Subjective Mobility after 1989: Do People Feel a Social and Economic Improvement or Relative Deprivation?

Subjective judgments of social & economic mobility in Hungary, Bulgaria, Poland, Russia, Slovakia, & the Czech Republic are investigated in an analysis of data gathered by the international comparative study, Social Stratification in Eastern Europe after 1989. It is found that in all 6 countries, a sense of improved social position is correlated with social characteristics such as a lower age group & higher level education & profession, while a sense of declining social position is linked with the inverse of these characteristics. However, the sense of social deprivation does seem to be less in the Czech Republic than in other countries; factors contributing to this are identified

Discovery of a Pederin Family Compound in a Nonsymbiotic Bloom-Forming Cyanobacterium

The pederin family includes a number of bioactive compounds isolated from symbiotic organisms of diverse evolutionary origin. Pederin is linked to beetle-induced dermatitis in humans, and pederin family members possess potent antitumor activity caused by selective inhibition of the eukaryotic ribosome. Their biosynthesis is accomplished by a polyketide/nonribosomal peptide synthetase machinery employing an unusual trans-acyltransferase mechanism. Here, we report a novel pederin type compound, cusperin, from the free-living cyanobacterium Cuspidothrix issatschenkoi (earlier Aphanizomenon). The chemical structure of cusperin is similar to that of nosperin recently isolated from the lichen cyanobiont Nostoc sharing the tehrahydropyran moiety and major part of the linear backbone. However, the cusperin molecule is extended by a glycine residue and lacks one hydroxyl substituent. Pederins were previously thought to be exclusive to symbiotic relationships. However, C. issatschenkoi is a nonsymbiotic planktonic organism and a frequent component of toxic water blooms. Cusperin is devoid of the cytotoxic activity reported for other pederin family members. Hence, our findings raise questions about the role of pederin analogues in cyanobacteria and broaden the knowledge of ecological distribution of this group of polyketides.Peer reviewe

Microbial Architects of the Cold Deserts: A Comprehensive Research of Biological Soil Crusts in the High-Altitudinal Cold Deserts of the Western Himalayas

Our research has focused on Biological Soil Crusts (BSCs) in the Western Himalayas, specifically in Tibetan Plateau and Karakoram (Ladakh, India) along the elevation gradient spanning a range of 4300–6000 m a.s.l. where habitats like cold deserts, steppes, alpine and subnival vegetation, as well as primary successional stages behind retreating glaciers are present. These regions are characterised by extensive development of BSCs, with cyanobacteria as the dominant component. BSCs are of great significance for the sustainability and development of ecosystems of arid regions worldwide. Their activity is limited to brief periods when precipitation or dew hydrates microbial cells, enabling metabolic activity. Despite the crucial role played by these phototrophic microbial communities in arid and semi-arid ecosystems worldwide, remote mountain regions like the Tibetian Tibetan Plateau and Karakoram have received limited attention in this regard. More than 15 years long research allowed us to determine several critical aspects of BSCs’ activity and performance:We conducted laboratory and in-situ experiments Fig. 1 to assess the potential photosynthetic and heterotrophic activity of BSCs from high-altitude cold deserts. The experiments involved measuring the production and consumption of CO2 and O2 by BSCs under various temperature and moisture conditions, as well as light intensity. By manipulating these factors, we could differentiate the activities of heterotrophs and autotrophs within the BSCs. The results of these experiments were then analysed in the context of soil nutrient stoichiometry, phylogenetic structure, and microbial community biomass. Using these data, we developed a mechanistic mathematical model to predict the overall metabolic activity of BSCs in response to the major climatic drivers: temperature and moisture. This knowledge could help us to predict the reaction of BSC to climatic changes and reveal if the arid areas in Western Himalayas will act as CO2 sources or sink.We further investigated the composition and content of pigments in microbial soil communities across various habitats along the elevation gradient in the Tibetan Plateau (Rehakova and Capkova 2019). Soil microbes have evolved complex metabolic strategies, such as producing photoprotective and photosynthetic pigments, to survive the environmental stress caused by high UV radiation, fluctuating temperatures, and drought.We also examined the effects of environmental factors such as altitude, mountain range, and soil physico-chemical parameters on the composition and biovolume of phototrophs which dominate the BSc in the studied region (Řeháková 2011, Janatková and Řeháková 2013). This was accomplished through multivariate redundancy analysis and variance partitioning. Interestingly, the phylogenetic diversity and morphotypes’ composition were similar between the Karakoram and Tibetan Plateau (Čapková 2015). Our investigation represents the first recorded assessment of the phylogenetic diversity of cyanobacterial communities within biological soil crusts in the Western Himalayas, specifically at altitudes exceeding 5000 m

