Redai dili (Mar 2023)
The Temporal and Spatial Evolution Characteristics and Driving Factors of Surface Water in the Guangdong-Hong Kong-Macao Greater Bay Area Since 1985
Abstract
Surface water is an important water resource required for all living things on Earth and the basic resource for human production and living, having great value to mankind. Based on the GEE and ArcGIS platforms, this study uses the global annual surface water dataset from 1985 to 2020 as the main data source and analyzes the spatial and temporal evolution of surface water bodies in the Greater Bay Area (GBA) using the rate of water area change, the density of gridded water bodies, and the land use conversion matrix. We then investigate the relevant influencing factors driving the spatial and temporal evolution of surface water bodies with the assistance of the Geographic Detector. Based on the above findings, and combined with urban development policy and regional development orientation, the spatiotemporal evolution mechanism of surface water bodies in the GBA over the study period was analyzed from the perspective of urbanization development laws. This analysis is also the primary contribution of the study and is the key difference between this research and previous pure geography studies. The results indicate the following: 1) The area change rate of surface water bodies in the GBA shows the characteristics of "slow decline - accelerated decline - deceleration - steady increase;" therefore, the study period is divided into slow shrinkage(1985-2000),accelerated shrinkage(2000-2010),deceleration shrinkage (2010-2015), and steady growth(2015-2020) based on these stage characteristics; 2) The change in the permanent water body area in the GBA has the periodic characteristics of "small cycles of alternating increases and decreases," while the seasonal water bodies area show the change characteristics of "largely decreased first and then increased." The influence of the two types of water bodies on the changes in the total surface water body area shows the characteristics of "alternative domination" with 2010 as the time node; 3) Spatially, large changes in surface water bodies appear in the form of urban clusters. For example, regional urban agglomerations, such as Fo-Guang-Zhao, Shenzhen-Guan-Hui, and Zhu-Zhong-Jiang, show synchronous shrinking or growth in the evolution of water bodies. This is mainly due to urban agglomerations being caused by the transfer (including migration in and out) of land types, such as water bodies, urban construction land, and cultivated land at different periods of urbanization development; 4) From the perspective of the entire study period, natural factors had higher explanatory power for the spatial differentiation of surface water bodies in the GBA than social and economic factors. The explanatory power of annual precipitation and vegetation coverage factors reached 40% and 34%, respectively. There was a two-factor enhanced interaction relationship with multiple factors, among which the explanatory power of cultivated land density and population factors was 31% and 30%, respectively, and there was a non-linear enhanced interaction relationship with multiple factors; and 5) From the perspective of the urban development period, the degree of influence of natural, social, and economic factors on surface water bodies varies across different stages. Natural factors played a leading role in the temporal and spatial differentiation of surface water bodies during the early urbanization process. As urban development accelerated and entered a stable period, the influence of human activities on surface water bodies increased rapidly and became an important driving force for temporal and spatial differentiation.
Keywords