التغيرات المناخية الحديثة واثرها على الغطاء النباتي في حوض وادي عربة الشمالي

Recent climatic changes and their impact on the vegetation cover in the northern Wadi Araba basin

The climatic effects that are associated with decreased precipitation and increased air temperature, especially in marginal environments, have serious effects on water resources, the vital environment and economic activities. General air circulation models indicate that the eastern Mediterranean will be negatively affected by the rise in greenhouse gases in the atmosphere, as rain will decrease and air temperature will increase. Jordan is currently suffering from a low amount of renewable water and low agricultural productivity, especially rainfed, as a result of the lack of rainfall and the high potential evaporative energy. Therefore, it is useful to study climate changes and evaluate their future effects on agricultural and pastoral production and water resources in different environments in Jordan. In this research, the general trend of annual precipitation and surface temperature was identified in the northern basin of Wadi Araba for the period 1971-2016, and the temperature and monthly rainfall were combined to calculate soil moisture and drought frequency using the presumption of drought severity developed by Palmer Drought Severity Index and to link climatic effects on the biological environment Five satellite images from the Landsat group for the period 1987-2015 were used to assess the general trend of vegetation cover areas in the upper part of the study area. The results of the analysis showed that the air temperature increased during the period 1971-2016 by 2.7 degrees Celsius, and that the rains decreased by 100 mm during the same period. Changes have been rapid and tangible since the end of the twentieth century. Through the calculations of the monthly water balance for the upper section of the soil, it was found that there was a significant decrease in soil moisture, which amounted to about 0.8 mm / year in this section, which indicates serious effects on water and agricultural resources. The results also indicate a significant increase in the severity of drought, as shown by Palmer's wife, especially in the period that followed 1999. The results of the analysis of satellite visuals for the years 1987, 1998, 2002, 2014, 2015 indicate a shrinking of the area of ​​green lands and a very large increase in the area of ​​barren lands. It was found that the area of ​​barren lands increased by 150% between the beginning of the twentieth century and 2015. The area of ​​pastures, forests and field crops decreased at a similar pace. If this general trend of climate change continues, this will have serious effects on land productivity, whether with regard to field crops or pastures, and will also lead to a significant decrease in the amount of water available for various purposes, a rapid decline in groundwater recharge, and the drying of many springs. Climate change will have devastating repercussions and effects on the large-scale investments in apple cultivation, which are widely spread in the eastern part of Shobak. an‎d counts! This category should support scientific research projects whose results are in their favour!!