Detecting Spatiotemporal Features and Rationalities of Urban Expansions within the Guangdong–Hong Kong–Macau Greater Bay Area of China from 1987 to 2017 Using Time-Series Landsat Images and Socioeconomic Data

The Guangdong–Hong Kong–Macau Greater Bay Area (GBA) of China is one of the major bay areas in the world. However, the spatiotemporal characteristics and rationalities of urban expansions within this region over a relatively long period of time are not well-understood. This study explored the spatiotemporal evolution of 11 cities within the GBA in 1987–2017 by integrating remote sensing, landscape analysis, and geographic information system (GIS) techniques, and further evaluated the rationalities of their expansion using the urban area population elastic coefficient (UPEC) and the urban area gross domestic product (GDP) elastic coefficient (UGEC). The results showed the following: (1) Guangzhou, Shenzhen, Foshan, Dongguan, Zhongshan, and Zhuhai experienced unprecedented urbanization compared with the other cities, and from 1987 to 2017, their urban areas expanded by 10.12, 11.48, 14.21, 24.90, 37.07, and 30.15 times, respectively; (2) several expansion patterns were observed in the 11 cities, including a mononuclear polygon radiation pattern (Guangzhou and Foshan), a double-nucleated polygon pattern (Macau and Zhongshan), and a multi-nuclear urbanization pattern (Shenzhen, Hong Kong, Dongguan, Jiangmen, Huizhou, Zhaoqing, and Zhuhai); (3) with regard to the proportion of area, the edge-expansion and outlying growth types were the predominant types for all 11 cities, and the infilling growth type was the one of the important types during 2007–2017 for Shenzhen, Hong Kong, Dongguan, Zhongshan, and Foshan; (4) the expansion of most cities took on an urban-to-rural landscape gradient, especially for Guangzhou, Shenzhen, Foshan, Zhongshan, Dongguan, and Zhuhai; and (5) the rationalities of expansion in several time periods were rational for Guangzhou (1997–2007), Hong Kong (2007–2017), Foshan (1987–2007), Huizhou (1987–1997), and Dongguan (1997–2007), and the rationalities of expansion in the other cities and time periods were found to be irrational. These findings may help policy- and decision-makers to maintain the sustainable development of the Guangdong–Hong Kong–Macau Greater Bay Area.

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Impacts of Urbanization on the Ecosystem Services in the Guangdong-Hong Kong-Macao Greater Bay Area, China

Remote Sensing ◽

10.3390/rs12193269 ◽

2020 ◽

Vol 12 (19) ◽

pp. 3269

Author(s):

Xuege Wang ◽

Fengqin Yan ◽

Fenzhen Su

Keyword(s):

Hong Kong ◽

Ecosystem Services ◽

Urban Areas ◽

Urban Expansion ◽

Decision Makers ◽

Ecosystem Service Value ◽

The Sustainable Development ◽

The Past ◽

Bay Area ◽

Natural Landscapes

Unprecedented urbanization has occurred globally, which has converted substantial natural landscapes into impervious surfaces and further impacted ecosystem services and functioning. In this study, we quantified the spatiotemporal patterns of urbanization and investigated the impacts of urbanization on the ecosystem service value (ESV) in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) of China from 1980 to 2018. The results show that the GBA has experienced extensive urbanization, with the urban area increasing from 2607.4 to 8243.5 km2 from 1980 to 2018. Zhongshan, Zhuhai, Dongguan, Shenzhen, and Foshan exhibited the top five highest urban expansion rates. Throughout the study period, edge expansion was the most dominant growth mode, with a decreasing trend, while infilling increased in the GBA. The total ESV loss induced by urban expansion in the GBA reached 40.5 billion yuan over the past four decades. The ESV loss due to the water body decrease caused by urbanization was the largest. Our study suggests that decision-makers should control new urban areas and protect water bodies, wetlands, and forests with high ESVs to promote the sustainable development of urban agglomerations.

