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1

Grassland ecosystems in the varied hydrological and ecological conditions of the Kulawa River Valley

100%
Prajs B., Antkowiak W.
Polish Journal of Environmental Studies
|
2010
|
tom 19
|
nr 1
131-139
Grasslands in the Kulawa river valley (ca. 10 ha) were subject to land improvement in the 19th century, and remnants of the hydrotechnical system and overgrown ditches are still present. This study aims to: (1) evaluate the present meadow ecosystems; (2) predict their changes under the influence of the planned restoration of the hydrotechnical system and (3) compare results of various methods: phytoindication, phytosociological, floristic, and principal component analysis. The applied methods complemented one another. The devastation of the hydrotechnical system and the lack of utilization of the grasslands have led to either drying or waterlogging of the soil, and to changes in vegetation. The plant communities that have developed there represent the intermediate stage of regressive succession, and belong to the orders Arrhenatheretalia, Molinietalia, and the class Phragmitetea. Particularly the patches growing on relatively dry, strongly decomposed peaty soil have lost the characteristics of damp meadows. Meadow species have declined there, and nitrophilous species have replaced them. Only a local depression without outflow, which was earlier drained, is now waterlogged again, with a mosaic of calcareous fen, meadow, and marsh vegetation, including large populations of 11 species that are rare, protected, or listed as indicator species for the Natura 2000 habitat 7210*. Results of this study indicate that the present conditions in the waterlogged depression should be preserved. In contrast, the dry patches should be irrigated and subject to extensive farming.
2

Ground-active arthropod recovery in response to size of shrub plantations in a desertified grassland ecosystem

100%
Liu R., Liu J., Zhao J., Xi W., Yang Z.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 3
The ground-active arthropod diversity response to size of shrub plantations in desertified grassland ecosystems is largely unknown. In the study ground-active arthropods were collected by pitfall trapping beneath shrub canopy of very low, low, medium and high size, with adjacent mobile sandy land as a control. It was found that arthropod dominant taxa from mobile sandy land were significantly distinctive from those from plantations of different shrub size. A considerably lower Sørensen index (i.e., 0.25–0.48) was found between the arthropod communities from mobile sandy land and the canopy of either shrub size, than between those under low and medium/high shrub size (i.e., 0.62 to 0.69). The arthropod total abundance was significantly greater under the shrub canopy of very low size in comparison to that of low and medium shrub size and mobile sandy land, with the intermediate values under shrub canopy of high shrub size. Taxon richness and diversity of arthropod communities were distinctly lower under the shrub canopy of low size in comparison to very low, medium and high shrub size. The shrub size was found to have different effects on the density and richness distribution of arthropod trophic groups (i.e., predators, phytophagous, saprophagous, and omnivorous). It was concluded that shrub plantations could facilitate ground-active arthropod diversity recovery when they were afforested in mobile sandy land. There was a contrasting effect of shrub size on ground-active arthropod diversity recovery versus arthropod abundance when grazing was excluded.
3

Chemical properties of litter of forest and grassland ecosystems: transect studies in Siberia [Russia]

100%
Bienkowski P., Titlyanova A. A., Shibareva S. V.
Polish Journal of Ecology
|
2006
|
tom 54
|
nr 1
The aim of this paper was to study comparatively the amount, chemical composition and energy content of litter from forest and grassland ecosystems along a transect in Central Siberia, running from the north (68°N, Forest tundra) to the south (50°N, Dry steppes); it is about 2 000 km. In the boreal forests litter standing crop ranges from 15 to 78 t·ha⁻¹ d.w., in subboreal birch stands – it is about 17 t·ha⁻¹ d.w. and in grasslands – the litter standing crop decreases southward along the transect from 6 to 1.5 t·ha⁻¹ d.w. All kinds of litter are rich in reduced compounds and have negative oxidation degree. Nevertheless oxidation degree increased from North to South in both ecosystem groups: from –0.6 to –0.3 in the boreal forests and from –0.5 to –0.2 in the subboreal ecosystems. The chemical composition of litter is specific and differs from both initial substrates, i.e. phytomass and products of humification. The litter contains as many carbon as fulvic acids, as many oxygen as humic acids and much more hydrogen than both acids together. Energy content values of litter were estimated to be lower than that of humic acids and higher than energy contents of fulvic acids. The transformation of litter organic substances seems to be shifted to the formation of fulvic acids. The content of minerals in litter changed in both series (forest and grassland) in the following order Si> Ca> F> Al> S> Mg> K> P> Na.
4

