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1

Use of siliceous algae as biological monitors of heavy metal pollution in three lakes in a mining city, Southeast China

100%
Chen X., Mao X., Cao Y., Yang X.
Oceanological and Hydrobiological Studies
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2013
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tom 42
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nr 3
2

Vascular plants versus mosses in lakeland and riverine mires in two regions of Eastern Poland

80%
Sugier P., Czarnecka B.
Polish Journal of Ecology
|
2010
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tom 58
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nr 4
Our research was conducted in two different mire habitats – in the minerotrophic and ombrotrophic mires adjoining the lakes (LM) of the Łęczna-Włodawa Lakeland and in the eutrophic and calcium-rich mires of the river valleys (RM) of the Roztocze Highlands region (both study regions in Eastern Poland). The study aimed to evaluate (1) the position of mire phytocoenoses in the environmental gradient – from minerotrophic to ombrotrophic ones, (2) the influence of the species and life-form composition of plant communities on the density of bryophytes, and (3) the quantitative and sociological relations between the density of vascular plants and bryophytes. Phytosociological relevés (180) were made in six lakeland mires and in four river valleys. The area of each phytosociological relevés (16–25 m²) represented species composition and vertical structure of communities. In the study of the relation vascular plants-bryophytes we took into consideration the following parameters: species abundance, cover of particular plant layers (trees, shrubs, herbs, bryophytes), and the number of species in particular life-form groups. In the LM the cover of particular layers was correlated negatively with the abundance of Sphagnum mosses. Betula pendula, B. pubescens and Frangula alnus overgrowing the LM affect negatively the abundance of some peat mosses. Less distinct relations were found between the tree density and bryophyte cover in the RM, but there is a positive correlation between the shrub cover and its predominant species – F. alnus – and the abundance of Polytrichum commune. Taking into account the relations between the herbaceous cover and the abundance of bryophytes, the dependencies are also less pronounced in the RM phytocoenoses. A negative effect of the herbaceous cover and its species richness on the abundance of P. commune was observed, as well as positive relation between the number of herbaceous species and the abundance of Calliergonella cuspidata. In the LM phytocoenoses, a negative correlation was found in the case of S. palustre, while in the case of Aulacomnium palustre and S. cuspidatum the relations were positive. Among herbaceous plants of LM habitats the biggest number of statistically significant correlations were observed for abundance of Carex lasiocarpa and different bryophytes, while in the RM habitats the correlations between the abundance of bryophyte and vascular plant layers are less distinct.
3

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

80%
Jakubas E., Gabka M.
Oceanological and Hydrobiological Studies
|
2015
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tom 44
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nr 2
4

Factors determining the distribution of rheophil and protected Hildenbrandia rivularis (Liebmann) J. Agardh 1851, the Rhodophyta freshwater species, in lowland river ecosystems

80%
Jakubas E., Gabka M., Joniak T.
Polish Journal of Ecology
|
2014
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tom 62
|
nr 4
The relationships of Hildenbrandia rivularis (Rhodophyta), the species composition of its surroundings detailed environmental variables (water chemistry and hydrological, morphological and bottom features) in a lowland river (Wełna river, Western Poland) was investigated. H. rivularis from 40 stands was tested together with 25 environmental variables and vegetation. Detrended correspondence analysis (DCA) and redundancy analysis (RDA) were used to describe the relations between the species composition and the selected variables. The uniqueness of this protected species is an ability of formation incrustation on rocks but also coexistence with two groups of species: other algae and vascular plants. In study twenty-two plant taxa were recorded in 40 vegetation plots, including 4 macroscopic algae, 2 mosses and 16 vascular plants. The most common H. rivularis co-occurred with Leptodictyum riparium, Fontinalis antipyretica and Nuphar lutea. Most of the studied plots with red algae were characterised by shallow water and strong water velocity. H. rivularis prefers alkaline water with high conductivity. The results of the RDA, after forward selection, demonstrated that pH gradient, optical features such as dissolved organic matter and water colour – control the variation in the floristic communities with H. rivularis.
5

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

80%
Bosiacka B., Kull T., Wieclaw H., Marciniuk P., Podlasinski M.
Polish Journal of Ecology
|
2016
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tom 64
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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).
6

Numerical analysis of bryophyte - environment relationships in a lowland English flora

80%
Bates J. W.
Fragmenta Floristica et Geobotanica
|
1995
|
tom 40
|
nr 1
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