Suchergebnisse

This book explores recent experiences in the effort to bring about a Green Revolution in Sub-Saharan Africa (SSA). The chapters focus on rice and maize, which are promising and strategic smallholder crops. Significantly, we find that an African Rice Revolution has already begun in many irrigated areas, using Asian-type modern varieties, chemical fertilizer, and improved management practices. Further, we find that the same technological package significantly increases the productivity and profitability of rice farming in rainfed areas as well. We also find evidence that that management training, when done well, can boost productivity on smallholder farms. This suggests that African governments can accelerate the pace of Africa's Rice Revolution by strengthening extension capacity. The story for maize is wholly different, where most farmers use local varieties, apply little chemical fertilizer, and obtain very low yields. However, in the highly populated highlands of Kenya, a number of farmers have adopted high-yielding hybrid maize varieties and chemical fertilizer, as was the case in the Asian Green Revolution, apply manure produced by stall-fed cows, as was the case during the British Agricultural Revolution, and keep improved cows or cross-breeds from European cows and local stock, as was the case of the Indian White Revolution. We conclude that while rice in Africa has benefited from an Asian Green Revolution strategy that emphasizes modern seeds, inputs, and focused knowledge transfers, the success of Africa's Maize Revolution will require a different system approach based on hybrid maize, chemical and organic fertilizers, and stall-fed cross-bred cows

This study examines fuel switching in electricity production following the introduction of the European Union's Emissions Trading System (EU ETS) for greenhouse gas emissions. A short-run restricted cost equation is estimated with carbon permits, high-carbon fuels, and low carbon fuels as variable inputs. Shadow values and substitution elasticities for carbon-free energy resources from nuclear, hydroelectric and renewable sources are imputed from the cost equation. The empirical analysis examines 12 European countries using monthly data on fuel use, prices, and electricity generation during the first phase of the European Emissions Trading System. Despite low emission permit prices, this study finds statistically significant substitution between fossil fuels and carbon free sources of energy for electric power production. Significant substitution between fossil fuels and nuclear energy also was found. Still, while 18 of the 20 substitution elasticities are statistically significant, they are all less than unity, consistent with limited substitution. Overall, these results suggest that prices for carbon emission permits relative to prices for carbon and carbon free sources of energy do matter but that electric power producers have limited operational flexibility in the short-run to satisfy greenhouse gas emission limits.

Spatial disparity in incomes and productivity is apparent across and within countries. Most studies of the determinants of such differences focus on cross-country comparisons or location choice among firms. Less studied are the large differences in agricultural productivity within countries related to concentrations of rural poverty. For policy, understanding the determinants of this geography of agricultural productivity is important, because strategies to reduce poverty often feature components designed to boost regional agricultural incomes. Census and endowment data for Ecuador are used to estimate a model of endogenous technology choice to explain large regional differences in agricultural output and factor productivity. A composite-error estimation technique is used to separate systemic determinants from idiosyncratic differences. Simulations are employed to explore policy avenues. The findings suggest a differentiation between the types of policies that promote growth in agriculture generally and those that are more likely to assist the rural poor.