A plateau is an area of relatively level high ground and a plain is a large area of flat land with few trees.
Can you translate this to english I might be able to help?
Found at the lowest point of a large drainage area, these seasonal, marsh-like ponds collect and store water from rain and runoff. Unlike vernal pools, playas generally fill when temperatures are unsuitable for plant growth, and often the water is salty, alkali or both.
source- google
