In order to provide biodiversity conservation on landscape and regional level,  green belts would ensure migration of many species of animals and plants, especially of those with small and isolated populations from the territories subjected more drastically to desertification to the territories where climatic conditions are closer to steppe ones (around green belts and at heights). That's why we consider that spatial evaluation of indexes that demonstrate aridity degree at the level of different components of ecological network would contribute to ecological balance conservation. In this context, cartographical modeling of de Martonne (Im) aridity index by Geographical Informational Systems allows realization of the proposed objective.