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The paper presents results of the studies conducted to determine causes and directions of transformations in vegetation of meadow-pasture communities in the area of the Wielki Łęg Obrzański [Great Obra Floodmeadows]. Multifaceted natural and habitat analyses were conducted on over 1800 relevés prepared in the vegetation seasons of 2005–2009 according to Braun-Blanquet. On their basis the phytosociological and floristic structure was analysed and habitat conditions were determined by phytoindication. Moreover, laboratory methods were applied in soil analyses to determine contents of basic macro- and microelements and groundwater table levels were recorded. Results referred to the documentation and archive literature made it possible to determine causes of transformations in plant communities in that area and outline probable directions in which succession was progressing. A lack of regular land use patterns is seen as the primary cause for the transformation in the flora of the Wielki Łęg Obrzański, particularly in the last 20 years. A considerable limitation of land use in certain sections of this area has led to the initiation of dominance of nitrophilic species such as Urtica dioica, Cirsium arvense, Potentilla anserina or Galium mollugo, while in the thinned sward it led to the development of grass species with very limited economic importance. Another equally important factor affecting the structure of vegetation cover is connected with air and water relations in soils, determined by the drainage system operating there for the last 200 years and by precipitation.
Using multiple classification approach to examine plant traits response to grazing and fencing (as without access to grazing) is rare. Here we used multiple classification approach to examine plant diversity, productivity and species traits response to grazing and fencing over a three-year period on the eastern part of the Qing-Hai Tibetan Plateau. The results showed that most common species response to the fence was poorly noticeable. The fencing meadows compared to those under long-term free grazing are characterized by significantly higher total species richness, but species richness declined with sampling years gradually, regardless of grazing or fencing. The correlation showed that species richness was negatively associated with mean annual temperature significantly, suggesting that abiotic factors (e.g. annual temperature) could also play important roles in driving species richness in this subalpine meadow. Total aboveground biomass was not associated with mean annual temperature and rainfall. The fencing meadow demonstrated higher community aboveground biomass relative to the grazing ones, especially the abundance of legume and graminoids increased, while the proportions of sedge decreased, suggested that grazing disturbance favours the increase of reproductive success of sedge (e.g. Kobresia humilis) in this subalpine meadow. Growth form-based analyses combined with canopy height categories should be recommended to reveal general rules and mechanisms relating to grazing.
Grasslands, especially those under ecological management (i.e. mowing, and grazing without fertilizers and chemicals), have significant importance for many arthropods, including ground beetles. We studied the abundance and species diversity of Carabidae of four uphill grasslands (West Sudety Mountains, Poland) under different management intensity: cattle grazing (one or four times per year), mowing, and alternatively managed (grazing/mowing). Beetles were collected using pitfall traps during three whole grazing seasons, i.e. from April to October in 2007–2009. The most frequent species of beetles, on each of the plots, were predators Poecilus cupreus, Calathus fuscipes and Nebria brevicollis. Sixtyfour ground beetle species were found altogether. Species richness ranged from 42 to 47, with the mean number of individuals per trap day-1 from 0.006 to 0.018. In the years of the study the number of ground beetles and their species diversity were higher on meadows mown once per year and alternatively managed grasslands as compared with grazed sites. Therefore, the simplified, organic way of agricultural production with reduced mowing or moving combined with grazing can be considered as appropriate in preserving the biodiversity of the grasslands in mountainous regions.
Vegetation structure and food availability can significantly modify the composition of farmland avifauna. In the 2006 breeding season we tested the effect of food resources (density of epigeic invertebrates) in two local habitats on foraging of farmland birds. We have been exploring how intensively the foraging birds utilise meadow and pasture habitats in an extensively used farmland area of Central Poland. Two plots were selected in adjacent meadow and pasture each of 0.18 ha where bird and invertebrate sampling was conducted in May 2006. We set five Barber traps active for two weeks at each plot to survey for the epigeic invertebrates which form the main part of farmland birds’ diet. In total, we trapped over two thousands invertebrate individuals (mainly Aranea, Coleoptera and Hymenoptera). Visual observations of foraging birds were performed from an elevated observation point located at a 25 m distance from the edge of the plots. We recorded 191 observations of foraging by 12 bird species (mainly Sturnus vulgaris L., Upupa epops L., Cuculus canorus L., Motacilla alba L., Corvus corone L., C. monedula L., Pica pica L.). We found that overall invertebrate density at the meadow was 2.5-fold higher than at the pasture. This was also the case with the invertebrate groups that were preyed upon by the birds. We recorded however a 10-fold higher frequency of foraging of birds at the pasture, as compared to the meadow. Preference of a bird species for foraging at the pasture was inversely correlated with its body mass. We discuss the importance of pastures for the preservation of farmland avifauna.
Quality of chosen herbal species from meadow and grazing herbage were evaluated. Dry matter, crude protein, ash, fat and fibre were analyzed. Herbage sampling was realized on three pastures of cattle with higher altitudes. Samples were compared with meadow herbage. Grass and herbage are the most natural and optimal feedstuff for cattle. Grazing management should notably regulate the pasture composition, i.e. support dominance of soft stoloniserous strains of grasses and decrease occurrence of weed and less value strain of gramineous grasses. The impact of grazing on milk performance and health of dairy cows was surveyed on sub-moun- tain farms. The higher milk, fat and protein yields were found in grazing season in comparison with winter confinement period.
