Subsistence agriculture

About: Subsistence agriculture is a research topic. Over the lifetime, 8069 publications have been published within this topic receiving 156876 citations. The topic is also known as: subsistence farming.

Human Ecology in Savanna Environments

Abstract: Like most terms for vegetation types, savanna has a variety of definitions, but David R. Harris, the editor of this series of papers, presents a new (at least to this reviewer) perspective. He includes all tropical areas with 2.5-7.5 dry months, which he believes embraces everything between tropical rain forest and desert. According to him, this "savanna" or "Intermediate Tropical Zone" has a "continuous herbaceous layer dominated by bunch grasses" throughout. And indeed, his diagram of evergreen seasonal forest indicates such a ground layer, although this is certainly not true of undisturbed seasonal forest, deciduous or evergreen, in MesoAmerica or northern South America. This terminologic ineptness aside, Harris points out that there is good reason for treating the indicated ecosystem catena as a unit, at least in historic human ecology, for early man seems to have avoided both desert and rain forest. Furthermore, archeologic sites cannot be equated with definite vegetation types with precision, and indeed the environment at any one site has undoubtedly shifted back and forth repeatedly. The book is divided into three Parts. Part I contains nine contributions concerning the development of human cultures in various parts of the dry tropics. Separate authors deal with Latin America, Africa, Australia, India, Indonesia, and Melanesia. In view of the broad definition of savanna, which includes approximately a quarter of the earth's land surface, and the many-faceted nature of human ecology, the ecosystems that have been studied are as varied as the perspectives of the different workers. For example, J. Desmond Clark shows how prehistoric climatic oscillations and the natural resources available have shaped modern land use in arid Africa. Philip Burnham's paper on East Africa emphasizes modern social organization and problems rather than prehistory, and Georges Condominas describes the pre-war ritualridden life style of aborigines practicing swidden agriculture in the dipterocarp forests of Vietnam. In this part Jacques Barrau points out that in Melanesia land use changes initiated by Europeans have proven less energyefficient than the primitive type, so he recommends a reevaluation of primitive life styles there. In contrast, James Parsons finds that modern technology promises to reverse the economic deterioration of arid Venezuela and Colombia that set in as cattle ranching developed. Part II starts out with four articles on the basic ecology of native plant and animal life. P.A. Jewell calculates that in arid Africa each family that depends on cattle for existence requires a minimal herd of about 44 cattle and 100 goats, with about 100 ha of range land at its disposal. If giraffe management were integrated with the cattle, production would be materially increased, for giraffe can yield 125 kg meat/km2/yr without offering any competition to the cattle. Part III is devoted to the human biology of tropical dry lands. The physiologic work capacity of African men proves to be lower than that of European men in consequence of the larger muscles of the better nourished Europeans. Toward the end of the dry season food usually becomes scarce, yet field work must continue, and in consequence the energy intake falls below needs at times. In Africa the abundant large game has been a major food source throughout man's evolution, leading to his ultimate heavy dependence on domestic livestock. By contrast, the paucity of large game in the arid parts of the American tropics resulted in developing a dependence on crop plants for food. Erica Wheeler states that protein requirements for good nutrition have been overstated, with fat requirements under-estimated. Dietary variety usually decreases as the hunter-gatherer life style gives way to that of a farmer, then may decline further with change from subsistence to cash-crop farming. Physiologic research has shown that heat acclimatization rises to a very high state only where high pay provides a strong work incentive. Aridity forces people to live near water supplies in the arid regions, and the major infectious diseases of the tropics are water-associated. In contrast with the effects of malarial and hookworm infections, schistosomiasis does not decrease the work output of Africans. Although the content of the individual contributions is substantial, the interests of the workers and the diversity of the cultures studied are so varied that one can expect very little continuity in the book as a whole. Rather, one is impressed by the complexity of human ecology in the dry tropics, as well as the ineptness of the developmental attempts thus far. The volume has a general index, with a separate index of place-names. Each contribution includes a list of references. Illustrations other than maps are minimal, as is tabular material.

Producing more food with less water in a changing world: assessment of water productivity in 10 major river basins

Abstract: This article summarizes the results of water productivity assessment in 10 river basins across Asia, Africa and South America, representing a range of agro-climatic and socio-economic conditions. Intensive farming in the Asian basins gives much greater agricultural outputs and higher water productivity. Largely subsistence agriculture in Africa has significantly lower water productivity. There is very high intra-basin variability, which is attributed mainly to lack of inputs, and poor water and crop management. Closing gaps between “bright spots” and the poorly performing areas are the major tasks for better food security and improved livelihoods, which have to be balanced with environmental sustainability.

Plagues, Wages, and Economic Change in the Islamic Middle East, 700–1500

Abstract: This study establishes long-term trends in the purchasing power of the wages of unskilled workers and develops estimates for GDP per capita for medieval Egypt and Iraq. Wages were heavily influenced by two long-lasting demographic shocks, the Justinian Plague and the Black Death and the slow population recovery that followed. As a result, they remained above the subsistence minimum for most of the medieval era. We also argue that the environment of high wages that emerged after the Justinian Plague contributed to the Golden Age of Islam by creating demand for higher income goods.

Food expenditures and household demographic composition in the US: A demand systems approach

Abstract: Food expenditures and subsistence quantities of poverty status and non–poverty status US households are analysed within a Linear Expenditure System that postulates subsistence quantities to be linear combinations of demographic variables. Using the US Bureau of Labor Statistics' 1992 Consumer Expenditure Survey and Detailed Monthly Consumer Price Indices, this article obtains expenditure elasticities, own–price elasticities and subsistence quantities for each income group across nine broadly aggregated food commodity groups. Elasticity estimates and subsistence quantity estimates differ across income groups, supporting the premise that policies targeted at specific income groups should be based on the target group's elasticity estimates rather than average population elasticities. Parameter estimates are then used to simulate how subsistence quantities and own–price elasticities can be expected to vary according to the demographic composition of the household within a specific income group.

International Migration, Remittances and Subsistence Farming: Evidence from Nepal

Abstract: Although international migration is playing an increasingly important role in Nepal, at both the macro and household levels, and in particular for the poverty reduction of rural families, empirical work focusing on this phenomenon has been largely absent With a special view on the rural poor, in this paper we investigate the impact of international labour migration on subsistence agricultural production in the Western Mid Hills of Nepal, based on a survey conducted among smallholders with migrating family members The results demonstrate that international migration leads to negligence of cereals – paddy, wheat, maize and millet, in particular, being the major subsistence crops While bearing a negative impact on family labour input, its impact on hired farm labour is positive Yet it does not affect material inputs such as fertilizer, and although it helps to ease households’ liquidity and capital constraints, it does not contribute to moving subsistence farming towards more profitable commercial farming Therefore, although migration reduces poverty in the short run and also allows for higher daily consumption, its negative impact on cereal production requires attention by policymakers