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We investigate the determinants of the remarkable increase in intra-regional migrations since the 1980's in Spain, using
a large administrative micro dataset on migrants. Conditional migration probabilities are identified by comparing the migrants'
joint distribution of characteristics to the corresponding distribution from the Spanish Labour Force Survey. The proportion
of employment in the service industry, unemployment, house prices and education, all have an important positive effect on
the individual probabilities of intra-regional migration.
Received: 16 May 1999/Accepted: 26 September 2000 相似文献
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Despite the highly disrupted nature of abandoned industrial sites, they have significant human and ecological value. Ecological recovery at such sites is determined by complex interactions between natural factors and anthropogenic influences. Here we describe the land-use history and ecology of a former industrial wasteland. The spatial and temporal distribution of human disturbance at the study site included early farming, clay mining, brick making and landfilling, activities which have had profound and lasting ecological impacts resulting in a diverse but highly disrupted successional mosaic. Understanding the postdisturbance ecological recovery at this site has required a knowledge of natural factors such as slope, soil types and bedrock geology and hydrology, coupled with a detailed knowledge of the land-use history. Compared to recovery trajectories from many types of natural disturbance, ecological change at this site has been slower and more variable. Understanding ecological history has been crucial in projecting future changes as well as in making wise decisions about use and management practices for the site. 相似文献
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