Bioindicators Of Quality Research Articles

Caatinga Microbiome Initiative: disentangling the soil microbiome across areas under desertification and restoration in the Brazilian drylands

The Caatinga biome in Brazil is renowned for its rich aboveground biodiversity. However, approximately 19% of this biome has experienced desertification, severely affecting the soil microbiome. Monitoring these microbial communities is essential to understanding the impacts of desertification and the potential outcomes of restoration efforts. The Caatinga Microbiome Initiative aims to assess the soil microbiome in areas undergoing desertification and those under restoration in the Brazilian drylands. This initiative seeks to explore the core microbial communities and their functions, including overlooked groups such as protists, nematodes, and viruses across native, desertified, and restored areas. We believe that two approaches should be used simultaneously in the study of microbiomes in areas undergoing desertification. First, the use of the soil microbiome as a bioindicator of soil quality in both desertified and restored lands. Second, the manipulation of the microbiome to facilitate soil restoration. By understanding soil microbiome responses to desertification and restoration, we can develop targeted restoration strategies to enhance biodiversity and promote functional recovery in desertified areas.

Identification of Benthic Foraminifera Presence in The Marginal Environments of Biliran Island, Philippines.

Benthic foraminifera are unicellular marine micro-organism with a hard exoskeleton and commonly present in the benthic community of marine ecosystem. This study aimed to identify the benthic foraminifera present along the coastal areas of eight municipalities in Biliran Island, Philippines. Quadrat sampling was conducted and three samples per quadrant transect of 1 m × 1 m divided into nine squares were collected. The samples were then observed under the microscope, and the specimens seen were identified by comparing them with the images of the sample species from the website https://marinespecies.org/. The researchers conducted an in-situ collection of the foraminiferal shells from intertidal areas along shallow water coastlines of the island. Results showed that the coastal environment of Biliran Island has the presence of the genera Spirillina, Quinqueloculina, Marginopora and Sorites. The identified species were classified based on their feeding mechanisms as herbivory and passive suspension feeding. The presence of benthic foraminifera species along the coastal environments of Biliran Island provides a record of the environment where they are found, making them natural bioindicators of water quality. This study provides a baseline for further studies on the distribution and abundance of benthic foraminifera in the area and can contribute to the understanding of the environmental conditions of the coastal areas in Biliran Island.

Benthic Macroinvertebrates as Bioindicators of Water Quality in the Vilcanota River, Cusco-Peru

Benthic Macroinvertebrates as Bioindicators of Water Quality in the Vilcanota River, Cusco-Peru

Snakes as sentinel of zoonotic yeasts and bio-indicators of environmental quality.

Reptiles in the wild or as pets may act as spreaders of bacteria, viruses, fungi and parasites. However, studies on the mycobiota of these animals are scanty. This study investigates the occurrence of yeasts from the cloacal swabs of snakes of different origins and the antifungal profile of the isolated strains. A total of 180 cloacal samples of snakes were collected from Morocco (Group I: n = 68) and Italy (Group II: n = 112). Yeast species were biochemically and molecularly identified. A total of 72 yeast strains belonging to 13 genera, 8 from snakes in Group I and five from snakes in Group II were identified. The most frequently isolated species were Trichosporon asahii (22.2%) and Candida tropicalis (15.3%) from snakes in Group I and Debaryomyces spp. (16.7%) and Metahyphopichia silvanorum (11.1%) from snakes in Group II. Multiple azole and amphotericin B (AmB) resistance phenomena were detected among isolated yeasts. Azole multi drug resistance phenomena were detected among yeasts from Group I and Rhodotorula mucilaginosa from Group II, whereas AmB resistance phenomena among those from Group II. Data suggest that snakes may harbor pathogenetic yeasts, being potential reservoirs and spreaders of these organisms in the environment. Since the yeast species community from different groups of animals as well as their antifungal profile reflects the epidemiology of human yeast infections in the same geographical areas, the results indicate that snakes may be considered as sentinels for human/animal pathogenic microorganisms and bio-indicators of environmental quality.

