渴望科学

阿姆斯特丹—在湄公河三角洲,农民在旱季能收获6—7吨的水稻公顷产量,雨季则为4—5吨,使用快速成熟稻种,每年可以收获三季。相反,西非稻农种植传统旱稻每年只能收获1.5吨的公顷产量,其他谷类产量更是不到一吨——与欧洲中世纪产量水平相当。

如此差异本可避免。事实上,农业技术——从效率更高的机械到更鲁棒的稻种——有潜力大量缩小产量差异,即便两地气候和生产者不同。

比如,一种新的非洲旱稻——非洲新稻(Nerica)能将年产量翻三倍。类似地,在过去四十年中,改良的喂养模式、高质量饲育和更好的兽医服务让全世界平均牛奶产量增加了一倍多。尽管如此,地区差异仍然巨大:新西兰的奶牛一年可产奶9000升,而热带地区的瘤牛只能产300升。

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