Research on Spatio-Temporal Differentiation Characteristics of the Construction Level of Green and Plaza Land in China

Green and plaza land(GPL) is one of the basic elements of urban construction, and is also the most basic public space to meet the needs of citizens for a better life. The exploration on its internal development laws can provide theoretical foundations for the planning of GPL and creating good human settlements. Taking 612 cities in China as the study area and from the "people-land" perspective, this paper selects the total GPL area, the per capita GPL area, and the land use proportion of per capita GPL as indicators to analyze the spatio-temporal differentiation characteristics and evolution rules of the construction level of GPL in China from 1996 to 2016, by using mathematical statistics and spatial analysis methods. The result shows:(1) from a national perspective, the construction level of GPL in China has been rapidly improved along with the temporal evolution, but there is still a big gap from the upper limit of the standard. In terms of the spatial distribution, regional differences have always been great, and the cities scoring below the standard are concentrated in the eastern and central regions, while high-scoring cities are more concentrated in the western region; the distribution of the land use proportion of per capita GPL is in a pattern that the eastern region has the highest proportion, followed by the western region, central region, and northeastern region successively.(2) From the perspective of scale, differences between cities of different sizes exist over a long period of time, and there is an obvious imbalance in the per capita GPL area as well as the land use proportion of per capita GPL between different cities. The construction level shows that small cities have the highest level, followed by medium-sized cities and then large cities.