Household Food Security in Developing Countries: Understanding the Role of Dynamic Natural and Social Systems.

摘要

The lack of consistent and reliable levels of nutritious food may be one of the most brutal results of poverty. Beyond the human suffering, the lack of food security has damaging economic consequences, making it difficult for communities to break poverty cycles. This dissertation studies the various decisions made by households, governments, and the international community that impact household food security. Food security, the long-term availability of nutritious foods, is essentially achieved through a trade-off of consumption and investment in assets and capital to ensure future availability of food.;Chapter 2 builds an optimal control model to analyze the trade-offs between stocks of primary forest and agricultural production. This study highlights the role of ecosystem services provided by stocks of forests, which include protection from flooding and erosion, maintenance of soil quality, and contributions to healthy watersheds. The model developed analyzes food production and consumption decisions in the context of sufficient and consistent access to food, particularly represented by changes in the stock of natural capital, in this case primary forest, which is utilized by the population for various reasons, including being cleared to create room for agriculture production. The case study of forest stocks in Nepal demonstrates the cost reductions achieved in the agriculture sector due to the presence of forest stock. The analysis determines optimal levels of per capita agriculture land for the three geographic belts of Nepal: Terai, Hills, and Mountain regions. Steady states in the model are reached beyond 200 years.;Chapter 3 employees data from a World Food Program household survey carried out in 2005, analyzes the role of natural capital, social capital, coping strategies, and levels of violence in determining household food security levels. Using remotely sensed data of two time points--Thematic Mapper (TM) of 1990 and Enhanced Thematic Mapper (ETM+) of 2000, vegetation information was derived for the uses of mapping of vegetation quality, the study uses two-stage ordinary least squares and non-linear spatial modeling econometric techniques to analyze the data. The results indicate household food security is positively impacted by higher levels of vegetation cover in the village where a household is located, as well as by higher vegetation quality in areas surround the village. Time spent accessing drinking water from improved sources is observed to have a negative relationship with food security. The existence of social networks was seen to positively impact food security, while households identified as members of a lower caste relate negatively with food security. Coping strategies analyzed include remittances received by the household, access to financial credit, and the receipt of food aid. All of these strategies have a positive impact on the level of household food security. The intensity of violence in the village and surrounding areas throughout the Maoist conflict is observed to have a negative impact on household food security.;Chapter 4 undertakes a dynamic panel analysis of the worldwide distribution of emergency food aid in response to natural disasters and the displacement of citizens due to conflict. This is important, as exogenous shocks have the potential to derail the optimal consumption and investment decisions made by households aiming to ensure long-term food security. The data comes from the United Nations WFP Food Aid Information System (FAIS), which aims to provide reliable crosschecked data on all food aid transactions by countries and NGOs, whether or not the food aid was distributed by WFP. The analysis uses a Generalized Method of Moments system approach, which allows a control of the dynamic nature of the data, as well as potential endogeneity issues. As in previous studies, we show a significant relationship between rapid onset disasters (e.g. floods, hurricanes, and earthquakes) and the international response of food aid. Unique to this study, we demonstrate a lag effect of aid in response to gradual onset disasters (droughts, extreme temperature, and disease). This is a particularly important response when considering the potential for increased gradual onset natural disasters in response to climate change. We also show a highly significant and positive relationship between emergency food aid and displaced people. (Abstract shortened by UMI.)