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Urban park green spaces have the functions of improving the urban ecological environment and providing recreational services, and at the same time, they have a certain effect on the value of the surrounding residential property. To quantitatively assess the value of the landscape premium function of park green space, many scholars have carried out research exploration and adopted a variety of methods (such as the contingent valuation method (CVM), travel cost method (TCM) and hedonic price method (HPM)), which have developed from simple theoretical models with single factors to complex empirical models with multiple factors. Among them, the hedonic price method has become the mainstream research method, and in recent years, it has been widely adopted in combination with GIS technology. In terms of research objects, single park green space or multiple park green spaces in large cities are the main focus, while there are fewer studies on park green spaces in built-up areas of small and medium-sized cities. In terms of research content, there are more studies on the value-added coefficient of landscape premium and influence distance, and there are fewer studies on the total value of landscape premium. This article aims to calculate the total landscape premium value of all park green spaces in the built-up areas of small and medium-sized cities, proposing a complete and operable accounting system for the functional value of park green space landscape premiums by combining GIS with a hedonic pricing model and remote sensing image interpretation methods. For the first time, a method for interpreting the height of residential buildings within the benefit range of landscape premium through remote sensing images is proposed, and then the floor area ratio of residential plots is estimated, so as to estimate the total area of actual beneficial buildings. Therefore, this paper takes Chifeng City, a small and medium-sized city, as a case study, and empirically demonstrates the assessment of the landscape premium function of parks and green spaces in the built-up area of Chifeng City by using this accounting system. Research shows that this method has certain feasibility, not only calculating the total value of landscape premium but also addressing the issue in existing studies where all areas within the potential range of landscape premium function are counted as appreciated areas, leading to an overestimation of the premium. It further advances the accuracy of accounting for the value of landscape premium function of urban park green space and provides theoretical reference for the planning and construction of urban park green space. [ABSTRACT FROM AUTHOR]

The primary aspect of socioeconomic development is health. One of the most important factors influencing health care utilization and access is the accessibility of health services, which have an impact on people’s health, Madurai district. The study area is located in Madurai district, a southern region of Tamil Nadu. The current study illustrates how patients’ perceptions age and sex characteristics relate to the accessibility of primary health care in the Madurai region. The study aimed to assess the accessibility of PHC with sex and age indicators. To understand patients’ perceptions and satisfaction levels with these PHC services. The data for the present study was collected from primary and secondary sources. The random sampling technique was adopted to collect the primary data in all 13 blocks, and in each block, 20 questionnaires were collected. 260 sample respondents have been interviewed from the study area. The patients’ satisfaction level was based on the district average. The data has been analyzed by means of descriptive statistical techniques and identified the proximity of the health centers by buffer method, multiple ring buffer method, and overlay analysis by Arc GIS 10.3 software platform. To access the health service area in Madurai District, spatial analysis techniques were applied. Access to PHC was done using graphic techniques such as Thiessen polygon, overlay analysis, Rn statistics, and Z-score analyses. This study describes patients' perceptions and travel behaviors, patterns among sex and age variations, and healthcare planning for PHCs in Madurai District. [ABSTRACT FROM AUTHOR]

Since 2008, annual outbreaks of green tides in the Yellow Sea have had severe impacts on tourism, fisheries, water sports, and marine ecology, necessitating effective interception and removal measures. Satellite remote sensing has emerged as a promising tool for monitoring large-scale green tides due to its wide coverage and instantaneous imaging capabilities. Additionally, drift prediction techniques can forecast the location of future green tides based on remote sensing monitoring information. This monitoring and prediction information is crucial for developing an effective plan to intercept and remove green tides. One key aspect of this monitoring information is the green tide distribution envelope, which can be generated automatically and quickly using buffer analysis methods. However, this method produces a large number of envelope vertices, resulting in significant computational burden during prediction calculations. To address this issue, this paper proposes a simplification method based on azimuth difference and side length (SM-ADSL). Compared to the isometric and Douglas–Peucker methods with the same simplification rate, SM-ADSL exhibits better performance in preserving shape and area. The simplified distribution envelope can shorten prediction times and enhance the efficiency of emergency decision-making for green tide disasters. [ABSTRACT FROM AUTHOR]

Clarifying the spatiotemporal distribution and influencing factors of mosque architecture in China's Hehuang region has significant positive implications for the overall protection and development of the region's architectural cultural heritage. This study utilizes field surveys and acquires POI data of traditional mosques built before 1993 in the region to analyze the distribution characteristics of mosques, aiming to explore future development trends of these religious structures. It also investigates the influencing factors, with the goal of emphasizing the primary and secondary factors affecting mosque distribution. The study finds the following: (1) Mosques are generally centered around the Huangshui Valley, displaying a "central clustering, peripheral dispersal" distribution pattern, forming a spatial structure of "two cores, one belt, multiple points", with distinct differentiation and overall uneven distribution. (2) Mosques are primarily situated at elevations between 2147 and 2764 m; on slopes less than 15°, in sunny and gentle slopes; within 20 km from rivers; within 14 km from roads; in areas receiving 400–500 mm annual rainfall; and within temperature ranges of 5.54–10.22 °C. (3) The study also finds that the spatial distribution of mosques is profoundly influenced by both natural geographical factors and human environmental factors. The better the natural location, the larger and denser the population, the richer the cultural resources, the higher the level of economic development, and the greater the concentration of Hui people, the more numerous and concentrated the mosques. (4) Population factors are the dominant factors for the clustered distribution of traditional mosques in the Hehuang area. Since the construction of mosques in the region is closely related to the number of Hui people and the proportion of Muslim adherents, areas with a high concentration of mosques also have relatively larger populations of Hui people. Temperature, precipitation, altitude, rivers, and roads are foundational factors for traditional mosques in the Hehuang area, influencing mosque distribution as external factors. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The assessment of sustainable tourism development in the rural areas of the Aktobe oblast of Kazakhstan involved thoroughly analyzing multiple dimensions. Environmental, socio-economic, and cultural sustainability aspects were considered to comprehensively understand the region's tourism potential. The study began by evaluating the available tourism resources in rural Aktobe. This included assessing natural attractions such as landscapes, wildlife, and geological features, as well as cultural heritage sites and infrastructure like accommodation facilities and transportation networks. A crucial aspect of the study was to analyze the environmental impact of tourism activities in rural areas. This involved evaluating the effects on ecosystems and natural resources. The measures for conserving these resources were also identified. Another focus was on the socio-cultural aspects of tourism development. The study aimed to preserve local traditions, cultural heritage, and community identity amidst tourism growth. Strategies for achieving socio-cultural sustainability were devised. Ranking methods were employed to identify key factors influencing rural tourism development. These methods helped prioritize areas for improvement and resource allocation. A balanced approach was adopted to assess the interaction between different dimensions of sustainability. This ensured that environmental, economic, and socio-cultural aspects were considered equally to achieve overall sustainable tourism development. ArcGIS 10 was used for data analysis and visualization. Maps and charts were created to represent spatial and statistical information, aiding in identifying trends and patterns. The study findings were crucial for identifying priority areas for infrastructure development and formulating strategies and programs for rural tourism promotion. The study aimed to ensure that tourism development aligns with the principles of sustainable development, benefiting both the local communities and the environment. The study provided valuable insights into the current status of rural tourism in Aktobe oblast and offered recommendations for sustainable development, contributing to the region's long-term prosperity. [ABSTRACT FROM AUTHOR]

