True of false decay always happens at the same rate in ecosystems?

Answer 1

false

Decay of dead plant and animal material is normally accomplished by yeast, bacteria and fungi which have evolved to break down the cellular material for food. However, some decay is "built-in" to the plants or animals in the form of enzymes which decompose the dead cell material. Also, there are insects, worms and other animals who assist in eating and recycling dead organisms.

The rate of breakdown is dependent on many things, for example:

1. Temperature - colder is slower, but too hot can kill the microrganisms or disable the enzymes needed for decay

2. Available liquid water - the microorganisms and enzymes need water to both live and to operate their digestion chemistry. Decay proceeds very slowly in deserts.

3. Number and type of microorganisms

4. Available oxygen - some organisms need oxygen to live, others do not

5. Other chemicals in the environment which can inhibit the action of the decay microorganisms.

Some materials such as polymers can be broken down by light, especially ultraviolet light from the sun. So the rate of photodegradation is determined by how much sunlight the material gets.

Some materials simply dissolve in water, thus the amount of water available changes the rate of "decay".