|The Mara River Basin, which crosses the borders of both Tanzania and Kenya.|
|A section of the Mara River Basin during the drought season.|
|Lake Victoria at sunrise http://www.etravelphotos.com/photo.php?pid=903|
There are four different types of soils found in the Serengeti National Park which are black cotton, alluvial, granitic, and lateric soils. The black cotton soil is found mostly on the western corridor and is comprised of black clay. The soil of the park is highly influenced by the ash deposits of the volcanoes on the Ngorongoro Highlands making it a very particular type of soil containing many types of salts, such as potassium, sodium, and calcium. During the wet seasons, the salts from the soil are swept down into the soil where they dissociate and accumulate less than a meter below the surface. There, the precipitates form a hard layer known as a “petrocalcic horizon”, which is the lateric soil, making the soil impenetrable to tree roots, thus hindering the growth of trees on the plains, and reversely, the thriving of grass.
The underlying granitic rocks are highly resistant to weathering also due to the effect of the ash deposits from these volcanoes, making the weathering process slower than usual in this area.
|Savannah soil profile|
|Black cotton soil of Tanzania http://civil-engg-world.blogspot.com/2012/06/black-cotton-soil.html|
Sources for information: