Vegetation of beech forests in the Rychlebské Mountains,Czech Republic,re-inspected after 60 years with assessment of environmental changes

From 1941–;1944 nearly 30 phytosociological relevés were completed by F. K. Hartmann in the Rychlebské Mountains, a typical mountainous area in northeastern Czech Republic. Of the original plots still covered with adult grown beech (Fagus sylvatica) forest, 22 were resampled in 1998 and 1999. In order to describe the recent vegetation variability of the sites 57 relevés were recorded. Changes in vegetation were estimated using relative changes in species density and ordinations (PCA, RDA). Environmental changes were assessed using Ellenberg indicator values when no direct measurements were available. A decline in species diversity has been documented, particularly, many species occurring frequently in deciduous forests with nutrient and moisture well-supplied soils around neutral have decreased. In contrast, several light-demanding, acid- and soil desiccation-tolerant species have increased. Natural succession, quantified as forest age, contributed slightly to these changes. In Ellenberg indicator values, a decline in F (soil moisture), R (soil calcium) and N (ecosystem productivity), and an increase in L (understorey light) were shown. This is interpreted as the influence of modified forestry management and of airborne pollutants. Intensified logging caused the canopy to open and soil conditions to worsen. The latter is most likely also due to acid leaching of soil cations (Ca, K, Na). This caused a decline in soil productivity, thus the effect of nitrification could not be detected. The original relevés may have differed in size influencing the results. This revised version was published online in August 2006 with corrections to the Cover Date.     

A functional analysis of vegetation dynamics in abandoned and restored limestone grasslands

Question: How do various plant functional groups and types are related to regeneration of limestone grasslands and to temporal changes in cover of trees and shrubs? Which mechanisms are responsible for changes in differently treated grasslands? Location: Southern Poland, 50° 01'N, 19° 50'E. Methods: A 12‐year restoration experiment after the clearing of a 35‐yr‐old secondary pine wood developed on limestone grassland, and a parallel observation of succession in neighbouring abandoned grassland were carried out. Changes in cover of species with different functional traits and established strategies in relation to time and cover of shrub layer were analysed using multiple linear regression. Results: Over 12 years the composition and cover of species changed in the studied grasslands, but significant differences still occurred between the old grassland and the grassland restored in former wood gaps and that developed in former closed wood. Despite the very close proximity of the old grassland, the composition of restored grasslands was still much determined by initial conditions. In these grasslands, the cover of Festuco‐Brometea species was significantly lower than in the old grassland. In all sites, the cover of species with large leaves and with leaves distributed regularly along the stem, and the cover of CS strategists increased. With increasing shrub cover in restored grasslands, the cover of annuals and biennials, tall species, and R and CS strategists decreased. Conclusions: Limited availability of seeds seems the principal reason for the weak regeneration of xerothermic limestone grasslands. Trees and shrubs inhibit the developed of both early successional species and perennials occurring in established communities. They significantly hinder regeneration of grasslands and should be cut every five or six years.     

Diversity and ecological characteristics of vascular flora in Mediterranean temporary pools

Vascular flora of Mediterranean temporary pools has been studied with the aims to define its diversity and to individuate the ecological characteristics of the different plant groups associated with this relevant and endangered habitat type. Overall, 246 species were found of which 108 were terrestrial, 57 generalist of aquatic or wet habitats and 81 typical of temporary water and strongly linked to temporary pools. The results suggest that: (i) vascular flora associated with Sardinian Mediterranean temporary pools is rich and diversified; (ii) rare ferns are better represented than previously reported; (iii) plant species are generally heliophilous and acidophilous, specialized temporary pool species mainly differing from the unspecialized ones in relationship to their soil moisture requirements; (iv) these habitats are particularly important for maintaining regional freshwater biodiversity.     

Nature conservation on decommissioned military training areas – German approaches and experiences

Military training areas (MTAs) host high numbers of endangered habitats and species due to their large area, generally low fertilizer and biocide exposure, and a high dynamic of disturbances caused by military training activities. Since the end of the Cold War in the 1990s, thousands of former military properties have been closed due to international disarmament agreements. Based on a literature review, we present the importance of decommissioned MTAs in Germany for nature conservation, their number, area, and status, as well as the German approaches and experiences managing these sites. More than 119,000 ha of former military areas of high conservation value were transferred by the Federal Government to German Federal States, the German Federal Environmental Foundation, and other nature conservation organizations as part of the so-called National Nature Heritage (NNH), and an additional 60,000 ha were saved in other ways. It is a big challenge in nature conservation to establish appropriate management systems to maintain the endangered habitats and species on these sites, most of which are contaminated with unexploded ordnance (UXO). Several projects have been implemented in Germany to develop strategies to deal with UXO contamination. We discuss management options, from prescribed burning on UXO contaminated sites to the establishment of wilderness, in the light of the requirements of the European Union’s Natura 2000 network of protected areas.     

How does habitat diversity affect the species–area relationship?

