Authors:K. Virágh, A. Horváth, S. Bartha, and I. Somodi
Conservation treatments often take place at the scale of vegetation stands and affect within-stand heterogeneity and coexistence patterns of species first. Therefore, it is important to capture changes in these characteristics of vegetation to assess response to treatments early. We propose a method based on Juhász-Nagy’s information theory models, which is capable of describing fine-scale spatial structure of plant communities and characterizes temporal processes as a function of spatial pattern. The proposed multiscale approach handles structural complexity and its dependence on spatial scales with the help of a few coenological descriptors and helps to reveal how fine-scale vegetation pattern affects dynamics. The information statistical functions used in our study (species combination diversity,
) characterize the scale-dependent variability of multispecies coexistence (structural complexity) and multispecies spatial dependence (the degree of spatial organization). The maxima of these functions and the related characteristic areas (plot sizes) can be used to construct an abstract coenostate space, where spatiotemporal processes (degradation, regeneration) can be followed. We demonstrate the usefulness of the proposed methods for detecting degradation and monitoring vegetation changes in different stands (18 seminatural and 13 slightly degraded stands) of
dominated wooded steppe meadows in Hungary. The information theory measures captured changes of fine-scale vegetation patterns that remained unexplored by species richness and Shannon diversity. The maximum values of information statistical measures and the related characteristic areas detected differences between seminatural and slightly degraded stands. In the coenostate space, seminatural stands appeared to be less variable compared to degraded ones. Seminatural stands from various geographic locations were less dispersed in this space, i.e., less heterogeneous than degraded ones. The two regions of the coenostate-space defined by the set of seminatural and degraded stands were significantly different. Furthermore, we conclude that the region containing seminatural stands can be regarded as a reference region in this abstract space. Temporal variation of seminatural and degraded stands was also clearly different. Therefore, we recommend the approach for exploring the actual dynamic states of vegetation stands to be treated and for following consequences of treatments in order to determine effectiveness of the conservation action.
Alpine grasslands harbour species-rich communities of plants and invertebrates. We examined how environmental variables and anthropogenic impact shape species richness and community structure of terrestrial gastropods in alpine grasslands in the Val Müstair (Eastern Alps, Switzerland). Gastropods were sampled using a standardised method at 76 sites spanning an elevation range from 1430 m to 2770 m. A total of 4763 specimens representing 52 species were recorded. Correspondence analysis based on presence/absence data revealed that the grassland gastropod community was structured in a complex way with elevation, wetness, grazing intensity and inclination of the sites as key factors, while abundance-based analysis identified the importance of the elevation and wetness of sites. Generalized linear model showed that species richness decreased with increasing elevation and increased with increasing soil pH. The grassland gastropod communities were characterized by a high beta diversity, as indicated by the SDR-simplex analysis. Species-specific traits of gastropods showed sensitivity to the environmental characters of the sites, as shown by a fourth-corner analysis.
Authors:Z. Dajic-Stevanovic, I. Pecinar, M. Kresovic, S. Vrbnicanin, and Lj. Tomovic
Salt affected soils especially in the arid and semi-arid regions of the world exhibit a significant increasing tendency. The relationship between plant/vegetation richness and soil salinity was assessed for 21 grassland asscociations and one subassociation of Serbia. Among studied grasslands, the ass.
Halo-Crypsidetum aculeatae, Suaedetum maritimae
were found to be indicators of the extremely saline soils (solonchak), whereas the ass.
Lepidio crassifolio-Festucetum pseudovinae
were typical indicators of sodic soils (solonetz). Management and use of grasslands of salt affected soils and evaluation of pastoral value and salinity tolerance of the studied grasslands was performed.