The continuous process of urbanization and climate change has led to severe urban heat island (UHI) effects. Constructing parks with cooling capabilities is considered an effective measure to alleviate UHI effects. However, most studies only quantify the cooling effect from a maximum value perspective, lacking a measure of temperature diffusion in space. This study combines the perspectives of maximum value and accumulation to define a cold island index, quantifying the cooling effect of 40 urban parks in the main urban area of Xi'an city. The results show that, on average, urban parks can reduce the surrounding environment by approximately 2.3℃, with a cooling range of about 127.1ha, which is three times the park area. Different factors drive the measurement of the cooling effect using different cold island indexes, but all indexes are highly correlated with green space area. There are significant differences in the cooling effect among different types of parks, and overall, ecological parks have the best cooling effect. The directional spread of internal cold islands in parks is most related to park shape, while external spread is related to surrounding green spaces. The research results have practical value in the construction of parks with cooling effects and the sustainable development of cities in urban planning processes..

Since 2008, annual outbreaks of green tides in the Yellow Sea have had severe impacts on tourism, fisheries, water sports, and marine ecology, necessitating effective interception and removal measures. Satellite remote sensing has emerged as a promising tool for monitoring large-scale green tides due to its wide coverage and instantaneous imaging capabilities. Additionally, drift prediction techniques can forecast the location of future green tides based on remote sensing monitoring information. This monitoring and prediction information is crucial for developing an effective plan to intercept and remove green tides. One key aspect of this monitoring information is the green tide distribution envelope, which can be generated automatically and quickly using buffer analysis methods. However, this method produces a large number of envelope vertices, resulting in significant computational burden during prediction calculations. To address this issue, this paper proposes a simplification method based on azimuth difference and side length (SM-ADSL). Compared to the isometric and Douglas–Peucker methods with the same simplification rate, SM-ADSL exhibits better performance in preserving shape and area. The simplified distribution envelope can shorten prediction times and enhance the efficiency of emergency decision-making for green tide disasters.

Previous studies have provided valuable insights into the impact of green space (GS) on land surface temperature (LST). However, there is a need for in-depth comparative research on changing landscape patterns in cities and their effects on the urban thermal environment. This study investigates the spatial arrangement of GS and the influence of impervious surfaces on LST in urban areas, examining their cooling and warming effects in the urban landscapes of Beijing and Islamabad. The study aims to assess the impact of the spatial arrangement of GS on LST using a moving window of 1 km2 to analyze the overall effect of landscape patterns on the urban environment. Using Gaofen (GF–2) and Landsat–8 satellite data, we examined the biophysical surface properties of core urban areas. The results indicate a significant difference in the mean LST of 5.44 °C and 3.31 °C between impervious surfaces and GS in Beijing and Islamabad, respectively. The barren land and GS in Islamabad experience a higher LST of 3.39 °C compared to Beijing, which accounts for 1.39 °C. In Beijing, configuration metrics show no significant effect on urban LST, while edge density (ED) exhibits a slightly negative trend. In contrast, in the city of Islamabad, the landscape shape index (LSI), patch density (PD), and number of patches (NP) metrics have a significant influence on LST. The cooling effect of GS patches (0.1–0.5 ha) is more pronounced, while that of GS patches of 15–20 ha shows no significant effect on LST. The temperature difference (TD) of 5.01 °C was observed from the edge of GS in Beijing and 3.3 °C in Islamabad. Considering Islamabad's lush green scape compared to Beijing, this study suggests that Islamabad may experience an increase in LST in the future due to urbanization. This study's findings may assist urban policy-makers in designing sustainable green city layouts that effectively address future planning considerations.

For urban growth modeling, assessment metrics derived from cell-by-cell comparisons are mainly related to the size of the study area and the urban growth rate. Non-urban areas always occupy an important part of the city to which cellular automata (CA) models do not contribute much, so the simulation accuracy is often exaggerated when this part is included. To enable comparing simulation results across models, regions, and time, we developed an improved equivalent area-based assessment (EQASS) method using cell-by-cell comparison metrics. As against existing assessment methods, EQASS is computed by including the same area of urban and suburban areas (i.e., equivalent areas). EQASS was tested in three Chinese coastal cities using a heuristic CA model and two spatial statistical CA models to simulate urban growth. The results show that EQASS can exclude correct rejections that are not attributable to CA models; these correct rejections have a significant impact on the model assessment. The improved assessment can better evaluate the performance of CA models across regions and over time than the conventional assessment method that accounts for the full study area. This study extends the simulation assessment method and provides a good solution for selecting the best CA model from many candidate models. [ABSTRACT FROM AUTHOR]

Clarifying the spatiotemporal distribution and influencing factors of mosque architecture in China’s Hehuang region has significant positive implications for the overall protection and development of the region’s architectural cultural heritage. This study utilizes field surveys and acquires POI data of traditional mosques built before 1993 in the region to analyze the distribution characteristics of mosques, aiming to explore future development trends of these religious structures. It also investigates the influencing factors, with the goal of emphasizing the primary and secondary factors affecting mosque distribution. The study finds the following: (1) Mosques are generally centered around the Huangshui Valley, displaying a “central clustering, peripheral dispersal” distribution pattern, forming a spatial structure of “two cores, one belt, multiple points”, with distinct differentiation and overall uneven distribution. (2) Mosques are primarily situated at elevations between 2147 and 2764 m; on slopes less than 15°, in sunny and gentle slopes; within 20 km from rivers; within 14 km from roads; in areas receiving 400–500 mm annual rainfall; and within temperature ranges of 5.54–10.22 °C. (3) The study also finds that the spatial distribution of mosques is profoundly influenced by both natural geographical factors and human environmental factors. The better the natural location, the larger and denser the population, the richer the cultural resources, the higher the level of economic development, and the greater the concentration of Hui people, the more numerous and concentrated the mosques. (4) Population factors are the dominant factors for the clustered distribution of traditional mosques in the Hehuang area. Since the construction of mosques in the region is closely related to the number of Hui people and the proportion of Muslim adherents, areas with a high concentration of mosques also have relatively larger populations of Hui people. Temperature, precipitation, altitude, rivers, and roads are foundational factors for traditional mosques in the Hehuang area, influencing mosque distribution as external factors.

