In general, when one moves farther west within the south region, are more bayous there is less plain there is less rain there are more mangroves

The correct answer is - there is less rain.

If we take the south part of the country, than we can simply look at it as being more rainy on the eastern side, and being less rainy on the western side. While in the eastern side the landscape will be predominantly green, with marshes, swamps, and bayous, as we move towards the west, the landscape will gradually become more yellowish, vast grassy plains that have season rain,and for most of the year are dry, and if we continue even more to the west we we encounter semi-arid and arid places were rain is very rare and small in amount.