Features of the population and genetic structure of Norway spruce (Picea abies (L.) Karst.) from the Ukrainian Carpathian Mountains and Polesie

Genetic differences between a lowland, island, and sparse population (2 ha) of Norway spruce (Picea abies (L.) Karst.) from Polesie and two populations at different altitudes in the Ukrainian Carpathian Mountains (in the range 1000–1500 m above sea level) are identified on the basis of an analysis of the variability of 20 allozyme loci. Despite the different sizes of the samples, different altitude location, and geographic remoteness, these populations are characterized by very low genetic differentiation (D _N = 0.002–0.005). Recombination variability analysis demonstrated that, in terms of the structure of double-locus genotypes, the Polesie population possesses lesser affinity than do the individual Carpathian populations with respect to each other.     

Allozyme Polymorphism of Swiss Stone Pine <Emphasis Type="Italic">Pinus cembra</Emphasis> L. in Mountain Populations of the Alps and the Eastern Carpathians

Swiss stone pine Pinus cembra L. is a species with fragmented range, occurring in the Alpine-East Carpathian mountain system. Seeds of P. cembra are dispersed by nutcrackers, which offers potential possibilities for gene exchange among populations. Using isozyme analysis, we have examined five samples from two parts of the Swiss stone pine range: the Alps (Switzerland and Austria) and the Carpathians (two samples from the northern macroslope of the Gorgany Ridge, Eastern Carpathians, Ivano-Frankivs'ka oblast and one sample from Zakarpats'ka oblast of Ukraine). The allele frequencies of 30 isozyme loci, coding for enzymes ADH, FDH, FEST, GDH, GOT, IDH, LAP, MNR, MDH, PEPCA, 6-PGD, PGI, PGM, SDH, SKDH, SOD, were analyzed using cluster analysis and Principal Component Analysis. Two clusters, corresponding to the isolated Alpine and Carpathian parts of the range, were found. The main contribution to these differences were made by loci Adh-1, Adh-2, Fest-2, Lap-3, Mdh-4, and Sod-4. The interpopulation differentiation proved to be somewhat higher than that typical for pines (F_ST = 7.4%), but within the limits characteristic for taxonomically close species. Thus, isolation of the populations did not lead to their marked differentiation, which may be explained by gene flow and balancing selection, which equalizes gene frequencies across the fragmented species area. Interlocus (F_ST heterogeneity (from 0.003 to 0.173) suggests adaptive significance of some of the allozyme polymorphisms or linkage of some loci with adaptive genes. The Carpathian populations were shown to have higher gene diversity than the Alpine ones (expected heterozygosities 0.095–0.114 and 0.060–0.080, respectively). A deficiency of heterozygotes (as compared to the Hardy-Weinberg proportions), observed in the embryo sample, was probably explained by inbreeding. The reduction in the area of Carpathian pine forests in Holocene, caused by the global climatic changes and the anthropogenic impact, is hazardous for the gene pool of the species. The maintenance of genetic uniqueness of both Carpathian populations of P. cembra in general, and individual stands in particular, requires special measures for protection of Swiss stone pine in the Eastern Carpathians.     

Seasonal changes in the growth rate of duckweed community (Lemnetum gibbae)

Seasonal changes in the growth rate of duckweeds—Lemna minor L. andL. gibba L. associated in the communityLemnetum gibbae (W. Koch 1954)Miyawaki etTx. 1960—were investigated at the Podzámecký fishpond at Pr?honice near Praha, during the growing season of 1969. Initial and final dry weight values (W ₁ andW ₂) of selected samples of the duckweed community were assessed at weekly intervals. The relative growth rate (RGR) was calculated from the dry weight increments, and correlated with water temperature, mean air temperature and sunshine duration. A linear regression equation was fitted to describe the dependence ofRGR on these factors.     

