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Objectives: As the acceleration of global urbanization, traffic congestion and environmental degradation have emerged in the urban area. Based on the light and statistical data, this paper studied the spatial evolution between urban people and land, and revealed the significance of its coupling and coordination characteristics for the sustainable development of cities. Methods: For primary data, a series of preprocessing are needed to eliminate the problems of supersaturation and discontinuity of inter‑annual data. Based on the lighting threshold, this paper excerpted the built‑up areas of urban agglomeration in Zhejiang Province year by year, compared them with the statistical data, and analyzed the corrected data source relatively. Firstly, based on the order‑scale distribution model of urban order and urban population in Zhejiang Province from 1992 to 2020, we made a dynamic analysis on population aggregation and distribution in its development process. Then, we constructed the population‑land urbanization allometric growth model by using population and light area, as well as judged the spatialization of man‑land relationship in urban development. Finally, according to the lag phenomenon of population growth relative to land development, we proposed an allometric growth model with lag factor, and used the lag term model to judge the characteristics of unequal growth of people and land in different cities. Results: The structural system of urban agglomeration is relatively mature in Zhejiang Province, and the distribution of cities is reasonable. However, the primacy of city is gradually improved, and the population is gradually gathering. The results of allometric growth model show that the man‑land relationship of urban agglomeration in Zhejiang Province is generally low in the eastern coastal cities and high in the western inland cities, and the planning of the four metropolitan areas is reasonable. The improvement of fitting accuracy of the proposed model with lag factor obviously shows that there is lag effect between population urbanization and land urbanization, with an average increase of 6.47% and the highest increase of 12.61%. Among the influencing factors on land urbanization, the dominant factor in Hangzhou is the existing population in urban areas, while the dominant factor in Ningbo is the new population in urban areas. Conclusions: The proposed allometric growth model with lag factor can correct the model errors and improve the fitting accuracy of urban man‑land relationship. It can also effectively evaluate the temporal and spatial evolution characteristics of man‑land relationship in regional system, explore its development and put forward countermeasures. [ABSTRACT FROM AUTHOR]

Objectives: It is important to know the pattern of Pakistan̓s regional development for the construction of China‑Pakistan Economic Corridor. Methods: We used visible infrared imager radiometer suite (VIIRS) nighttime light remote sensing image as the main data source, and implemented Savitzky ‑ Golay (SG) filtering algorithm to repair the missing values of the images. Night time light change ratio (NLCR), Mann ‑ Kendall(MK) trend test method and rank ‑ size rule were carried out to study the nighttime light change patterns of province level, city level, geographic grid level, and east‑west zone in Pakistan. Results: The analysis result of NLCR shows that from 2012 to 2019, NLCR of the entire Pakistan is 47.96% and all provincal regions has developed to a certain degree with NLCR larger than 15%. NLCR of Gwadar Port is 126.94%, which is the highest in 15 node cities on east and west lines of China‑Pakistan Economic Corridor. Additionally, the development of 15 node cities on east and west lines of China ‑ Pakistan Economic Corridor was unbalanced. The results of MK trend test show that at the geographic grid scale of 5 km, there are 1 905 grids with the total nighttime light upward trend in Punjab and 338 grids with the total nighttime light downward trend in Sindh. It is found that most grids with the total nighttime light downward trend are located in rural areas of Sindh, which is consistent to the fact that there is a serious power shortage problem in rural areas of Sindh. The analysis results of rank‑size rule show that the Pareto indexes of both eastern and western zones are gradually decreased, indicating that the distribution of urban size in Pakistan becomes more balanced. And the lack of stable power supply may be the reasons for the low brightness of nighttime light in some areas. Conclusions: The regional development patterns of Pakistan under long‑term time series and multiple spatial scales can provide a certain scientific basis for the planning of China‑Pakistan Economic Corridor. [ABSTRACT FROM AUTHOR]