BMWP Index Research Articles

Determination of Water Quality of Susurluk Stream, Çapraz Stream and Karadere Using Macrobenthic Invertebrates and Biotic Indexes

In order to determine the water quality of Susurluk Stream, Çapraz Stream and Karadere, 5207 macrobenthos samples were collected and examined from 14 different stations in two different periods of 2021, and 37 families (Baetidae, Caenidae, Corixidae, Gerridae, Naucoridae, Nepidae, Hydrometridae, Pleidae, Mesovelidae, Coenagrionidae, Libellulidae, Calopterygidae, Cordulegasteridae, Gomphidae, Chironomidae, Stratiomyidae, Sciomyzidae, Ceratopogonidae, Simulidae, Hydropsychidae, Erpobdellidae, Glossiphonidae, Asellidae, Gammaridae, Physidae, Lymnaeidae, Melanopsidae, Planorbidae, Hydrobiidae, Viviparidae, Dytiscidae, Hydrophilidae, Hygrobiidae, Haliplidae, Curculionidae, Noteridae ve Unionidae) belonging to 15 orders were identified. In order to assess water quality, BMWP Original, BMWP Turkish, BMWP Spanish, and ASPT biotic indices were employed. Index results were determined for each station during the first and second periods. Based on these results, five different water quality categories were calculated. Additionally, it was revealed that the Spanish version of the BMWP index can also be utilized in biotic index studies conducted in Turkey.

The river health of Alista River based on macroinvertebrates communities at Selorejo Village Dau Subdistrict Malang Regency

The Alista River is one of the rivers in the upstream Brantas watershed which has relatively natural conditions, but currently there are agricultural activities on the riverbank. The aim of this study was to analyze the health status in Alista River based on the macroinvertebrate communities. This study uses a survey method. Sampling was carried out at 5 stations based on different land use. Sampling of macroinvertebrates used the kicking technique with a hand net with a mesh size of 500 μm in a 10 meter long riffle area. Data analysis used the value of BMWP index (Biological Monitoring Working Party) and the ASPT (Average Score Per Taxon). The results of the identification of macroinvertebrates found were 38 families for instance Glossossomatidae, Lepidosmatidae, and Richardsonianidae. The families belong to 10 orders and 3 classes. The lowest family is 11 families at station 5 (citrus and bamboo gardens). The highest families are 29 families at station 3 (citrus gardens and forests). The results show BMWP-ASPT score ranged from 6.3–4.3 indicating excellent to moderately poor health status. Stations with excellent categories, namely stations 1,2,3,4. Station land use 1,2,3 secondary forest before tourism was discovered including Glossosomatidae. Station 4′s land use is in the form of a tourism location and Lumbriculidae has been found. Stations in the moderately poor category, namely station 5 which is located after tourism sites (citrus gardens and settlements) were found Richardsonianidae.

Macrobenthic Community Structure and Water Quality Evaluation in Ulungu River Basin (Northwest China)

In this study, the composition and structure of the macrobenthic community in the Ulungu River Basin was investigated and the water quality status of the basin was evaluated. In May and August 2022, and October 2023, the macrobenthic and water environmental factors at 11 sample sites in the basin were investigated, and the water quality of the basin was evaluated by the Shannon–Wiener index, FBI, and BMWP index. A total of 6101 macrobenthic organisms were collected; these organisms belonged to 3 phyla, 7 classes, 14 orders, 57 families, and 117 genera. Arthropod species accounted for the largest number of species (87.9%). A total of nine dominant species were found: Micronecta sp., Eukiefferiella sp., Baetis sp., Polypedilum sp., Saetheria sp., Ephemerella sp., Limnodrilus sp., Ephemera sp., and Hydropsyche sp. At the temporal level, the average density and biomass of macrobenthos were in the order of August > October > May; at the spatial level, the average density was greater in the tributaries than in the main stream, and the average biomass was greater in the main stream than in the tributaries. The mean values of the Shannon—Wiener index and Margalef richness index were as follows: August > October > May at the temporal level; the mean values of the Pielou evenness index were as follows: May > October > August at the temporal level. At the spatial level, the overall mean value of each diversity index indicated that the tributaries had larger diversity indices than the main stream. The water quality evaluation results revealed that the overall water quality level of the Ulungu River Basin ranges from light pollution to poor quality. Human interference activities greatly impact the water quality of the basin. To restore the ecology of the basin, it is necessary to strengthen the management and control of pollution sources.

