This dissertation studies agricultural input intensification, defined as the increased use of modern inputs such as hybrid seeds, mineral fertilizer, herbicide, and pesticide in African agriculture. It also analyses the potential of this intensification to accelerate productivity growth and tests the effectiveness of two policies, input subsidies and land reforms, in promoting it and consequently in increasing crop yield. In the first essay, we argue that to create the conditions for the emergence of a green revolution in Africa, modern agricultural technologies have to be adopted as a package, not in a piecemeal fashion. This argument is consistent with a conceptual framework that we develop to illustrate the importance of harnessing strategic complementarities among agricultural technologies by adopting them simultaneously rather than sequentially. Based on this framework, we propose a methodology to estimate an index to measure agricultural input intensification in its many dimensions. The index provides a simple and intuitive measure to quantify joint adoption of several inputs and compare it across plots, crops, farmers, and regions. Applying this methodology to maize producers in Burkina Faso and Tanzania, we show that our estimated index is a valid measure of joint input adoption and effectively captures the relative importance of each input as well as the number of different inputs adopted. Using the estimated index, we find that simultaneous adoption of modern inputs in Burkina Faso and Tanzania is limited but not rare. Most importantly, we find that the impact of the adoption of individual modern input on yield is increasing with the level of intensification for others. In the subsequent two essays, we assess the effectiveness of government’s direct intervention through input subsidies and indirect intervention through land reforms in promoting agricultural input intensification and increasing productivity. Our empirical analyses focus on Burkina Faso, a country that has recently implemented a fertilizer subsidy program and is undertaking profound land reforms to improve land tenure security and land transferability among households. The second essay tests the hypothesis that subsidizing only one input might promote or discourage the use of other inputs. We find that fertilizer subsidy for maize farmers in Burkina Faso crowds in the use of hybrid seeds and crop protection chemicals, but discourages the use of manure. The last essay assesses whether the development of rural land rental markets can facilitate land transferability among farmers and increase input intensification and productivity. The findings suggest that land rental transfers land from less talented or committed farmers to the more able but have minimal impact on input intensification. However, our results show that land renters are more productive and better farm managers. These results suggest that the short-term gains from policies that foster the development of land rental markets in Burkina Faso, and more generally Africa, will likely be in term of efficiency rather than widespread adoption of modern agricultural technologies.

京都大学 / 新制・課程博士 / 博士(農学) / 甲第24684号 / 農博第2567号 / 新制||農||1101(附属図書館) / 学位論文||R5||N5465(農学部図書室) / 京都大学大学院農学研究科生物資源経済学専攻 / (主査)教授 伊藤 順一, 教授 浅見 淳之, 教授 松下 秀介 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(地域研究) / 甲第21904号 / 地博第250号 / 新制||地||92(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科グローバル地域研究専攻 / (主査)教授 河野 泰之, 教授 藤倉 達郎, 教授 藤田 幸一, 教授 竹田 晋也 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

[pt] Sobretudo nos últimos anos, o Brasil tem intensificado as políticas de reforma agrária e combate à pobreza rural. No entanto, o debate sobre o tema tem ignorado questões importantes relacionadas à origem da concentração fundiária e à eficácia dos instrumentos adotados. A tese tem como objetivo analisar o papel de políticas públicas voltadas ao mercado de terras, considerando um critério de eficiência agrícola, em um ambiente em que (i) as pessoas adquirem terra não apenas para a produção agrícola, mas também para outras finalidades, e (ii) o mercado de arrendamento de terras não funciona adequadamente. Mostra- se que essas duas características não apenas afetam a eficiência da alocação de recursos destinados à agricultura como também têm importantes conseqüências para o desenho de políticas públicas. O capítulo 1 apresenta um modelo teórico que estabelece os princípios básicos da análise sistemática das imperfeições do mercado de terras brasileiro e suas conseqüências para a política econômica. Os capítulos 2 a 4 discutem, respectivamente, aspectos de implementação do programa de reforma agrária redistributiva, da taxação de terras e questões associadas ao mercado de arrendamento de terras. Por fim, a conclusão resume os principais resultados encontrados, as limitações e a pesquisa futura. / [en] In the last few years, the Brazilian government has been intensifying economic policies of land reform and poverty alleviation. However, the debate about this issue has been overlooking important questions related to the land concentration and the effectiveness of the policy instruments. The aim of the dissertation is to analyze the role of such policies in an environment in which (i) land property provides non-agricultural benefits and (ii) the land rental market does not work well. The results indicate that these two characteristics not only ffect the agricultural efficiency but also the design of development policies. Chapter 1 presents a theoretical model establishing the main framework of the analysis, considering market imperfections and their consequences to the land policies. Chapters 2 to 4 discuss some issues of the implementation of three policy instruments - the land reform program, the land tax and the land rental market. The conclusion summarizes the main results of the dissertation, some limitations and the guidelines for future research.

The history of now-developed countries implies a common transformation path of economic development. That is, within an economy, as wage grows in non-farm sectors, labour migrates out of agriculture. With fewer workers, agricultural land resources may concentrate into the hands of fewer but larger farm operations (agricultural land consolidation), with more investment and higher production specification. However, the development process of China is less likely to trace the same path as it does in these countries, given its distinctive institutions. To examine the development process in the unique context of China, this dissertation focuses on two questions: (1) how do China’s rural workers self-select into off-farm employment (OFE)? (2) How does agricultural land consolidation occur in China? In addressing the first question, I use Roy’s self-section model to analyze the following three occupational choices of China’s rural residents: farming only, local OFE, and migratory OFE. Based on household survey data from 101 communities in rural China in 2004 and 2007, the empirical results show that individual and household characteristics are important self-selecting factors for OFE participation. More importantly, I find that the increase of OFE in China is largely consistent with market-driven expectations. In addressing the question of whether and why the consolidation of farm operations develops in China’s agriculture, I assess the divergence between the size of farm operations from equal entitlements. The theoretical model predicts that a higher opportunity cost of farm labour, in the form of the urban wage, exerts a positive influence on consolidation of farm operations through rental arrangements. A Gini index is used to measure the inequality of farmland operations relative to equal farmland entitlements, with greater inequality being consist with higher consolidation of farm operations. Empirical results support the theoretical prediction, specifically, a 1000-yuan increase in the annual urban wage, holding all other influences constant, increases the Gini index by 0.012 (mean=0.26) over the 2004-2007 period.