Impervious surface Mapping and its spatial–temporal evolution analysis in the Yellow River Delta over the last three decades using Google Earth Engine

Abstract

The unique geographical location of the land-sea transition makes the ecological environment of the Yellow River Delta very fragile and vulnerable to human activities. As one of the characteristics of anthropogenic activities, monitoring the spatiotemporal changes of impervious surface is of great signi cance to the protection of the ecological environment in the Yellow River Delta (YRD). Based on the Landsat historical images and computing resources provided by Google Earth Engine (GEE), an impervious surface area (ISA) mapping method was developed through combining spectral, texture features and random forest algorithm, and subsequently was applied to generate the spatiotemporal distribution data of ISA of the YRD for 1992YRD for , 1998YRD for , 2004YRD for , 2010YRD for , 2016YRD for and 2021. The experimental results demonstrated that the proposed method achieved satisfactory accuracy, with an average overall accuracy of 92.23% and an average Kappa coe cient of 0.9090. Through further time-series analysis of ISA, it found that the area of ISA in the YRD increased from the initial 394.87 km 2 to 1081.74 km 2 during study periods, and the annual growth rate broke through new highs, ranging from the initial 1.01 km 2 /year to 67.87 km 2 /year. According to the research results, urban development activities in the region should be strictly restricted in order to protect the ecological environment of the Yellow River Delta.

Evaluation and Analysis of the Impact of Coastal Urban Impervious Surfaces on Ecological Environments

“…Moreover, the heat island effect was found to decrease when impervious water throughout the spatial gradient also decreased [41], [42] . The limited range of a single city can be broken with the widespread application of impervious surface, and the benefits of quantitative analysis of the spatial continuity of urbanization can be realized [41], [43], [44]. The application of impervious water has developed from research focused on the analysis of the urban surface thermal environment and urban landscape patterns to the analysis of urban ecological environment changes combined with impervious surface data [30], [37], [40], [45] .…”

“…Shao et al analyzed the synergistic effects of changes in driving factors such as impervious water surface and vegetation cover on global or regional ecological environment over a long time series [47], [48]. As the rapid expansion of urban impervious surface has a significant impact on the UHI effect and the quality of the ecological environment, its spatiotemporal evolution not only reflects changes of the spatial structure of urban land-use types, but also represents a major factor influencing the service function of urban ecosystems [11], [44], [49] .Therefore, monitoring the spatiotemporal evolution of impervious surfaces is of great significance for evaluating the health status of urban ecosystems. A large number of studies combined with RSEI have realized the quantitative analysis of the urban ecological environment and temporal and spatial evaluation of ecological security [32], [35], [50], [51].…”

Analysis of changes in the spatiotemporal characteristics of impervious surfaces and their influencing factors in the Central Plains Urban Agglomeration of China from 2000 to 2018

“…Many scholars quantitatively analyze the characteristics of impervious surface changes using methods such as the ISA ratio, area growth amount and growth rate, urban expansion intensity index, etc. [ [18] , [19] , [20] , [21] , [22] , [23] , [24] ]. For example, Jian et al [ 25 ] quantified the dynamic changes of impervious surfaces in Beijing by calculating the percentage of total ISA in 2001 and 2009.…”