Biosystems Diversity (E-Journal - Dnipro National University)
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Assessment of soil quality in agroecosystems based on soil fauna
Get PDFSoil arthropods respond sensitively to land management practices and correlate with beneficial soil functions. The aim of this research was to determine soil quality using the QBS index in different types of crops and influence of soil variables (pH soil, soil moisture, potassium, phosphorus and nitrogen) on soil arthropods. Between the years 2018 and 2020, we studied different types of crops (Brassica napus, Pisum sativum, Triticum aestivum, T. spelta, Zea mays, Grass mixture and Hordeum vulgare) and recorded 14 taxa. Our results suggest a higher QBS index value in crops grass mixture, Pisum sativum, Triticum aestivum, T. spelta. The EMI value grew with increasing values of soil moisture, soil pH, phosphorus, potassium and nitrogen; indicating the presence of soil arthropods occurring in higher quality soil. Our results suggest that agricultural intensification affects soil arthropods, which are important for the production of biomass, which also affects crop yields
Summer coastal rookeries and perspectives of the Baikal seal (Pusa sibirica) population in the conditions of the global warming
Get PDFBased on the secondary literature, a retrospective characterization of the climate in the Baikal region, starting from the end of the Pleistocene, is given. According to satellite monitoring data, the characteristics of the ice regime of the Lake Baikal in the conditions of climate warming are presented. Moreover, we briefly discuss the impact of climate change on the ecology and biology of the Baikal seal (Pusa sibirica Gm.). Using video materials obtained online at one of the main island coastal rookeries of seals (on the island of Tonkyi, the archipelago of the Ushkany Islands, Lake Baikal) in 2011–2017, the dependence of the number of seals hauled out on the lake level and the peculiarities of the fishing regime was determined (the survey was conducted from May–June to October). A direct relationship was determined between the relative number of animals that had a moulting delay and the ice regime of a given year: the longer the floating ice in the northern part of Lake Baikal remained, the more numerous were the first approaches of seals to the studied rookery and the greater was the proportion of moulting individuals. It is reasonable to assume that the main reason for the Baikal seal to come ashore is not prolongued moulting time, but a physiological need for sunlight, which has a healing effect on the body of animals that lack solar radiation in winter. In general, climate warming has a negative impact on the state of the Baikal seal population. The available paleoclimatic reconstructions of the Holocene indicate that the population of the Baikal seal has experienced a lot of climate changes in its history. Nevertheless, if the current trends of climatic changes persist until the end of the 21st century, the ecology and biology of the seal will drastically change (up to the beginning of terrestrial reproduction), and the population will significantly decrease. However, the Baikal seal as a species would remain
Algal and cyanobacterial diversity in saline rivers of the Elton Lake Basin (Russia) studied via light microscopy and next-generation sequencing
Get PDFNaturally saline rivers are known in various regions of the world. Saline rivers with a salinity gradient from the source to the mouth are particularly interesting, because the range of salinity is the structure-forming factor of the hydrobiont assemblage. Such rivers are represented by saline rivers of the Elton Lake Basin in Volgograd region of Russia (the Bolshaya Samoroda River and the Malaya Samoroda River). Herein, we analyzed taxonomic structure and species diversity of microalgae and Cyanobacteria of the saline rivers flowing into the Elton Lake by light microscopy and next-generation sequencing. The differences and possible causes of inconsistencies in the results obtained by these methods are discussed. In total, 91 taxa of microorganisms were identified by integrated approach in the assemblages of microalgae and Cyanobacteria in the middle course of the Bolshaya Samoroda River, and 60 taxa – in the river mouth. The species diversity of those assemblages in the hypersaline Malaya Samoroda River was lower: 27 taxa from the middle course and 23 taxa from the mouth. Next-generation sequencing allowed us to refine and expand the list of microalgae taxa in the studied saline rivers due to detection of species which were hard to identify, low-abundance taxa, as well as extremely small-cell forms. Some discrepancies between the data obtained by light microscopy and next-generation sequencing indicate the advantage of simultaneous use of both methods for study of the algae communities. Such a comprehensive approach provides the most accurate and correct list of taxa added with the morphological descriptions and 18S rRNA and 16S rRNA partial sequences. Generally, 18 taxa have been recorded for the first time in the Bolshaya Samoroda River, belonging to the phyla Chlorophyta (Borodinellopsis sp., Chlorochytrium lemnae Cohn, Caespitella sp., Halochlorococcum sp., Tetraselmis cordiformis (H. J. Carter) F. Stein), Ochrophyta (Pseudocharaciopsis ovalis (Chodat) D. J. Hibberd, Characiopsis