Vulnerability assessment in urban areas exposed to flood risk: methodology to explore green infrastructure benefits in a simulation scenario involving the Cañaveralejo River in Cali, Colombia

The densification of urban areas has raised concerns over increased pluvial flooding. Flood risk in urban areas might increase under the impact of land use changes. Urbanisation involves the conversion of natural areas to impermeable areas, causing lower infiltration rates and increased runoff. When high-intensity rainfall exceeds the capacity of an urban drainage system, the runoff causes pluvial flooding in low-laying areas. In the present study, a long time series (i.e., 20 years) of geo-referenced flood claims from property owners has been collected and analysed in detail to assess flood risk as it relates to land use changes in urban areas. The flood claim data come from property owners with flood insurance that covers property loss from overland flooding, groundwater intrusion through basement walls, as well as flooding from drainage systems; these data serve as a proxy of flood severity. The spatial relationships between land use change and flood occurrences in different urban areas were analysed. Special emphasis was placed on examining how nature-based solutions and blue-green infrastructure relate to flood risk. The relationships are defined by a statistical method explaining the tendencies whereby land use change affects flood risk.

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Urban Greening and Human-Wildlife Relations in Philadelphia: From Animal Control to Multispecies Coexistence?

Environmental Values ◽

10.3197/096327119x15678473650901 ◽

2020 ◽

Vol 29 (1) ◽

pp. 67-87 ◽

Cited By ~ 2

Author(s):

Christian Hunold

Keyword(s):

Public Health ◽

Green Infrastructure ◽

Urban Areas ◽

Urban Runoff ◽

Urban Wildlife ◽

Wildlife Habitat ◽

Wild Animals ◽

Urban Greening ◽

Human Needs ◽

Animal Control

City-scale urban greening is expanding wildlife habitat in previously less hospitable urban areas. Does this transformation also prompt a reckoning with the longstanding idea that cities are places intended to satisfy primarily human needs? I pose this question in the context of one of North America's most ambitious green infrastructure programmes to manage urban runoff: Philadelphia's Green City, Clean Waters. Given that the city's green infrastructure plans have little to say about wildlife, I investigate how wild animals fit into urban greening professionals' conceptions of the urban. I argue that practitioners relate to urban wildlife via three distinctive frames: 1) animal control, 2) public health and 3) biodiversity, and explore the implications of each for peaceful human-wildlife coexistence in 'greened' cities.

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Urban Vulnerability Assessment for Pandemic Surveillance—The COVID-19 Case in Bogotá, Colombia

Sustainability ◽

10.3390/su13063402 ◽

2021 ◽

Vol 13 (6) ◽

pp. 3402

Author(s):

Jeisson Prieto ◽

Rafael Malagón ◽

Jonatan Gomez ◽

Elizabeth León

Keyword(s):

Vulnerability Assessment ◽

Disease Transmission ◽

Urban Areas ◽

A Priori ◽

Vulnerability Index ◽

Past Century ◽

Vulnerability Factors ◽

Early Assessment ◽

Global Citizens ◽

Urban Vulnerability

A pandemic devastates the lives of global citizens and causes significant economic, social, and political disruption. Evidence suggests that the likelihood of pandemics has increased over the past century because of increased global travel and integration, urbanization, and changes in land use with a profound affectation of society–nature metabolism. Further, evidence concerning the urban character of the pandemic has underlined the role of cities in disease transmission. An early assessment of the severity of infection and transmissibility can help quantify the pandemic potential and prioritize surveillance to control highly vulnerable urban areas in pandemics. In this paper, an Urban Vulnerability Assessment (UVA) methodology is proposed. UVA investigates various vulnerability factors related to pandemics to assess the vulnerability in urban areas. A vulnerability index is constructed by the aggregation of multiple vulnerability factors computed on each urban area (i.e., urban density, poverty index, informal labor, transmission routes). This methodology is useful in a-priori evaluation and development of policies and programs aimed at reducing disaster risk (DRR) at different scales (i.e., addressing urban vulnerability at national, regional, and provincial scales), under diverse scenarios of resources scarcity (i.e., short and long-term actions), and for different audiences (i.e., the general public, policy-makers, international organizations). The applicability of UVA is shown by the identification of high vulnerable areas based on publicly available data where surveillance should be prioritized in the COVID-19 pandemic in Bogotá, Colombia.

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Ecological Connectivity in Agricultural Green Infrastructure: Suggested Criteria for Fine Scale Assessment and Planning

Land ◽

10.3390/land10080807 ◽

2021 ◽

Vol 10 (8) ◽

pp. 807

Author(s):

Simone Valeri ◽

Laura Zavattero ◽

Giulia Capotorti

Keyword(s):