Microbial community changes during a toxic cyanobacterial bloom in an alkaline Hungarian lake

The Carpathian Basin is a lowland plain located mainly in Hungary. Due to the nature of the bedrock, alluvial deposits, and a bowl shape, many lakes and ponds of the area are characterized by high alkalinity. In this study, we characterized temporal changes in eukaryal and bacterial community dynamics with high throughput sequencing and relate the changes to environmental conditions in Lake Velence located in Fejér county, Hungary. The sampled Lake Velence microbial populations (algal and bacterial) were analyzed to identify potential correlations with other community members and environmental parameters at six timepoints over 6 weeks in the Spring of 2012. Correlations between community members suggest a positive relationship between certain algal and bacterial populations (e.g. Chlamydomondaceae with Actinobacteria and Acidobacteria), while other correlations allude to changes in these relationships over time. During the study, high nitrogen availability may have favored non-nitrogen fixing cyanobacteria, such as the toxin-producing Microcystis aeruginosa, and the eutrophic effect may have been exacerbated by high phosphorus availability as well as the high calcium and magnesium content of the Carpathian Basin bedrock, potentially fostering exopolymer production and cell aggregation. Cyanobacterial bloom formation could have a negative environmental impact on other community members and potentially affect overall water quality as well as recreational activities. To our knowledge, this is the first prediction for relationships between photoautotrophic eukaryotes and bacteria from an alkaline, Hungarian lake.     

Festucion carpaticae alliancia nova—a new alliance of tall grasslands in the high Carpathian Mountains

For tall grasslands of Carpathian avalanche troughs with dominantFestuca carpatica (orPoa nemoralis subsp.montana) a new alliance ofFestucion carpaticae has been established. AssociationFestucetum carpaticae Domin 1925 has been introduced into the alliance, with some new localities supported by phytocenological relevés. A new subass.senecietosum nemorensis was described from a forest zone. The plant community with dominantFestuca carpatica of the Roumanian Carpathian Mts. has been separated into a new associationSeslerio rigidae-Festucetum carpaticae and further, a new association of the same areaSaxifrago heucherifolii-Poetum montanae is described. Synmorfological, synecological, syntaxonomical and synchorological characteristics of the associations are mentioned.     

The reaction of amino alcohols with active esters: II. Catalysis of the acylation step by metal ions

The reaction of triethanolamine (TEA) with active substrates—p-nitrophenyl esters and cinnamoyl imidazole (CI)—is catalyzed by divalent heavy metal ions. With Hg²⁺, rate enhancements of 100–1000 (depending on the substrate) were observed, the overall rate constants of substrate decomposition thus exceeding those of spontaneous hydrolysis up to 100,000-fold. The predominant active species at low L:M ratio was found to be the Hg-(TEA)₂ complex. The dependence of the reaction rate upon excess of amino alcohol—at constant Hg²⁺ concentration—is attributable to formation of another active complex—Hg-(TEA)₃.The high reactivity of the system is due to the alcoholate group of metal-bound TEA, whose pK has been lowered by the proximity of the metal ion. This labile nucleophilic alcoholate attacks the substrate causing its alcoholysis and forming O-acyl-TEA. The lability of the metal-alcoholate bond can be enhanced by low concentrations of halide ions, thus causing up to 5-fold additional increase in alcoholysis rate. Higher halide ion concentrations cause inhibition, probably due to formation of inactive HgX₂ molecules.Presumably an important role of the metal ion in metalloenzymes is to affect the decrease in the pK value of a reactive group so that it can exhibit activity under physiological conditions.     

Ternary solvent mixtures for improved resolution of hydroxylated metabolites of vitamin D2 and vitamin D3 during high-performance liquid chromatography

This paper reports the development of three new ternary solvent mixtures for the liquid-chromatographic separation of metabolites of vitamin D on microparticulate silica. All solvent systems offer reduced peak tailing and improved resolution of vitamin D compounds, particularly of 24(R),25-(OH)₂D₃, when compared to the commonly used hexane—isopropanol mixture. The new mixtures can be substituted for hexane—isopropanol systems presently used for preparative liquid-chromatographic steps prior to radioimmunoassay or competitive protein-binding assay of 24,25-(OH)₂D and 1,25-(OH)₂D in human plasma. Hexane—isopropanol—methanol (87:10:3) mixtures are recommended where the lipid content of samples is high, whereas hexane—ethanol—chloroform (80:10:10) promises to be a useful mixture for differentiating vitamin D₃ metabolites from their vitamin D₂ analogs. A combination of the two solvent systems permits the separate assay of both 24(R),25-(OH)₂D₃ and 24(R),25-(OH)₂D₂ as well as 1,25-(OH)₂D₃ and 1,25-(OH)₂D₂.     