Seasonal variation of gross ecosystem productivity of periphyton in three post-mining lakes in the Czech Republic, Europe

We investigated the seasonal variation of gross ecosystem productivity (GEP) of periphyton biomass in three post-mining lakes in the Czech Republic. These lakes were established as part of recultivation efforts after coal mining activities and resulted in a unique series of anthropogenic oligotrophic lakes of gradual successional age. Periphyton is ubiquitous in aquatic habitats and performs numerous environmental functions such as nutrient cycling and self-purifying of aquatic ecosystems. Well-developed periphyton mat can be formed within a few weeks, so it can quickly become the dominant of littoral zone of newly established lakes. In studied post-mining lakes, the highly developed periphytic community covers the littoral zone of each lake to the depth of 2m (Bešta et al. 2022, Konopáčová et al. 2023) Fig. 1.We aimed to shed some new light on the processes controlling the dynamics of primary productivity in oligotrophic lakes. The accurate estimation of primary productivity is crucial for understanding the functioning of aquatic ecosystems, as primary productivity serves as the primary source of autochthonous carbon in these systems. In addition to phytoplankton, periphyton can significantly contribute to primary productivity in littoral zones, known for their high productivity and biodiversity. Conducting in situ measurements provides the most accurate means of inferring the metabolic activity of primary producers in littoral zones.We conducted detailed seasonal in-situ periphyton gross primary production (GPP) measurements in three post-mining lakes with different successional ages (Čapková et al. 2022).  GPP and NPP of periphytic biomass were determined using direct in-situ measurement of O2 fluxes. O2 production and consumption were measured over 5 hours of in-situ light and dark gas-tight glass bottle incubation. Bottles were filled with the lake water from the corresponding depth, and a similar amount of periphytic biomass was enclosed Fig. 2. We used the Fibox3 fibre-optic oxygen meter coupled with a PSt3 oxygen sensor (PreSens, Regensburg, DE) to measure changes in O2 concentration. The O2 fluxes were normalized to periphytic biomass in each bottle (measured as total organic carbon). Data were corrected for O2 concentration changes in dark and light gas-tight bottles containing lake water without periphytic communities.This setup enabled us to monitor online oxygen flux, therefore, insights into metabolic activities. The primary productivity was measured in real-time, allowing us to capture the quantitative effect of various environmental drivers on periphyton productivity, i.e. phosphorus concentration and light intensity, as they are known to play significant roles in primary productivity.We showed that the primary production of periphyton mats exhibited seasonal variations, with higher productivity observed in spring compared to other seasons. This observation could be attributed to the occurrence of winter/spring upwelling events and vertical mixing, which resupply nutrients from the deeper strata. Furthermore, the physiological activity of periphyton was strongly influenced by the seasonal changes in light intensity, temperature, and nutrient concentration.We provided the first insight into the seasonal variation of primary productivity of the periphyton assemblage dominating the littoral zone of newly established post-mining lakes. We stress the importance of periphyton in aquatic ecosystems, particularly in anthropogenic oligotrophic lakes

Unveiling the ecological significance of algal mats and meadows: Insights into phosphorus cycling and primary production of benthic algae in post-mining lakes

