Sahara Dert 世界的沙漠-撒哈拉
撒哈拉英⽂介绍Sahara Dert
The Sahara Dert， covering most of North Africa， is the largest dert in the world. From north to south the Sahara is between 800 and 1，200 miles and is at least 3，000 miles （4，800 km） from east to west. Due to the massive size of the Sahara， Africa is split into two regions： that which lies above or forms part of the Sahara and the rest of Africa south of the Sahara. On the west， the Sahara is bordered by the Atlantic Ocean and on the east by the Red Sea， and to the north are the Atlas Mountains and Mediterranean Sea.Over 25 percent of the Sahara's surface is covered by sand sheets and dunes.撒哈拉沙漠是世界上的沙漠， 25％的沙漠被沙⼟和沙丘覆盖。
Climate ⽓候
课程评价的功能
The Sahara's climate consists of basically two sub-climates， a dry subtropical climate in the north and a dry tropical climate in the south. The dry tropical climate is generally characterized by mild， dry winters， a hot dry ason just before the rainy ason， and an annual temperature cycle. The dry subtropical climate， however， is characterized by annually high temperature ranges， cold winters， hot summers and two rainy asons. There is a narrow strip in the western portion of the Sa问道于盲
告别了hara， along the coast， which generally has cool temperatures compared to the rest of the Sahara becau of the influence of the cold Canary Current. 撒哈拉沙漠包含了2种⽓候， ⼀种是北部的⼲旱亚热带⽓候，令⼀种是南部的⼲旱热带⽓候。
ppt的做法 Plant Life 植物⽣活
The Sahara is sparly covered with various types of vegetation ranging from grass， shrubs， and trees in the highlands to halphytes， which are saline-tolerant plants found in saline depressions. One characteristic of the vegetation found in the Sahara is that the species must be able to adapt to unreliable precipitation and excessive heat. 草丛，灌⽊和树⽊都可以⽣长，这些树⽊的特点是能承受巨热和盐碱地带。
杂粮窝窝头的做法撒哈拉沙漠⾥的动物
冬天跑步好吗Animal Life 动物⽣活
Some of the mammal species found within the Sahara are the gerbil， jerboa， Cape hare， the dert hedgehog，dorcas gazelle， dama deer， Nubian wild ， anubis baboon， spotted hyena， common jackal， sand fox， Libyan striped weal， and the slender mongoo. The Sahara also c
ontains over 300 species of migratory bird populations along with water and shore birds and various other types of birds. Some of the most common birds are ostriches， raptors，cretary birds， guinea fowl， Nubian bustards， dert eagle and barn owls， sand larks， pale crag martins， and brown-necked and fan-tailed ravens. 哺乳动物，鸟类都可以找到。
The People ⼈类
The Sahara Dert covers over 3.5 million square miles and has only 2.5 million inhabitants - roughly 1 person per square mile （0.4 sq km）- which is one of the lowest population densities on earth. Wherever abundant food and water sources occur， one will find relatively large mass of people and wildlife. On the whole， the Sahara is one of the harshest environments known to man. 居住⼈⼝极少，⼤约每⼈占地0.4平⽅公⾥，是世界上最少的⼈⼝密度。
Many rearchers have gone into the Sahara looking for clues as to how long ago humans began inhabiting the dert. According to archeologists， the Sahara was much more denly populated thousands of years ago when the dert's climate was not as harsh as it is today. Fossils， rock art， stone artifacts， bone harpoons， shells and many other items have been found in areas which today are considered too hot and dry to inhabit. This suggests that the areas were quite hab
itable thousands of years ago， but that the climate of the Sahara has since changed drastically. The artifacts found were located near remains of giraffe， elephant， buffalo， antelopes， rhinoceros， and warthog， as well as the remains of fish， crocodiles， hippopotamus and other aquatic animals which suggests that thousands of years ago water was quite abundant in the Sahara. 很多研究者经常深⼊撒哈拉去寻找⼈类是多久以前就在沙漠中⽣活了。 据历史学家调查，在千⽅年前的撒哈拉，⼈⼝密度⽐现在要⾼，是因为那时的沙漠的条件没有现在那么险恶。
五行八作 The majority of the people living in the Sahara Dert are nomads， which means that the people continuously move from region to region in arch of better living conditions. It is believed that the first nomadic peoples came to this region after domestic animals were introduced to the Sahara 7，000 years ago. Rearchers believe that sheep and goats were introduced to the Sahara region by the Caspain culture of northern Africa. 居住在沙漠⾥的⼤部分是游牧民，也就说他们不停的迁移，为了找到更适合⽣存的环境。
Evidence suggests that the Sahara accumulated diver groups which quickly formed den populations throughout the region. The majority of the groups lived parately， but depended on each other for trade. External trade developed gradually and the mobility of the nomads certainly contributed to the growing success of trade with other countries and continents. For example， Maur
统考成绩
itania contained valuable copper resources and as a result， this copper was traded to the
Bronze Age Civilizations of the Mediterranean. 这些游牧民族也靠和外界的较易⽣活。
