Conditions that promote karst development are well-jointed, dense limestone near the surface; a moderate to heavy rainfall; and good groundwater circulation. Limestone (calcium carbonate) dissolves relatively easily in slightly acidic water, which occurs widely in nature.
Crowther said first he had to figure out how many trees are on Earth and that number was far more than anyone expected: 3.04 trillion trees, according to a study published Wednesday in the journal Nature. 14 Photos Trees Around The World.
How Many Languages Are There In The World. There are more than 7000 different languages are spoken by the people around the world today. Anyhow 90% of these languages are used by less than 100,000. If you ask a question, how many languages are there in the world, it can be answered with the number 7000+.