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1

Environmental determinants of mangrove vegetation structure as revealed by regression analysis

100%
Ukpong I. E.
Polish Journal of Ecology
|
2002
|
tom 50
|
nr 1
The aim of the study was to analyze the mangrove vegetation in relation to environmental factors with a view to offering explanations for variations in the structural characteristics of the mangroves. Multiple regression analysis was used as the analytical tool to predict vegetation response to the environment. Salinity, soil magnesium and bulk density were the most important determinants of overstorey mangrove structure while tidal flood, exchangeable cations and topography were important in the understorey. The groundlayer stratum was determined by substrate texture, tidal flood and topography.
2

Impact of humic substances on the structure of the vegetation of hardwater lakes

100%
Bociag K.
Publications of the Department of Plant Taxonomy of the Adam Mickiewicz University in Poznan
|
2000
|
tom 10
3

Structure and dynamic trends of plants communities in the Pogubie Male Lake system

86%
Sikorski P.
Annals of Warsaw Agricultural University. Horticulture (Landscape Architecture)
|
2002
|
tom 23
4

Tendencies of changes in the flora and vegetation structure of Pomeranian lakes under the influence of humic substances

86%
Szmeja J.
Publications of the Department of Plant Taxonomy of the Adam Mickiewicz University in Poznan
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2000
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tom 10
5

Chosen traits of structure of vegetation landscapes resulting from natural conditions and from human impact [Case study of Pojezierze Miedzychodzko-Sierakowskie]

86%
Wojterska M.
Publications of the Department of Plant Taxonomy of the Adam Mickiewicz University in Poznan
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2000
|
tom 10
6

Spider assemblages of hummocks and hollows in a primeval alder carr in the Białowieza National Park – effect of vegetation structure and soil humidity

72%
Stanska M., Stanski T., Gladzka A., Bartos M.
Polish Journal of Ecology
|
2016
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tom 64
|
nr 4
We studied the species richness, diversity, abundance and guild composition of spider assemblages on the hummocks and in the hollows of the alder carr in the Białowieża National Park. We also assessed the effect of vegetation structure and soil humidity on spiders settled in these two microhabitats. The spiders were collected from 10 May until 27 October 2001 by pitfall trapping. The main factor which differed between the hummocks and the hollows was soil humidity. In the case of vegetation cover we found some differences between the microhabitats but it was particularly evident in the case of litter, which was higher on the hummocks. Spider species diversity was significantly higher on the hummocks than in the hollows, but the number of individuals captured in both microhabitats was similar. The collected spiders belonged to six guilds and the proportion of spider individuals in particular guilds was significantly different between the hummocks and the hollows. The most abundant guild in both microhabitats was ‘ground hunters’ and the most numerous species was Piratula hygrophila. Our analyses showed that soil humidity positively affected the number of spider species and the number of individuals. Sampling date strongly influenced the number of collected species and spider individuals. Vegetation and litter cover did not have a significant impact on the spider assemblages. Our findings suggest that research conducted only on hummocks in the alder carr does not reveal the real structure of spider assemblages.
7

Home range and habitat use by Aquatic Warblers Acrocephalus paludicola on their wintering grounds in Northwestern Senegal 

72%
Arbeiter S., Tegetmeyer C.
Acta Ornithologica
|
2011
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tom 46
|
nr 2
The Aquatic Warbler Acrocephalus paludicola was once a common breeding bird in mesotrophic fen mires all over Central and Western Europe. In the last century large parts of its habitat have been destroyed by wetland drainage and agricultural intensification. Besides protecting the remaining breeding habitats, it is of great importance to preserve suitable migration stopover habitats and wintering grounds to avert the extinction of the species. We determined home-range size and the use of vegetation associations of Aquatic Warblers on the wintering grounds in a flooded plain north of the Djoudj National Park in Senegal. Individual birds (11) were caught in mist nets and equipped with radio transmitters. Locations were assessed by radiotelemetry and a compositional analysis was conducted to determine which vegetation types were preferred within home ranges. Similar to their behaviour on the breeding grounds, the Aquatic Warblers showed no territorial behaviour in their winter quarters. They used home ranges that averaged 4 ha in size, which they shared with conspecifics and other warblers. The home ranges overlapped 54% on average, with a maximum of 90% in an area used by four individuals. The vegetation structure of the wintering habitat is similar to breeding grounds and stopover sites of the species. Preferential vegetation had 80% to 100% cover and consisted of 60 to 90 cm high stands of Oryza longistaminata, Scirpus maritimus or Eleocharis mutata. Most birds stayed more often near the edge of open water, probably for foraging. A constant inundation seems essential, because Aquatic Warblers never occurred in desiccated parts of the study site.
8

Selection of foraging habitat by grassland birds: effect of prey abundance or availability?

