Savannah
Savannah (alternatively, savanna, from the Spanish zavana, çavana or sabana) from the Taino zavana initially described treeless plains in tropical America and subsequently a tract of low-lying damp or marshy ground. More recently, the term refers to open mixed grassy woodlands in tropical or subtropical regions where the trees are spaced so that the canopy does not close. The open canopy allows the ground to support an unbroken layer of grasses.
Savannah landscapes can be classified on a continuum between open savannahs—where grass prevails, and trees are rare—and wooded savannahs, where the tree density may border on what one might classify as open woodland or forest.
While savannahs are subject to wildfires, those found in tropical Australia and New Guinea appear to have resulted from 'fire-stick farming' — intentionally controlled low-intensity burning confined to the herbaceous layer that does minor long-term damage to mature trees. Such fires suppress tree seedlings, preventing a continuous tree canopy — which would prevent grass growth from developing — and creating a mosaic of habitats that probably increased biodiversity. The removal or alteration of traditional burning regimes has seen many savannahs replaced by forest and shrub thickets with little herbaceous layer.