sp., Poterioochromonas stipitata Scherffel, Chrysolepidomonas sp.), Euglenozoa (Euglena bucharica I. Kisselev, Lepocinclis tripteris (Dujardin) B. Marin & Melkonian, Phacus orbicularis K. Hübner, P. parvulus G. A. Klebs), Cryptophyta (Hemiselmis cryptochromatica C. E. Lane & J. M. Archibald, Rhodomonas sp., Hanusia phi J. A. Deane), Haptophyta (Pavlova sp.), Cyanobacteria (Johanseninema constrictum (Szafer) Hasler, Dvorák & Poulícková). Seven taxa have been detected for the first time in the algal and cyanobacterial assemblages of the Malaya Samoroda River from the phyla Chlorophyta (Tetraselmis cordiformis, T. arnoldii (Proschkina-Lavrenko) R. E. Norris, Hori & Chihara, T. tetrathele (West) Butcher, Pyrobotrys elongatus Korshikov), Cryptophyta (Hanusia phi), and Cyanobacteria (Synechococcus elongatus (Nägeli) Nägeli, Oscillatoria simplicissima Gomont)
Impact of recreational transformation of soil physical properties on micromolluscs in an urban park
Get PDFThe paper assesses the effect of transformation of soil physical properties on the abundance of micromolluscs in the conditions of an urban park. The studies were carried out in Novooleksandrivskiy Park (Melitopol, Ukraine). An experimental polygon was represented by 7 transects with 18 sampling points in each. The interval between the points in the transect, as well as the interval between transects, was 3 meters. The total area of the polygon was 1,134 m2. The tree species growing within the polygon were Quercus robur, Sophora japonica, and Acer campestre. Shrubs were represented by Ulmus laevis, Tilia cordata, Celtis occidentalis, and Morus nigra. The locations of the trees and shrubs were mapped. The crowns of tree and shrub plants formed a dense canopy and a shady light regime. The grass cover was practically absent. The soil mechanical resistance, soil aggregate-size distribution, electrical conductivity of soil, soil moisture and bulk density were measured. We recorded 618 individuals of Vallonia pulchella, 120 individuals of Cochlicopa lubrica, and 58 individuals of Acanthinula aculeata within the surveyed polygon. We extracted three principal components, which could explain 60.9% of the variation in the feature space of the soil properties. The principal component 1 explained 42.0% of the variation of the feature space and depended on the soil penetration resistance throughout the whole profile, aggregate composition, density, electric conductivity and moisture content of soil. This component reflected a tendency for soil penetration resistance and soil density to increase near recreational trails. The principal component 1 was used to indicate the gradient of recreational transformation of the soil. The principal component 2 was able to explain 10.6% of the variation in the feature space. It negatively correlated with the distance from the recreational trail, soil penetration resistance at the depth of 35 cm or more, soil electrical conductivity, and the proportion of aggregates greater than 3 mm in size. This component positively correlated with soil penetration resistance at 0–5 cm depth and the proportion of aggregates less than 0.5 mm in size. This component can be interpreted as a "halo" from the recreational trail, or a gradient of indirect soil transformations adjacent to the zone of intense recreational load. The principal component 3 was able to explain 8.3% of the variation in the feature space. It positively correlated with soil penetration resistance at the depth of 20–40 cm, the proportion of 0.5–7.0 mm aggregates, and soil moisture. It negatively correlated with the proportion of aggregates larger than 7 mm and smaller than 0.25 mm. This component indicated a variation in soil properties that was induced by causes independent of recreational exposure. The extracted gradients of soil properties significantly influenced the abundance of micromollusc populations. The abundance of all species decreased after increase in recreational load. Micromollusc species responded to direct recreational exposure as plateau (C. lubrica) and asymmetric unimodal responses (V. pulchella and A. aculeata)
Phytoindication approach to assessing factors determining the habitat preferences of red deer (Cervus elaphus)
Get PDFThe study examined the possibility of using the phytoindication technique to describe habitat preferences of red deer in a relatively homogeneous area. Two alternative hypotheses were tested. Hypothesis 1 suggests that the relationship between red deer and vegetation is due to a trophic factor, so preferences for individual plant species cause vegetation to influence the distribution of animal numbers. Hypothesis 2 suggests that environmental factors influence vegetation, structuring and determining the productive level of the community as a whole. Therefore, environmental factors, rather than individual plant species, cause vegetation-animal interactions. The research was conducted on Biryuchiy Island Spit, where the Azov-Sivash National Nature Park is located. The geobotanical surveys were performed in three types of ecosystems: sandy steppe (vegetation class Festucetea vaginatae), saline meadows (vegetation class Festuco–Puccinellietea), and artificial forest plantation (vegetation class Robinietea). 