الخلاصة:
Algeria is one of the most vulnerable countries to the observed and projected variability and climate change. Various studies on this subject indicate that there is a clear tendency towards drought In these regions this hazard poses a real threat for development, and Algeria among the countries that suffers the most from this climate risk. The years 89 / 90,96 / 97,2007 / 2008 had a very significant rainfall deficit and had serious repercussions on all economic sectors.Which is therefore reflected in the medium and long term on the economic and social development of the country. Taking into account the risk of drought linked to climatic variations will undoubtedly mitigate the harmful consequences. This study aims to identify with some accuracy the impacts of climate variations on the evolution of vegetation in Constantinois, and to show the relationship between climatic variables and their variations (rainfall, climatic and water balance) and cereal production. in the wilaya of Oum Bouaghi on the one hand and evolution of the forest cover in the wilaya of Skikda on the other hand and in order to reach this objective a descriptive and probabilistic statistical approach was adopted. The work was carried out over a period from 1976 to 2012 applied to six climatic stations and five rain gauges, The following points were discussed: the climatic regime prevailing in the study area, the rainfall and climatic variability at monthly scale during the rainy season and the results show:
There is a strong correlation between annual rainfall totals during the growing season and cereal production. That the agricultural deficit fluctuates from one year to another as well as throughout the life cycle of winter cereals in relation to the very limited climatic potentialities in wilaya of oum El Bouaghi And that probably all forest species will be more exposed to disease and pest attacks, as well as the extension of areas hither to little or not affected by forest fires.
