Search Results (46)

Rapid urbanization in Karachi, Pakistan, has resulted in increased impervious surfaces, leading to significant challenges, such as frequent flooding, urban heat islands, and loss of vegetation. These issues pose challenges to urban resilience, livability, and sustainability, which further demand solutions that incorporate urban greening and effective water management. This research uses remote sensing technologies and Geographic Information Systems (GISs), to analyze current surface treatments and their relationship to Karachi’s blue-green infrastructure. By following this approach, we evaluate flood risk and identify key flood-conditioning factors, including elevation, slope, rainfall distribution, drainage density, and land use/land cover changes. By utilizing the Analytical Hierarchy Process (AHP), we develop a flood risk assessment framework and a comprehensive flood risk map. Additionally, this research proposes an innovative Sponge City (SC) framework that integrates nature-based solutions (NBS) into urban planning, especially advocating for the establishment of green infrastructure, such as green roofs, rain gardens, and vegetated parks, to enhance water retention and drainage capacity. The findings highlight the urgent need for targeted policies and stakeholder engagement strategies to implement sustainable urban greening practices that address flooding and enhance the livability of Karachi. This work not only advances the theoretical understanding of Sponge Cities but also provides practical insights for policymakers, urban planners, and local communities facing similar sustainability challenges. Full article

Nature-based solutions (NBSs) offer a promising framework for addressing urban environmental challenges while also enhancing social and economic resilience. As cities seek to achieve carbon neutrality, the integration of NBSs with renewable energy sources (RESs) presents both an opportunity and a challenge, requiring an interdisciplinary approach and an innovative planning strategy. This study aims to explore potential ways of achieving synergies between NBSs and RESs to contribute to urban resilience and climate neutrality. Focusing on the railway station district in western Thessaloniki (Greece), this research is situated within the ReGenWest project, part of the EU Cities Mission. This study develops a comprehensive, well-structured framework for integrating NBSs and RESs, drawing on principles of urban planning and energy systems to address the area’s specific spatial and ecological characteristics. Using the diverse typologies of open spaces in the district as a foundation, this research analyzes the potential for combining NBSs with RESs, such as green roofs with photovoltaic panels, solar-powered lighting, and solar parking shaders, while assessing the resulting impacts on ecosystem services. The findings reveal consistent benefits for cultural and regulatory services across all interventions, with provisioning and supporting services varying according to the specific solution applied. In addition, this study identifies larger-scale opportunities for integration, including the incorporation of NBSs and RESs into green and blue corridors and metropolitan mobility infrastructures and the development of virtual power plants to enable smart, decentralized energy management. A critical component of the proposed strategy is the implementation of an environmental monitoring system that combines hardware installation, real-time data collection and visualization, and citizen participation. Aligning NBS–RES integration with Positive Energy Districts is another aspect that is stressed in this paper, as achieving carbon neutrality demands broader systemic transformations. This approach supports iterative, adaptive planning processes that enhance the efficiency and responsiveness of NBS–RES integration in urban regeneration efforts. Full article

Rapid urbanisation and climate change have intensified extreme rainfall events, exacerbating stormwater runoff and overwhelming urban drainage systems. Nature-based solutions, such as green roofs with integrated retention capacity, offer promising strategies to mitigate these challenges. This study investigates the influence of substrate thickness and retention volume on the stormwater retention and evapotranspiration (ET) performance of three green roof variants under extreme rainfall scenarios (natural and 5-, 30- and 100-year events). Using lysimeter-based experimental setups, we show that the overall retention capacity is highly dependent on the filling status of the retention layer. Near full capacity, retention performance decreases significantly, resulting in runoff behaviour similar to that of conventional green roofs, while empty systems store up to 99% of rainfall. In addition, ET rates tend to decrease in systems with higher substrate layers and larger retention spaces due to reduced surface evaporation and greater thermal insulation. However, higher substrate layers store more water, allowing plants to maintain transpiration during dry periods, potentially increasing total cumulative ET over time. Overall, this study highlights the importance of designing intensive retention green roofs with dynamic water management to optimise both rainwater retention and ET, thereby increasing urban resilience to increasing rainfall extremes caused by climate change. Full article

