Composition Of Macrozoobenthos Research Articles

Macrozoobentos Composition In The Babura River Sumatra Utara

To determine the composition of macrozoobenthos in the waters of the Babura river. The parameters measured are biological parameters, namely macrozoobenthos composition supported by physical and chemical parameters in the Babura river waters. The parameters measured in this research are biotic parameters, namely the type of macrozoobenthos and abiotic parameters, namely physical and chemical parameters. Physical parameters such as: temperature, turbidity, and chemical parameters such as: pH (degree of acidity), (DO), BOD, COD, and phosphate. Taking macrozoobenthos in shallow water using a quadrant and in deep water using an Eckman grab. Physical/chemical parameters are measured in situ and ex situ. Ex-situ is carried out in the BTKL laboratory. This type of research is ex-post de facto or only reveals existing data. Macrozoobenthos composition found in the Babura river: 1. There are six species of insects, namely Chironomus sp, Aeshna grandis, Dragonfiy nymph macronia, Agrion sp, Damsefly nymph, Dragonfly; 2. There are eight species of gastropods, namely: Thiara winteri, Thiara sp, Melanoides tuberculata, Melanoides rustica, Melanoides gramnifera, Brotia testudinaria, , Planorbis sp, Lymnaea rubiginosa; 3. There are two species of Hirudinea/Clitellata, namely Leeches and Glossiphoniidae; 4 There is one species of trematode, namely Pomatiopsis lapidaria Say; 5. There is one species of crustacean, namely Gammarus sp; 6. There is one species of nematode, namely the rolled worm; 7. There is one species of Oligochaeta, namely Tubifex sp; 8. There are three species of Turbilaria, namely Planaria sp, Dugesia sp, Mesostoma sp, so the macrozoobenthos composition consists of 8 classes with a total of 23 species. Physical/chemical parameters still support macrozoobenthos life in the waters of the Babura river.

Structure of the macrozoobenthos community in Buai River, Pulau Tengah, Keliling Danau District, Kerinci Regency, Jambi Province

Background: Buai River is a river located in the village of Jembatan Merah Pulau Tengah, Keliling Danau District, Kerinci Regency, Jambi. Sungai Buai with topographic conditions in the form of a hilly highland area, surrounded by mountains and dense forests so that it has a heterogeneous microhabitat and is still natural for macrozoobenthos. Therefore, a study was conducted on the presence and structure of macrozoobenthos in the Sungai Buai area of Central Island. This study aims to analyze the structure of the macrozoobenthos community based on the composition of the macrozoobenthos species, density, diversity, dominance and distribution of macrozoobenthos in the waters of the Buai River. This research is expected to provide information in the form of scientific data and knowledge about the structure of the macrozoobenthos community in the waters of the Buai River to be used as comparative data for future research. This research was conducted from January to February 2022. Method: The research method used is a quantitative descriptive method, which is to describe and evaluate a symptom or event that appears systematically. Determination of research stations is done by purposive sampling method, which is taken five stations based on environmental baseline. Data analysis was carried out by calculating the composition, macrozoobenthos density, Diversity Index, Dominance Index and Community Similarity Index between stations. Findings: The results showed that there were 5 classes, 11 orders, 26 families and 42 genera. Diversity values ranged from 1,4 to 2,45 which was classified as moderate, the dominance ranged from 0.1 to 0.45, and the similarity of the macrozoobenthic community in Sungai Buai 60.71% - 82.54% the similarity of the macrozoobenthos was relatively the same with little organic pollution. Conclusion: Based on the structure of the macrozoobenthos community in the Buai River, Central Island, it can be concluded that the Buai Pulau Tengah River, Keliling Danau District, Kerinci Regency, Jambi Province is still classified as very good. Novelty/Originality of this Study: This study presents novel findings by revealing the structure of the macrozoobenthos community in a relatively undisturbed highland river surrounded by dense forests, which provide a unique heterogeneous microhabitat. It contributes original data on the species composition, density, diversity, and distribution of macrozoobenthos in this specific region, offering a baseline for future comparative studies.

