An Introduction To Ecosystems

Compost can be active in a variety of ecosystems, it happens in every environment.
What's Helping The Pile Decompose?
Inside a compost pile, microorganisms digest organic matter & turn it back into its inorganic nutrient form: carbon dioxide, water, & compound forms. This process is critical to composting because the microorganisms release nutrients in a form that plants can absorb & use.
Primary Consumers
Microorganisms, like bacteria, fungi, actinobacteria, earthworms, snails, & slugs, that feed on dead plants and animals to break up the organic matter.
Secondary Consumers
These macrorganisms, like protozoa, mold mites, & nematodes, feed on primary consumers. They keep populations of the primary consumers in check, to aerate the pile as they move through it, & enrich the pile with their excretions.
Tertiary Consumers
Centipedes, ground beetles, & predatory mites feed on secondary consumers, keeping populations in check, they aerate the pile as they move through it, further enriching the material, aiding the decomposition process.
Inside a compost pile you will find a variety of microorganisms:
  • Bacteria make up 80-90% of the microorganisms found in compost. They’re the smallest of the microorganisms in the compost pile, but are the most nutritionally diverse, meaning they can break down the largest number of organic materials.
  • Actinomycetes break down cellulose, lignin, chitin & proteins, which are more complex, found in materials like tree bark, wood, & newspaper. Most bacteria & fungi cannot break these down, just as actinomycetes cannot compete for most of their simple carbohydrates. They are also responsible for the pile’s pleasant, earthy smell.
  • Fungi are found in the latter stages of composting, they move to the outside of the pile to avoid the heat. Fungi break down cellulose & tough debris that bacteria have a hard time processing, things that are dry, acidic, or high in nitrogen.
  • Protozoa and rotifers feed on bacteria & fungi in the compost pile, but only make up a small percentage of the pile. They play a very small role in composting.

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