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Late Glacial and Early Holocene climate dynamics in the southeastern Baltic region based on Chironomidae data.
No full textThis paper examines the environmental and climatic changes during Late Glacial and Early Holocene, based on Chironomidae data from Čepkeliai bog and Lieporiai paleoalake sediment section situated in Lithuania and Velykoye Lake sediment section situated in Belarus. Chironomidae data were correlated with the paleobotanical, isotopic, lithological, geochemical investigation results. This study enables to collect data about Chironomidae morphotype evolutional changes during the Late Glacial and Early Holocene in Lithuania and Belarus. The chironomids were distinguished from different chronozones and compared with contemporaneous data from European countries. The palaeoclimatic reconstructions carried out enabled to reconstruct the change in the mean July temperature during the Late Glacial and Early Holocene and to identify a series of postglacial climatic events
Worldwide diversity of endophytic fungi and insects associated with dormant tree twigs /
No full textInternational trade in plants and climate change are two of the main factors causing damaging tree pests (i.e. fungi and insects) to spread into new areas. To mitigate these risks, a large-scale assessment of tree-associated fungi and insects is needed. We present records of endophytic fungi and insects in twigs of 17 angiosperm and gymnosperm genera, from 51 locations in 32 countries worldwide. Endophytic fungi were characterized by high-throughput sequencing of 352 samples from 145 tree species in 28 countries. Insects were reared from 227 samples of 109 tree species in 18 countries and sorted into taxonomic orders and feeding guilds. Herbivorous insects were grouped into morphospecies and were identified using molecular and morphological approaches. This dataset reveals the diversity of tree-associated taxa, as it contains 12,721 fungal Amplicon Sequence Variants and 208 herbivorous insect morphospecies, sampled across broad geographic and climatic gradients and for many tree species. This dataset will facilitate applied and fundamental studies on the distribution of fungal endophytes and insects in trees
Cyanophage distribution across European lakes of the temperate-humid continental climate zone assessed using PCR-based genetic markers /
No full textStudies of the diversity and distribution of freshwater cyanophages are generally limited to the small geographical areas, in many cases including only one or few lakes. Data from dozens of various lakes distributed at a larger distance are necessary to understand their spatial distribution and sensitivity to biotic and abiotic factors. Thus, the objective of this study was to analyze the diversity and distribution of cyanophages within the infected cells using marker genes (psbA, nblA, and g91) in 21 Polish and Lithuanian lakes. Physicochemical factors that might be related to them were also analyzed. The results demonstrated that genetic markers representing cyanophages were observed in most lakes studied. The frequently detected gene was psbA with 88% of cyanophage-positive samples, while nblA and g91 were found in approximately 50% of lakes. The DNA sequence analyses for each gene demonstrated low variability between them, although the psbA sequences branched within the larger cluster of marine Synechoccocuss counterparts. The principal component analysis allowed to identify significant variation between the lakes that presented high and low cyanobacterial biomass. The lakes with high cyanobacterial biomass were further separated by country and the different diversity of cyanobacteria species, particularly Planktothrix agardhii, was dominant in the Polish lakes and Planktolyngbya limnetica in the Lithuanian lakes. The total phosphorous and the presence of cyanophage genes psbA and nblA were the most important factors that allowed differentiation for the Polish lakes, while the pH and the genes g91 and nblA for the Lithuanian lakes
A review on detection techniques, health hazards and human health risk assessment of arsenic pollution in soil and groundwater /
No full textOne of the most significant elements in the environment is arsenic (As). It is a hazardous metalloid that causes contamination of soil and water supplies as a result of numerous anthropogenic and natural sources. This pollution has detrimental impacts on human health and the ecosystem, making it crucial to monitor and control. The release of As from minerals into the soil and groundwater depends on the kind of mineral, pH, and redox conditions. As is typically found in two forms, trivalent arsenic (As3+, arsenite) and pentavalent arsenic (As5+, arsenate), both of which are inorganic and extremely deadly. When it comes to toxicity, arsenite is more dangerous than arsenate. Many people have been affected by As poisoning, due to exposure to As through water and food. Nowadays, accurate, fast measurement of As in the field remains a technical challenge; however, the X‐ray fluorescence method is considered the most reliable, cost effective and capable of measuring a wide spectrum of metals. Health risk assessment is a crucial parameter to estimate the health hazards of the As molecule. The risk assessment approach proposed by the USEPA is common and widely used, amongst others. On the numerous health risk assessment models/ frameworks used to foresee the carcinogenic and non‐carcinogenic health impacts brought on by As‐contaminated water, little information is currently accessible. This discussion also emphasizes the need for more study on the risks to human health posed by specific As species (both organic and inorganic) found in As‐contaminated water
Association of ScV-LA virus with host protein metabolism determined by proteomics analysis and cognate RNA sequencing /
No full textSaccharomyces yeasts are highly dispersed in the environment and microbiota of higher organisms. The yeast killing phenotype, encoded by the viral system, was discovered to be a significant property for host survival. Minor alterations in transcription patterns underpin the reciprocal relationship between LA and M viruses and their hosts, suggesting the fine-tuning of the transcriptional landscape. To uncover the principal targets of both viruses, we performed proteomics analysis of virus-enriched subsets of host proteins in virus type-specific manner. The essential pathways of protein metabolism–from biosynthesis and folding to degradation–were found substantially enriched in virus-linked subsets. The fractionation of viruses allowed separation of virus-linked host RNAs, investigated by high-content RNA sequencing. Ribosomal RNA was found to be inherently associated with LA-lus virus, along with other RNAs essential for ribosome biogenesis. This study provides a unique portrayal of yeast virions through the characterization of the associated proteome and cognate RNAs, and offers a background for understanding ScV-LA viral infection persistency
Retų ir saugomų vabalų, priklausančių nuo brandžių lapuočių medžių, tyrimas naudojant kvapų gaudykles.
