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1

Relations between morphometric and trophic parameters of shallow lakes of the Polish lowland

100%
Staniszewski R., Jusik S., Hryc-Jusik B.
Nauka Przyroda Technologie. Uniwersytet Przyrodniczy w Poznaniu
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2009
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tom 03
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nr 2
2

Changes in species composition of an abandoned limestone grassland in relation to climatic conditions

84%
Dzwonko Z., Loster S.
Polish Journal of Ecology
|
2011
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tom 59
|
nr 4
After abandonment many species-rich limestone grasslands have been overgrown by tall grasses and forbs, and often by shrubs and trees. As a result, communities with many regionally rare and endangered species are vanishing. We examined to what extend changes in the cover of sociological species groups and plant functional types in an unmanaged grassland depend on fluctuations in climatic conditions. Vegetation data from permanent plots in an abandoned grassland in southern Poland collected over 12 years were used. Relations between weather variables, time, and the cover of species groups were analysed using multiple linear regression and canonical correspondence analysis (CCA). The climatic data included mean temperatures and precipitation sums for each month from January to December (for the current year from January to July), and for 2, 3 and 4 consecutive months, with time lags of 0, 1, 2 and 3 years. It was found that both inter-annual fluctuation of climatic conditions and successional processes considerably influenced species composition of the study grassland. The fluctuations in precipitation and temperature explained from 0.8% to 27.1% of the variation in the cover of various sociological groups. The greatest effect on the cover dynamics of all species and majority of sociological groups had precipitation in spring and early summer in the current year. Most of species groups were affected also by temperature in spring and/or summer in the previous years, but its effect as lower than precipitation. The obtained results suggest that climatic conditions have also a significant impact on the rate of changes in abandoned limestone grasslands. Higher precipitation in spring and summer favour growth and spread of tall meadow grasses and forbs, accelerating changes from less compact communities dominated by smaller xerothermic species to more compact vegetation with a closed structure. In consequence the role of xerothermic calcareous species decreases and many of them may locally extinct within decades.
3

Positive grass diversity-productivity relationships and controlling factors along an elevation gradient in Central Asian Alpine grasslands

84%
Li K., Fangmeier A., Hu Y., Liu X.
Polish Journal of Ecology
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2012
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tom 60
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nr 1
The productivity-diversity relationship in grasslands is of great interest with regard to species loss in natural ecosystems, where species extinction is not random but directed. We carried out a three-year investigation from 2005 to 2007 along an elevation gradient in alpine grasslands of Central Asia in an area of 70 x 20 km2 at Bayinbuluk, Tianshan Mountains. We selected 9 sites (10 x 10 m2) and 117 plots (1 x 1 m2) from 2460 to 3260 m a.s.l. with 100 m intervals of altitude. Species richness, productivity, soil characteristics, air temperature and relative humidity (May–August) were recorded. The relationship between plant diversity and productivity was significant and positive. We used ordination techniques such as Canonical Correspondence Analysis (CCA) to examine the relationship between vegetation and the environmental factors. The results showed that plant species composition, species richness and productivity were significantly affected by air temperature, soil pH and relative humidity across the study area.
4

Diversity, spatiotemporal distribution, abundance, species composition and habitat preferences of Ostracoda in Akbuk and Akdeniz coastal mesosaline lagoons (Mugla, the South Aegean Region, Turkey)

84%
Altinsach S., Percin-Pacal F., Altinsach S.
Oceanological and Hydrobiological Studies
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2015
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tom 44
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nr 2
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Effect of physicochemical parameters on zooplankton in the brackish, coastal Vistula Lagoon

84%
Paturej E., Gutkowska A., Koszalka J., Bowszys M.
Oceanologia
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2017
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tom 59
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nr 1
This paper analyzes whether physicochemical properties significantly influence the occurrence of zooplankton in a brackish reservoir. The studies were carried out on the Vistula Lagoon in August and September from 2006 to 2009 at 32 research sites. The environmental conditions in the Vistula Lagoon varied widely. At the time of the investigation, 17 species of rotifers, six species of Cladocera, and ten species of Copepoda were noted, and the total density of plankton fauna ranged from 145 to 765 ind. dm3. Statistical analysis demonstrated a significant correlation between the occurrence of some zooplankton species and certain environmental parameters, whereas the sampling sites were grouped according to study years. The zooplankton systems recorded at the research sites in 2006 constitute the most disparate group. Thus, it can be concluded that physicochemical properties might significantly impact both individual species (depending on their environmental demands) and entire zooplankton clusters.
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The advanced statistical methods in aerobiological studies

84%
Grinn-Gofron A., Bosiacka B.
Acta Agrobotanica
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2012
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tom 65
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nr 4
Pollen and spore forecasting has become an important aim in aerobiology. The main goal is to provide accurate information on biological particles in the air to sensitive users in order to help them optimize their treatment process. Many statistical methods of data analysis are based on the assumptions of linearity and normality that often cannot be fulfilled. The advanced statistical methods can be applied to the problems that cannot be solved in any other effective way, and are suited to predicting the concentration of airborne pollen or spores in relation to weather conditions. The purpose of the study was to review some advanced statistical methods that can be used in aerobiological studies.
7