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An Ecological Service System Based Study on Suburban Rural Landscape Multifunction

Land ◽

10.3390/land10030232 ◽

2021 ◽

Vol 10 (3) ◽

pp. 232

Author(s):

Jie Zheng ◽

Lisha Na ◽

Binglin Liu ◽

Tiantian Zhang ◽

Hao Wang

Keyword(s):

Rural Communities ◽

Urban Areas ◽

Support Function ◽

Service System ◽

Rural Landscape ◽

Dual Function ◽

The Sustainable Development ◽

Ecological Service ◽

Single Function ◽

Data Constraints

Suburban rural landscape multifunction has received increasing attention from scholars due to its high demand and impact on main urban areas. However, few studies have been focused on suburban rural landscape multifunction because of data constraints. The present study quantified the four landscape services based on ecological service system, i.e., regulating function (RF), provision function (PF), culture function (CF), and support function (SF), determined the interaction through the Spearman correlation coefficient, and ultimately identified the landscape multifunction hotspots and dominant functions through overlay analysis. The result indicated that suburban rural communities have exhibited the characteristics of regional multifunction, and the landscape multifunction hotspots accounted for 64.2%; it should be particularly noted that, among single-function, dual-function, and multifunction hotspots, both support function, and culture function was dominant, while only one case was found in which the regulating function was dominant. Furthermore, all landscape functions other than SF-CF exhibited certain correlations. The study suggests that planning and management should be performed in future in combination with landscape multifunction to ensure the sustainable development of suburban rural communities.

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InSAR Multitemporal Data over Persistent Scatterers to Detect Floodwater in Urban Areas: A Case Study in Beletweyne, Somalia

Remote Sensing ◽

10.3390/rs13010037 ◽

2020 ◽

Vol 13 (1) ◽

pp. 37

Author(s):

Luca Pulvirenti ◽

Marco Chini ◽

Nazzareno Pierdicca

Keyword(s):

Urban Area ◽

Urban Areas ◽

The Other ◽

Spatial Average ◽

Calibration Data ◽

Suburban Areas ◽

Persistent Scatterers ◽

Optical Images ◽

Interferometric Phase ◽

Multitemporal Data

A stack of Sentinel-1 InSAR data in an urban area where flood events recurrently occur, namely Beletweyne town in Somalia, has been analyzed. From this analysis, a novel method to deal with the problem of flood mapping in urban areas has been derived. The approach assumes the availability of a map of persistent scatterers (PSs) inside the urban settlement and is based on the analysis of the temporal trend of the InSAR coherence and the spatial average of the exponential of the InSAR phase in each PS. Both interferometric products are expected to have high and stable values in the PSs; therefore, anomalous decreases may indicate that floodwater is present in an urban area. The stack of Sentinel-1 data has been divided into two subsets. The first one has been used as a calibration set to identify the PSs and determine, for each PS, reference values of the coherence and the spatial average of the exponential of the interferometric phase under standard non-flooded conditions. The other subset has been used for validation purposes. Flood maps produced by UNOSAT, analyzing very-high-resolution optical images of the floods that occurred in Beletweyne in April–May 2018, October–November 2019, and April–May 2020, have been used as reference data. In particular, the map of the April–May 2018 flood has been used for training purposes together with the subset of Sentinel-1 calibration data, whilst the other two maps have been used to validate the products generated by applying the proposed method. The main product is a binary map of flooded PSs that complements the floodwater map of rural/suburban areas produced by applying a well-consolidated algorithm based on intensity data. In addition, a flood severity map that labels the different districts of Beletweyne, as not, partially, or totally flooded has been generated to consolidate the validation. The results have confirmed the effectiveness of the proposed method.

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The changes in Mulberry-based fish ponds in the Guangdong-Hong Kong-Macao Greater Bay Area over the past 40 years

10.5194/egusphere-egu21-330 ◽

2021 ◽

Author(s):

Wenxin Zhang ◽

Zihao Cheng ◽

Xianfeng Liu ◽

Gangte Lin ◽

Junan He ◽

...