This study examines the thermal impacts of green and blue infrastructure in Hilalkent Neighborhood, Elazığ City, in Turkey, using ENVI-met 5.6.1 software. Six design scenarios were proposed and their impact on air temperature, relative humidity, mean radiant temperature (Tmrt), physiological equivalent temperature (PET), and wind speed during August and January was analyzed. The simulation results were verified via field measurements using the Lutron AM-4247SD Weather Forecast Station at a height of 2.0 m above the ground. Data were collected in August 2023 and January 2024. The findings of this study indicate that existing vegetation in the study area provides a cooling effect of 0.8 °C during August. The addition of 10% grass coverage further reduced air temperature by 0.3 °C, while a 20% increase in tree density led to a 0.6 °C temperature reduction. The inclusion of a 10% water surface resulted in a 0.4 °C decrease in air temperature, and the implementation of extensive roof gardens contributed to an additional 0.2 °C reduction during the August period. The combined implementation of blue–green infrastructure in the study area achieved a total cooling effect of 1.5 °C during August. During January, the proposed scenarios led to a reduction in average temperatures by 0.1 °C to 0.4 °C compared to the base scenario, which may not be favorable for thermal comfort in colder conditions. Relative humidity values decreased during the August and Tmrt values were directly proportional to air temperature changes in both August and January. The results of this study provide valuable insights for urban planners and policymakers, demonstrating the effectiveness of blue–green infrastructure in mitigating the urban heat island (UHI) effect. These findings highlight the importance of integrating climate-responsive design strategies into urban planning to enhance thermal comfort and environmental sustainability in cities. Full article

The relocation of Indonesia’s capital to Nusantara in East Kalimantan has raised concerns about microclimatic impacts resulting from proposed land use and land cover (LULC) changes. This study explored strategies to mitigate these impacts by using dynamical downscaling with the Weather Research and Forecasting model integrated with the urban canopy model (WRF-UCM). Numerical experiments at a 1 km spatial resolution were used to evaluate the impacts of green and mitigation strategies on the proposed master plan. In this process, five scenarios were analyzed, incorporating varying proportions of blue–green spaces and modifications to building walls and roof albedos. Among them, scenario 5, with 65% blue–green spaces, exhibited the highest cooling potential, reducing average urban surface temperatures by approximately 2 °C. In contrast, scenario 4, which allocated equal shares of built-up areas and mixed forests (50% each), achieved a more modest reduction of approximately 1 °C. The adoption of nature-based solutions and sustainable urban planning in Nusantara underscores the feasibility of climate-resilient urban development. This framework could inspire other cities worldwide, showcasing how urban growth can align with environmental sustainability. Full article

Nature-based solutions play an essential role in enhancing urban soil hydrology by improving water retention properties, reducing surface runoff, and improving water infiltration. This bibliometric analysis study reviewed the literature and identified the current trends in research related to nature-based solutions in urban soil hydrology. The study has the potential to highlight current research areas and future hot topics in this specific field. The research used the Scopus database to collect published articles from 1973 to 2023. The keywords (“trees” OR “vegetation” OR “green infrastructure” OR “blue green infrastructure” OR “greenery” OR “nature-based solutions” AND “hydrolog*” AND “urban” OR “city” OR “soil”) were searched in the Scopus database, and 13,276 articles were retrieved. The obtained publications were analyzed for bibliometric analysis by using Bibliometrix (v4.3.0) and VOSviewer (v1.6.20) software. The maximum number of publications (970) related to nature-based solutions and urban soil hydrology was published in 2023. Additionally, countries such as the United States and China published 54.2% of articles of the global research in the field of nature-based solutions and urban soil hydrology, with 36% from the USA and 18.2% of articles from China. The bibliometric analysis depicted that Beijing Normal University led this specific research field with 540 articles. The top country in terms of collaboration was the USA, with 26.17% as compared to the global countries. The most productive researcher identified was Jackson, T.J., as he had the highest number of publications, showing his considerable contribution to the field. Furthermore, the most frequent keywords used in this research area were hydrology, ecosystem services, urban hydrology, remote sensing, nature-based solutions, climate change, runoff, stormwater management, water quality, vegetation, green roof, bioretention, and land use. The early research trending topics in this field from 2015 to 2023 were remote sensing, soil moisture, climate change, drought, green infrastructure, machine learning, and nature-based solutions. The bibliometric analysis identified limited interdisciplinary research integrations, not using well-significant and standardized methodologies for the evaluation of urban soil hydrology, and under-representation of research from developing countries as current research gaps. Future research directions highlight advanced methods such as combining data-driven technologies with traditional hydrological approaches, and increasing international collaboration, specifically in developing nations, to address urban soil hydrological problems properly. Full article

