Quantification of Urban Patterns and Processes through Space and Time Using Remote Sensing Data: A Comparative Study between Three Saudi Arabian Cities

Abstract

Saudi Arabia has developed rapidly over the last five decades in the wake of an extensive development programme implemented by the government throughout the entire country. Several previous studies have measured the extent and rate of urbanization in Saudi Arabian cities, but most of this research used only remote sensing data or a single index to explain urban growth patterns. This study used satellite data and a set of landscape metrics to quantify the spatiotemporal urban growth patterns and processes in three Saudi Arabian cities–Riyadh, Jeddah and Makkah. First, Landsat images were collected and classified for the years 1985, 1990, 2000, 2007, 2014 and 2020. Classification was carried out through an object-based image analysis (OBIA) to map the extent of urbanization. The classified maps were then used to compute seven landscape metrics to determine the spatial configuration of urban areas. The spatial metrics were calculated for the entire landscape and across buffer zones that were delineated from the urban core centre of each city. The overall accuracies were >94% for all the classified maps. The spatiotemporal results indicated that all three cities have experienced significant urban growth during the last four decades. Urban patterns in Jeddah were more dispersed than in Riyadh, which showed aggregated patterns (especially in recent years), while urban growth in Makkah tended to be more fragmented. The urban form in Riyadh was relatively simple, while a complex form was associated with Makkah and Jeddah. Understanding the rates, patterns, processes and trajectories of changes to urban land use is essential for various decision-making processes.

Revisiting Urban Resilience: A Systematic Review of Multiple-Scale Urban Form Indicators in Flood Resilience Assessment

“…Edge density refers to the amount of perimeter or edge relative to the area of a landscape patch or urban district, and it plays a significant role in FR by influencing water flow patterns and connectivity. Higher edge densities in urban areas result from irregularly shaped patches, intricate street networks, or fragmented land use patterns [103,104,288]. Excessive edge density can lead to localized flooding without proper stormwater management infrastructure.…”

“…It implies that smaller, more manageable units can be more easily managed and adapted to changing conditions, including climate change and increased flood risk [36,140,205]. However, the effectiveness of patches in enhancing FR depends on several factors, including the size and distribution of the patches, the types of land uses within each patch, and the presence of buffer zones or green corridors that can absorb and store floodwater [187,288,294]. For example, tiny or poorly connected patches may not effectively reduce flood risk.…”

“…Landscape percentage [20,288] A compensation metric that measures the percentage of landscape belonging to urban areas Positive Open space index [10] Open space index describes the relationship between unbuilt space and the total built surface. Positive…”

“…Number of patches [101,288] The number of urban patches in a city or urban area is a critical metric in urban morphology, reflecting the complexity and diversity of urban landscapes.…”

The Interplay between Spatial Urban Expansion and Morphologic Landscapes East of Cairo, Egypt Using Time Series Satellite Imagery

“…Because of the high spatial resolution, CORONA images have recently been used in studies relating to urban expansion [3,54,55]. In addition, Earth observation satellites, such as Landsat, ASTER, and SPOT, allow scientists from many disciplines to manage spatial urban expansion throughout numerous geographic areas worldwide [56][57][58][59][60][61][62]. Observing the 1.8 spatial resolution CORONA images acquired in 1969 provides the unprecedented opportunity to explore the initial morphologic features of watersheds east of Cairo, and their spatial characteristics, in fine detail from totally different perspectives.…”