Drought Impact on the Olive-Trees in the Tunisian Jeffara
摘要
In spite of its high adaptation capacities and also its aptitude to grow in the arid areas, the olive-tree did not escape to the negative effects of the drought resulting usually in a fall of the production, the accentuation of the alternation production cycle and in some ultimate cases by the withering of the olive-tree. This work concerned the study of drought impact on olive-growing plantations in the Tunisian Jeffara (province of Medenine). It aim at characterizing the rainfall deficit observed in the study zone during the period 1999-2002, and to identify the meteorological drought intensity differences in the same region. The rainfall data from two gauging stations: Medenine (1903-2002) and Zarzis (1908-2002), were analyzed using several indices. It was found that drought is a recurring phenomenon in the study zone. The occurrence of successive dry years is less frequent in the costal zones than in the other localities. The year 2000-2001 is founded the most exceptional dry period which affected negatively the development and the growth of the olive trees resulting in partial or complete loss of a large number of olive-trees.