Spatial heterogeneity of soil seed banks in sandy grasslands under fencing and grazing in Horqin sandland, Northern China

84%
Zuo X., Zhao X., Zhao H., Zhang T., Wang S., Knops J., Kochsiek A.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 2
Understanding composition, structure and spatial heterogeneity in soil seed banks is important for the management of grassland ecosystem. Although the effect of fencing and grazing on vegetation composition is widely known, information on species composition, seed density and spatial heterogeneity of soil seed banks in sandy grasslands under fencing and grazing is still lacking. We measured the species composition and seed density of soil seed banks in fenced grassland, grazed grassland and grazed shrubby grassland in Horqin Sand Land, Northern China. By applying the geostatistical methods, we assessed how fencing and grazing affected spatial heterogeneity of soil seed banks in sandy grasslands. Total seed density and species richness in soil seed banks were lower in fenced grassland than in either grazed grassland or grazed shrubby grassland. Seed density and species richness of annual species in soil seed banks were also lower in fenced grassland than in either grazed grassland or grazed shrubby grassland, while those of perennial species showed a reverse trend. The analysis of spatial autocorrelation ranges, fractal dimensions and distribution pattern maps from geostatistical methods showed that spatial heterogeneity of seed density and species richness in soil seed banks were also lower in fenced grassland than in either grazed grassland or grazed shrubby grassland. Continuous fencing increases the seed density and species richness of perennial species in soil seed banks, as well as results in a decrease in spatial heterogeneity of seed density and species richness in soil seed banks. So, continuous fencing should be considered to restore the degraded sandy grasslands in management of semiarid grassland ecosystems.
5

Effects of litter accumulation on plant communities in fenced desert steppe

84%
Li X., Liu B., Chen L., Song N.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 3
The litter decomposition plays an important role in nutrient circle of grassland ecosystem, the water holding ability of litter and physical and chemical characteristics have been studied exclusively over the past century. However, the effect of litter accumulation on plant community in desert steppe under fenced condition was little known. In this study, four typical plant communities were employed to identify the effects of litter accumulation on plant communities. The results showed the trend of litter accumulation amount in the four different types of plant communities was best represented by Birk model. The accumulation of litter had different effects on the number of seedlings. When litter accumulation reached 300–400 g cm⁻², green-up dates advance 7 days. The amount of seedling germination and the number of plant species reached a peak. Meanwhile, plant density, coverage, average height, richness, and evenness reached maximum values. It was concluded that when opposite fencing time was about 6 years, and the optimum amount of litter accumulation was about 300–400 g cm⁻², which could advance the green-up dates and increase the number of plant seedlings, and also improve or maintain community stability. Such a notion has to be taken into account for the development of an improved policy for environmental management in desert steppe.
6

Fractal features of soil particle size distributions and their implications for indicating enclosure management in a semiarid grassland ecosystem

84%
Chen W., Chang H., Liu R.
Polish Journal of Ecology
|
2020
|
tom 68
|
nr 2
7

Role of seed bank in establishment of single and mixed-sowing artificial grasslands of Tibetan Plateau

