In addition to the carbon savings in transportation, such foods rely on animal manure as fertilizer.

为了减少运输过程的碳排放，有机食品通常使用动物粪便作为肥料。

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Some plants would control pests and soil quality naturally, and humans helped by rotating their crops; if extra fertilizer was needed, manure usually filled in.

一些作物本身就具备防治病虫害、保持土壤肥力的功效，人类辅以轮种；即便需要添加一些肥料，大多用的是人畜粪便。

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Anaerobic lagoons treat manure on some animal feeding operations prior to application to crops as a fertilizer.

泻湖先将饲养动物的粪便加以处理，再当做肥料用于作物。

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Scotts plans to gradually introduce more gardening soil, fertilizer and bug killer made with natural ingredients, including animal manure and Sri Lankan coconut husks.

FORBES: Organic Miracle Needed

Should you still be a bull on fertilizer stocks--or is the bullish case a bunch of manure?

FORBES: Magazine Article

Other culprits include the application of fertilizer in the fall, when the ground is bare, and the spreading of manure on the surface, instead of into the soil.

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