Effects of coastal upwelling on picophytoplankton distribution off the coast of Zhanjiang in South China Sea

84%
Wu M.-L., Wang Y.-S., Wang D.-X., Dong J.-D.
Oceanological and Hydrobiological Studies
|
2014
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tom 43
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nr 3
8

Endemic plant species in a karstic canyon [Mediterranean Region, Turkey]: relation to relief and vegetation diversity

84%
Ozkan K., Suel H.
Polish Journal of Ecology
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2008
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tom 56
|
nr 4
709-715
Data collected from 85 sample plots in Yazili Canyon Nature Park (deep, limestone valley; length - 6 km, area – 600 ha, height – 100–400 m) located in Mediterranean region (Turkey) yielded 24 endemic vascular plants. The endemic plant diversity and all vascular plant diversity indices were calculated for each sample plot using Simpson index. Regression analysis was performed between environmental factors, plant diversity and canopy closure. Endemic plant diversity showed a positive correlation with vascular plant diversity, and a negative correlation with slope position and altitude. A significant quadric relationship was observed between the endemic plant diversity and aspect variable. RDA (redundancy analysis) and CCA (canonical correspondence analysis) based on linear regressions were applied to determine the environmental factors affecting the distribution of endemic species, and the best model based on total variance explained was selected. According to RDA based on linear regression, habitat selection of endemics is strongly correlated with aspect, slope position and altitude. Lower altitude zone (300–500 m), the north aspect and lower slope including valley bottom of Yazili canyon were observed to be the most suitable areas for endemics.
9

Effects of some abiotic factors on the occurrence of aquatic mycobiota in lakes of the Drawa National Park

67%
Mazurkiewicz-Zapalowicz K., Silicki A., Gregorczyk A., Biedunkiewicz A., Wolska M.
Oceanological and Hydrobiological Studies
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2012
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tom 41
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nr 4
10

Vascular ground flora in relation to topography, canopy structure and gap light regimes in a subtropical broadleaved forest (South China)

67%
Ou Y.-D., Su Z.-Y., Ke X.-D., Li Z.-K.
Polish Journal of Ecology
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2012
|
tom 60
|
nr 3
We examined the influence of topogra phy, canopy structure and gap light environmental variables on the patterns of vascular ground flora (vascular plants less than 1 m in height excluding tree seedlings) in a subtropical broadleaved forest in S China, using field data obtained from a 4-ha permanent plot. Both topographic and canopy environmental conditions had a significant effect on community composition, species diversity and distribution of the vascular ground flora. However, topographic factors, especially slope position and aspect, had a greater influence as compared with canopy and understory light conditions. Both number of individuals and number of individuals per species of the ground flora varied significantly with different slope position, aspect, slope steepness and transmitted direct radiation, while species richness varied significantly under different slope position and canopy leaf area index (LAI) The effects of topographic and canopy environmental conditions on ground-flora composition and structure was further confirmed by Canonical Correspondence Analysis (CCA). Multi-response Permutation Procedures (MRPP) showed significant differences in the ground-flora species composition based on all the topographic, canopy structure and gap light variables. Species indicative of topographic, canopy structure and gap light regimes were identified with a significant indicator value (IV ≥ 35%) by Indicator Species Analysis (ISA), which indicated that certain species have their ecological preference for a particular environmental gradient.
11

Significance of current velocity gradients for distribution patterns of charophytes versus mosses and vascular plant communities in a lowland stream

67%
Jakubas E., Gabka M.
Oceanological and Hydrobiological Studies
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2015
|
tom 44
|
nr 2
12

Habitat requirements of marsh dandelions (Taraxacum) in Polish and Estonian coastal grasslands

67%
Bosiacka B., Kull T., Wieclaw H., Marciniuk P., Podlasinski M.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 2
Factors determining the distribution of highly endangered marsh dandelion species in Polish and Estonian coastal grasslands have been investigated. The aim of this study was twofold: (i) to determine which environmental variables are responsible for the vegetation patterns in coastal grasslands with marsh dandelion and (ii) to analyse the ecological spectra of the identified marsh dandelion species. Altogether 51 plots were sampled (in 2013 and 2014). They were used following statistical analysis: DCA, CCA, Spearman's rank correlation test, Kruskal-Wallis test and hierarchical divisive cluster analysis (TWINSPAN). In total, three marsh dandelion species were found in Polish and Estonian coastal grasslands. The only species found in Poland was Taraxacum balticum. In Estonia all three species occur: T. balticum, T. decolorans and T. suecicum. Taraxacum balticum has been found in the widest ranges of all soil properties included, usually on organic, saline, non-carbonate and acid to slightly acid substrate. Taraxacum suecicum and T. decolorans have been found only on mineral, non-saline and slightly alkaline to alkaline substrate. The ecological spectra determined for endangered marsh dandelion species can be used to improve the methods of their protection. Nomenclature: mosses - Ochyra et al. (2003); vascular plants - Mirek et al. (2002).
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