Based on a study of the spatial distribution of coffee shops in the main urban area of Beijing, the main influencing factors were selected based on the multi-source space data. Subsequently, three regression models were compared, and the best site selection model was found. A comparison was performed between the prediction model functioning with a buffer and without one, and the accuracy of the location model was verified by comparing the actual change trend and the predicted trend in two years. The following conclusions were obtained: (1) coffee shops in the main urban area of Beijing are clustered in an area within 12 km of the main urban center, and also around the core commercial agglomeration area; (2) the random forest (RF) model is the best model in this study, and the accuracy values before and after buffer analysis were 0.915 and 0.929, respectively; and (3) after verifying the accuracy of the model through two years of data, we recommend the establishment of a main road buffer zone for site selection, and the success rate of site selection was found to reach 72.97%. This study provides crucial insight for coffee shop prediction model selection and potential store location selection, which is significant to improving the layout of leisure spaces and promoting economic development. [ABSTRACT FROM AUTHOR]

Parks and recreational spaces play a major role in upgrading the living conditions of urban areas. Easily accessible public parks are a crucial aspect of sustainable urban planning. The objective of this study is to assess the level of serviceability of public parks in terms of accessibility, and spatial distribution of neighbourhood and city parks. The data obtained from USGS Earth Explorer and Google Earth software, and was put in ArcGIS 10.2 software for creating land use land cover map of study area. Methods of buffer and network analysis were used for accessibility analysis of public parks category-wise. The catchment area limit is set as 300 m and 800 m for neighbourhood park and city park respectively. The results reveal the clear distinction in the availability of parks across the study area. Moreover, study findings may help concerned authorities and stakeholders to the creation of standards for the delivery of parks and green spaces. [ABSTRACT FROM AUTHOR]

Understanding the impact of urbanization on groundwater quality is critical. Effective water management requires understanding the relationship between land use and water quality. The study's goals were to compare the effects of land use, identify the types of land that impact hydrochemistry, and define how different land use affects water quality. For this purpose, the comparative relationship between groundwater quality, land use classes and landscape metrics were established for the years 2016 and 2021. Water samples were collected from 42 wells, and different hydro-chemical variables were considered to calculate the water quality index (WQI). The WQI value in 2016 ranged from 26.49 to 151.03 and 29.65 to 155.62 in 2021. The results indicate that the water quality in most parts of the study area is moderate for drinking and domestic purpose use. The google earth engine platform was used and radiometrically corrected and orthorectified Sentinel-2 satellite images were processed to classify land use classes for selected years. Five buffer zones were established within a 2-km watershed along each well site, and the effects of land use types and landscape metrics on water quality in the buffer zones were analyzed. Results revealed that the effects of land use types on water quality were mainly reflected in buffer 1 (B1), buffer 4 (B4), buffer 5 (B5) in 2016 and B1, buffer 3 (B3), and B5 in 2021. The impacts of landscape-level metrics on water quality are mainly reflected in buffer 2 (B2) and B3 in 2021, while at the class-level, they are mainly reflected in B1 and B4 in 2021. The redundancy analysis revealed that different hydro-chemical variables behaved differently with the land use classes and landscape metrics in the various buffer zones. [ABSTRACT FROM AUTHOR]

Objectives: Buffer analysis is a common tool of spatial analysis, which deals with the problem of proximity. Due to numerous and complex operations in the algorithm, the computational efficiency needs to be optimized. Methods: To process large scale point features, a graph-based representation model is pro⁃ posed, which establishes the spatial computational domain for data and analysis, and develops a well-balanced task-partitioning method by partitioning the graph. First, the proposed model defines processing functions of point features and their spatial relationships from the perspectives of graph nodes and graph edges, and provides a logic description for buffer zone generation around point features. Second, the computational weights of graph nodes and graph edges are obtained by fitting the time complexity of the above processing functions. Finally, graph partitioning is adopted to divide the buffer task, which contributes to multiple parallel tasks matching with the computational resources. Results: The experimental results show that graphbased buffer analysis can achieve better load balance and overall efficiency, which is superior to the main⁃ stream partitioning methods, regular-grid and quadtree. Conclusions: The proposed method can provide a reference for optimization of spatial analysis methods when processing large scale vector data. [ABSTRACT FROM AUTHOR]

Hyderabad's recreational amenities have made limited progress in comparison to the development of its industrial and commercial sectors. People require parks to unwind from their hectic lives. Parks can be a healthy location to host social events and can enhance community bonds. The evaluation of park accessibility has not been considered over the years in Hyderabad. Hyderabad is the eighth largest settlement in Pakistan and the second largest in the Sindh province. Thus, this study aimed to evaluate the spatial accessibility of the urban parks situated in the city's distinct locations. The spatial distribution of parks throughout the city was determined in this research. This study evaluated how accessible urban parks are to users by conducting a buffer analysis with ArcGIS-10.8. The questionnaire survey was conducted to record the participants' opinions about the existing conditions of the parks with a sample size of 400. There was a total of 28 inaccessible urban parks found in Hyderabad. The total facility coverage was decided to be 0.80%. This value is extremely low as per local standards. Therefore, this study recommends the planned development of 40–45 parks to reach the standard level of 18% of the park coverage area. This study suggests that government officials should take pivotal measures to better maintain parks. This research is significant in the advanced modern world because natural areas, such as parks, can offer social and psychological benefits to society. The accessibility of parks is essential for the prosperity of citizens and the achievement of sustainable development goals. The findings of this research may contribute to SDGs 3 and 11, i.e., good health and well-being and sustainable cities and communities. [ABSTRACT FROM AUTHOR]

