In Asia, the productivity gain attributable to high land quality is 34 percent. In Latin America, where most countries lie above the global median in terms of land quality, only the best soils and climate are significantly associated with increased agricultural productivity. Conventional inputs and other factors Land quality also affects the impact on agricultural productivity of more conventional inputs, such as quantities of land, labor, and fertilizer. In sub-Saharan African countries with good soils and climate, agricultural land productivity rises significantly with increases in labor, livestock, tractors, fertilizer, and annual rainfall. In sub-Saharan African countries with poor soils and climate, productivity responds even more strongly to fertilizer application, irrigation, and political instability, but is not sensitive to improvements in tractors, labor quality, or infrastructure.
Similar patterns characterize other developing regions.
In Latin America, increases in labor, fertilizer, and irrigation are associated with increased productivity of agricultural land in countries with poor soils and climate, but not in countries with good soils and climate. Improvements in literacy and transportation infrastructure are associated with increased productivity in countries with good soils and climate, but not in those that are poorly endowed. In Asia, additional land, labor, and roads increase agricultural productivity in countries with good soils and climate, but not in those that are poorly endowed, where productivity is relatively more sensitive to increased irrigation. Land degradation Analysis of differences in land quality across countries and regions also provides an initial indication of the potential impact on agricultural productivity of changes in land quality, such as land degradation, over time. Nevertheless, in some areas characterized by poor or fragile soils and inappropriate agricultural management practices, productivity losses could be significantly higher.