250 releves were recorded according to the Brown-Blanquet approach. The number of fecal pellets and the number of groups of pellets of red deer was recorded together with geobotanical surveys in the same sample plots. The pellet groups counted in the field were converted to deer densities in specific vegetation classes taking into account the number of pellet groups on the site and the decay rate of the fecal pellets. The vegetation types were distinguished by the number of deer fecal pellets per unit area. The highest number of fecal pellets was found for the plant class Festucetea vaginatae, somewhat fewer fecal pellets were in the plant class Robinietea, and the lowest number was in the plant class Festuco-Puccinellietea. A geometric distribution model is adequate for explaining the experimental data on the number of fecal pellets. A total of 59 species of flowering plants were found. Based on the species composition and projective cover of species, the ecological regimes of ecotopes were identified by phytoindication. The correspondence analysis of the vegetation revealed two ordination axes. The ordination axis 1 (CA1) was able to explain 11.3% of community inertia, and the ordination axis 2 (CA2) was able to explain 5.2% of community inertia. The maximum excretory activity of animals was recorded for the central part of the ordination space, indicating the presence of an optimum zone in the gradient of environmental factors that structure plant communities. The forward selection procedure allowed the Nutrients Availability variable to be selected as the most important variable to explain variation in the plant community structure. The number of deer fecal pellets exhibited different patterns of response in the Nutrients Availability gradient. The response within the plant class Festucetea vaginatae could best be explained by Model III from the list of HOF-models. The response of the excretory activity of deer within the class Festuco-Puccinellietea could best be fitted by the model IV, which represents a symmetric Gaussian curve. The response of excretory activity in the Robinietea vegetation class was asymmetrical bimodal. The ecological properties of the red deer ecological niche in both the drier and less mineralized part of the range of ecological conditions and the wetter and more mineralized part should be assessed in the context of the prospects for future studies
The phenomenon of the shrinking size of bank vole (Myodes glareolus) in an anthropogenic environment (experience of 50 years of observations)
Get PDFFifty years of continuous monitoring of the bank vole population (Myodes glareolus Schreber, 1780) revealed the phenomenon of shrinking body size of individuals, manifesting in significant reduction in their regular size and mass parameters. Field observations were carried out in the Kaniv Nature Reserve (Cherkasy region, Ukraine) during the first half of summer every year. In the forest biotopes of the reserve, this species is dominant in the group of rodents. The research period covered various stages of the existence of the protected ecosystem. Its small area, location ina densely populated region of Ukraine and interaction with neighboring territories which are involved in economic activities have always caused anthropogenic pressure on the protected area. Its nature and intensity determined the changes in the protection regime and the loss of reserve status in 1951–1968. Later, the territory of the reserve experienced increasing technogenic pressure accompanied by radioactive contamination. In this work, to compare their characteristics, four complete cycles of the density dynamics of the bank vole population (from depression to depression) were selected, the duration of which was 4–5 years. The first three cycles correspond to qualitatively different periods in the existence of the ecosystem and the population of the studied species, and the last one corresponds to the relatively current situation. Over the recent 30 years, the size and mass parameters of individuals of bank voles have deсreased, - this phenomenon was called shrinking. The process was also observed to tend towards consistent increase in scale. Differentiated analysis shows that in different sex and functional groups of animals, the decrease in exterior parameters can reach 30.3%. Shrinking is especially notable in the group of adult females that are actively involved in reproduction (compared to the second cycle, considered as the control, the decrease in parameters among these is 33.2%). Juveniles of this sex lost 31.8% of their fatness. Besides, in the population of voles, the proportion of large-size individuals was significantly reduced. The group of animals that overwintered significantly reduced its representation, and its existing representatives had much smaller exterior parameters. The studies found that the shrinking process is stable over time, which does not allow it to be considered a random phenomenon or an artifact of research. This phenomenon has no correlation with the amount or availability of food. It occurs against the background of numerous changes in various aspects of population dynamics, which gives grounds to associate it with anthropogenic changes in the environment. Shrinking is believed to be realized through various mechanisms. Firstly, as a result of mortality, the largest individuals and reproducing females with the greatest energy needs disappear from the population, and secondly, the growth and weight gain of young animals is slower. As a result, decrease in the size and mass parameters of individuals reduces their specific energy needs and allows the population to bring their requirements in correspondance with the capability of the environment to support a certain number of resource consumers. An analogy was drawn with the Dehnel’s phenomenon, described for shrews of the Sorex genus, whose body size and weight decrease is an element of preparation for experiencing adverse winter conditions. Based on similar concepts, the shrinking of its elements can be considered as a specific population strategy to maintain the ecological balance
