Tadpole Shrimps – A General Review of the Little Known Crustaceans of Ephemeral Waterbodies

In time of global climate changes, astatic inland water reservoirs that contribute to water retention and alleviation of adverse effects of periodic river floods, are getting more and more important. Small, periodically drying off water reservoirs are also rich hubs of biodiversity. Animals especially connected to such ecosystems are primitive but unique crustaceans called tadpole shrimps (order Notostraca). Those animals seem to have universal significance – both ecological and economic. Though their primitive morphology and small size, they can radically affect the nature of their habitats, sometimes even helping us fight with noxious pests. Unfortunately, due to progressing global warming, intensification in agriculture, and urbanisation, habitats of notostracans are disappearing rapidly. Simultaneously, because of their rare occurences and taxonomic difficulties, tadpole shrimps have been insufficiently studied. However, protection of these crustaceans is inseparably connected with conservation of once numerous, periodically drying reservoirs as tadpole shrimps are referred as keystone species of such habitats. Thus, the aim of this review article is to sum up and disseminate current state of knowledge about Notostraca by a general overview of available international literature. This might help to engage more scientists into research and conservation of these little known, yet interesting crustaceans and their unique habitats

Hydrogen Sulfide and Silicon Together Alleviate Chromium (VI) Toxicity by Modulating Morpho-Physiological and Key Antioxidant Defense Systems in Chickpea (Cicer arietinum L.) Varieties

Extensive use of chromium (Cr) in anthropogenic activities leads to Cr toxicity in plants causing serious threat to the environment. Cr toxicity impairs plant growth, development, and metabolism. In the present study, we explored the effect of NaHS [a hydrogen sulfide; (H2S), donor] and silicon (Si), alone or in combination, on two chickpea (Cicer arietinum) varieties (Pusa 2085 and Pusa Green 112), in pot conditions under Cr stress. Cr stress increased accumulation of Cr reduction of the plasma membrane (PM) H+-ATPase activity and decreased in photosynthetic pigments, essential minerals, relative water contents (RWC), and enzymatic and non-enzymatic antioxidants in both the varieties. Exogenous application of NaHS and Si on plants exposed to Cr stress mitigated the effect of Cr and enhanced the physiological and biochemical parameters by reducing Cr accumulation and oxidative stress in roots and leaves. The interactive effects of NaHS and Si showed a highly significant and positive correlation with PM H+-ATPase activity, photosynthetic pigments, essential minerals, RWC, proline content, and enzymatic antioxidant activities (catalase, peroxidase, ascorbate peroxidase, dehydroascorbate reductase, superoxide dismutase, and monodehydroascorbate reductase). A similar trend was observed for non-enzymatic antioxidant activities (ascorbic acid, glutathione, oxidized glutathione, and dehydroascorbic acid level) in leaves while oxidative damage in roots and leaves showed a negative correlation. Exogenous application of NaHS + Si could enhance Cr stress tolerance in chickpea and field studies are warranted for assessing crop yield under Cr-affected area

Effect of Diverse Abiotic Conditions on the Structure and Biodiversity of Ichthyofauna in Small, Natural Water Bodies Located on Agricultural Lands

Mid-field natural ponds promote regional biodiversity, providing alternative habitats for many valuable animal species. The study’s objective was to determine the most important abiotic factors, including hydrochemical and morphometric parameters, affecting fish occurrence in natural, small water bodies on agricultural lands. The studies were conducted in nine randomly selected water bodies located in Poland (the North European Plain). Eleven species of fish were recorded in the waterbodies, with the most abundant being cyprinids (mainly crucian carp). Canonical correspondence analysis (CCA) showed that an increase in oxygenation, temperature, amount of macrophytes, and K concentration and a decrease in the concentration of phosphates, electrical conductivity (EC), Mg, and Cl is associated with the most beneficial living conditions for the most frequently occurring species in the studied water bodies—crucian carp and tench. Aside from the hydrochemical parameters of water in the natural ponds, the number of fish correlates with the basin area and the pond area, maximum depth, area of the buffer zone surrounding the water bodies, and the number of macrophytes. This last factor also has a significant influence on the species’ abundance in the water bodies. Fish occurrences in mid-field ponds and common knowledge on their important role in the environment require taking steps to provide fish protection