Evaluación de la calidad del agua mediante el uso de macroinvertebrados como bioindicadores en el Río Toribio de Ciénaga – Magdalena

Water quality in various aquatic ecosystems has become very important nowadays due to the effects of anthropogenic impact, which is why developed countries have made managements plans for these ecosystems based mostly on the use of physicochemical indices that provide instantaneous data on the state of the resource and, according to these indices, establish regulations on the management of this resource. Therefore, at present the use of bioindicators has become very relevant when evaluating aquatic ecosystems, since they can evaluate not only the quality in physicochemical terms but also the ecological quality of the entire ecosystem. In this sense, the research aimed to evaluate the water quality of the Toribio River using macroinvertebrates as bioindicators, applying the BMWP -Biological Monitoring Working Party- biological index. The study was descriptive since physicochemical data and the different populations of macroinvertebrates present in three stations established in the lower area of the Toribio River were collected in two rainy seasons of the year: one rainy and the other dry. For this, specimen capture, identification and taxonomic classification were carried out to later apply the BMWP index, in order to establish the ecological quality of the ecosystem. Among the data obtained from the sampling, one of the most notable is the difference in macroinvertebrates present in the two seasons studied (dry season and rainy seasons) and how these conditions affect the presence or absence of these species.

Health Assessment of the Stream Ecosystem in Beijing, China

With economic development, the health of river ecosystems is becoming severely threatened because of the increasing effects of human activities on river ecosystems. Here, 101 sites along regional river systems in Beijing rivers were investigated from autumn 2020 to summer 2021. A total of 34 metrics, including aquatic organisms, hydrology, water quality, and habitat, were calculated to be the candidate indicators. Principal component and correlation analyses were used to select the core metrics from the candidate indicators, and the weight of each core metric was estimated using the entropy method. The integrated index of stream ecological health was constructed to assess the health condition of the Beijing rivers. The results of the PCA and correlation analyses revealed that eleven metrics were selected as the core metrics to construct the integrated index of stream ecological health, including water temperature, flow velocity, BOD5, NH4+-N, Cu, the density of phytoplankton and zooplankton, the Shannon-Wiener diversity index of macroinvertebrates and fish, the BMWP index, and the qualitative habitat evaluation index. According to the health assessment results, 4.95% of the sampling sites were healthy, 23.76% were subhealthy, and 71.29% were in a fair or below healthy state. The river health status showed strong spatial heterogeneity, and the river health statuses in the northern and western regions were relatively good, whereas the river health status in the central and southeastern regions were relatively poor. The results of four aspects stream ecosystem assessment showed that the overall water quality of the rivers was "subhealthy" and the aquatic organisms and habitat were "general poor," but the hydrology was "poor." The evaluation results of five water systems demonstrated that the Chaobai River had the best health status, followed by that of the Yongding River, Daqing River, and Jiyun River, and the Beiyun River had the worst health status. Maintaining river ecological baseflow, ensuring river system connectivity, and improving and restoring the river habitat environment are the key aspects of river ecological restoration and protection in Beijing in the future.

Integral Index of Water Quality: A New Methodological Proposal for Surface Waters

A methodology is proposed aimed at defining an integral index of water quality in surface waters that incorporates the information for five variables currently used to independently measure the condition of water in the Cupatítzio River, Michoacán. The variables considered were the current water quality index used by CONAGUA, the concentration of metals, biodiversity as assessed through the BMWP index, microbiological values for Escherichia coli, and the level of toxicity. The index was applied at 17 sites along the Cupatitzio riverbed in the dry season of 2017. Each variable was assigned a rank, which was standardized to a scale of 1–10 and subsequently multiplied by a weight (W) that numerically represented the degree of importance and influence that each factor had in terms of pollution. These factors depended on the anthropic condition of the area, with a value of 5 indicating the method with the most significant impact and 1 the least. The integral index of water quality (IIWQ) was calculated as the arithmetic sum of each factor considered, generating a single value. It had intervals of 15 points minimum to 150 maximum. Five water quality levels were proposed: excellent, good, fair, bad, and very bad. The results showed that, of the 17 sites studied, the majority (ten) were in the fair quality category, ranging from 69 to 95 points; six were in the good category (96 to 122 points); and only one was in the bad category (42–68 points). With the application of this methodology incorporating the information for the five variables already described, it was possible to assess the water quality conditions in the Cupatitzio River as adequate and the water as suitable for its uses in the different socioeconomic activities for which it is destined.

