek to protect and restore these habitats, but suitable baselines and indicators are required, and detailed scientific accounts are rare and inconsistent.In the present study the biodiversity of a model subtidal habitat, formed by the keystone horse mussel Modiolus modiolus (L.), was analysed across its Northeast Atlantic biogeographical range. Consistent samples of ‘clumped’ mussels were collected at 16 locations, covering a wide range of environmental conditions. Analysis of the associated macroscopic biota showed high biodiversity across all sites, cumulatively hosting 924 marine macroinvertebrate and algal taxa.There was a rapid increase in macroinvertebrate biodiversity (H′) and community evenness (J) between 2 and 10 mussels per clump, reaching an asymptote at mussel densities of 10 per clump. Diversity declined at more northern latitudes, with depth and in coarser substrata with the fastest tidal flows. Diversity metrics corrected for species abundance were generally high across the habitats sampled, with significant latitudinal variability caused by current, depth and substrate type. Faunal community composition varied significantly between most sites and was difficult to assign to a ‘typical’ M. modiolus assemblage, being significantly influenced by regional environmental conditions, including the presence of algal turfs.Within the context of the rapid global increase in protection and restoration of bivalve shellfish habitats, site and density-specific values of diversity are probably the best targets for conservation management and upon which to base monitoring programmes.

Biodiversity of benthic macroinvertebrates in some coastal rivers of the South Cameroon region

Biodiversity of benthic macroinvertebrates in some coastal rivers of the South Cameroon region

Dynamic, downstream‐propagating thermal vulnerability in a mountain stream network: Implications for biodiversity in the face of climate change

AbstractAs climate change continues to increase air temperature in high‐altitude ecosystems, it has become critical to understand the controls and scales of aquatic habitat vulnerability to warming. Here, we used a nested array of high‐frequency sensors, and advances in time‐series models, to examine spatiotemporal variation in thermal vulnerability in a model Sierra Nevada watershed. Stream thermal sensitivity to atmospheric warming fluctuated strongly over the year and peaked in spring and summer—when hot days threaten invertebrate communities most. The reach scale (~ 50 m) best captured variation in summer thermal regimes. Elevation, discharge, and conductivity were important correlates of summer water temperature across reaches, but upstream water temperature was the paramount driver—supporting that cascading warming occurs downstream in the network. Finally, we used our estimated summer thermal sensitivity and downscaled projections of summer air temperature to forecast end‐of‐the‐century stream warming, when extreme drought years like 2020–2021 become the norm. We found that 25.5% of cold‐water habitat may be lost under high‐emissions scenario representative concentration pathway (RCP) 8.5 (or 7.9% under mitigated RCP 4.5). This estimated reduction suggests that 27.2% of stream macroinvertebrate biodiversity (11.9% under the mitigated scenario) will be stressed or threatened in what was previously cold‐water habitat. Our quantitative approach is transferrable to other watersheds with spatially replicated time series and illustrates the importance of considering variation in the vulnerability of mountain streams to warming over both space and time. This approach may inform watershed conservation efforts by helping identify, and potentially mitigate, sites and time windows of peak vulnerability.

A survey of aquatic macroinvertebrates in a river from the dry corridor of Nicaragua using biological indices and DNA barcoding.

Aquatic macroinvertebrates are widely used as indicators for water quality assessment around the world. Modern strategies for environmental assessment implement molecular analysis to delimitate species of aquatic macroinvertebrates. Delimitation methods have been established to determine boundaries between species units using sequencing data from DNA barcodes and serve as first exploratory tools for taxonomic revisions. This is useful in regions such as the neotropics where aquatic macroinvertebrate habitats are threatened by human interference and DNA databases remain understudied. We asked whether the biodiversity of aquatic macroinvertebrates in a stream in Nicaragua, within the Central American Dry Corridor, could be characterized with biological indices and DNA barcoding. In this study, we combined regional biological indices (BMWP-CR, IBF-SV-2010) along with distance-based (ASAP, BIN) and tree-based (GMYC, bPTP) delimitation methods, as well as nucleotide BLAST in public barcode databases. We collected samples from the upper, middle, and low reaches of the Petaquilla river. The three sites presented excellent water quality with the BMWP-CR index, but evidence of high organic pollution was found in the middle reach with the IBF-SV-2010 index. We report a total of 219 COI sequences successfully generated from 18 families and 8 orders. Operational taxonomic units (OTUs) designation ranged from 69 to 73 using the four methods, with a congruency of 92% for barcode assignation. Nucleotide BLAST identified 14 species (27.4% of barcodes) and 33 genera (39.3% of barcodes) from query sequences in GenBank and BOLD system databases. This small number of identified OTUs may be explained by the paucity of molecular data from the Neotropical region. Our study provides valuable information about the characterization of macroinvertebrate families that are important biological indicators for the assessment of water quality in Nicaragua. The application of molecular approaches will allow the study of local diversity and further improve the application of molecular techniques for biomonitoring.

