Biota Species Research Articles

Assessment of the Quality and Human Health Risk due to Heavy Metals Concentration in Marine Biota Species

Assessment of the Quality and Human Health Risk due to Heavy Metals Concentration in Marine Biota Species

Attributive analysis of the anthropophytes fraction as part of the urban flora of Kyiv urban area (the degree of naturalization, invasive status, threat assessment for local ecosystems and biotic diversity)

International ecological scientific community pays special attention to urbanized territories as separate locations of alien invasive species of biota. The results of the attributive analysis of the structure of the alien fraction of KUA flora according to three current European categories are presented. The basis of the analysis is the final list of alien vascular plants of KUA flora, which contains 718 species. 166 taxa of alien vascular plants that immigrated to KUA from 2003 to 2023 were added to the list. It was found that the degree of naturalization of immigrant species is dominated by casual alien species, which make up 59.0% of the taxonomic composition of the fraction. Species that are elements of man-make environments reach 35.5%. At the same time, alien species that grow and persist for a long time in natural habitats, including protected areas, do not exceed 5.0%. According to the categories of invasive activity, there are species that are naturalized and do not show a tendency to invasions — 32.0%. The most dangerous among invasive plants are transformer species, represented by 2.5%, actual invasive species — 4.0%, potentially invasive species — 2.0%. Based on the «Classification of alien species according to their impact on the environment», adapted by the IUCN: the massive impact is 1.5% of the total number and 4.0% of the number of naturalized ones; accordingly, the major impact — 2.2% (5.4%); the moderate impact — 5.2% (11.2%); the minor impact — 28.1% (68.6%); the minimal impact — 4.2% (10.8%). Based on the results of screening the negative effects of invasive species on the environment, examples of threats are given. This is competition for natural resources, displacement of native plant species; penetration into forests of plants whose climamorphotypes are absent in local forest ecosystems (tree vines), etc. Threatening cases of spontaneous hybridization of immigrant species with local species and with each other have been identified (repeated occurrences in the genera Bidens L., Populus L., Reynoutria Houtt., etc.). The need for an experimental study of the chemical and physical negative effects of invasive plants on local species of biota and human health is indicated. It is noted that the flora of KUA, on the background of the flora of Europe, is currently uniformly affected by phytoinvasions as an urbanized spatial unit of Ukraine.

Enhancing endangered species monitoring by lowering data entry requirements with imputation techniques as a preprocessing step for the footprint identification technology (FIT)

Numerous species of Earth's biota are at risk of extinction and wildlife conservation is more important than ever. Reliable baseline data are essential for wildlife management to inform on the numbers and distribution of endangered species. A promising non-invasive and cost-effective method for monitoring endangered species is the Footprint Identification Technology (FIT). It lends itself to both conservation research as well as citizen science and can be combined with other data collection methods. FIT extracts and uses morphometrics from animal footprints to create geometric profiles that are analyzed in customized classification models. These can identify species, sex and individual. The ability to identify individuals can then be used to predict various population parameters including size, distribution, and growth rate. FIT has been developed and published for several species, but it requires high quality footprints. Perfect prints are not always easy to find in the field as various factors can influence their quality. In this paper, we demonstrate that geometrical profiles derived from poor quality footprints can be seen as datasets with missing values. Missing values are a common problem in various disciplines, and well-established strategies to impute missing values are widely available. We conducted two experiments to see whether such an approach could widen the application of the FIT method. The experiments were designed to test the hypothesis that population sizes can be underestimated when incomplete footprints are discarded from the data. We artificially introduced different proportions of missing values in datasets with geometric profiles of five different species for which FIT models have been published. We also analyzed a new dataset of geometric profiles of cheetah (Acinonyx jubatus) footprints not meeting the standard FIT requirements. We demonstrated that excluding incomplete footprints led to an underestimation of the known population. As an alternative to discarding footprints, we compared different imputation techniques as data pre-processing steps by comparing the performance of resulting FIT models.When imputation was chosen instead, we could show that FIT models with imputed geometric profiles were not significantly less accurate in predicting individual ID or population size even with high rates of missing values. We believe that our findings can be generalized, and the results indicate that imperfect footprints can contribute to the robustness of the FIT method and that this approach is particularly applicable when few good-quality footprints are available. We therefore highly recommend including imputation of imperfect footprints as a data pre-processing step.

