There are only a couple abiotic factors in the savanna that you can really recognize.
One is fire. Fire is the most important abiotic factor to the savanna. without the constant fires a tropical savanna could turn into a tropical forest!
Another abiotic factor is soil. There really isn't much to say about the soil except that it is real important to plants and the animals that eat the plants
Air and water are the two last abiotic factors in the savanna. Everybody knows the importance of air to any biome. Without it survival would be impossible. Water is just as important.During the summer or dry season there really isn't a lot of water.Trees store water during the wet season so they have water during the dry season. Just like air, without waterthe chances of living are very slim.