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Contributions to the flora of steppes of the Black Sea Region [Ukraine]

100%
Moisienko I., Gorski P., Boiko P.
Roczniki Akademii Rolniczej w Poznaniu. Botanika
|
2002
|
tom 05
2

Collembolan communities in steppes of Ubsu-Nur biosphere reserve [Tuva]

100%
Stebaeva S. K.
Polskie Pismo Entomologiczne
|
1995
|
tom 64
|
nr 1-4
3

Dianthus campestris [Caryophyllaceae], a species new to Poland

84%
Pawlikowski P.
Polish Botanical Journal
|
2008
|
tom 53
|
nr 1
91-94
4

Impact of the invasive species Elaeagnus angustifolia L. on vegetation in Pontic desert steppe zone [Southern Ukraine]

84%
Sudnik-Wojcikowska B., Moysiyenko I., Slim P. A., Moraczewski I. R.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 2
269-281
The Irano-Turanian species – Russian olive (Elaeagnus angustifolia L.) – is one of most commonly planted tree in the shelterbelts in southern Ukraine. The consequences of introduction of the species from windbreaks, into areas of different land use in west and central Pontic desert steppe zone are evaluated. The above steppe is unique on a European scale and exists only in some parts of the Black and Azovian Sea coasts. In recent years, the socio-economical crisis in Ukraine (less intensively cultivation, as well as limited grazing) has been responsible for the intensification of the spread of alien tree species outside the windbreaks. Studies were conducted in Kherson Region, in the immediate vicinity of the Black Sea Biosphere Reserve, where the presence of aliens is undesirable. The analysis of phytosociological material (48 relevés with and without Russian olive) collected from areas of different land use type and limited human pressure (as abandoned field, former intensively grazed solonetz and extensively grazed desert steppe vegetation) show that E. angustifolia can impede the regeneration of the desert steppe. The species creates favourable conditions for the growth of geographically and ecologically alien nithrophilous weeds.
5

Zonal character of the flora of kurgans in central and southern Ukraine

84%
Sudnik-Wojcikowska B., Moysiyenko I. I.
Biodiversity: Research and Conservation
|
2010
|
tom 17
6

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.
7

Ramet recruitment from different bud types along a grassland degradation gradient in Inner Mongolia, China

84%
Qian J., Busso C. A., Wang Z., Liu Z.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 1
Since the contribution of total belowground bud bank and different bud types to community regeneration has rarely been explored, the vegetative offspring recruited from different belowground bud types was investigated in four plant communities along a grassland degradation gradient in northeastern China (Inner Mongolia). This gradient, between 1000 and 1500 m a.s.l., has been caused by overgrazing. It is a Leymus chinensis steppe which occupies about 3.0×10⁵ ha. Recruitment from tiller buds was dominant (>80%) in determining the total vegetative offspring density along the whole grassland degradation gradient. However, the proportional contribution of tiller-ramets to total ramet recruitment was significantly greater (P <0.05) during earlier than later stages of grassland degradation, while that of rhizome-ramets showed an opposite pattern. While the percentage contribution and density of root-derived ramets to total ramet density increased significantly (P <0.05) during the late stages of grassland degradation, those of bulb-ramets kept relatively constant along the whole grassland degradation gradient. The relative contribution of hemicryptophytes [i.e., Achnatherum sibiricum, Cleistogenes squarrosa, Festuca ovina, Koeoleria cristata, Poa annua, Stipa grandis] to total plant species richness decreased, while that of geophytes [i.e., Agropyron cristatum, Carex korshinskyi. Leymus chinensis, Allium anisopodium, A. bidentatum, A. tenuissimum, Astragalus galactites, Cymbaria dahurica, Iris tenuifolin, Potentilla acaulis, P. bifurca, Pulsatilla turczaninovii, Serratula chinensis, Thalictrum aquilegifolium] increased with the increases of grassland degradation. Our results showed that as grassland degradation increased, changes in the proportion of tiller-, rhizome- and root-derived ramets with respect to total ramet density determined in turn changes in the proportion of hemicryptophytes and geophytes in the study plant communities.
8

Water- and N-induced changes in soil C:N:P stoichiometry and its implications for N limitation of a desert steppe species, Glycyrrhiza uralensis

84%
Huang J., Yu H., Zhang F., Li M., Lin H.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 2
Changes in precipitation patterns and the deposition of atmospheric nitrogen (N) increase the possibility of altering soil carbon (C):N:phosphorus (P) stoichiometry through their effects on soil C and nutrient dynamics, especially in water- and N-limited ecosystems. We conducted separate 2-year watering and N addition experiments, and examined soil C:N:P stoichiometry, relative growth rate, and leaf N resorption traits of Glycyrrhiza uralensis Fisch in a desert steppe of northwestern China. Our objectives were to determine how soil C:N:P stoichiometry responded to climate change, and its indications for plant growth and N resorption. The results showed that additional water increased N loss and thus decreased N availability, resulting in high N resorption from senescing leaves of G. uralensis. N addition increased N availability, consequently reducing plant N dependence on leaf resorption. High relative growth rates occurred with intermediate N:P and C:N ratios, while high N resorption occurred with a low N:P ratio but a high C:N ratio. Our results indicate that soil C:N:P stoichiometry also could be a good indicator of N limitation for desert steppe species. Altered soil C:N:P stoichiometry affects the N strategy of plants, and will be expected to further influence the structure and function of the desert steppe community in the near future.
9

Spatial organization of a bank vole population in a forest-steppe oak forest

84%
Chistova T.
Polish Ecological Studies
|
1994
|
tom 20
|
nr 3-4
10

Intensity of organic matter decomposition in various landscapes of Caucasus [Daghestan]