Features of Trifolium rubens (Leguminosae) ontomorphogenesis in conditions of Ukraine
Get PDFThe necessary basis for studying the structure and dynamics of populations is an investigation of ontomophogenetic peculiarities and establishment of ontogenetic stages of individuals. Information about ontomorphogenesis is especially important for protected species of plants. The minimal amount of data on morphology of plants in the different periods of ontogenesis complicates plant identification and evaluation of population state conditions in nature and culture. Trifolium rubens L. is a perennial Central European plant listed in the Red Book of Ukraine as a rare species. The objective of this research is to analyze the peculiarities of ontomorphogenesis of T. rubens, to establish diagnostic signs of age stages and the sequence of their passage for identification of the multivariance of development. The results of the study on T. rubens ontomorphogeny at the M. M. Gryshko National Botanical Garden оf the National Academy of Sciences of Ukraine and in the natural population in Zakarpattya are represented in this article. The terms “age stage” and “age period” are used to describe the degree of ontogenetic development of individuals. Diagnostic features of the age periods: latent, pregenerative, generative and senile are established. Detailed morphological descriptions of plants in different stages of ontogenesis are presented. The study shows a multivariate development that reveals different sequences of passing ontogenesis stages by individuals and, accordingly, the rate of their aging and life expectancy. It was found that during the first year of vegetation the plants undergo two periods (latent and pregenerative) and 5 stages of ontogeny (latent, seedlings, juvenile, immature and virginile). The first bloom in plants appears mainly in the second year of vegetation. The research showed the change of the leaf blade shape in ontogeny from simple to compound. There is a difference in the pubescence of leaf parts, and leaf shape indicates that these features are age-old. It was concluded that the aboveground part of the immature, virginile, generative individuals during the flowering period of plants differ from subsenile and senile in shape and number of leaves. In the generative period of ontogeny in dense plantings or in the natural population, it is difficult to reliably determine the boundaries of an individual by the aboveground part. The correlation between vegetative shoots of different type and generative shoots in the individual or group of plants can be used as an indicator to estimate the ontogenetic status of a particular locus or population. Successful growth of T. rubens in culture outside the natural range indicates good prospects for its ex situ protection and the implementation of measures for repatriation and restoration of populations in nature. The data of the research may be used for evaluation of the age structure of T. rubens populations
Phytoindication assessment of the effect of reconstruction on the light regime of an urban park
Get PDFThe ecological restoration of urban parks is used to increase their recreational attractiveness, improve air quality, mitigate urban heat island effects, improve stormwater infiltration, and provide other social and environmental benefits. The dynamics of plant communities after urban forest restoration requires investigation. The study assessed the impact of urban park reconstruction on the state of grass cover, phytoindication of changes in light regime caused by park reconstruction and found out the dependence of reliability of phytoindication assessment on the number of species in the relevant area. The study was conducted in the recreational area of the Botanical Garden of the Oles Honchar Dnipro National University (Ukraine). A tree plantation was created after the Second World War in the location of a natural oak forest. In 2019, a 2.8 ha area of the park was reconstructed. The samples were taken within polygons, two of which were placed in the reconstruction area and two of which were placed in a similar section of the park where no reconstruction was performed. During the reconstruction process, walkways were rebuilt, shrubs were removed, old, damaged trees were removed, and tree crowns were trimmed. Juvenile trees were planted in place of the removed old trees. Old outbuildings, which greatly impaired the aesthetic perception of the park, were also removed. Transport and construction machinery was involved in the reconstruction. A total of 65 plant species were found within the studied polygons. The number of herbaceous species in the park area after reconstruction was higher than without reconstruction. The crown closure in the reconstructed area was significantly lower than