Land Cover ◽

Green Infrastructure ◽

Rural Areas ◽

Urban Areas ◽

Landscape Heterogeneity ◽

Agricultural Landscapes ◽

Spatial Pattern Analysis ◽

Fine Scale ◽

Unique Type

In promoting biodiversity conservation and ecosystem service capacity, landscape connectivity is considered a critical feature to counteract the negative effects of fragmentation. Under a Green Infrastructure (GI) perspective, this is especially true in rural and peri-urban areas where a high degree of connectivity may be associated with the enhancement of agriculture multifunctionality and sustainability. With respect to GI planning and connectivity assessment, the role of dispersal traits of tree species is gaining increasing attention. However, little evidence is available on how to select plant species to be primarily favored, as well as on the role of landscape heterogeneity and habitat quality in driving the dispersal success. The present work is aimed at suggesting a methodological approach for addressing these knowledge gaps, at fine scales and for peri-urban agricultural landscapes, by means of a case study in the Metropolitan City of Rome. The study area was stratified into Environmental Units, each supporting a unique type of Potential Natural Vegetation (PNV), and a multi-step procedure was designed for setting priorities aimed at enhancing connectivity. First, GI components were defined based on the selection of the target species to be supported, on a fine scale land cover mapping and on the assessment of land cover type naturalness. Second, the study area was characterized by a Morphological Spatial Pattern Analysis (MSPA) and connectivity was assessed by Number of Components (NC) and functional connectivity metrics. Third, conservation and restoration measures have been prioritized and statistically validated. Notwithstanding the recognized limits, the approach proved to be functional in the considered context and at the adopted level of detail. Therefore, it could give useful methodological hints for the requalification of transitional urban–rural areas and for the achievement of related sustainable development goals in metropolitan regions.

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People’s Avoidance of Neighboring Agricultural Urban Green Infrastructure: Evidence from a Choice Experiment

Sustainability ◽

10.3390/su13126930 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6930

Author(s):

Shinsuke Kyoi

Keyword(s):

Spatial Econometrics ◽

Green Infrastructure ◽

Urban Areas ◽

Choice Experiment ◽

Online Survey ◽

Agricultural Land ◽

Residential Areas ◽

Urban Green ◽

Ishikawa Prefecture ◽

Urban Green Infrastructure

This study evaluates people’s preferences regarding the proximity of their residence to agricultural urban green infrastructure (UGI), such as agricultural land and satoyama, and discusses the availability of these types of land as UGI. UGI is vital for reducing the negative environmental impacts of urban areas, as these impacts are too large to ignore. In this study, we conducted an online survey and a choice experiment to investigate people’s perceptions regarding the proximity of their residence to agricultural UGI (AUGI). The respondents of the choice experiment were 802 inhabitants of Ishikawa Prefecture, Japan, which has rich agricultural resources. To examine explicitly the spatial autocorrelation of people’s preferences, in this study, we used the spatial econometrics method. The main empirical findings are that people prefer agricultural land far away from their residence—more than 1000 m, not within 1000 m—which reflects the not-in-my-backyard phenomenon. Meanwhile, people’s preferences regarding proximity to satoyama are complicated and their preferences are positively spatially autocorrelated. The results indicate that policymakers and urban planners should manage and provide AUGI far away from residential areas; otherwise, they must address people’s avoidance of neighboring AUGI.

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Lightweight aggregates to reduce heavy metal pollution in green infrastructure for urban stormwater management

10.5194/egusphere-egu21-7915 ◽

2021 ◽

Author(s):

Concepcion Pla ◽

Javier Valdes-Abellan ◽

Miguel Angel Pardo ◽

Maria Jose Moya-Llamas ◽

David Benavente

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Green Infrastructure ◽

Metal Pollution ◽

Heavy Metal Pollution ◽

Urban Areas ◽

Stormwater Management ◽

Lightweight Aggregates ◽

Urban Stormwater ◽

Runoff Water

The impervious nature of urban areas is mostly responsible for urban flooding, runoff water pollution and the interception of groundwater recharge. Green infrastructure and sustainable urban drainage systems combine natural and artificial measures to mitigate the abovementioned problems, improving stormwater management and simultaneously increasing the environmental values of urban areas. The actual rate of urban growth in many urban areas requires the enhancement and optimization of stormwater management infrastructures to integrate the territorial development with the natural processes. Regarding the quality of runoff stormwater, heavy metals are critical for their impact on human health and ecological systems, even more if we consider the cumulative effect that they produce on biota. Thus, innovative stormwater management approaches must consider new solutions to deal with heavy metal pollution problems caused by runoff. In this study, we propose the employment of Arlita&#174; and Filtralite&#174;, two kind of lightweight aggregates obtained from expanded clays, to remove heavy metal concentration from runoff stormwater. Laboratory experiments were developed to evaluate the removal rate of different heavy metals existent in runoff stormwater. The lightweight aggregates acted as filter materials in column experiments to quantify their removal capacity. In addition, batch tests were also developed to evaluate the exhaustive capacity of the materials. Results from the study confirmed the efficiency of the selected lightweight aggregates to reduce the heavy metals concentration by up to 90% in urban stormwater runoff.

