2000—2020年西安市市辖区城区扩张的时空特征分析

Analysis of the Temporal And Spatial Characteristics of Urban Expansion in Xi′an Municipal Districts from 2000 to 2020

以西安市市辖区为研究对象,借助多时相遥感影像数据,提取西安市市辖区2000、2005、2010、2015和2020 5期城区范围,选取扩展速度、扩展强度、紧凑度、分形维数和弹性系数等扩张指标,结合重心和八方向扩张模型,揭示西安市市辖区近20年城区扩张的时空特征和规律。结果表明:西安市市辖区城区面积2020年是2000年的3.5倍,而人口数2020年是2000年的1.5倍,人地关系不协调;西安市市辖区的城市形态沿“西南—东北”呈梭形分布,城市形态复杂,但随着20年来的不断填补扩张,逐渐趋于规则;近20年西安市市辖区的重心向东南方向移动了约2 km,东北、正北和西南方向的扩张最为突出,西北和东南方向扩张受限。对西安市近20年市辖区的扩张情况进行研究,分析其扩张的时空特征和合理性,可为日后西安市城区规划提供指导和建议,促进城市的持续健康发展。

This paper takes Xi′an′s municipal districts as the research objects and uses multi-temporal remote sensing image data to extract the five-phase urban area of Xi′an′s municipal district in 2000, 2005, 2010, 2015 and 2020, and selects the expansion speed, expansion intensity, and compactness, fractal dimension and elasticity coefficient and other expansion indicators, combined with the center of gravity and eight-direction expansion model, which reveals the temporal and spatial characteristics and laws of urban expansion in Xi’an municipal districts in the past 20 years. The results show that the urban area of Xi′an′s municipal district in 2020 will be 3.5 times that of 2000, while the population in 2020 will be 1.5 times that of 2000. The relationship between human and land is not coordinated. With fusiform distribution and complex urban morphology, but with continuous filling and expansion in the past 20 years, it has gradually become more regular;In the past 20 years, the center of gravity of Xi′an municipal district has moved about 2 kilometers to the southeast, and the expansion in the northeast, true north, and southwest direction is the most prominent, with limited expansion in the northwest and southeast. By studying the expansion of Xi’an municipal districts in the past 20 years, analyzing the temporal and spatial characteristics and rationality of its expansion, it can provide guidance and suggestions for future urban planning of Xi’an, and promote the sustainable and healthy development of the city.