72%
Romanowski J., Zmihorski M.
Polish Journal of Ecology
|
2008
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tom 56
|
nr 2
365-370
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.
9

The influence of vegetation structure on the composition of the seed rain and seedling pool in abandoned Molinion caeruleae meadows

72%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 2
The investigations of the effect of different habitat conditions on the composition of the seed rain and seedling pool were conducted in the years 2014 and 2015 in abandoned patches of Molinion caeruleaedominated by small-stature meadow taxa (patch I), tall-growing grasses (patch II), as well as shrubs and trees (patch III). Observations showed that along the successional gradient the seed rain and seedling pool diminishes. The prevalence of perennials and native taxa in the seed rain and seedling pool occurred in all the study sites. Moreover, in the propagule and seedling pools of all the patches hemicryptophytes and meadow taxa prevailed but their number decreased in successional sites. Also, the abundance of ruderal and grassland taxa decreased gradually, at expense of number of forest species. Zoochorous species prevailed in the seed rain and seedling pool of all patches. Number of hydrohorous species decreased in successional patches, while the abundance of species with other dispersal modes were similar. Irrespective of patch character, the species producing propagules with medium size dominated in the seed rain and seedling pools, whereas a significant decrease of number of small-seeded species was noticed only in the seedling pool. Despite the diminishing of the seed rain and seedling pool along the successional gradient, the gap creation might be a very effective way of active protection of Molinion caeruleae meadows. However, the gap colonisation requires permanent monitoring to avoid further spreading of undesired taxa.
10

A comparison of two European breeding habitats of the Water Rail Rallus aquaticus

72%
De Kroon G. H. J.
Acta Ornithologica
|
2004
|
tom 39
|
nr 1
The study was carried out in two sites — fluvial mires (FM) in Netherlands, and at salt marshes (SM) and at the borders of lagoons (BL) in Spain. All 58 nests were found in unmown and ungrazed vegetation. Carex species were dominant at the nesting sites FM, but not Phragmites australis. Juncus maritimus was dominant in the SM and at the BL. The plant communities at and around the nest sites of FM differed from those of SM + BL. At nest height from the side the nest was mostly only poorly visible. Nests at nest height and eggs at observer eye level were invisible among dense clusters of Juncus maritimus tussocks. Visibility of eggs in reed stands mixed with Carex species and in Sparganium erectum stands was mostly poor and moderate respectively. This was in contrast to nests situated among Juncus maritimus stems. For the most part, an incubating Water Rail on the nest at eye-level was hardly visible in any of the various stands. The vegetation height of nest sites in SM and BL was considerably less than in FM owed to the absence of Phragmites australis. The nest height in tussocks of Juncus maritimus was greater. The other nests characteristics (diameter, depth and weight) were not significantly different in FM and SM + BL. The nest material corresponded to the plant species in the immediate vicinity of the nest.
11

Habitat preferences of the bank vole Myodes glareolus in a Mediterranean mountain range

72%
Torre I., Arrizabalaga A.
Acta Theriologica
|
2008
|
tom 53
|
nr 3
The bank voleMyodes glareolus Schreber, 1780 is a widely distributed rodent in Europe, being numerically dominant in small mammal communities living in temperate woodlands. However, it becomes scarce in southern Europe (Mediterranean area) where it reaches the southernmost limit of its distribution range. We studied the habitat preferences of bank voles in 9 plots in a transitional area between Mediterranean and Eurosiberian regions within a Mediterranean mountain. During the study period we captured 1919 small mammals of 9 species, including 287 bank voles (14.95%). Mean density ranged from zero individuals per plot (1.1 ha) at the boreo-subalpine scrubland to 10.27 ± 2.84 (SE) at a Mediterranean river woodland. Statistical path analysis was used to investigate relationships between mean bank vole density and climate and vegetation structure measured within plots. The variables selected by the structural equation model were those related to forest structure, like tree cover and height, dead vegetation, moss, and rock cover. Habitat moisture was also important (microclimatic conditions). Mean climate conditions (and elevation) did not have any significant effect on mean bank vole density, and no significant association with understorey vegetation (eg shrub and herbaceous cover) was observed. Our results pointed out that bank voles were habitat specialists in our study area, being more abundant and frequent in moist woodlands, and rare or absent in shrublands and grasslands.
12