Biodiversity centers of fauna in the urbanized landscape of Eastern Podillia: taxonomic richness and conservation prospects

Statement of the problem and goal. Vinnytsia region now demonstrates one of the lowest indicators of provision of natural protected areas and objects (2.27% of the region’s area). The regional figure for Vinnytsia is even lower, which is 1.65% of the city’s area. The need of the day is to study the localities of rare species of biota, rare biotopes, and migration routes of animals in an urbanized environment as potential objects for the development of protected areas. Materials and methods. Determination of the optimal methodology for identifying the taxonomic structure and ecological groups of the studied fauna based on the analysis of literary, cartographic, and stock materials. To assess the geocomponent representativeness of the fauna of the urban environment, expedition research methods were used. Systematization of terrestrial and terrestrial-aquatic taxonomic groups of fauna was carried out using empirical methods. Identification of characteristic traces and remains is used to record animals through visual observation. Audio Moth v.1.2.0 recording devices and an Echo Meter Touch 2 active bat detector were used to record owls (Strigiformes, Aves) and bats (Chiroptera, Mammalia). With the help of control catches, as well as through analysis of the catches of amateur fishermen, the species composition of fish was established. Results and discussion. Under conditions of significant technogenic transformation of the biotopes of the tract and nearby aquatic landscapes, a relatively rich zoocenosis has formed. This zoocenosis unites synanthropic and local species of birds, reptiles, mammals, amphibians and fish. This is facilitated by the combination of a wide range of facies that provide the trophic and topical needs of animals. The territory of the tract, thanks to the rich species composition of animals and stable interspecies connections, can effectively serve as a center for the conservation of biodiversity and an educational, ecological and aesthetic mission in an urban landscape. Scientific novelty. A specific faunal complex of the park, the mouth of the town of Tyazhilivka and the adjacent part of the Sabarovskoe reservoir has been identified. It includes 104 species of animals of the genus Chordata: class Mammals (Mammalia) - 14 species, class Birds (Aves) - 66 species, class Reptiles (Reptilia) - 4 species, class Amphibians (Amphibia) - 4 species, class Orthoptera (Actinopterygii) – 16 species. Research materials are the basis for the creation of a nature conservation area and the expansion and optimization of the existing natural reserve network of the urban environment.

The Diversity of Mollusks (Bivalve and Gastropod) in the Intertidal Zone of Mutun Coastal, Padang Cermin, Lampung

Mutun Coastal has a diversity of biota species. Biota that are commonly found include the mollusk phylum (Bivalve and Gastropod classes). The purpose of this study was to determine the diversity of mollusks (Bivalves and Gastropods) on Mutun Coastal Lampung. This research was conducted on February 5-7, 2021. The method of data retrieval at both stations used the belt transect method by purposive sampling. Station I is substrated fine sand, while station II is substrated by coarse sand. Based on the research conducted, 26 individuals were found consisting of 7 families, namely 6 families of the Gastropod class (Trochidae, Strombidae, Cerithiidae, Muricidae, Potamididae and Pisaniidae) and 1 family of the Bivalve class, namely the family Mactridae. The value (H') at station I is 1.44. At station II it has an H' value of 0.86. The value of H' at station I belongs to the medium category. The H' value at station II belongs to the low category. The value of E at station I is 0.72. While at station II it has a value of 0.1. The evenness value at station I belongs to the high category. The value (E) at station II of the evenness index belongs to the low category. The value (D) at station I is 0.57. While at station II it has a value of 0.35. The value of D at station I belongs to the medium category. The value of D at station II belongs to the medium category. Based on data analysis, Mutun Coastal has suitable habitat for mollusk and it is also supported by abiotic parameter conditions.

