(a) Meaning of a lake: A body of water, accumulated in a depression or basin and surrounded by land
(b) Formation of lakes by wind erosion:- Occurs mainly in the arid regions - rocks deeply weathered - loose non-consolidated soil runs deep below surface no wind breaks - wind speed is high - winds have strong erosive power - wind deflation sets in - continuous action of wind deflation creates a hollow - eddy action of the wind further widens and deepens the depression/hollow - water table is reached-deflation ceases when the water table is reached water seeps out to form a lake - lake is usually small and shallow-excessive evaporation makes the water salty - e.g. Quattara Depression in Egypt, Great Basin of Utah, USA
(C) Benefits of lakes to man: - means of transportation- source of fish - source of common salt-source of water for reared animals - regulates flow of rivers - attracts settlements in arid and semi - arid regions - reserves water for HEP generation - source of domestic water supply - tourist attraction sports and recreation - health resort - moderation of climate - for employment - for irrigation water for industrial purposes - centres for aquatic research.