Agricultural use of land on hydrogenic soils is associated with lowering the groundwater level, which intensifies the processes of organic matter mineralisation and, in effect, releases large amounts of mineral nitrogen. The aim of the study was to determine the seasonal variability of the concentrations of nitrogen mineral compounds (N-NO2, N-NO3 and N-NH4) in groundwater under extensively managed peat-muck soils, situated in Wrocikowo in the Olsztyn Lakeland and in the Dymerskie Meadows in the Mrągowo Lakeland. Peat-muck soil, found at the study sites, had varied physical properties. The highest content of mineral particles (69.3%) in the muck layer was found in soil marked as MtI 120gy under turf-covered wasteland, and in the peat layer (51.5%) – in soil marked as MtII 60gy under extensively managed meadow. Groundwater taken from piezometers installed in hydrogenic soils was used as the study material. Water for chemical determinations was taken during four seasons: spring – in May, summer – in August, autumn – in November and winter – in January. The concentration of mineral forms of nitrogen in groundwater of peat-muck soil was found to depend on its type, the depth where the groundwater was found and the type of soil use. The highest concentration of mineral nitrogen was found in summer (1.62 mg dm–3 on average), and the lowest (1.11 mg dm–3 on average) was found in winter. The concentration of mineral nitrogen in groundwater of extensively managed peat-muck soil ranged from 0.81 to 2.27 mg dm–3 and was found to be dependent on the type of soil rather than its use. Lowering the level of groundwater in peat-muck soil increases the concentration of mineral forms of nitrogen, especially N-NH4. Ammonium nitrogen was the dominant form of nitrogen in the groundwater of peat-muck soil (MtII 60gy and MtI 120gy) of non-managed and extensively managed meadows, whereas nitrate nitrogen was the dominant form of the element in the MtIc 35gy soil under the meadow and the MtII bb under the pasture.
Semi-natural grasslands managed by mowing and grazing are an important part of European landscape. Orthopterans are considered to be an appropriate indicator to assess the impact of agricultural management on grassland ecosystems. We studied effects of mowing, grazing and two kinds of edges on Orthoptera of submontane hay meadows and pastures in the Hrubý Jeseník Mts. (Czech Republic). Using sweep netting and pan trapping, we sampled orthopteran assemblages associated with the farmland managed for at least five years under Czech agri-environmental schemes. In total we collected 2253 individuals of orthopterans representing 14 species. The short-term impacts of mowing and grazing were tested by multivariate ordination analyses. The results indicate that mowing significantly decreased Orthoptera species abundance. Conversely, the response of orthopterans to grazing was not statistically significant and appeared to be species-specific. The abundance of acridid Gomphocerippus rufus increased substantially with grazing, which is in contrast with its negative response to mowing. The negative influence of mowing on grassland inhabitants can be mitigated by lower mowing frequency and by providing temporary uncut refuges. The results of generalized linear models showed significant increase of both species richness and total abundance of Orthoptera towards the baulks. Therefore, the refuges should be established primarily along grass baulks or similar types of permanent grassy edges. As a general rule an effort should be made when managing grasslands to ensure the highest habitat heterogeneity.
Prevalence, intensity and abundance of protostrongylid larvae in snails and slugs were studied on 10 sheep and goat pastures in the region of Stara Zagora, Southern Bulgaria, in 2001. Eight gastropod species were infected: Helicella obvia, Cernuella virgata, Monacha cartusiana, Zebrina detrita, Cepaea vindobonensis, Chondrula microtraga, Helix pomatia and Deroceras reticulatum. Four nematode species were identified: Muellerius capillaris, Neostrongylus linearis, Cystocaulus ocreatus and Protostrongylus sp. Helicella obvia was the most common and abundant snail, and showed the highest infection parameters. Cernuella virgata was the only species in one pasture and had high infection descriptors. Monacha cartusiana and Zebrina detrita had high infection levels in some pastures. A subset of data representing the infection of H. obvia was used to test for relationships with environmental characteristics. Protostrongylid infections in this host species showed considerable variation between sites. M. capillaris had the highest prevalence and intensity, followed by C. ocreatus and Protostrongylus sp. Comparisons of sites at lower vs at upper elevations did not show significant differences in infection, with the exception of Protostrongylus sp. The primary vegetation was the only explanatory variable for the total prevalence of protostrongylids. This variable, in a combination with altitude, mollusc species richness and sample size explained 73% of the variation of mean intensity. In the models explaining variations in the prevalence and the mean intensity of the nematode species, 9 variables were included: primary vegetation, altitude, annual precipitation, mean annual precipitation, mollusc and nematode species richness, concentration of inorganic nitrogen in soil, snail population density and ratio between the number of goats and the number of sheep grazing on pasture. H. obvia was considered a suitable screening species for assessing the pasture contamination in the region.
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