This study intended to consider the sustainability of irrigation fruit farming in terms of water supply-demand situation from the viewpoint of tolerance to drought events in Petrolina and its surrounding area in Brazil, where large-scale irrigation projects have been developed for semi-arid regions. Based on the field survey, we analyzed the actual situations of water intake and distribution on the water supply side and irrigation agriculture on the water demand side. The decrease in water resources in this region in recent years has been dramatic. However, this study revealed that the irrigation fruit farming in this region has managed to sustain itself without decreasing the area of cultivation and the harvest of produce even under the water shortage scenario of recent years. The biggest reason for this is the introduction of water-saving irrigation systems in this region in the late 1980s and the spread of these systems among most of the farmers in the region today. Meanwhile, there is also another issue unique to the region; the electricity cost has soared in the event of drought because the region relies on obtaining most of its electricity from hydroelectric power generation. It can be said that irrigation fruit farming in this region carries the dual risk of irrigation water shortage: the direct risk of irrigation water shortage due to recent continuing water scarcity and the indirect risk of insufficient irrigation water due to the restriction of irrigation facility operation with electricity shortage and soaring electricity costs caused by the shortage of power generation water.

Socio-economic residential segregation is an important issue of social concern and academic interest. Using population census data, we analyze the changes in residential segregation by finer occupational groups at the neighborhood level and their local spatial distribution in Tokyo from 1980 to 2005. This period was characterized by increasing economic disparities in Japan. We find that: 1) Multiple segregation indices provide evidence of some level of residential segregation by occupational groups at the neighborhood level in Tokyo. The level of residential segregation is higher for both ends of the occupational hierarchy than it is for other occupational groups. 2) While the overall level of residential segregation has continually declined, this does not necessarily translate into desegregation between opposite social groups. Furthermore, there are different patterns of changes in residential segregation, even between white- and gray-collar workers. Therefore, using finer or larger occupational groups leads to different insights on the changes in socio-spatial segregation. For the highest occupational group (managerial workers), the level of residential segregation from the lowest group was growing. However, segregation also increased from other occupational groups, except for a short period immediately following the collapse of the bubble economy in the early 1990s. Managerial workers were even more spatially concentrated in central areas of Tokyo, which were already highly concentrated.

This paper aims to explain the mechanism of the transfer of farming rights in Japan’s large-scale upland farming belt by focusing on the social relationships among farmers. The mechanisms of farmers’ social relationships were analyzed by applying the concept of “multiplex-uniplex” that is used in the social network approach. The study area was Omaki and Kowa settlements in central Hokkaido Prefecture. This area was newly cleared and opened for settlement in 1950. The major agricultural enterprises in this area are upland, dairy, and vegetable farming. The main findings are as follows. 1) Various social relationships among farmers were observed behind the transfer of farming rights, including territorial relations, kinship and school connections. Some official agencies were also involved in these relationships. 2) The types of social relationships varied in the way the transfer of farming rights overlapped. Almost all transfers were influenced by multiplex relationships, such as a combination of territorial relations, kinship, and school connections. On the other hand, uniplex relationships existed in the transfer of farming rights when farmers did not have these social relationships. 3) Social relationships in the transfer of farming rights expanded spatially from the scale of the neighborhood or settlement to the scale of the home district, other districts, and outside of town. Many farmers accumulated most of their farmland within their settlements, but depending on farm management conditions, some late accumulated farmland was located outside their settlements.