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Waste and dead material will naturally decay. Microorganisms play an important part in decomposing waste material and animal carcasses so that the chemicals from which they are made can be used again by plants. The same material is recycled over and over again and can lead to stable communities.
In situations where something is removed from the system, the whole food web can break down as the plants do not get the nutrients they need to thrive. That is why farmers need to use fertilizers - as the crops are taken away, no nutrients are put back into the soil naturally so without fertilizers, the next crops would not be as good.
The compost heap in your garden is an artificial form of nature's recycling system. By placing uncooked food waste like vegetable peelings and grass cuttings in a pile or in a composting bin, they can rot down and decay and then be added back to the soil. Humans create vast amounts of rubbish which is taken to landfill sites. Part of the rubbish is garden waste. When this decomposes in a landfill site, the nutrients are wasted. This is poor management. Most local authorities run composting schemes where the garden waste is separated and sent for composting instead of to landfill sites.
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