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1

The impact of disturbance gradient on recruitment of clonal plant species in Molinietum caeruleae meadows

100%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 3
The investigations of the impact of disturbance severity on recruitment of clonal plant species were preformed in three Molinietum caeruleae patches dominated by small meadow species (MC), or prevailed by tall grasses (GR) or overgrown by willows (SA). The meadows were located in Vistula valley close to Kraków agglomeration, southern Poland. In above menntionned patches ten permanent experimental plots were randomly arranged. Each plot was divided in four subplots measured 900 cm² represented undisturbed control, low level of disturbance (the litter and the moss layer removal), intermediate level of disturbance (the litter, moss and above-ground vegetation removal), high level of disturbance (the litter, moss and the plants removal as well as top soil raking). The colonization of gaps was observed in the years 2008–2010. Irrespective of patch character, the greatest species richness and seedling abundance were observed in gaps, which occurred in result of intermediate disturbances. Weaker recruitment rates were recorded in openings left after disturbances of low- and high severity, while in fully compact herb layer no seedlings were found. In MC patch, regardless of treatment in all openings similar spectra of life history traits were observed. In seedling pool of all subplots appeared taxa creating below ground organs of clonal growth. In all subplots dominated species with intermediate values of lateral spread, numerous vegetative descendants, short-lasting stems and no persistent genet integration. In sites GR and SA in openings left after weak disturbances appeared species with below- and aboveground organs of clonal growth. The majority of them characterized by slight lateral spread, low number of vegetative offsprings, long lifespan of shoots and persistent genet integration. The abundance of taxa creating underground clonal growth organs, with considerable vegetative spread, high production of daughter ramets, short lifespan of shoots and not enduring genet integration increased gradually and significantly with disturbance gradient. Although the greatest recruitment rates were found in gaps left after removal of litter, moss and above-ground parts of plants, the most effective way for conservation of Molinietum caeruleae meadows appeared to be creation of different severity disturbances. Such treatment contributes to maintenance of heterogeneity of clonal species composition, especially in patches in advanced successional stages.
2

Meadows of the Granica complex in the Kampinos National Park [Central Poland]: geobotanical characteristics and protection proposals

100%
Michalska-Hejduk D.
Nature Conservation
|
2001
|
tom 58
3

The variability of selected features of Gladiolus imbricatus L. in relation to successive stages of meadow communities following the mowing cessation

84%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 2
Molinietum caeruleae meadows belong to the most endangered plant communities in Central Europe, nowadays suffering due to the lack of management. The land abandonment promotes strong secondary expansion of macroforbs, sedges or willows, contributing to decrease of the species diversity. In light of these findings very interesting seems to be the evaluation of the variability of features of populations of rare meadow species. In Poland one of strictly protected plant is Gladiolus imbricatus L. It is a tuberous, clonal plant with sword-like leaves and tall stalks bearing purple flowers collected in one-sided inflorescence. The studies of spatio-temporal variability of selected features of subpopoulations of Gladiolus imbricatus were carried out in the years 2009-2011 in Kraków-Kostrze (Southern Poland) in patches of Molinietum caeruleae with different species composition. In Patch I chiefly occurred small meadow species, Patch II was prevailed by shrub willow, Patch III was dominated by tall-growing macroforbs, Patch IV was characterized by substantial share of large-tussock grasses, while Patch V was overgrown by tall rhizomatous grass Phragmites communis. The plant canopy height and ground moisture raised from Patch I, via Patches II, III and IV, to Patch V. Moreover, in all sites the above mentioned parameters increased moderately in consecutive seasons. The decline of abundance of subpopulations observed in the consecutive years and in the successive patches might be caused by a mortality of individuals, a physical damage of tubers, as well as a prolonged dormancy of genets. The structure of developmental stages were similar in consecutive years but differed significantly among Patches. The increasing trend toward senility noted in successive sites could be an effect of lack of microsites suitable for seedling recruitment or absence of vegetative regeneration. The dimensions of leaf blades, flowering stalks and inflorescences remained similar in the subsequent seasons, but they augmented significantly in the successive patches. The length and the width of capsules did not change significantly between seasons and sites. Concluding, it might be assumed, that the perspectives for survivability of subpopulations diminish gradually from Patch I, via Patches II, III and IV to Patch V. Simultaneously, it should be pointed out that prospects for persistence in each place steadily decrease in effect of continuous deterioration of site conditions.
4

Are Deschampsia caespitosa (L.) Beauv. tussocks safe sites for seedling recruitment in the succession of wet meadows?