Nonlinear effects of environmental drivers shape macroinvertebrate biodiversity in an agricultural pondscape.

Agriculture is a leading cause of biodiversity loss and significantly impacts freshwater biodiversity through many stressors acting locally and on the landscape scale. The individual effects of these numerous stressors are often difficult to disentangle and quantify, as they might have nonlinear impacts on biodiversity. Within agroecosystems, ponds are biodiversity hotspots providing habitat for many freshwater species and resting or feeding places for terrestrial organisms. Ponds are strongly influenced by their terrestrial surroundings, and understanding the determinants of biodiversity in agricultural landscapes remains difficult but crucial for improving conservation policies and actions. We aimed to identify the main effects of environmental and spatial variables on α-, β-, and γ-diversities of macroinvertebrate communities inhabiting ponds (n=42) in an agricultural landscape in the Northeast Germany, and to quantify the respective roles of taxonomic turnover and nestedness in the pondscape. We disentangled the nonlinear effects of a wide range of environmental and spatial variables on macroinvertebrate α- and β-biodiversity. Our results show that α-diversity is impaired by eutrophication (phosphate and nitrogen) and that overshaded ponds support impoverished macroinvertebrate biota. The share of arable land in the ponds' surroundings decreases β-diversity (i.e., dissimilarity in community), while β-diversity is higher in shallower ponds. Moreover, we found that β-diversity is mainly driven by taxonomic turnover and that ponds embedded in arable fields support local and regional diversity. Our findings highlight the importance of such ponds for supporting biodiversity, identify the main stressors related to human activities (eutrophication), and emphasize the need for a large number of ponds in the landscape to conserve biodiversity. Small freshwater systems in agricultural landscapes challenge us to compromise between human demands and nature conservation worldwide. Identifying and quantifying the effects of environmental variables on biodiversity inhabiting those ecosystems can help address threats impacting freshwater life with more effective management of pondscapes.

IMPACT OF ECOHYDROLOGICAL INTERVENTIONS ON MACROINVERTEBRATE DIVERSITY ASSOCIATED WITH PHYSICOCHEMICAL PARAMETERS ON THE WETLANDS ALONG THE SOUTHEASTERN SHORE OF LAKE TANA, ETHIOPIA

Biological indicators have the improvement of monitoring ecological conditions and to measure of anthropogenic impacts on aquatic ecosystems. This indicates that appropriate wetland management mitigation measures that should be implemented in degraded wetlands to conserve biodiversity and improve water quality. The aim of the study was to investigate the impacts of ecohydrological intervention in relation to macroinvertebrate diversity and relate macroinvertebrate diversity with physicochemical parameters of the wetland in Lake Tana shore intervention site. Sampling stations were selected according to vegetation gradient. The sampling procedure employed using quadrats along transects following the main ecological gradient of water depth and vegetation structure and growth form. Four quadrats at every 25m distance were laid at each transect. A total of 24 quadrats of 1m x1m size were taken. Collected samples of each quadrat were pooled to represent each sampling site. One way ANOVA was further done to test any significant variation in macroinvertebrate and physiochemical attributes among stations. The Hilsenhoff Family-level Biotic Index (HFBI) was calculated for macroinvertebrate families. The HFBI index was analyzed and identified 975 macroinvertebrate individuals belonging to 15 families which were collected from all sampling sites during the study period, and the most dominant family were Hydrophilidae Coenagrionidae and Physidae. Based on the Shannon diversity index, the Gumetirs wetland was grouped under good ecological condition as compared to the remaining two reference wetlands. There was a significant variation in abundance and biodiversity of macroinvertebrates among sampling sites and better conditions exist at the intervention site. The correlation analysis between physicochemical parameters and macro-invertebrate abundance showed that organic carbon and temperature are most likely positively correlated with macroinvertebrate abundance. Thus, high macroinvertebrate diversity indicated that wetlands found in a good ecological condition.

