100-m resolution Age-Stratified Population Estimation from the 2020 China Census by Township (ASPECT)

<b>Introduction</b>: Gridded population datasets are instrumental for modeling the interactions between human and the environment at fine spatial scales. Here, we introduce an Age-Stratified Population Estimation from the 2020 China Census by Township (ASPECT), estimating total population and population by age groups (0-14, 15-59, 60-64, ≥65 years old) at 100m spatial resolution as of year 2020. We used a dasymetric mapping approach to downscale township-level population data (n=40,718 townships) from the 2020 China Census to 100 by 100 m grid cells. The study area is <b>mainland China</b>.<b>Data records</b>: ASPECT includes GEOTIFF files on <b>population dens</b><b>ity</b><b> (persons per hectare) </b>at 100 m spatial resolution. No data areas indicate townships missing the 2020 Census data (n=590) and areas fall outside our study area, mainland China. The files are:population_total_pop: gridded estimates on total populationpopulation_age0_14: gridded estimates on population between 0 and 14 years oldpopulation_age15_59: gridded estimates on population between 15 and 59 years oldpopulation_age60_64: gridded estimates on population between 60 and 64 years oldpopulation_age65above: gridded estimates on population ≥65 years oldpopulation_total_pop_sum: gridded estimates on total population, summed with age-group specific estimates (file 2-5). This file is used to calculate the proportion of each age group.ASPECT also includes GEOTIFF files on <b>the proportion (%) of population by age groups</b> at 100 m spatial resolution. No data areas indicate townships missing the 2020 Census data, places fell outside our study area, and places with zero population. Proportion of a population age group is calculated by dividing its population counts by the sum of population from all age groups (i.e., grid cell values from the “population_total_pop_sum.zip” file). The files are:proportion_age0_14: the proportion of population between 0 and 14 years oldproportion_age15_59: the proportion of population between 15 and 59 years oldproportion_age60_64: the proportion of population between 60 and 64 years oldproportion_age65above: the proportion of population ≥65 years oldAll GEOTIFF files are projected with WGS 1984 geographic coordinate system (EPSG: 4326). The files are compressed in zip format. Once uncompressed, the GEOTIFF files can processed by GIS software such as ArcGIS, and by programing language packages such as Rasterio in Python.<b>Reference</b>: 100-m resolution Age-Stratified Population Estimation from the 2020 China Census by Township (ASPECT), published by Scientific Data [link]<b>Citation</b>: Ju, Y., Liang, Y., Kong, J., Wang, X., Wen, S., Shang, H., &amp; Wang, X. (2025). 100-m resolution Age-Stratified Population Estimation from the 2020 China Census by Township (ASPECT). <i>Scientific Data</i>, <i>12</i>(1), 1058. https://doi.org/10.1038/s41597-025-05401-1

**引言**：格网人口数据集是在精细空间尺度上模拟人类与环境交互作用的核心工具。本研究推出基于2020年中国乡镇人口普查的年龄分层人口估算数据集（Age-Stratified Population Estimation from the 2020 China Census by Township，简称ASPECT），该数据集以2020年为基准，以100米空间分辨率估算了总人口及分年龄组（0-14岁、15-59岁、60-64岁、≥65岁）的人口数量。我们采用密度分区制图法（dasymetric mapping），将2020年中国人口普查中的乡镇级人口数据（共40718个乡镇）降尺度至100×100米的格网单元。研究范围为中国大陆地区。

**数据记录**：ASPECT包含100米空间分辨率下的人口密度（单位：人/公顷）GEOTIFF格式文件。无数据区域对应两类：一是缺失2020年人口普查数据的乡镇（共590个），二是研究范围之外的区域。具体文件如下：
- population_total_pop：总人口格网估算结果
- population_age0_14：0-14岁人口格网估算结果
- population_age15_59：15-59岁人口格网估算结果
- population_age60_64：60-64岁人口格网估算结果
- population_age65above：≥65岁人口格网估算结果
- population_total_pop_sum：总人口格网估算结果，由各年龄组（即上述第2至5个文件）的人口数求和得到，该文件用于计算各年龄组的人口占比。

ASPECT还包含100米空间分辨率下的分年龄组人口占比（单位：%）GEOTIFF格式文件。无数据区域包括：缺失2020年人口普查数据的乡镇、研究范围之外的区域以及人口为零的区域。某一年龄组的人口占比通过将该年龄组的人口数除以所有年龄组的人口总和（即population_total_pop_sum.zip文件的格网单元值）计算得到。具体文件如下：
- proportion_age0_14：0-14岁人口占比
- proportion_age15_59：15-59岁人口占比
- proportion_age60_64：60-64岁人口占比
- proportion_age65above：≥65岁人口占比

所有GEOTIFF格式文件均采用WGS 1984地理坐标系（EPSG: 4326）进行投影。所有文件均以ZIP格式压缩，解压后可通过ArcGIS等GIS软件以及Python的Rasterio等编程语言包进行处理。

**参考文献**：100米分辨率年龄分层人口估算数据集（ASPECT），发表于《科学数据》[链接]

**引用格式**：Ju, Y., Liang, Y., Kong, J., Wang, X., Wen, S., Shang, H., & Wang, X. (2025). 基于2020年中国乡镇人口普查的100米分辨率年龄分层人口估算数据集（ASPECT）. 《科学数据》, 12(1), 1058. https://doi.org/10.1038/s41597-025-05401-1