Cities serve as hubs for various activities that necessitate comprehensive transportation connectivity. This study examines the decadal urban agglomeration patterns from 2001 to 2020 and critically assesses the relationship between freeway developments, industrial relocation, and population density in the DFW (Dallas Fort Worth) metropolitan area. Landsat satellite imageries, US census, and open-source GIS datasets have been utilized in the study. The Maximum Likelihood Classification (MLC) algorithm helped generate the vector database, using which Land Use/Land Cover (LULC) variations were assessed. The calculated overall accuracies of the classified images for 2001, 2011, and 2020 were 93.12%, 91.87%, and 93.12%, respectively. Eventually, buffer generation techniques and summary statistics helped detect potential boom hotspots. Our results indicate that the highway advancement project lures industries, leading to population migration. The LULC variations suggest that the increase in highway infrastructure resulted in a surge in built-up and a decrease in open spaces in District-3 of DFW. From our study, we find that 79.16% of old industries are located near old freeways, while 78.84% of new industries are located near new freeways. Further, our industrial area to road area comparison clearly shows that industrial relocation was driven by transportation advancements over time. Our results also confirm that this relocation of industries fostered a massive population influx during the following decades. [ABSTRACT FROM AUTHOR]

Roads, due to their large spatial scale, significantly affect the landscape, causing numerous and usually irreversible changes. Due to a lack of consensus among various specialists and varying evidence on the extent of the influence of roads, the present study focused on the clarification of the real range of the effect of roads on the environment, especially the landscape structure. The aim of the study was to assess road-effect zones for different types of land use. The existing sections of the European route E30 in the Wielkopolska region (Poland) were selected for the research. Based on buffer analysis, landscape metrics and statistical analysis, such as cluster analysis and changes in mean and variance, the spatial diversity of the landscape and road-effect zone was characterized. The results indicate the spatial diversity of the landscape structure and the range of impact, which depended on the type of land cover. Therefore, to analyze the road-effect zone, it is necessary to take into consideration not only the variable range of impact due to the type of road or the time of exploitation, but also the different types of land use of areas surrounding the road. [ABSTRACT FROM AUTHOR]

Based on a study of the spatial distribution of coffee shops in the main urban area of Beijing, the main influencing factors were selected based on the multi-source space data. Subsequently, three regression models were compared, and the best site selection model was found. A comparison was performed between the prediction model functioning with a buffer and without one, and the accuracy of the location model was verified by comparing the actual change trend and the predicted trend in two years. The following conclusions were obtained: (1) coffee shops in the main urban area of Beijing are clustered in an area within 12 km of the main urban center, and also around the core commercial agglomeration area; (2) the random forest (RF) model is the best model in this study, and the accuracy values before and after buffer analysis were 0.915 and 0.929, respectively; and (3) after verifying the accuracy of the model through two years of data, we recommend the establishment of a main road buffer zone for site selection, and the success rate of site selection was found to reach 72.97%. This study provides crucial insight for coffee shop prediction model selection and potential store location selection, which is significant to improving the layout of leisure spaces and promoting economic development.

Copyright of Mavi Atlas is the property of Mavi Atlas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Riparian vegetation and built-up density along the urbanised section of the Calabar river were estimated using NDVI (Normalised Differential Vegetation Index) and NDBI (normalised differential built-up index), respectively. Four sampling stations representing riparian density and built-up gradients i.e. Station 1 (sparse riparian + high-density built-up), 2 (sparse riparian + high to intermediate-density built-up), 3 (moderate riparian + intermediate to low-density built-up) and station 4 (moderate riparian + low-density built-up) were selected. Station-specific variations of metal (Pb, Cd, Cr, Fe and Cu) in surface water and benthic macro-invertebrate communities were examined between January and December 2013 and correlated using redundancy analysis (RDA). Buffer analysis revealed that stations having low NDBI with over 120 m dense riparian areas showed a marked abundance of muddy/coarse substrate while sparse riparian areas showed siltier and sandier substrate. Redundancy analysis revealed a marked delineation of macroinvertebrate occurrence with the riparian density of stations. High diversity macroinvertebrate assemblages showed a strong positive association with alkaline pH, the density of riparian vegetation and substrate type. This first report highlights the critical relationship between riparian density, water quality and benthic macroinvertebrates in a tropical river. [ABSTRACT FROM AUTHOR]

Rapid population growth and high rate of urbanization make municipal solid waste management a challenging task for municipalities. Lack of sufficient infrastructural facilities worsen this challenging situation. To curb this, transfer stations, which are facilities located close to residential areas and are used to receive and hold waste temporarily until it is transported to distant landfills. It reduces waste transportation cost and provide a place for waste segregation. In Lahore open transfer station is built near river Ravi and residential areas which is creating air and land pollution. This study is carryout to select the suitable location for waste transfer station in Lahore that meets the USEPA criteria. Buffer command of Arc GIS is used for site selection. Best suitable sites selected for Lahore in this analysis are UC Sultanki and UC Chandrai where more buffers are joint during buffer analysis. Furthermore, cost estimation for the construction and operation of both waste transfer stations are done.

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geomatik is the property of Murat Yakar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mediterranean stone pine reforestations are common characteristics of the Italian Tyrrhenian coast, which mostly maintain uniform and monolayered stand structures. However, improving structural diversity is an effective climate change adaptation strategy in forest management. The aim of this study was to implement a methodology which allows distinct reforested areas such as a single green infrastructure to be managed according to the surrounding land use and the characteristics of the forest stands. 240 hectares of Mediterranean stone pine forests located along a 16 km strip of the Lazio coast (Central Italy) were mapped. Twelve attributes describing the pine stands and showing possible constraints for future management decisions were associated to each forest patch. A hierarchical cluster analysis was performed to group the pinewood patches according to their similarity level and five different groups were identified. For each group, different silvicultural methods were proposed to guide the compositional and structural evolution of the stands, in order to make them suitable for providing services required locally and increasing overall diversity at landscape scale. The results of the study highlight how coastal land uses can offer effective inputs to differentiate the management of forest systems and therefore achieve greater variety and resilience in the landscape over time. This approach is particularly useful in the case of very homogeneous stands such as the stone pine reforestations under study. [ABSTRACT FROM AUTHOR]

Ecological Security Patterns (ESPs) are important nature-based solutions for ecological problems caused by urbanization and industrialization. Previous studies on ESPs focus on natural conditions only, yet do not incorporate the need for social equity. This study aims to address this quandary for the study area of Wuhan by identifying and extracting ecological sources and ecological corridors, followed by an ecological sensitivity assessment, minimum cumulative resistance model and buffer analysis, in order to construct and optimize ecological security patterns. The optimization for the construction of the most suitable ecological security patterns relies on social equity aspects, including the quality of urban ecological services and the improvement of the well-being of urban residents. The results demonstrate: (1) There are 19 ecological sources in Wuhan and 51 ecological corridors with a total length of 840.10 km. (2) To cater for the optimization of social equity needs, it was necessary to add one additional amendment source, with an area of 14.89 km2, and 25 new amendment corridors with a total length of 287.8 km. (3) Optimizing the ecological security patterns in Wuhan is possible through the derivation of an ecological restoration area, ecological improvement area, ecological control area and ecological shield area. The results indicate the feasibility of simultaneously protecting urban ecological security and realizing social equity.

