scholarly journals Dynamic Changes in Community Deprivation of Access to Urban Green Spaces by Multiple Transport Modes

2021 ◽  
Vol 9 ◽  
Author(s):  
Shunqi Cheng ◽  
Zhiqiang Liao ◽  
Yu Zhu
Keyword(s):  
Growth Rate ◽  
Spatial Pattern ◽  
Urban Area ◽  
Public Transport ◽  
Green Spaces ◽  
Dynamic Changes ◽  
Urban Green ◽  
Urban Green Spaces ◽  
The Core ◽  
Transport Modes

Urban green spaces (UGSs) improve the quality of life of urban inhabitants. With the acceleration of urbanization and changes in traffic networks, it remains unclear whether changes in the distribution of UGSs can satisfy the needs of all inhabitants and offer equal services to inhabitants from different socioeconomic backgrounds. This study addresses this issue by analyzing dynamic changes in UGS accessibility in 2012, 2016, and 2020 for inhabitants of the central urban area of Fuzhou in China at the community level. The study introduces multiple transportation modes for an accessibility estimation based on a framework using the two-step floating catchment area method and examines the dynamic changes in community deprivation of UGS accessibility using Kernel regularized least squares, a machine learning algorithm. The results demonstrate that spatial disparities of UGS accessibility exist among the multi-transport modes and vary with time. Communities with high accessibility to UGSs by walking are scattered around the urban area; for accessibility by cycling, the high accessibility regions expand and surround the regions with low accessibility in the core urban areas, forming a semi-enclosed spatial pattern. However, the core urban spatial orientation of UGS accessibility by public transit demonstrates a reverse trend to the above two modes. The spatial pattern of UGS accessibility also varies over time, and the growth rate of accessibility slightly declined during the study period. Furthermore, the increase in UGS accessibility tended to slow from 2016–2020 compared with 2012–2016, and the trend toward equality was also erratic. The degree of deprivation for communities first weakened and was then aggravated, corresponding to the slowdown in the growth rate of accessibility, leading to the persistence existence of social inequality. Moreover, significant deprivation mainly exists among less educated people or those using the cycling and integrated travel modes. Although public transport is developing, deprived communities, such as communities with large proportion of older people, have experienced a decline in access to UGSs by public transport. Based on these findings, the study proposes a policy framework for the balanced distribution of UGSs as part of urbanization.

scholarly journals Community-Level Urban Green Space Equity Evaluation Based on Spatial Design Network Analysis (sDNA): A Case Study of Central Wuhan, China

2021 ◽  
Vol 18 (19) ◽  
pp. 10174
Author(s):  
Qing Li ◽  
Kaili Peng ◽  
Peng Cheng
Keyword(s):  
Network Analysis ◽  
Community Level ◽  
Green Spaces ◽  
Urban Green ◽  
Urban Green Spaces ◽  
The Core ◽  
Spatial Design ◽  
Residential Population ◽  
Baseline Information ◽  
Core Areas

Urban green spaces (UGSs) provide numerous irreplaceable environmental and social benefits to humankind, but the lack of baseline information makes it difficult to propose a reasonable greening strategy so as to achieve an equitable allocation of community green spaces. This paper divides UGSs into three classes using the spatial design network analysis (sDNA) and quantifies the UGS accessibility of communities in central Wuhan. Based on these results and the Gini coefficient, we analyze the UGS equity of the spatial distribution at the community level, then propose future greening strategies both at the city and community levels. The results show that the railway station and old Wuhan city are the core areas of traffic network strength (TNS). UGSs are evenly distributed in the core areas of TNS, but the number of UGSs in non-core areas is small, and their distribution is relatively uneven, and the number of communities with medium UGS accessibility is the largest, carrying the densest residential population. Most communities perform well in terms of UGS equity, but the UGS equity of 163 communities, covering a population of more than one million, remains to be improved. The method and conclusions of this study will contribute to the future greening policy making of 965 communities in central Wuhan, thus promoting the orderly planning and high-quality construction of community living circles.

scholarly journals Rapid Mapping and Annual Dynamic Evaluation of Quality of Urban Green Spaces on Google Earth Engine

2021 ◽  
Vol 10 (10) ◽  
pp. 670
Author(s):  
Qiang Chen ◽  
Cuiping Zhong ◽  
Changfeng Jing ◽  
Yuanyuan Li ◽  
Beilei Cao ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Urban Area ◽  
Google Earth ◽  
Green Spaces ◽  
Dynamic Evaluation ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Rapid Mapping ◽  
Google Earth Engine

