Method Of Grid Reconstruction Of Historical Population Pattern

"Person",as the core of the earth environment system,is the main driving factor of land use/cover and global change.Spatial distribution of population is the aggregation state of population in the region within a certain period of time,which is a form of population change in space.As the study on environmental change and sustainable development deepen,the positive effects of people as the basic input data aided in studies of disaster risk assessment and rescue,city infrastructure and public service facilities,health science and climate change impact assessment obtain more importance by geography,demography,sociology and other disciplines.However,the statistic population acquired by statistics,census and summary with traditional administrative divisions as the basic unit has not been able to meet the requirements of social development.With the rapid development of RS and GIS technology,the research on population spatialization provides a feasible approach for the above problems.The emerging and promoting of researches on spatial distribution of population in historical period are based on the background of understanding population development,exploring long period of population-environment response mechanism and monitoring or testing historical LUCC.Limited to the complexity of distribution mechanism of population spatialization ii the historical period and the difficulty of historical data acquisition,research on the spatial pattern of population recovery in historical period is still blank at present.In view of this,this study attempts to construct a set of historical population pattern grid method to achieve high accuracy allocation of the population of historical period to provide basic data for population-environment response mechanism research and historical land use/landcover reconstruction,and takes an example to test the effectiveness of the model,thus providing the experience and methods reference for carrying out a larger,longer regional history population spatialization.The main conclusions of this study are as follows:(1)Land use is the spatial direction of population distribution in historical period.City population live and have handicraft production and commodity trading activities within the city space,while the rural population take the rural settlement as the place of residence,take the cultivated land surrounding the settlement as the working place for agricultural production activities.Within the space range of the directivity factors,population distributioin is influenced by the gravity of town center,road infrastructure,natural environment,occasional events(including government behavior,wars and natural disasters),and with the continuous development of the commodity economy in historical period,the impact of urban center attraction gradually increases(2)The study breaks through traditional method of allocation of population space,and takes land use as the space boundaries of allocation of urban and rural population.In addition to considering natural environment,infrastructure and other factors which affect population distribution,this study takes towns as the center,considering the important effects which central function of towns by the form of social economy generates to population distribution,thus building history population gridding method of population distribution of activity type within residential space.The method embodies certain innovation.(3)Considering the serious and critical contradiction between land and population of Suzhou in Mid-Qing Dynasty,this research chooses Suzhou as the typical reconstruction area and 1776Y and 1820Y in Mid-Qing Dynasty as the typical period.This research confirms spatial range of all directivity factors and finishes population recovery through studying local chronicles,literature and existing research results.Meanwhile,according to the population configuration rules,this researchrealizes population reconstruction(1km× 1km grid)of two typical periods.(4)It confirms the validity of model by contrasting the reconstruction results with population data in chronicles and modern population relevance.In comparison to data in chronicles,when the average population density of rural residential areas is 8 times to the average population density of areas which are removed residential area(Z=8),the mean error rate is minimum and the reconstruction precision is the highest.The study finds that the relative error of Wuchangyuan,Changzhao,Wuzhen and Kunxin is-5.2%,15.7%,3.2%and 16.6%.Strong correlation between reconstruction population and modern population in two typical periods is verified,and population distribution and its changes keep consistency.In general,reconstruction results are credible.The model has high simulation precision and parameters used for modeling are reasonable.