In European beech forests windstorms often create canopy gaps and change the level of incident light, soil moisture and nutrient availability on the forest floor. Understanding the interrelations between gap size and environmental change, and the effects these have on regeneration processes is a prerequisite for developing techniques of nature-based forestry. The aims of this study were to investigate the effects of gap size on the resulting spatial distributions of key abiotic environmental variables (light and soil moisture) in gaps, and to study how light and soil moisture affect the abundance and distribution of herb layer species. To do this we used eight artificially created gaps -three large (diameter: 35 -40 m) and five small (diameter: 10 -15 m) -in a mesotrophic submontane beech forest. Data on species' importance and substrate types were collected in systematically distributed 1 mÂ1 m quadrats before gap creation and on four occasions during the next two growing seasons. Hemispherical photographs were taken and analysed to estimate relative light intensity. Soil moisture was measured by frequency domain and capacitance probes. It was found that gap size had a profound effect on the environmental variables measured. While relative light intensity values in small gaps did not reach those in large gaps, soil moisture levels did reach similar maximum values in gap centres regardless of gap size. Richness, composition and total cover of herbaceous vegetation were different in small versus large gaps. Much of this difference was attributed to the presence of specific relative light intensities and also to the increased amount of available soil moisture in gaps. Species were differently affected by the combined effects of light and soil moisture, as well as by differences in available substrates. All this resulted in species-specific distribution patterns within gaps.

Water retention characteristics, rainfall, throughfall and soil water content dynamics were investigated in a low mountain area to compare a forest and a grassland. The soil water retention curve of the topsoil has similar shape in both studied areas, however that of the deeper soil layer shows more difference. We determined the precipitation depth, duration and intensity values of rainfall events. The relationship between rainfall and throughfall depth was described in linear regressions. Interception was calculated as the difference between rainfall and throughfall plus stemflow, assuming stemflow to be 3% of rainfall. Soil water content dynamics show a similar trend in the two vegetation types but the drying is more intensive in the forest in the soil layers deeper than 20 cm during the growing-season.

Central to the EU thematic strategy for soil protection is that areas affected by soil degradation through erosion, soil organic matter decline, compaction, salinization and landslides should be identified in a clear and consistent way. However, the current methodologies to achieve this often differ and this can result in different perceptions of risks among EU Member States. The aims of this paper are to i) assess the current status of assessment methodologies in Europe (EU27) associated with erosion, soil organic matter decline, compaction, salinization and landslides, and ii) discuss the issues associated with harmonization of these methodologies throughout the EU27. The need for harmonization is assessed using the relative share of common elements between different methodologies. The results demonstrate that the need for harmonization in methodology is greatest for erosion and compaction and least for soil organic matter decline and landslides. However, many of 1 the methodologies which were investigated are still incomplete and there are significant differences in terms of (i) understanding the threats, ii) methods of data collection, iii) processing and interpretation, and iv) risk perception. We propose two options for the harmonized assessment of soil threats: i) a two-tiered approach based on data availability and spatial scale and ii) a combination of standardization and harmonization for each assessment methodology. Future assessments should focus on the advantages and disadvantages of these options as the current situation will result in endless discussions on differences and the merits of particular methodologies instead of taking appropriate measures to reduce or eliminate the actual threats.