Stand structure is more important for forest productivity stability than tree, understory plant and soil biota species diversity

IntroductionThe stability of forest productivity is an important management goal in order to sustain ecosystem services for an expanding human population and in the face of global climate change. Evidence from theoretical, observational, and experimental studies has demonstrated that higher biodiversity promotes stability of forest productivity. However, the majority of these studies have focused solely on tree diversity and have neglected the potentially important role of understory plant and soil biodiversity.MethodsIn this study, we explain the effect of tree, understory woody and herbaceous plant, and soil biota (fauna, fungi, and bacteria) species diversity on forest productivity and its stability over time (2000–2020) across an area of Northeast China covering 145 million hectares. We explore the eight stand structure variables for stability of forest productivity and the relationship between productivity stability and tree, understory plant, and soil biota species diversity.ResultsOur results show no significant, direct impact of understory plant, soil fungi, and bacteria species diversity on the stability of the forest ecosystem. Tree species diversity indirectly affects productivity stability by directly influencing stand structure, whereas soil fauna species diversity indirectly influences stability through its relationship with tree species diversity. Stand structure is more important than tree and soil fauna species diversity for forest productivity stability. Specifically, increasing crown height (CH) from its minimum to maximum value leads to a substantial gain of 20.394 in forest productivity stability. In contrast, raising tree species diversity (α-Tree) and soil fauna species diversity (α-Fauna) from their minimum to maximum values results in a modest reduction of only 0.399 and 0.231 in forest productivity stability, respectively.DiscussionTo increase the stability of forest productivity in response to climate change, we should adjust the stand structure more in the process of management rather than just considering biodiversity. Overall, this study highlights the ecological risks associated with large-scale biotic homogenization under future climate change and management practices.

FOREST DEGRADTION DUE TO BUSINESS ACTIVITIES (CASE STUDY IN THE PBPH AREA OF PT WIJAYA SENTOSA, TELUK WONDAMA REGENCY, WEST PAPUA)

Timber companies in West Papua operate within a strict regulatory framework set by the government and efforts to manage forests sustainably. The study aims to determine the environmental impact of logging around the PBPH area of PT Wijaya Sentosa, Teluk Wondama Regency, West Papua. The research method used is mixed using secondary data from AMDAL documents and RKL-RPL implementation report documents for 2019-2023. The study's results in the last five years have shown a decrease in abiotic components (increased noise, decreased surface water quality, and decreased air quality) and decreased biotic components (decreased biodiversity, decreased diversity of aquatic biota species). Changes in positive impacts on social components (job opportunities, opening up business opportunities, increasing community income). Balancing the various interests and stakeholders in forest management is crucial to achieving sustainable results. As well as empowering local communities, improving law enforcement, and coaching.

Macronutrient Content of Sipunculus nudus as an Antistunting Candidate

Consuming balanced nutritious food with macronutrient content including carbohydrates, protein and fat for pregnant and breastfeeding mothers as well as children under five during the growth and development period is one of the efforts to prevent and treat anti-stunting, up to the age of 2 years. Waters and beaches are one of the habitats for marine biota such as bivalve shells, gastropods, various fish and other marine biota whose names and uses are not yet popular but are widely consumed by coastal communities, including Sipunculus nudus. Marine biota from the phylum Sipuncula in some areas are called sea worms, are one of the marine biota whose habitat is in the sand, and are the favorite food of coastal communities. Information about the nutritional and mineral content of this marine biota species has not been widely reported. This research aims to determine the macronutrient content of Sipunculus nudus collected from the coastal waters of Samboang, South Sulawesi. Determination of macronutrients was carried out using several methods, including for protein using the Kjeldahl method, fat using extraction with n-hexane solvent, water and ash content using an oven and furnace. The results of measuring the macronutrient content of Sipunculus nudus showed a water content of 72%, ash content of 1.19%, protein content of 6.5%, fat content of 2.07% and carbohydrate content using difference calculations was obtained at 18.24%.

