【BBC地球脉动】沙漠 5

英语自学网

Hint:
       
       
       
        Namibia
英式拼写
Reptiles have armoured scaly skins that protect them from the stinging grains. For insects the bombardment can be very severe indeed. The only escape is below the surface. As the winds rise and fall, swirl and eddy so they pile the sand into dunes. These sand seas can be hundreds of miles across. In Namibia the winds have built some of the biggest dunes in the world. Star dunes like these can be 300 metres high. Grains, swept up the flanks, are blown off the crests of the ridges so it's only the tops that are moving. The main body of these dunes may not have shifted for 5,000 years.爬行动物的皮肤有鳞片的保护，可以使自己免遭沙尘针刺般的撞击，对昆虫来说，这种轰炸可能是致命的唯一的办法是钻到沙子里面，风起风息风旋风转，把沙子吹成了沙丘这种沙海有的直径可达几百公里。在纳米比亚，风形成了世界上最大的一批沙丘，像这样的星状沙丘，可能高达300米，两侧的沙粒被吹起来，吹过山脊，所以只有沙丘顶部在移动，这些沙丘的主体，可能已经5000年没有移动过。