Species diversity of unionid mussels (Mollusca: Bivalvia: Unionidae) as a bioindicator of the state water environment of river basins of Ukraine

Species diversity and frequency index of bivalve mollusks’ of unionid family are researched within river basins of Ukraine. The largest frequency index of mussels is identified in the Prypiat and Desna basins (84 and 79% respectively), then (as the indicator declines) – the Dnieper and Severskiy Donets basins (74 and 67%), the Southern Bug and Danube (47 and 46%), the Southern and Western Bug (47 and 28%), the Crimea (17%). No mollusks were found in the Azov basin at all. Most often (33%) there were found groups consisting of only three unpretentious species (Unio pictorum, U. tumidus, Anodonta anatina). In general, settlements from one to three species make up 70% of all researched collecting sites. Settlements formed by four species are identified only in 23% of habitats. Only 6% of settlements consisted of five aboriginal species and about 1% – of six. Locations where six species lived together were identified only in the Danube and Prypiat basins. There are no settlements of five species in the Western Bug and Desna basins at all, and there are not any even four species settlements in the Crimea. The obtained data can be used for organizing environmental activities and assessing water environment quality

Complex Assessment and Forecasting of Chemical Pollution of Small Rivers by Economic and Mathematical Modelling Methods

The purpose of this work is to determine the hydrochemical parameters of the water of the river Seret and the features of the accumulation of heavy metals by bivalve molluscs Unio pictorum L. to predict the chemical contamination of the reservoir in the near future. Water samples for the study were taken in spring (April) and summer (July) from the Seret River at two points: above and below Ternopil. It is established that the chemical composition of the water of the river Seret is formed under the influence of a number of factors, but seasonal and anthropogenic factors play a dominant role. In the spring season, a number of hydrochemical indicators (pH, water hardness, concentration of ΝΟ 2-, ΝН4+, Сl- ions and metals) have lower values than in the summer. In addition, there is an increase in the amount of organic matter, ammonium cations, nitrite ions, chloride ions, phosphate ions and a decrease in oxygen concentration below Ternopil, especially in the summer season. This is evidence that the Seret River is under significant anthropogenic impact. An increase in the concentration of metals (Mn, Cu and Pb) in summer below Ternopil was revealed, which may be due to the discharge of insufficiently treated wastewater. The series of metal concentrations in the water of the Seret River looks as follows Mn → Zn → Pb → Cd → Cu, and the series of accumulation of metals in the tissues of molluscs Unio pictorum L. has the form Zn → Mn → Cu → Pb → Cd. On the basis of bioaccumulation coefficients of heavy metals by molluscs, a prediction of the situation on their content in water for the short term based on the theory of Markov chains was made. This theory allows us to make forecasts of a factor, taking into account the possibility of accidental influences on the environment, and to investigate the highest probability of finding a factor in a certain numerical parameter. The possibility of using economic and mathematical modelling tools and statistical methods based on correlation-regression analysis using modern Matlab information systems to identify correlations between chemical indicators of water quality and biological molluscs for modelling the environmental situation of the river Seret and assessing the contribution of the studied indicators in pollution of small rivers is shown.

Биоценотические связи инвазивного вида Sinanodonta woodiana (Lea, 1834) с местными видами пресноводной фауны Украины