Urban green infrastructure (UGI) plays a vital role in mitigating climate change risks, including urban development-induced warming. The effective maintenance and monitoring of UGI are essential for detecting early signs of water stress and preventing potential fire hazards. Recent research shows that plants close their stomata under limited soil moisture availability, leading to an increase in leaf temperature. Multi-spectral cameras can detect thermal differentiation during periods of water stress and well-watered conditions. This paper examines the thermography of five characteristic green wall and green roof plant types (Pachysandra terminalis, Lonicera nit. Hohenheimer, Rubus tricolor, Liriope muscari Big Blue, and Hedera algeriensis Bellecour) under different levels of water stress compared to a well-watered reference group measured by thermal cameras. The experiment consists of a (1) pre-test experiment identifying the suitable number of days to create three different levels of water stress, and (2) the main experiment tested the suitability of thermal imaging with a drone to detect water stress in plants across three different dehydration stages. The thermal images were captured analyzed from three different types of green infrastructure. The method was suitable to detect temperature differences between plant types, between levels of water stress, and between GI types. The results show that leaf temperatures were approximately 1–3 °C warmer for water-stressed plants on the green walls, and around 3–6 °C warmer on the green roof compared to reference plants with differences among plant types. These insights are particularly relevant for UGI maintenance strategies and regulations, offering valuable information for sustainable urban planning. Full article

Green roofs (GRs) have been widely adopted as an effective Green Infrastructure (GI) practice in cities worldwide, offering ecosystem services such as stormwater management and reduction of the urban heat island effect. However, their widespread implementation is still limited by a lack of local research and uncertain research findings. As a result, the potential benefits of GRs often cannot justify their high investment costs. Previous studies have sought to enhance the effectiveness of GRs by evaluating new GR systems, such as integrating GRs with green walls, blue roofs, photovoltaic (PV) panels, radiant cooling systems, as well as the use of innovative materials in GR substrates. Biochar, a carbon-rich substrate additive, has been recently investigated. The addition of biochar improves water/nutrient retention of GRs, thereby increasing substrate fertility and promoting plant performance. Although studies have examined the effects of biochar on GR plant growth, long-term observational studies focusing on the impacts of various biochar-related parameters remain necessary. Therefore, this research aims to assess the performance of GR plants with different biochar parameters, namely, amendment rates, application methods, and particle sizes. A one-year-long observational data of plant height, coverage area, and dry weight from six GR test beds was collected and analyzed. Results demonstrate the positive impacts of biochar on plant growth in different biochar-GR setups and types of plant species (wallaby grass, common everlasting, and billy buttons). The GR with medium biochar particles at the amendment rate of 15% v/v had the best plant performance. This contributes to increasing the feasibility of GRs by maximizing GR benefits to buildings where they are installed while reducing GR costs of irrigation and maintenance. The conclusions were further supported by observed data indicating reduced substrate temperature, which in turn reduces building energy consumption. Since vegetation is crucial in determining the effectiveness of a GR system, this study will offer valuable insights to GR designers and urban planners for developing optimal biochar-amended GR systems. Such systems provide numerous benefits over traditional GRs, including enhanced plant growth, reduced building energy costs, a shorter payback period, and reduced structural requirements. Full article

Yuzhen Palace in Wudang Mountain, established in the 10th year of the Yongle reign of the Ming dynasty (1412 AD), is a significant heritage site within the ancient architectural complex of Wudang Mountain, recognized as a UNESCO World Heritage Site. Despite being entirely relocated, the original paintings on the wooden beams of the Dragon and Tiger Hall exhibit clear characteristics of early Ming dynasty style, potentially being the only surviving wooden painted structures from the Ming dynasty in Wudang Mountain. To protect these valuable cultural relics and provide accurate information regarding the construction period of the paintings, this study sampled the paintings from the central and western sections of the front eaves in the Dragon and Tiger Hall. Using optical microscopy, scanning electron microscopy (SEM), Raman spectroscopy, and infrared spectroscopy, the study analyzed the stylistic features, material composition, and craftsmanship of the paintings. The results indicate that the paintings are typical official Xuanzi paintings from the early Ming dynasty, consistent with the style of the Golden Roof in Taihe Palace, Wudang Mountain. The pigments used are all natural minerals: azurite (2CuCO₃·Cu(OH)₂) for blue, malachite (CuCO₃·Cu(OH)₂) for green, and vermilion (HgS) and hematite (Fe₂O₃) for red, reflecting typical early Ming dynasty characteristics. The craftsmanship shows that the paintings were applied directly onto the wooden components without a ground layer, using ink lines to outline the images, and a thin ground layer made of tung oil mixed with lime was applied under the oil coating. This study provides scientific material analysis and data support for the subsequent protection and restoration of the Yuzhen Palace architectural complex, ensuring the preservation of these historically and artistically significant relics for future generations. Full article

