Regeneration potential of the Hungarian (semi-)natural habitats I. Concepts and basic data of the MÉTA database

Abstract

Regeneration potential is regarded as a kind of functional indicator, which is applied for the assessment of the habitat quality and a kind of nature conservation value. In this context "quality" does not refer to the actual state but possibilities for the future. During the MÉTA project, regeneration potential have been recorded on the scale of the quadrates (35 km2, 2,813 quadrates in Hungary), for each habitat of the quadrate (ignoring some featureless habitats). We have estimated three different kinds of regeneration potential: on spot, on the place of neighbours and on old-fields open water, bare rock. The categories used were: good regeneration ability, moderate, low, or there is no place for regeneration. Values of regeneration potential on spot are usually rather high. Habitats with the highest regeneration potential are the aquatic ones, shrub vegetation, halophytic vegetation, marshes, grasslands with woodland origin, sand poplar-juniper woodlands, and the poorest is the regeneration potential of the forest steppe woodlands. Lower are the values of the regeneration potential of each vegetation type on the place of the neighbours. Relatively easily spread onto the neighbouring vegetation patches the halophytic habitats, poplar-juniper woodlands, the secondary shrub vegetation, some aquatic habitats, certain riverine vegetation types and marshes. Moderate or lower is this value of this regeneration potential category for the xeric highland woodlands, rocky habitats, xeric and mesic lowland woodlands, grasslands with woodland origin and some fen vegetation types. In spite of the rather low values calculated for the whole country, the following habitats regenerate relatively well on old-fields, open water or rock surfaces, or in abandoned vineyards: the dry secondary shrub vegetation, poplar-juniper woodlands, Scots pine woodlands, halophytic habitats, some aquatic habitats and marshes. Most habitats regenerate poorly, for example, the zonal woodlands. Never or barely regenerate on old-fields: some fen habitats, the steppe oak woodlands, mesic lowland woodlands, some rock habitats, acidophilous woodlands, the zonal woodlands, the rock and sand coniferous woodlands. When comparing the values of regeneration potential on spot, on the place of the neighbours and on old-fields, most striking is the fact that the least habitats have moderate or high regeneration ability in case of the third kind of regeneration potential, and regeneration ability on adjacent vegetation patch represent a transitional state from this aspect. Some of the edaphic habitats are quite mobile (e.g. halophytic, marsh or certain fen habitats), while others migrate only rarely (rock or other fen vegetation types). Some habitats though regenerate admirably on spot, yet never invade new areas; for instance, rock vegetation, acidophilous woodlands, grasslands with woodland origin. Others has almost the same regeneration potential values on spot as on the place of the neighbours, e.g. some steppe woodlands and shrub habitats on their own clearings, or some habitats of secondary origin. Certain rock habitats, some fen and riverine vegetation types and some of the close woodlands regenerate well on spot, but almost never on old-fields. There are some habitats, which has high regeneration potential on the place of the neighbours, but has low values for the old-fields. Most of them are closed woodlands, shrub and certain fen habitats. According to our expectations, the experience gained during the MÉTA mapping will give an impulse to the study on regeneration potential. © 2008 Akadémiai Kiadó.