Search

Sustainable territorial spatial development faces severe challenges globally, especially the threats from rapid urbanization. It is important for territorial spatial planning in the new era to explore the principles, methodology and models for the territorial spatial optimization aiming sustainable urbanization from global and national perspectives. This paper rethink the spatial optimization for sustainable development by reviewing the literature on urbanization, spatial optimization and sustainable development. The results show that there is no readymade path for sustainable territorial spatial development, and sustainability should be the fundamental objective of territorial spatial optimization. Cases from the globe and China show that urban sprawl tends to make cities disperse, decline population density, and fall in a path dependency. Cities should be laid at the core of territorial spatial optimization. Chinese sustainable urbanization should be characterized by compact development, high-density, livable urban development, and low carbon. The concepts of sustainable urbanization oriented territorial spatial optimization include ecological protection, resource saving, intensive development, and green development, which forms the path of sustainable territorial spatial development. The modeling of territorial spatial optimization can be reconstructed from index system and quantification, setting of objectives, and constraint rules in a multi-objective collaborative optimization model. In this paper, we conclude that China has to build her own way of sustainable spatial development in accordance with the conditions of the nation, promoted by territorial spatial optimization with sustainable urbanization as a core. [ABSTRACT FROM AUTHOR]

Objectives: Land subsidence in urban areas brings loss of ground elevation, damages urban infra-structure and buildings, and affects surface runoff and hydrological cycle. Monitoring the status of land sub-sidence and revealing its formation mechanism is of great significance for sustainable urban development. Methods: Using ALOS-PALSAR images from 2007 to 2011 and Radarsat-2 images from 2015 to 2019 as data sources, based on SBAS-InSAR technology to obtain the land subsidence rate and time series, and using geographic detectors to reveal the dominant driving factors and the interaction mechanism between the driving factors of land subsidence at the scale of planning unit. Results: The results show that: (1) The average land subsidence rates from 2007 to 2011 and from 2015 to 2019 were − 3.53 mm/a and −1.48 mm/a, respectively. The hot spots for land subsidence from 2007 to 2011 are Hankou, the coast and north of Shahu Lake, the west of Nanhu Lake, and the Baishazhou area. From 2015 to 2019, it is Hankou, the north of Shahu Lake and the Baishazhou area. (2) The temporal and spatial evolution of land subsidence in Wuhan is localized, staged, and related to natural conditions and human activities. Rapid sub-sidence only occur in certain region, shows the different trends at various stages, and is closely related to the regional natural conditions and human activities. (3) Hydrogeological conditions are necessary conditions to form the spatial-temporal pattern of land subsidence in Wuhan through interaction with various factors such as ground load, underground space development, and engineering construction. The interactive effects between engineering construction and hydrogeological conditions from 2007 to 2011 are found to be significant, so do ground load and hydrogeological conditions from 2015 to 2019. Conclusion: The geographic detector can quantitatively identify the driving factors of land subsidence and the interactions between them. The interactive effects between hydrogeological and conditions engineering construction, ground load to a large extent affected spatial variation of land subsidence from 2007 to 2011 and from 2015 to 2019 respectively. In the future, continuous monitoring of land subsidence and multi-scale research on the formation mechanism of land subsidence should be carried out to further enrich the theory and method system of land subsidence research. [ABSTRACT FROM AUTHOR]