The growth, structure and production of mixed beech (Fagus sylvatica L.) forests were analysed  in the Broumovsko Protected Landscape Area, Czech Republic. The objective of the paper was to evaluate stand structure, timber production and dynamics of forests with historically different silvicultural practices in relation to climate conditions, management and game damage. The results indicate that scree forests (coppices and coppices with standards) were stands with high-rich species diversity and structure compared to herb-rich beech forests (high forests) with higher timber production. The Norway spruce (Picea abies [L.] Karst.) was the most sensitive tree species compared to low growth variability in European beech. The climate factors had the highest effect on radial growth from June to August. Natural regeneration showed great density potential (13,880–186,462 recruits·ha^–1), especially in expansion of maples and European ash (Fraxinus excelsior L.). However, recruits were seriously limiting by damage caused by hoofed game, especially in silver fir (Abies alba Mill.; 53% browsing damage), wych elm (Ulmus glabra Hudson; 51%) and rowan (Sorbus aucuparia L.; 50%).

The goal of this work was to determine the best method of breaking the achene dormancy in Potamogeton praelongus Wulfen. The ways of breaking achene dormancy studied in this experiment included methods of achene storage, stratification, UVA radiation, anaerobic conditions, mechanical disruption of achenes?outer layers and their chemical disruption by NaClO. Nine different treatments of achenes were combined with two methods of achene storage. Particular achene treatments and storage conditions were proven to have a significant impact on breaking dormancy. Although the highest germination rate (83.3%) was achieved when the dormancy was broken chemically by long effect of 100% concentrations of Savo detergent (containing 5% NaClO), the growth of the sprouts was subsequently inhibited due to toxic effects of Savo. Thus the most successful treatment was based on changing temperature, e.g. 2.5 months of cold storage followed by 14 days at room temperature (germination rate 32.7%). This treatment was also most similar to the natural process. Germinated achenes were also found in Petri dishes exposed to UVA radiation, anaerobic conditions and chemical disruption of the outer layers. Results of these treatments were influenced by the storage method.

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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.