Effects Of Green Infrastructure Research Articles

Effect of green infrastructure on restoration of pollination networks and plant performance in semi‐natural dry grasslands across Europe

Abstract Agricultural intensification, afforestation and land abandonment are major drivers of biodiversity loss in semi‐natural grasslands across Europe. Reversing these losses requires the reinstatement of plant–animal interactions such as pollination. Here we assessed the differences in species composition and patterns of plant‐pollinator interactions in ancient and restored grasslands and how these patterns are influenced by landscape connectivity, across three European regions (Belgium, Germany and Sweden). We evaluated the differences in pollinator community assemblage, abundance and interaction network structure between 24 ancient and restored grasslands. We then assessed the effect of surrounding landscape functional connectivity (i.e. green infrastructure, GI) on these variables and tested possible consequences on the reproduction of two model plants, Lotus corniculatus and Salvia pratensis. Neither pollinator richness nor species composition differed between ancient and restored grasslands. A high turnover of interactions across grasslands was detected but was mainly due to replacement of pollinator and plant species. The impact of grassland restoration was consistent across various pollinator functional groups, whereas the surrounding GI had differential effects. Notably, bees, butterflies, beetles, and dipterans (excluding hoverflies) exhibited the most significant responses to GI variations. Interestingly, networks in restored grasslands were more specialised (i.e. less functionally redundant) than in ancient ones and also showed a higher number of insect visits to habitat‐generalist plant species. Landscape connectivity had a similar effect, with habitat‐specialist plant species receiving fewer visits at higher GI values. Fruit set in S. pratensis and L. corniculatus was unaffected by grassland type or GI. However, the fruit set in the specialist S. pratensis increased with the number of pollinator visits, indicating a positive correlation between pollinator activity and reproductive success in this particular species. Synthesis and applications. Our findings provide evidence of the necessity to enhance ecosystem functions while avoiding biotic homogenisation. Restoration programs should aim at increasing landscape connectivity which influences plant communities, pollinator assemblages and their interaction patterns. To avoid generalist species taking over from specialists in restored grasslands, we suggest reinforcing the presence of specialist species in the latter, for instance by means of introductions, as well as increasing the connectivity to source populations.

Heat risk assessment and response to green infrastructure based on local climate zones

The escalation of thermal risks is attributed to accelerating pace of urbanization. However, assessment and response to green infrastructure with respect to heat risk under different climate and function have been inadequate. This study intends to address these gaps by focusing on local climate zones (LCZs). Firstly, spatial characteristics of heat risk indexes (HRIs) constructed based on heat hazard-exposure-vulnerability for three large cities in 2010, 2015 and 2020 were explored. Secondly, whether HRI cross LCZs have significant differences was examined. Third, proportion and heat contribution of different HRI classes under different LCZs were quantified. Finally, effects of green infrastructure under different LCZs on HRI were analyzed. The results revealed consistent upward trends in the prevalence of sub-high and high HRIs from 2010 to 2015. HRIs exhibited significant spatial aggregation characteristics. Importantly, more than 95.83% of HRIs cross LCZs exhibited significant variations. The HRI for open building type was lower when compared to the compact LCZ types. Additionally, Normalized Difference Vegetation Index (NDVI) had a more pronounced mitigating effect on HRIs in compact high-rise (LCZ 1), compact mid-rise (LCZ 2), open high-rise (LCZ 4) and open mid-rise (LCZ 5). Updating the compact LCZ types to open LCZ types, avoiding configuration of LCZ 1 and 2, and prioritizing the configuration of NDVI enhancement in the existing LCZ 1, 2, 4 and 5, and increasing the amount of greenery by upgrading mono-structures to composite structures consisting of trees, shrubs and grasses and by implementing greening of façade are suggested to alleviate heat risk.