The Effect of Maintenance Works on Ichthyofauna in the Context of Hydrochemical Conditions of Small Watercourses of Central and North-Western Poland

The studies were conducted in the summers of 2017 and 2018 on three watercourses in Central and North-Western Poland, the where maintenance works involving disposal of sediment and silt were performed in the autumn of 2017. Monitoring of the ichthyofauna in the Rurzyca River and the Tywa River before (year 2017) and after the maintenance works (year 2018) indicated a decrease in the number of species. Altogether, 23 fish species were caught in all the watercourses. Out of these, 12 species were not recorded after the studied rivers had been dredged. A slight decrease in the number of fish species was observed in each studied river after the maintenance works. The values of physicochemical parameters obtained for each watercourse indicate a low quality of the waters. After silt had been removed from the watercourses, lower N-NO3values were observed at most research sites, whereas the N-NH4+ values increased significantly (except for one site on the Kanał Habdziński). Additionally, high volumes of P-PO43-were observed (except for sites 2 and 3 on the Kanał Habdziński and site 2 on the Rurzyca River). Maintenance works performed on small watercourses have a negative impact on the quality of waters and a less significant impact on the number of fish and biodiversity. This appears to be connected with migration of fish in the river during the maintenance works and avoidance of the consequent unfavourable conditions to gradually return to their habitats afterwards

Condition and population structure of the round goby (Neogobius melanostomus Pallas, 1811) in Szczecin Lagoon in 2010–2014

The round goby (Neogobius melanostomus Pallas, 1811) is one of the most invasive fish species in the world, including Poland. 300 fish of this species were collected in the waters of Szczecin lagoon between 2010 and 2014 and examination of the size, sex and age structures of the population and of the condition of the fish was performed. Total length and standard length of all the collected fish amounted to 149.2 mm (±42.21) and 128.1 mm (±38.65), respectively. The age structure of the fish consisted of nine generations, with clear prevalence of the fish aged 3+ and 4+. Mean values of condition factors for the whole fish sample amounted to 0.20 (±0.02). However, no statistically significant differences in particular years were observed (ANOVA, p > 0.05), but the condition of the fish between 2010 and 2011 was slightly higher than between 2013 and 2014. The obtained results indicate that the Szczecin Lagoon environment provides this species with favourable living conditions and it can be stipulated that the quantity of individuals of this fish species will increase

Preliminary assessment of the impact of soil microorganisms on greenhouse gas emissions expressed in CO2 equivalent and grass biomass

The pot experiment was conducted to access the soil microorganisms biomass (physiological method - Substrate Induced Respiration) and emissions of N2O, CO2 and CH4 (photoacoustic infrared detection method), and grasses biomass (weight method). The obtained results of analysed gases were converted to CO2 equivalent. There was no effect of the microorganisms biomass on the N2O emissions. The increase in CO2 emissions was accompanied by an increase in the microorganisms biomass (r = 0.48) under the conditions of the I swath and acid soil reaction, as well as the II swath and neutral reaction (r = 0.94). On the other hand, in the case of CH4 emission, such a relationship was noted both swaths under the conditions of neutral reaction (r = 0.51), but a negative correlation (r = –0.71) was noted for the acid reaction only at the II swath. The increase in the grasses biomass with the increase in the microorganisms biomass was recorded only at the II swath in neutral reaction (r = 0.91). In a short period of time, with the neutral soil reaction with the increase in the soil microorganisms biomass, an increase in CO2 sequestration and biomass of cultivated grasses was noted. Information on the determination of the microorganisms groups responsible mainly for the transformation of carbon compounds and CO2 and CH4 emissions from the soils of grasslands would be valuable scientifically

Struktura wieku, kondycja i wzrost długości czebaczka amurskiego (Pseudorasbora parva Schlegel 1842) w nierodzimych populacjach w niewielkich ciekach w Polsce

