agriculture-pasturage ecotone in Northern China
calcareous soil in Northern China
desert region in northern China
desert regions in northern China
Drought and flood in Northern China
drought in northern China
dryland field in Northern China
farming-grazing zone in northern China
grassland in northern China
Hilly area in northern China
interlock area of farming-pasturing typical region in northern China
cable digital TV networking in cities and counties
children in cities and towns
children of farmers working in cities