Another factor is climate change - livestock rearing produces methane, which is 23 times more powerful than carbon dioxide in global warming terms, according to Lord Stern.

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And he found that he could cut the dropout rate dramatically by doing away with homework and incorporating income-generating activities such as fish cultivation and livestock rearing in the school curriculum.

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More than 90% of Loliondo's Maasai depend on rearing livestock on seasonal grasses there.

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There has long been opposition to the prospect of a gold mine and processing plant being built at Skouries in the Halkidiki peninsula, with some residents objecting to what they say will be the destruction of the environment and of pristine forest in the area, leading to the loss of tourism and other local activities such as farming, the rearing of livestock and fishing.

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