Long-Term Changes in Plant Life Forms as a Consequence of Grazing Exclusion under Arid Climatic Conditions

摘要: El Ouara natural region (southern dry area of Tunisia) is characterized by harsh climatic conditions (high temperature, low rainfall). It the preferred destination many herds disturbing local ecosystems and loosing palatable plant species. These stresses human disturbances affect vegetation communities. Conservation management has been imposed in order to preserve national floristic heritage biodiversity. Among proposed techniques was creation Sidi Toui park since 1991. This study aims assess changes flora life forms strategies (Raunkiaer, Noy-Meir Grime types) inside outside from 1990 2011. The Raunkiaer biologic spectrum considered as a adaptation strategy conditions. classified plants on basis their photosynthetic activity during season (arido-passive arido-active species). C–S–R model gathered three groups (Competitive (C), Stress-tolerant (S) Ruderal (R)). quadrat point method used evaluate status. Main results are (i) Chameaphytes Hemicryptophytes cover increased at beginning decreased after long period protection, (ii) Therophytes dominate 20 years (iii) Arido-active species sensible disturbance protection effects (iv) S, CS CRS RS ones. Copyright © 2015 John Wiley & Sons, Ltd.