Impact of ecosystem degradation on the dynamic of vegetation in the Djelfa region-Algeria

Abstract

Steppe ecosystems in Algeria, known for their distinctive biodiversity and delicate balance, are facing increasing degradation caused by human activities and climate change. This study aims to analyze the effect of ecosystem degradation on the composition of plant communities. To carry out a detailed floristic and ecological analysis of the vegetation in our study area, we developed a plant typology using two multivariate statistical methods. The first technique used is Correspondence Factor Analysis (AFC), which revealed the phytoecological relationships between the different groups of plants as well as the main ecological factors that explain their differences. This analysis led to the identification of five vegetation units, each corresponding to various plant formations: forest, pre-forest, steppe, degraded steppe and pre-Saharan steppe. These results indicate an evolution towards steppe formations such as those dominated by Stipa tenacissima L., which are often accompanied by varying degrees of degradation. The proliferation of species such as Arthrophytum scoparium (Pomel) Iljin., Astragalus armatus Willd.  and Thymelea microphylla Coss. & Durieu., which are often considered widespread in these emerging plant communities, demonstrates the resilience and adaptability of some species in response to environmental changes. As a result, some plant species that cannot adapt to new environmental conditions disappear, which upsets the ecological balance.