Apart from plants and animals, microbes from a permanent biotic component in an ecosystem. While plants have been referred to as autotrophs and animals as heterotrophs, what are microbes referred to as? How do the microbes fulfil their energy requirements?
Productivity, decomposition, energy flow and nutrient cycling are integral ecosystem features. Plants and animals play important roles in productivity. Some microbes play a role in productivity, and some are autotrophs, e.g., algae and chemosynthetic bacteria. Most of the microbes are heterotrophs. Parasitic microbes get nutrition from the host on which they depend. Many microbes are saprotrophs. They get nutrition from detritus, i.e. they are an important part of the detritus food chain.