For example, nitrogen can be a fertilizer, but it can stunt plant growth when nitrogen comes out of the air in acid form.

举例来说，氮可以用作化肥，但其一旦以酸的形式离开大气，就会阻碍植物生长。

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Fertilizer use differs from country to country, and from too little to too much. Nitrogen and phosphorus can produce big crops. But they can also pollute water and air.

肥料的使用因国而异，并且使用的多少也有差别。氮和磷能使作物长得粗壮。但同时也会对水和空气造成污染。

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The pollutions were related to soil, fertilizer, irrigation water and air.

污染和土壤、肥料、灌溉水及空气有关。

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Sanergy employees empty the toilets each day, taking an air-tight container of waste to a Sanergy processing facility where it is converted to biogas and fertilizer that Sanergy plans to sell to commercial and small farmers.

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