scholarly journals Green Space Optimization Strategy to Prevent Urban Flood Risk in the City Centre of Wuhan

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1517
Author(s):  
Yajing Liu ◽  
Yan Zhou ◽  
Jianing Yu ◽  
Pengcheng Li ◽  
Liuqi Yang
Keyword(s):  
Urban Areas ◽  
Green Space ◽  
Simulation Experiment ◽  
City Centre ◽  
Optimization Strategy ◽  
Rainfall Runoff ◽  
Urban Flood ◽  
Flood Risks ◽  
Runoff Volume ◽  
Rainwater Runoff

Changing the water permeability ratio of urban underlying surface helps alleviate urban flood. This paper designs the swale identification experiment to modify the flood-submerging simulation experiment based on the SCS-CN model and proves that the results generated by the modified experiment better reflect the realities. The modified flood-submerging simulation experiment is then applied to downtown Wuhan to obtain the quantitative data. The data are used to quantify the catchment capacities of the lots. Based on the rainfall collection capacities, the maximum surface rainfall runoff volume that would not cause flood is arrived at using the rainfall runoff formula. The maximum runoff volume represents the rainwater storage capacities of the lot based on the proportion of the green space that is identified within the study area. The results suggest that this rainwater storage capacity evaluation model works efficiently to identify the urban areas with flood risks and provides the rainwater runoff thresholds for different areas. Adjustments in the spatial patterns and proportions of the green space help ensure that the rainwater runoff volume is below the thresholds, thus contributing to the prevention and control of the urban flood risks.

scholarly journals Green Spaces in Residential Areas of Dar es Salaam City: Types, Coverage and Uses

2021 ◽  
Vol 14 (3) ◽  
pp. 121
Author(s):  
Nicholaus Mwageni ◽  
Robert Kiunsi
Keyword(s):  
Urban Areas ◽  
Green Space ◽  
Dar Es Salaam ◽  
Economic Benefits ◽  
Natural Vegetation ◽  
Green Spaces ◽  
City Centre ◽  
Building Density ◽  
Dar Es Salaam City ◽  
The City

Green spaces in urban areas including in Dar es Salaam City provide multiple ecological, social and economic benefits. Despite their benefits they are inadequately documented in terms types, coverage and uses. This paper attempts to provide information on types, coverage and uses of green space in Dar es Salaam City. A number of methods including literature review, interpretation of remotely sensed image, interviews, focus group discussions and questionnaires were used to document city greenery. The research findings show that residential greenery is made up of greenery found within and external to plots. The dominant green spaces external to residential plots were natural and semi natural vegetation while within plots were woody plants, plots farms vegetable and ornamental gardens. Distribution of greenery varied among the wards due to differences in building density and distance from the city centre. Natural and semi natural vegetation increased with decrease of building density and increase of distance from the city centre, while the number of plots with trees for shade increased with increase of building density. Only Kawe ward that had greenery above Tanzania space planning standards, the other three wards which are informal settlements had green space deficit. Three quarters of the households use green spaces for shade provision and cooling, two thirds as a source of food products and a quarter for recreation and aesthetic purposes. The study reveals that Dar es Salaam City residents invest predominantly on shade trees in their residential plots compared to other green space types.

scholarly journals Male and female bats differ in their use of a large urban park

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Krista J Patriquin ◽  
Cylita Guy ◽  
Joshua Hinds ◽  
John M Ratcliffe
Keyword(s):  
Urban Areas ◽  
Green Space ◽  
Prey Availability ◽  
Radio Telemetry ◽  
Demographic Data ◽  
Urban Environments ◽  
City Centre ◽  
Adult Males ◽  
Urban Green ◽  
Urban Green Spaces

Abstract Understanding how wildlife respond to ever-encroaching urbanization is of great concern. Bats are the second-most speciose mammalian order and while many appear to be urban adapted, we currently have a limited understanding of their demography and habitat use within urban environments. Using a combination of captures to obtain demographic data, radio-telemetry to examine foraging and roosting behaviour, and data on diet and prey availability, we examined how big brown bats (Eptesicus fuscus), a synurbic species, use an urban green space (High Park) in Canada’s largest city centre, Toronto. We found that adult males outnumbered adult females more than two to one and that males were found throughout the park, while females were concentrated in an area with greater access to water, but lower prey availability. We also found that bats of both sexes were in poorer body condition than reported for other non-urban areas, including a site within southern Ontario. Our data suggest that High Park may not provide adequate resources for reproductive females as they were never found roosting in the park and beetles, their preferred prey, were limited. Although previous studies suggest urban green spaces may offer refuge to bats, most have not considered sex-specific responses to urbanization as they have largely been based on acoustic surveys. Our study therefore highlights the importance of considering demographic differences in response to urbanization to better inform urban management plans and green space development.

