Spatial variation of water-climatic balance and its relationship to desertification in northeastern Libya

Abstract

the water -climate balance is one of the environmental problem that is suffers from affecting the regions semi-arid and semi-humid in the Northeastern Libya .In those regions, the amounts of rainfall varied specifically. The total evaporation amounts exceed the rainfall, causing the water deficit that reached its annual quantity is in Bennah (1174.5 mm.), Shahat (635.9 mm.), Derna (996 mm.), AL Fatah (943.8 mm), and (1619 mm.) in the Southern of the ALjabal Al-Khader. Monthly and seasonally averages shows that there are large water deficit in all seasons, that rangingat summer season to (190.3 mm) in Baninah, (165.2 mm) in Shahat, (165.7 mm) in Dernah and (173.mm) in Alfatah. As well as ,there is a slight water surplus in winter season ranging from (7.5-9.6 mm) in Baninah, (8.4-84.3 mm) in Shahat, (6.6-8.9 mm) in Dernah and (36.7-37.9 mm) in Alfatah. Hence the natural ecosystem in these areas are characterized by weakness ,and its high rate of its ability to desertification increases to about (95.1%). Due toover exploitation ,and  Many indicators of desertification are prevailing at these areas due to human activates, over exploitations,  e.g; drought, gully erosions, and degraded of natural vegetations. And in addition to sand dune, dust storms occurs and then encroachment on agriculture , postal lands, as well as increased the salinity at the ground water in the regions. This study depends in its methodology, in addition to many sources ,and references, several techniques had been applied ,such as (Emberger)of climate -veg. region classifications in the Mediterranean Basin as well as (Turc) equation for estimations total evaporations .In the last ,the study has also consisted several important conclusions and recommendation to combat the desertification and degradation in  the study  area lands.