Land degradation poses significant threats to the sustainability of ecosystem structures, functions, and services, leading to increasing ecological risks. However, integrative assessment of the ecological risk driven by land degradation remains a challenge. In this study, we established a methodological framework for assessing regional ecological risk by integrating degenerative land use transitions with multiple ecological indicators. Specifically, 11 degradation modes of land use transitions and 7 indicators on ecosystem structures, functions, and services are quantitatively integrated using remote sensing data from 2000 to 2020 in the Qinghai-Tibet Plateau of China. Results revealed that the comprehensive ecological risk of the plateau is higher in the southern and northern regions. Furthermore, we found that land development from forests towards cropland and degradation towards grasslands lead to higher ecological risks than grassland development and degradation. The ecological risk tends to show a significant distance decay pattern around the patches with land degradation. Our research framework provides an efficient, explicit, and transferable means of exploring spatiotemporal changes in ecological risk caused by degenerative land use transitions at the regional scale. It presents a constructive tool for facilitating regional-scale land use and ecosystem management planning and assessment.

China’s urbanization process is accompanied by land use and cover change (LUCC), influencing variations of air pollutants at multiple spatial scales. Monitoring the spatiotemporal variations of air pollutants and their relationship with land cover (LC) is vital for understanding the mechanisms of land-air interaction and guiding environmental management. In this study, both statistical and geo-statistical analysis is used to investigate the relationship between spatiotemporal variations of air pollutants and LC composition in the vicinity of China’s three major urban agglomerations (UAs), including Jing-Jin-Ji (JJJ), Yangtze River Delta Region (YRD), and Guangdong-Hong Kong-Macau Greater Bay Area (GBA). Results show that the spatial variations of six criteria air pollutants intra-region are large, even greater than inter-region and inter-season differences. Partial correlation analysis shows that although the impervious surface is the main driving force in elevating air pollution on a local scale, cropland is more important in elevating air pollutant levels at a regional scale. Besides that, the relationship between air pollutant levels and LC demonstrates varied seasonal and regional characteristics for different air pollutants. Our analysis provides a comprehensive understanding of the relationship between air pollutant levels and LC composition, emphasizing the impact of LC at different spatial scales.

As the basic unit of residents' living conditions, the programs and research into public facilities around a community are conducive to people's livelihood and social harmony. In this paper, Dalian, one of the livable cities in China, is selected for this research: (1) due to its unique geographical location and topographic features, the spatial distribution of the quality of living for residents in the main urban area is uneven, communities with residents with a high quality of life in Dalian are distributed in flat and developed areas around the major transportation routes, (2) the urban population of Dalian is increasing every year and community construction remains around the high-quality community that is near the traffic trunk line. Meanwhile, the proportion of the number of high-quality communities is: Xigang>Shahekou>Zhongshan>Ganjingzi; (3) the historical development of coastal cities affects the spatial layout of traffic, functional areas, and population in the region, as well as future planning and development. The types of public facilities in the traditional residential areas are complete and serve the residents. The spatial distribution of residents with a high quality of life is centered around this area, which decreases gradually outward. This paper will make a preliminary small-scale and targeted exploration of the quality of living of residents in the main urban area of Dalian and will combine the experience from the construction of public facilities for social equity in China and abroad to improve the construction of public resource materials that are needed by residents in urban areas, which will provide a foundation for research into improving the urban living quality and spatial equity. [ABSTRACT FROM AUTHOR]

Introduction: China has been experiencing dramatic urbanization in parallel with its economic boom over the past three to four decades. The Yangtze River Delta (YRD), as the most important engine in the Chinese economy, has pioneered in the rapid urbanization road of China since the late 1970s. We quantified and compared the spatiotemporal patterns of urban expansion in six major cities in the YRD urban agglomeration between 1980 and 2015. Outcomes: We found that Shanghai, Nanjing, Hangzhou, Wuxi, Suzhou and Ningbo expanded by an annual rate of 5.4%, 5.9%, 9.6%, 7.4%, 6.3% and 8.1% from 1980 to 2015, suggesting larger cities generally possess lower growth rates. Spatiotemporal patterns of urban expansion are defined by multiple forces including physical conditions and urban planning and policy. The urbanization processes in Shanghai, Nanjing and Hangzhou generally conformed with the diffusion-coalescence theory as the number of patches (NP) and patch density (PD) of urbanized land peaked and the proportion of leapfrogging urban growth type began to decrease around 2005, which separating their urbanization processes into diffusion phase before and coalescence phase after. In contrast, Suzhou, Wuxi and Ningbo is either in the diffusion or in the transition phase from diffusion to coalescence, not showing temporal dynamics of diffusion-coalescence phase across the study period, which might be related to the fact that the urban areas in these three cities were more dispersive in space than that of other cities. Conclusions: These spatially explicit findings are the fundamental cornerstone to understand the characteristics, drivers and consequences of urban expansion in the urban agglomerations, and then detect the feasibility of general urbanization theories and further advance in-depth theoretical understanding to support a sustainable urban future.

