Ábrahám Levente (szerk.): Válogatott tanulmányok IX. - Natura Somogyiensis 24. (Kaposvár, 2014)
Miókovics E. - Bódis J. - Molnár Zs.: Analysis of landscape change in the Nagyberek (Somogy, Hungary) with the DPSIR Framework
Miókovics E., Bódis J., Molnár, Zs.: Analysis of landscape change 11 serves the interest of nature conservation (25. §) and only extensive and environmentally friendly agricultural practices may be used. The Hungarian Ecological Network prohibits to designate the natural areas as built-up area. The above mentioned laws (responses) are valid in the case of other categories as well. II. grasslands: meadows and pastures, mesotrophic meadows, rich fens In the case of wet grasslands and marshes the main driving forces are the same. Thus the conversion and overseeding of grasslands appear as pressures in the period of intensive agriculture. Further driving forces are: change of lifestyle, disappearance of rural lifestyle, development of mechanisation, economic transformation. Pressures are: disappearance of the pastoral grazing system and the small-scale livestock farming, reduction of mowing and grazing. As a consequence of unsettled ownership the secondary succession of former arable land and grasslands has begun. Grazing using electric or fixed fences can not suit to the natural cycles of grasslands and can not manage properly the different vegetation patches. Large mesotrophic meadows can be found in the “Pogány- völgyi rétek” Natura 2000 area (HUDD20035) and near Somogyszentpál. Adventive and invasive species, such as Amorpha fruticosa, Fraxinus pennsylvanica, Acer negundo, Solidago spp. are frequent in the area. These species spread as a consequence of the abandonment of arable fields and decrease the diversity and forage value of grasslands. This degradation affects 30-40% of the grasslands. Conservation legislation gives the responses. It specifies the followings: e.g. mowing or grazing is mandatory on Natura 2000 sites, invasive species should be suppressed, licence is needed to winter grazing, overgrazing of wet grasslands is prohibited. The system of agri-environmental supports incites extensive agriculture with higher payments. III. forests: plantations and natural forests Driving forces began with large-scale farming: shelter forest belts were established between the parcels, Populus x euramericana plantations were established for variety trials. The sand banks and sand hills were forested with Pin us sylvestris and Robinia pseudoacacia. Those areas were forested which were unsuitable for agricultural utilization. In recent years Fraxinus pennsylvanica, Amorpha fruticosa Acer negundo have been planted in large areas for game management purposes. These plantations mean pressures: the spontaneous spread of Acer negundo, Robinia pseudoacacia and Fraxinus pennsylvanica degrade the habitats in the Nagyberek. The ratio of natural and seminatural forests is negligible, the undergrowth is degraded. One important response is the clearcutting of the 30-40 year-old plantations. In accordance with regulations (Balaton Act, Natura 2000, Forest Act) these areas shall be replanted only with native species. Thus the species composition of forests is changing, however their extent must not decrease according to the Forest Act. IV. arable land From the 1950s large-scale collective farming has dominated for decades in the Nagyberek. Thousands of hectares were converted to intensive farming, where inter alia, cotton was produced as well. After the end of communism it became important to manage the land economically, therefore arable lands have started to serve game management purposes. Recently game management is the significant driving force because many abandoned fields are maintained for small game breeding. The spread of weed species from these fields is considered as an impact on the landscape. First the annual crop weeds appear on the abandoned fields, then Solidago spp. infest them in 2-3 years. Without management (mowing or grazing) this state keeps steady and the vegetation can