Literatur review : protozoa parasit di air sungai

River water is potentially unsafe and polluted, which can cause serious infections. Waterborne infections are a major cause of global mortality and morbidity. In cases of diarrhea, this research aims to identify the types of parasitic protozoa and their distribution in waterways in Japan and Indonesia. This research reviews literature by collecting data from various sources, such as books, national and international scientific journals. The articles analyzed are original articles relating to protozoa in river water from both countries. In Japan, protozoa such as Henneguya were found in the Omoi River and Cryptosporidium parvum in several rivers in Hokkaido. In Indonesia, species such as Codonellopsis sp., Favella sp., Tintinnopsis sp., and Codonella sp. are found. in Sorong Regency, as well as various other types in West Bandung, Central Sulawesi and South Kalimantan. The diversity and distribution of protozoa is influenced by water quality, physical conditions, water chemistry, and human activities. This research can provide information regarding protozoa which can act as bioindicators of water quality. The presence and diversity of protozoa can provide an indication of the health condition of aquatic ecosystems. As a result, conservation efforts and management of aquatic ecosystems can be improved.

Diversity of Fish Species as Bioindicators of Water Quality in The Cikapundung River, Bandung City

Human activity along the river impacts the aquatic environment from biotic and abiotic factors. One indicator that can reflect the quality of the waters is fish diversity. Several studies have used fish diversity as a biological indicator to determine the quality of waters, such as lake and river waters. The purpose of this study was to determine the diversity of fish and also to determine the quality of water in the Cikapundung River, Bandung City. The method used in this study was a survey and exploration method, which involved collecting samples at five stations using umbrella traps, cast nets, and fishing gear in the morning and evening. The fish obtained were identified using the Fish Identification Guidebook, and the number of each type was calculated. The biotic data obtained were processed using the Shannon-Weiner diversity index (H'), Evenness index (E), Margalef Abundance index (Dmg), and Simpson Dominance index (C). In contrast, the abiotic data were sent to the water quality testing institution (LPKL). The study's results identified seven species from 5 families: Cyprinus sp., Ancistrus sp., Xiphophorus sp., Barbodes sp. According to the Shannon-Weiner index, the diversity of fish species in the Cikapundung River in Bandung City is relatively moderate, with a value (H') of 1.55. The results of water quality measurements of the Cikapundung River from LPKL based on the class II water quality standards of PP RI Number 22 of 2021 show that the condition of the river is in the moderately polluted category.

The use of the micronucleus test and comet assay in wild rodents: a historical review and future perspectives.

Rodents are considered good models for investigating genotoxic damage and mutagenic alterations caused by xenobiotic agents, due to their occupation of a wide variety of habitats. However, relatively few in situ studies have focused on DNA damage in wild rodents associated with environmental exposure. In this review, we investigate trends in the application of the micronucleus test and comet assay in in situ studies of wild rodents. A total of 33 papers were identified, distributed across 14 different countries. Brazil and Spain had the most published studies (six each), followed by Bulgaria (n = 5), Mexico (n = 4) and Italy (n = 3). Only 24 of the 2,652 recognized rodent species have been the subject of in situ studies, which have most frequently focus on species of the genus Mus. The protocols used for the micronucleus test and comet assay varied widely, although blood and bone marrow were the primary types of tissue used. Given the paucity of studies on wild rodents, we recommend further research, particularly focusing on the use of this group as bioindicators of environmental quality and the standardization of protocols.

KEANEKARAGAMAN DAN KELIMPAHAN MESOFAUNA TANAH DI LAHAN BEKAS TAMBANG GAMPING KECAMATAN PADALARANG, BANDUNG BARAT

Soil fauna is one of the ecosystem components that play a role in the process of organic matter decomposition and soil improvement. Soil mesofauna are sensitive to environmental changes due to human activities, including land conversion for mining activities. The diversity and abundance of soil fauna depend on environmental conditions and food availability. Soil mesofauna can be used as bioindicators of habitat degradation and soil quality. This study aims to identify and assess soil mesofauna diversity index and abundance on open access land (LAT) formerly used for limestone mining in the Padalarang area, West Bandung Regency. Soil samples were collected from natural soil (844 masl), LAT 1 (837 masl), LAT 2 (834 masl), and LAT 3 (809 masl). Soil fauna were extracted using a Berlese Funnel Extractor. Soil fauna diversity was calculated based on Shannon’s Diversity Index, while soil fauna abundance was calculated based on Meyer's (1966) equation. The highest soil fauna diversity value was found in natural soil at 1.87 (moderate), while the lowest soil fauna diversity value was found in LAT 2 at 1.38 (low). The highest soil fauna abundance was found in LAT 2 (6295 individuals/m2) with a slope gradient of 8-15%, while the lowest abundance was found in natural soil (594 individuals/m2) with a slope gradient of 15-25%. Variation in abundance, taxon count, and soil fauna diversity is influenced by environmental factors such as soil pH, slope gradient, vegetation, and moisture content.