Authors:E. Magyar, K. Buchgraber, D. Warner, and L. Szemán
(Influence of fertilisation and grassland management on the development of herbs on permanent grassland.) — This investigation was carried out (HBLFA Raumberg-Gumpenstein) with differently kind of fertilisation and cutting regimes on permanent meadows. This paper focuses on influence of grassland management on plant composition with special regard to herbs. Extensive management leads to an increase in herbs. The main reason is an open sward, leading to many gaps. Fodder quality is medium in these species-poor stands. Intensive management practices leads to an increases in the proportion of grasses and several herbs which are adapted to increased management intensity. Fodder quality increases, except of a high degree of coverage by
. Highest plant species richness is related to moderately management practice. Species richness will decreases both extensive and intensive management in a long-term.
Authors:L. Halada, H. Ružičková, S. David, and A. Halabuk
Significant transformation of agriculture took place in Central Europe during the second half of the 20
century. The paper reviews the nature and consequences of this process in terms of grassland management and land use changes in the Liptov region (N Slovakia) and their impacts on plant communities of fen meadows (
Caricion davallianae, Caricion fuscae
), wet meadows (
) and mesophilous grasslands (
). We studied in detail the changes in structure of the rare plant community
(Kühn 1937) Oberd. 1957 that occurred between the first period (1974–1983) and the second period (2002–2003). We recorded the decrease in abundance of species characteristic for permanently wet and fen meadows (alliances
and the increase in abundance of characteristic species of seasonally dried, mesophilous and thermophilous meadows and mesophilous fringes (classes
Molinion caeruleae, Bromion erecti
). In the second studied period, a large group of mesophilous and thermophilous species appeared as new in this wet-meadow community. A cumulative impact of different factors, especially drainage and intensification of surrounding grasslands as well as abandonment of the community can represent reasons responsible for observed changes. Regardless identified changes, the community still maintains its typical character in significant proportion of the studied sites and hosts a high number of threatened plant species.
Botanical changes were examined on a ten-year-old semi-natural grassland established using mixtures with high species diversity. The mixtures contained seventeen wild flowers of natural origin together with two leguminous and seven grass species or varieties. Three different mixtures were arranged in three replications. The grassland management system was non-intensive (without nutrient supply or irrigation). A survey involving cover assessment revealed nine residual species from among the twenty-six originally sown. The main question addressed in the study was whether there was any connection between the ecological properties of the habitat and the ecological needs of the residual species and it was concluded that all the residual species had similar temperature, water balance and soil requirements. It could be seen that the present plant association gave a good reflection of the results of soil analysis. This suggests that soil analysis should be carried out before sowing new species-rich grasslands in order to compile a mixture suited to the nature of the habitat.
The botanical composition of grasslands determines the agronomic and natural values of swards. Good grassland management usually improves herbage value, but on the other hand it frequently decreases the plant diversity and species richness in the swards. In 1999 a field trial in a split-plot design with four replicates was therefore established on the
type of vegetation in Ljubljana marsh meadows in order to investigate this relationship. Cutting regimes (2 cuts — with normal and delayed first cut, 3 cuts and 4 cuts per year) were allocated to the main plots and fertiliser treatments (zero fertiliser — control, PK and NPK with 2 or 3 N rates) were allocated to the sub-plots. The results at the 1
cutting in the 5
trial year were as follows: Fertilising either with PK or NPK had no significant negative effect on plant diversity in any of the cutting regimes. In most treatments the plant number even increased slightly compared to the control. On average, 20 species were listed on both unfertilised and fertilised swards. At this low to moderate level of exploitation intensity, the increased number of cuts had no significant negative effect on plant diversity either (19 species at 2 cuts vs. 20 species at 3 or 4 cuts). PK fertilisation increased the proportion of legumes in the herbage in the case of 2 or 3 cuts. The proportion of grasses in the herbage increased in all the fertilisation treatments with an increased numbers of cuts. Fertiliser treatment considerably reduced the proportion of marsh horsetail (
) in the herbage of the meadows. This effect was even more pronounced at higher cut numbers. The proportion of
in the herbage was the highest in the unfertilised sward with 2 cuts (26.4 %) and the lowest in the NPK-fertilised sward with 4 cuts (1.4%).