Aim   To examine the way in which 'area' and 'habitat diversity' interact in shaping species richness and to find a simple and valid way to express this interaction.
Location   The Natura 2000 network of terrestrial protected areas in Greece, covering approximately 16% of the national territory.
Methods   We used the Natura 2000 framework, which provides a classification scheme for natural habitat types, to quantify habitat heterogeneity. We analysed data for the plant species composition in 16,143 quadrats in which 5044 species and subspecies of higher plants were recorded. We built a simple mathematical model that incorporates the effect of habitat diversity on the species–area relationship (SAR).
Results   Our analysis showed that habitat diversity was correlated with area. However, keeping habitat diversity constant, species richness was related to area; while keeping area constant, species richness was related to habitat diversity. Comparing the SAR of the 237 sites we found that the slope of the species–area curve was related to habitat diversity.
Main conclusions   Discussion of the causes of the SAR has often focused on the primacy of area per se versus habitat heterogeneity, even though the two mechanisms are not mutually exclusive and should be considered jointly. We find that increasing habitat diversity affects the SAR in different ways, but the dominant effect is to increase the slope of the SAR. While a full model fit typically includes a variety of terms involving both area and habitat richness, we find that the effect of habitat diversity can be reduced to a linear perturbation of the slope of the species accumulation curve.     

What is a suitable management for Typha latifolia control in wet meadows?

Aim

Typha latifolia causes serious problems in wet meadows by overgrowing and suppressing other native plants. To determine suitable management for T. latifolia control, we addressed the following question: What are the effects of long-term cutting at different frequencies (once or twice per year and no management) and biomass removal on cover and other characteristics of T. latifolia, and on sward productivity and plant species composition?

Location

Malá Strana nature reserve, Jizerské hory Mountains, Czechia.

Methods

A long-term experiment arranged in a randomised block design with three blocks was established in 2005. Data were collected from five treatments: unmanaged control; cutting once a year in June without biomass removal and with biomass removal; cutting twice per year in June and August without biomass removal and with biomass removal. Percentage cover of T. latifolia and other vascular plant species was visually estimated and T. latifolia characteristics (tiller density, height, dry-matter biomass [DMB] yield and litter), sward height and DMB yield were measured during 2005–2018 at the end of June.

Results and Discussion

Regular cutting once or twice per year regardless of cut biomass removal led to reductions in tiller density, height, litter and DMB yield of T. latifolia. Biomass removal had only a slight tendency to affect T. latifolia characteristics. The higher frequency of cutting significantly decreased the mean T. latifolia cover, litter and DMB yield. Cutting once or twice per year regardless of biomass removal led to successive changes in plant species composition but had no effect on the species richness and evenness.

Conclusions

Cutting at least once per year without biomass removal seems to be sufficient to achieve a decrease in DMB yield and litter of T. latifolia plants, and thereby maintain the wet-meadow vegetation without loss of species richness and also preventing the overgrowth of shrubs and trees.     

River corridor plants revisited: What drives their unique distribution patterns?

The phenomenon whereby some plant species display a river corridor distribution pattern has long been recognized but is still poorly understood. The goals of this study were to supplement the list of river corridor plants for Central Europe, analyse their habitats and compare their ecological features with those of their widely distributed counterparts. The ATPOL (Atlas of Poland) database was used to compile a list of river corridor plants of Poland and calculate their river corridor-specificity indices (RCSIs). The Ellenberg indicator values, dispersal modes and life forms of river corridor and widely distributed species were compared using generalized linear mixed models (GLMMs). Eighty-five species were classified as river corridor species. The most numerous habitat groups were meadow species (19%), wet-habitat therophytes (15%), riverside tall herbs (13%) and species of dry, sandy soils (12%). These species had mostly requirements for a higher temperature and alkalinity than widespread species. Among river corridor plants, there were a few eurytopic species. Corridor species had usually only one life form and less dispersal modes than widespread species. Hence, specific demands of corridor plants and lower phenotypic plasticity may explain their restricted geographical distribution. The definition of the river corridor plant species needs modification.     

Forest plant community changes in the Spačva lowland area (E Croatia)

The forests in the Spa?va Basin are a complex of lowland forests in the region of Slavonia (eastern Croatia). The present state of the forests is strongly influenced by intensive exploitation and hydro-ameliorative activities carried out in the past. The aim of this study was to consider the extent of changes in species composition, and the extent of environmental changes in forest communities of the Spa?va Basin in relation to research conducted between 1969 and 1971. The species composition of four communities (Carpino betuli-Quercetum roboris, Genisto elatae-Quercetum roboris aceretosum tatarici, and caricetosum remotae, and Leucojo-Fraxinetum angustifoliae) is studied by comparing 41 old and 57 new relevés. Changes were estimated using ordinations (RDA, CCA, DCA) and changes in species frequency and cover. A general trend of moisture reduction was noticeable among all communities. All vegetation types are becoming floristically more similar. An increase in frequency and cover of flood intolerant woody species (such as Carpinus betulus, Cornus sanguinea, Tilia tomentosa, and Acer tataricum) as well as a decrease of vernal species related to wet habitats are particularly evident. The succession of all studied communities is resulting in loss of the mosaic community pattern characteristic of lowland alluvial forests.