Wet season hydrological performance of green roofs using native species under Mediterranean climate

We report the rapid acidification of forest soils in the San Bernardino Mountains of southern California. After 30 years, soil to a depth of 25 cm has decreased from a pH (measured in 0.01 M CaCl2) of 4.8 to 3.1. At the 50-cm depth, it has changed from a pH of 4.8 to 4.2. We attribute this rapid change in soil reactivity to very high rates of anthropogenic atmospheric nitrogen (N) added to the soil surface (72 kg ha–1 year–1) from wet, dry, and fog deposition under a Mediterranean climate. Our research suggests that a soil textural discontinuity, related to a buried ancient landsurface, contributes to this rapid acidification by controlling the spatial and temporal movement of precipitation into the landsurface. As a result, the depth to which dissolved anthropogenic N as nitrate (NO3) is leached early in the winter wet season is limited to within the top ~130 cm of soil where it accumulates and increases soil acidity.

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Photovoltaic-green roofs: a life cycle assessment approach with emphasis on warm months of Mediterranean climate

Journal of Cleaner Production ◽

10.1016/j.jclepro.2014.03.006 ◽

2014 ◽

Vol 72 ◽

pp. 57-75 ◽

Cited By ~ 22

Author(s):

Chr. Lamnatou ◽

D. Chemisana

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Mediterranean Climate ◽

Green Roofs ◽

Assessment Approach

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Establishment and Persistence of Sedum spp. and Native Taxa for Green Roof Applications

HortScience ◽

10.21273/hortsci.40.2.391 ◽

2005 ◽

Vol 40 (2) ◽

pp. 391-396 ◽

Cited By ~ 155

Author(s):

Michael A. Monterusso ◽

D. Bradley Rowe ◽

Clayton L. Rugh

Keyword(s):

Native Species ◽

Green Roof ◽

Green Roofs ◽

Geographic Area ◽

Michigan State University ◽

State University ◽

Native Plant ◽

Visual Appearance ◽

Extensive Green Roofs ◽

The U.S

Although the economic, environmental, and aesthetic benefits of green roofs have been recognized for decades, research quantifying these benefits has been limited—particularly in the U.S. Green roof usage and research is most prevalent in Germany, but can also be seen in several other European countries and Canada. If green roof installations are to be successful in Michigan and the rest of the U.S., then a better understanding of what specific taxa will survive and thrive under harsh rooftop conditions in this geographic area is required. Nine simulated rooftop platforms containing three commercially available drainage systems were installed at Michigan State University. Eighteen Michigan native plants planted as plugs and nine Sedum spp. planted as either seed or plugs were evaluated over three years for growth, survival during both establishment and overwintering, and visual appearance. All Sedum spp. tested were found to be suitable for use on Midwestern green roofs. Of the eighteen native plant taxa tested, Allium cernuum L., Coreopsis lanceolata L., Opuntia humifosa Raf., and Tradescantia ohiensis L. are suitable for use on unirrigated extensive green roofs in Michigan. If irrigation is available, then other native species are potential selections.

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Decreasing Water Footprint of Electricity and Heat by Extensive Green Roofs: Case of Southern Italy

Sustainability ◽

10.3390/su122310178 ◽

2020 ◽

Vol 12 (23) ◽

pp. 10178 ◽

Cited By ~ 2

Author(s):

Behrouz Pirouz ◽

Stefania Anna Palermo ◽

Mario Maiolo ◽

Natale Arcuri ◽

Patrizia Piro

Keyword(s):

Energy Consumption ◽

Water Consumption ◽

Experimental Analysis ◽

Energy Production ◽

Mediterranean Climate ◽

Water Footprint ◽

Green Roof ◽

Green Roofs ◽

Air Conditioner ◽

Roof Temperature

Electrical and energy production have a noticeable water footprint, and buildings′ share of global energy consumption is about 40%. This study presents a comprehensive experimental analysis of different thermal impacts and water consumption of green roofs in a Mediterranean climate. The study aims to investigate the use of water directly for green roofs and reduce the water footprint of energy in summer and winter due to its thermal impacts. The measurements were carried out for an extensive green roof with an area of 55 m2 and a thickness of 22 cm, and direct water consumption by a green roof and direct and indirect water consumption by cooling and heating systems were analyzed. According to the analysis, in summer, the maximum roof temperature on a conventional roof was 72 °C, while under the green roof it was 30.3 °C. In winter, the minimum roof temperature on a conventional roof was −8.6 °C, while under the green roof it was 7.4 °C. These results show that green roofs affect energy consumption in summer and winter, and the corresponding thermal requirements for the building have a water footprint regarding energy production. In summer, the thermal reduction in the water footprint by a green roof was 48 m3 if an evaporative air conditioner is used and 8.9 m3 for a compression air conditioner, whereas the water consumed in the green roof was 8.2 m3. Therefore, using water directly in the green roof would reduce the energy consumption in buildings, and thus less water has to be used in power plants to provide the same thermal impact. In winter, green roofs′ water consumption was higher than the thermal water footprint; however, there is no need to irrigate the green roof as the water consumed comes from precipitation. This experimental analysis determines that in the Mediterranean climate, green roofs allow the achievement of the same thermal conditions for buildings in both summer and winter, with a reduction in water consumption.

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Green roof and ground-level invertebrate communities are similar and are driven by building height and landscape context

Journal of Urban Ecology ◽

10.1093/jue/juz024 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Jacinda R Dromgold ◽

Caragh G Threlfall ◽

Briony A Norton ◽

Nicholas S G Williams

Keyword(s):

Native Species ◽

Green Space ◽

Ground Level ◽

Green Roofs ◽

Vegetation Types ◽

Invertebrate Community ◽

Invertebrate Communities ◽

Surrounding Environment ◽

Native Grassland ◽

Family Level

Abstract Green roofs are increasingly promoted for urban biodiversity conservation, but the value of these novel habitats is uncertain. We aimed to test two hypotheses: (i) green roofs can support comparable invertebrate family and order richness, composition and abundances to ground-level habitats and (ii) green roofs planted with native species from local habitats will support a richer invertebrate community at family and order level than other green roofs. We sampled the invertebrate community on green roofs dominated by native grassland or introduced succulent species in Melbourne, Australia, and compared these to the invertebrate community in ground-level sites close by, and sites with similar vegetation types. The only significant differences between the invertebrate communities sampled on green roofs and ground-level habitats were total abundance and fly family richness, which were higher in ground-level habitats. Second hypothesis was not supported as invertebrate communities on green roofs supporting a local vegetation community and those planted with introduced Sedum and other succulents were not detectably different at family level. The per cent cover of green space surrounding each site was consistently important in predicting the richness and abundance of the invertebrate families we focussed on, while roof height, site age and size were influential for some taxa. Our results suggest that invertebrate communities of green roofs in Melbourne are driven largely by their surrounding environment and consequently the effectiveness of green roofs as invertebrate habitat is highly dependent on location and their horizontal and vertical connection to other habitats.

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