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The study investigated the effect of microhabitat (emergent/submerged macrophytes) within lakes of different status (transparent/cloudy water) on the diversity and distribution of chironomid assemblages. Field and laboratory studies were undertaken bimonthly, from January to November 2008, in two shallow lakes of Polesie Lubelskie (eastern Poland), transparent water and cloudy water lake. The main objectives of the study were to compare the density and taxonomic richness of chironomids associated with emergent and submerged macrophytes within lakes of extremely different environmental conditions and to recognize the most important variables affected chironomid distribution between microhabitats within lakes. In transparent water lake, number of chironomid taxa varied between 12 (emergent macrophytes) and 18 taxa (submerged macrophytes) and was significantly higher than in cloudy water lake, 6 and 8 taxa, respectively. Mean abundance of chironomids associated with emergent macrophytes was higher in cloudy water lake. The opposite relation was observed on submerged macrophytes. The PCA analysis showed visible distinction of chironomid assemblages between microhabitats and lake types. The results of RDA led to determine the significant variables (Monte-Carlo permutation test) affected chironomid distribution. In both, transparent and cloudy water lake, the significant variables responsible for chironomids distinction between microhabitats were density and biomass of macrophytes, biomass of periphytic algae and pH. Moreover, nutrients, N-NO3 (transparent water lake) and P-PO4 (cloudy water lake), showed the significant influence.
Prunus serotina Ehrh. is a rapidly expanding invasive in European temperate forests, threatening native species biodiversity. Three alternative models, ‘the passenger’, ‘the driver’, and ‘the opportunist’ were used to determine the interactions between the invasive species, the native community, and features of the habitat. To assess the relationships between soil properties and species composition of a Scots pine forest invaded by P. serotina, we randomly selected twelve research plots in each of four stands in the south-western part of Poland. We used the phytosociological relevé method and determined selected soil properties (total nitrogen, organic carbon, and pH value) in the organic and humus horizons. Based on redundancy analysis, we determined that selected soil properties explained 38% of the total variation in species composition of the Scots pine forest with P. serotina, indicating that community interactions followed the ‘passenger’ model. At the same time, we found that P. serotina invaded via the ‘driver’ model, since the decrease in soil C:N ratio correlated with black cherry presence, and showed a significant impact on the floristic diversity in the invaded phytocenoses. We conclude that soil parameters seem to facilitate the invasion of P. serotina, and comprise the consequences of this process.
The small mammal species were investigated in the urbanized environment of Nitra city (Slovakia) in a multiscale-approach: at habitat level and at landscape level (urban-rural gradient). Continuous comprehensive rodent samplings from 2012 to 2015 were conducted in ten study sites, classified into three urban zones (landscape level). The total effort comprised 1,250 specimens of 13 species (Microtus arvalis, Apodemus sylvaticus, A. flavicollis, A. uralensis, Clethrionomys (Myodes) glareolus, M. subterraneus, Micromys minutes, Mus spicilegus, M. musculus, Crocidura suaveolens, C. leucodon, Sorex araneus, S. minutus) gathered in 14950 trapxnights. Environmental variables (habitat level) at each site were processed in the Geographical Information System as a proportion of landscape units around the trapping line and by a phytosociological survey. At the habitat level, we found a relationship between the landscape habitat structure and each species of small mammals. Diversity, species richness and relative abundance of small mammals decreased with the density of the built-up area. At landscape level, urban zones had a significant influence on species diversity, richness and relative abundance of small mammal populations. On the other hand, the presence of small mammal species precisely determined the urban zones, where we identified seven indicative species.
Data collected from 85 sample plots in Yazili Canyon Nature Park (deep, limestone valley; length - 6 km, area – 600 ha, height – 100–400 m) located in Mediterranean region (Turkey) yielded 24 endemic vascular plants. The endemic plant diversity and all vascular plant diversity indices were calculated for each sample plot using Simpson index. Regression analysis was performed between environmental factors, plant diversity and canopy closure. Endemic plant diversity showed a positive correlation with vascular plant diversity, and a negative correlation with slope position and altitude. A significant quadric relationship was observed between the endemic plant diversity and aspect variable. RDA (redundancy analysis) and CCA (canonical correspondence analysis) based on linear regressions were applied to determine the environmental factors affecting the distribution of endemic species, and the best model based on total variance explained was selected. According to RDA based on linear regression, habitat selection of endemics is strongly correlated with aspect, slope position and altitude. Lower altitude zone (300–500 m), the north aspect and lower slope including valley bottom of Yazili canyon were observed to be the most suitable areas for endemics.