Community Seasonal Development Enables Late Defoliation Without Loss of Forage Quality in Semi-natural Grasslands

Agri-environmental measures often require postponing of grassland defoliation until summer months. We investigated how this affects agronomic characteristics, i.e., biomass production and forage quality, in species-rich grasslands in the White Carpathian Mountains, Czech Republic. Three distinct grasslands (vegetation alliances Bromion erecti, Cynosurion cristati, Violion caninae) were selected for biomass sampling in three dates: mid-May, early June and end of June. Proportions of individual species from total biomass, biomass production, crude fibre concentration, organic matter digestibility and community functional properties (forage value, leaf dry matter content, specific leaf area) were determined. Dry matter standing biomass at the end of June was highest in Bromion with 3.5 t/ha, followed by Violion with 2.7 t/ha and Cynosurion with 2.3 t/ha. A steep decline in forage quality (increase in crude fibre and decrease in organic matter digestibility) during accumulation of above-ground biomass was recorded in formerly unmanaged Bromion grassland but remarkably not in formerly grazed Cynosurion and Violion grasslands where early spring dominants were partly replaced by later developing species, Agrostis capillaris and Trifolium spp. Abundance-weighted community functional properties were consistent with results obtained from biomass chemical analyses, thus the ‘trait approach’ can be used as a suitable surrogate of costly and labor-intensive laboratory procedures. Finally, we assume that the high degree of community seasonal development in Cynosurion and Violion, indicated here by a new community seasonal development index and by development in community specific leaf area, was accountable for the stabilization of forage quality later in the vegetation season.     

The human LT system. I. Physical-chemical heterogeneity of LT molecules released by mitogen activated human lymphocytes in vitro.

Molecules with LT activity which can be identified in supernatants from PHA stimulated human lymphocytes by lysis of murine L-929 cell in vitro are heterogeneous. They can be separated by MW on sephadex or ultrogel columns into four separate classes: (a) complex (>200,000 daltons); (b) α (70–90,000 d); (c) β (25–50,000 d); and (d) γ (10–20,000 d). The amount of activity in a supernatant due to each class varies but is approximately: Cx—5 to 20%, α—40 to 60%, β—20 to 40%, and γ—0 to 10%. These classes differ one from another in their stability and kinetics of appearance in culture. Furthermore, they may aggregate together with the complex class under conditions of low ionic strength. Each class, except γ, can be further separated into subclasses by ion exchange chromatography and polyacrylamide gel electrophoresis. Alpha class can be separated on DEAE into the three subclasses, termed, α₁ (rf 0.25), α₂ (rf 0.37), and α₃ (rf 0.50). Alpha₂ subclasses can be further separated on phosphocellulose at pH 6.6 into α_2a (rf 0.37) and α_2b (rf 0.30). However, α₂ contains additional subclasses, which were resolved on PC columns at pH 5.5. Beta class activity can be resolved by DEAE and PAGE into two subclasses, termed β₁ (rf 0.28) and β₂ (rf 0.49). Gamma class activity was not studied, because of its instability. The complex class of LT activity is a macromolecular aggregate greater than 200,000 daltons which appears to contain smaller MW LT class(es). This study demonstrates that materials with LT activity in supernatants from PHA activated human lymphocytes in vitro are very heterogeneous.     