Global environmental and health issues such as climate change and the COVID-19 pandemic have highlighted the weaknesses of current urban systems, including the poor availability and accessibility of green and public spaces in cities. Nature-based Solutions are configured as promising solutions to increase the resilience and health of the built environment by addressing climate and pandemic issues, promoting the psycho-physical well-being of users and proposing solutions for the protection of the environment and ecosystems. Following a systematic review of the scientific literature using the PRISMA methodology, this study aims to provide a taxonomic framework for Nature-based Solutions for the built environment that is applicable to the urban and building scales, highlighting key benefits in addressing pandemic and climate challenges and achieving urban resilience. This framework proposes a holistic and multifunctional approach that will prove to be a useful tool for researchers and policy makers to incorporate greening strategies into urban regeneration and redevelopment processes. The application of Nature-based Solutions still seems to be limited. It is therefore necessary to raise awareness of this issue among citizens and policy makers and to promote close co-operation between the different actors in territorial decision-making processes. Full article

Increased land use as a result of urbanization is one of the most rapid human-driven causes of biodiversity loss. Urbanization negatively affects human health because of poor nutrition, non-communicable diseases (NCDs) and health problems related to air pollution. Nature-based solutions (NbSs) for sustainable food production in combination with reduced land and water use are essential for the reduction in biodiversity loss, human health and nutrition. This systematic review aims to assess the effects of NbSs that positively contribute to biodiversity on human health and wellbeing in urban settings worldwide. Secondarily, other factors, such as safety, attractiveness, inequity and accessibility, that may have a potential role in the use of NbSs will be evaluated. For the purpose of the FENS conference, only results related to nutrition and food security will be presented. The PRISMA guidelines will be followed. Full-length articles in English language conducted in 2000 and published in 2010 will be included. Both quantitative and qualitative studies are eligible. Due to the diversity of studies, the quality assessment with diverse studies (QuADS) tool will be used for the quality assessment of the studies included. The statistical analysis will depend on the heterogeneity and the feasibility of harmonization of the data. PubMed, Web of Science and Scopus were searched. The initial search yielded 14386 publications. After the removal of duplicates, 8730 titles and abstracts were screened. Currently, 881 full texts out of 2928 have been screened, from which 69 (8%) studies reported outcomes related to human nutrition and food security. Most of the studies took place in urban gardens (61%). Urban farming (25%) and farmers’ markets followed (25%). Vegetation/greenness in cities was considered as an NbS by 6% of the studies. Less studied NbSs were green roofs, general green spaces, urban foraging and urban blue spaces (3% each). Gardening has been shown to be beneficial for the wellbeing and nutrition of various populations. Due to the high land use for the feeding of urban populations, alternative food production techniques without soil use are important. Soil-free rooftop farms and vertical farming could increase the vegetable and fruit production in cities and improve the diet quality of citizens. Full article

This study investigates the potential for green roofs to support pollinator diversity and abundance in urban ecosystems through the altered floral phenology and floral abundance of plants. Floral phenology and the floral abundance of green roof plants are compared to plants grown at grade on the Front Range in Fort Collins, Colorado, and how these changes may affect pollinator biodiversity in urban ecosystems. An independent block design is employed, within one green roof and one ground-level garden, approximately 120 m apart, with replicate plants of 4 species in each garden. Pollinator observations were made weekly during the bloom period for each species. Blue vane traps were used to passively measure pollinator diversity along a transect between the green roof sites and the sites at grade. The total number of flowers per plant is variable between site types, depending on the plant species. However, all species of plants tested bloomed earlier when grown on the green roof than when grown at grade. Pollinator abundance and diversity were low at both site locations. Green roofs may provide foraging opportunities earlier in the season in temperate regions, which can extend the duration of floral foraging opportunities when supported by green infrastructure at grade. Full article

