scholarly journals Evaluating the Street Greening with the Multiview Data Fusion

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Lishuang Sun ◽  
Jianing Wang ◽  
Zhiwei Xie ◽  
Ruren Li ◽  
Xinyu Wu ◽  
...  
Keyword(s):  
Southern China ◽  
Research Area ◽  
Vegetation Coverage ◽  
Research Experience ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Street View ◽  
Shenzhen City ◽  
Green Walls ◽  
Sentinel 2

Street greening, an indispensable element of urban green spaces, has played an important role in beautifying the environment, alleviating the urban heat island effect, and improving residents’ comfort. Vegetation coverage is a common index used for measuring street greening. However, there are some shortcomings in the traditional evaluation methods of vegetation coverage. Part of the vegetation coverage cannot be determined from a two-dimensional perspective, such as shrubs and green walls. In this paper, the Sentinel-2 image was used to extract the street fractional vegetation cover (SFVC) and the Baidu street view panoramas were used to extract the green view index (GVI). To overcome the lack of a single perspective from the street vegetation coverage evaluation, the above two indices were merged to construct a comprehensive street greening evaluation index (CSGEI). The research area is the Longhua District of Shenzhen city in Southern China. All three indices were divided into five classes using natural breakpoint methods based on previous research experience. The results showed that Baidu street view panoramas could effectively identify shrubs and green walls that were deficient in the Sentinel-2 image. The GVI is a supplement to the street vegetation coverage. The SFVC and GVI were divided into five classes, from L1 to L5 implying a gradual increase in the percentage of the vegetated area. The result has shown that the SFVC was in the L1, accounting for 53.68%. After index merging, the process of accounting for the L1 decreased to 31.29%. The multiperspective integrated CSGEI could comprehensively measure the distribution information of street greening and guide the planning and management of urban green landscapes.

scholarly journals Mapping Public Urban Green Spaces Based on OpenStreetMap and Sentinel-2 Imagery Using Belief Functions

2021 ◽  
Vol 10 (4) ◽  
pp. 251
Author(s):  
Christina Ludwig ◽  
Robert Hecht ◽  
Sven Lautenbach ◽  
Martin Schorcht ◽  
Alexander Zipf
Keyword(s):  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Open Data ◽  
Green Spaces ◽  
Data Sets ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Urban Quality Of Life ◽  
Shafer Theory ◽  
Sentinel 2

Public urban green spaces are important for the urban quality of life. Still, comprehensive open data sets on urban green spaces are not available for most cities. As open and globally available data sets, the potential of Sentinel-2 satellite imagery and OpenStreetMap (OSM) data for urban green space mapping is high but limited due to their respective uncertainties. Sentinel-2 imagery cannot distinguish public from private green spaces and its spatial resolution of 10 m fails to capture fine-grained urban structures, while in OSM green spaces are not mapped consistently and with the same level of completeness everywhere. To address these limitations, we propose to fuse these data sets under explicit consideration of their uncertainties. The Sentinel-2 derived Normalized Difference Vegetation Index was fused with OSM data using the Dempster–Shafer theory to enhance the detection of small vegetated areas. The distinction between public and private green spaces was achieved using a Bayesian hierarchical model and OSM data. The analysis was performed based on land use parcels derived from OSM data and tested for the city of Dresden, Germany. The overall accuracy of the final map of public urban green spaces was 95% and was mainly influenced by the uncertainty of the public accessibility model.

scholarly journals Evaluating Greenery around Streets Using Baidu Panoramic Street View Images and the Panoramic Green View Index

Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1109 ◽  
Author(s):  
Xu Chen ◽  
Qingyan Meng ◽  
Die Hu ◽  
Linlin Zhang ◽  
Jian Yang
Keyword(s):  
Back Propagation ◽  
Application Programming Interface ◽  
Total Sample ◽  
Green Spaces ◽  
Sampling Point ◽  
Physical And Mental Health ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Street View ◽  
Panoramic Images

Urban street-side greenery, as an indispensable element of urban green spaces, is beneficial to residents’ physical and mental health. As readily available internet data, street view images have been widely used in urban green spaces research. While the relevant research using multiple images from different directions at a sampling point, researchers need to calculate the index of visible vegetation cover for many times. However, one Baidu panoramic street view image can cover the 360° view similar to that of a pedestrian. In this study, we selected 9644 points at 50-m intervals along the street lines in the central district of Sanya city, China, and acquired panoramic images via the Baidu application programming interface (API). The sky pixels were detected within the Baidu panoramic street view images using a proposed reflectance indicator. The green vegetation was extracted according to the Back Propagation (BP) neural-network method. Our proposed method was validated by comparing the results of the manual recognition and PSPNet method, and the accuracy met the requirements of the study. The Panoramic Green View Index (PGVI) was proposed to quantitatively evaluate greenery around streets. The authors found that the highest frequency value in the distribution was 0.075, which accounted for 32% of the total sample points, and the average PGVI value in this study area was low; the PGVI values between different roads varied greatly, and primary roads tended to have higher PGVI values than other roads. This case study proved that the PGVI is well suited for evaluating greenery around streets. We suggest that the PGVI derived from Baidu panoramic street view images may be a useful tool for city managers to support urban green spaces planning and management.