In order to achieve the United Nations 2030 Sustainable Development Goals (SDGs) related to green spaces, monitoring dynamic urban green spaces (UGSs) in cities around the world is crucial. Continuous dynamic UGS mapping is challenged by large computation, time consumption, and energy consumption requirements. Therefore, a fast and automated workflow is needed to produce a high-precision UGS map. In this study, we proposed an automatic workflow to produce up-to-date UGS maps using Otsu’s algorithm, a Random Forest (RF) classifier, and the migrating training samples method in the Google Earth Engine (GEE) platform. We took the central urban area of Beijing, China, as the study area to validate this method, and we rapidly obtained an annual UGS map of the central urban area of Beijing from 2016 to 2020. The accuracy assessment results showed that the average overall accuracy (OA) and kappa coefficient (KC) were 96.47% and 94.25%, respectively. Additionally, we used six indicators to measure quality and temporal changes in the UGS spatial distribution between 2016 and 2020. In particular, we evaluated the quality of UGS using the urban greenness index (UGI) and Shannon’s diversity index (SHDI) at the pixel level. The experimental results indicate the following: (1) The UGSs in the center of Beijing increased by 48.62 km2 from 2016 to 2020, and the increase was mainly focused in Chaoyang, Fengtai, and Shijingshan Districts. (2) The average proportion of relatively high and above levels (UGI > 0.5) in six districts increased by 2.71% in the study area from 2016 to 2020, and this proportion peaked at 36.04% in 2018. However, our result revealed that the increase was non-linear during this assessment period. (3) Although there was no significant increase or decrease in SHDI values in the study area, the distribution of the SHDI displayed a noticeable fluctuation in the northwest, southwest, and northeast regions of the study area between 2016 and 2020. Furthermore, we discussed and analyzed the influence of population on the spatial distribution of UGSs. We found that three of the five cold spots were located in the east and southeast of Haidian District. Therefore, the proposed workflow could provide rapid mapping and dynamic evaluation of the quality of UGS.

scholarly journals Vegetation Structure, Species Composition, and Carbon Sink Potential of Urban Green Spaces in Nagpur City, India

Land ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 107
Author(s):  
Shruti Lahoti ◽  
Ashish Lahoti ◽  
Rajendra Kumar Joshi ◽  
Osamu Saito
Keyword(s):  
Growth Rate ◽  
Species Composition ◽  
Tree Species ◽  
Carbon Stock ◽  
Species Selection ◽  
Green Spaces ◽  
Local Authorities ◽  
Urban Green ◽  
Urban Green Spaces ◽  
The City

Nagpur is rapidly urbanizing, and in the process witnessing decline in its green status which is one of the identities of the city. The study aims to understand the current species diversity, composition and structure in different classes of greens prevalent in the city. As urban green spaces (UGS) are also reservoirs of carbon stock, the study estimates their biomass. Through rigorous field work, data were collected from 246 sample plots across various UGS classes as pre-stratification. Then the biomass was estimated using non-destructive method with species-specific equation. The diversity of tree species recorded in UGS varies, with high diversity recorded in avenue plantation and institutional compounds. The overall variation in species composition among UGS classes was 36.8%. While in managed greens the species composition was similar, in institutional greens and forest it was different. Particularly, in forest the evenness was high with low diversity and low species richness. The structural distribution indicate lack of old trees in the city, with high number of tree species between diameter classes of 10–40 cm. Biomass was recorded high in road-side plantations (335 t ha−1) and playgrounds (324 t ha−1), and trees with bigger girth size where the main contributors. The dominant species indicates that high growth rate, tolerance to drought and pollution are the key attributes considered for species selection by local authorities. Though the city holds green image, vegetation along the avenues and institutions are stressed, exposed, and threatened by felling activities for grey infrastructure expansions. In such scenario, protection and preservation of older trees is crucial to maintain the carbon stock of the city. In addition, local authorities need to focus on effective afforestation programs through public participation to achieve high survival rate and reduce the maintenance cost. For species selection in addition to phenology and growth rate, tree biomass and life span needs to be considered to significantly enhance the urban environment and increase the benefits derived from UGS.

scholarly journals Challenges to the Multi-Functional Uses and Multifarious Benefits of Urban Green Spaces: Basis of Urban Biodiversity Planning and Management in the City of Manila, Philippines

2016 ◽  
Vol 1 (1) ◽  
pp. 69
Author(s):  
Leonora Gonzales ◽  
Dina Magnaye
Keyword(s):  
Growth Rate ◽  
Well Being ◽  
The Philippines ◽  
Urban Biodiversity ◽  
Capital City ◽  
Green Spaces ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Planning And Management ◽  
Biodiversity Planning