Post-mining lakes are anthropogenic water bodies increasing globally due to mining suppression and recultivation. These lakes have ecological and socioeconomic significance, providing freshwater sources, wildlife habitats, and recreation potential. However, research on primary producers in these lakes is limited, with most studies focusing on phytoplankton while neglecting algal mats and meadows. If developed in high biomass, algal mats and macroalgal meadows play a crucial role in aquatic ecosystems. They contribute to the trophic structure, nutrient fluxes, primary production and to the purification of entire waterbodies. Yet, there is a lack of knowledge regarding the nutrient acquisition and the contribution of algal mats and meadows to total primary production and phosphorus (P) cycling, especially in oligotrophic lakes, including post-mining lakes. Our team investigates the benthic algal primary producers - algal mats and meadows in the littoral zone of tree newly established post-mining lakes located in the Czech Republic (Europe). Our main objectives are to describe the quality and quantity of primary producers, quantify the contribution of algal mats and meadows to the primary production and phosphorus cycling in the oligotrophic post-mining lakes. We have studied them throughout all seasons with a special focus on the generally neglected winter/spring season. Our sampling strategy encompasses three gradients of variability along which the composition and ecological role of benthic algae change:spatial variability along the depth gradient within each lake,itemporal variability throughout the seasons within each lake and successional variability between the lakes of different age.The methodological approach consists of measuring the limnological and chemical parameters of lakes, taxonomic determination, biomass estimation and C:N:P stoichiometry of algal biomass along the whole gradient of the euphotic zone (0-15m). The in situ measurement of primary production of benthic algae from various depths using the oxygen meter Fibox 3 (PreSens, Germany) with a combination of laboratory experiments was employed too (Čapková 2022). We measure the kinetic parameters of P uptake of algal mats and meadows using 33P-labelled orthophosphates under controlled conditions similar to the nature (Konopáčová 2021). According to our survey, algal mats and meadows exhibited high productivity in the entire littoral zone. Algal mats dominate the depth up to 3m Fig. 1 and are highly diverse, with more than 400 identified taxa (Bešta 2022). Macroalgal meadows formed by the genus Chara together with the genus Vaucheria, are key taxa occupying the deeper zone (3-15m) Fig. 2. The distribution of benthic algae in lakes is influenced by depth gradients, substrate quality, seasonality and age of lakes foundation, resulting in complex spatio-temporal patterns. Specific emphasis is placed on the fate of P, which is the limiting nutrient in investigated lakes. High C:P molar ratios in microalgal mats indicate strong P deficiency in studied lakes. Over the vegetation season, microalgal biomass doubled, while the P content in biomass dropped to 60% of the values from the start of the vegetation season. The maximum uptake velocity and specific P uptake affinity decreased by an order of magnitude from April to October, and P uptake affinity was measured for comparison in plankton too. Based on our results, we proposed a possible mechanism underlying a stable coexistence of planktonic and benthic primary producers, with plankton prospering primarily in summer and autumn and algal mats and meadows in winter and spring seasons. By integrating data collected during five years of investigation, our study aims to provide a comprehensive understanding of the ecological roles of primary producers in post-mining lakes

Data from: Sink limitation of plant growth determines treeline in the arid Himalayas

1. Understanding what determines the high elevation limits of trees is crucial for predicting how treelines may shift in response to climate change. Treeline formation is commonly explained by a low-temperature restriction of meristematic activity (sink limitation) rather than carbon assimilation (source limitation). In arid mountains, however, trees face simultaneously low temperature and drought, both potentially restricting their growth and thus setting range limits. However, the mechanisms of treeline formation in high arid mountains are largely unknown. 2. We studied Myricaria elegans, one of the world’s highest growing winter-deciduous woody species, endemic to the arid Himalayas. We hypothesized that the upper elevation limit of Myricaria is associated with low-temperatures during the early growing season affecting earlywood formation, while later in the season drought is constraining earlywood maturation and latewood formation. 3. To test this hypothesis, we studied the quantitative anatomy of tree rings at different developmental stages across the entire species elevation range (3200-4400 m). We also explored daily stem increment and rehydration rates, seasonal dynamics of non-structural carbohydrates and stable C isotopes as a proxy for possible drought constraints. 4. Both earlywood and latewood increments decreased towards the treeline, while NSC in leaves, twigs and stem sapwood did not change, indicating a sink limitation as a main driver of the treeline. At treeline, low temperatures restricted earlywood formation more than latewood formation. Treeline individuals had – compared to individuals from lower elevations – smaller and fewer earlywood vessels, frequent frost rings and shorter periods with positive daily increments, but comparable night-time stem rehydration rates and latewood density. All these results suggest a sink limitation as a main mechanism behind the treeline formation in high arid mountains. 5. In the arid Himalayas, the treeline is set by the drastic growth reduction (sink limitation) caused by low temperature and short growing season under otherwise sufficient carbon and water supply. Spring freezing and high summer temperatures further constrain stem increment at treeline. The mean 6.9 °C temperature during the growing season places the Myricaria treeline within the thermal range of other high elevation treelines worldwide and support a common mechanism of alpine treeline formation