Isolation and Selection of Extracellular Enzymes in Sponge Symbiont Bacteria (Porifera: Demospongiae) from Tablolong Beach

Marine biota has many benefits for human life. Sponges are a species of marine biota that can be used as a producer of antimicrobial compounds. The bacteria found in sponges have an important role in the continuity of life in the sea. The symbiotic lifestyle that occurs in bacteria and sponges has the opportunity to form substitutions for the content of secondary metabolites and enzymes, especially extracellular enzymes (amylase, protease, cellulose and lipase). This study aims to determine how to isolate sponge symbiotic bacteria and identify spongy symbiotic bacteria. The method used is purposive to take sponges. Characterization of bacteria was carried out based on morphology and gram staining. Enzymatic bacterial selection was carried out by testing the activity of the amylase enzyme (soluble starch), lipase enzyme (Teen 80), protease enzyme (skim milk) and cellulose enzyme (carboxyl methyl cellulose). Data analysis was performed in a qualitative descriptive manner by measuring the clear zone in the extracellular enzyme test results. Meanwhile, other research parameters measured in this study were temperature, salinity and pH. The results showed that out of 47 isolated bacteria and 33 of them had extracellular enzymes with 10 bacteria had amylase enzymes, 27 bacteria had lipase enzymes, 2 bacteria had protease enzymes and 1 isolate had cellulose enzymes.

Short Communication: The biodiversity of aquatic organisms in Anak Laut Lake, Aceh Singkil District, Indonesia

Abstract. Muhtadi A, Leidonald R, Yolanda O, Harahap R, Matondang NP, Putri K, Simamora LFM, Sitompul G. 2023. Short Communication: The biodiversity of aquatic organisms in Anak Laut Lake, Aceh Singkil District, Indonesia. Biodiversitas 24: 4837-4844. Anak Laut Lake is a unique and strategic coastal lake, significantly recognized for its diverse marine biota and the potential to be a spawning, nursery, and feeding ground. Therefore, this research aimed to determine the types of aquatic organisms, including plankton, fish, crustaceans, benthos, seagrasses, and mangroves in Anak Laut Lake. The experiment was conducted in October 2022 in the Anak Laut Lake ecosystem, North Singkil Sub-district, Aceh Singkil District, Aceh Province, Indonesia. The plankton was taken using a plankton net tool, extracted vertically from a depth of 2 m, and pulled to the surface. Fish and crustaceans were observed and caught with purse seines, ring nets, and gill nets. Benthic organisms were directly observed on the edge of the lake, along with the identification of mangroves, while at the bottom, the fishermen dove into the water. The data obtained were analyzed descriptively and compared with similar research. The results showed a rich biodiversity in Anak Laut Lake, with at least 165 species/genera of aquatic biota, 9 species of mangroves, and 2 Seagrass species. The marine nekton found consisted of fish (55 species), shrimp (3 species), and crabs (10 species). The macrozoobenthos found in Anak Laut Lake consisted of 13 species of clams, 12 gastropods, 3 sea cucumbers, 2 sand dollars, 2 horseshoe crabs, and 1 sea urchin. Various species of aquatic biota whose existence was threatened in nature and found in this lake included golden sea cucumber (Stichopus herrmanni), seahorse (Hippocampus comes and Hippocampus kuda) with Vulnerable status (VU), tap ray (Maculabatis gerrardi), and sand cucumber (Holothuria scabra) with Endangered species status (EN). This shows that this coastal lake is an important and crucial habitat for several species that are vulnerable to extinction. For this reason, in the future, further studies are needed regarding the habitat characteristics and spatial and temporal distribution of aquatic organisms in Lake Laut, so that more appropriate management can be implemented for the sustainability of the lake.