Comparison of some characteristics of Polish and Hungarian arable fields vertical structure of the vegetation and weed cover as possible factors contributing to the population decline of the great bustard [Otis tarda]

72%
Takacs V.
Animal Science. Scientific Papers of Agricultural University of Poznan
|
2002
|
tom 04
13

Vegetation structure and composition of road verge and meadow sites colonized by Cabrera vole [Microtus cabrerae Thomas]

72%
Santos S. M., Mathias M., Mira A., Simoes M. P.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 3
This paper analyses the floristic composition and vegetation structure in road verge and meadow sites colonized by Cabrera vole (Microtus cabrerae Thomas, 1906), a threatened rodent with fragmented distribution in the Iberian Peninsula. Vegetation was sampled in 26 colonized patches in five geographical areas of Southern Portugal. The cover of the herbaceous layer was sampled in 1 × 1 m plots. Several variables related to plant diversity, Raunkiaer lifeforms, taxonomic groups, disturbance and soil properties were assessed. Floristic composition of the herbaceous communities of road verge and meadow sites was different. Indicator species of road verges corresponded mainly to annual grasses and forbs, ruderal and nitrophilous species, along with a few perennials. In meadows, perennial grasses and moisture indicative species were more common. Results suggest that road verges are lower quality habitats for Cabrera vole maintenance, due to high disturbance, low moisture availability during summer and reduced patch surface. Nevertheless, they might provide benefits such as extra foraging and refuge, especially in disturbed areas. Potential ecological effects of road verge management are discussed in the light of species conservation goals.
14

Scots pine [Pinus sylvestris] ecosystem response to climate on a temperate to boreal forest transect: project description

72%
Reed D., Breymeyer A., Degorski M., Noble R.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
This brief paper describes the history and conceptual framework underlying the research presented in the remaining papers in this volume. This project began in 1996 as an international effort to examine Scots pine (Pinus sylvestris) ecosystem structure and function in one of the few accessible areas on earth where similar forested ecosystems exist over a 20° range in latitude. Widely predicted climate warming leads to serious concerns about how ecosystems may respond to stresses created by climate change. In order to recognize evidence of warming and to predict likely future responses, it is necessary to understand how ecosystems that are distributed along climatic gradients accommodate wide climatic differences. Few tree species are distributed as widely as Scots pine, which ranges over much of Europe. This species is ideal for investigations that address questions regarding climate change effects on forest ecosystem structure and processes. Its distribution over comparable sites extending from temperate to boreal zones (over more than 20° of latitude from northern Finland to southern Poland) permits characterization of this ecosystem over a relatively wide climatic range (covering a mean annual temperature difference of 9°C). This transect: 1) provides information concerning numerous ecological processes over this wide range of conditions; 2) serves as a template for the development, testing, and evaluation of specific ecological indicators related to climate change; and 3) allows evaluation, comparison, and projection of ecological properties and processes among similar ecosystems with varying climate.
15

Vegetation structure and ecological characteristics of forest of North Andaman Islands (India)

58%
Prasad P. R. C., Sringeswara A. N., Reddy C. S., Kumari P. V., Varalakshmi R. K., Raza S. H., Dutt C. B. S.
Biological Letters
|
2009
|
tom 46
|
nr 2
16

The influence of co-occurring vegetation and habitat variables on distribution of rare charophyte species Lychnothamnus barbatus (Meyen) in lakes of Western Poland