Background: The Sustainable Development Goal (SDG) three emphasizes the need to improve maternal and newborn health, and reduce global maternal mortality ratio to less than 70 per 100 000 live births by 2030. Achieving the SDG goal 3.1 target will require evidence based data on concealed inequities in the distribution of maternal and child health outcomes and their linkage to healthcare access. The objectives of this study were to estimate the number of women of reproductive age, pregnancies and live births at subnational level using high resolution maps and to quantify the number of pregnancies within user-defined distances or travel times of a health facility in three poor resource West African countries: Mali, Guinea and Liberia. Methods: The maternal and newborn health outcomes were estimated and mapped for the purpose of visualization using geospatial analytic tools. Buffer analysis was then performed to assess the proximity of pregnancies to health facilities with the aim of identifying pregnancies with inadequate access (beyond 50km) to a health facility. Results: Results showed wide variations in the distribution of maternal and newborn health outcomes across the countries of interest and districts of each of the countries. There was also clustering of health outcomes and health facilities at the urban capital cities of Bamako, Conakry, and Greater Monrovia. Conclusion: To bridge the gap in inequity in healthcare access, and improve maternal and newborn health in the study countries, there is need for equitable distribution of human resources and infrastructure within and across the various districts. [ABSTRACT FROM AUTHOR]

Urban parks have been proven to cool the surrounding environment, and can thus mitigate the urban heat island to an extent by forming a park cooling island. However, a comprehensive understanding of the mechanism of park cooling islands is still required. Therefore, we studied 32 urban parks in Jinan, China and proposed absolute and relative indicators to depict the detailed features of the park cooling island. High-spatial-resolution GF-2 images were used to obtain the land cover of parks, and Landsat 8 TIR images were used to examine the thermal environment by applying buffer analysis. Linear statistical models were developed to explore the relationships between park characteristics and the park cooling island. The results showed that the average land surface temperature (LST) of urban parks was approximately 3.6 °C lower than that of the study area, with the largest temperature difference of 7.84 °C occurring during summer daytime, while the average park cooling area was approximately 120.68 ha. The park cooling island could be classified into four categories—regular, declined, increased, and others—based on the changing features of the surrounding LSTs. Park area (PA), park perimeter (PP), water area proportion (WAP), and park shape index (PSI) were significantly negatively correlated with the park LST. We also found that WAP, PP, and greenness (characterized by the normalized difference vegetation index (NDVI)) were three important factors that determined the park cooling island. However, the relationship between PA and the park cooling island was complex, as the results indicated that only parks larger than a threshold size (20 ha in our study) would provide a larger cooling effect with the increase in park size. In this case, increasing the NDVI of the parks by planting more vegetation would be a more sustainable and effective solution to form a stronger park cooling island.

Three-dimensional (3D) buffer analysis is among the basic functions of 3D spatial analysis, and it plays an important role in 3D geographic information systems. The rapid development of the 3D Discrete Global Grid System (DGGS) provides a new method for the 3D spatial analysis of geographic information. According to the spatial topology characteristics of the 3D DGGS and the concept of dimensionality reduction, a 3D buffer analysis method based on the spatial grid of the Earth system is proposed to solve the problem of the buffer algorithm of a space object being unsatisfactory at present. In this paper, we present a method to calculate the distance between cells based on the side length of the spherical grids according to the geometric characteristics of the grids. For the grids of a geographic object, we describe the Euclidean distance expansion algorithm and the radial elevation expansion algorithm that helped us to obtain its 3D buffer. Finally, in terms of algorithm complexity and visualization effect, compared with the traditional raster buffer algorithm, the method presented in this paper has lower complexity, an improved visualization effect, and stronger generality.

Abstract One of the main challenges in video transmission is understanding and adapting to the varying network bandwidth. The traditional approach of bandwidth estimation is not accurate as there are many factors like congestion that can delay the arrival rate of the ping packet which may lead to a misconception that the bandwidth was low. Thus, the better approach to this problem will be to estimate the link conditions based on the buffer fullness. In this paper, a new system to support streaming of live and stored video through wireless network is proposed which is based on adaptive playback buffer management on the top of HTTP at the client. The buffer fullness is treated as a direct state variable that reflects the fluctuation of the network bandwidth. The buffer fullness estimation predicts the buffer status at a point in the future based on observations of the buffer over a stipulated period of time. The proposed algorithm uses non-linear exponential non-parametric regression for computing the decision parameter. A feedback message is then sent to the server in order to change the quality of the video stream for smoother video play at the client side. The synchronized update and feedback between the server and clients is achieved using HTTP protocol. During the experimentation with live video streaming, the proposed algorithm shows an improvement of 24.48% in average peak signal-to-noise ratio and 6.63% in average structural similarity index against the buffer underflow probability algorithm.

Previous studies have provided valuable insights into the impact of green space (GS) on land surface temperature (LST). However, there is a need for in-depth comparative research on changing landscape patterns in cities and their effects on the urban thermal environment. This study investigates the spatial arrangement of GS and the influence of impervious surfaces on LST in urban areas, examining their cooling and warming effects in the urban landscapes of Beijing and Islamabad. The study aims to assess the impact of the spatial arrangement of GS on LST using a moving window of 1 km 2 to analyze the overall effect of landscape patterns on the urban environment. Using Gaofen (GF-2) and Landsat-8 satellite data, we examined the biophysical surface properties of core urban areas. The results indicate a significant difference in the mean LST of 5.44 °C and 3.31 °C between impervious surfaces and GS in Beijing and Islamabad, respectively. The barren land and GS in Islamabad experience a higher LST of 3.39 °C compared to Beijing, which accounts for 1.39 °C. In Beijing, configuration metrics show no significant effect on urban LST, while edge density (ED) exhibits a slightly negative trend. In contrast, in the city of Islamabad, the landscape shape index (LSI), patch density (PD), and number of patches (NP) metrics have a significant influence on LST. The cooling effect of GS patches (0.1-0.5 ha) is more pronounced, while that of GS patches of 15-20 ha shows no significant effect on LST. The temperature difference (TD) of 5.01 °C was observed from the edge of GS in Beijing and 3.3 °C in Islamabad. Considering Islamabad's lush green scape compared to Beijing, this study suggests that Islamabad may experience an increase in LST in the future due to urbanization. This study's findings may assist urban policy-makers in designing sustainable green city layouts that effectively address future planning considerations., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