Effects of green infrastructure on the dispersion of PM2.5 and human exposure on urban roads

Urban green infrastructure (GI) has been widely demonstrated to effectively improve air quality in the built environment. However, due to the lack of comparative studies of the effects of different GI forms on PM2.5 dispersion, optimal GI designs suitable for different urban road types currently remain unclear. In this study, we adopted different roadside GI types in Hangzhou city as case studies and used the ENVI-met model to compare the effects of the different GI forms on PM2.5 dispersion and human exposure to PM2.5. The results indicated that 1) In open roads, the concave-shaped GI type could effectively reduce PM2.5 aggregation and human exposure on motorways, and the all-tree GI type performed the best in terms of sidewalk PM2.5 purification. 2) In street canyons, green roof and green screen were highly conducive to PM2.5 concentration reduction under commuter exposure compared with traditional green solutions. 3) There were trade-offs in the GI-PM2.5 interaction. GI types which can reduce pedestrian exposure tend to increase exposure in motorways. The same GI type deployed along the two different road types could yield completely opposite dispersion effects. Novel GI types had better environmental performance and relatively high economic cost. All decision-making should be based on the trade-offs between the advantages and disadvantages of GI. Our study also highlights the importance of comprehensive consideration of GI and road types and local wind conditions in future urban road planning and GI applications.

A new approach for roughness representation within urban dispersion models

The effects of green infrastructure on pollutant concentrations are greatly variable, essentially depending on the surrounding built-up environment and on local meteorological conditions. To simulate the effects of the presence of trees at urban scale, a reliable methodology is the Computational Fluid Dynamics (CFD) approach, however it needs high calculation costs. An alternative integral dispersion model is given by provided that a suitable parameterization for vegetation is included. In this work, we have developed and demonstrated a novel methodology, based on aerodynamic parameters, to include the aerodynamic effect of trees in an operational dispersion model, the ADMS-Urban. The aerodynamic parameters were derived using the morphometric method starting from open data containing information on buildings and trees. The new roughness parameter calculation method has produced the urban spatially varying roughness (USVR) and it was evaluated in different scenarios at the urban and neighborhood scale. The numerical outputs of the simulations were compared with observations from reference air quality stations collected within an ad-hoc intensive field campaign conducted in 2017 in the city of Bologna, Italy. The results of the comparison highlight that the introduction of the aerodynamic effects of buildings lead to great improvements in the performance of the model at both spatial scales and for the different study sites considered in this study. Conversely, the inclusion of trees in the calculation produces significant improvements only when conducting studies at high spatial resolution and for densely vegetated areas.

Meteorological Effects of Green Infrastructure on a Developing Medium Latin American City: A Numerical Modeling Assessment

Meteorological Effects of Green Infrastructure on a Developing Medium Latin American City: A Numerical Modeling Assessment

Assessment of Climate, Sizing, and Location Controls on Green Infrastructure Efficacy: A Timescale Framework

AbstractWe investigate how the effectiveness of green infrastructure (GI) to mitigate the frequency and magnitude of significant discharge events and combined sewer overflows (CSOs) depend on both climate and sewershed characteristics and propose a theoretical framework for a holistic assessment of GI's efficacy. The framework is based on the comparison of three characteristic timescales that control the production of peak discharge: rainfall duration (tr), travel time in the sewer network (tn), and the duration of rain that would be required to fill the GI's storage (tGI). Storm events can then be characterized by two ratios of these timescales: Tn = tn/tGI and Tr = tr/tGI. A third dimensionless number characterizes critical storms during which adverse events (such as CSOs) occur and allows us to identify the combinations of Tn and Tr for which GI may substantially mitigate those events. The results of numerical experiments with the model demonstrate that the storms for which GI can substantially reduce peak discharge and CSO volume typically occur in a narrow band of Tn and Tr. Within that band, the efficacy of GI may depend on the location of GI within the sewershed if network routing substantially affects the timing and magnitude of flood peaks. The proposed framework is applied to examine the efficacy of GI using historical precipitation data from two major U.S. cities: Philadelphia, PA, and Seattle, WA, and the results of this comparative analysis suggest that GI location is an important control on catchment‐scale GI efficacy in Philadelphia, but less so in Seattle.