Biomonitoring as a tool in assessing the water quality of Ghodha Pachad Dam (district Bhopal, M.P.) during summer season

Macrozoobenthos comprise an important group of aqua fauna by way of their contribution to ecosystem stability, besides acting as potential bio indicators of trophic status. Numerous plants and animals that have benthic aquatic and terrestrial components-which are essential for life-find habitat in rivers. The Ghodha Pachad Dam, which is found in the Bhopal district's Huzur tehsil, was the subject of the current study. Rainwater is the primary source of water for this dam. In this investigation, two sampling locations were used. To determine the Ghodha Pachad Dam's level of contamination, samples were taken and examined. The study's objective was to evaluate the water quality using Macrozoobenthos. Utilizing the BMWP and ASPT Scoring Index as well as physicochemical characteristics recommended by APHA, the water quality was evaluated. A total of 21 species of macrozoobenthos were observed in Ghodha Pachad Dam belonging to three phyla viz., phylum Arthropoda, phylum Mollusca and phylum Annelida BMWP and ASPT scores, combined with biological and physico-chemical characteristics of the water, can be used to correlate the level of contamination at the dam.

Monitoring and assessment of anthropogenic impacts on water quality by estimating the BMWP and ASPT indices for a headwater stream in Doon Valley, India

Monitoring and assessment of anthropogenic impacts on water quality by estimating the BMWP and ASPT indices for a headwater stream in Doon Valley, India

Aquatic macroinvertebrates as bioindicators of the harvest effect on mountain streams afforested with exotic pines

Land use change is one of the main factors affecting stream ecosystems since it modifies aquatic-terrestrial linkages and then structure and functioning as well. The aim of this study was to evaluate the effect of harvest on mountain afforested streams (Córdoba, Argentina). We explored the macroinvertebrate community changes after harvest and applied biotic and multimetric indices using natural grassland streams as a reference condition. Physicochemical variables were measured and benthic invertebrate samples were collected in three streams draining grasslands (reference streams) and three contiguous streams draining plantations of Pinus elliottii over four years (2008, 2012, 2014 and 2015). Some afforested streams were harvested in 2012 and the others onwards. Assemblages did not differ between grassland and afforested stream, according to the results of the multivariate analysis. Richness and diversity were higher in grassland streams than in the afforested ones, without distinction among pre and post-harvest conditions. The multimetric indices and BMWP index, confirmed some degree of deterioration in afforested and harvested streams. Our findings may constitute a valuable tool for the development of management strategies that attempt to preserve the ecological integrity of stream systems in forestry environments.

Assessment of the ecological state of small rivers of St. Petersburg according to the benthic macroinvertebrates indicators in 2019-2021

The work is devoted to the topical issue of assessing the state and changes of river ecosystems located within the boundaries of large cities and industrial agglomerations. The paper presents the results obtained during hydrobiological studies on small rivers of St. Petersburg (Russian Federation) in 2019-2021. The application of bioindication methods is substantiated in order to assess long-term changes in aquatic ecosystems under conditions of increasing anthropogenic load. Various characteristics of the community of benthic invertebrates are used as biological indicators of the state of hydroecosystems. Benthos samples were taken on eight small watercourses of the city, which are both tributaries of the Neva River of various orders (the Okhta, Slavyanka, Chernaya Rechka, Lubya, Okkervil, Volkovka rivers) and delta watercourses (the Smolenka and Karpovka rivers). The paper provides a brief description of the studied water bodies and sampling sites. A number of biotic metrics and biotic indices used for bioindication purposes both in Russia and abroad have been identified. It is noted that the unstable hydrochemical regime and low flow velocity in the small watercourses of the Neva River delta contribute to the intensification of the accumulation of sediments with high concentrations of ecotoxicants, which negatively affects both quantitative and qualitative characteristics of biocenoses. In some watercourses re is a complete absence of bottom invertebrates, which can be assessed as an ecological disaster. When assessing water quality by quantitative and qualitative characteristics of communities of benthic invertebrates (Mayer index, BMWP index, some biotic metrics), it can be concluded that Okkervil River, Chernaya Rechka River and Volkovka River should be attributed to watercourses whose ecological state is extremely unfavorable. The ecological state of the rivers Karpovka River, Slavyanka River, as well as the estuaries of Okhta River and Smolenka River should be considered unfavorable. And finally, the situation in Lubya River, the source of Smolenka River and in the middle reaches of the Okhta River can be considered close to satisfactory (low quality according to BMWP or moderately polluted water according to IM).