Monitoring studies of ichthyofauna, in particular non-indigenous species, are an important element of research on aquatic ecosystems. This information is essential for modelling population growth and predicting rates of expansion, quantifying ecological impacts and assessing the efficacy of removal and control strategies. Actually, the most compelling fish invasion in Polish freshwaters is arguably the accidental introduction of the topmouth gudgeon (Pseudorasbora parva). Age and lengths structure, condition factor and growth rate of the invasive populations of the topmouth gudgeon from small Polish rivers was examined. The samples were collected from the rivers: Molnica (n = 41), Myśla (n = 21) and Wardynka (n = 101) soon after the invasion was recorded (2017). Estimated ages of topmouth gudgeon ranged from 1+ to 3+ for the Myśla River, from 1+ do 4+ for the Molnica River, and from 1+ to 5+ for the Wardynka River. The fish from the Molnica River was characterised by the lowest total and standard length (TL, SL), weight, and highest condition. The results of back-calculations and the parameters of von Bertalanffy’s growth equation revealed distinct disproportions in the standard length (mm) in individual age groups (Molnica River: Lt = 54.94 [1 – e–0.68885 (1 – 0.003404)], Myśla River: Lt = 55.39 [1 – e–0.74921 (1 – 0.030962)], Wardynka River: Lt = 66.33 [1 – e–0.69348 (1 – 0.369505)]). The introduction of the topmouth gudgeon occurred in the upper and medium sectors of small rivers, but in subsequent years the species migrated to new sites further downstream and this may have affected the native ichthyofauna.Badania monitoringowe ichtiofauny, w szczególności gatunków nierodzimych, są ważnym elementem badań nad ekosystemami wodnymi. Informacje te są niezbędne do modelowania wzrostu populacji i przewidywania tempa ekspansji, ilościowego określania skutków ekologicznych i oceny skuteczności strategii eliminacji tych ryb z wód rodzimych oraz ich kontroli. Jednym z najbardziej interesujących gatunków inwazyjnych w świecie ryb w polskich słodkowodnych wodach jest prawdopodobnie przypadkowe wprowadzenie czebaczka amurskiego (Pseudorasbora parva). W pracy analizowano strukturę wieku i długości, współczynnik kondycji i tempo wzrostu inwazyjnych populacji czebaczków amurskich z małych cieków w Polsce. Ryby złowiono w 2017 r. z rzek: Molnica (n = 41), Myśla (n = 21) i Wardynka (n = 101). Szacowany wiek czebaczków amurskich wynosił od 1+ do 3+ (Myśla), od 1+ do 4+ (Molnica) i od 1+ do 5+ (Wardynka). Ryby z Molnicy cechowały się najmniejszą długością całkowitą i długością ciała (TL, SL) oraz masą osobniczą. Odczyty wsteczne i parametry równania wzrostu von Bertalanffy’ego ujawniły wyraźne dysproporcje w długości całkowitej w poszczególnych grupach wiekowych (rzeka Molnica: Lt = 54,94 [1 – e–0,68885 (1 – 0,003404)], rzeka Myśla: Lt = 55,39 [1 – e–0,74921 (1 – 0,030962)], rzeka Wardynka: Lt = 66,33 [1 – e–0,69348 (1 – 0,369505)]). Wprowadzenie czebaczka amurskiego miało miejsce w górnej i środkowej strefie małych cieków, ale w kolejnych latach gatunek ten może migrować do nowych miejsc zlokalizowanych w dolnych odcinkach rzek i może wpływać na rodzimą ichtiofaunę

Population structure and density of a new invasive species Rangia cuneata in the Szczecin Lagoon (Odra/Oder estuary, Poland)