In order to reveal the processes and mechanisms of roads on land use and landscape pattern changes in arid and semi-arid regions, this paper selects the Manas River Basin as the study area, and selects different level roads in this basin in 1976 as the research object. Based on land use classification data covering 1976 and 2015, the method of buffer analysis, combined with land use dynamics, land use comprehensive indexes and landscape indexes, was used to examine the changes of land use and landscape pattern on the road buffer and buffer gradient of all levels in the past 40 years. The results show that the roads of the Manas River Basin have a significant impact on the land use change in recent 40 years and there is a gradient effect: the farther away from the road, the smaller the disturbance of the roads of all levels; the degree of impact of various grades of roads on the overall land use change show that: highway and national roads > provincial roads and special roads > county roads and township roads. In addition, highways and national roads, provincial roads and special roads, county roads and township roads have the greatest impact on the change of forest land, water area and construction land in the buffer zone. The landscape pattern analysis shows that the landscape fragmentation and heterogeneity have increased in different buffer zones of all levels in the past 40 years, but the landscape spread has decreased; the most intense range of the highways and national roads, provincial roads and special roads, county roads and township roads is 3600 meters, 600 meters and 300 meters, respectively, and the farther away from the road, the more the landscape shape is interfered by the road, and the shape of the landscape is more and more regular. This study could provide a reference for the planning of road networks in arid and semiarid areas and the reasonable development and allocation of land resources. [ABSTRACT FROM AUTHOR]

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Both biotic and abiotic factors can affect whether seagrass meadows establish as large, continuous features or as a mosaic of smaller patches, and these processes act across multiple spatial scales. Of these processes, sexual recruitment is considered vital for the recovery and resilience of seagrass meadows. Because numerous estuarine fauna can impact sexual recruitment by consuming seeds, it is important to understand variation in seed consumption throughout the seascape.We sought to determine how cross‐scale processes affected seed consumption of Zosteramarina, a widely distributed seagrass species. We deployed seed predation units (SPU) within patches ranging in size from 0.28 to 28.48 m2, and on unvegetated, sandy bottom. Seed consumption was analysed across patch sizes, at patch centres and edges and within the context of total seagrass cover within buffer zones surrounding SPU locations.Using structural equation modelling, we found that measured seascape parameters explained 34% of the observed variation in seed consumption. Specifically, we found that seagrass presence had the strongest effect on seed predation followed by a negative effect of patch size on seed consumption. Although there was no direct effect of percent seagrass cover (within a 4‐m buffer of the SPU) on seed predation, percent seagrass cover had a negative indirect effect through its positive correlation with patch size. However, we found that once variation due to patch size and areal cover were accounted for, seeds placed at patch interiors actually experienced greater consumption rates. We did not find similar relationships with our potential seed consumers, although our snapshot sampling likely obscured transient effects.We argue that seagrass recruitment could be affected by seed predation, which is influenced by multiple processes, including predator dispersal, behaviour and aggregation. Since seed‐based restoration is becoming more common, and the role of sexual recruitment in meadow maintenance appears to be increasingly important for seagrass resilience, our results demonstrate that for current management strategies to be successful, there is a need to better understand seed predation in seagrass‐dominated seascapes.Synthesis. Factors that influence propagule supply and recruitment success of seagrass operate and interact across multiple spatial scales, which can have implications for management. [ABSTRACT FROM AUTHOR]

The Transition towards sustainable energy systems requires phasing out fossil fuels. Hydropower is a key source of renewable energy and can contribute to reaching a 100 % low carbon-based energy system. Uncertainty remains about land cover changes due to hydropower deployment with a widespread perception of major losses in the land from inundation and associated habitat loss in the surrounding areas due to improved access and recreational use. Norway has a dominant share of hydropower generation in Europe with knowledge gaps in the associated land cover changes. We conducted one of the first retrospective analyses of land use change associated with hydropower development in Norway during the last 80 years. Using remote sensing data, we performed object-based analysis on sets of aerial images representing land systems before and after hydropower construction. We quantified the change in the land due to development of 40 hydropower schemes representing 24 % of the total Norwegian installed capacity. Our analysis revealed that 88 % of analyzed reservoirs were developed by regulating or expanding natural lakes. Vegetation growth was observed in the surrounding regions of 22 of 40 schemes, while urbanization was limited to only 0.9 % of the total surrounding area, primarily located within 400 m from reservoir's borders. Our findings provide insights into interaction between land use change and hydropower development in Norway. Our work provides a basis for further assessment of relevant environmental impacts and can be used to quantify expected land changes due to an increase in Norway's hydropower with integration into the European energy market. [Display omitted] • A Majority of the hydropower projects were in isolated mountain areas. • Most Norwegian reservoirs were developed on natural lakes. • Induced urbanization was limited to an average of 0.9 % of the surrounding land. • Influence distance was up to 400 m from reservoirs and 150 m from brook dams. • Hydropower projects have had vegetation regrowth since construction. [ABSTRACT FROM AUTHOR]

Pirate attacks are among the most important factors affecting maritime safety in recent years. In this study, big data were analyzed to extract the patterns and characteristics of piracy incidents and to reveal risk control options and recommendations for anti-piracy measures. Global and regional spatial patterns and characteristics were identified with the support of a geographic information system. In total, 3675 maritime piracy incidents from 2010 to 2022 were collected from the Piracy and Armed Robbery module of the Global Integrated Shipping Information System to profile the characteristics of global piracy. To visualize and analyze the features of maritime piracy, we used three geospatial techniques: kernel density estimation (KDE), k -means clustering, and buffer analysis. These geospatial techniques were used to create a KDE map for identifying piracy-prone areas. We subdivided the incidents into several classes and analyzed the features within each class to calculate the incidents that occurred in coastal areas. The following results were obtained from the geospatial analysis. First, the results of the KDE method revealed specific regions that were particularly prone to piracy, namely the Gulf of Guinea in West Africa; the seas around East Africa and the Arabian Sea; the Malacca Strait and parts of Southeast Asia and the Bay of Bengal; and the seas around South America. Second, the distributions of maritime piracy incidents by different temporal criteria, location, and ship type were compared within different classes. In particular, we found that 79.97% of minor incidents, 43.4% of less serious incidents, 50% of serious incidents, and 30.9% of very serious incidents occurred within 40 km of the coastline. The results obtained from the study contributed to an understanding of the spatial patterns of maritime piracy and provided information useful to maritime safety organizations for enhancing shipping safety. • Piracy-prone areas were identified with the support of kernel density estimation. • The geographical characteristics of maritime piracy were analyzed based on 3675 maritime piracy incidents from 2010 to 2022. • The proportion of maritime piracy incidents within different boundaries was calculated using buffer analysis. [ABSTRACT FROM AUTHOR]

Web 2.0 enables a two-way interaction between servers and clients. GPS receivers become available to more citizens and are commonly found in vehicles and smart phones, enabling individuals to record and share their trajectory data on the Internet and edit them online. OpenStreetMap (OSM) makes it possible for citizens to contribute to the acquisition of geographic information. This paper studies the use of OSM data to find newly mapped or built roads that do not exist in a reference road map and create its updated version. For this purpose, we propose a progressive buffering method for determining an optimal buffer radius to detect the new roads in the OSM data. In the next step, the detected new roads are merged into the reference road maps geometrically, topologically, and semantically. Experiments with OSM data and reference road maps over an area of 8494 km2 in the city of Wuhan, China and five of its 5 km × 5 km areas are conducted to demonstrate the feasibility and effectiveness of the method. It is shown that the OSM data can add 11.96% or a total of 2008.6 km of new roads to the reference road maps with an average precision of 96.49% and an average recall of 97.63%.

