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This research dealt to two grasslands potentially developing the same vegetation type because sited in the same environmental contest (bioclimate, substratum, soil, slope, altitude) but under diverse management regimes (grazing and mowing) for many decades. The evidenced differentiation between the two pastoral vegetations can be attributed to disturbance type and the statistical functional analysis performed through seven plant traits (prostrate form, early flowering, storage organs, clonal ability, basal meristems, chemical defences and hairs), revealed the distinguishing patterns. Discriminant analysis pointed out typical biological attributes for each disturbance conditions, while from correlation analysis emerged different possible traits combinations which do not follow the previous traits separation. Such outcomes are explainable because both grazing and mowing provoke aboveground phytomass removal, although grazing is a selective pressure, while mowing gives to all the species the same development chances. It is reasonable to conclude that convergent strategies within the two systems are possible and frequent.
European semi-natural calcareous grasslands are species-rich ecosystems, considered as priority habitats by the European Union (92/43/EEC Directive) and judged worthy of conservation. They are in strong decline in extension and are threatened by abandonment throughout Europe. It is known that grasslands management (grazing, mowing) acts as driving force in plant community diversity, which in turn is an important conservation aim of European environmental policies. The area of current pastoral landscape (about 1000 ha) of the North Adriatic (Cicarija, Croatia) was studied in order: 1/ to understand which factors drive floristic differentiation . environmental features and/or grassland management conditions, 2/ to identify indicator species sets linked to those factors and 3/ to appraise the effects of management type on the coenological and functional composition of indicator species. 73 phytosociological releves were carried out; for each of them field data (altitude, aspect, slope and land form), productivity measurements and information on grassland management were collected. Redundancy analysis (RDA) identified a productivity-related soil moisture gradient as the environmental driving force of grassland floristic differentiation. Indicator species analysis (ISA) detected the indicator species sets related to environmental features and management type. The results indicate that undergrazing and the lack of periodic mowing are responsible for the higher total variance of floristic data set explained by environmental parameters rather than by management (use/not use). For the same reasons, the variations that emerged from comparison of the functional characteristics of the indicator species of grazing and of mowing (avoidance strategy, life form, and storage organs) proved more important than those observed in comparing used and abandoned grasslands. The management system adopted (grazing or mowing) appears in turn to be conditioned by the soil moisture/productivity gradient.
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