Occurrence of organic pollutants in the River Itchen and River Test—two chalk streams in Southern England, UK

The River Itchen and River Test, two chalk streams in Southern England, are sites of special scientific interest. These ecosystems face a number of environmental pressures from anthropogenic inputs of organic pollutants. Hence, we investigated the occurrence of these chemicals within the two catchments. Spot water samples (1 L) were collected at nineteen sites along the catchment on two occasions (March and June 2019). Samples were extracted (HLB-L sorbent disks) and analysed using high-resolution liquid chromatography-quadrupole-time-of-flight mass spectrometry and gas chromatography-mass spectrometry. Compounds were identified against commercially available databases. Using this approach, we found 115 pharmaceutical and personal care products, 81 plant protection products and 35 industrial chemicals. This complex mixture of pollutants covered a range of physico-chemical properties and included priority substances in the EU Water Framework Directive or currently on the third Watch List. Both rivers had similar chemical profiles for both months. Herbicides and fungicides were dominant in the spring, whereas insecticides occurred more frequently in the summer. Point discharges from wastewater treatment plants were the main source of pharmaceutical and personal care products. Agricultural activities were the main contributor to the presence of plant protection products. The impact of these organic chemicals on the ecology, particularly on macroinvertebrate biodiversity, is unknown and warrants further investigation. Our suspect screening approach could guide future toxicological investigations to assess the environmental impacts of these diverse chemicals.

Management of Developmental Assessment In Improving The Quality of Learning for Students With Special Needs In Inclusive Schools

The present study reports the first comprehensive study on the freshwater macroinvertebrates and its habitat preferences in Bilah River, the largest riverin the Northern Sumatra. The riverside is characterized by the presence of anthropogenic and industrial activities which may alter the macroinvertebrate assemblage and biodiversity. Five months of investigation on 10 sampling stations from December 2016 to October 2017 was conducted based on the river flow in Bilah River. Principal component analysis indicated a decrease in trophic status from upstream to downstream of the river. A total of 27 taxa were recorded, with the most abundant group The developmental task of a child is something that appears at a certain period in the life span, if one phase fails it will cause various difficulties in completing the next phase of development. This is experienced by students with special needs (PDBK). Currently, the reality of teachers in the field is that they do not understand how to identify and assess these developmental phases for GDPK, which is a prerequisite for supporting success in the academic field. The purpose of this study was to find out how the implementation of developmental assessments in the two inclusive organizing schools, Ibnu Sina and Mutiara Bunda, in finding the actual GDPK profile through the “Daming Cycle” management theory approach from W. Edward Daming. In particular, this study describes and analyzes (1) plan, (2) Do, (3) Check and (4) action on developmental assessment using Sallis Edward's quality theory and Huvinggurst's developmental theory. This study uses a descriptive method with a qualitative approach. Collecting data by conducting observations, interviews, and study of documentation and validation of research results by conducting FGD (forum group discussion). The results of the study indicate that the management of developmental assessments at the inclusive schools of Ibnu Sina and Mutiara Bunda has been carried out by adjusting the existing concept rules, although in its implementation there are still obstacles, especially in terms of parental commitment and teacher understanding in GDPK confectionery.

Environmental DNA (eDNA) metabarcoding surveys show evidence of non-indigenous freshwater species invasion to new parts of Eastern Europe

Active environmental DNA (eDNA) surveillance through species-specific amplification has shown increased sensitivity in the detection of non-indigenous species (NIS) compared to traditional approaches. When many NIS are of interest, however, active surveillance decreases in cost- and time-efficiency. Passive surveillance through eDNA metabarcoding takes advantage of the complex DNA signal in environmental samples and facilitates the simultaneous detection of multiple species. While passive eDNA surveillance has previously detected NIS, comparative studies are essential to determine the ability of eDNA metabarcoding to accurately describe the range of invasion for multiple NIS versus alternative approaches. Here, we surveyed twelve sites, covering nine rivers across Belarus for NIS with three different techniques, i.e. an ichthyological, hydrobiological and eDNA survey, whereby DNA was extracted from 500 ml surface water samples and amplified with two 16S rDNA primer assays targeting the fish and macroinvertebrate biodiversity. Nine non-indigenous fish and ten non-indigenous benthic macroinvertebrates were detected by traditional surveys, while seven NISeDNA signals were picked up, including four fish, one aquatic and two benthic macroinvertebrates. Passive eDNA surveillance extended the range of invasion further north for two invasive fish and identified a new NIS for Belarus, the freshwater jellyfish Craspedacusta sowerbii. False-negative detections for the eDNA survey might be attributed to: (i) preferential amplification of aquatic over benthic macroinvertebrates from surface water samples and (ii) an incomplete reference database. The evidence provided in this study recommends the implementation of both molecular-based and traditional approaches to maximise the probability of early detection of non-native organisms.