Creating urban green infrastructure where it is needed – A spatial ecosystem service-based decision analysis of green roofs in Barcelona

As cities face increasing pressure from densification trends, green roofs represent a valuable source of ecosystem services for residents of compact metropolises where available green space is scarce. However, to date little research has been conducted regarding the holistic benefits of green roofs at a citywide scale, with local policymakers lacking practical guidance to inform expansion of green roofs coverage. The study addresses this issue by developing a spatial multi-criteria screening tool applied in Barcelona, Spain to determine: 1) where green roofs should be prioritized in Barcelona based on expert elicited demand for a wide range of ecosystem services and 2) what type of design of potential green roofs would optimize the ecosystem service provision. As inputs to the model, fifteen spatial indicators were selected as proxies for ecosystem service deficits and demands (thermal regulation, runoff control, habitat and pollination, food production, recreation, and social cohesion) along with five decision alternatives for green roof design (extensive, semi-intensive, intensive, naturalized, and allotment). These indicators and alternatives were analyzed probabilistically and spatially, then weighted according to feedback from local experts. Results of the assessment indicate that there is high demand across Barcelona for the ecosystem services that green roofs potentially might provide, particularly in dense residential neighborhoods and the industrial south. Experts identified habitat, pollination and thermal regulation as the most needed ES with runoff control and food production as the least demanded. Naturalized roofs generated the highest potential ecosystem service provision levels for 87.5% of rooftop area, apart from smaller areas of central Barcelona where intensive rooftops were identified as the preferable green roof design. Overall, the spatial model developed in this study offers a flexible screening based on spatial multi-criteria decision analysis that can be easily adjusted to guide municipal policy in other cities considering the effectiveness of green infrastructure as source of ecosystem services.

Climate-resilient urban planning and architecture with GREENPASS illustrated by the case study ‘FLAIR in the City’ in Vienna

Urban growth and climate change are 2 of the main challenges worldwide [20]. Cities are growing rapidly while average temperatures are rising, and extreme weather conditions, as heavy rain events, are becoming more frequently. Soon 4 out of 5 EU citizens are living in cities [6]. The results are increasing costs for health expenses and infrastructure damages. Urban planning processes have to consider future climate conditions and the impact on people, buildings and the urban environment. Until today there was no simple solution to measure and calculate the climate impacts of urban developments. GREENPASS® is a technological breakthrough, the world’s first software-based technology for climate-resilient and resource-efficient urban development. After 9 years of scientific research and development the technology can easily be used by urban planners as architects and be integrated into existing urban planning workflows and processes.With GREENPASS® the impact of buildings, materials and plants on urban climate become measurable and comparable in a standardized way – powered by ENVI-met®. It supports optimization of investments towards effects of Green Infrastructure (trees, green roofs and walls, …) such as cooling, thermal comfort, water retention and carbon sequestration. GREENPASS® allows to identify the optimal solution for any urban development. Supported projects receive finally a GREENPASS® certificate on their overall performance. The technology has already been applied successfully for more than 25 projects within Austria and Europe [3] and will be explained more in detail using the case study of ‘FLAIR in the City’ - the world’s first GREENPASS® Gold-certified residential building, located in Vienna/Austria.

Green infrastructure practices simulation of the impacts of land use on surface runoff: Case study in Ecorse River watershed, Michigan

As an urban fringe district, the Ecorse River watershed is faced with increased impervious area caused by urban expansion. Effects of Green Infrastructure (GI) practice implementation were simulated with the Long-Term Hydrologic Impact Assessment-Low Impact Development 2.1 model (L-THIA-LID 2.1). Suitable locations of each GI practice were identified, based on construction condition requirements and demand on GI practices in the study area. Using the data of 2011, various GI practice combination scenarios were explored according to the cost-efficiency of each GI practice. GI practice implementation scenarios in 2050 were also simulated based on projected land use and rainfall data. Results show that grassed swales, rain barrels (residential areas) and dry ponds were the top three most cost-efficient GI practices, with the cost at $1.5/m³/yr, $3.0/m³/yr and $3.4/m³/yr, respectively. Green roofs with rain cisterns (industrial and commercial area) were the most expensive GI practices, with the cost at $92.9/m³/yr. With the increase of investment in GI practices, the changing curves of the annual runoff volume, Total Nitrogen (TN) load and Total Phosphorus (TP) load reduction ratios match the law of diminishing marginal utility. The scenario with grassed swales, rain barrels, dry ponds and porous pavement would be the most cost-efficient scenario for runoff water quantity reduction. In addition, the scenario with additional wet ponds would be the most cost-efficient one for TN load and TP load reduction. GI practices in each scenario for expected 2050 conditions show better effectiveness on water quantity and quality management.

