by Dr Ngo Kang Min
Tropical forests are known for their extreme diversity of living things, both above and below ground.
In Singapore, researchers have found more than 350 species of trees within a 2 hectare area of primary forest. In comparison, a 16 hectare forest on the eastern coast of the US has 76 tree species.
Even within such a small and highly-urbanised country like Singapore, there is still a lot of biodiversity remaining, and more to be discovered.
Secondary forests are forests that developed over land that was previously cleared of forests.
Although secondary forests usually have lower diversity than primary forests, they have great importance in providing ecosystem services and serving as buffers and refuge for the remaining primary forests.
They provide habitat for numerous plants and animals, filter polluted air, clean out rain water, reduce floods, and contribute to our well-being (forest bathing, walking / running through a forest).