The alleviation of difenoconazole-induced kidney injury in common carp (Cyprinus carpio) by silybin: Involvement of inflammation, oxidative stress, and apoptosis

Triazole fungicides, such as difenoconazole (DFZ), are frequently used to control fungus in crops that pollute water. The common carp (Cyprinus carpio) (hereafter referred to as “carp”) is an excellent bio-indicator of water quality. The seeds of the silymarin plant contain a flavonolignan called silybin (SYB), which is used to treat liver disease. To explore SYB's involvement in DFZ-triggered kidney damage in carps, an H&E assay was conducted, and ROS level was also examined. The results demonstrated that SYB alleviated DFZ-induced destruction of kidney tissue structure in carps, as well as alleviating the elevation of kidney ROS level in carps. RT-qPCR and Western blot were used to detect inflammation-, oxidative stress- and apoptosis-related factors at mRNA level and protein level. The experimental findings indicated that relative to the DFZ group, SYB + DFZ co-treatment reduced inflammation-related mRNA level of il-6, il-1β and tnf-α, elevated mRNA level of il-10. It also reduced protein expression levels of NF-κB and iNOS. In addition, SYB + DFZ co-treatment reduced DFZ-induced increase in the oxidative stress-related mRNA indicators sod and cat, and decreased the protein expression levels of Nrf2 and NQO1. SYB reduced the DFZ-induced increase in pro-apoptotic gene Bax mRNA and protein expression levels and the DFZ-induced decrease in anti-apoptotic gene Bcl-2 mRNA and protein expression levels. In summary, SYB potentially mitigates DFZ-induced kidney damage in carp by addressing inflammation, oxidative stress, and apoptosis. Our results establish a theoretical foundation for the clinical advancement of freshwater carp feeds.

Zygoptera / Anisoptera (Insecta: Odonata) ratio as a tool to assess anthropogenic changes in Brazilian Cerrado streams.

Aquatic ecosystems are among the most affected by anthropogenic impacts, and the rapid detection and measurement of these impacts are of great importance for the maintenance of such environments. The order of aquatic insects Odonata has emerged as an important bioindicator of environmental quality due to its sensitivity to environmental changes and its ecophysiological requirements, which make them closely associated with habitat conditions. The aim of this study was to test whether the Zygoptera/Anisoptera ratio can be used as an effective tool to assess anthropogenic changes in Cerrado streams. Our hypothesis is that the proportion of Zygoptera/Anisoptera is an efficient tool for measuring environmental alterations in Cerrado streams, with a positive relationship between habitat integrity and the proportion of Zygoptera and an inverse relationship with the proportion of Anisoptera. Adults were collected in 44 streams of the Cerrado Biome in the eastern Maranhão state. The Habitat Integrity Index (HII) was used to verify the environmental gradient. Our hypothesis was corroborated, with a positive relationship between the richness and abundance of Zygoptera and HII, while an inverse relationship was observed for Anisoptera. According to our results, streams exhibiting a Zygoptera abundance of 68% or higher and richness of 58% or higher can be classified as preserved, while those showing an Anisoptera abundance and richness surpassing 31% and 41%, respectively, may be deemed altered. The patterns detected in the Cerrado were similar to those found in studies of the Amazon Biome and the Atlantic Forest, confirming the effectiveness of this method even for naturally open environments, such as the Cerrado. We conclude, therefore, that this method can be used as a tool to generate rapid results in monitoring studies, with low cost and easy application, enabling the development of mitigation, control, and conservation measures for extremely threatened environments such as those found in the Cerrado Biome.