Factors of macrozoobenthos formation in low-mountain lakes of the Russian Altai

The current state of macrozoobenthos of six low-mountain lakes of the Russian Altai was studied in different hydrological seasons (May, July, September) 2022: Aya (Aiskoe), Beloe, Kireevo, Kolyvanskoe, Koksha, and Svetloe. The aim of the article is to study the factors of formation of benthic invertebrate communities of foothill lakes of the Russian Altai. In total 156 species from 9 classes of invertebrates were identified in the zoobenthos of the studied lakes, the highest percentage of occurrence was recorded for chironomids and oligochaetes. According to the taxonomic composition of macrozoobenthos, most of the studied lakes of the Russian Altai (Aya, Beloe, Kireevo and Kolyvanskoe) were close to flatland lakes. Two lakes (Koksha and Svetloe) combined characteristics of both flatland and highland lakes. The abundance and biomass of zoobenthos in lakes Aya and Kireevo corresponded to the oligotrophic level, in lakes Beloe and Kolyvanskoe to the mesotrophic level, and in lakes Koksha and Svetloye to the eutrophic level. The structural characteristics of macroinvertebrates are indicators of the state of lake ecosystems. Therefore, in order to maintain the health of lake ecosystems, it is important to determine the limiting factors for macroinvertebrate community composition and structure. The influence of environmental factors on the composition and structure of macrozoobenthos of foothill lakes of the Russian Altai was studied. The relationship of 10 main indicators of zoobenthos structure with 30 hydro physical and hydrochemical indicators was analyzed. Using principal component analysis, multiple regression method, correlation and canonical analyses, it was revealed that the greatest influence on the development of benthic invertebrate communities in the studied lakes of the Russian Altai was exerted by nutrients, permanganate oxidability and soil character and water temperature.

Distribution of Macrozoobenthos of Flowing Water Bodies by Altitudinal Belts of the Nakhchivan Autonomous Republic

Spatial distribution, species structure and ecological indicators of macrozoobenthos of flowing water bodies by altitude belts of Nakhchivan Autonomous Republic were studied. Macrobenthos fauna of the rivers of the region is formed in psammoreophilic, phytoreophilic and peloreophilic biocenoses with a great advantage of lithoreophilic biocenosis. The lithoreophilic biocenosis of rivers of the mountain and high-mountain belts is characterized by extensive area and abundance of species diversity. The core of the lithoreophilic biocenosis is composed of populations of rheophilic organisms such as moths, mayflies, vernal pools and simulids; its usual inhabitants are also rheophilic larvae of chironomids of the genus Polypedilum, Endochironomus, Eukiefferiella, Cricotopus and Orthocladius. The family composition of the fauna was found to be relatively stable along the rivers. Differences in the species composition of macrobenthos fauna, change of dominant species in biocenoses are related to biological features of the main species, anthropic and anthropogenic impacts, as well as different time of research. The species composition of macrozoobenthos of the rivers of the autonomous republic decreases from the source to the mouth.

Spatial and seasonal variation in macrozoobenthic density, biomass and community composition in a major tropical intertidal area, the Bijagós Archipelago, West-Africa.

The coastal intertidal ecosystem of the Bijagós Archipelago, Guinea-Bissau, one of the largest and most important in West Africa, sustains a considerable proportion of the migratory shorebird populations of the East Atlantic Flyway and operates as a nursery area for benthic fish in the region. The macrozoobenthos in these mudflats constitute the main food source for both groups so that spatial and temporal variation in their abundance and community composition is likely to influence the abundance and distribution of fish and birds. In this study we described the spatial and temporal dynamics in the density, biomass, and community composition of macrozoobenthos across six intertidal flats in three islands of the Bijagós Archipelago. Overall, the Bijagós Archipelago was characterised by a highly species-rich macrozoobenthic community, with ca. 88 taxa identified across all sites, reaching a mean density of 1871 ± 58.3 ind.m-2 (mean ± SE) and mean biomass of 5.65 ± 0.41 g of AFDM.m-2 (ash-free dry mass per m2), values much lower than what was described for nearby intertidal areas, namely the Band d'Arguin, Mauritania. Density and biomass of major macrozoobenthos classes (Bivalvia, Polychaeta, Malacostraca and Gastropoda) differed across sites and months, displaying an overall increase in density towards the final months of the dry season (March and April). Similarly, community composition also differed significantly between sites and throughout the season. The site with most distinct community composition (Adonga) supported low diversity and high abundance of a few bivalve species, whilst other two sites that hosted the most diverse communities, were also the most similar between them (Anrumai and Abu). These spatial and temporal patterns constitute an important baseline to improve knowledge of this intertidal ecosystem and will contribute towards a better understanding of the spatial and temporal distribution patterns of their consumers.