No full textSoil water and stable isotopes in the unsaturated zone profile - field observations and analysis /
No full textIn this review, we provide research data emphasizing the role of groundwater table and hydrom- eteorological parameters variation on soil water fluctuations in the unsaturated soil profile. We focused on soil water content, air temperature, precipitation and groundwater table observations. The ThetaProbe Soil Water Sensors basing on changes in the apparent dielectric constant were used for soil volumetric water con- tent measurements. The sensors were installed at the different depths of the unsaturated zone profile under natural atmospheric conditions. The observations lasted more than five years (14 November 2013 - 31 De- cember 2018). Groundwater table data was obtained using Diver data loggers, which continuously recorded water pressure and temperature. For more detailed investigations of water and mass transport at the Maisiagala radioactive waste repository site water, stable isotopes as environmental tracers were used as well
Effect of organic matter fertilizers on the composition of volatiles, morphometrical and anatomical parameters of essential oil-bearing Thymus x citriodorus cultivated in an open field conditions /
No full textThymus x citriodorus (Lamiaceae) is medicinal, essential oil-bearing hybrid, synthesizing significant amounts of geraniol. This hybrid is suitable for cultivation in an open ground in the Baltic region; therefore, increasing the yield and amounts of bioactive compounds by organic matter fertilization during organic farming is realized. The aim of the present study was to evaluate the effect of fertilization with liquid cattle dung and humus on the quantitative and qualitative composition of essential oils as well as on biomass for some morphometrical and anatomical parameters of Thymus x citriodorus that were grown in open ground for two years. Each fertilization treatment was carried out on four replications, and four separate experimental plots were used as control plots. For anatomical investigations, the impress method and light microscopy were used. The essential oils were isolated by hydrodistillation and analyzed by GC-FID and GC-MS. The results showed somewhat different effects of liquid cattle dung and humus on the investigated parameters of hybrid in the first (warmer and drier) and second (rainier and cooler) experimental years. Liquid cattle dung had positive effects on biomass, height and the area covered by plants and on the number and length of inflorescences as well as on the density of stomata in the lower epidermis in the first year, but in the second experimental year, effects were observed on the length of inflorescences only. The effect of humus on the density of glandular trichomes in the upper epidermis of leaves was positive in the first year, but negative in the second experimental year. Moreover, in the second experimental year, humus affected negatively the height of plants and the percentage of the essential oil. The conclusion was that although it is fertilized with the same organic fertilizers, different climatic conditions in different years can influence chemical, anatomical and morphometrical parameters of plants growing in an open ground
Cyanophage infections reduce photosynthetic activity and expression of CO2 fixation genes in the freshwater bloom-forming cyanobacterium Aphanizomenon flos-aquae /
No full textCyanobacteria play a significant role in ecosystem functioning as photosynthetic and CO2 fixing microorganisms. Whether and to what extent cyanophages alter these carbon and energy cycles in their cyanobacterial hosts is still poorly understood. In this study, we investigated changes in photosynthetic activity (PSII), expression of genes associated with the light phase of photosynthesis (psbA, petA, ndhK) and carbon metabolism (rbcL, zwf) as well as intracellular ATP and NADHP concentrations in freshwater bloom-forming filamentous cyanobacterium Aphanizomenon flos-aquae infected by cyanophage vB_AphaS-CL131. We found that PSII activity and expression level of rbcL genes, indicating potential for CO2 fixation, had decreased in response to cyanophage adsorption and DNA injection. During the period of viral DNA replication and assembly, PSII performance and gene expression remained at this decreased level and did not change significantly, indicating lack of transcriptional shutdown by the cyanophage. Combined, these observations suggest that although there is little to no interference between cyanophage DNA replication, host transcription and cellular metabolism, A. flos-aquae underwent a physiological state-shift toward lower efficiency of carbon and energy cycling. This further suggest potential cascading effect for co-occurring non-infected members of the microbial community
Diversity of small mammal parasites and factors shaping their communities.
No full textThe main objective of the dissertation was to investigate the diversity of small mammal blood protozoans and ectoparasites, as well as to evaluate the influence of host, environment and co-infection factors on blood protozoan, gastrointestinal helminth and ectoparasite communities. During the research, we investigated the diversity of blood protozoans and ectoparasites, evaluated host specificity and ectoparasite dominance. Six ectoparasite and two blood protozoan species, as well as protozoans of one genus not identified to species were registered in Lithuania for the first time. The prevalence and mean intensity of parasites of thirteen orders significantly differed among host species and among habitats. Significant differences in seasonal dynamics were recorded for parasites of seven orders. Climatic conditions influenced seasonal dynamics of parasites of six orders. Non-random co-occurrence patterns (positive and negative) were registered among parasites of all orders. A comprehensive analysis of multiple host, environment, and co-infection factors was performed for the first time. Parasites of different orders were affected by two to eight factors (from 18 possible). Host species, habitat, and air temperature influenced parasite communities the most often