Eating Beef: Cattle, Methane and Food Production

吃牛肉：畜牛、甲烷及糧食生產

Åsa K Wahlquist

《Asia Pacific Journal of Clinical Nutrition》 22卷1期 (2013/03) Pp. 16-24

https://doi.org/10.6133/apjcn.2013.22.1.04

摘要

因為畜牛會產生溫室效應的甲烷氣體，故一些名人提倡少吃肉或是成為素食者，以減少全球暖化。這牽涉幾個問題包含：世界上許多原先放牧畜牛的那些草原會變成如何；替代蛋白質如何被生產以及那個產物的溫室結果將會是什麼？這歸結到生產系統。世界上的農地有70%是草原，從草原生產糧食只有一個方法，就是放牧反芻類動物。假如沒有在草原放牧家畜，原生或是野生反芻類動物會遷移進去，也產生甲烷。餵食畜牛高品質穀類的做法是更難站得住腳的。以植物性蛋白替代動物性蛋白，例如大豆，需要使用較多耕地、水、燃料及化學物質。一個較合理的糧食系統應該是將牛群放養在草原上，而不餵食牠們高品質穀物。這樣反而有更多現行的作物可提供人類食用。

關鍵字

畜牛 ； 甲烷 ； 草原 ； 穀物餵養

並列摘要

A number of prominent people have advocated eating less meat or becoming a vegetarian to reduce global warming, because cattle produce the greenhouse gas methane. This raises a number of questions including: what will happen to the grasslands that much of the world's cattle currently graze; how will alternate protein be produced, and what will the greenhouse consequences of that production be? It comes down to production systems. About 70 per cent of the world's agricultural land is grassland, and the only way to produce food from grasslands is to graze ruminants on it. If domesticated animals do not graze the grasslands, native or feral ruminants, which also produce methane, tend to move in. Feeding high quality grain to cattle is much less defensible. Replacing animal protein with plant proteins like soybeans necessitates more cropping land, water, fuel and chemicals being used. A more rational food system would raise cattle on grasslands but not feed them high quality grains. Instead more of the currently grown crop could be devoted to human consumption.

並列關鍵字

cattle ； methane ； grassland ； grain-fed

參考文獻

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