Dolezal_Func.Ecology_Data

The file provides data on Myricaria elegans radial stem growth, stem sapwood, branch and leaf non-structural carbohydrates and leaf nutrient concentrations from different elevations in Ladakh, NW Himalayas, India

Seasonal Relationships of Alpine Plants and Microbes through a Stoichiometric and Enzymatic Lens

Alpine biomes experience harsh environmental conditions and short growing seasons, which necessitate interspecific and intraspecific interactions to ensure the stability of diversity and ecosystem multifunctionality. The relationship between plants and microbes in this environment is equally dynamic, with seasonal pulses of nutrients and the phenology of plants creating specific "hot moments" of biogeochemical activity. As a crucial zone of interaction between plant roots and microbial communities, the rhizosphere serves as a "hot spot" of biogeochemical cycling where the mineralization of nutrients, such as carbon, nitrogen, and phosphorus, allows for the transfer of nutrients between trophic levels. However, the nature of these interactions depends on edaphic and climatic conditions, potentially leading to cooperation or competition to meet the stoichiometric demands of organisms.Elevation gradients within alpine ecosystems provide dramatic shifts in temperature, precipitation, and soil development that allow for the study of these interactions over short geographical distances. In conjunction with seasonal sampling, this approach can provide a wide environmental context to observe the relationship between specific plants and microbial communities. By investigating the C/N ratios of plants, microbes, and soil, as well as microbial enzymatic potential, we can infer nutrient limitations, temporal niche partitioning, and biological responses to abiotic conditions.Within the Austrian Alps, we studied a selection of herbaceous plants and their associated microbial communities across an elevation gradient spanning 2200-2800 m (Fig. 1). The primary aims of the study were to assess the seasonal changes in C/N stoichiometry from both trophic levels, microbial enzymatic potential, and rhizosphere diversity of bacterial and fungal communities. To fulfill these aims, four locations were selected based on the two present biomes (alpine meadow and sub-nival zone) and the transition between them. Four to five plant species were collected during each season in 2023, including the often-neglected snow-covered winter season, along with rhizosphere and bulk soil for microbial biomass measurements and soil chemistry. Plant leaf tissue samples were analyzed using Isotope-ratio mass spectrometry for plant C/N ratios, while soil and microbial C/N ratios were calculated using chloroform fumigation extraction. Microbial enzymatic potential was assessed using hydrolase enzymatic assays for five fluorophore-labeled substrates. 16S-rRNA and 18S-rRNA genes were sequenced using an Illumina MiSeq platform from the fine roots of collected plant individuals to quantify the relative abundances of bacterial and fungal taxa.The findings of our study indicate that the higher microbial biomass (Cmic) in alpine meadow locations leads to increased enzymatic activity compared to sub-nival zones. However, specific plant species were found to enhance microbial biomass and enzymatic potential in different seasons, suggesting that plants promote microbial interaction and biogeochemical cycling during different seasons as a form of temporal niche partitioning. Most plant species demonstrated an increase in C/N ratios throughout the season, sometimes increasing by more than 200%. However, two Poa spp. showed the highest C/N ratios during the summer, which further correlated with higher microbial C/N ratios.By observing changes in stoichiometric ratios of organisms that interact and share nutrients, we propose that these relationships vary between host plants depending on their temporal niche and abiotic factors (soil and environmental conditions). Furthermore, the positive or negative correlation of plant and microbial C/N ratios may indicate the relative cooperation or competition between trophic levels