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1

Geographic and seasonal variability in feeding behaviour of a small herbivorous rodent

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Sassi P. L., Borghi C. E., Dacar M. A., Bozinovic F.
Acta Theriologica
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2011
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tom 56
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nr 1
Foraging strategies have traditionally been modelled as a result of food selection in response to one factor, as for instance resource availability, deterrent compounds or nutrients. Thus, a trade-off is assumed between plasticity (generalist strategy) and efficiency (specialist strategy). Nevertheless, several studies have demonstrated that animals cope behaviourally with food supply variation. For instance, desert-dwelling rodents partially compensate for nutritional bottlenecks through diet selection. The aim of our study was to test how foraging behaviour matches spatial and temporal variations in the trophic environment and how modelling hypotheses help us to understand the resultant foraging strategy. Our animal study model was the small cavy Microcavia australis, a widely distributed herbivorous rodent. Fieldwork was carried out in four places, in wet and dry seasons. We found significant differences in plant cover, plant diversity and niche breadth, and diet selection revealed a complex foraging strategy. M. australis shows a behavioural repertoire that exceeds single-criterion categories; therefore, we appeal to theoretical models that consider ecological and physiological perspectives. We classified the small cavy as a facultative specialist displaying a thoroughly opportunistic strategy based on the plasticity of the behavioural phenotype. We finally discuss the evolutionary relevance of our results and propose further investigation avenues.
2

Konik polski horses as a mean of biodiversity maintenance in post-agricultural and forest areas: an overview of Polish experiences

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Doboszewski P., Doktor D., Jaworski Z., Kalski R., Kulakowska G., Lojek J., Plachocki D., Rys A., Tylkowska A., Zbyryt A., Gorecka-Bruzda A.
Animal Science Papers and Reports
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2017
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tom 35
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nr 4
Traditional agricultural measures are still necessary for maintenance of endangered endogenous species of plants and animals in ecologically valuable habitats. Poland is one of the countries of the highest biodiversity of agricultural lands in Europe, however, the intensification of agriculture and farming resulted with regular decrease of valuable wildlife species. Abandonment of agricultural use of traditionally pastoral areas induced the encroachment of species that reduce local biodiversity. To counteract this undesirable process, several organisations re-introduce Konik polski horses into wastelands. The aim of this overview is to share the experiences of institutions which used Konik polski horses as a mean for biodiversity restoration in post-agricultural and forest areas, including expected effects, their implementation and main problems encountered. The aims, positive and negative effects are presented and discussed.
3

The effects of elevation on the morpho-anatomical and ecological traits in Cyclamen coum subsp. coum Mill. populations in the Central Black Sea Region of Turkey in contrasting habitats

100%
Ozbucak T. B., Polat G., Akcin O. E., Kutbay H. G.
Polish Journal of Ecology
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2017
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tom 65
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nr 2
The differences in morpho-anatomical, ecological and biochemical traits of Cyclamen coum subsp. coum, threatened plant listed in CITES (Convention on International Trade in Endangered Species of Wild Fauna & Flora) have been investigated in the central Black Sea region of Turkey in the context of its distribution at different altitudes. We found that shoot length, bulb width, leaf width and length, number of branches and flowers were significantly different along elevation gradient, whereas length of tubers, number of living and dead leaves, number of nodes, specific leaf area (SLA) and leaf mass area (LMA) values, did not differ significantly, PCA analysis revealed that leaf length and width, the number of branches, soil organic matter content and available potassium concentration and N concentrations of above and belowground parts and reproductive effort (RE3) played significant role in differentiation of the studied populations, while several other studied factor were found not significant. The reproductive effort of individuals from the sea level was higher. We suggest that significant differences in the studied traits may indicate the ecotypic differentiation among populations.
4

Impacts of environmental heterogeneity on distribution pattern of moss crust patches in temperate desert in Central Asia