Variation in vegetative and reproductive performance and leaf mineral composition among 25 populations of Colchicum autumnale (meadow saffron) from soils derived from six parent materials (limestone, marl, sandstone, greenstone, melaphyre and serpentine) in southwestern Poland has been investigated. The plant size (PS), total le-af area (TLA), leaf shape (LS), number of fruits per plant (NFP), number of seeds per plant (NFP), total weight seed per plant (TWSP) were estimated, and concentrations of seventeen elements (N, P, K, Ca, Mg, Na, S, Fe, Mn, Cu, Zn, Pb, Cd, Ni, Co, Cr, Mo) were analyzed in leaf and soil samples. In soil samples, also soil pH, organic matter content and sand, silt and clay content were determined. All soils (except melaphyre soil) contained elevated levels of Cr. Concentrations of soil Ni and Zn, Pb, Cd in serpentinite soil and polluted marl soils (respectively) were significantly higher than those of other examined soils. Meadow saffron leaves from all sites (except marl sites) contained elevated levels of Cr, Co and Ni. Statistical analysis, carried out with principal component analysis (PCA) revealed that a good correlation exists between the element content in leaves and plant performance traits and soil environment. The leaf Ca content and NFP were correlated and were much higher in populations from metal (except Cr) and nutrient-poor marl soils than in those from metal (except Ni in serpentine soil)and nutrient moderate rich soils derived from melaphyre, greenstones, serpentinite, limestones and sandstones and in those from metal-rich and nutrient-poor polluted marl soils. Meadow saffron plants tended to take up higher amounts of N, P, K, Mn, Cu and Na and lower amounts of S and had much higher TLA in populations from sandstone soils than those in populations from serpentinite, melaphyre, greenstone, marl and limestone soils. The leaf Co, Ni, Cr, Mg concentrations were correlated and were much higher in populations from serpentinite, melaphyre, greenstone, polluted marl and limestone soils than those from marl and sandstone soils. The pattern of variation in NFP and TLA across the different soil types was the opposite of that for leaf N, Cu, Na, Ni, Mg and S concentrations. Redundancy analysis (RDA) enables identification of the soil variables that best explain the variance pattern of plant response. The variation explained by the soil variables (15 soil elements and soil pH) was high (79%). The forward selection of soil variables identified soil Co, Mo, Ni, Ca and Zn concentrations as significantly influencing the ordination plant traits. The variation explained by these selected variables was 55%. Thus the five soil variables appeared to be the main factors determining the pattern variation of vegetative, reproductive and nutrient traits of Colchicum autumnale.
Leaf traits scaling relationships were compared in different months (May, June, July and August) in a temperate shrub species, Vitex negundo Linn. var. heterophylla (Franch.) Rehd. Leaf traits variation and the impact of environment were also studied. Our results showed that specific leaf area (SLA), leaf nitrogen content (Nmass), leaf phosphorus content (Pmass) and leaf chlorophyll content (Chlmass) were positively correlated, and all of the pairwise relationships showed a common standardized major axis (SMA) slope in different months. The variation of SLA, chlorophyll a content (Chlmass a), chlorophyll b content (Chlmass b), Chlmass a/b and maximum quantum yield of PSII (Fv/Fm) were mainly habitat-dependent, while the variation of Pmass and Nmass/Pmass were mainly month-dependent. Redundancy analysis (RDA) was used to further explore the relationships between leaf traits and environmental factors. We found that plants under shade (the relative photosynthetic photon flux density was about 10%) developed light-capturing behavior at leaf level (higher SLA) and cellular level (higher Chlmass/Nmass and lower Chlmass a/b). The increased Nmass/Pmass with month was mainly resulted from the large absorption of soil nitrogen and the decrease of soil pH. In a word, our study indicates that species may not have fundamentally different carbon capture strategies in different months. Variation of different leaf traits are related to different environmental factors in the field.
The relationships of Hildenbrandia rivularis (Rhodophyta), the species composition of its surroundings detailed environmental variables (water chemistry and hydrological, morphological and bottom features) in a lowland river (Wełna river, Western Poland) was investigated. H. rivularis from 40 stands was tested together with 25 environmental variables and vegetation. Detrended correspondence analysis (DCA) and redundancy analysis (RDA) were used to describe the relations between the species composition and the selected variables. The uniqueness of this protected species is an ability of formation incrustation on rocks but also coexistence with two groups of species: other algae and vascular plants. In study twenty-two plant taxa were recorded in 40 vegetation plots, including 4 macroscopic algae, 2 mosses and 16 vascular plants. The most common H. rivularis co-occurred with Leptodictyum riparium, Fontinalis antipyretica and Nuphar lutea. Most of the studied plots with red algae were characterised by shallow water and strong water velocity. H. rivularis prefers alkaline water with high conductivity. The results of the RDA, after forward selection, demonstrated that pH gradient, optical features such as dissolved organic matter and water colour – control the variation in the floristic communities with H. rivularis.
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