In the case of SSA there remains a heavy reliance on human power and, in some locations, draft animal power. The HIV/AIDS pandemic combined with urban migration is reducing the labor available to rural households;

• 撒哈拉沙漠以南的非洲地区仍然对人力甚至畜力存在很大依赖。大范围HIV/AIDS感染，以及农村人口向城市的迁徙，降低了农村家庭劳动力的利用率。