Manure has become a minor source of nitrogen in all major agricultural countries.

在主要的农业国家动物粪便已经不是氮肥的主要来源。

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The liquid manure is still a major source of environmental pollution, although the way of separating solid and liquid manure reduces the environmental effect in certain extent.

虽然采取固体粪便与液体粪水相分离的方法在一定程度上减少了对环境的影响，但液体粪水仍是污染环境的主要来源。

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During the time of traditional agriculture in Guangdong, the main manure source of mountainous areas was ash, while in the plains, the main manure source was the river filth.

传统农业时代广东地区山区和平原分别以获取灰粪和泥肥作为主要肥源。

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It results from the 1.6 billion people that do not have any access to electricity whatsoever, the 2.4 billion that have almost no access to electricity and still burn wood and manure as their main source of energy, and the 3 billion new people that will be born by mid-century who will need electricity.

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