School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China.
Department of Surveying and Mapping Engineering, Henan College of Surveying and Mapping, Zhengzhou 451464, China.
Int J Environ Res Public Health. 2022 Jul 28;19(15):9230. doi: 10.3390/ijerph19159230.
China's "plain-mountain transition zone" (hereinafter referred to as the "transition zone") has experienced rapid and diverse urbanization processes. Assessing the dynamic characteristics of urbanization is particularly important for sustainable development of the transition zone. Nighttime light (NTL) data have been widely used to monitor urbanization. Based on the prolonged artificial nighttime-light dataset of China (PANDA) from 1984 to 2020, we partitioned the nighttime light of the study area into four types (low, medium, high, and extremely high) by adjusting the threshold of the brightness gradient (BG) method. The spatiotemporal characteristics of urbanization in 426 districts and counties of 71 prefecture-level cities in the transition zone were analyzed. Our results indicated that the middle region of the transition zone (Yanshan Mountains and Taihang Mountains) experienced the fastest urbanization development, and the urban expansion speed broke through the topographic limitation of the plain-mountain. However, the rapid development of urbanization in the middle plains resulted in the nighttime lighting area (NTLA) tending to become saturated, which caused an unsustainable potential crisis in urban development in this area. Urbanization was mainly manifested in the transition of the low nighttime lighting type (NTLT) to the medium NTLT or higher NTLT. The northern region of the transition zone (Greater Khingan Mountains) experienced the slowest urbanization development, with the lowest nighttime lighting density (NTLD) in the northern mountainous area, where the urbanization was mainly manifested by the expansion of the low NTLT. The urbanization development of the southern region in the transition zone (Wushan and Xuefeng Mountains) was at a medium level, and the urbanization of the plain in the southern region was also better than that of the mountainous area. Urbanization was mainly manifested in the expansion of the low NTLT, supplemented by the transition from the low NTLT to high NTLT. Whether in the north, middle, or south of the transition zone, the plain-mountain topographic variations caused a gap in urbanization, making the urbanization development of the mountains and plains unbalanced.
中国的“山前过渡带”（以下简称“过渡带”）经历了快速而多样化的城市化进程。评估城市化的动态特征对于过渡带的可持续发展尤为重要。夜间灯光（NTL）数据已被广泛用于监测城市化。基于中国从 1984 年到 2020 年的长时间人工夜间灯光数据集，我们通过调整亮度梯度（BG）方法的阈值，将研究区域的夜间灯光分为四类（低、中、高和极高）。分析了过渡带 71 个地级市的 426 个区和县的城市化时空特征。结果表明，过渡带中部（燕山山脉和太行山脉）的城市化发展最快，城市扩张速度突破了山前平原的地形限制。然而，中部平原城市化的快速发展导致夜间灯光面积（NTLA）趋于饱和，这给该地区的城市发展带来了不可持续的潜在危机。城市化主要表现为从低夜间灯光类型（NTLT）向中或高 NTLT 的转变。过渡带北部（大兴安岭）的城市化发展最慢，北部山区的夜间灯光密度（NTLD）最低，城市化主要表现为低 NTLT 的扩张。过渡带南部地区（巫山和雪峰山）的城市化发展处于中等水平，南部平原的城市化也优于山区。城市化主要表现为低 NTLT 的扩张，辅以低 NTLT 向高 NTLT 的转变。无论是在过渡带的北部、中部还是南部，山前地形的变化导致了城市化的差距，使山区和平原的城市化发展不平衡。