Value Chain Analysis of the Marine Ornamental Reef: A Case Study in Banyuwangi, East Java, Indonesia

Coral is the main component of coral reefs and forms an ecosystem that is home to approximately 93 000 species of marine biota. In their development, corals are traded and become decorations in aquariums because of their beauty. Currently, in Indonesia, the trade in ornamental corals is still on an export scale, including hard coral species, which are strictly monitored because some are included in the Convention on International Trade in Endangered Species of Wild Fauna and Flora Appendix II. This research aimed to analyze the ornamental coral value chain at an ornamental coral company in Banyuwangi related to value-added activities, governance, and profit margins to see economic and environmental sustainability using the Porter value chain. The results showed that the primary activities that still needed to be more optimal were operational activities and outbound logistics, environmental factors (weather conditions), and improper handling causing coral death or damage (wounds). Meanwhile, the secondary activities that could have been more optimal are infrastructure and technology development. The profit margin obtained by the company was 97 523.53 US dollars with a value of 45.16% of revenue, showing that the business is profitable. Therefore, infrastructure improvements and technology development are still needed for optimal results. Further research is recommended to be conducted in relation to business development strategies and improvement of coral quality and packaging processes. Additionally, in order to support better traceability and long-term business sustainability for corals, the dearth of historical data on the ornamental coral trade in Indonesia needs to be tackled.

DIVERSITAS TERIPANG (HOLOTHUROIDEA) DI ZONA INTERTIDAL PANTAI MARINA WAKATOBI

The presence of sea cucumbers does not attract much attention, but their presence greatly influences the richness of marine biota and the diversity of biota species in the waters. Live in groups or spread out and are widely found in waters with a substrate of sand, coral sand, or sand mixed with mud. The substrate for Marina beach waters is sand, sand dominated by sea grass, sand with a little Acropora type coral, and sand mixed with mud and stones. Such conditions allow the growth and development of sea cucumbers. This study aims to determine the diversity of sea cucumbers (Holothuroidea) in the intertidal zone of Marina Wakatobi beach. This type of research is an experiment with cruise methods covering an area of ​​+ 500m2 in the intertidal zone of Marina Wakatobi beach. The types of sea cucumbers found were Synapta maculata, Holothuria scabra, Holothuria atra, Actinopyga echinites, Bohadschia marmorata, Holothurian hilla. Holothuria scabra is a type of sea cucumber that has a high distribution.

Occurrence, bioconcentration, and human health risks of pharmaceuticals in biota in the Sea of Marmara, Türkiye

The presence, bioconcentration, and health risk via seafood consumption of 11 pharmaceutical compounds belonging to different therapeutic groups (anti-inflammatory, antiepileptic, lipid regulators, and hormones) were investigated in the muscle tissues of fish and the meat of shrimp in the Sea of Marmara. Six biota species (Merlangius merlangus, Trachurus meditterraneus, Serranus hepatus, Pomatomus saltatrix, Parapenaeus longirostris, Spratus sprattus) were collected from the five stations in October and April 2019. Ultrasonic extraction method followed by solid phase extraction was used for extraction of pharmaceutical compounds from biota samples and then analyzed using high-performance liquid chromatography. Of the 11 compounds, 10 were detected in biota species. Ibuprofen was the most frequently detected pharmaceutical in the biota tissues at high concentrations (<3.0–1225 ng/g, dw). The other widely detected compounds were fenoprofen (<3.6–323 ng/g, dw), gemfibrozil (<3.2–480 ng/g, dw), 17α-ethynylestradiol (<2.0–462 ng/g, dw), and carbamazepine (<7.6–222 ng/g, dw). The bioconcentration factors of the selected pharmaceuticals calculated in various aquatic organisms ranged from 9 to 2324 L/kg. The estimated daily intakes of anti-inflammatories, antiepileptics, lipid regulators, and hormones via seafood consumption were 0.37–568, 1.1–324, 8.5–197, 3–340 ng/kg bw. Day, respectively. Based on hazard quotients, estrone, 17β-estradiol, and 17α-ethynylestradiol may pose a health risk to humans through the consumption of this seafood.