84%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 4
In stressful and harsh environments, safe sites for seedling recruitment may be created by nurse plants, which accumulate propagules and subsequently facilitate the establishment of individuals. The main goal of the presented studies focused on observations of seedling recruitment in small and large tussocks of Deschampsia caespitosa derived from patches of unmanaged Molinietum caeruleae meadows situated along the successional gradient and dominated by small meadow species (Patch I), by macroforbs (Patch II), or overgrown by trees and shrubs (Patch III). The studies showed that, irrespective of patch character, Serratula tinctoria, Selinum carvifolia, Lysimachia vulgaris and Filipendula ulmaria are among the best colonizers of Deschampsia caespitosa tussocks. The gradual decrease in number of species and offspring abundance along the successional gradient may be connected with a prolonged period of water stagnation accelerating the development of fungal pathogens, a major cause of mortality for buried diaspores. The growing frequency of species present in standing vegetation and the gradually rising contribution of swamp and forest taxa in consecutive patches may be due to the production of non-persistent diaspores by early successional species, as well as reduced seed immigration from neighboring sites. The obtained results included evidence that, regardless of patch character, the percentage of seedlings representing species present in and absent from existing vegetation as well as taxa with various vegetation types is similar in small and large tussocks. Furthermore, in small tussocks, regardless of patch character, anemochorous and hydrochorous taxa dominated, the frequency of endo- and epizoochorous taxa was much lower, while the percentage of species characterized by other modes of diaspore dispersal attained the lowest rates. In large tussocks, anemochorous and epizoochorous species prevailed, the share of endozoochorous and hydrochorous taxa was lower, and the contribution of species characterized by other modes of dissemination was very scarce. On the basis of these studies it might be concluded that, despite the successive decrease of species and seedling abundance, and along with the increase in the recruitment of taxa resident in standing vegetation, especially woody species, the tussocks of Deschampsia caespitosa are reservoirs of meadow species even in advanced successional stages and may play a significant role in the process of long-term species turnover.
5

The influence of neighbouring species on ecological variation of the selected subpopulations of Iris sibirica L.

84%
Kostrakiewicz-Gieralt K.
Biodiversity: Research and Conservation
|
2013
|
tom 32
Ecological variation of the selected subpopulations of Iris sibirica L. were studied in the years 2011-2012, in the abandoned patches of Molinietum caeruleae dominated by small meadow species (Patch I), macroforbs (Patch II), largetussock grasses (Patch III), shrubs (Patch IV), as well as shrubs and trees (Patch V). The abundance of subpopulations and dimensions of aggregations of ramet clusters increased gradually from Patch I to Patch IV and subsequently declined in Patch V. During the whole study period, all subpopulations showed signs of senility due to the absence of individuals in prereproductive stages. The share of generative ramet clusters diminished, while contribution of senile and fragmentised ramet clusters increased substantially in consecutive patches. The dimensions of ramet clusters increased significantly in successive plots and years. The number and height of generative stems and production of flowers and fruits did not show the temporal variability. The abundance of generative stems was considerably lower in the plots dominated by small meadow species, than in the sites dominated by large-tussock grasses, shrubs or overgrown shrubs and trees. Both the height of flowering stems and production of flowers and fruits increased gradually from Patch I, via Patches II, III and IV, to Patch V. The augmentation of flower production might contribute to better visibility of inflorescences for pollinators, whereas an increase in the production of fruits may increase the chances for successful seed dispersal to new sites. This study results show that the I. sibirica subpopulations occurring in the site dominated by small meadow species and macroforbs were in unsatisfactory condition, those inhabiting the sites dominated by large-tussock grasses and shrubs were in a quite good condition, while the subpopulation inhabiting the plot overgrown by shrubs and trees showed the worst condition.
6

The effect of neighbouring plant height, disturbance level and gap size on spontaneous recruitment of large-seeded and small-seeded species in Molinietum caeruleae meadows

