Palm trees reuses as sustainable element in the Sahara. The case of Ziban, as self-sustainable urban units

摘要

The lower Algerian Sahara is experiencing an unprecedented urban growth, causing a socio-spatial upheaval and an ecological imbalance of oasis ecosystems that are embodied in the detachment of the palm trees from the urban areas. This detachment actively participates in the increase of the Urban Heat Island, as well as the over-urbanization on the account of farmlands. Hence the abundance of palm groves, participates in the activation of desertification. Yet urban growth in the Saharan regions had been done since a long time taking the shape of oasis networks composed of small centres that functioned as "oasis villages.", [1] the ecological growth took place based on three variables, the first population, the second human settlement: Ksour plural of Ksar and Dachra, the former is more urbanized than the latter, and the third palm trees which was both a terrain roof minimizing solar gain and a windbreak protecting human settlements from sandstorms. The Ziban, plural of Zab, and the Amazigh appellation of oasis, represented one of the oasis networks. These variables would be the subject of study of the quantitative relationship between these three parameters. This relationship can give us the first measures in designing sustainable urban units friendly to that too hostile environment. Our work will be based on the comparison of 2009 statistics with 1904 statistics, because this year represents the initial state of the oases of Ziban. Finally we will try to propose a remedial project through tourist tours to reunite this Ziban.