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1

Semi-natural grasslands: the effects of cutting frequency on long-term changes of floristic composition

100%
Kramberger B., Kaligaric M.
Polish Journal of Ecology
|
2008
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tom 56
|
nr 1
The objective of the experiment was to study the effects of different frequencies of cutting on long-term changes in the floristic composition of grassland, with an emphasis on the effects of very late cutting. Cutting at 2, 4, 6, 8 10 and 12-weekly intervals was applied from 1995 to 2006 in a randomized block experiment on semi-natural grassland fertilized with 170 kg N, 40 kg P and 150 kg K ha–1. The floristic composition of treatments was determined in May 1995, 1999, 2002 and 2006. In the final year (2006) the proportion of grasses in the dry matter of harvest was highest (77%) in the treatment with the least frequent cuts, and it was the highest obtained during the whole experiment. Under very frequent cuts, the proportion of grasses ranged only from 45 to 57%. Among legumes, only Trifolium repens L. was represented in high proportions in the dry matter of the harvest (from 19 to 25%) in 2006, but only in the treatments involving high cutting frequencies. The proportion of non-legume forbs in treatments involving low cutting frequency did not exceed other treatments; moreover, their proportion in the dry matter of the harvest in the treatment with the lowest cutting frequency decreased significantly to the lowest value (19%). The increased proportion of grasses in treatments with low cutting frequency indicates that a very late cut does not necessarily mean that forbs increase in the floristic composition, but can help grasses to retain their dominant and stable proportion in the semi-natural sward. Consequently, when farmers are being provided with financial incentives with the aim of protecting diversity and the natural environment, it is worth recommending also a very late cutting, which includes natural reseeding to a greater extent. This can help to find a compromise between farmers’ expectations of stable yield and quality forage, and the public interest in having grasslands of high biodiversity.
2

Larval habitat preferences of vanishing butterfly Hipparchia semele L.: surviving on human-altered habitats in the Czech Republic, Central Europe

72%
Kadlec T., Jakubikova L., Herman P.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 1
The Grayling Hipparchia semele L. belongs to rapidly vanishing butterfly species in its central and western European range. We studied larval microhabitat preferences of two last viable populations of the Grayling in the Czech Republic. The field study was carried out at two types of human-influenced habitats: a fly ash deposit — a postindustrial site partly left under natural succession processes, and a semi-natural extensively grazed xeric calcareous grassland in May and June 2012 and 2013. During five nights, 89 caterpillars were found (fly ash deposit: 8, xeric grassland: 81). The caterpillars were found on steeper slopes covered with sparse shrubs and shorter herbaceous vegetation with high amount of bare soil or rocks. The most frequently observed behaviour was feeding on fine-leaf fescue grasses with varied size of tufts and rather smaller height up to 20 cm. Usage of larval preferences in a way of active conservation management application is discussed.
3

The impact of extensive sheep grazing on the population and individual traits of Trollius altissimus Crantz

72%
Kostrakiewicz-Gieralt K., Kozak M., Kozlowska-Kozak K.
Polish Journal of Ecology
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2015
|
tom 63
|
nr 4
The montane glades in the Polish Carpathians were created centuries ago and have lasted mainly as a result of mowing and grazing. The observed abandonment of traditional methods of tillage in the last century led to adverse changes in vegetation cover, including a decrease in floristic diversity and the disappearance of many plant species and associations. One of a rare mountain taxa in Poland is the alpine globeflower Trollius altissimus Crantz. The investigations were carried out between June and September 2014 in the Hala Długa glade (Gorce Mts.) at two 36 m² plots: extensively grazed (P1) and unmanaged (P2). Light intensity, abundance and density of individuals and ramet clusters were significantly greater in the extensively grazed plot, whereas height of plant canopy, length of basal leaf petioles, width of leaf lamina, number and length of generative stems, number of flowers and follicles achieved higher values in the unmanaged plot. The structure of developmental stages and number of basal leaves did not differ remarkably between the studied sites. Also, the soil properties in both plots were very similar. The studies show that extensive sheep grazing has a positive influence on Trollius altissimus. In the studied locality such management contributes to the gradual spreading of this species. However, too intensive pasturage might eliminate this species as it has never been observed in any of the permanently grazed patches in the vicinity.
4

Restoration of subalpine species-rich grasslands: short-term vs long-term changes in the density and diversity of above-ground insects