Вивчено міжвидові зв’язки інвазивного виду Sinanodonta woodiana з місцевими видами прісноводної фауни України (на прикладі ставу на річці П’ятигірка, село Романівка, Житомирська область). Половина досліджених особин китайської беззубки (45,1%) була населена симбіонтами.Змішані вторгнення спостерігалися у 17,4% особин. Серед виявлених симбіонтів можна виділити облігатних (інфузорії роду Conchophthirus і Trichodina, Aspidogaster conchicola), і факультативних (Helobdella stagnalis, личинка Chironomus sp.). Патологічного впливу паразитів (тріходін і аспідогастрів) на організм беззубок не встановлено. Найменша частота трапляння симбіонтів (11,1%) спостерігається у 2-річних особин китайської беззубки, і в них знайдений тільки один симбіонт – це інфузорія Conchophthirus sp. У 3-річних молюсків виявлено вже чотири симбіонти (частота трапляння – 44,4%). Тільки личинки Chironomus sp. оселяються в 4-річних і більш старших особинах. Інтродукція китайської беззубки негативно впливає на місцеві види перлівницевих. Так, після появи в ставку S. woodiana щільність поселення аборигенних видів Unio pictorum і Anodonta anatina значно знизилася – з 3,6 ос./м2 (у 2005 році) до 0,2 ос./м2 (у 2020 році). Отже, інвазивний вид S. woodiana вступає в біоценотичні зв’язки трьох типів (симбіоз, нейтралізм, антибіоз) і здатний істотно впливати на природну біоту водного середовища проживання.

Proximate Composition of Freshwater Mussels (Unio Pictorum, Linnaeus 1758) in Karasustream, Sinop

The effects of environmental factors and reproductive activities on proximate composition of freshwater mussels, Unio pictorum, was investigated from February 2013 to February 2014 in Sinop, Turkey. Environmental parameters including total particulate matter, inorganic matter and organic matter, chlorophyll-a and temperature were determined monthly during the experimental period. Mean protein, lipid, moisture and meat yield were 56.03±0.79%, 4.42±0.31%, 82.19±0.21% and 21.75±0.91%, respectively. The obtained data indicate that the proximate composition of mussels is highly correlated with environmental factors and reproduction cycle. In conclusion, freshwater mussel based protein should be evaluated an alternative source of protein for the feed industry.

Behavioral responses of freshwater bivalve mussel Unio pictorum to household derivatives of petroleum products

Petroleum products are one of the most common pollutants in water environments. Despite the fact that they do not belong to the mass of particularly dangerous toxic substances, their presence in the surface film, in dissolved form and sedimentary material adversely affects the life of marine and freshwater native flora and fauna. The list of sanitary and epidemiological rules and regulations “Zones of sanitary protection of water supply sources and drinking water pipes” specifies only general cartographic and design requirements. Thus, the purity and safety of fresh water used for irrigation and human activity without regular monitoring remains questionable. Bioelectronic monitoring of oil pollution in water sources using laboratory flow systems or submersible autonomous meters is becoming more and more relevant. Since field experiments with in these studies are in most cases impossible, it is logical to base on the results of laboratory experiments that are as close as possible to natural conditions. Under laboratory conditions, the possibility of automated detection of some common household derivatives of petroleum products in surface water sources is evaluated using a bioelectronic complex and bivalve freshwater mollusks (Unio pictorum) as part of environmental monitoring. The probability of actual detection of used petroleum products is estimated as “high” for diesel fuel, “medium” for kerosene and white spirit, and “low” for engine oil and brake fluid. The probability of detection as toxicants: “high” for diesel fuel, “medium” for white spirit, “low” for kerosene, engine oil and brake fluid.

Histopathological and Biochemical Biomarker Response of Mussel, Unio Pictorum, to Carbamate Pesticide Carbaryl: A Laboratory Study

An experiment was conducted to assess the effect of different concentrations of the insecticide carbaryl on histological and biochemical parameters including (SOD, GSH, rGSH, CAT and MDA) on gills tissue of freshwater mussel Unio pictorum for 96 hours. Significant increase in SOD and rGSH activities was observed in a concentration- dependent manner. However, statistically significant decrease in GSH levels was observed only at highest concentration. MDA levels reached higher rate at high concentration of carbaryl treated group. Mussels show behavioral responses during exposure by exhibiting increase in duration for shell closure and increase in mucus secretion. The histopathology of gills indicated that higher doses of carbaryl resulted in massive destruction in normal architecture of gill tissue. Molluscs accumulate contaminants in their body tissues and thus are used as bio-indicator for evaluating water quality and habitat degradation.