Keyword(s):

Hong Kong ◽

Water Environment ◽

Fish Ponds ◽

Visual Interpretation ◽

Landsat Images ◽

Rapid Urbanization ◽

Industrial Transfer ◽

Intensity Index ◽

Bay Area ◽

Water Intensity

<p>Mulberry-based fish ponds are representative traditional eco-agriculture in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). Investigations about the changes in such ponds and their relevant water environment under the background of rapid urbanization can provide a reference for the protection and development of these ponds. Using the Landsat images obtained after 1986, this study employed supervised classification and visual interpretation approaches and water intensity index as well as calculating synthesized index to identify the spatial patterns of changes in Mulberry-based fish ponds in the GBA. The results indicated that the year of 2013 was the inflection point of fish pond changes, which can also be proved by calculating synthesized index. The causes to the changes in fish ponds were further explored from four aspects: land use change, industrial transfer, government guidance and financial motives.</p>

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Exploring Annual Urban Expansions in the Guangdong-Hong Kong-Macau Greater Bay Area: Spatiotemporal Features and Driving Factors in 1986–2017

Remote Sensing ◽

10.3390/rs12162615 ◽

2020 ◽

Vol 12 (16) ◽

pp. 2615

Author(s):

Jie Zhang ◽

Le Yu ◽

Xuecao Li ◽

Chenchen Zhang ◽

Tiezhu Shi ◽

...

Keyword(s):

Growth Rate ◽

Hong Kong ◽

Urban Areas ◽

Urban Expansion ◽

Driving Factors ◽

Annual Growth ◽

Annual Growth Rate ◽

Spatial And Temporal Scales ◽

Urban Dynamics ◽

Bay Area

The Guangdong–Hong Kong–Macau Greater Bay Area (GBA) of China is one of the largest bay areas in the world. However, the spatiotemporal characteristics and driving mechanisms of urban expansions in this region are poorly understood. Here we used the annual remote sensing images, Geographic Information System (GIS) techniques, and geographical detector method to characterize the spatiotemporal patterns of urban expansion in the GBA and investigate their driving factors during 1986–2017 on regional and city scales. The results showed that: the GBA experienced an unprecedented urban expansion over the past 32 years. The total urban area expanded from 652.74 km2 to 8137.09 km2 from 1986 to 2017 (approximately 13 times). The annual growth rate during 1986–2017 was 8.20% and the annual growth rate from 1986 to 1990 was the highest (16.89%). Guangzhou, Foshan, Dongguan, and Shenzhen experienced the highest urban expansion rate, with the annual increase of urban areas in 51.51, 45.54, 36.76, and 23.26 km2 y−1, respectively, during 1986–2017. Gross Domestic Product (GDP), income, road length, and population were the most important driving factors of the urban expansions in the GBA. We also found the driving factors of the urban expansions varied with spatial and temporal scales, suggesting the general understanding from the regional level may not reveal detailed urban dynamics. Detailed urban management and planning policies should be made considering the spatial and internal heterogeneity. These findings can enhance the comprehensive understanding of this bay area and help policymakers to promote sustainable development in the future.

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Land Use, Urban Design, and Nonwork Travel: Reproducing Other Urban Areas’ Empirical Test Results in Portland, Oregon

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1722-04 ◽

2000 ◽

Vol 1722 (1) ◽

pp. 27-37 ◽

Cited By ~ 32

Author(s):

Marlon G. Boarnet ◽

Michael J. Greenwald

Keyword(s):

Land Use ◽

Urban Area ◽

Urban Design ◽

Urban Areas ◽

Empirical Test ◽

The Other ◽

Test Results ◽

Trip Generation ◽

New Urbanist ◽

New Variables

Research on nonwork automobile trip generation and land use previously conducted by researchers is replicated for the Portland, Oregon, region. Additionally, new variables examining new urbanist arguments are incorporated. The results suggest that any links between land use and nonwork trip behavior act primarily by influencing trip costs, in terms of distances traveled and speeds achieved, rather than directly influencing the number of trips made. This analysis is consistent with the other research, suggesting that this model is not sensitive to errors that might arise due to the unique characteristics of the urban area under review.

