Africa's changing farm size distribution patterns : the rise of medium-scale farms

This study assesses changes over the past decade in the farm size distributions of Ghana, Kenya, Tanzania, and Zambia, drawing on two or more waves of nationally representative population-based and/or area-based surveys. Analysis indicates that much of Sub-Saharan Africa is experiencing major changes in farm land ownership patterns. Among all farms below 100 hectares in size, the share of land on small-scale holdings under five hectares has declined except in Kenya. Medium-scale farms (defined here as farm holdings between 5 and 100 hectares) account for a rising share of total farmland, especially in the 10–100 hectare range where the number of these farms is growing especially rapidly. Medium-scale farms control roughly 20% of total farmland in Kenya, 32% in Ghana, 39% in Tanzania, and over 50% in Zambia. The numbers of such farms are also growing very rapidly, except in Kenya. We also conducted detailed life history surveys of medium-scale farmers in each of these four countries and found that the rapid rise of medium-scale holdings in most cases reflects increased interest in land by urban-based professionals or influential rural people. About half of these farmers obtained their land later in life, financed by nonfarm income. The rise of medium-scale farms is affecting the region in diverse ways that are difficult to generalize. Many such farms are a source of dynamism, technical change, and commercialization of African agriculture. However, medium-scale land acquisitions may exacerbate land scarcity in rural areas and constrain the rate of growth in the number of small-scale farm holdings. Medium-scale farmers tend to dominate farm lobby groups and influence agricultural policies and public expenditures to agriculture in their favor. Nationally representative Demographic and Health Survey (DHS) data from six countries (Ghana, Kenya, Malawi, Rwanda, Tanzania, and Zambia) show that urban households own 5–35% of total agricultural land and that this share is rising in all countries where DHS surveys were repeated. This suggests a new and hitherto unrecognized channel by which medium-scale farmers may be altering the strength and location of agricultural growth and employment multipliers between rural and urban areas. Given current trends, medium-scale farms are likely to soon become the dominant scale of farming in many African countries.This study was presented at the 29th Triennial International Conference of Agricultural Economists, August 13, 2015, Milan, Italy.The Bill and Melinda Gates Foundation through the Guiding Investments in Sustainable Agricultural Intensification in Africa (GISAIA) grant at Michigan State University, and from the Food Security Policy Innovation Lab, funded by USAID's Bureau for Food Security.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1574-08622018-11-30Agricultural Economics, Extension and Rural Developmen

Explaining permanent and temporary water market trade patterns within local areas in the southern Murray–Darling Basin

The southern Murray–Darling Basin of Australia has the world’s largest and most sophisticated water markets. However, there has been little study on the drivers of permanent and temporary water market movements within local areas, or the substitution effects between groundwater and surface-water extraction over time. This topic is important as it is often claimed that water market trade patterns (especially selling large amounts of permanent water) are associated with rural decline. This study uses random-effects tobit panel models to investigate the association of regional and spatial socio-economic characteristics with temporary and permanent southern Murray–Darling Basin water market trade, using a broker panel database at postcode level from 2010/11 to 2013/14. Overall, results suggest there is no statistical significant evidence that more disadvantaged communities sold larger amounts of permanent water. Permanent water selling was statistically more likely to be associated with other spatial and land productivity characteristics, while temporary water market trade volumes were more related to water scarcity factors. In addition, there was evidence to suggest a substitution effect between rural areas selling higher volumes of permanent water and using higher volumes of groundwater.Juliane Haensch, Sarah Ann Wheeler, Alec Zu

Computational modeling of city formation

Although a burst of recent research in economics has examined how industries form, a majority of it considers highly simplified models. In this paper, we use computational modeling techniques to expand from traditional, simple, analytically tractable economic models to more complex two dimensional landscapes. Using the basic theories developed in earlier research, we examine what factors cause cities to emerge, including: transportation costs, the percentage of workers in a population, and the elasticity of substitution. These three factors should cause workers and firms to agglomerate, causing cities to emerge out of a scattered population. Copyright Springer Science+Business Media, LLC 2007Computational modeling, City formation, Evolutionary algorithms,