Investigating microplastic contamination and biomagnification in a remote area of South Australia

Context Microplastics are widespread in aquatic ecosystems and are commonly recorded in water, sediment and a broad spectrum of marine biota. Yet, the extent to which organisms ingest microplastics directly or indirectly by trophic transfer is largely unknown. Aims This study characterises microplastic abundance across intertidal water, sediment, and marine biota species of different trophic levels, and investigates whether biomagnification occurs. Methods Water, sediment, molluscs, crustaceans and fish were sampled from a single area in southern Australia. Key results Microplastics were recorded in 35% of water, 45% of sediment and 39% of biota samples. Plastic load was 0.36 ± 0.08 microplastics g−1 DW for sediment, 0.50 ± 0.17 microplastics L−1 for water, and 0.70 ± 0.25 microplastics individual−1 for biota. Biomagnification was not found, although similarities in plastic characteristics across biota may imply trophic transfer. Most of the microplastics were fibres (97.5%) of blue, black and transparent colour. Spectral analysis (μ-FTIR) indicated that polyester (50%) and polyethylene (42.3%) dominated the polymer compositions. Conclusions There were no significant differences in microplastic contamination among biota species, with no biomagnification identified. Implications We provide information on biomagnification of microplastics alongside a still uncommon characterisation of contamination in water, sediment and biota.

Intestinal preservation in a birdlike dinosaur supports conservatism in digestive canal evolution among theropods

Dromaeosaurids were bird-like dinosaurs with a predatory ecology known to forage on fish, mammals and other dinosaurs. We describe Daurlong wangi gen. et sp. nov., a dromaeosaurid from the Lower Cretaceous Jehol Biota of Inner Mongolia, China. Exceptional preservation in this specimen includes a large bluish layer in the abdomen which represents one of the few occurrences of intestinal remnants among non-avian dinosaurs. Phylogenetically, Daurlong nests among a lineage of short-armed Jehol Biota species closer to eudromaeosaurs than microraptorines. The topographic correspondence between the exceptionally preserved intestine in the more stem-ward Scipionyx and the remnants in the more birdlike Daurlong provides a phylogenetic framework for inferring intestine tract extent in other theropods lacking fossilized visceral tissues. Gastrointestinal organization results conservative among faunivorous dinosaurs, with the evolution of a bird-like alimentary canal restricted to avialan theropods.

The role of the Pamir Botanical Garden in the enrichment of the assortments of conifers in the Western Pamirs

This article presents some results of cuttings of coniferous plants in the conditions of the Western Pamirs, on the example of the Pamir Botanical Garden, as well as enriching the range and prospects for their use. Since under natural conditions, the diversity of conifers in the Pamirs is very small and mainly species of the juniper genus grow here, in the Pamir Botanical Garden, for many years, research has been carried out to study the introduced coniferous plants and their adaptation to the conditions of this territory. In the course of the study on introduction, the optimal cutting time was determined for species of spruce, biota and others. It is shown that the spring period of grafting in comparison with the summer period is the most optimal for the conditions of the Western Pamirs. It was determined that western thuja (Thuja occidentalis) has a very good percentage of survival (60 %) compared with prickly spruce and European spruce, which are inferior to it by 15-20 %. The article also gives a brief description of conifers that have already been acclimatized in the conditions of the Western Pamirs and there is a prospect of their use for landscaping and soil protection in different parts of this territory. These include species of the genus biota, thuja, spruce and others.

Investigation of the cytotoxic, anti-proliferative and anti-angiogenic effects of Toluhydroquinone on Caco-2 cell line.