Spatio-temporal variation of hydrobiological communities (Animalia: Invertebrata) downstream of the El Quimbo dam, Huila, Colombia

Objective: To analyze preliminarily the hydrobiological communities of macroinvertebrates downstream of the El Quimbo dam, Huila, Colombia, to establish possible changes from the dam construction date to the second year of commissioning, in a period of seven years of samplings (2011-2017). Scope: To establish possible changes in space-time based on the analysis of diversity parameters and the BMWP and ASPT index. Methodology: Aquaticinvertebrates were collected during seven years at six sampling stations using Surber traps in 10 sites along 100 m; the specimens were preserved in ethanol 70%. The diversity parameters (abundance, richness of species, density and Hill numbers) and the BMWP and ASTP indexes were analyzed throughout the sampling period to relate them to some environmental factors. Main results: 36,490 specimens that belong to 11 classes, 26 orders, 79 families and 168 taxa were analyzed. Decreases in the BMWP/Col and ASTP indices were observed in the MGE1, MGE2 and MGE3 sampling stations, during the first phases of the project. Abundance increased significantly in mid 2013, during the river diversion stage, as well as during the operation years, while richness of species and potential richness of species increased at the beginning of 2012, 2015 and 2017, possibly synchronizing with the start of the rainy season. Conclusions: Reductions in the biodiversity indices and parameters were observed in the MGE1, MGE2 and MGE3 stations, in the river diversion and filling phases, which normalized towards the second year of operation of the dam.

AVALIAÇÃO DOS PARÂMETROS FÍSICO-QUÍMICOS E BIOLÓGICOS DAS ÁGUAS DO CÓRREGO DA CASCATA

The hydrographic basins have been going through several transformations of their natural landscapes through anthropic interventions, which causes environmental disturbances in the water bodies. The Córrego da Cascata basin has the largest Atlantic Forest forest fragment in the municipality of Presidente Prudente – SP, it is in a scenario of landscape transformation through land use and land cover due to the increase in human activities such as urbanization, pasture for pastoral, perennial and annual agriculture. The aim of this study was to evaluate the physical-chemical and biological parameters of the waters of the stream, which crosses the Chico Mendes Municipal Ecological Park (Mata do Furquim). According to the IQA, the three study points were classified as regular along the stream. The BMWP index rated one point as bad and two points as regular waters.

Karasu Deresi’nin (Karadeniz) bentik makroomurgasız çeşitliliği ve su kalitesi

The study was conducted in Karasu Stream (Sinop Province, Black Sea Region of Turkey). The purpose of this study is, to determine the benthic macroinvertebrate composition of the stream, together with some of its environmental characteristics (water temperature, pH and dissolved oxygen) to evaluate the trophic level of the stream. Samplings of benthic macroinvertebrates and environmental variables were performed monthly at ten stations between February 2013 and January 2014. As a result, 18260 specimens were investigated and 175 taxa were determined. Chironomidae and Oligochaeta were the higher groups in terms of species richness with 48 and 38 taxa, respectively. The BMWP and ASPT indices indicate that all the stations belong to “slightly polluted (Class II)” or “unpolluted (Class I)” water quality levels.

Impact of urbanization on the water quality of the Uberaba River and tributaries

This paper evaluated the quality of the water in Uberaba River and tributaries. Seven sites were sampled, in a 12-km under the influence of the urban area. The sampling site started upstream the raw-water catchment station, passing through the urban perimeter, upstream and downstream the discharge of the effluent treated by the Sewage Treatment Plant. Benthic macroinvertebrates were collected using a Surber net and, after identification, the indices of BMWP, diversity, equitability and dominance were calculated, besides functional group analysis. In each sampling site, it was analyzed microbiological and physicochemical parameters in order to identify possible domestic and/or industrial pollution sources. A rapid assessment protocol (RAP) was also applied, and land use and occupation aspects were mapped. The water collected in the furthest sampling site from the urban area and with vegetation in the surroundings, presented satisfactory quality, based in BMWP index. However, this quality dropped to very poor as the river water crossed the urban perimeter. The land use and occupation map showed a predominance of agriculture/pasture and urbanization. In addition, the presence of E. coli and the high levels recorded for some metals (principally cooper and cadmium), suggested contamination of the water with domestic and industrial effluents.

