| Abstrakt: |
The paper summarizes current information about suitable site conditions and regeneration ecology of pioneer tree species – birches (Betula pendula, Betula pubescens), alders (Alnus glutinosa, Alnus incana), rowan (Sorbus aucuparia), and aspen (Populus tremula) on calamity clearcuttings. Potential of species natural regeneration depends on amount of seed, methods and distance of their dispersal. Common distance of seed dispersal by wind is below 50 m for alders and 100 m for birches, seeds of aspen can be spread for longer distance. Absence of reserves in seeds emphasizes the importance of favourable conditions during seed germination and initial growth. Birch and aspen regenerate best on mineral soils, alders and rowan prefer humus conditions. The knowledge about regeneration ecology of pioneer tree species is fundamentally important to establish strategies for their regeneration on clearcuttings. [ABSTRACT FROM AUTHOR] |