The native North American bivalve species Rangia cuneata was unintentionally introduced into European waters during the first decade of the 21st century. In the Baltic Sea, it is mostly found along the southeastern coast, but in 2018 researchers also discovered the species in the Bay of Pomerania, which indicated that it could eventually inhabit the adjacent Szczecin Lagoon and Odra River. In 2021, the species was discovered for the first time in the Szczecin Lagoon during a sampling campaign, at 5 out of the 12 dispersed study sites with diverse bottom substrates. The goal of this study was to ascertain R. cuneata population density, morphometric parameters, individual growth, and the potential for further expansion in the southern Baltic Sea waters. For the study, 201 individuals of this species were collected. Compared to other sites in the southeast Baltic, the Szczecin Lagoon had a much lower average R. cuneata population density, at 13.2 ± 7.11 individuals m-2 of the bottom area. The highest population density was found at sites with more silt (4–63 µm) and less sand (>63 µm). R. cuneata shells had an average length of 30.9 ± 4.6 mm and an average weight of 6.6 ± 2.8 g. The collected specimens were greater in size than other populations of the species in the Baltic Sea and were comparable in size to populations from the nearby Bay of Pomerania. There were no specimens that were under 10 mm in length, and the population was dominated by specimens in the 25–30 mm and 30–35 mm ranges, as well as the 3+ and 4+ age groups. Given the R. cuneata's invasive potential and its fast rate of colonization of new areas, it would be prudent to monitor this population and the species migration patterns across the estuary waters of the western Baltic

Analiza jakości wód wybranych małych cieków zlokalizowanych w zlewni rzek Odry i Wisły