Habitat Degradation and Study of Macrozoobenthos Conditions in Homogeneous Mangrove Ecosystems

Habitat degradation that occurs in the mangrove ecosystem will have an impact on the presence of associated biota found in the ecosystem, including macrozoobenthos. If it continues, it will threaten the sustainability of macrozoobenthos resources which are characterized by decreasing abundance and it is not even impossible that one day they will become extinct. The purpose of this research is to analyze the species composition of macrozoobenthos and to analyze the composition of mangrove species. This research was conducted in the mangrove ecosystem of Naga Permai Beach, Gampong Lhok and Gampong Pulo, Kuala Pesisir District, Nagan Raya Regency, Aceh Province in December 2021. The research method was quadrat sampling. The results showed that the macrozoobenthos species found consisted of 2 phylum, 3 classes, 7 families with 16 species

Standing stock and composition of macrozoobenthos in the south-eastern Arabian Sea: A revisit after a decade

Changes in macrozoobenthic standing stock and composition along the south-eastern Arabian Sea continental shelf (30–200 m) are investigated, based on data collected from the same sites during the same season 14 years apart (winter monsoon, 1998 and 2012), using the same platform, sampling gear, methods etc. During both surveys, polychaetes dominated among the macrozoobenthos, followed by crustaceans and molluscs. A decline in macrozoobenthic density and biomass with increasing depth was noted in both surveys. Macrozoobenthic density increased significantly between 1998 and 2012, especially in the inner and mid shelf (30–50 m), due to the increase in density of polychaetes and molluscs, while the density of crustaceans decreased. The mean individual body weight of polychaetes decreased between 1998 and 2012, most notably in the inner and mid shelf (30–50 m). This reflected an overall increased dominance of small-sized opportunists such as spionids, magelonids, paraonids, cirratulids and pilargids in 2012 across the entire shelf. Such an increase in dominance of opportunists and decline in abundance of sensitive taxa is indicative of long-term environmental stress and anthropogenic pressure. However, no significant changes were noted in the measured environmental variables which are known to influence benthic faunal distribution in the region, such as sediment nature and oxygen availability. The observed changes may rather be indicative of the long-term effect of intense bottom trawling, which is practiced in the study area year-round. This is the first study of its kind for soft-sediment shelf benthos from the tropical belt.

Can artificial ecological islands alter the biodiversity of macroinvertebrate? A case study in Fujin National Wetland Park, the Sanjiang Plain, China.

Many policies and studies globally have highlighted the pivotal role of wetland ecosystems regarding wetland biota and their ecological status. With the strengthening of wetland ecosystem management legislation and policy, wetland restoration should also consider increasing habitat diversity to improve biota. We explore whether the construction of artificial ecological islands can increase the diversity of and macroinvertebrates before assessing the effects of actively constructing islands via human intervention on wetland protection.We discuss changes in macroinvertebrate diversity (i) with and without islands, (ii) at different water‐level gradients surrounding the islands, (ⅲ) on different island substrates, and (ⅳ) at different time scales. We used ANOVA, ANOSIM, and cluster analysis to test the differences.The macroinvertebrate communities had spatially heterogeneous distributions which changes over time due to both natural and anthropogenic stresses. The establishment of islands significantly increased the community composition and biodiversity of the macroinvertebrate. Water depth and substrate affect community composition of macrozoobenthos. The abundance and diversity of macroinvertebrates can influence the biodiversity of their predators (fish and waterbirds). Potentially, the construction of islands could provide some cobenefits for the conservation of wetland fauna. Synthesis and applications. Establishing artificial ecological islands in broad open‐water areas and increasing water‐level gradient and substrate diversity can increase microhabitat availability and habitat heterogeneity. These changes can adapt to different ecological niches of aquatic organisms, increase biodiversity, and have a positive effect on the ecological restoration of inland freshwater marshes and wetlands.

