Vegetation structure will include the following components for the purpose of this lecture:-Texture, the distribution of above-ground biomass, the distribution of sizes (diameter, height) of individuals (shoots) -Stratification, the formation of layers, the vertical distribution of biomass -Pattern, the occurrence of regular, clumped, or random distributions of plant units of different species -Interaction pattern, the occurrence of joint distributions of plant units of different species through positive interactions, or of species exclusions.Dynamics will include: Disturbance, the occurrence of abiotic and biotic events which lead to the disappearance of plant units and the subsequent formation of gaps.Fluctuation, the change in the quantity of strength of one or more environmental factors leading to the disappearance, appearance, and change in quantity of individual plant species.Succession, long-term dynamics leading to directional changes in the composition of plant communities, including their structure.Diversity will include the following components: Species richness, i.e. the number of species on a representative area occupied by a certain plant 'community, or the rate of increase in species number with increasing area (alpha-diversity).Size of basic area, i.e. where one and not more than one species occurs (determines together with alpha the number of species on the representative area).Dominance-diversity relation, i.e. the relative importances of species biomass or cover values.Relations between structure and dynamics include:-Creation of gaps, %ntipatterns'l, through disturbance and the subsequent re-establishment of species, mainly through germination, adapted to the different light and moisture conditions. Grazing and mowing will be considered as special forms of disturbance which usually have a regu1A.r occurrence and do not lead GIORNALE