The bird is biotic and the roof it is sitting on is abiotic.

The light of the sun which is an abiotic component is giving the tree, which is also abiotic, light so it can photosynthesize.

The fish is biotic and it is swimming in the water which is abiotic, so it can survive.

The rock is abiotic and the fungus is biotic. The fungus eats the minerals from the rocks.

In this ecosystem, what is a natural event that could affect one or more other spheres? Explain 

Rain is a natural event that can affect other spheres. Rain is a hydrosphere that provides lakes, rivers and streams for the atmosphere, so animals (the biosphere) can drink from it.