58%
Gabka M., Owsianny P. M., Burchardt L.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 1
At present Lychnothamnus barbatus (Meyen) Leonhardi belongs to the rarest species of charophytes in the world. In Europe it is classified as threatened with extinction. The problem of extinction of this species is intriguing, in particular in the context of its widespread occurrence in Europe and Asia till the last decade of the 20th century. Records of L. barbatus from Wielkopolska region (Western Poland) are know from 15 lakes. The most of them was stated in 19th and on beginning of 20th centuries. Now, this species is growing in 6 lakes, from among 2 sites are new. This study was undertaken to a) determine the abundance of L. barbatus and the co-occurring plant species at different sites in lakes, b) determine the most important ecological parameters controlling the structure communities with L. barbatus co-occurring and quantitative responses of this species. In 7 lakes (area 5.5-197 ha, depth max. 7.8– 38 m, trophic state: meso-eutrophic) in western Poland the species composition and coverage of vegetation were studied at the 23 plots with L. barbatus occurrence in relation to the measured variables. Seventeen environmental parameters were measured including: depth of water, pH, conductivity, SO₄²⁻, NH₄⁺, NO₃⁻, PO₄³⁻, Na⁺, K⁺, Ca²⁺, Mg²⁺, chlorophyll a, Secchi disc visibility, colour, O₂ dissolved, saturation, total Fe during the period July–September. The DCA and CCA analyses were used to assess the relation between vegetation parameters and environmental variables. L. barbatus preferred the water rich in Ca⁺, Mg²⁺ and SO₄²⁻ and with high concentrations of nutrients, especially NH₄⁺ and PO₄³⁻, and moderate values of electrolytic conductivity. In the studied lakes, L. barbatus occupied the separate niche. This species formed the communities in very shallow marginal zones of lakes (0.4–1.5 m) with other macrophytes like: Chara vulgaris, C. tomentosa, Potamogeton ´ nitens, and monospecific stands on margins of steep lake slopes (4–6 m) with Chara globularis fo. hedwigii and Nitella mucronata. The process of extinction of this species seems to be related with increasing turbidity related in turn to algal blooming in lakes and with the spatial competition of vascular macrophytes, especially Ceratophyllum demersum.
17

Forecasting carbon budget under climate change and CO2 fertilization for subtropical region in China using Integrated Biosphere Simulator (IBIS) model

58%
Zhu Q., Jiang H., Liu J., Peng C., Fang X., Yu S., Zhou G., Wei X., Ju W.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 1
The regional carbon budget of the climatic transition zone may be very sensitive to climate change and increasing atmospheric CO2 concentrations. This study simulated the carbon cycles under these changes using process-based ecosystem models. The Integrated Biosphere Simulator (IBIS), a Dynamic Global Vegetation Model (DGVM), was used to evaluate the impacts of climate change and CO2 fertilization on net primary production (NPP), net ecosystem production (NEP), and the vegetation structure of terrestrial ecosystems in Zhejiang province (area 101,800 km2, mainly covered by subtropical evergreen forest and warm-temperate evergreen broadleaf forest) which is located in the subtropical climate area of China. Two general circulation models (HADCM3 and CGCM3) representing four IPCC climate change scenarios (HC3AA, HC3GG, CGCM-sresa2, and CGCM-sresb1) were used as climate inputs for IBIS. Results show that simulated historical biomass and NPP are consistent with field and other modelled data, which makes the analysis of future carbon budget reliable. The results indicate that NPP over the entire Zhejiang province was about 55 Mt C yr-1 during the last half of the 21st century. An NPP increase of about 24 Mt C by the end of the 21st century was estimated with the combined effects of increasing CO2 and climate change. A slight NPP increase of about 5 Mt C was estimated under the climate change alone scenario. Forests in Zhejiang are currently acting as a carbon sink with an average NEP of about 2.5 Mt C yr–1. NEP will increase to about 5 Mt C yr–1 by the end of the 21st century with the increasing atmospheric CO2 concentration and climate change. However, climate change alone will reduce the forest carbon sequestration of Zhejiang’s forests. Future climate warming will substantially change the vegetation cover types; warm-temperate evergreen broadleaf forest will be gradually substituted by subtropical evergreen forest. An increasing CO2 concentration will have little contribution to vegetation changes. Simulated NPP shows geographic patterns consistent with temperature to a certain extent, and precipitation is not the limiting factor for forest NPP in the subtropical climate conditions. There is no close relationship between the spatial pattern of NEP and climate condition.
18

Influence of vegetation structure on the small mammal community in a shortgrass prairie ecosystem