ANTIMICROBIAL RESISTANCE PROFILE IN BROWN BOOBIES (Sula leucogaster) SAMPLES FROM STABILIZATION CENTER IN RIO DE JANEIRO, BRAZIL

Antibiotic-resistant bacteria pose a significant global health threat due to their widespread use not only in human medical settings but also in animal clinics and animal production, where they are employed for growth promotion and prophylaxis. The aquatic environment plays a crucial role in disseminating these resistant bacteria, with marine species serving as reservoirs. Seabirds, such as the brown booby, a coastal species, are effective bioindicators of environmental quality. This study aims to evaluate the resistance profiles of different antimicrobial agents in bacterial strains collected from brown booby samples treated at the stabilization unit in Riode Janeiro, Brazil, using the SIMBA platform. Samples from both live and deceased animals were collected for antibiogram testing. The most commonly identified species were Escherichia coli and Pseudomonas aeruginosa, primarily from the respiratory tract. The highest number of resistant isolates was observed in the β-lactams and fluoroquinolones classes. Medical significance was noted in the identified species and resistance genes, highlighting the impact of pollution on the environment and confirming the utility of brown boobies as bioindicators.

Macroinvertebrate Community as Bioindicator of Water Quality of Tambis River, Palompon, Leyte, Philippines

Macroinvertebrates have been used globally as bioindicators of water quality of rivers due to their varying tolerance to pollution. The water quality of Tambis River in Palompon, Leyte, Philippines was determined using macroinvertebrates and selected physico-chemical and ecological assessments. Employing kick-sampling method, three sampling stations were established based on the surrounding land use (forested, agricultural, and near residential). Twenty-seven macroinvertebrate families were identified. Permutational multivariate analysis of variance (PERMANOVA) revealed a significant difference in the benthic macroinvertebrate families across three stations (p=0.001). There was a decrease in the abundance of pollution-sensitive families from the forested station towards the downstream, closest to the residential area. Sensitive Ephemerellidae and tolerant Thiaridae were the most abundant in the forested and downstream area respectively. The highest diversity and evenness were observed from the agricultural area. Stream Invertebrate Grade Number - Average Level (SIGNAL 2) scores were plotted declined in all quadrants, suggesting good water quality to moderately polluted. Water temperature, pH, and velocity were the most influencing environmental variables to the macroinvertebrate assemblage as revealed by the Canonical Correspondence Analysis (CCA). Overall, the water quality of Tambis River ranged from being of good quality to moderately polluted. The data obtained in this study could serve as a baseline in providing information to formulate and implement scientific-based regulatory measures towards the conservation of Tambis River.

Keanekaragaman dan Status Konservasi Burung di Kawasan Gili Meno, Lombok Utara

The presence of birds in Gili Meno has a positive impact on environmental aspects as birds serve as bioindicators of environmental quality, pest controllers, and aid in pollination processes. Based on research conducted in 2010, 2011, 2012, and 2015, there has been an increase in bird populations in the Gili Meno area, particularly birds from the Ardeidae family. With rapid development currently underway, it is suspected to affect the presence of birds in Gili Meno, necessitating monitoring of bird diversity and conservation status in the area. This study aims to assess the diversity and conservation status of birds in the Gili Meno area. The research was conducted on Gili Meno from May to June 2022. Data collection utilized snowball sampling for interviews and transect methods combined with point counts. Observational data were analyzed using the Shannon-Wiener diversity index. The results indicate a total of 29 bird species found in the Gili Meno area, belonging to 22 families, with a diversity index of 2.8. The conservation status of most birds (97%) in the Gili Meno area is categorized as "least concern" according to IUCN criteria and classified as "unprotected" species under P.106/MENLHK/Setjen/Kum.1/12/2018. Acridotheres javanicus is listed as vulnerable by IUCN, while Thallaseus bergii is protected under P.106/MENLHK/Setjen/Kum.1/12/2018.

Arachnids: between fear and financial support for environmental education projects

Arachnids contribute to socioenvironmental development by acting as bioindicators of environmental quality and providing essential ecosystem services, highlighting the need for public awareness to conserve these potentially umbrella species. The aim is to evaluate the willingness to pay for informal education programs about arachnids in the central Brazilian savanna using the contingent valuation method (CVM). For this purpose, a preliminary analysis was conducted with 407 residents of a Brazilian municipality with a small population and significant incidents involving arachnid species. The respondents' profiles (gender, age, and education level), knowledge, perceptions of arachnids, and willingness to pay were collected. Quantification, average/total willingness to pay, and Pearson's correlation were performed using R software. Most respondents were women (75.43%), had a high school education and were aged between 35 and 65 years. We observed that most had some level of knowledge about the morphology, ecological characteristics, and importance of arachnids, especially for the environment. However, the results also indicate that older people, men, and those with lower education levels have a greater willingness to pay for educational events about Cerrado arachnids (IEPAs). Only a portion of the respondents were willing to pay for informal education programs in favor of arachnid awareness and conservation. The total willingness to pay was US$ 4,441.28, preferably managed by the state's public education institution. It is concluded that there is significant and necessary potential for environmental education actions to promote the conservation of arachnid megadiversity.