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Ji X.-H., Pang S.-Q., Zheng Q.
Polish Journal of Ecology
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2018
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tom 66
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nr 2
Moss crusts are the highest developmental stage of biological crusts in arid and semiarid ecosystems worldwide. Under natural conditions, elementary functional units of moss crusts are patches. However, to date, the quantitative features, distribution pattern, ecological effect and relationship with environmental factors of moss patches in desert ecosystems remain unclear. In this study, 3303 moss patches in 22 plots and relevant environmental variables were investigated and quantified in the Gurbantunggut Desert, China. Thirty-six patch classes were defined. Moss crusts accounted on average for 11.7% of the plot area, and the mean moss patch area was 23.4 cm². Small patches dominated, indicating a serious fragmentation of moss crusts. Significant density-dependent effects between patch density and size, humped relationships between patch size and moss plant density, and soil water content under moss patches were observed. The overall distribution of moss crusts showed a tendency of moss patch size and moss plant density decreasing from the southeastern part of the desert to the northwestern part, while moss patch density showed the opposite trend. Pearson's correlation analysis and nonmetric multidimensional scaling analysis consistently demonstrated that the distributions of moss patches were dominantly influenced by non-moss crust coverage, sand particle size, latitude, mean annual precipitation (MAP) and mean annual temperature. Of these parameters, fine sand, high MAP and low latitude were beneficial to the development of moss crusts. Consequently, the factors influencing the distribution pattern of moss crusts are complex and contain the soil factor, current climatic conditions and natural and human disturbances.
5

Effects of environmental variation and spatial distance on the beta diversity of woody plant functional groups in a tropical forest

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Zhang Z., Zang R., Wang L., Wang G., Zhang J.
Polish Journal of Ecology
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2012
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tom 60
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nr 3
Tropical forests are among the most complex ecosystems on Earth. The high alpha-diversity of tropical forests has been amply documented, however, beta diversity, equally important for us to understand the mechanism of biodiversity maintenance, has seldom been studied. The main current hypotheses about the origin of beta diversity are as follows: (1) species composition is uniform over large areas; (2) species composition fluctuates in a random, auto-correlated way emphasizing spatially limited dispersal; (3) species composition is related to environmental conditions. Testing these hypotheses is important to understand ecosystem function and to manage ecosystems effectively. In this study, we quantified the relative influence of environmental variation and spatial distance on the beta diversity of woody plant functional groups in a tropical forest of Hainan Island, China. Floristic and environmental data were collected from 135 grid-sample plots. We classified woody plant functional groups based on frequency, growth forms and successional status, respectively. To see whether environmental variation and spatial distance influence beta diversity, the simple and partial Mantel tests, in conjunction with linear and spline regression models were performed. The results showed that environmental heterogeneity and spatial distance were the primary determinants of pair-wise species composition differences between plots in the study area. Common, tree and climax species were more sensitive than the others to changes in environmental heterogeneity and spatial distance. Except for rare, pioneer and shrub species, the others had apparently negative relationship between spatial distance and similarity. The distance decay of similarity was determined by joint influences of spatial distance and spatially-structured environmental variables. Spatial distance had the clearest effect on beta diversity at distances <15 km and with the increase in spatial distance, beta diversity was gradually controlled by environmental heterogeneity. This study provides further support for neutral theory and environmental control hypothesis as opposed to uniformly distributed hypothesis.
6

Effects of environmental and spatial heterogeneity on tree community assembly in Baotianman National Nature Reserve, Henan, China

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Jia H.-R., Chen Y., Yuan Z.-L., Ye Y.-Z., Huang Q.-C.
Polish Journal of Ecology
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2015
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tom 63
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nr 2
The debate on species coexistence mechanisms never stops. The niche theory, neutral theory, and negative density dependence mechanism has been attracting considerable attention in recent years, but an integrated research on species coexistence mechanisms has rarely been conducted. In this study, a previous investigation at a plot in Henan Province was used as a basis to analyze the spatial structure of the community with principal coordinates of neighbor matrices (PCNM). Variance partitioning was used to analyze the effects of topography, soil, spatial, and stand density on species distribution. Results show that the community structure in the broad, medium, and fine scales generally showed a highly significant spatial structure. Topography, soil, spatial variables, and stand density explained 3.4, 11.7, 12.1 and 19.49% of species distribution, respectively. The aforementioned results suggest that spatial factor was an important factor that affects community structure. Species distribution was evidently influenced by environmental spatial heterogeneity. It had a very important function for density-dependent effects acting on species distribution. Niche theory, neutral theory, and negative density dependence mechanisms affected community building in different degrees.
7

Plasticity to an irradiance gradient in foliage attributes of a perennial monocot Iris pumila [L.]: Comparison of populations from habitats of contrasting light conditions

