IMPACT OF THE PALM GROVE AND THE BUILT DENSITY ON THE URBAN MICROCLIMATE IN OASIAN ENVIRONMENT

Abstract

The oases have always been the place of human regrouping in search of an adaptation to the harsh conditions of Saharan regions (drought, severe aridity of the climate, etc.). The palm grove, in these hostile areas, constitutes a fundamental element in the balance of their ecosystems, thus making the relationship of its local populations with this palm grove vital due to its impact on their economic, environmental and social experience. Our case study is Biskra city, an oasis city by excellence in the South-East of Algeria because of its geoclimatic characteristics. This city is distinguished by its large palm grove which contains a set of so-called “traditional” neighborhoods. By their originality, these traditional districts are characterized, on the one hand, by their rather compact shape, and on the other one, by their harmonious insertion within the palm grove, which has been a major element of thermal regulation. We are witnessing currently a real atrophy of this palm grove as a result of an accelerated and thoughtless built urban sprawl. In addition to the factor of universal climate change, the microclimate, characteristic of the traditional districts of old Biskra, was then radically changed. The main purpose of this article is to report on the assessment of the contribution of the palm grove and the compactness of the building in improving climatic conditions in traditional fabrics, and to quantify the impact of the reduction. of the extent of the palm grove on the microclimate of these districts. It is based on an experimental study employing a numerical simulation of microclimatic conditions, using the threedimensional software ENVI-met. This study allowed us to gather countless information concerning the notable effect of traditional dense forms inserted in a palm grove on microclimatic variables and to quantify this effect.