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Nesting of the little bittern Ixobrychus minutus (Aves: Ardeidae) in an urban area of the Crimean coast of the Black Sea

Marine Biological Journal ◽

10.21072/mbj.2017.02.1.02 ◽

2017 ◽

Vol 2 (1) ◽

pp. 11-17

Author(s):

V. E. Giragosov

Keyword(s):

Urban Area ◽

Black Sea ◽

Urban Areas ◽

Aquatic Vegetation ◽

Video Recording ◽

The Black Sea ◽

Natural Landscape ◽

Crimean Peninsula ◽

Bay Area ◽

Ixobrychus Minutus

Observations of the ecological and behavioral adaptations of hydrophilic birds in urban areas are essential for preservation of the biodiversity under extreme anthropogenic transformations of the inland and coastal waters on the Crimean peninsula. In the Crimea a little bittern Ixobrychus minutus (Linnaeus, 1766) nest usually on the fresh and brackish water bodies. For the first time this species was found nesting in Kruglaya bay, the overused recreation area in Sevastopol (Black Sea). Our investigation detected factors determining the breeding efficiency, food spectrum, behavioral responses and the duration of stay of the little bittern in the biotope exposed to high anthropogenic load. Visual observations, photography and video recording were conducted five times a week within Kruglaya bay. Two adult I. minutus were observed from July 3 to August 2, and three immature birds – from July 24 to September 7, 2016 in the bay head. The presence of natural shelter (reed beds) and good feeding base contributed to successful breeding of the birds. The main prey were the juveniles of grey mullet, other preys were peacock blenny Salaria pavo, ocellated wrasse Symphodus ocellatus and invertebrates. The little bitterns showed atypical for this species synanthropic behavior: having gradually adapted to the people neighborhood, they allowed the observer’s presence at 4–6 m distance. In August the young birds began demonstrating territorial behavior and in September they flied beyond the bay area. The study has disclosed high adaptive potential of I. minutus to disturbing factors in atypical to this species habitats in the coastal urban area of the Black Sea. The possibility of little bitterns settling in the fragmentary natural landscape (return urbanization) of urban areas on the Crimean coast of the Black Sea is discussed. Presumably, I. minutus can nest in the semi-aquatic growth bordering some Crimean bays including Kruglaya, Streletskaya, Kazach'ya and Sevastopol bays. The fragments of natural landscape allow preserving the biodiversity; for their protection any building activity ruinous to semi-aquatic vegetation in the coastal zone should be banned.

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MANAJEMEN LIMPASAN AIR HUJAN DI DAERAH PERKOTAAN DENGAN RAIN GARDEN DAN MENJAGANYA DARI KEBERADAAN NYAMUK

Jukung (Jurnal Teknik Lingkungan) ◽

10.20527/jukung.v3i2.4027 ◽

2017 ◽

Vol 3 (2) ◽

Author(s):

Nova Annisa ◽

Hafiizh Prasetia

Keyword(s):

Sustainable Development ◽

Life Cycle ◽

Urban Area ◽

Urban Areas ◽

Descriptive Analysis ◽

Good Treatment ◽

The Other ◽

Rain Garden ◽

Runoff Water ◽

Concrete Layer

ABSTRAKRain garden adalah salah satu praktik pembangunan berkelanjutan untuk mengatasi masalah limpasan air hujan. Rain garden sangat cocok sekali dikembangkan di daerah perkotaan dimana lahan resapan sudah mulai hilang digantikan dengan lapisan beton yang kaku. Tujuan dari kajian ini adalah mengungkapkan bagaimana model rain garden untuk daerah perkotaan dan bagaimana cara untuk menjaganya dari keberadaan nyamuk. Kajian dilakukan dengan analisis deskriptif. Berdasarkan hasil pengamatan diketahui bahwa model rain garden dapat dikembangkan untuk daerah perkotaan. Model rain garden yang satu dan yang lainnya dapat dihubungkan dengan pipa atau gorong-gorong sehingga memungkinkan rain garden berjalan optimal. Rain garden yang bagus harus tidak ada genangan lebih dari 72 jam. Hal ini bertujuan untuk menjaga dari keberadaan nyamuk yang dianggap mengganggu. Perawatan yang bagus terhadap rain garden juga mampu untuk menjaganya dari nyamuk. Kata Kunci: rain garden, nyamuk, siklus hidup ABSTRACT Rain garden is one of sustainable development practices to overcome the problem of runoff water. Rain garden is very well suited to develop in urban areas where the recharge ground has begun to disappear replaced with a rigid concrete layer. The purpose of this study is to reveal how the rain garden model for urban areas and how to guard against the presence of mosquitoes. The study was conducted by descriptive analysis. Based on the observation, it is known that rain garden model can be developed for urban area. Rain garden models that one and the other can be connected with a pipe or culvert that allows rain garden to run optimally. A nice rain garden should have no puddle over 72 hours. It aims to keep from the presence of mosquitoes that are considered disturbing. Good treatment of rain garden is also able to keep it from mosquitoes. Keywords: rain garden, mosquitoes, life cycle