Benthic Community and Assessment of Water Quality Using Biological Index in RAMSAR, Ninh Binh

Van Long, the largest wetland RAMSAR in delta areas of northern Vietnam, is a famous destination for tourists, which might influence on water quality and biodiversity. Two surveys in September 2019 and May 2020 aimed to determine species composition of macrozoobenthos and build biological indicators to assess the water quality for biodiversity conservation. Present findings report a list of 41 species in 27 genera, 14 families of macrozoobenthos (Gastropoda, Bivalvia, Crustacea - Decapoda) in Van Long. Of which, Gastropoda is the most abundant, accounting for 58.5% of the total number of species, followed by Crustacean (26.8%) and Bivalvia (14.6%). Both Shannon-Weiner biodiversity (H') and Margalef indices “d” in rainy season are higher than those in dry season (H '= 2.565 vs. 2.466 and d = 4.987 vs. 3.286, respectively). For water quality assessment, based on TCVN 7220-2: 2002, the water in Van Long RAMSAR is in low level of pollution. According to ASPT index on average (3.42), this parameter was under medium to heavily polluted. The results recommend utilizing family taxon of macrozoobenthos with the recorded scales to assess quality of aquatic environments of freshwater bodies in northern Vietnam.

МАКРОБЕНТОС ОЗЕР ВОЖЕ И ЛАЧА

The taxonomic composition of macrozoobenthos in lakes Vozhe and Lacha and in some sections in the Svid and Onega rivers is presented. The dominant complex in the lakes was formed by representatives of chironomids. Two species of oligochaetes and a gastropod were dominant in the rivers. The index of faunal similarity of macrobenthos between the lakes was rather high and amounted to 70%, while the similarity between the river and lake benthos was less than 30%. In the lakes, only two taxonomic groups were recorded, oligochaetes and chironomids that formed the basis of the benthos abundance: 87–93% of the average abundance and 92–95% of the average biomass in the lake. Oligochaetes and mollusks played a significant role in the river communities; in total, they formed 76% of the total abundance and 98% of the biomass. The trophic structure of macrobenthos in the lakes was almost similar, except the appearance of the group of phytodetritophages- filter-feeders in Lake Lacha. Detritophages-swallowers dominated in the river communities. In the previous studies of the lakes, the species richness of benthos both in Lake Vozhe and Lake Lacha was much higher. A decrease in the number of taxonomic groups and decrease in their abundance were observed in Lake Vozhe. At the same time, the role of chironomids in the formation of benthos in the lake was still significant. In general, changes in the taxonomic structure and abundance of benthos in lakes Vozhe and Lacha may be caused by a complex effect of environmental factors and long-term and intra-annual dynamics of dominant (cenose-forming) representatives of the main groups of macrobenthos. The simplification of the structure of the bottom communities, the inclusion of species with wide ecological spectra, the predominance of eurybionts among the dominants, may indicate pollution, eutrophication, and contamination of water bodies. According to the indicator species both lakes may be regarded as mesosaprobic water bodies.

Macrozoobenthos in mid-mountain lakes of river Multa basin (Republic of Altai)

In August 2020, taxonomic composition and quantitative characteristics of zoobenthos from 4 lakes located in the upper reaches of the R. Multa basin (the R. Ob basin) were studied. Because of the basin inaccessibility the hydrobiological information about these lakes was previously fragmentary or absent at all. The data on macrozoobenthos composition and its structure were not available. In these lakes, 49 species of benthic invertebrates from 7 classes were identified, i.e. Demospongiae (1), Turbellaria (1), Oligochaeta (3), Gastropoda (4), Euchelicerata (1), Crustacea (1) and Insecta (38). Among insects, Diptera were the most diverse (22 chironomids out of 23 species). Beetles, mayflies and caddisflies were also found. In terms of species number, abundance and biomassб chironomids were the dominant taxonomic group in the studied lakes. The species composition of macrozoobenthos consisted of species widely spread in the Palearctic and Holarctic. The investigated lakes differed in species composition of zoobenthos. When comparing the species lists of benthic animals, lakes Sredneye Multinskoye and Poperechnoye were similar at most, whereas the fauna of Lake Nizhneye Multinskoye was the most original. The studied water bodies were distinguished by poor macroinvertebrate development and thereby corresponded to ultra-oligotrophic and oligotrophic reservoir types. The oligochaete index by Goodnight and Whitley corresponded to quality class I–II, i.e. “conditionally clean” and “slightly polluted waters”. We defined the trophic structure of macrozoobenthos of lakes and identified five main trophic groups of hydrobionts (Deposit feeders, Сollectors-detritus feeders and facultative filter feeders, Collectors-obligate filter feeders, Shredders, Predators), among which Collectors-detritus feeders and facultative filter feeders dominated.