New insights on habitat use by larval Northern Emerald dragonflies (Somatochlora arctica)

Odonates are widely considered to be bioindicators of freshwater habitat quality. Somatochlora arctica (Corduliidae) is commonly found across Eurasia, predominantly in North and Central Europe, but in the UK, it has a restricted range and is listed as near threatened despite a large, potential habitat availability. Across their range, larvae are found in Sphagnum-filled bog pools near coniferous woodlands, but detailed data on their habitat requirements are limited and often overlooked in favour of adult surveys which inhibits conservation efforts. This study surveyed three areas across Scotland: Abernethy & Loch Garten National Nature Reserve (NNR), Beinn Eighe NNR and Flanders Moss NNR, to evaluate how different environmental factors per pool (e.g. water depth and chemistry, Sphagnum coverage, woodland distance, etc.) affect the presence of S. arctica larvae. We found a higher occurrence of S. arctica larvae when pools were located close to woodlands (i.e. 0–10 m), and had high coverage of Sphagnum (> 90%). Environmental variables in pools surveyed (i.e. conductivity, water depth, pH and water temperature) had no significant effects on S. arctica presence.Implications for insect conservation: Our results highlight and discuss the importance of nearby woodlands and Sphagnum cover for S. arctica larvae. Future conservation projects should consider the proximity of woodland to current and restored S. arctica sites or promoting expansion of surrounding natural woodland patches to benefit S. arctica and potentially other odonates sharing similar ecological preferences.

The Mesoamerican giant toad (<em>Rhinella horribilis</em>) as bioindicator of vegetation degradation in a tropical forest

Identifying species that can serve as bioindicators of environmental quality is essential for monitoring the anthropogenic impact. Common and widespread species can be ideal bioindicators due to their abundance and easy monitoring, but a confirmation of their differential responses as a function of habitat perturbation is needed. Because amphibians are known as good bioindicators of environmental perturbation, we conducted this work to identify whether a common, generalist amphibian species, the Mesoamerican giant toad (Rhinella horribilis), could serve as a bioindicator of environmental degradation in a tropical forest. We sampled toads in two areas of tropical forest that differed in anthropogenic degradation (primary vs. secondary forest), establishing in each of these areas two sections of the same surface area but differing in substrate (grass vs. sand). We analyzed toad abundance, sex ratio, body length and condition, and the amount and distribution across the body of ectoparasites (ticks). We analyzed 59 toads that were infested with 503 ticks. Based on a multi-model inference approach, the results suggested that toads were more abundant and had lower body condition in the secondary than in the primary forest. In the secondary forest, females were proportionally less abundant than males. The tick loads responded to an interaction of the body area with either the forest type or the substrate, with increased occurrence of ticks in toads from secondary forests and from grass sections. The differences found between the primary and secondary forests in sex ratio, toad abundance, body condition, and tick load across body regions are consistent with previous studies in other less common species of amphibians and thus posit R. horribilis as a good bioindicator of anthropic disturbance in this tropical forest.

Diversity of soil macrofauna in traditional oil mining of Wonocolo Geosite, Bojonegoro Geopark, East Java, Indonesia

Abstract. Rahmawati LA, Afiati N, Putranto TT. 2024. Diversity of soil macrofauna in traditional oil mining of Wonocolo Geosite, Bojonegoro Geopark, East Java, Indonesia. Biodiversitas 25: 2148-2160. Wonocolo traditional oil mining has been going on for 130 years and has led to soil pollution. This study aims to characterize the composition of macrofauna in the soil affected by Wonocolo's traditional oil mining. The existence of macrofauna is important as a bioindicator of soil quality and its role in maintaining soil fertility levels. Mining areas are grouped based on the density of the oil well (rare, medium and dense), then three sample points are selected in each group. Macrofauna were collected using quadrat-hand sorting, pitfall trap, and flannel trap methods, and then the community structure index was analyzed. The results showed that 709 individuals were collected consisting of 17 orders and 71 species, with 64.8% of individuals found in category-dense areas. Hymenoptera and Polyrhachis sp. as the most abundant order and genus, while Odontomachus brunneus Patton 1894 is the most frequently encountered species. The average value of biodiversity, dominance, and evenness index ranged H'=1.28-1.57 (low), C=0.29-0.38 (low), and E=0.78-0.90 (high), respectively. Indications of environmental conditions in traditional oil mining areas cannot be seen solely from the value of the macrofauna biodiversity index but are apparent in the abundance of the Hymenoptera order in all areas categories and significant presence of Polyrhachis sp. species in the dense category.