Abstract Land use and land cover (LULC) changes in oases have been a topic of great interest due to the impacts of oases on ecosystem services in arid regions. The oasis that is along the Keriya River in southern Tarim Basin, northwest China, is in an ecologically fragile region and is thus very sensitive to human interference. In this study, the spatial and temporal changes in LULC in the middle reaches of the river were quantified and assessed by using GIS technology based on remote sensing images from 1995, 2005 and 2015. The results indicated that cropland expansion and grassland degradation were the dominant LULC changes, especially in the last decade. Throughout the study period, cropland areas increased by 6.51%, while grassland areas decreased by 30.98%. A buffer analysis along the main river channel was conducted to analyze the spatial LULC characteristics. The results showed that water areas, croplands and forests were predominantly distributed along the river (in the 0–10 km buffer). The majority of mid-density grasslands and low-density grasslands were distributed in the 10–20 km buffer, and high-density grasslands were mainly distributed in the 20–30 km buffer. The conversion rates in different buffers indicated that cropland expansion primarily occurred along the river, and grassland degradation was noted in the 10–30 km buffer. Landscape pattern changes were also analyzed to account for the structural LULC characteristics. The results that were deduced from the landscape pattern change analysis showed that the patch structures of forestland and cropland increased, and increasing fragmentation tendencies were found in the other LULC types. Moreover, a model was introduced to quantify the directions of LULC changes, and the results showed that the direction of LULC change in the oasis was declining, which represents an undesirable change in LULC. Socio-economic changes were also analyzed to explain the LULC changes. The results of this study contribute to the future management of the LULC in the oasis and the protection of the Keriya River ecosystem. Highlights • Cropland expansion and grassland degradation were the dominant changes. • Changes were spatially arranged along the distance from the river channel. • Cropland expansion was intensive along the river. • Grassland degradation primarily occurred at oasis-desert ecotone. • The comprehensive ecosystem function had declined from 1995 to 2015. [ABSTRACT FROM AUTHOR]

This paper used data on land use, normalized difference vegetation index, digital elevation model, temperature and precipitation, and urban distribution to analyse the impacts of climate change, urban expansion and the Grain for Green project implementation on land use and land cover change in the Loess Plateau between 1980 and 2015 based on a single factor and comprehensive factor analysis. The aim of this paper is to explore the spatial expression of human activities under the influence of urban expansion, climate change, and the implementation of the Grain for Green project. The results indicated that climate change dominated among the influencing factors of land use and land cover change in the Loess Plateau, accounting for 93.65% of the total, with a surface-like distribution. It was followed by urban expansion, accounting for 5.46% of the total, with a point-like distribution. The impact of the Grain for Green project implementation accounted for 0.64%, with a patchy distribution. However, due to the low resolution, the quantitative assessment results regarding the role of the Grain for Green project implementation was lower, while for climate change and urban expansion, results were higher. [ABSTRACT FROM AUTHOR]

Introduction: China has been experiencing dramatic urbanization in parallel with its economic boom over the past three to four decades. The Yangtze River Delta (YRD), as the most important engine in the Chinese economy, has pioneered in the rapid urbanization road of China since the late 1970s. We quantified and compared the spatiotemporal patterns of urban expansion in six major cities in the YRD urban agglomeration between 1980 and 2015. Outcomes: We found that Shanghai, Nanjing, Hangzhou, Wuxi, Suzhou and Ningbo expanded by an annual rate of 5.4%, 5.9%, 9.6%, 7.4%, 6.3% and 8.1% from 1980 to 2015, suggesting larger cities generally possess lower growth rates. Spatiotemporal patterns of urban expansion are defined by multiple forces including physical conditions and urban planning and policy. The urbanization processes in Shanghai, Nanjing and Hangzhou generally conformed with the diffusion-coalescence theory as the number of patches (NP) and patch density (PD) of urbanized land peaked and the proportion of leapfrogging urban growth type began to decrease around 2005, which separating their urbanization processes into diffusion phase before and coalescence phase after. In contrast, Suzhou, Wuxi and Ningbo is either in the diffusion or in the transition phase from diffusion to coalescence, not showing temporal dynamics of diffusion-coalescence phase across the study period, which might be related to the fact that the urban areas in these three cities were more dispersive in space than that of other cities. Conclusions: These spatially explicit findings are the fundamental cornerstone to understand the characteristics, drivers and consequences of urban expansion in the urban agglomerations, and then detect the feasibility of general urbanization theories and further advance in-depth theoretical understanding to support a sustainable urban future. [ABSTRACT FROM AUTHOR]

The buffer generation algorithm is a fundamental function in GIS, identifying areas of a given distance surrounding geographic features. Past research largely focused on buffer generation algorithms generated in a stand-alone environment. Moreover, dissolved buffer generation is dataand computing-intensive. In this scenario, the improvement in the stand-alone environment is limited when considering large-scale mass vector data. Nevertheless, recent parallel dissolved vector buffer algorithms suffer from scalability problems, leaving room for further optimization. At present, the prevailing in-memory cluster-computing framework--Spark--provides promising efficiency for computing-intensive analysis; however, it has seldom been researched for buffer analysis. On this basis, we propose a cluster-computing-oriented parallel dissolved vector buffer generating algorithm, called the HPBM, that contains a Hilbert-space-filling-curve-based data partition method, a data skew and cross-boundary objects processing strategy, and a depth-given tree-like merging method. Experiments are conducted in both stand-alone and cluster environments using real-world vector data that include points and roads. Compared with some existing parallel buffer algorithms, as well as various popular GIS software, the HPBM achieves a performance gain of more than 50%. [ABSTRACT FROM AUTHOR]