Regional Characteristics Of Human Migration Dynamics

Set in population migration in rural areas,a discrete dynamical model described by a map is established to study the regional characteristics of the population distribution caused by the migration.Population migration driven by interests often takes place as the result of interaction of some related factors.A model describing population migration between regions is proposed based on a so-called generalized potential function.The dynamic rules are:when the generalized potential for a given region is higher than the average over all of the regions,some people would like to migrate out of this region;the regions that their generalized potentials are of lower than the average will become the migration destinations,immigration regions,for the upcoming migrating people;the allocation of such upcoming migrating people to the immigration regions is determined by difference of the generalized potentials between the given region and the corresponding immigration regions.The calculated results show some regulations that govern the migrating process:the number of migration people in a region,neither immigration or emigration,decays generally in an exponential way with time,which leads to the amount of people,income per capita and public service resources per capita in the emigration/immigration region decreases/increases in an exponential/"anti-exponential" way,and finally reach a relative steady state at which the mentioned three key factors match each other.The variation of information entropy and the evolution of pattern-formation for the regions indicate that the system evolves towards order in the progress of polarization of population distribution.The urban population can in fact be divided into floating population and resident population.The floating population is mainly from the rural areas,and is an important part of urban labor force.Considering the transformation of labor force status between the floating and the resident in the central urban and the migration between the rural areas and the central urban,and based on the theories of statistical dynamics,a continuous dynamics model for population migration described by a set of differential equations is suggested to investigate the basic characteristics of population migration between the central urban and rural areas.The simulation results show that the migration leads the rural areas to forming three types,net emigration,net immigration,first emigration then immigration.It is necessary to point out that the second central urban,of which the population scale is close to the first located at the origin of coordinate,emerges in one of the first emigration then immigration areas.By analyzing the population density changes in the moved back areas-net immigration and first emigration then immigration areas,the regularities dominating evolution of the floating population and resident population in the first central urban and that in the rural areas is revealed.It may provide explanation for what caused the emergence of the second central urban.The empirical results illustrate the realistic correspondence of the simulation results.