Macroinvertebrate Diversity as Bioindicator of Water Quality in Anggoeya River, Kendari City

Anthropogenic activities will affect the quality of river water and the living things in it, including macroinvertebrates. Anggoeya River is one of the rivers that water source is used as raw water for PDAM Kendari, so its quality needs to be considered. The purpose of this study was to analyze the water quality of Anggoeya River using macroinvertebrate bioindicators and the relationship between macroinvertebrates and physicochemical parameters of water and substrate of Anggoeya River. Physico-chemical parameters consist of temperature, current velocity, TSS, turbidity, pH, COD, BOD, DO, substrate pH, and substrate type. The sampling technique used purposive sampling, where macroinvertebrate sampling was carried out at three points at each station three times repetitions, namely on the left, middle, and right sides of the river, based on the type of river habitat, namely pool, riffle, and rapid. Top of Form The results obtained for the highest diversity value is at Station I with a value of 1.99 and the highest dominance value is at Station III with a value of 0.98. As for the best FBI value of the three stations, namely at Station II with a value of 5.43 with a moderate organic matter pollution category. For the results of physicochemical parameters, some of which do not meet or exceed the Quality Standards based on Government Regulation Number 22 of 2021, namely TSS at Station III, BOD at Station I and Station II, and DO at Station III. The results of the macroinvertebrate diversity index relationship with physicochemical parameters has a strong to very strong relationship.

Influence of storage method on the content of photosynthetic pigments of the aquatic moss Fontinalis antipyretica

Aquatic bryophytes are frequently used as bioindicators of water quality in rivers. Poor water quality increases physiological stress in moss, and stress levels can be estimated by measuring the concentrations of photosynthetic pigments and by calculating pigmentary indices. However, studies collecting many samples in a short time may need to store them until analysis. In the meantime, the pigments may suffer some degradation. Given the lack of studies on this problem for aquatic bryophytes, this one investigates the effect of three storage methods (refrigerated at 6 °C, frozen at − 20 °C and dried at room temperature) on the concentrations of chlorophyll a, chlorophyll b, pheophytin a and the following ratios: chlorophyll a/chlorophyll b, D430/D410, D665/D665a, D430/D665 and D480/D665 (where Dx is the absorbance at x nm) in the aquatic moss Fontinalis antipyretica. The results showed that refrigeration was the most suitable method, freezing might be suitable for some parameters, and drying was inadequate for this purpose. We recommend that all studies on photosynthetic pigments detail the time elapsed from collection to sample analysis, as well as the storage method used.

Aquatic insects as bioindicators of stream water quality - a seasonal analysis on Western Ghats river, Muthirapuzha, in central Kerala, India

This study was conducted to assess the water quality of Muthirapuzha River, Idukki using aquatic insects as bioindicators. Insects were collected on a seasonal basis from February 2014 to January 2015 from 12 sampling stations. Insects were sampled using standard collection methods and were identified up to family level. A total of 3,278 individuals belonging to seven orders and 37 families were collected during the study period. The greatest number of taxa was represented by order Ephemetroptera during monsoon (27%) and post-monsoon (25%), while Diptera (22.7%) dominated the pre-monsoon season. Shannon Weiner diversity index, Simpson dominance index, and Margalef’s richness index was highest post-monsoon. The EPT score in Muthirapuzha was for normal waters, however, pre-monsoon values were lowest, indicating pollution load during this period. Hilsenhoff’s family biotic index (HFBI) was used to estimate the status of organic pollution along the river based on representative families of aquatic entomofauna; values were highest at pre-monsoon season. The overall organic water quality level in the Muthirapuzha was good to fair based on this study.