撒哈拉沙漠 英文简介

撒哈拉沙漠 英文简介
撒哈拉沙漠 英文简介

撒哈拉沙漠 英文简介
Sahara desert
THE Sahara desert is the world’s largest desert area.It extends from the Africa’s Atlantic Ocean side to the Red sea and consists of the countries of Morocco,Algeria,Tunisia (突尼斯),Libya,Egypt,Mauritania (毛里塔尼亚),Mali,Niger（尼日尔）,Chad（乍得）,and Sudan.It is about 5,200 miles long.Overall,the Sahara desert covers 3,500,000 square miles.
The geography of the desert is varied.In the west,the Sahara is rocky with varied elevation.It does contain underground rivers,which sometime penetrate the surface,resulting in oases.
The central region of the Sahara has more elevation than the other areas,with peaks such as Tahat.Even though the area lacks rainfall,these peaks are snowcapped during the winter.The eastern part of the Sahara,the Libyan desert,is dry with very few oases.
The Sahara’s climate is very hot and dry.Although it is very hot during the day,it does become cold at night.
The Sahara used to be a fertile area in which elephants,giraffes and other animals grazed.It is estimated that in 4,000 BC,the climate began to get drier.The fertile landscape dried up and the desert widened,creating the form that appears today.
(SD-Agencies)

Sahara Desert (ecoregion)
The Sahara Desert is an ecoregion covering part of the Sahara.
The Sahara is the world's second largest desert (Antarctica is the largest) and is located in northern...

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Sahara Desert (ecoregion)
The Sahara Desert is an ecoregion covering part of the Sahara.
The Sahara is the world's second largest desert (Antarctica is the largest) and is located in northern Africa. It stretches from the Red Sea to the highlands of Ethiopia. However, the Sahara encompasses regions significantly different from an ecological perspective. The surface of the desert ranges from large areas of sand dunes (which are called erg), to stone plateaus (hamadas), gravel plains (reg), dry valleys (wadis), and salt flats. The northern and southern margins also receive more rainfall and have greater vegetation than central Sahara. The very scarse rain (less than 25 mm and even less than 5 mm per annum in the east) can fall in any season and in a very irregular way : some areas may receive no rain for years then suffer intense storms. Some areas encompass vast underground aquifers resulting in oases, while other regions severely lack water reserves. Some mountains (Ahaggar, Tassili N’Ajier, Tibesti, Aïr) also rise up in the desert and receive more rainfall and mostly present slightly cooler summer temperatures.
For such reasons, the great Sahara may be divided in several ecoregions and each of them be separately described. Other ecoregions are

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