contribution to the study of quantitative and qualitative aspects of steppe formations for the characterization of desertification in semi-arid environment: saida, algeria.

in semiarid regions such as saida, the steppe ecosystem is currently submitted to desertification under the combined effect of human activity and climate change. our study is a contribution to the assessment of the biodiversity of steppe formations through a phytoecological diagnosis at the south zone of the wilaya of saida. to achieve the objective of this study, a methodological approach based on studies of multifarious types. thirty floristic and soil have been made to end better now characterize the floristic richness, biological type and soil type. the sampling technique is between purposive sampling and a statistical sampling to two degree (transect surveys). the period of fieldwork is the spring season of 2012. the results obtained clearly show that vegetation cover and soil are the subject of an alarming deterioration that results in a very advanced stage of desertification. this results in a drop in agricultural production and installation of non-palatable species by livestock.