scholarly journals ANALISA TAMAN ATAP DALAM UPAYA MENGURANGI LIMPASAN AIR HUJAN PADA BANGUNAN PERKOTAAN

Kilat ◽  
2018 ◽  
Vol 6 (2) ◽  
pp. 81-87
Author(s):  
Redaksi Tim Jurnal
Keyword(s):  
Urban Areas ◽  
Public Awareness ◽  
Green Roof ◽  
Urban Housing ◽  
Runoff Volume ◽  
Runoff Decrease ◽  
Rainwater Runoff ◽  
Rainwater Management ◽  
The City ◽  
Roof Garden

With the increasing public awareness of the human relations system with the surrounding environment, communities are beginning to shift towards better sources and methods to help improve the environment. One of the methods that began to be utilized is the application of green roof construction. There are many benefits for installing a green roof whether it is in a home or office building. The study was conducted on applicable green roof construction, the benefits of installing a green roof and a process run for a green roof installation with a construction approach applicable to urban housing buildings in Jakarta and on cost analysis on material requirements and installation. And in its efforts to reduce rainwater runoff. Green roof as one in the management of rainwater in urban areas. From the result of the research resulted the calculation on survey location percentage of runoff decrease 26%. While in the test object / mock-up there is a reduction of 95% runoff volume. It can be concluded that the use of a green roof / roof garden can reduce the runoff volume produced by rainwater, resulting in reduced surface runoff automatically reduced. This will also reduce the drainage-drainage burden of the city in accommodating water. The Roof Garden plays a role in the management of rainwater management to cope with puddles up to the danger of flooding

scholarly journals Evolution of Green Areas in Europe—A Comparison Between Three Urban Areas

Proceedings ◽  
2019 ◽  
Vol 30 (1) ◽  
pp. 15
Author(s):  
Halbac-Cotoara-Zamfir ◽  
Halbac-Cotoara-Zamfir ◽  
Kalantari ◽  
Ferreira
Keyword(s):  
Urban Development ◽  
Green Infrastructure ◽  
Urban Areas ◽  
Green Space ◽  
Negative Impact ◽  
Life Quality ◽  
City Centre ◽  
Human Society ◽  
Green Areas ◽  
Architecture And Design

Urbanization is a continuous and dynamic process which has a direct impact on ecosystems and their services provided to human society. Restriction of green areas greatly accentuates urban ecological risks, having an immediate negative impact on their viability and sustainability, on life quality and population health. Increasing population density in urban areas leads to an increasing need for space. Parallel to the tentacular development of urban agglomerations, structure, architecture and design have changed, at the expense of green spaces. The development of urban areas in several European Countries (e.g., Romania, Portugal, Sweden, amid substantial demographic growth, it was made at the expense of green areas. Historical milestones of urban and peri-urban development are also key milestones in green space strategies, both in terms of development and conversion into different land-uses. This article investigates the evolution of green infrastructure in three distinct countries in Europe. In western Romania (Timisoara urban area and its neighboring peri-urban zones) we investigate the strong correlation with the evolution of urban development and the strategies developed for improving the life quality. In central Portugal, we analyze the dynamics of green infrastructures in a peri-urban catchment close to Coimbra city Centre, driven by long term urbanization. In Sweden (Malmö city), we study the history of blue-green infrastructures such as sustainable urban drainage over the past two decades and application of this in the physical planning. We will emphasize the main key milestones in green space strategies, similitudes and differences between three urban areas located in three different bio-geographical areas.

scholarly journals Utilization of Storm Water Management Model for Urban Flood Scenario

2019 ◽  
Vol 9 (2) ◽  
pp. 3716-3721
Keyword(s):  
Urban Areas ◽  
Storm Water ◽  
Rainfall Runoff ◽  
Urban Floods ◽  
Urban Flood ◽  
Rainfall Events ◽  
Storm Water Management Model ◽  
Flood Volume ◽  
Present Study Area ◽  
Prolonged Duration