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The Expansion Dynamics and Modes of Impervious Surfaces in the Guangdong-Hong Kong-Macau Bay Area, China

Land ◽

10.3390/land10111167 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1167

Author(s):

Shaohua Zhang ◽

Kun Yang ◽

Yuling Ma ◽

Mingchan Li

Keyword(s):

Hong Kong ◽

Urban Areas ◽

Driving Forces ◽

Urban Expansion ◽

Major Axis ◽

Impervious Surface ◽

Growth Patterns ◽

Limiting Factors ◽

Aggregation Index ◽

Bay Area

Different urban growth patterns have various impact degrees on the urban ecosystem and environment. Impervious surface, a typical artificial construction can be used to reflect urban development. Therefore, this study estimated the spatiotemporal dynamics and expansion patterns of impervious surface area (ISA) in the Guangdong-Hong Kong-Macau (GHM) Bay Area since the establishment of the “Pearl River Delta economic zone” in 1994. Landsat time-series images were used to map the distribution of the ISA based on the combinational biophysical composition index (CBCI) and the bidirectional temporal filtering method (BTFM). The results indicated that the ISA in the GHM Bay Area drastically expanded from 569.23 km2 in 1994 to 10,200.53 km2 in 2016. In addition, the aggregation index (AI) value of the high-density area showed a decreasing trend from 1994 to 2004. However, the value of each landscape metric rapidly increased after 2004. Moreover, the mean ratio of the major axis to the minor axis of standard deviational ellipses from 1994 to 2004 was higher than that from 2005 to 2016. The results of landscape metrics and standard deviational ellipses indicated that the ISA growth pattern changed from edge expanding and leapfrogging to infilling and consolidation, with a turning point in 2004. Moreover, the principal sprawl orientation of the ISA was northwest to southeast before 2004. After 2004, the expansion direction of the ISA was less obvious due to the development pattern of infilling and consolidation. The rapid increase of GDP and population are the driving forces of urban expansion. However, topography and ecological protection policies as the limiting factors, which caused the infilling of the inner city and redevelopment of old urban areas.

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Competition and Sustainability Development of a Multi-Airport Region: A Case Study of the Guangdong–Hong Kong–Macao Greater Bay Area

Sustainability ◽

10.3390/su11102958 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2958 ◽

Cited By ~ 1

Author(s):

Wang Liao ◽

Xiaoshu Cao ◽

Shengchao Li

Keyword(s):

Hong Kong ◽

Urban Areas ◽

Coastal Region ◽

Asia Pacific ◽

Asia Pacific Region ◽

Airline Competition ◽

New Era ◽

Tourist Destinations ◽

Bay Area

A new era in the development of multi-airport regions (MARs) has been in China, especially in the construction of global urban areas such as the Guangdong–Hong Kong–Macao Greater Bay Area (GBA). In order to better understand competition and provide significant advice to support sustainable development of Chinese MARs, this paper takes the GBA-MAR as an example, and then explores the competition between airports in this multi-airport region based on route level and its impact on passenger airport choice using three liner models. According to our findings, competition is concentrated on a few air routes in the Northeast–East Coastal region and the Asia-Pacific region, in which all three airports operate. Although the domestic market of the GBA-MAR has been relatively mature, the international air transport market is still left with considerable room, which is also reflected in connections to the world’s cities and tourist destinations. In addition, the research also found that different airport brands created by route type significantly affected passenger airport choice. Overall, the study revealed that whether from a supply or demand aspect, competition between airports in a multi-airport region—not just airline competition in a single airport—is an important topic.

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