مدى تغير المناخ وذبذباته وعلاقاته بالتطور الحضاري والاقتصادي:السودان مثالا

Abstract

Since the later part of the sixties of the twentieth century a number of dry climate periods prevailed in the Sudan and in many parts of Africa, the duration of each period was generally not or than seven years interrupted by normal or even more humid climate... As a result, a number of conferences were held, and Nairobi conference, 1977, was the main one the problem was stated as climate change. But this paper disputes the term “change” and thinks the right concept should be climate fluctuations. The difference between the two terms lies in the fact that fluctuation is for a short period while changeis for a very long period measured by hundreds of years as was the case in the Pleistocene era. The paper,after studying the rainfall data for over a hundred years in the Sudan and some other countries including Britain, reached the conclusion that what had happened to climate in Sudan were fluctuation and not changes, and these fluctuations did not cause desertification,but cause indirectly land degradation, and that was primarily caused by overgrazing as the number of the animals vastly exceeded the grazing resources. The result was almost the depletion of the palatable plants while the other plants remained as they were except in the case of over cutting. Thus no desertification was noticed. Thus, the paper suggests for the prober management of the plant cover to stop over grazing,over cultivation and over cutting of wood.