Majors cities in India have witnessed huge floods from past few decades. Due to rapid population growth and improper urban planning the chances of creek, localised or flash urban floods have drastically increased. Climatic changes are also a key reason for heavy rainfall that increases the flood volume and depth in a catchment. Modelling of Storm water plays a key role in estimating flood runoff quantity and quality. To check these issues SWMM is used to simulate floods scenario in Urban areas. This hydrological study is carried out to simulate and understand the rainfall runoff characteristics of the study area by using SWMM. It is an effective tool used for simulating flash floods and runoff in urban areas. In this study catchments have been subdivided into 14 parts and modelled for year 2017 rainfall events of 1-hr interval. The present study area is evaluated by importing AutoCAD map of the area in SWMM. Further Rainfall Data is imported as time series in the model. The results depict that the Runoff for the Sub catchments of S1, S2, S3, S9, S13 blocks are maximum. The study states that no nodes are flooded and also no overflow sections. Thus, the selected study area storm network system has been well planned and has enough carrying capacity to carry the simulated rainfall for a prolonged duration

scholarly journals POTENSI REDUKSI LIMPASAN PERMUKAAN DENGAN METODE SOIL CONSERVATION SERVICE - CURVE NUMBER DI KELURAHAN RAWA BUNTU

2021 ◽  
Vol 1 (2) ◽  
pp. 51
Author(s):  
Steffany Trifena ◽  
Dwi Prabowo
Keyword(s):  
Soil Conservation ◽  
Green Space ◽  
Curve Number ◽  
Soil Conservation Service ◽  
Rainfall Runoff ◽  
Total Rainfall ◽  
Runoff Reduction ◽  
Rainwater Runoff ◽  
Service Curve

<em><span lang="EN-US">Development in Rawa Buntu Subdistrict caused land use change and made green space  area  in  Rawa  Buntu  Subdistrict  decreased,  so  it  could  cause  flood.  This research  was  conducted  to  know  the  potential  of  rainwater  runoff  reduction  in each type of land cover in Rawa Buntu Subdistrict to serve as the basis for better planning in the future. The Soil Conservation Service - Curve Number (SCS-CN) method  is  used  to  calculate  the  total  rainfall  runoff  that  can  be  reduced  and  to know  the  role  of  green  space  in  reducing  rainwater  runoff.  The  result  of  the research shows that residential area dominates Rawa Buntu Subdistrict about 65% and  green  space  is  only  about  18%.  The  volume  of  rainfall  runoff  that  can  be reduced  each  month  on  AMC  I,  AMC  II  and  AMC  III  is  74,4MGal,  37,8MGal and  17,9MGal  with  green  space  contribution  of  27%,  31,2%  and  36,4%  of  the total rainfall runoff that can be reduced for each AMC condition.</span></em>

scholarly journals Modelling Infiltration Process, Overland Flow and Sewer System Interactions for Urban Flood Mitigation

Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2028
Author(s):  
Carlos Martínez ◽  
Zoran Vojinovic ◽  
Roland Price ◽  
Arlex Sanchez
Keyword(s):  
Urban Areas ◽  
Overland Flow ◽  
Surface Flow ◽  
Rainfall Runoff ◽  
Coupled Models ◽  
Infiltration Process ◽  
Urban Flood ◽  
Practical Applications ◽  
Urban Catchments ◽  
2D Model

Rainfall-runoff transformation on urban catchments involves physical processes governing runoff production in urban areas (e.g., interception, evaporation, depression, infiltration). Some previous 1D/2D coupled models do not include these processes. Adequate representation of rainfall–runoff–infiltration within a dual drainage model is still needed for practical applications. In this paper we propose a new modelling setup which includes the rainfall–runoff–infiltration process on overland flow and its interaction with a sewer network. We first investigated the performance of an outflow hydrograph generator in a 2D model domain. The effect of infiltration losses on the overland flow was evaluated through an infiltration algorithm added in a so-called Surf-2D model. Then, the surface flow from a surcharge sewer was also investigated by coupling the Surf-2D model with the SWMM 5.1 (Storm Water Management Model). An evaluation of two approaches for representing urban floods was carried out based on two 1D/2D model interactions. Two test cases were implemented to validate the model. In general, similar results in terms of peak discharge, water depths and infiltration losses against other 1D/2D models were observed. The results from two 1D/2D model interactions show significant differences in terms of flood extent, maximum flood depths and inundation volume.

scholarly journals The green roofs for reduction in the load on rainwater drainage in highly urbanised areas

2021 ◽  
Author(s):  
Alicja Kolasa-Więcek ◽  
Dariusz Suszanowicz
Keyword(s):  
Urban Areas ◽  
Geographical Information Systems ◽  
Drainage System ◽  
Water System ◽  
Green Roofs ◽  
Geographical Information ◽  
City Centre ◽  
Rainwater Runoff ◽  
The City