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Dynamic evaluation of small urban green areas at local level using GEOBIA

10.5194/egusphere-egu21-10374 ◽

2021 ◽

Author(s):

Ana-Maria Popa ◽

Diana Andreea Onose ◽

Ionut Cosmin Sandric ◽

Simona Raluca Gradinaru ◽

Athanasios Alexandru Gavrilidis

Keyword(s):

Green Infrastructure ◽

Urban Areas ◽

Local Level ◽

Consumption Pattern ◽

Urbanization Process ◽

Dynamic Evaluation ◽

Urban Green ◽

Urban Green Areas ◽

Green Areas

Urban green infrastructure has various benefits known as ecosystem services such as regulating, cultural, provisioning and supporting services. Among the provided benefits there are decrease of air temperature, increasing humidity and mitigating urban heat island as regulating services; human-nature relations as cultural services; improving air quality, carbon sequestration as provisioning services and photosynthesis, nutrient and water cycling as supporting services. The high intensity of the urbanization process across the last decades coupled with weak legislative frameworks resulted both in large areas affected by urban sprawl and densification of the existing urban fabric. Both phenomenon generated loss in open spaces, especially green areas. In the context of the sustainable urbanization promoted by HABITAT Agenda, the knowledge related with the distribution, size and quality of urban green areas represents a priority. The study aim is to identify small urban green areas at local level at different time moments for a dynamic evaluation. We focused on small urban green areas since they are scarcely analysed even if their importance for the urban quality of life Is continuously increasing given the urbanization process. We used satellite imagery acquired by Planet Satellite Constellations, with a spatial resolution of 3.7 m and daily coverage, for extracting green areas. The images were processed using Geographic Object-Based Image Analysis (OBIA) techniques implemented in Esri ArcGIS Pro. The spatial analysis we performed generated information about distribution, surfaces, quality (based on NDVI) and dynamic of small urban green areas. The results are connected with the local level development of the urban areas we analysed, but also with the population consumption pattern for leisure services, housing, transport or other public utilities. The analysis can represent a complementary method for extracting green areas at urban level and can support the data collection for calculating urban sustainability indicators.

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Can management improve the lawn’s functioning in the conditions of multiple anthropogenic stressors?

10.5194/egusphere-egu21-13522 ◽

2021 ◽

Author(s):

Olga Gavrichkova ◽

Dario Liberati ◽

Viktoriya Varyushkina ◽

Kristina Ivashchenko ◽

Paolo De Angelis ◽

...

Keyword(s):

Heavy Metals ◽

Soil Respiration ◽

Green Infrastructure ◽

Urban Areas ◽

Ecosystem Respiration ◽

Heterotrophic Respiration ◽

Sand Mixture ◽

Anthropogenic Stressors ◽

Unplanted Soil ◽

The Impact

Release of heavy metals, salts and other toxic agents in the environment is of increasing concern in urban areas. Contaminants not solely decline the quality of the local environment and affect the health of human population and urban ecosystems but are also spread through runoff and leaching into non-contaminated areas. Urban lawns are the most distributed green infrastructure in the cities. Management of lawn system may either exacerbate the negative effects of contaminants on lawn functioning either help to withstand the toxic effects and maintain the lawn ecosystem health and the efficient release of ecosystem services. &#160;The aim of this study was to evaluate the interactions between the lawn management, the lawn functioning, and the release into the soil of typical urban contaminants. For this purpose, Festuca arundinacea grass was planted in a turf-sand mixture with and without amendment addition (zeolite + vermicompost). To reproduce the impact of traffic-related contaminants in proximity of the road, pots were treated with a solution containing de-icing salt (NaCl) and 6 heavy metals (Zn, Cd, Pb, Cr, Cu, Ni), imitating road runoff solution. After contamination, half of pots was maintained at optimum soil water content (Smart irrigation), another half was left to periodical drying in order to simulate conditions with discontinuous watering (Periodical irrigation). The same experimental scheme was reproduced for unplanted soil. CO2 net ecosystem exchange (NEE), soil and ecosystem respiration as well as flux from unplanted soil (heterotrophic respiration) were measured shortly after the treatment (short-term) and up 3 months since the treatment start (long-term).Soil amendment stimulated plant productivity and increased the efficiency of the system in C uptake (+56% NEE). A relevant reduction of NEE was observed from 14 to 40 days after the application of traffic-related contaminants in both amended and non amended pots. During this period the contaminants had the greatest impact on lawn NEE subjected to Periodic irrigation (-49% and -66% in amended and non amended pots, respectively), while lawn under Smart irrigation was less affected (-35% and -26% in amended and non amended pots, respectively). Different respiration sources (ecosystem respiration, soil respiration, heterotrophic respiration) were characterized by different sensitivity to management and contamination. Heterotrophic flux was not sensitive to soil amending but declined with contamination with enhanced negative effect under Smart irrigation. Response of ecosystem respiration to contamination was less pronounced in confront to soil respiration suggesting leaf-level buffering.&#160; &#160;&#160;Three months later,&#160; the effect of contaminants on lawn gas exchange ceased for all treated pots. Instead, the irrigation effect persisted depending on whether pots were amended or not. In non amended pots NEE was reduced by 18% under Periodic irrigation, while this effect was not present in amended pots. We conclude, that performance of such green infrastructure as lawns in terms of C sequestration under multiple anthropogenic stressors could be efficiently improved through soil amending and irrigation control.Current research was financially supported by RFBR No. 19-29-05187 and RSF No. 19-77-30012.

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