Biodiversity (biological diversity) is the variety of all living organisms in an area, including the different genes, species and ecosystems they form. Malaysia is one of the world's megadiverse countries because of its tropical rainforests and coral reefs.
Three levels of biodiversity
- Genetic diversity — the variety of genes within a species (e.g. many varieties of rice or durian). It allows populations to adapt to change.
- Species diversity — the number and variety of different species in a habitat. A tropical rainforest has very high species diversity.
- Ecosystem diversity — the variety of habitats or ecosystems in a region, such as forests, mangroves, rivers and reefs.
Example
A single hectare of Malaysian rainforest may contain hundreds of tree species, plus insects, birds and mammals — an illustration of high species diversity.
Importance of biodiversity
Biodiversity supports human life and keeps ecosystems stable:
- Provides food, medicine, timber and raw materials.
- Maintains ecological balance through pollination, decomposition and nutrient cycling.
- Supports ecotourism and has scientific and educational value.
Threats and protection
Biodiversity is reduced by habitat destruction, deforestation, pollution, over-exploitation and introduction of invasive species. When a habitat is cleared, the many species that depend on it may become endangered or even extinct, and once a species is lost it cannot be recovered. Biodiversity is protected by gazetting national parks and wildlife reserves, replanting forests, controlling invasive species and enforcing conservation laws such as bans on hunting protected animals. Individuals can help by not buying products made from endangered species and by supporting reforestation.
Key idea
Biodiversity has three levels: genetic (within a species), species (between species) and ecosystem (between habitats).
Remember
High genetic diversity gives a species a better chance to survive environmental change.