An important source of contamination of inland waters is the content of nitrogen and phosphorus compounds, which in agricultural areas constitute a significant threat by getting into flowing waters. The runoff of mineral substances from areas with high intensification of agriculture contribut to increase of nutrient content in rivers, which often causes disturbances in water quality, with excess nutrients supporting the growth of phytoplankton (algae receipts) and macrophytes and associated with it loss of habitats and desirable plant and animal species. The small rivers play an important role in the water quality of large rivers. The purpose of this work is to assess the quality of water in small lowland rivers, which are tributaries of the Odra and Wisła rivers, with particular emphasis on the content of biogenic compounds (nitrogen and phosphorus forms). The study was carried out on 10 small rivers from the Odra river basin (Płonia, Myśla, Tywa, Rurzyca and Wardynka River), and the Wisła river basin (Habdziński Channel, Zielona, Czarna-Cedron, Kraska and Molnica River). The analyzed water samples in all rivers had increased content of reactive phosphorus, which allows to classify the waters into non-class waters. The highest exceedences were recorded in the Płonia River (on average 1.505 mg P-PO43-/L) in the Odra river basin, while in the in the Wisła basin the highest exceedances were recorded in the Molnica watercourse (average 2.023 mg P-PO43-/L). Also high concentrations of the nitrate-nitrogen content were recorded, and the highest amounts of N-NO3-/L were found in the Rurzyca River (the Odra catchment – 7.321 mg N-NO3-/L) and in Molnica River (Wisła catchment – 5.092 mg N-NO3- /L). Lower values of ammonium nitrogen were found in all tested watercourses, classifying water to the first class of water quality according to Minister of the Environment Regulation (21.07.2016r.). Only increased concentrations classifying the examined waters up to the 2nd water quality class were recorded in the Rurzyca river (Odra catchment - 0.350 mg N-NO3- /L average, and in the Habdziński Channel (Wisła catchment - 0.293 mg N-NO3- /L). Significant increases in the content of biogenic compounds classifying tested waters to the 2nd class and above, were also conducive to low values of oxygen concentration in water and high conductance. For example in the Molnica river, high nitrate nitrogen and phosphate content influenced on low water oxygenation. In addition, there was a very low water level in the watercourse, which could have triggered nutrient loads in bottom sediments. Contamination of waters from agricultural areas with nitrogen and phosphorus compounds may pose a threat to larger rivers to which they can pass without proper monitoring.Istotnym źródłem zanieczyszczenia wód śródlądowych są zawartości związków azotu i fosforu, które na obszarach rolniczych stanowią znaczące zagrożenie przedostając się do wód płynących. Do nadmiernego wzrostu zawartości związków biogennych w rzekach przyczyniają się spływy substancji mineralnych z terenów o dużej intensyfikacji rolnictwa, co niejednokrotnie jest przyczyną zaburzeń jakości wody, przy czym nadmiar składników odżywczych sprzyja wzrostowi fitoplanktonu (zakwitów glonów) i makrofitów oraz związanej z tym utraty siedlisk i pożądanych gatunków roślin i zwierząt. Dużą rolę w kształtowaniu jakości wody dużych rzek pełnią niewielkie dopływy stanowiące małe cieki wodne. Celem niniejszej pracy jest ocena jakości wód w wybranych małych nizinnych ciekach wodnych będących dopływami rzeki Odry i rzeki Wisły ze szczególnym uwzględnieniem zawartości związków biogennych (formy azotu i fosforu). Badaniami objęto 10 niewielkich cieków z obszaru zlewni rzeki Odry (rzeki: Płonia, Myśla, Tywa, Rurzyca i Wardynka), oraz zlewni rzeki Wisły (Kanał Habdziński, Zielona, Czarna-Cedron, Kraska i Molnica). Analizowane próby wody we wszystkich rzekach miały podwyższone zawartości fosforu fosforanowego, co pozwala zaklasyfikować badane wody do wód pozaklasowych. W zlewni rzeki Odry największe przekroczenia norm odnotowano w rzece Płonia (średnio 1.505 mg P-PO43-/L), natomiast w zlewni Wisły największe przekroczenia zanotowano w cieku Molnica (średnio 2.023 mg P-PO43-/L). Również wysokie stężenia odnotowano analizując wody pod kątem zawartości azotu azotanowego, a największe ilości N-NO3-stwierdzono w rzece Rurzyca (zlewnia Odry – 7.321 mg N-NO3-/L) i w Molnicy (zlewnia Wisły – 5.092 mg N-NO3-/L). We wszystkich badanych ciekach stwierdzono niższe ilości azotu amonowego, klasyfikując wody do I klasy czystości wg Rozp. MŚ z 21.07.2016r. Jedynie podwyższone stężenia klasyfikujące badane wody do 2 klasy czystości wód zanotowano w rzece Rurzyca (zlewnia Odry – średnio 0.350 mg N-NH4+/L, oraz w Kanale Habdzińskim (zlewnia Wisły – 0.293 mg N-NH4+/L). Znaczące podwyższenia zawartości związków biogennych klasyfikujące badane wody doII klasy i powyżej II klasy czystości wód sprzyjały również niskim wartościom stężenia tlenu w wodzie oraz wysoką konduktancją. Przykładem jest tu rzeka Molnica, w której wysokie zawartości azotu azotanowego oraz fosforanów przekładały się na niskie natlenienie wody i wysokie przewodnictwo właściwe. Ponadto w cieku była bardzo niski stan wód, co mogło uruchomić pokłady ładunków biogennych w osadach dennych. Zanieczyszczenia wód z terenów rolniczych związkami azotu i fosforu mogą stanowić zagrożenie dla większych rzek, do których bez odpowiedniego monitoringu mogą się przedostawać

Characterisation of Benthic Macroinvertebrate Communities in Small Watercourses of the European Central Plains Ecoregion and the Effect of Different Environmental Factors

Most publications on the influence of environmental factors on macroinvertebrate communities focus on large rivers, whereas relatively few examine small watercourses in agricultural areas, which, due to their size and pressure from intensive agricultural production, are much more susceptible to the effects of unfavourable environmental conditions or anthropopressure. The aim of our study was to compare the biodiversity of macrozoobenthos assemblages and to determine the effects of physicochemical and hydrological conditions on their abundance and density in 10 small rivers in agricultural areas located in northwest (53°23′ N 15°14′ E) and central (52°11′ N 20°48′ E) Poland. In total, 105 taxa were recorded, with the majority being euryoecious. Among the assessed physicochemical parameters, oxygenation was found to affect the density and number of taxa; another important factor was the content of nitrate nitrogen. Sensitivity to changes in water temperature was observed in some macrozoobenthos taxa (especially Decapoda). Of the examined hydrological parameters, the greatest effects were exerted by speed, flow, and depth