الأودية الداخلة إلى منطقة الحرم بالمدينة المنورة

الملخص EN

The grater city of Al-Madinah occupies a lowland basin surrounded by mountains.

Because of its centerbutal drainage pattern, wadis come from varies directions towards the center, which is known as floods gathering point.

Most of the wadis try to reach this point, but they fail to do so because of the lava formations at the east and south, and the channals of the major wadis such of Qana in the north and east, and AlAqiq in the west.

Only six wadis cross the sacred zone of Madinah.

Three of them are major ones: Qana, Al-Aqiq, and Bathan.

The others are minor ones: Ranwonana, Mdhainuib, and Mahzour.

The major wadis bring to Madinah a considerable amount of surface water (13.94) million cubic meters per annum.

The morphometeric characteristics of the major wadis can be summarized as follows: 1 - Drainage density: 0.3 kmAkm.2; 0.28 km.\km.2; and 2.75 kmAkm? for the wadis of Qana, Al-Aqiq, and Bathan respectively.

2- Dissection ratio: 7.19; 4.29; and 2.75 for the wadis of Qana, Al-Aqiq and Bathan respectively.

3 - Bifurcation ratio: 4.2; 3.7; and 2.75 for the wadis of Qana, Al-Aqiq and Bathan Respectively.

The minor wadis of Ranwonana, Mdhainuib, and Mahzour are laying in the upper part of the basin of Bathan.

Thus constituting the upper sources of the wadis Bathan.

The field trips and investigations have reveled that all of the major wadis have experienced some drastic changes in their morphological characteristics especially in the vicinity of the built up area of the greater city of Al-Madinah.