Flow regimes among rivers influences benthic biota biodiversity, but not abundance or biomass, in intertidal mudflats and sandflats in wet-dry tropical estuaries

Flow is a fundamental driver of ecological processes in river networks and estuaries. In estuaries, river flow interacts with tidal and wave energy to structure the physiochemical environment and the relative strength of these interactions changes in space and time. Thus, ecological processes in estuaries are best understood within the context of these physical processes. In this study, we explore how changes in river flow regime influence the structure of benthic communities in three estuaries in northern Australia's Gulf of Carpentaria. This region resides in the wet-dry tropics and the rivers have among the most variable flow regimes in the world. During two sequential dry seasons, we compared measures of benthic macroinvertebrate biodiversity, abundance, and biomass in intertidal mudflats and sandflats among three estuaries with differing river flow regimes. We found that the number of consecutive days of zero river flow during the preceding dry season best explained inter- and intra-annual patterns in benthic community composition. Specifically, we suggest that the dry season river flow regime dictated the salinity regime of each estuary, which in-turn influenced benthic community composition. However, neither the differences in the salinity regime or community composition influenced total abundance or biomass of the benthic community, indicating that the regional taxa pool currently contains enough functional redundancy to maintain abundances and biomasses under various physicochemical conditions. This in turn provides consistent resources for higher trophic levels such as birds and fish.

Assessment of water quality and overall biodiversity of certain wetlands of Sivasagar urban area

Various physic-chemical parameters such as ph, Dissolved Oxygen (DO), free CO2 are commonly used criteria for water quality assessment. It provides information about the overall health of the water bodies. Biodiversity of macro-invertebrates and physic-chemical water quality parameters of Juliva fishery and Moribeel wetland of Sivasagar district of Assam were assessed from different sampling sites monthly from April, 2017 to April, 2018. By studying macro-invertebrates diversity of the wetland as bioindicator, we have assessed the overall quality of these water bodies, mainly about their pollution status.

Ecological engineering practice of cascade-pond system: Water purification and biodiversity conservation

With the aggravation of agricultural pollution and habitat degradation, ecological engineering has been applied to solve those contradictions. One of the effective strategies for agricultural pollution and biodiversity conservation in hilly areas is to build the cascade-pond system. In this project, the cascade-pond system was built as agricultural facilities for sustainable development in Lieshen village of Liangping district, China. In order to analyze the purification effect of aquaculture pollution and the characteristics of the macroinvertebrate assemblages in the cascade-pond system, aquatic macroinvertebrates and environmental variables were sampled at three times in one year. The results showed that the cascade-pond group in the middle reach had lower purification function to the aquaculture pollution from the upstream fish pond, which might be due to the low concentration of sewage from upstream. Higher concentration of nutrients, little macrophytes and plenty of fish in the fish ponds, did harmful to the macroinvertebrate assemblages. Meanwhile, the cascade-pond group in the middle reach with lower concentration of nutrients, abundant macrophytes and less fish could support higher biodiversity of macroinvertebrates. In the cascade-pond group, with the decrease of nutrients, the productivity of macroinvertebrates was limited by oligotrophic condition. In addition to water purification and biodiversity conservation, the system also could provide ecosystem services as hydrological regulation, soil and water conservation, economic production, leisure and entertainment. The study can offer practical model for sustainable development of agriculture in hilly areas and provide data support for the protection of regional biodiversity.