Evaluation of the impact of heterogeneous environmental pollutants on benthic macroinvertebrates and water quality by long-term monitoring of the buyuk menderes river basin.

Biomonitoring is a significant method for evaluating aquatic life forms and their environments. The longer the process continues, the results of it become more precise. Benthic macroinvertebrates' exposure to changes in environmental conditions makes them an important part of any biomonitoring program. This paper reviews a long-term water quality of the Buyuk Menderes River Basin which is the biggest river basin spread across the western Anatolia (Turkey). The study area was divided into three regions (Usak, Aydin, Denizli), primarily considering the provincial borders in the basin. A total of 40 sampling sites from the main river and its tributaries were selected. The prominent agricultural and industrial pollutants (textile, tannery and sugar factories) from each region have been taken into account. The most common and current biotic indices (BMWP Spanish version, ASPT, RBPIII, MMIF, EPT%, Diversity and Evenness) based on the pollution tolerance of benthic macroinvertebrates have been used to track water quality changes. The relationships between environmental variables (sO2, dO2, water temp., salinity, flow, TDS, Cond, pH, NO3-N, NO2-N, PO4-P, Fe+3, NH4-N) and bioindicators have been revealed by using multivariate analyses (NMDS, CCA). The region-based variations in water quality were compared with the Kruskal-Wallis test. The one-way variance analysis test (ANOVA) was used for the contrast between the biotic indices. Significant differences (p<0.05) were found among the regions in terms of Shannon-Wiener, Evenness, BMWP and MMIF indices. Regions were separated according to pollution sources, and the impact of provinces on water quality may vary according to their industry types. It has been observed that pollutants can spread across a basin for very long distances and reinstatement of the environmental conditions may require long periods.

ЗООБЕНТОС ВОДОТОКОВ БАССЕЙНА РЕКИ БУХТАРМА (ВЕРХНИЙ ИРТЫШ, ЮГО-ЗАПАДНЫЙ АЛТАЙ) НА РЕФЕРЕНТНЫХ УЧАСТКАХ И В ИМПАКТНОЙ ЗОНЕ

The composition, structure, and spatial distribution of zoobenthos in streams of the Bukhtarma River basin are described and quantitative indicators of benthos in the lower course of the Bukhtarma River are given. The predominance of insects from the orders of mayflies, caddisflies, and freckles is characteristic of the water-courses in the Bukhtarma River basin and is associated with the presence of stony soils in the rivers, rapid flow, moderate-cold-water temperature regime, and high oxygen content in the water – factors that are most favorable for these groups of invertebrates. To assess the ecological state of surface waters in the streams under study by bioindication methods, TBI, BMWP, ASPT, and ERT biotic indices are used. The taxonomic composition of each of the studied watercourses and river sections is formed in accordance with specific environmental conditions associated with natural and anthropogenic factors. It is established that watercourses in the reference areas can be used as reference ones in accordance with the requirements of the EU Framework Water Directive, and the characteristics of invariant States of biocenoses of the lower course of the Bukhtarma River in the impact zone are also given using the criteria of the V. A. Abakumov system of ecological modulations.

Изучение сообщества макрозообентоса и оценка экологического состояния р. Тандзут для улучшения системы гидробиологического мониторинга в Армении

The improvement of water management calls for action in the Republic of Armenia. Nowadays, the development of the hydrobiological monitoring approaches and procedures is the main goal. However, a lack of knowledge on the background conditions prevents further activities of revaluating of the methods used for water monitoring in Armenia with the EU WFD principles. Following the results of baseline studies conducted in the Debed River system, it was concluded to investigate small tributaries in order to find the most relevant and the best available site in the drainage basin. The study aims to analyse the community of benthic macroinvertebrates of the Tandzut River. We suggest the Tandzut River as a relevant substitution for the recent best available site in the area due to the ecological status of the upper reaches of the Tandzut River, which is by one category higher than the recent best available site of the Pambak River system according to BMWP index.