МАКРОЗООБЕНТОС ЗАРОСЛЕЙ ВОДОРОСЛЕЙ CYSTOSEIRA CRINITA DUBY, 1830 У БЕРЕГОВ КРЫМА И КАВКАЗА (ЧЁРНОЕ МОРЕ)

The article provides summarized data of species composition, abundance, biomass, occurrence and trophic structure of invertebrate macrozoobenthos associated with red-book algae Сystoseira crinitа Duby, 1830 in the coastal waters of the Crimea (Cape Tarkhankut, Kruglaia Bay, Simeiz, «Cape Martyan» Reserve, Dvuyakornaya Bay) and the Caucasus (in the area of «Utrish Nature Reserve») in August-September 2012–2017 at the depth of 1, 3 and 5 m. A total of 46 samples were taken (42 quantitative and 4 qualitative). In the area of Utrish, such studies were carried out for the first time. In the algae communities of the Black Sea coast of Crimea and the Caucasus 56 species belonging to the types Annelida, Platyhelminthes, Mollusca and Arthropoda were identified. Ten species are common to all areas. The abundance and biomass near the Caucasus coast were 1432 ind. kg-1 and 9,52 g∙kg-1, near the coast of Crimea these values varied from 2506 to 6085 ind. kg-1 and from 23,9 to 43 g∙kg-1 respectively. Mollusks and crustaceans dominated in values of abundance, mollusks dominated in values of biomass. The highest quantitative indicators were recorded in the waters of Simeiz, the lowest – in the area of the «Utrish» Nature Reserve. Molluscs, in particular, Mytilaster lineatus Gmelin, 1791, make a significant contribution to the formation of macrozoobenthos abundance in the Simeiz area, while in the water area of Utrish the peaks of abundance have been defined due to crustaceans Ericthonius difformis M.-Edwards, 1830 and Ampithoe ramondi Audouin, 1826. Gastropods Rissoa splendida Eichwald, 1830, Bittium reticulatum (da Costa, 1778) and bivalve M. lineatus make the greatest contribution to the biomass of macrozoobenthos both in the waters of Simeiz and in the Utrish Reserve area. The high abundance and biomass of these molluscs allow them to form a macrozoobenthos nucleus in the studied water areas. Comparison of species composition of macrozoobenthos by the Chekanovsky-Sörensen community index showed high fauna similarity in all areas (the coefficient ranged from 0,4 to 0,76), as they are bound by the same biotope. The fauna of the Kruglaya Bay and Cape Tarkhankut are the most similar to each other. The areas in Dvuyakornaya Bay and Cape Martyan are the least similar to each other. The results of the cluster analysis confirm that the most similar areas in terms of presence/absence of species are Kruglaya Bay and Cape Tarkhankut, and also Dvuyakornaya Bay and Utrish area. The functional abundance index determined the communities of gastropod molluscs R. splendida (in the Tarkhankut, Simeiz and Utrish areas), B. reticulatum (in Kruglaya Bay) and bivalve M. lineatus (in Cape Martian and Dvuyakornaya Bay). It has been shown that the R. splendidа communities are more attracted to open coasts. In the R. splendida community from 16 to 25 species have been recorded in different areas, in the M. lineatus community in the water areas of the Cape Martian and Dvuyakornaya Bay (only quantitative samples were taken into calculation) 16 and 17 species were identified, in the B. reticulatum community – 25. In the majority of communities the guiding species were predominated. Their proportion was between from 32 to 56 % of the total number of species. Characteristic species dominate only near Utrish. Their share is 36 %. The number of rare species in communities varies from 3 to 9. The dominance-diversity curves indicate a more stable state of the epiphyton community in the water areas adjacent to the Utrish Reserve and Kruglaya Bay. Shannon index values also indicate high biodiversity in the studied water areas. The maximum Shannon Index value in terms of abundance was recorded in the B. reticulatum community (2,66) in Kruglaia Bay and a high value in terms of biomass (2,34) was marked in the R. splendida community in the Simeiz area. Five trophic groups have been identified. Phyto- and polyphages dominate by the number of species. Phyto- and sestonophages dominate in values of abundance, phytophages – in values of biomass.

