肯尼亚和中国农业资源投入与农业单产水平变化

当前，肯尼亚和中国在生产足够粮食以保障粮食安全方面都面临着严峻的挑战。尤其是对于肯尼亚而言，因为其2100年预测的人口将达到2018年的1.4倍，且其粮食生产在过去并没有大幅度的改善。而中国近些年粮食生产能力显著提高。本文系统分析了肯尼亚和中国农业资源投入、种植业和畜牧业单产水平的历史变化，以及农业资源投入与产量之间的关系，为肯尼亚粮食危机和消灭贫困提供更多的理论支撑。研究结果表明，在20世纪60年代，肯尼亚耕地、草地和降水等自然资源人均占有量比中国高2~3倍，且人均食物能量和蛋白质供应显著高于中国。当前，肯尼亚人均资源拥有量仍高出中国约30%，但是其人均食品供应和粮食自给率却远低于中国平均水平。这是由于与肯尼亚相比，中国在种植业和畜牧业长期持续的投入，大幅度地增加了种植业和畜牧业能量或蛋白质单产水平。1961-2017年，中国和肯尼亚作物蛋白的平均单产分别增加282%和44%。中国的数据表明，种植业和畜牧业单产水平与肥料、精饲料、机械和农药的投入具有显著正相关性；农牧业生产结构对单产水平的变化影响也很大，如种植业中蔬菜和水果播种面积占比，畜牧业中单胃动物饲养占比等。总的来说，农业资源投入和农业结构对生产力的提高都有很大的影响，这可能是肯尼亚提高农业生产力的潜在选择。

Changes in agricultural resource input and productivity in Kenya and China

Both Kenya and China are facing great challenges in feeding their populations; this is particularly problematic in Kenya, where the population will be projected to increase by 1.4 times from 2018 to 2100. Food production has been greatly improved in China, but it still lags behind in Kenya. In this study, we systematically compared the changes in agricultural resources and crop/livestock productivity, as well as their relationships with the resource input levels and agricultural production structure, to try to provide insights into reducing food insecurity and poverty in Kenya. Our results revealed that Kenya had 2-3 times more natural resources, such as cropland, grassland, and annual precipitation, per capita than did China in the 1960s, which was similar to the daily food energy and protein supply. Currently, Kenya still has higher natural resources per capita, but has lower food security and quality when compared to China. This is due to the continued rapid increase in crop and livestock productivity regarding energy and protein production in China. From 1961 to 2017, crop protein productivity increased by 44% in Kenya, while in China it increased by 282%. Our results showed that crop and livestock productivity positively correlated with the input of fertilizers, concentrate feeds, machinery, and pesticides, as seen in China. Meanwhile, the structure of crop and livestock production also showed a large impact on the changes in productivity, such as the harvest area of vegetables/fruits to the total harvest area and the ratio of monogastric animals for livestock production. Overall, both agrochemicals and structure have strong impacts on the increase in productivity, and these could be potential options in Kenya to improve productivity due to the low input of resources into crop and livestock production.