Changes in diversity of protected scree and herb-rich beech forest ecosystems over 55 years

Species composition along with spatial and age structure are the main attributes of forest ecosystems. The diversity of scree forests and herb-rich beech forests was analyzed in the Broumovsko Protected Landscape Area, the Czech Republic. The paper objective was to evaluate forest structure and dynamics of species diversity of tree layer, natural regeneration and herb layer in the period 1961-2016. Scree forests were structurally, and species very rich forest stands, in herb-rich beech forests the stands were of medium richness. Studied stands managed by small-scale methods, in the past especially by coppicing and later by shelterwood and selection felling, have maintained high species biodiversity during the 55 years of observation. Substantially higher biodiversity was found out in scree forests compared to herb-rich beech forests. Based on the comparison of predominantly coppiced forest stand and stand of generative origin at sites of scree forests, coppice have maintained higher biodiversity than high forests. Species richness increased during the observation period, but species evenness had mostly decreasing tendency. Species heterogeneity in coppiced scree forests increased in tree layer and natural regeneration, but it decreased in herb layer; inverse dynamics was observed in the high forests. Changes in biodiversity dynamics were remarkable for coppice, while high forests showed relatively high level of stability. During study period herb population of light-demanding species and species characteristic for broadleaved forests decreased, while an increase in shade tolerant, moisture-demanding and nutrient-demanding species, especially nitrophilous species was confirmed. Moreover, occurrence of thermophilic plants increased, respectively cold-tolerant plant population decreased in relation to climate change.