Which biome contains large populations of grazing herbivores, few species of birds, and deep, rich soil?

The savanna grasslands of Africa is an example of a biome that supports large populations of grazing herbivores, few birds etc. The savanna supports grazing animals such as wildebeests, antelope, zebra and many other grazing species. There are few species of birds because the landscape there is almost void of trees. Only a few species of acacia dot the extensive grassland.