84%
Ma Z., Zhang C., Zhou H.-K., Yao B.-Q., Zhao X.-Q.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 4
Artificial grassland establishment is one of the fastest and most effective ways to restore the productivity of degraded grasslands. Little is known about the effect of different types of artificial grassland establishment (i.e., single- and mixed-sowing grassland establishment with perennial grasses) on soil seed bank in degraded grassland ecosystems. Single-sowing population of a high yield species usually has a great standing biomass causing shading that may inhibit germination of seeds in soil seed bank. Thus, we hypothesized that there is higher species richness and seed density in the soil seed bank of single-sowing than mixed-sowing grasslands. Here, we investigated the soil seed bank in four-year old single-sowing and mixed-sowing and control (degraded) grasslands on the Qinghai-Tibetan Plateau. We found that the autumn seed bank of mixed-sowing grasslands had lower species richness and seed density than single-sowing grasslands, while the summer soil seed bank (persistent seed bank) showed little differences. There were differences in biomass among the three grasslands (single-sowing > mixed-sowing > control), but there was no differences in species richness of vegetation. In sum, our results of the autumn seed bank support our hypothesis. Greater above-ground biomass in single-sowing grasslands could generally cause low light availability preventing seeds in soil from germinating and support more seed output, which both may indirectly or directly result in the relatively higher species richness and seed density in the soil seed bank. Our results also suggest that artificial grasslands usually returning to native grasslands in terms of production and species composition after several years is likely due to stability of the persistent soil seed bank.
8

Impacts of moving, grazing and edge effect on Orthoptera of submontane grasslands: perspectives for biodiversity protection

84%
Rada S., Mazalova M., Sipos J., Kuras T.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 1
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.
9

Species diversity of submontane grasslands: effects of topographic and soil factors

67%
Kopec M., Zarzycki J., Gondek K.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 2
The grassland ecosystems generally, and the submontane meadow vegetationparticularly, are important components of the natural diversity of landscape. In the montane range (600–1000 m a.s.l.) (Beskidy Mts. Southern Poland) the richness (number of species) and the diversity (assessed with several indices) of meadow vegetation (permanent grassland and formerly arable land) were studies on 356 plots of 100 m² each using the method of Braun-Blanquet. The correlation with several topographic factors (altitude, inclination, exposure), as well as with soil chemical factors (pH, nutrient like P and other macroelements content) was elaborated and the Ellenberg’s indicator values in respect to moisture, acidity and fertility were calculated. It was found that the main factor diminishing species diversity was the increasing of altitude from 343 m to 963 m and soil acidification from 3.4 to 6.5. No significant difference was noted between the diversity indexes (Shannon-Wiener and Simpson) of three study communities. The soil fertility affected the number of species in the plant communities in the opposite way. In the case of communities of Molinio-Arhenatheretea class occurring on more fertile habitats, fertility increase caused a decline in the number of species, whereas in the communities from Nardo-Callunetea class developed on extremely poor habitats – the number of species was growing with increasing fertility
10
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Conservation of vegetation cover in the Gluszec stream valley in Poznan (Poland) in the agri-environmental program

67%
Borysiak J., Grabowska B., Kubala T.
Roczniki Akademii Rolniczej w Poznaniu. Botanika-Steciana
|
2013
|
tom 17
The vegetation cover of the Głuszec stream valley was investigated. The article presents a list of 294 recorded species of vascular plants from 65 families and, also, 47 plant associations from nine classes, from three dynamic vegetation circles: Carici elongatae-Alnetum, Fraxino-Alnetum and Querco- -Ulmetum minoris. Six types of vegetation complexes were documented. Their phytocoenotic structure was shown in a table containing 􀍻􀎂 relevés made in sigmassociations. The preliminary results of research on the dynamics of Dactylorhiza incarnata population, occurring in one of meadow complexes, were presented. The Głuszec stream valley was recognised as the region of exceptional natural plant cover within the city of Poznań and proposed to be incorporated into the green network of the Poznań Agglomeration. The valley was also included in the agri-environmental program. An active protection of grassland ecosystems is achieved by adhering to the requirements of this program and additional recommendations of an expert botanist.
11

Foraging ecology and spatial behaviour of the red fox (Vulpes vulpes) in a wet grassland ecosystem