100%
Avramov S., Tucic B.
Polish Journal of Ecology
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2006
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tom 54
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nr 3
Magnitude and variation in leaf plasticity were quantified in two Iris pumila (L.) populations from habitats of contrasting light conditions (open dune vs wood understorey) at three light intensities (high – 110, medium – 65, and low – 29 μmol m⁻² s⁻¹). Siblings developed from hand-pollinated seeds from 13 and 15 clonal genotypes in an open and a shaded population, respectively, raised in a growth-room were scored for morphological (leaf number, leaf area, specific leaf area), anatomical (stomatal density, leaf thickness, vascular bundle number, sclerenchyma and cuticle widths) and biochemical (chlorophyll content, chlorophyll a:b ratio) traits. Morphological traits in general and SLA (projected leaf area per unit leaf dry mass) in particular were more sensitive to variation in light conditions than any other examined leaf attribute, indicating their key importance for maximizimg light-energy interception at low irradiance. Regardless of the population origin, the average plasticity (percentage trait change between two successive treatments) of morphological traits declined with decreasing irradiance, opposite to anatomical traits, particularly leaf thickness, which increased parallel to light intensity decrease. Mean plasticity variation (across-family CV) changed with light level, ranking in the following order morphological
8

Intra-versus inter-population variation of cone and seed morphological traits of Pinus tabulaeformis Carr. in Northern China: impact of climate-related conditions

80%
Ji M., Zhang X., Wang Z., Zhang Q., Deng J.
Polish Journal of Ecology
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2011
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tom 59
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nr 4
Morphological traits of conifer species are known to vary adaptively with the geographic and climatic variables, but little is known about intra- and inter-population variation and impact of associated climate factors on the morphological variation. Chinese hard pine (Pinus tabulaeformis Carr) is a major and widespread component of coniferous forests in the temperate and semi-humid zone in northern China. Here we investigated 12 life history traits involving cone length (CL), width (CW) and dry weight (CDW), cone length to width ratio (CLW ), seed length (SL ), width (CW) and total weight (STW ), seed length to width ratio (SLW ), seed wing length (SWL), width (SWW) and total weight (SWTW ), seed wing length to width ration (SWLW ) at 12 sites between longitudes (102oE to 122oE) and latitudes (32oN to 43oN) covering an altitude range of 125–2581 m. Our results showed that each morphological character presented a large variation both within and among populations. Moreover, we found that proportion of phenotypic variation (i.e. Vst, %) of the all cone traits except for the cone width was over 50% among populations, indicating that the variation of these traits was mainly controlled by the environmental variables. Although the mean proportion of phenotypic variation of all measured traits was only about 28% among populations of this species, it was much higher than those of other conifers, which further suggested that this species held the higher adaptive phenotypic variation or stress-tolerance ability under varying environmental conditions. Furthermore, the phenotypic variation presented a general pattern that almost all measured traits were negatively correlated with the potential evapotranspiration which reflected the synthetic effects of multiple factors such as the temperature and rainfall, rather than a single environmental or climatic factor. In conclusion, according to the relationship between phenotypic variation and climate factors, it will undoubtedly provide important information for the reforestation and genetic conservation for this species in the changing climate.
9

Environmental heterogeneity controls organic-matter dynamics in river-floodplain ecosystems

80%
Langhans S. D., Tiegs S. D., Uehlinger U., Tockner K.
Polish Journal of Ecology
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2006
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tom 54
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nr 4
Environmental heterogeneity is a key regulator of ecological processes. Riverine floodplains are particularly heterogeneous and dynamic systems and loss of their natural environmental heterogeneity and dynamism as a consequence of human impacts constitutes their most serious threat. On river floodplains, flow and flood pulses create a shifting mosaic of channels, ponds, bars, islands, and riparian forest patches. Composition and spatial arrangement of these habitat patches determine their degree of connectivity, which in turn controls the flux of matter and energy among adjacent patches. In light of these attributes, riverine floodplains are model ecosystems for studying the effect of heterogeneity on ecological processes. In this article we introduce a conceptual model for river-floodplain ecosystems that unifies leaf decomposition, organic-matter input, storage and quality, and stresses the importance of the flow and inundation regime. In combining these aspects of organic matter dynamics, which have been treated separately in the ecological literature, this model fosters a more holistic perspective of ecosystem processes on riverine floodplains. We conclude that the linkage between natural heterogeneity and ecosystem processes needs to be considered in future river-floodplain restoration projects.
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