ДОННАЯ ФАУНА НЕКОТОРЫХ ОЗЕР УЗБЕКИСТАНА

Species composition of macrozoobenthos of 6 lakes from different regions (north, center, south) of the republic have been studied. Total 111 species of bottom animals have been recorded. List of dominant species is presented. Using coefficient of Sörensen-Czekanowski similarity of species composition of macrozoobenthos of the lakes studied have been determined.

STUDY OF ECOSYSTEM OF THE SUKHUM BAY WITH EMPHASIS ANTHROPOGENIC IMPACT, ABKHAZIAN BLACK SEA COAST

For the first time in thirty years, baseline comprehensive studies plankton and zoobenthos of the Sukhum Bay were conducted and an assessment of its current environmental status was given. The summer phytoplankton abundance of the port of Sukhum was represented mainly by coccolithophorids Emiliania huxleyi and diatoms algae, among the latter, the common species in polluted or eutrophic brackish waters were recorded. The presence of euglenic algae and cyanobacteria indicates a higher nutrient status, pollution and desalination of the sea area. The alien species Peridinium quinquecorne Abé (Dinophyceae) was recorded in the Abkhazian coastal waters for the first time. Totally, 7 species of tintinnids belonging to 3 genera Favella, Tintinnopsis, Eutintinnus were established from the Sukhum Bay. Among them, the non-indigenous species Eutintinnus tubulosus and E. apertus were noticed. Tintinnid ciliates accounted for ca. 5% of total ciliates abundance. The values of the abundance of aloricated ciliates were comparable to the values obtained from offshore of bays and ports of the northeastern Black Sea. As the pressure of predators is reduced the well-pronounced peaks of holo- and meroplankton biomass were recorded in the last summer – early autumn. A significant part of total holoplankton biomass – 66.5 % (up to 1.1 g/m3) was composed of cladocerans Penilia avirostris. The meroplankton was dominated by larvae of bivalve mollusks Mytilaster lineatus, polychaetes Polydora cornuta and cirripede barnacle Amphibalanus improvisus. The number of meroplankton in the open Sukhum port was 10–15 times lower above than a level of values obtained for ports and bays of the northeastern Black Sea. Among ichthyoplankton, the dominant species were Mullus barbatus ponticus, Diplodus annularis, Trachurus mediterraneus, Engraulis encrasicholus and Sciena umbra. Mean abundance of ichthyoplankton in vertical catches was 5–10 times lower than in offshore of Anapa and Gelendzhik of the northeastern Black Sea. And the proportion of dead eggs was 2 – 3 times higher than areas of these resort cities. The composition of macrozoobenthos was drastically depleted and resembled that of the polluted port complexes of the northeastern Black Sea. Heteromastus association dominated in mud bottom sediments. Among spionid polychaetes, the worst invaders Streblospio gynobranchiata and Polydora cornuta have been recorded in soft bottom communities. Depletion of benthic communities, loss from the structure of the trophic web of the macrophyte community and appearance of cyanobacteria and a new alien species in the planktonic and benthic communities leads inevitably to imbalance of the structure of the Sukhum port ecosystem.