that in the untreated conditions. The phytoindication assessment showed that the light regime varies from the conditions suitable for the scyophytes (plants of typical foliage forests) to the conditions suitable for the sub-heliophytes (plants of light forests and shrubberies, or high herbaceous communities; lower layers are in the shade). The light regime in the park area after reconstruction was statistically significantly different from the regime in the untreated park area. The lighting regime after the reconstruction was favourable to sub-heliophytes, and without reconstruction the regime favoured hemi-scyophytes. Tree canopy crown closure negatively correlated with grass height and herbaceous layer projective cover. The tree canopy crown closure, grass height, and herbaceous layer projective cover were able to explain 86% of the phytoindication assessment of the lighting regime variation. These parameters negatively affected the light regime. The prospect of further research is to investigate the dependence of indicative reliability of the assessment of other environmental factors with the help of phytoindication depending on the number of species. In addition to the indication of traditional ecological factors it is of particular interest to clarify the aspect of the dynamics of hemeroby indicators as a result of park reconstruction
Distribution, bioecological peculiarities of staphylinids (Coleoptera, Staphylinidae) in livestock biocenoses of forest-steppe and steppe Ukraine
Get PDFAs a result of research in the territory of livestock farms, 103 species of predatory Coleoptera were found, including Staphylinidae accounting for 51.4%, Histeridae – 27.3%, Carabidae – 21.3%. A total of 39 species of the Staphylinidae family were identified, belonging to 5 subfamilies: Oxytelinae, Steninae, Staphylininae, Tachyporinae, Aleocharinae. Species composition of staphylinids varied in relation to the types of animal rearing premises. In cowsheds and calf pens species diversity was higher (35 species). To study the peculiarities of feeding in laboratory conditions, we monitored 9 species of Staphylinidae: Philonthus addendus Sharp, Ph. cruentatus (Gmel.), Ph. rectangulus Sharp, Ph. varians (Payk.), Ph. spinipes Sharp, Ph. nitidus F., Creophilus maxillosus (L.), Ontholestes murinus (L.), Oxytelus sp. Feeding specialization of imagoes and larvae of different ages was studied. We determined that the mass of food consumed per day is higher than the weight of the beetles. Large species of staphylinids prefer feeding on average-aged larvae of flies and can eat puparia. Peculiarities of the development of coprophilous staphylinids were studied on the example of Ph. spinipes Sharp. During 24 h a female laid 1–3 eggs (in +28°С). Duration of the egg phase depends on the temperature regime (in +20 °С – 4–5, +28 °С – 3–4 days). Cessation of egg laying was observed with decrease in the temperature to +14 °С. The development takes part in three larval stages. Duration of the larva phase at +28 °С was 8–10 days, at +20 °С – 13–14 days. The first moulting was observed on the 2–3th days (in +28 °С) after the larvae emerged from the eggs. At +28 °С the pupa phase lasted 8–10 days. Decrease in temperature prolonged the rate of the development. At +24 °С it practically did not change (9–10 days), at +18 °С – increased to 13–15 days
Biological specifics of exogenous development of Oxyuris equi nematodes (Nematoda, Oxyuridae)
Get PDFHelminths of the species Oxyuris equi Schrank, 1788 are pathogens of domestic and wild odd-toed ungulates. They parasitize in the large intestine of horses, causing colitis and dermatitis at the tail root area. The wide distribution and overall persistence of this species is significally promoted by the specifics of its development and reproduction. Here we studied the specifics of the exogenous development of O. equi nematodes parasitizing Equidae in respect to the factor of temperature and the morphometric changes in oxyuris eggs at different stages of embryogenesis. In laboratory culture of O. equi eggs obtained from female gonads, the embryogenesis occurs in four stages: morula, formation of bean-like embryo, formation of non-invasive larva and formation of infectious larva. The stages of development differ by the morphological parameters. It is established that the development of O. equi eggs is directly related to temperature. The optimal temperature for embryogenesis is 25 °С, at which the highest survival rate of infectious eggs, 81.3%, was observed. At 20 °С and 15 °С the survival of eggs decreased during culturing and the ratios of infectious eggs were 75.7% and 67.3%, respectively. Accordingly, 24.3% and 32.7% of eggs died during development. The temperature also affects the duration of development of O. equi eggs. At 25 °С, the development of Oxyuris eggs was the fastest and occurred in two days. With temperature falling to 20 and 15 °С, the duration of egg development slowed to three and five days, respectively. The process of embryogenesis in Oxyuris is associated with changes in metrical parameters. The length, width and area of egg surface increased. Length and width of egg plug, and shell width of mature Oxyuris eggs decreased. The obtained data on the duration and specifics of exogenous development of parasitic O. equi nematodes will allow effective control measures for horse oxyurosis to be developed