Leaves which fall to the ground decay and become of the soil

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• 英语翻译When nature is left alone,a balance is reached among the animals and plants living in one area.But when man starts his work in nature,the balance is likely to be destroyed.He grows a crop and takes it away to eat then there are no dead leaves to fall on the ground,holding water while it sinks into the surface,or decaying(腐烂) and adding humus(腐殖质) to the soil.Unless a farmer acts with knowl- edge and skill,he is therefore most likely to make the la
• Leaves which fall to the ground decay and become of the soil
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