84%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 2
The seed size is considered as a key feature, which effects both: colonizing and competitive abilities of species. The disturbance dependent small-seeded taxa are regarded as superior colonists, whereas the large-seeded taxa are considered as best competitors able to survive the competition from adjacent plants and negative effect of litter. The impact of character of standing vegetation, disturbance level and size of gaps on spontaneous recruitment of seedlings of selected light-seeded species (Gentiana pneumonanthe L., Dianthus superbus L.) and heavy-seeded taxa (Serratula tinctoria L., Gladiolus imbricatus L.) were conducted. The investigations were carried out in two areas (A and B). Both of them were consisted of three adjacent patches of Molinietum caeruleae: dominated by small meadow species (labeled MC), prevailed by large-tussocks grasses (labeled GR), and overgrown by willows (labeled SA). In the year 2007, in all patches, ten permanent experimental plots were randomly arranged. In Area A, plots were divided in four square-shaped, neighboring subplots subjected to: no treatment; the removal of litter and moss layers; the removal of litter, bryophytes, and above-ground parts of plants; the removal of litter, moss and the plants, as well as top soil stripping. In the Area B, plots were divided into four subplots measuring from 0.16 m2 to 0.01 m2. In each of them the litter and above-ground part of plant biomass were clipped and removed. The recruitment of seedlings was monitored from 2007 through 2010. In both studied areas, regardless of seed mass, the greatest abundance of seedlings were found in patches MC, and decreased gradually in sites GR and SA. Irrespective of seed size, in subplots where plant cover and litter stayed intact no new genets was noted, moderate appearance of seedlings was observed in subplots without plant necromass, whereas the greatest number of generative progeny was found in subplots without necromass and aboveground parts of plants. The lower abundance of seedlings in subplots without litter, plants and topsoil might have been caused by depletion of seed bank reserves. Moreover, in all patches the number of seedlings of small- and large-seeded taxa increased significantly with augmentation of gap size. In light of performed studies it might be concluded, that the disturbances might play very important role in active protection of studied taxa. The positive impact of disruption diminishes with increasing of plant canopy height. The removal of plant cover and litter contributes to the greatest seedling recruitment but its beneficial effect diminishes with decreasing of opening size.
7

The effect of gaps size on colonization process in Molinietum caeruleae meadows with different habitat conditions

67%
Kostrakiewicz K.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 4
The disturbances defined as an external factor causing biomass removal are a key component of all ecosystems. In phytocenoses with a continuous vegetation cover and a large proportion of perennial plants the fine-scale disturbances create gaps, which are the temporary competitor-free microsites suitable for plant recruitment. The investigations of natural colonization of different size gaps in Molinietum caeruleae meadows were carried out in patches dominated by small species creating delicate, erect or procumbent stems (MC), prevailed by large-tussock grasses (GR), and overgrown by willows (SA). Each patch was represented by ten plots, divided into four square subplots of 0.16 m2, 0.09 m2, 0.04 m2 and 0.01 m2. In each of them the aboveground parts of plants were clipped and removed with the litter. The seedlings recruitment was observed in 2007–2009. The highest species richness in gaps was observed in the MC patch and might be caused by week competition for light from neighbouring plants with delicate, procumbent stems and narrow leaves. The smaller rate of recruitment in SA and GR patches could be caused by overshading willows as well as by the competition from large and dense tussocks of Deschampsia caespitosa and Molinia caerulea. At all patches species richness declined with the decreasing gap size. The developed seedling pool represented both species occurring in the surrounding canopy and such which were not found there. However, their contribution varied between particular patches. Regardless gap size, the MC seedling pool was dominated by species which did not occur in the established vegetation, whereas in GR gaps both groups were represented by similar numbers of taxa and the SA gaps become dominated by species present in the surrounding canopy. Irrespective of patch character, in each subplot the medium-seeded species were represented most abundantly. The recruitment of genets of large-seeded species decreased, while the abundance of individuals of small-seeded taxa increased with the increasing gap size. In the light of the performed study, one might suggest that extent-controlled disturbances can be used as an effective way of the conservation of Molinietum caeruleae patches dominated by small meadow species being outcompeted by large-tussock grasses and over-shaded by willows.
8

The impact of neighbourhood and gap character on seedling recruitment of Trollius europaeus L. and Iris sibirica L. in Molinietum caeruleae meadows

67%
Kostrakiewicz-Gieralt K.
Biodiversity: Research and Conservation
|
2012
|
tom 28
9

Comprehensive syntaxonomy of Molinion meadows in southwestern Poland

51%
Kacki Z.
Acta Botanica Silesiaca. Monographiae
|
2007
|
tom 02
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