Figure 2 illustrates the typical changes in soil organism numbers and soil plant available N levels that are typical when high carbon to nitrogen ratio organic material is added to a soil. In this case plant available nitrogen levels decease during the early stages of decomposition. However, due to continued soil organism respiration, carbon will leave the system as carbon dioxide leading to a surplus of soil organism nitrogen which will be released back into the soil. The nitrogen release rate however, is usually slow. This means that, just like low carbon to nitrogen ratio materials, the key to management is matching the nitrogen release with crop requirement.

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