72%
Karg J., Kujawa K., Manhart C., Marschalek H., Neugebauer K. R., Sachteleben J.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 1
Due to decrease in the area of extensively managed, semi-natural grasslands, that contribute to high biodiversity level preservation, the conversion of highly productive meadows to extensively managed, species-rich grasslands is now regarded as an important task for nature conservation. The aim of this long-term study was to assess the significance of restoration measures for diversity and trophic structure of above-ground insect community. That study challenges some weaknesses of previous studies as it was conducted with the use of suction trap enabling quantitative analyses of the changes in most insect taxa, and in a long time-span (1992–2005) in a set of permanent plots. The study area was located in a subalpine zone in Bavaria, near Laufen (Germany). The restoration process was initiated in 1996 by a cessation of fertilization and reduction of number of mowing to 1–2 per year. The changes in insect density and diversity (number of families) were monitored in ten restored and two reference plots with the aid of a suction trap. The changes in the insect community recorded during 14 years support findings from other studies that response of insect community to restoration process is usually slow on average. The short-term comparison in 2004–2005 between the restored and reference plots show that the first ones were characterized by more diverse (in term of family number) insect communities (as a whole as well as in guilds of predatory and parasitic species). From the other side, the long-term trend analysis shows that since 1998–2000 insect diversity and abundance was declining. Also trophic structure is fluctuating without clearly defined trend. These findings are in line with the results of the analyses of taxonomic composition similarity. They did not support the expectations neither that difference between initial and current taxonomical composition in a restored plot increases in time (mainly because of incoming new species), nor that spatial heterogeneity of insect assemblages should increase. However, spatio-temporal insect interactions between sample plots (located close to each other), linked to high movement ability of many insect taxa, could mask the changes in insect community caused by restoration.
5

Effects of soil disturbance and disease on the growth and reproduction of Lolium perenne [Poaceae] introduced to semi-natural grassland

58%
Erneberg M., Strandberg B., Strandberg M., Jensen B. D., Weiner J.
Polish Journal of Ecology
|
2008
|
tom 56
|
nr 4
593-604
We performed manipulative field experiments to investigate the effects of soil disturbance and exposure to a fungal plant pathogen, Puccinia coronata (Corda), on the establishment and spread of two introduced, cultivated genotypes of perennial ryegrass, Lolium perenne (L.). The two cultivars of L. perenne with different levels of susceptibility to P. coronata were introduced to grassland sites to investigate whether a plant cultivar selected to resist a pathogen shows better establishment in semi-natural plant communities than a susceptible cultivar. At two sites where L. perenne was already present, the addition of L. perenne seeds had no significant effect on the shoot biomass of the species, indicating that these populations were not seed limited. Exposure to the pathogen resulted in disease, and infected L. perenne populations showed increased shoot biomass over the course of the 3 year experiment and at harvest the final year, but no effect on seed production. Reproductive allocation was not affected by disease exposure in disturbed plots, but decreased in the presence of disease in undisturbed plots. The increased biomass observed in the semi-natural plant communities when exposed to the pathogen contrasts with the reduced biomass observed in garden experiments when the two cultivars of L. perenne were exposed to pathogen attack. The surprising positive effect of P. coronata on biomass in semi-natural communities indicates that processes here are more complex than in more intensively managed production systems.
6

Wintering farmland bird assemblages in West Hungary

58%
Baldi A., Somay L., Kovacs-Hostyanszki A.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 4
Farmland bird populations declining rapidly all over Europe. Most of the knowledge is, however, from the breeding season, and much less is known about the winter period, especially from Central and Eastern Europe. We censused wintering farmland bird assemblages in West Hungary, in 2011/2012. The censuses covered semi-natural and seeded grasslands, plough fields and wheat fields. The available winter seed food was estimated for each field from the top soil and from the vegetation. We recorded 25 species with 844 individuals on the fields. Semi-natural grasslands were the most important habitats for species richness of all, granivorous, and resident species, with seeded grasslands as the second best habitat. Abundance showed similar pattern, although with no significant effect for granivorous species and for short-range migrants. Seed mass was significantly different among the habitat types, higher on seeded grasslands and seminatural grasslands than on ploughed sites and winter wheat fields. Date had a significant effect on species richness and abundance with highest values in December. There was a positive significant correlation between bird species richness and seed mass only in December. Our results strengthen former findings that changes and drivers of wintering farmland bird populations may differ between Central and West Europe, and highlight the need for further, large scale studies to provide evidence base to guide agrienvironmental programs.
7
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Correlation between selected factors and quality of seminatural Western Carpathian grasslands

58%
Nowak J.
Annales Universitatis Mariae Curie-Skłodowska. Sectio E. Agricultura
|
2006
|
tom 61
8

Demography of a common butterfly on humid grasslands: Argynnis aglaja [Lepidoptera: Nymphalidae] studied by mark-recapture

58%
Zimmermann K., Konvicka M., Fric Z., Cihakova V.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 4
715-727
Much of the research into the demography of butterflies conducted in Europe during the last few decades focused on rapidly declining or, on the other hand, expanding species, whereas species with stable trend tend to be neglected by researchers. Argynnis aglaja, a widely distributed inhabitant of semi-natural grasslands, represents a suitable model for studying patterns of landscape persistence of not-yet-threatened grassland insects. Using mark-recapture method conducted for one season on humid meadows in Western Bohemia, Czech Republic, we show that this large-bodied species is capable to form large and dense populations, reaching densities of over 250 individuals per hectare. The adults were relatively long-living, an average female longevity (11.8 d) was over twice as high as an average male longevity (4.6 d), with maxima being 22 (a male) and 30 (a female) days. The prolonged female lifespan is beneficial for a species that do not emerge with fully-matured eggs and oviposits singly over large areas. Modelling mobility, well-approximated by an inverse-power function, predicted that about one individual in a thousand would cross the distance of 1000 meters. We conclude that the satisfactory conservation status of A. aglaja stems from its capability to reach high local densities combined with a good dispersal power.
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