67%
Meisner K., Sunde P., Clausen K. K., Clausen P., Faelled C. C., Hoelgaard M.
Acta Theriologica
|
2014
|
tom 59
|
nr 3
We investigated diet composition, habitat selection and spatial behaviour of the red fox (Vulpes vulpes) in relation to the availability of wader nests in a coastal polder area in southwest Denmark. The predatory role of the red fox in wet grassland ecosystems has profound implications for conservation status of declining populations of grassland breeding waders. However, few studies have focussed on the foraging ecology and behaviour of the red fox in these landscapes. Faecal analyses revealed that fox diet consisted of birds (43 % of prey remains / 32 % of biomass), rodents (39 % / 21 %), sheep (mainly as carrion, 14 % / 41 %) and lagomorphs (4 % / 7 %). Charadriiformes (including waders) comprised 3–12 % of prey remains throughout the year. Telemetry data and spotlight counts indicated that foxes did not select areas with high densities of breeding waders, suggesting that foxes did not target wader nests while foraging. Foxes maintained stable home ranges throughout their lives, indicating that the area sustained a permanent fox population all year round. The population densities, estimated from spotlight surveys, were 0.74 visible foxes km−2 (95 % CI; 0.34–1.61) on the preferred breeding habitat for waders and 1.21 km−2 in other open habitats such as cultivated fields. Our results indicate that red fox predation on wader nests is incidental, consistent with the notion that red foxes are generalist predators that opportunistically subsist on many prey groups.
12

Geomagnetic conditionings of floristic diversity of grassland ecosystems

67%
Janowski T. M., Kostuch R., Podgorni Z.
Acta Agraria et Silvestria. Series Agraria
|
1995
|
tom 33
81-88
In the years 1993 and 1994 were carried out geomagnetic researches on the selected plant communities of grassland near Krakow. The authors have received first of all the quantities data (nT) and graphic characteristics in selected places. Then were made phitosociological researches of the sward and graphic registration of plant cover by dominant plant species. It was found that on the experimental fields there were four types of plant associations. On the geomagnetic- fields in homogenous (with (he big anomalies) in the limits to 10000 nT there were always some dominant plants. Whereas on the homogenous fields, where the geomagnetic tensions was too higher (dozens thousants) nT there was only one dominant plant.
13

Night-time CO2 chamber measurements in peatland ecosystem in Poland

67%
Juszczak R., Acosta M., Michalak M., Chojnicki B. H., Urbaniak M., Drosler M., Augustin J., Olejnik J.
Acta Agrophysica. Rozprawy i Monografie
|
2010
|
nr 2[179]
14

Effect of 5 years long cessation of grazing on methane uptake in a semi-arid grassland

67%
Zhou X., Hao Y.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 4
Grazing exerts a key role in nutrient cycling in grassland ecosystems, however, little is known about the effe cts of short-term enclosure on methane (CH₄) fluxes in a semi-arid steppe biome like this of Inner Mongolia. CH₄ fluxes were measured in the Leymus chinensis (Trin) Tzvel. grassland using static chamber and gas chromatography (GC). Measurements were carried out twice per month over a growing season in 2004 at the two sites (one fenced since 1999 (UG99) and the other subjected to freely grazing (FG)). All CH₄ fluxes were positive, indicating that this grassland functioned as the active atmospheric CH₄ uptakes. During this period, the UG99 site (57.6 ± 6.7 μg C m⁻² h⁻¹) had significantly higher mean CH₄ uptake in comparison to the FG site (37.0 ± 6.3 μg C m⁻² h⁻¹). A significant liner negative correlations between CH₄ uptake and soil moisture (0–5 cm) at the both sites were found (P <0.05). The results indicated that short-term enclosure was helpful to improve CH₄ uptake in this area.
15

Variability and long-term changes in the species composition of Molinia meadows in Poland: a case study using a large data set from the Polish Vegetation Database

51%
Kacki Z.
Acta Botanica Silesiaca. Monographiae
|
2012
|
tom 07
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