Ecological Health Assessment of Renuka Lake, Himachal Pradesh, India

Researchers, policymakers, and governments are increasingly interested in assessing the ecological health (EH) of lakes and streams. The EH of a lake can be expressed in terms of water quality, trophic state and biodiversity of riparian vegetation, macroinvertebrates and fishes. The ecological health index (EHI) of Renuka lake, Himachal Pradesh of India, was analyzed based on National Sanitation Foundation Water Quality Index (NSFWQI), Carlson’s Trophic State Index (TSI), Simpson Diversity Index (SDI), and Shannon-Weiner index (SWI). The results of NSFWQI and CTSI are found in the range of 40-59 and 49.9-58.9 respectively indicating that the water quality was poor to medium and not suitable for drinking purposes but can be used for secondary purposes such as agriculture, industry, and recreation etc. The trophic state of the lake is similarly in the eutrophic range, with an overall EHI of 1.81-2.47, indicating poor to medium trophic status. Apart from analyzed results, the EH category from mesotrophic to a eutrophic state of the lake is caused due to the cultural siltation/nutrient loading, religious practices, land tenurial issues, and uncontrolled tourist pressure followed by recreational activities on water bodies and lake vicinity. Accordingly, suitable restoration methods such as source control, desilting/dredging, and lake aquatic plantation are suggested to recover the ecological health of the lake back to a mesotrophic or oligotrophic state.

Improved management of farm dams increases vegetation cover, water quality, and macroinvertebrate biodiversity.

In many farming landscapes, aquatic features, such as wetlands, creeks, and dams, provide water for stock and irrigation, while also acting as habitat for a range of plants and animals. Indeed, some species threatened by land‐use change may otherwise be considerably rarer—or even suffer extinction—in the absence of these habitats. Therefore, a critical issue for the maintenance of biodiversity in agricultural landscapes is the extent to which the management of aquatic systems can promote the integration of agricultural production and biodiversity conservation. We completed a cross‐sectional study in southern New South Wales (southeastern Australia) to quantify the efficacy of two concurrently implemented management practices—partial revegetation and control of livestock grazing—aimed at enhancing the vegetation structure, biodiversity value, and water quality of farm dams. We found that excluding livestock for even short periods resulted in increased vegetation cover. Relative to unenhanced dams (such as those that remained unfenced), those that had been enhanced for several years were characterized by reduced levels of turbidity, nutrients, and fecal contamination. Enhanced dams also supported increased richness and abundance of macroinvertebrates. In contrast, unenhanced control dams tended to have high abundance of a few macroinvertebrate taxa. Notably, differences remained between the macroinvertebrate assemblages of enhanced dams and nearby “natural” waterbodies that we monitored as reference sites. While the biodiversity value of semilotic, natural waterbodies in the region cannot be replicated by artificial lentic systems, we consider the extensive system of farm dams in the region to represent a novel ecosystem that may nonetheless support some native macroinvertebrates. Our results show that management interventions such as fencing and grazing control can improve water quality in farm dams, improve vegetation structure around farm dams, and support greater abundance and diversity of aquatic macroinvertebrates.

Responses of Macroinvertebrate Communities to Hydromorphological Restoration of Headwater Streams in Brittany

Indices of fauna communities, including macroinvertebrates, have been widely used as indicators of environmental changes in streams with great success. However, in the evaluations of in-stream restorations, results from the deployment of macroinvertebrate community indices as bio-indicators have been inconclusive, with scanty evidence for success. This study aims to determine if in headwater streams, and particularly according to the type of in-stream restoration studied (i.e., suppression of concrete pipe), bio-indicators based on macroinvertebrate can be relevant. We monitored three headwater stream reaches where artificial structures constituting hydromorphological impairments to the streams were removed. We collected macroinvertebrate samples from impacted stream sections and control sites established along the streams. Samples were collected before and after the restoration activities, in a before-after-control-impact (BACI) study design. We used two macroinvertebrate-based multimetric tools (I2M2 and ERA) to evaluate the ecological status of the streams, based on macroinvertebrate community indices, and to identify the relative contributions of watershed anthropic pressures to the ecological status. We found that the removal of the artificial structures and the restoration of natural flow were successful in reducing clogging. However, only taxonomic richness showed a positive significant change. The results indicate that the presence of confounding factors, not addressed by the restoration works, may have been responsible for this minimal success in biodiversity recovery. Although the multimetric assessment tools were able to differentiate between streams and disentangle the effects of multiple pressures contributing to degradation in the streams, they were limited to a level below the watershed scale. Our results showed that for a better outcome for macroinvertebrate biodiversity improvement, methods of in-stream restorations must consider the multiple pressures contributing to the degradation of fauna communities in watersheds.