至到二十年前,墨西哥靠雨水维持生产的地区仍能保证粮食自给自足,除满足国内需要外,多余的还可以出口.然而今天的墨西哥,由于条件变化,已不得不进口数量众多的各种农产品,其中主要是粮食,以供人的消耗.这些变化是,无常的降雨循环;人口增长率超过粮食生产率;缺乏货款和资金,这些变化对土地资源提出了更高的要求,尤其是对靠降雨维持生产的农业区,这些农业区大多分布在墨西哥的干旱、半干旱地区.政府为增加生产已提出扩大农业区的计划,新开发的土地,必须应用新技术,例如采用牲畜、拖拉机两用犁地工具. By 20 years ago, Mexico could still guarantee food self-sufficiency in areas that depend on rainwater to sustain its production and, in addition to meeting domestic needs, can export surplus. However, due to changing conditions, Mexico today has had to import a large number of These kinds of agricultural products, mainly food, are for human consumption These changes are impermanent rainfall cycles; the rate of population growth exceeds that of food; the lack of money and funds, these changes place a higher demand on land resources, Most of these agricultural areas are distributed in the arid and semi-arid regions of Mexico, and the government has proposed plans to expand agricultural areas for increased production. Newly-developed land must use new technologies, such as the use of livestock and tractors Use plow tools.