Urbanization is a global phenomenon which is projected by the United Nations to grow annually at 65 million between 2000 and 2030 in developing countries. As an archipelagic nation, the Philippines is considered as a highly urbanized nation where over three-fourths of its population is estimated to reside in urban areas, posting a proportion of one person residing in rural area for every three in urban area. The National Capital Region (NCR), the core region of the counry, registers a 100% urbanization level and where the most densely populated areas converged. It generally exhibits an urban population growth rate that exceeds the national growth rate. Manila, the capital city of the Philippines, is the second largest and the world’s most densely populated city given its small land area and huge human population. The concentration of people in this city and the urbanization processes are foreseen to create environmental stress leading to potential biodiversity losses coupled with other urban environmental occurrences such as flooding, air pollution, sea level rise, earthquake, subsidence, traffic congestion, water pollution, among others. These natural and man-made hazards pose challenge to the multi-functional uses and various benefits of urban green spaces (UGS). UGS play a significant role in enhancing the quality and resiliency of the environment as well as in improving the health and general well being of city dwellers. It is in this context that the challenges and opportunities of UGS are examined. The paper attempts to identify and determine the factors that influence UGS as basis for urban biodiversity planning and management.

Spatial pattern of urban green spaces in a long-term compact urbanization process—A case study in China

2019 ◽  
Vol 96 ◽  
pp. 111-119 ◽  
Author(s):  
Caige Sun ◽  
Tao Lin ◽  
Qianjun Zhao ◽  
Xinhu Li ◽  
Hong Ye ◽  
...  
Keyword(s):  
Spatial Pattern ◽  
Green Spaces ◽  
Urbanization Process ◽  
Urban Green ◽  
Urban Green Spaces

Wildfire spreading across the urban area: definition and mapping of vegetation connectivity

2020 ◽  
Author(s):  
Maria Polinova ◽  
Haim Kutiel ◽  
Lea Wittenberg ◽  
Anna Brook
Keyword(s):  
Urban Area ◽  
Urban Areas ◽  
Fire Management ◽  
Fire Service ◽  
Green Spaces ◽  
Landsat 8 ◽  
Ignition Point ◽  
Urban Green ◽  
Urban Green Spaces ◽  
Forest Fire Management

<p>Climate change, increased frequency of natural disasters and their anomaly in the modern world demand review existing knowledge about environment and approaches for its management. In recent decades, one of the phenomena that humanity met with is urban wildfires. Experience has shown that existing approaches from forest fire management are not effective in a built-up environment. In practice, studying this phenomenon is limited due to lack of empirical knowledge.</p><p>To bridge this knowledge gap, the fire dynamic patterns in an urban area was reconstructed based on fire service data on the example of wildfire in Haifa (Israel) in November 2016. The results of reconstruction show that unlike forest fires, where fuel is almost unlimited around the ignition point, urban areas are sensitive to wildfire because of 'fire connectivity' through vegetation: fire moves from one green patch to another, bypassing nonflammable structures.</p><p>Although the role of urban vegetation in the spread of fires is obvious, it is difficult to define a suitable term in case of fire management. Today, cities and vegetation are studied together in the urban planning and ecosystem services and have different definitions, depends on study propose: ‘Urban Green Spaces’, ‘Green Infrastructure’, ‘Urban Forestry’, etc. The closest term in fire management for vegetation interaction with structures is ‘Wildland Urban Interface’ (WUI). However, WUI considers vegetation surrounding the city and excludes urban green spaces. Since before this time the inner-city vegetation was not considered in the fire management and wasn’t estimated its essential parameters for this case, it does not have an exact term and definition. The reconstructed wildfire allows to analyze and define vegetation in context of fire connectivity.</p><p>The results show that wildfire spreads in the urban area through ember attacks. Meanwhile, the embers led to ignition only in some patches and only in a few cases the energy amount was enough for new embers emission. Thus, the fire vegetation connectivity in urban areas can be defined by its ability to ignite and reproduce new embers.</p><p>To support fire management and risk assessment in urban areas, it is important to map vegetation based on its ignitability and potential energy emission. The task is complicated due to the uncertainty of surface fuel (including both litter and human waste). Citywide, detecting and monitoring such patches through field surveys is time-consuming work. To solve this objective by remote sensing technique, we analyzed series of Landsat 8 images for 2015 to identify spectral and temporal features of vegetation related to its flammability. The proposed approach supports estimation and mapping of vegetation connectivity in case of urban wildfire based on its multi-temporal spectral signature.</p>

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