58%
Thompson C. M., Gese E. M.
Acta Theriologica
|
2013
|
tom 58
|
nr 1
The structure of vegetation, and how this structure varies across a landscape, is crucial to understanding the distribution of wildlife species. Between 2002 and 2004, we sampled small mammal communities and measured vegetation structure at 185 locations across a range of disturbance regimes in a shortgrass prairie ecosystem in southeastern Colorado, USA. At each sampling location, the local disturbance regime was some combination of varying intensity of livestock grazing, military training activity, and fire. Vegetation structural characteristics measured included percent bare ground, basal cover, litter, shrub density, and mean grass and shrub height. Rodent communities were described by richness, diversity, total and per capita biomass, and species abundances. Northern grasshopper mice (Onychomys leucogaster), Ord's kangaroo rats (Dipodomys ordii), silky pocket mice (Perognathus flavus), western harvest mice (Reithrodontomys megalotis), white-footed mice (Peromyscus leucopus), southern plains wood rats (Neotoma micropus), thirteen-lined ground squirrels (Spermophilus tridecemlineatus), deer mice (Peromyscus maniculatus), and spotted ground squirrels (Spermophilus spilosoma) accounted for >99 % of all captures. Canonical correlation analysis was used to assess the relationship between small mammals and vegetation structure. The first two canonical variates explained over 50 % of the variation in vegetation structure and were related to the ratio of bare ground to basal coverage and litter accumulation. Rodent community indices were most strongly related to litter accumulation and shrub density, though the models had low explanatory power. Our results agreed with published findings regarding microhabitat associations and indicated small mammal communities benefited from a system of interacting disturbances and the resulting landscape mosaic.
19
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Vegetation structure in Shahbazgari, District Mardan

58%
Khan M., Hussain F., Musharaf S.
International Letters of Natural Sciences
|
2015
|
tom 39
The present work was made to investigate the vegetation structure of shrubs and herbs in research area. Total 48 plant species consisting of 7 shrubs and 41 herbs constructing Cenchrus- Zizyphus-Saccharum community from 9 sites in which 9 communities i.e. Fumaria-Rumex- Xanthium community, Cynodon-Solanum-Sonchus community, Cynodon-Sorghum-Alhagi community, Ajuga- Malvastrum-Calotropis community, Cynodon –Convolvulus-Cyperus community, Ajuga-Saccharum-Chenopodium community, Alhagi-Rumex-Euphorbia community, Saccharum-Cannabis-Xanthium community and Achyranthus-Ajuga-Euphorbia community were found. The contribution of total important values by shrubs was 43.78 and 256.2 by herbs. The soil of the area had better calcium carbonate in the range of (11.72 – 12.99 %), with soil pH (6.45 – 8.11). The EC was found in the range of (0.13-0.22 dS m-1). The concentrations of P and K content were found in the range of (3.54-3.92 mg Kg-1) and (111.21-127.14 mg Kg-1). These results highlight the constant need for long-term ground-based conservation monitoring in combination with satellite-based monitoring of changes in vegetation cover.
20

Factors affecting bird species diversity on a local scale: a case study of a mosaic landscape in Southern Poland

58%
Tworek S.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 4
The main objective of this paper was to investigate factors that affect bird species diversity at local spatial scales including the role of habitat heterogeneity. The studies were carried out in a mosaic landscape of southern Poland, in habitat fragments, each described by variables which characterised the size of the plot and its spatial structure, including vegetation. A species diversity index was then calculated for each plot using Shannon-Wiener index, based on count of nesting birds obtained through territory mapping method. Correspondence analysis (CA) was then used to illustrate relationships between groups of plots of different scopes of species diversity and the measured characteristics of the plots. The high diversity among birds was found to be primarily connected with an increase in the proportion of old forest, whereas the diversity decreased with an increase in the proportion of ‘farmland’ (including meadows and pastures). Other significant effects on the changes in species diversity were exerted by the degree of density in the herb layer and the tree canopy layer, as well as by the presence of wetlands. The localscale inertia in the heterogeneous-type habitats results primarily from the differences in quality and structure of the plot, which reflect their position between the ‘forest’ – ‘non-forest’ gradient. In the studied range of sizes (0.2–40 ha), the size of a given plot is of lesser significance than that of the vegetation structure. All the variables which represent potential effects upon the local-scale diversity of birds, and the suitability of CA are discussed against the background of the results of this study and available literature data.
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