Colorectal cancer is one of the most common types of cancer in the world. The treatment options for colorectal carcinoma generally consist of surgery, radiotherapy and chemotherapy. The drug resistance to chemotherapy agents used in the current cancer treatment has brought about the finding of new drug molecules from some plant and aquatic species in the treatment approaches. Some species of aquatic biota create novel biomolecules as potential drugs for cancer and other diseases. Toluhydroquinone belongs to these groups of biomolecules and it shows anti-oxidative, anti-inflammatory and anti-angiogenic properties. In this study, we tested the cytotoxic and anti-angiogenic effects of Toluhydroquinone on Caco-2(Human colorectal carcinoma cell line) cells. It was observed that the amount of closure of the wound space, colony forming ability (in vitro cell survivability) and formation of tubule-like structures in matrigel decreased in comparison to the control group. As a result of this study, Toluhydroquinone has cytotoxic, anti-proliferative and anti-angiogenic properties on the Caco-2 cell line.

IDENTIFICATION OF COASTAL BIOTA MANGROVE EDUCATION CENTER (MEC) USING LINE TRANSECT METHOD CASE STUDY IN PANGKALAN JAMBI VILLAGE, BUKIT BATU DISTRICT, BENGKALIS REGENCY

The Mangrove Education Center is located in Pangkalan Jambi Village, Bukit Batu Sei District. Pakning Bengkalis Regency which has the potential to be developed into a mangrove ecotourism area, because almost along the coast is overgrown with mangrove ecosystems and has abundant biota. This study aims to identify the potential of biota using the transect method as a mangrove ecotourism area. Data collection was carried out from January to February 2022 in Pangkalan Jambi. The research method used is purposive sampling. The research area was taken as many as 3 stations. Data analysis is based on the number of biota found in each station. Parameter data for mangrove tourism suitability consists of biota objects. The results of the measurement of the suitability of mangrove tourism parameters are the number of biota at station I with 35, station II at 30 and station III at 38. Found 4 species of biota with others such as: fish, shrimp, crabs, mollusks, reptiles, birds, and other biota. The results of this study indicate that this mangrove forest spans an area of ​​3 hectares along the coastline of Pangkalan Jambi Village. the most influential for the sustainability of the mangrove ecosystem.

Caddisflies Stenopsyche marmorata (Trichoptera: Hydropsychidae) exploit river mussels as anchors for their nets

In the foothill rivers of the south of Primorsky Krai (Russian Federation), during the abnormally hot summer-autumn season of 2021, the number of net-spinning larvae of the caddisflies Stenopsyche marmorata Navas, 1920 (Stenopsychidae) sharply increased. Here we describe the phenomenon of widespread use by these caddisfly larvae of the shells of live bivalves Middendorffinaia Moskvicheva et Starobogatov, 1973 (Unionidae) to attach their feeding nets. As a result, the immobilized river mussels could not move to the deeper sites for wintering, and in the coming winter season they died due to freezing into ice. The described phenomenon illustrates the indirect negative impact of climate change on vulnerable species of river biota.

Bioaccumulation and Biomagnification of Polychlorinated Biphenyls and Dichlorodiphenyltrichloroethane in Biota from Qilianyu Island, South China Sea.

Six biota species were collected from Qilianyu Island, South China Sea to determine the bioaccumulation and biomagnification of polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane and its metabolites (DDTs). Concentrations of ΣPCBs and ΣDDTs in biota from Qilianyu Island ranged from 6.88 to 519.1 ng/g lipid weight (lw) and 7.0 to 19,413 ng/g lw, respectively. Significant differences for PCBs and DDTs concentrations were found among the six biota species from Qilianyu Island. The levels of PCBs and DDTs in intermediate egret were significantly higher than the other five biota species, which can be attributed to their different feeding and living habits. Significantly negative relationships between concentrations of PCBs and DDTs and δ13C values in the six biota species confirmed that dietary source is an important factor to determine the levels of PCBs and DDTs in biota species. ΣPCBs, ΣDDTs, PCB 28/31, PCB 52, and p,p′-DDE were biomagnified in the biota species from Qilianyu Island, and native species are suitable for studying the biomagnification of the contaminants. The toxic equivalent concentrations in birds from Qilianyu Island were significantly and positively correlated with PCBs concentrations, indicating that high concentrations of non- and mono-ortho-PCB congeners may induce adverse effects on bird species.