Phytosociological affiliation of Annex II species Tephroseris longifolia subsp. moravica in comparison with two related Tephroseris species with overlapping distribution

The phytosociological affiliation of Tephroseris longifolia subsp. moravica, species of European importance, was studied in relation to two closely related species of the genus Tephroseris which have overlapping distribution within the Western Carpathian Mts: T. intergrifolia and T. crispa. The main aim was to compare plant communities inhabited by the three taxa, to assess the major environmental gradients responsible for variation in their distribution and to estimate ecological indicator values for Tephroseris longifolia subsp. moravica. T. longifolia subsp. moravica was recorded in nine localities in the Slovakia and Czech Republic where it occurs in very specific site conditions of ecotone habitats. Its phytosociological affiliation is restricted to grasslands of the alliances Bromion erecti and Arrhenatherion elatioris and to the ecotone vegetation between these grasslands and beech forests. T. integrifolia occurs most frequently in the Diantho lumnitzeri-Seslerion, Bromion erecti and Quercion pubescenti-petraeae alliances. T. crispa occurs predominantly in communities of the Calthion palustris alliance and Scheuchzerio-Caricetea fuscae, Mulgedio-Aconitetea and Montio-Cardaminetea classes. The major gradient responsible for variation in species composition of communities inhabited by the studied taxa was associated with moisture and nutrient content. The vascular plant-based ecological indicator values for Tephroseris longifolia subsp. moravica calculated from phytosociological relevés with its occurrence were set for light — 6, temperature — 5, continentality — 4, moisture — 5, soil reaction — 6 and nutrients — 5. We conclude that the studied taxon has intermediate relationship to the most of the studied factors in comparison with two related species, T. crispa and T. integrifolia.     

Degradation of cellulose by thermophilic bacteria

Degradation of 1—.10% crystalline cellulose and concentration of:free reducing sugars in the medium, were studied during cultivation of a wild coculture of obligately thermphilic bacteria in 3-L fermentors at 60^°C and pH 7.0 under anaerobic conditions. The coculture was composed of five different species ofBacillus and a single cellulolytic species lof Clostridium. The proportion of degraded substrate was inversely proportional to the initial concentration of cellulose. The higher the initial substrate concentration the lower the proportion of its.degradation. Cellulose at 1 — 2 % concentration is best degraded (98 % in:5.d). The fermentation time increases with increasing cellulose concentration, the level of reducing saccharides increases together with the initial rate of substrate degradation. In the presence of 10 %) cellulose the rate of degradation within a period of a 1-d fermentation is close toV, being 0.455 g L^-1 h^-1withK _m of 12.5 g/L. However, during further cultivation (1—3 d) the rate of degradation of 4—10 % cellulose decreases, probably due to the effect of accumulated reducing saccharides whose levels reach 55—60 mg/L.     

云南花椒园中昆虫群落特征的海拔间差异分析

分析了金沙江畔7个不同海拔区域花椒园中昆虫群落特征的动态变化及其与温、湿度变化的关系。结果表明:花椒园中昆虫群落的多样性、均匀度、丰富度、Ss/Si、Sn/Sp指标随海拔升高先增加后减少,而个体数、优势集中性指数则随海拔升高先减少后增加;低海拔(450—750 m)区域花椒园中由于总体温度高、湿度低,较高海拔(1300—1550 m)区域总体温度低、湿度高,均不利昆虫群落多样性、均匀度、丰富度、Ss/Si、Sn/Sp指标的提高和群落的稳定,而中等海拔(750—1300 m)区域的温度、湿度较为适中,昆虫群落的物种数及个体数量均相对较高,昆虫群落多样性、均匀度、丰富度、Ss/Si、Sn/Sp指标也较高,群落较稳定;相反,低海拔、较高海拔区域花椒园中昆虫群落优势集中性指数较高,而中等海拔区域却相对较低。综合分析表明,海拔高度及温湿度对花椒园昆虫群落特征影响较大,而海拔高度及温湿度的测量和分析较为方便。     

Eco-coenotic conditions and structure of Trollius europaeus L. populations in an extrazonal habitat complex (Transylvanian Carpathian foothills)