scholarly journals Assessment of Change in Urban Green Spaces Using Sentinel 2 MSI Data and GIS Techniques: A Case Study in Thanh Hoa City, Vietnam

2021 ◽  
Vol 1 (2) ◽  
Author(s):  
Viet Nghia NGUYEN ◽  
Le Hung TRINH ◽  
Thi Thu Nga NGUYEN ◽  
Thi Le LE
Keyword(s):  
Green Space ◽  
Urban Green Space ◽  
Green Spaces ◽  
High Quality ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Very High ◽  
Sentinel 2

This paper presents the results of an assessment of change in urban green spaces in Thanh Hoacity (Vietnam). Sentinel 2 MSI data in 2015 and 2021 are used to calculate 3 parameters: percentage ofgreen, weight of green types, and weight of proximity to green. These parameters are used to calculate theWeighted Urban Green Space Index (WUGSI). The final result shows the distribution of green space inthe study area consisted of very high-quality green, high-quality green, moderate quality green, and lowquality green. The obtained results show that the quality of urban green space in Thanh Hoa city haschanged significantly in the period 2015-2021, in which the area with category “low quality green space”increased from 7.17% up to 9.48%; areas with category “very high-quality green space” reduced from65.02% to 47.39%.

scholarly journals The Socioeconomic Welfare of Urban Green Areas and Parks; A Literature Review of Available Evidence

2021 ◽  
Vol 13 (14) ◽  
pp. 7863
Author(s):  
Antonios Kolimenakis ◽  
Alexandra D. Solomou ◽  
Nikolaos Proutsos ◽  
Evangelia V. Avramidou ◽  
Evangelia Korakaki ◽  
...  
Keyword(s):  
Literature Review ◽  
Urban Policy ◽  
Green Spaces ◽  
Future Research ◽  
Natural Environments ◽  
Exclusion Criteria ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Urban Green Areas ◽  
Green Areas

Urban green areas present a lucid example for the harmonious co-existence of the artificial and natural environments best illustrated by their interdependence and interconnection in urban spaces. Urban green areas are essential for the health and wellbeing of citizens. The present study aimed to investigate those multiple benefits for citizens that arise through the existence of urban green areas, as well as important policy dimensions that should be considered when designing the expansion of urban green spaces in urban development. The study was based on a literature review to examine for available evidence on the benefit levels derived by the existence of urban green areas. An extended literature review was followed by a structured review, based on specific inclusion and exclusion criteria, which partly followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search was conducted in two databases, and a total of 1674 articles and abstracts were identified through the database searches. After removing 114 duplicates, 1560 records were initially screened based on title and abstract. Following inclusion and exclusion criteria, 14 articles were incorporated in the structured review and a total of 47 in the extended review. The extended literature review identified 33 additional articles examining aspects of benefits that did not fall under the pre-established inclusion and exclusion criteria used in the structured review, such as health benefits and other social parameters associated with urban green spaces. The selected studies were allocated in five principal groups according to study types: three of the them consisted of studies employing “willingness to pay” (WTP) methods, five were based on property values, two studies assigned monetary values, while another two assigned CO2 values, and, finally, two studies were based on qualitative criteria. The results indicated benefits to citizens and increased welfare levels gained by the existence of urban green areas. The conducted review revealed a number of findings and recommendations that could direct future research and urban policy. Those hints could assist local authorities as well as stakeholders in order to measure and assess the benefits of green spaces and urban parks and promote measures and programs to assist their further deployment.

Social inequalities in the associations between urban green spaces, self-perceived health and mortality in Brussels: Results from a census-based cohort study

2021 ◽  
Vol 70 ◽  
pp. 102603
Author(s):  
Lucía Rodriguez-Loureiro ◽  
Lidia Casas ◽  
Mariska Bauwelinck ◽  
Wouter Lefebvre ◽  
Charlotte Vanpoucke ◽  
...  
Keyword(s):  
Cohort Study ◽  
Social Inequalities ◽  
Perceived Health ◽  
Green Spaces ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Health And Mortality
Sign in / Sign up

Export Citation Format

Share Document