An analytical hierarchy model of the impact of solar reflectance, thermal emittance, heat transfer coefficient, and heat storage coefficient on building energy consumption was established through the implementation of orthogonal design experiments. The EnergyPlus software (v9.0.1) was utilized to simulate building energy consumption across diverse climatic regions in China, providing essential benchmarks for the orthogonal design. The results of the range analysis consistently indicate that, barring regions characterized by extremely cold climates, solar reflectance emerges as the predominant factor exerting an influence on building energy consumption. As geographical latitude increases, the impact of the heat transfer coefficient becomes progressively larger, while the weight of thermal reflectance concurrently diminishes. Drawing upon the principles rooted in the gradient refractive rate theory and the concept of atmospheric window radiation, a range of high-reflectance and high-emittance cool roof coatings in various colors were meticulously developed. A spectrophotometer was employed to precisely quantify their reflectance properties, and simulations were subsequently conducted to scrutinize their energy-saving characteristics. The results demonstrate that the cool roof coatings that were developed using the methodology described in this paper exhibit substantial enhancements in reflectance, with increases of 0.24, 0.25, 0.37, and 0.35 for the yellow, red, blue, and green cool roofing materials, respectively, in comparison to conventional colored coatings. Under typical summer conditions, these enhancements translate to significant reductions in roof temperatures, ranging from 9.4 °C to 14.0 °C. Moreover, the simulations exploring the cooling loads for the roofs of differing colors consistently revealed remarkable energy savings. These savings were quantified to be 4.1%, 3.9%, 5.5%, and 5.4%, respectively, when compared to conventional coatings of the corresponding colors. These findings offer valuable insights into strategies for optimizing the energy efficiency of buildings through the application of high-reflectance cool roofing materials. Full article

Considering the rising concern over climate change and the need for local food security, productive blue-green roofs (PBGR) can be an effective solution to mitigate many relevant environmental issues. However, their cost of operation is high because they are intensive, and an economical operation and maintenance approach will render them as more viable alternative. Low-cost sensors with the Internet of Things can provide reliable solutions to the real-time management and distributed monitoring of such roofs through monitoring the plant as well soil conditions. This research assesses the extent to which a low-cost image sensor can be deployed to perform continuous, automated monitoring of a urban rooftop farm as a PBGR and evaluates the thermal performance of the roof for additional crops. An RGB-depth image sensor was used in this study to monitor crop growth. Images collected from weekly scans were processed by segmentation to estimate the plant heights of three crops species. The devised technique performed well for leafy and tall stem plants like okra, and the correlation between the estimated and observed growth characteristics was acceptable. For smaller plants, bright light and shadow considerably influenced the image quality, decreasing the precision. Six other crop species were monitored using a wireless sensor network to investigate how different crop varieties respond in terms of thermal performance. Celery, snow peas, and potato were measured with maximum daily cooling records, while beet and zucchini showed sound cooling effects in terms of mean daily cooling. Full article

Soil liquefaction often occurs as a secondary hazard during earthquakes and can lead to significant structural and infrastructure damage. Liquefaction is most often documented through field reconnaissance and recorded as point locations. Complete liquefaction inventories across the impacted area are rare but valuable for developing empirical liquefaction prediction models. Remote sensing analysis can be used to rapidly produce the full spatial extent of liquefaction ejecta after an event to inform and supplement field investigations. Visually labeling liquefaction ejecta from remotely sensed imagery is time-consuming and prone to human error and inconsistency. This study uses a partially labeled liquefaction inventory created from visual annotations by experts and proposes a pixel-based approach to detecting unlabeled liquefaction using advanced machine learning and image processing techniques, and to generating an augmented inventory of liquefaction ejecta with high spatial completeness. The proposed methodology is applied to aerial imagery taken from the 2011 Christchurch earthquake and considers the available partial liquefaction labels as high-certainty liquefaction features. This study consists of two specific comparative analyses. (1) To tackle the limited availability of labeled data and their spatial incompleteness, a semi-supervised self-training classification via Linear Discriminant Analysis is presented, and the performance of the semi-supervised learning approach is compared with supervised learning classification. (2) A post-event aerial image with RGB (red-green-blue) channels is used to extract color transformation bands, statistical indices, texture components, and dimensionality reduction outputs, and performances of the classification model with different combinations of selected features from these four groups are compared. Building footprints are also used as the only non-imagery geospatial information to improve classification accuracy by masking out building roofs from the classification process. To prepare the multi-class labeled data, regions of interest (ROIs) were drawn to collect samples of seven land cover and land use classes. The labeled samples of liquefaction were also clustered into two groups (dark and light) using the Fuzzy C-Means clustering algorithm to split the liquefaction pixels into two classes. A comparison of the generated maps with fully and manually labeled liquefaction data showed that the proposed semi-supervised method performs best when selected high-ranked features of the two groups of statistical indices (gradient weight and sum of the band squares) and dimensionality reduction outputs (first and second principal components) are used. It also outperforms supervised learning and can better augment the liquefaction labels across the image in terms of spatial completeness. Full article