To estimate the importance of community structure and environmental factors for maintenance and in situ conservation of populations of European Globeflower (Trollius europaeus subsp. europaeus) in four sites (one within a natural reserve) in a low elevation but cool valley of the Transylvanian Carpathian foothills, an inventory of all globeflower individuals was performed and floristic relevés were recorded in different community types (meadow, fen and scrub). As a surrogate for habitat conditions, we used plant species indicator values for light, moisture and nitrogen. Globeflower density is highest in mesic habitats, the ecological optimum estimated (about 6 on Ellenberg's scale) being slightly lower than that indicated for Central Europe (7). The juvenile:fertile plants ratio (J:F) declines with increasing soil moisture. Larger flower production in hygrophilous communities does not result in a higher proportion of juveniles or J:F ratio. Despite the presumed strong competition determined by high species richness in some host communities, the most dynamic population (large proportion of juveniles) was found in mesophilous, mown meadows. A clumped distribution of fertile plants under the open scrub canopy seems to be responsible for the significantly larger number of flowers per individual observed, as compared with the relative amount of flowers produced in the adjacent sward. Irrespective of host community, the juveniles display an aggregated distribution with respect to fertile plants, which is probably related to short-distance dispersal of seeds. Our results reveal the importance of host community species richness and soil moisture for the target population stage structure and reproductive investment.     

Determination of oxidation-reduction potentials by spectropolarimetric titration: application to several iron-sulfur proteins

The oxidation-reduction potential (E₀?') and the stoichiomotry of electron equivalents (n) of several iron—sulfur proteins determined by direct potentiomctric titration in the presence of redox-mediator dyes and monitored by concomitant changes in circular dichroism are reported. The absence of circular dichroism or changes in circular dichroism by the redox mediators undergoing redox transitions forma the operational basis for the spectropolarimetric titration. The applicability of the method was explored by extensive investigations with spinach ferredoxin.The redox potential and stoichiometry values determined by spectropolarimetric titration are: (1) a plant-type (spinach) ferredoxin, E₀?' = —0.423 V, pH-independent in the range 8.0–9.5; n = 1, (2) a ferredoxin from the nonphotosynthetic bacterium, Clostridium pasteurianum, E₀?' = —0.390 V at pH 8.8, $\text{ΔE}\text{Δ}\text{pH}\text{? 30}\text{mV}$ for pH rangc 6.8–8.8; n = 2, (3) a ferredoxin from the photosynthetic bacterium, Chromatium, E₀′ = ?0.489 V at pH 9.0 and 9.5; n = 2, and (4) an iron sulfur protein designated “Protein II” isolated from Azotobactetr vinelandii, E₀? = ?0.225 V at pH 7.0 and 8.0; n, = 1.An automatic-titration method with a continuously recorded titration curve was demonstrated using the azotobacter Protein II. The general applicability of the spectropolarimetric-titration technique to other biological electron carriers and some experimental factors are discussed.     

Loss of genetic diversity in isolated populations of an alpine endemic Pilosella alpicola subsp. ullepitschii: effect of long-term vicariance or long-distance dispersal?

Pilosella alpicola subsp. ullepitschii (Asteraceae) is a strictly allogamous, diploid Carpathian endemic. Its distribution range comprises two areas separated by about 600 km. While in the Western Carpathians (Slovakia and Poland) the taxon occurs in numerous sites, only four localities of man-made origin are known from the Eastern and Southern Carpathians (Romania). We used allozyme markers to test two likely possible scenarios for the origin of this disjunction: long distance dispersal and vicariance. Our data indicate a significant loss of genetic diversity in the isolated Eastern and Southern Carpathian populations in following genetic parameters (averaged per region): percentage of polymorphic loci (38.9% found in the Eastern and Southern Carpathians versus 58.3% in the Western Carpathians), allelic richness (1.4 vs. 1.6), expected heterozygosity (0.134 vs. 0.235), mean number of distinguishable multilocus genotypes (4.3 vs. 10.6) and proportion of distinguishable multilocus genotypes (0.34 vs. 0.68). Higher proportion of homozygous loci found in the Eastern and Southern Carpathian populations might indicate a higher rate of inbreeding due to non-random mating. We assume that these genetically depauperate populations have experienced a very strong genetic bottleneck, probably due to a founder effect. Although our data suggest that the long-distance dispersal model is most likely, more discriminate genetic markers should be used to test this further.     

