Drivers of plant diversity in grassland metacommunities
This thesis investigates how dispersal processes and local environmental conditions interact to drive patterns of plant diversity in fragmented grasslands with variable site conditions. Main findings are (i) that high soil nutrient concentrations reduce the effectiveness of dispersal, (ii) that current diversity patterns reflect past rather than present dispersal processes and (iii) that high immigration rates from primary grasslands during early successional stages are the principal driver of successional trajectories in secondary grasslands. Conservation managers should actively assist dispersal and simultaneously reduce high soil nutrient concentrations.
This article is a study of competitiveness of agricultural enterprises of different legal forms using the author's own assessment procedure based on matrix-rating method with integral index. Ranging of agricultural enterprises according to their level of competitiveness has been done, preferred forms of economic activity in current conditions and trends of increasing their competitive positions have been defined. Author makes a conclusions about different influence of the studied factors on competitiveness of agricultural enterprises of different legal forms. The greatest influence is done by the provision of resources of enterprises, because it affects the quality and quantity of output.