84%
Fischer Z., Niewinna M., Yasulbutaeva I.
Polish Journal of Ecology
|
2006
|
tom 54
|
nr 1
Decomposition process in the soil of desert, steppe and mountain landscapes was studied in the region of Caucasus (Daghestan). The study sites differed mainly in average temperature and humidity being generally extremely dry with soil poor in organic matter. Two methods – bags with grass and cellulose filter paper discs were used. No dependence was found between the rate of decomposition of introduced organic matter and organic nitrogen content, and C:N ratio in soil, but strong dependence was found with temperature and humidity conditions. The measured rate of organic matter decomposition in soil of desert, steppe, and mountain sites indicated that the level of decomposition activity of these soils is high. In summer it is lowest in steppe (1.97 mg · g⁻¹ · 24 h⁻¹), whereas the highest in mountains (5.68 mg · g⁻¹ · 24 h⁻¹). The annual average rate of decomposition of cellulose discs and hay in mountain site was almost two times higher than in steppe site and nearly three times higher than in desert site. Mainly climatic conditions i.e. long-lasting drought (almost all the year) in desert as well as in steppe (January to August) are responsible for this difference.
11

Holocene micromammal complexes of Belarus: A model of faunal development during Interglacial epochs

84%
Motuzko A. N., Ivanov D. L.
Acta Zoologica Cracoviensia
|
1996
|
tom 39
|
nr 1
12

Dynamics of sandy desertification and detection of sandy land-steppe boundary: vegetation and soil properties

67%
Xu D., Xu X., Xie Y., Wang K.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 2
Desertification is one of the most serious environmental problems on a global scale. China suffers from desertification over large areas. Landscape boundaries profoundly influence the structure and function of landscapes, and influence ecological processes both locally and over large scales. Data on soil properties and vegetation collected on three 110 km parallel transects across sandy land-steppe transition zone in Yanchi county, Ningxia region, northwestern China, were used to analyze changes along the sandy land/steppe boundary by using the Moving Split Window (MSW), to determine desertification dynamics, and to explore changes of vegetation and soil properties among different desertification degree. Combining the dissimilarity profiles of soil particle size with importance value (IV) of vegetation, four boundaries were detected along transects. According to the four boundaries, we divided the whole sandy land/steppe ecotone area into five desertification categories: potential desertification (PD), light desertification (LD), medium desertification (MD), severe desertification (SD) and extreme desertification (ED). Sand fractions increased, while silt and clay fractions, soil organic C, total N and available N decreased and exhibited clear gradient changes from the potential desertification land to the extreme desertification land. All areas we studied have been desertificated at different degree based upon soil particle compositions at different depths. With the aggravation of sandy desertification, the steppe species dominating in the potential desertification land gradually gave place to arid and sand tolerant perennials and therophytes and eventually to psammophyte annuals and shrubs in the extreme desertification land.
13

Diet selection of the southern vizcacha (Lagidium viscacia): a rock specialist in north western Patagonian steppe, Argentina

67%
Galende G. I., Raffaele E.
Acta Theriologica
|
2012
|
tom 57
|
nr 4
The southern vizcacha (Lagidium viscacia) is a rock specialist that inhabits small colonies in isolated rocky outcrops of northwestern Patagonia. This study analyzes its diet selection in relation to food availability, establishes the degree of dietary specialization, and discusses the potential competition with exotic herbivores. Diet composition and food availability were determined in summer and winter in eight rocky outcrops by microhistological analysis of fecal pellets, and food availability was estimated by the Braun Blanquet cover abundance scale. Vegetation cover differences were detected by using a random analysis of variance (ANOVA) factorial block design, and dietary preferences were determined by the confidence interval of Bonferroni. The southern vizcacha showed a specialized feeding behavior despite the consumption of a wide variety of items. Their diet was concentrated on a few types of food, mainly grasses, and the trophic niche was narrow and without seasonal variations. In winter, when food was scarce and of lower quality than summer, diet was dominated by Stipa speciosa, suggesting a selection according to the selective quality hypothesis. Our results (narrow trophic niche, restricted activity near rocky outcrops, and a diet with high proportions of low-quality grasses) showed that the vizcacha is an obligatory dietary specialist, and these characteristics made it highly vulnerable to changes in food availability. In this scenario, overgrazing caused by alien species with similar diets, as the European hare and livestock, could negatively affect their colonies.
14

Population dynamics of five sigmodontine rodents of Northwestern Patagonia

67%
Guthmann N., Lozada M., Monjeau J. A., Heinemann K. M.
Acta Theriologica
|
1997
|
tom 42
|
nr 2
Population dynamics of five rodent species were studied, from March 1991 to August 1994, in an area located in the ecotonal steppe of northwestern Patagonia, Argentina {at about 40°S). Seasonal and annual fluctuations in population numbers were found in all sigmodontine species. The reproductive period, sex ratio and longevity of the five species were also studied. Abrothrix xanthorhinus (Waterhouse, 1837), a habitat generalist, was the most abundant species. Eligmodontia morgani (Allen, 1901), Abrothrix longipilis (Waterhouse, 1837), Reithrodon auritus (Fischer, 1814) and Oligoryzomys longicaudatus (Bennett, 1832) were subdominant. The present study is a first description of the population dynamics in this rodent community, whose ecological characteristics gather importance considering that some of these species are Hantavirus reservoirs.
15

Taxonomic investigations of cyanobacterial and algal flora from the Southern Altai, East Kazakhstan

51%
Caisova L., Besta T., Chlachula J., Komarek J., Husak S.
Biodiversity: Research and Conservation
|
2009
|
tom 15
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