Vector borne diseases on an urban environment: The effects of heterogeneity and human circulation

We study the effect of human circulation and host/vector heterogeneities on the onset of epidemics of arboviruses. From a meta-population dynamics based on the classical Bailey–Dietz model, we derive a multi-group model under three assumptions: (i) fast host sojourn time-scale; (ii) mosquitoes do not move; (iii) time homogeneity and strong connectivity of human circulation. Within this modelling framework, three different kinds of R₀ appear: (i) the “true” or “global” R₀—derived from the corresponding next generation matrix; (ii) the uniform R₀—obtained if the patches are taken homogeneous; (iii) the local R₀s—obtained if the patches are disconnected. We show that there is relevant epidemiological information associated to all of them. In particular, they can be used to understand the effects of changing the circulation on the value of the global R₀. We also present additional results on the effects on R₀ of different vector control policies, and a simulation with data from the city of Rio de Janeiro, Brazil.     

Spatial variation in host preference in the endangered epiphytic bromeliad Tillandsia carlos-hankii

Although most vascular epiphytes are generalist, some exhibit host preferences. The latter may vary spatiotemporally driven by variation in environmental conditions. However, to our knowledge no previous studies have evaluated this variation. The aim of this study was to analyze variation in host preferences and population structures in the endangered bromeliad Tillandsia carlos-hankii in two pine-oak forests which differ in environmental conditions, tree composition and community structure. Our questions were: i) does Tillandsia carlos-hankii prefer certain host species over others?; ii) does this preference vary between sites?; iii) how does population structure vary between hosts species and sites? The two sites chosen were an east-facing (I_NE) and a west-facing slope (C_NW). The tree community was sampled within an area of 0.1 ha at each site. Preferred host species were identified using two criteria: a) the degree of colonization; and b) the probability of colonization. In addition, population size-structure on each colonized tree was evaluated to compare between sites and host species. The results showed that almost every tree in the community was colonized by this bromeliad. At both sites Quercus rugosa was a preferred host species, while Q. laurina and Mirsyne juergensenii were preferred at I_NE but limiting at C_NW. In turn, Pinus teocote was limiting at both sites. The percentage of small trees that were colonized depended on species identity. Population structures differed between sites and host species. Thus, both host preferences and local population behavior vary spatially given the differential conditions associated with the two sites.     

Cyrtocrinids (Cyrtocrinida,Crinoidea) and other associated crinoids from the Jurassic (Kimmeridgian–Tithonian)–Cretaceous (Berriasian–Barremian) of the Carpathian Foredeep basement (western Ukraine)

Upper Jurassic (Kimmeridgian–Tithonian) and Cretaceous (Berriasian–Barremian) strata of the Ukrainian part of the Carpathian Foredeep basement are rich, at least locally, in crinoid remains. Crinoids belonging to cyrtocrinids (Cyrtocrinida) are represented by whole cups, isolated remains of disarticulated cups, brachial plates and columnals. They are assigned to the following taxa: Cyrtocrinida indet., Eugeniacrinites cf. cariophilites (von Schlotheim), Lonchocrinus sp., Phyllocrinus stellaris Zaręczny, Ascidicrinus pentagonus (Jaekel), Gammarocrinites sp., Psalidocrinus armatus (Zittel), Psalidocrinus sp., and Hemibrachiocrinidae gen. indet. Cyrtocrinids are associated with other stalked (isocrinids, Isocrinida and millericrinids, Millericrinida) and stemless (saccocomids, Roveacrinida) crinoids. Columnals, pluricolumnals, brachial plates, and cirrals of isocrinids are assigned to Balanocrinus sp., Isocrinina fam. et subfam. indet., and columnals of millericrinids to Millericrinida indet. Free-living roveacrinids are assigned to Saccocoma sp. and Crassicoma sp. Knowledge on Jurassic and Cretaceous crinoids formerly described from Ukraine is discussed. Although majority of crinoids described herein seems to be allochthonous, autochthonous forms were also found with certainty in some intervals. These include some cyrtocrinids, which dominate in shallow-water environments of the Ukrainian Carpathian Foredeep basement. Isocrinids are also common in this shallow marine environment, whereas sessile saccocomids are assigned to low-energy, mud-supported bottom, open marine, outer-platform/upper slope, and relatively deep environments.     