A panel data analysis of a spatial measurement of green infrastructure and its potential effectiveness on peak streamflow

Research on the possible benefits of green infrastructure as a hazard mitigation strategy has been limited by the lack of effective tools for the identification and measurement of the specific dimensions of green infrastructure particularly within highly developed urban environments. Consequently, there has been little empirical research conducted on the potential benefits of green infrastructure for reducing streamflow, an indicator of runoff and potential flooding mitigation. This study seeks to further research green infrastructure as a potential tool for hazard mitigation by examining its consequences for streamflow over a 2-year period in 2004 and 2010 for two key urban areas subject to flooding in Texas, USA (Austin and Houston Metropolitan areas) in panel models to assess the effectiveness of green infrastructure for reducing runoff as assessed by using streamflow gage data predicting annual peak flow. The statistical models suggested that green infrastructure contributes to reduce annual peak flow in urbanized watersheds. The effect in the fixed effects model suggests that with every percent increase in green infrastructure within the 100-year floodplain, peak annual flow decreased by 7.7% (R2 = 0.6985). The effects of green infrastructure outside the floodplain appeared to be significant, and its magnitude in the fixed effects model was − 7.1% (R2 = 0.6447). These differences suggest slightly greater consequences for preserving green infrastructure within floodplains when it comes to peak annual flows. Moreover, the analyses explained that green infrastructure in Austin appears to be more effective on peak annual flow when, compared to Houston, suggesting that green infrastructure has elevated consequences in areas with greater topographical diversity. The effectiveness of green infrastructure in critical places will help make a guideline for the balanced urban development with implementation of green infrastructure.

The effects of green infrastructure on exceedance of critical shear stress in Blunn Creek watershed

Green infrastructure (GI) has attracted city planners and watershed management professional as a new approach to control urban stormwater runoff. Several regulatory enforcements of GI implementation created an urgent need for quantitative information on GI practice effectiveness, namely for sediment and stream erosion. This study aims at investigating the capability and performance of GI in reducing stream bank erosion in the Blackland Prairie ecosystem. To achieve the goal of this study, we developed a methodology to represent two types of GI (bioretention and permeable pavement) into the Soil Water Assessment Tool, we also evaluated the shear stress and excess shear stress for stream flows in conjunction with different levels of adoption of GI, and estimated potential stream bank erosion for different median soil particle sizes using real and design storms. The results provided various configurations of GI schemes in reducing the negative impact of urban stormwater runoff on stream banks. Results showed that combining permeable pavement and bioretention resulted in the greatest reduction in runoff volumes, peak flows, and excess shear stress under both real and design storms. Bioretention as a stand-alone resulted in the second greatest reduction, while the installation of detention pond only had the least reduction percentages. Lastly, results showed that the soil particle with median diameter equals to 64 mm (small cobbles) had the least excess shear stress across all design storms, while 0.5 mm (medium sand) soil particle size had the largest magnitude of excess shear stress. The current study provides several insights into a watershed scale for GI planning and watershed management to effectively reduce the negative impact of urban stormwater runoff and control streambank erosion.

The cooling effect of green infrastructure on surrounding built environments in a sub-tropical climate: a case study in Taipei metropolis

Green infrastructure that provides cooling service is regarded as a critical urban planning strategy to mitigate urban heat. This study assesses important greenspace and matrix factors that contribute to greenspace cooling effect beyond greenspaces in Taipei metropolis using Landsat 8 satellite imagery. The results indicated that both greenspace and matrix features have jointly affected greenspace cooling intensity, but their cooling contributions to the mean temperature of greenspace and that of surrounding built environments were not necessarily identical or explicit. Larger greenspaces with compact/simple shape, containing more water elements and higher greenness tended to be cooler, whereas higher development intensity, lower tree proportion and fewer water elements in the matrix tended to produce warmer built environments. The influence of these features on temperature outside greenspaces varied by distance. With the distance increasing from greenspaces, the effect of greenspace features dropped and that of matrix features rose.

社区尺度绿色基础设施暴雨径流消减模拟研究

社区尺度绿色基础设施暴雨径流消减模拟研究

RETRACTED ARTICLE: The effectiveness of green infrastructure as a climate adaptation strategy for intensively-used landscapes: an example of the great crested newt

RETRACTED ARTICLE: The effectiveness of green infrastructure as a climate adaptation strategy for intensively-used landscapes: an example of the great crested newt