Why is the Sahara dessert considered a ecosystem?

What are the 3 advantages of tourism? Where is lake Baykal located? What was likely the reason for changing the environment and building the St. Lawrence Seaway? Why Bangkok known as city of angels? When did the Hoover Dam open? How has the Golden Gate Bridge been made stong and stable? Is Waterfall a potential resource? What does liberty media owns? Where does the chunnel run? What is a large amount of water spread from a river that covers an area that is normally dry? What are the environmental factors soil tides salinity altitude elevation of the rainforest? Where can you find laws and licensing information regarding Auto Repo for the state of Utah? What is a large area partially enclosed by salt water? What is the biltmore shores sinkhole? What two countries does the Aegean sea separate? The meaning of maira? Juan and jamal collectes 39.00 for tickets to the science museum adult tickets cost 7.00 and childrens tickets cost 5.00 how many adults and how man children plan to go visit the museum? When did fermin lasuen come from? How reservoir impact environment? When did Ionian Revolt happen?