Regional Population Stress and Internal Migration in Mexico.

Abstract

A model explaining net migration in Mexico in terms of population retention capacity of the rural and urban sectors is presented. The migration model is based on the concept of population stress defined as the pressure of surplus population on the resources after the optimum population is absorbed. Population stress involves carrying capacity and population pressure. Carrying capacity is a theoretical optimum population that a district can support at acceptable st and ard. The measure is relative to potential income open to migrants in Mexico City. Population pressure is a measure of actual number of people supported by a unit resource of a given area and out migration is directly related to population stress. The model is tested at two scales, at the national level with states as observations and at the state level with municipios as observations. Michoacan and Sonora were selected for the state level analysis since they are representative cases of the dual nature of the agricultural sector of Mexico. The result of the analysis at the state level indicate a significant negative relationship between the population stress of the rural sector and percent net migration. For the municipio level analysis, a simplified version of the model was used because of the data unavailability. The rural population stress alone explained 35 percent of the net migration in Sonora, and 14 percent of the variation in the case of Michoacan. The proximity of attractive job opportunities nearby in the commercial farms of the Sonoran desert, and maquila industries in Nogales along the border with the U.S. may make the population in Sonora more willing and able to move than inhabitants of Michoacan.