Aquatic macroinvertebrates (Animalia: Invertebrata) of the area of influence of El Quimbo Hydroelectric Station, Huila, Colombia

Objective. To carry out an analysis of the hydrobiological communities of macroinvertebrates of the discharge flows of El Quimbo hydroelectric plant, Huila, Colombia. Scope. To make a contribution to knowledge about the aquatic macroinvertebrate species in the upper basin of the Magdalena river. Methodology. Aquatic invertebrates were collected at six sampling stations using Surber traps at 10 sites along a 100 m linear transect. Main results. A total of 36,490 specimens belonging to 11 classes, 26 orders, 79 families and 168 taxa were collected. The class Insecta presented the highest values with nine orders (34.62%), 55 families (69.62%) and 137 taxa (81.55%). The assessment of the water quality in the study area showed that all the stations have good waters quality for the BMWP index, and all the stations have questionable water quality for the ASPT index. The analysis of similarity between the sampling stations found great similarity between all the sampling stations, except MGE4. possibly due to the influence of the treated wastewater that falls into the river a few meters upstream. Conclusions. This document makes a significant contribution to the knowledge of the aquatic macroinvertebrate communities for the study area. However, it is known, that the different phases of the hydroelectric project affect these communities in different degrees, which will be the subject in future studies.

Physicochemical and biological status of Aghlagan river, Iran: effects of seasonal changes and point source pollution.

Although the macroinvertebrates have been widely used as bio-indicator for river water quality assessment in developed countries, its application is new in Iran and data on the health status of the most ecologically important rivers in Iran is scarce. The present study aimed at monitoring and assessing the ecological quality of Aghlagan river, northwest of Iran, using integrated physicochemical-biological approaches. A total of 14,423 samplings were carried out from the headwater to downstream sites at four stations (S1, 2, 3, 4) by a Surber sampler (30 cm × 30 cm) from June 2018 to April 2019. The results obtained from macroinvertebrate biotic index revealed that the genera of Gammarus (Amphipoda) and Baetis (Ephemeroptera) were the most abundant in all seasons. The PAST software was applied to analyze the diversity indices (Shannon-Weiner diversity, Evenness, and Simpson indices). Based on the cluster analysis, S3 established the least similarity to other stations. The average frequency of each macroinvertebrate species was determined by one-factor analysis of similarities (ANOSIM). In accordance with canonical correspondence analysis (CCA), temperature and phosphate were found as the dominant factors effecting the macroinvertebrate assemblage and distribution. Moreover, the results obtained from the biological indices concluded very good quality of S4 by Helsinhoff and EPT indices and fair quality using BMWP index. The data on the macrobenthos assemblage and dynamics in the Aghlagan river across a hydraulic gradient provided useful information on water management efforts that assist us to find sustainable solutions for the enhanced quality of the river by balancing environmental and human values.

Lentic chironomid performance in species-based bioassessment proving: High-level taxonomy is not a dead end in monitoring

Chironomid identification for freshwater bioassessment purposes is rarely finer than family or subfamily level. This has led to their taxonomic neglect and a lack of knowledge about their characteristics and ecology at the genus or species level, which in turn makes their implementation in bioassessment models even less appealing. The aim of this study was to object against this practice and evaluate the possibility of using chironomid assemblages solely in assessing organic and nutrient enrichment levels of lentic habitats. For this purpose, the littoral zone of 28 lentic water bodies of the Dinaric western Balkan ecoregion was sampled. Due to the scarcity of natural lakes in this region, resulting from its specific karst geology, both natural and artificial water bodies were included in this survey. Chironomids, determined mostly to species and genus level, were tested in response to variables associated with organic enrichment (dissolved organic carbon and oxygen demand measures) and nitrate concentration. A metric (Lake chironomid metric, LCM) based on 107 chironomid taxa was developed and proven to reflect organic enrichment more precisely than standard metrics that respond to organic enrichment (BMWP and different Saprobic indices). We found that the LCM strongly supports the use of chironomids with high taxonomic resolution in lentic habitat assessment, as we have shown that chironomids have the ability to improve, or even replace, already existing models for organic nutrient enrichment. We have also shown that chironomids can be used in assessing even finer levels of nitrate pollution with changes in community occurring at as low as 0.07 mgNO3−/l. This allows earlier intervention and hopefully prevention of considerable damage to the environment. We can conclude that chironomids (especially determined to species level) have great potential in monitoring of lake ecosystems.