Effect of Zebra Mussel Dreissena polymorpha (Pallas, 1771) (Mollusca, Dreissenidae) and Perch Perca fluviatilis (L.) (Pisces, Perciidae) of Different Age Groups on the Structure and Main Characteristics of Macrozoobenthos in Experimental Mesocosms

The composition of macrozoobenthos in experimental mesocosms has been studied. A total of 116 invertebrate taxa are found, with chironomids (50 species), mollusks (25), and oligochaetes (21) the most widely represented. Most of the revealed taxa (61%) are common for Dreissena polymorpha (Pallas, 1771) biocenoses in the Rybinsk Reservoir; other species have invaded mesocosms during the experiment. The minimal number of invaders is found in mesocosms with perch larvae; the maximal is in both variants with the zebra mussel. It is shown that in the absence of zebra mussels those age groups of perch consuming macrozoobenthos reduce its main structural characteristics. The maximum sum of the main structural characteristics is recorded in mesocosms with yearlings of perch and zebra mussels. This indicates a positive environment-forming role of Dreissena polymorpha in benthic communities and the possibility that other invertebrates can use its druses as refuge.

Zmiinyi Island Coastal Zone Macrozoobenthos State in 2016-2017

Purpose. To study the state of macrozoobenthos in the Zmiinyi Island coastal zone in 2016-2017. Methods. Standard methods of macrozoobenthos sampling, determination, number and biomass estimation. Results. Results of analysis of biodiversity, structural characteristics and taxonomic composition of macrozoobenthos in the Zmiinyi Island coastal zone have been presented. Seasonal dynamics of its number and biomass has been studied. Assessment of marine environment quality has been performed based on the metrics of macrozoobenthos. Conclusions. Altogether, 132 taxa of benthic invertebrates belonging to 10 biggest taxonomic groups of macrozoobenthos have been identified in the Zmiinyi Island coastal zone in 2016-2017. Analysis of taxonomic composition identified 1 species of Porifera (0.8%), 7 taxa of Cnidaria (5.3%), 3 taxa of Platyhelminthes (2.3%), 1 taxon of Nemertea (0.8%), 3 taxa of Bryzoa (2.3%), 52 taxa of Annelida (39.4%), 25 taxa of Mollusca (18.9%), 35 taxa of Arthropoda (265%), 2 taxa of Echinodermata (1.4%) and 3 taxa of Chordata (2.3%). Out of 132 macrozoobenthos taxa 6 are enlisted in the Red Data Book of Ukraine and 8 – in the Black Sea Red Data Book. Macrozoobenthos number varied from 0.317х104 (27.11.2016) to 16.943х104 (19.08.2016) ind/m2 on soft substrate and from 2.683х104 (17.05.2016) to 30.725х104 (19.08.2016) ind/m2 on rocky substrate; biomass varied from 0.017 (17.05.2017) to 34.857 (19.08.2016) kg/m2 on soft substrate and from 1.531 (27.11.2016) to 46.147 (19.08.2016) kg/m2 on rocky substrate. Maximal development of benthos was registered in summer period. Quality of marine environment on the AMBI and M-AMBI indices was assessed as Good in 21 cases out of 23 and as Moderate in 2 cases 2 out of 23. Mean values of AMBI and M-AMBI indices for different seasons made respectively: May, 2016 – 2.56 and 0.59; August, 2016 – 1.86 and 0.69; November, 2016 – 1.70 and 0.71; June, 2017 – 1.87 and 0.75.