AbstractRapid weather phenomena, particularly sudden and intense rainfall, have become a problem in urban areas in recent years. During heavy rainfall, urban rainwater drainage systems are unable to discharge huge amounts of runoff into collecting reservoirs, which usually results in local flooding. This paper presents attempts to forecast a reduction in the load on the rainwater drainage system through the implementation of green roofs in a case study covering two selected districts of Opole (Poland)—the Old Town and the City Centre. Model tests of extensive and intensive roofs were carried out, in order to determine the reduction of rainwater runoff from the roof surface for the site under study. The potential of the roofs of the buildings to make a green roof was also determined using geographical information systems (GIS), for a case study of two central districts of Opole. It proposed a methodology to determine the rainwater drainage system load reduction by making green roofs. The analyses carried out lead to the conclusion that, in the districts selected for the study, the execution of green roofs on 25% of the of buildings with the potential to implement this type of roof solution could reduce the load on the rain water system by a degree that protects the city area from local flooding.

scholarly journals Evaluation of the Equity and Regional Management of Some Urban Green Space Ecosystem Services: A Case Study of Main Urban Area of Xi’an City

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 813
Author(s):  
Hui Dang ◽  
Jing Li ◽  
Yumeng Zhang ◽  
Zixiang Zhou
Keyword(s):  
Ecosystem Services ◽  
Carbon Sequestration ◽  
Urban Areas ◽  
Green Space ◽  
Well Being ◽  
Urban Green Space ◽  
Green Spaces ◽  
Deposition Flux ◽  
Urban Green ◽  
Xi’An City

Urban green spaces can provide many types of ecosystem services for residents. An imbalance in the pattern of green spaces leads to an inequality of the benefits of such spaces. Given the current situation of environmental problems and the basic geographical conditions of Xi’an City, this study evaluated and mapped four kinds of ecosystem services from the perspective of equity: biodiversity, carbon sequestration, air purification, and climate regulation. Regionalization with dynamically constrained agglomerative clustering and partitioning (REDCAP) was used to obtain the partition groups of ecosystem services. The results indicate that first, the complexity of the urban green space community is low, and the level of biodiversity needs to be improved. The dry deposition flux of particulate matter (PM2.5) decreases from north to south, and green spaces enhance the adsorption of PM2.5. Carbon sequestration in the south and east is higher than that in the north and west, respectively. The average surface temperature in green spaces is lower than that in other urban areas. Second, urban green space resources in the study area are unevenly distributed. Therefore, ecosystem services in different areas are inequitable. Finally, based on the regionalization of integrated ecosystem services, an ecosystem services cluster was developed. This included 913 grid spaces, 12 partitions, and 5 clusters, which can provide a reference for distinct levels of ecosystem services management. This can assist urban managers who can use these indicators of ecosystem service levels for planning and guiding the overall development pattern of green spaces. The benefits would be a maximization of the ecological functions of green spaces, an improvement of the sustainable development of the city, and an improvement of people’s well-being.

scholarly journals Socioeconomic Differences in Walking Time of Children and Adolescents to Public Green Spaces in Urban Areas—Results of the German Environmental Survey (2014–2017)

2021 ◽  
Vol 18 (5) ◽  
pp. 2326
Author(s):  
Julia Rehling ◽  
Christiane Bunge ◽  
Julia Waldhauer ◽  
André Conrad
Keyword(s):  
Young People ◽  
Children And Adolescents ◽  
Urban Areas ◽  
Green Space ◽  
Positive Impact ◽  
Green Spaces ◽  
Environmental Survey ◽  
Urban Green Spaces ◽  
Public Green Space ◽  
Walking Time

Public green spaces have a high potential for a positive impact on people’s health and wellbeing, especially in urban areas. Studies on environmental justice indicate socially unequal access possibilities to urban green spaces. This article presents results on associations between individual socioeconomic position (SEP) and walking time from home to public green spaces in young people living in urban areas with more than 20,000 inhabitants in Germany. Data were derived from the German Environmental Survey for Children and Adolescents 2014–2017 (GerES V), the environmental module of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS Wave 2). The sample comprises 1149 participants aged 3 to 17 years. A total of 51.5% of the participants reach a public green space on foot within five and 72.8% within ten minutes from home. The lower the participant’s SEP, the longer the walking time. Logistic regression models controlling for age group, sex, migration background, and region of residence show that participants with a low SEP have a significantly higher risk (odds ratio = 1.98; 95% confidence interval: 1.31–2.99) of needing more than ten minutes to walk from home to a public green space than participants with a high SEP. GerES V data indicate that young people living in urban areas in Germany do not equally benefit from the health-promoting potential of green spaces, which is an important aspect of environmental health inequalities.

Sign in / Sign up

Export Citation Format

Share Document