Microbial community responses reduce soil carbon loss in Tibetan alpine grasslands under short‐term warming

Changes in labile carbon (LC) pools and microbial communities are the primary factors controlling soil heterotrophic respiration (R_h) in warming experiments. Warming is expected to initially increase R_h but studies show this increase may not be continuous or sustained. Specifically, LC and soil microbiome have been shown to contribute to the effect of extended warming on R_h. However, their relative contribution is unclear and this gap in knowledge causes considerable uncertainty in the prediction of carbon cycle feedbacks to climate change. In this study, we used a two‐step incubation approach to reveal the relative contribution of LC limitation and soil microbial community responses in attenuating the effect that extended warming has on R_h. Soil samples from three Tibetan ecosystems—an alpine meadow (AM), alpine steppe (AS), and desert steppe (DS)—were exposed to a temperature gradient of 5–25°C. After an initial incubation period, soils were processed in one of two methods: (a) soils were sterilized then inoculated with parent soil microbes to assess the LC limitation effects, while controlling for microbial community responses; or (b) soil microbes from the incubations were used to inoculate sterilized parent soils to assess the microbial community effects, while controlling for LC limitation. We found both LC limitation and microbial community responses led to significant declines in R_h by 37% and 30%, respectively, but their relative contributions were ecosystem specific. LC limitation alone caused a greater R_h decrease for DS soils than AMs or ASs. Our study demonstrates that soil carbon loss due to R_h in Tibetan alpine soils—especially in copiotrophic soils—will be weakened by microbial community responses under short‐term warming.     

Common Buzzards wintering strategies as an effect of weather conditions and geographic barriers

AimMigration is a constantly changing adaptation due to the climate condition evolution. The struggle for surviving during harsh winter season is different across Europe, being more complex toward the inner parts of the continent. The current approach explores the Common Buzzard number variation during the cold season and the climatic predictors of birds of prey wintering movements in relation to the possible influences of the Carpathian Mountains, which may act as a geographical barrier providing shelter from cold air outbreak from north and northeast of the continent.LocationRomania (45°N25°E).TaxonBirds of Prey.MethodsWe applied a GLMM to investigate the relation between continental and local climatic factors with the number of Common Buzzard observations in two regions. The first region is located inside the Carpathian Arch and the other one outside, east of this large mountains chain.ResultsThe Common Buzzard numbers wintering Eastern from the Carpathian Mountains are highly influenced by AO (Z = 2.87, p < .05%), while those wintering western are influenced by NAO (Z = 2.17, p < .05%). This is the first proof of separating influences for biodiversity of AO and NAO at continental scale, outlining the influence limit placed over the Eastern Carpathian Mountains.Main conclusionsThe Carpathian Mountains act like a geographic barrier, separating the wintering Common Buzzard populations from both sides of the mountain range. While the high number of individuals in Moldova is related to their eastern and northeastern Europe origins, in Transylvania the large number of individuals observed is related to the more sheltered characteristics of the region attracting individuals from central Europe. Also, since Transylvania region is well sheltered during cold air outbreak, it represents a more favorable region for wintering. From this point of view, we can consider that the Carpathian Mountains are a geographic barrier for wintering birds of prey.