Оцінка процесів евтрофікації водних об’єктів річки Стрижень

According to the results of hydrological, hydrochemical and hydrobiological studies (May-October 2017) the estimation of eutrophication processes in water bodies of the Stryzhen River within the city of Chernihiv is presented. The seasonal dynamics of abiotic and biotic factors which form the water quality and trophic level of water bodies has been analyzed. It was found that the features of the hydrological regime of the Stryzhen River in 2016–2017 were low water content, the offset of the passage and a decrease in the duration of the spring flood. The volume of spring runoff was very low and reached 65% of the total annual runoff. Due to the moderate and heavy rains the water level rose slightly to 5-10 cm. It was established that at this time the movement of water in the channel sections of the reservoirs was absent. The important hydrodynamic characteristics of the ponds from an environmental point of view are mixing and wind-generated waves which cause horizontal and vertical migration of substances and enhance the self-purification capacity of water in the ponds. In the spring and summer, when forming a direct temperature stratification, the thickness of the surface layer of water which took part in the mixing processes in the first, second and third ponds was 0.5, 1-2 and 1 m, respectively. The thermocline divided the water column vertically into two parts, which differed from each other in temperature values, as well as in dissolved oxygen content and saturation, pH values, concentrations of ammonium nitrogen, nitrate ions and inorganic phosphorus. The surface layer of water was characterized by enough concentration of dissolved oxygen, whereas in the water column below the thermocline its deficiency was observed. In spring and summer there was alkalinization of the water in the surface layer of the ponds, which was caused by displacement of the hydrocarbon-calcium balance as a result of photosynthetic activity of algae. Under anaerobic conditions the concentration of ammonium nitrogen and inorganic phosphorus in the bottom water layer increased to 1.29–9.99 mgN/dm 3 and to 0.39–4.76 mgP/dm 3 respectively, the maximum values of which were observed in the first pond. During studies of the ponds of the Stryzhen River, it was found that phytoplankton was characterized by a rather rich species diversity of algae and high quantitative development rates that reached the level of water “blooming” due to the massive development of blue-green algae in July and October 2017. The species composition of macrozoobenthos in the studied ponds of the Stryzhen River was very poor, in total 35 species were found. The most favorable conditions for the development of benthic organisms were found in the river section above the third pond and below the first pond before the Stryzhen River flows into the Desna River. Bioindication analysis showed that the zoobenthos in the studied ponds was in a depressed state (TBI = 1-2), but in flowing river sites it was in the best conditions (TBI = 8). According to most of the studied indicators, water quality corresponded to categories 2-5, but content of dissolved oxygen and an inorganic phosphorus belonged to category 6-7 environmental water quality classification. According to the trophic index the studied ponds belonged to mesotrophic, but during “blooming” of water - to hypertrophic.

Quantitative Composition of Macrozoobenthos in Rivers Alindjachay and Gilanchay

Quantitative Composition of Macrozoobenthos in Rivers Alindjachay and Gilanchay

Komunitas Makrozoobentos di Sungai Gua Pintu Ngalau pada Kawasan Karst di Sumatera Barat

Pintu Ngalau cave is flowed by river from irrigated rice fields that flows into the cave. This cave has a source of organic matter derived from bats and swallow dirts, litter that falls on enterance of the cave and the organic material carried by the flow of the river. The study on the macrozoobenthos communities of river in Pintu Ngalau Cave has been conducted from October until November 2016. The study used survey method, where stratified random sampling was applied in three zones (light zone, dim zone and dark zone) at study site. Macrozoobenthos samples was collected by surber net. This study also measured the physic-chemical of water. The results showed the composition of macrozoobenthos in the Pintu Ngalau cave river consisted of 43 genera i.e Gastropods (2 genera), Hirudinea (2 genera), Insects (36 genera) and Oligochaetas (3 genera). Total density of macrozoobenthos in this site was 2100 ind/m2 and the highest density was found in dark zone. The highest total relative density (KR total=79,89%) on genus level at every zone was Hydropsyche. Diversity index of macrozoobenthos was classified as medium (H'=2.68) with evenness distribution was evenly (E=0.61) and no dominant genus (C=0.14). The existence of macrozoobenthos was not influenced by light intensity, but instead was more influence by the condition of the substrate and the flow of water in the cave.

Macrozoobenthos diversity of the Middle Ob river tributaries

The data show quantitative and qualitative composition of macrozoobenthos of the 12 left-bank confluences of the Middle Ob. The research has documented the presence of various groups, such as Oligohaeta, Diptera, Odonata, Hirudinea, Tabanidae, Trichoptera and Mollusca. The chironomids, molluscs and leeches play a significant role in the generation of biomass in the surveyed streams, and the abundance mostly depends on chironomids, oligochaetes and leeches. In general, zoobenthos abundance ranges from 8.8 (the Shudelka river) to 1839.9 (the Kochebilovka river) ind./m2, biomass is from 0.08 (Tatosh river) to 8.37 (Lozunga river) g/m2. The amount and benthos biomass of the Middle Ob’s second-order tributaries is higher than in the first-order tributaries.