2014. július 31., csütörtök
Megjelent a Cambridge University Press gondozásában, Kathrin Kiehl, Anita Kirmer, Nancy Shaw és Sabine Tischew által szerkesztett Guidelines for Native Seed Production and Grassland Restoration c. tanulmánykötet. Ebben a kötetben jelent meg egy fejezetünk, melyben az Egyek-Pusztakócs térségében zajlott gyeprekonstrukció eredményeit mutatjuk be. A könyvfejezet a honlapomról szabadon letölthető, az absztrakt pedig az alábbiakban olvasható.
RECOVERY OF ALKALINE GRASSLANDS USING NATIVE SEED MIXTURES IN THE HORTOBÁGY NATIONAL PARK (HUNGARY)
Alkali grasslands are included in the Natura 2000 Habitats Directive as Pannonic salt steppes and salt marshes (1530) priority habitats. They harbour a unique flora and fauna; thus, conservation and restoration of their biodiversity is of a high priority. Technical restoration is often necessary to mitigate the negative landscape-scale effects of agricultural crop production and to increase the area occupied by grasslands. Recovery of grassland vegetation can be facilitated by sowing seeds of target species. Low-diversity seed mixtures provide a cost-effective measure, as they are easily formulated and applied in large-scale grassland restorations. Between 2004 and 2008 a total of 760 ha of former croplands were sown with low diversity seed mixtures of appropriate species to restore basic alkali grasslands in Hortobágy National Park, East-Hungary. The seed mixture contained seeds of Festuca pseudovina and Poa angustifolia. After soil preparation seed mixtures were sown at a rate of 25 kg/ha in October. The sown fields were mown once a year. To follow vegetation changes, two 25 m2 sampling sites per field were established after sowing. To assess the effect of mowing on the vegetation, one sample site in each field was not mown after the third year. Biomass was sampled in the permanent plots to monitor vegetation changes. The rapidly developing perennial cover effectively suppressed short-lived weeds in the aboveground vegetation, but allowed the preservation of their soil seed banks. We found that the high levels of biomass production typical of alkali grassland restorations in former croplands are beneficial for the suppression of short-lived weedy forbs, but might hamper the immigration of characteristic alkali grassland species. We stress that a long-term postrestoration management program is essential for sustaining recovered grassland biodiversity. This could be accomplished by mowing in the first few years, and later by extensive grazing by cattle and sheep. The latter management practice also supports the establishment of characteristic alkali grassland species.
2014. július 11., péntek
Megjelent egy közép-európai szikes mocsarak és nádasok ökológiájáról és konzervációbiológiai helyzetéről szóló könyvfejezetünk a NOVA kiadó gondozásában. A könyvfejezet letölthető a honlapomról. A könyvfejezet összefoglalója az alábbiakban olvasható.
Alkali marshes of Central-Europe: Ecology, management and nature conservation
Alkali marshes and wetlands are among the few natural open ecosystems in Central Europe. Inland alkali marshes of the European steppe zone are typical only for the Pannonian biogeographical region. They are characterized by shallow water cover, high seasonal fluctuations in water availability and by considerable salt-content in water and soil. Even small changes in the above parameters can result in significant differences in habitat structure and species composition. Alkali marshes are usually characterised by a species-poor vegetation, characterised by a few bulrush species (Bolboschoenus maritimus, Schoenoplectus tabernaemontani and S. littoralis). As indicators of the alkali character of these wetlands several halophytes and salt-tolerant species are present in the vegetation, like Aster tripolium ssp. pannonicus, Atriplex littoralis, Chenopodium chenopodioides and Plantago maritima. In sites with moderate salinity Phragmites australis, Schoenoplectus lacustris and Typha spp. can reach high cover scores. Several Pannonian endemic species are also present in alkali wetlands, like Cirsium brachycephalum, Acorellus pannonicus and Puccinellia limosa.
Due to the uneven pattern of the soil salt-content and dynamic changes in water regime different types of alkali marshes compose a diverse mosaic pattern even in the small scale. This natural mosaic structure contributes to the maintenance of landscape-scale biodiversity, and also provides favourable habitats for several animal taxa, especially for breeding and migrating birds. These wetlands are also important as green corridors and stepping stones in fragmented agricultural landscapes. Alkali marshes are especially important in European nature conservation; they are included in the Natura 2000 system as priority habitats "Pannonic salt steppes and marshes". Reintroduction of traditional land use, like cattle grazing is essential to maintain the structure and species diversity of these alkali habitats. Alkali marshes are threatened by land-use changes, amelioration, eutrophication and fragmentation. Improper management, as regular reed harvesting also decreases the spatial diversity of these habitats.