A plant sociological approach for extensive green roofs in Mediterranean areas
Chiara Catalano, Università degli Studi di Palermo, Dipartimento SAF, phd student – Tecnologie per la sostenibilità e il risanamento ambientale
Riccardo Guarino, Università degli Studi di Palermo, Dipartimento STEBICEF, Sezione botanica
Stephan Brenneisen, Zürcher Hochschule für Angewandte Wissenschaften, Institut für Umwelt und Natürliche Ressourcen
Abstract
Extensive Green roofs can be an important mean for environmental mitigation if designed according to the principles of restoration ecology. Moreover, if optimally executed, properly managed and of sufficient extension, they could be assimilated to meta-populations of natural habitats, worth to be included in the biodiversity monitoring networks. The best example supporting this hypothesis is the Lake water plant Moos in Wollishofen (Zurich, Switzerland) where, on three 100 years old units of extensive green roofs, occur most of the typical flora of Mesobromion, including high density of some endangered orchid species. With this work, we propose a methodology approach for green roofs in Mediterranean areas, based on a practical plant sociology understanding of EU Directive 92/43: a recognition of Natura 2000 habitat that could be imitated on roofs in terms of characteristic species and substrates. Our results lead to three category groups: those linked to sandy substrates (psammophilous vegetation), to gravely-pebbly substrates (glareicolous vegetation) and to xeromorfic soils (garrigues and dry grasslands). According to the last theories and practical application for grasslands restoration, we suggest a method applied and studied in Switzerland for green roofs, based on diaspore hay transfer from a donor meadow, in order to obtain the highest plant species richness and diversity.
Keywords : Extensive green roofs, plant sociology, habitat replication, biodiversity assessment, Natura 2000, hay transfer.
Applied polymers as a suitable replacement for the natural materials in the various layers of green roofs and their characteristics
Naser Valipour Motlagh, University of Birjand
Zahra Arabpoor, University of Sistan and Baluchestan
Mahdiye Soltanpourgazar, Ferdowsi University of Mashhad Faculty of Engineering
Abstract
Green roof is an environment-friendly structure developed globally as a result of increasing urbanization.
In this review paper we first tried to collect classification, structure and materials of green roofs.
Increasing water availability of substrate using water retention additives is also collected and studied in this paper. Accordingly, different materials are applied in green roofs, among which polymers have attracted a lot of attention. Polymer materials are widely used in different layers of green roofs due to their characteristics like light weight, which is an important concern about green roofs. So, in the next step, we gathered different polymeric materials that are used in different layers of green roof or can be used in this structure. For example, low density polyethylene (LDPE) or polyethylene (PP) material use as physical barriers. Therefore, this article provides an opportunity to review and compare different polymeric materials that have been studied in different articles in various layers.
Keywords: Green roof, Polymers, Recycled polymers, Water retention additives
Benefits of A Modular Green Roof Technology
Elena Korola, Natalia Shushunovaa
Institute of Environmental Engineering and Construction Mechanization, National Research Moscow State University of Civil Engineering, 26 Yaroslavskoe Shosse, Moscow, 129337, Russian Federation
Abstract
This article aims to the various benefits of a modular green roof technology. Nowadays smart solutions of green roofs are popular for their ecological, technical, economic benefits and esthetic qualities. Green roofs are used in residential, commercial, government and public buildings. Innovative energy-efficient construction technologies will bring great benefit to the ecology and help to relief the heat island effect. The purpose of this research is to provide an effective apparatus and method for green roof system, the principal results of this research are focused on adjusting of optimal physical parameters of green roof modules. This friendlyenvironmental green roof technology is oriented on policy of sustainable development and protection of the urban ecology.
Keywords: Sustainable development; modular green roof system; urban ecology; energy-efficient construction technologies; green building.
Designing green roofs for arid and semi-arid climates.
The route towards the adaptive approach
P.A. Nektariosa and N. Ntoulas
Laboratory of Floriculture and Landscape Architecture, Department of Crop Science, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
Abstract
It is widely accepted that green roofs provide multiple benefits to the urban environment and the well-being of the cities’ residents. Despite their acknowledged contribution to the contemporary cityscape and environment, their broad implication in arid and semi-arid regions is extremely limited compared to northern countries.
Thus, it is of great interest and importance to identify the hurdles that delay the broad implication of green roofs in challenging climatic zones. These hurdles can be categorized either as governmental or technical or psychological even though they all intermingle and interact. More specifically, in the arid and semi-arid climatic zones, such as those of the Mediterranean basin, the governmental incentives are absent forcing the private sector and the homeowners to take the initiative. In those cases, investing in green roofing can only be justified if green roofs are usable and aesthetically pleasing since the preference of the public has been documented towards the intensive green roof types. However, taking into account that the majority of existing buildings are old and can bare minimal additional loading, it is obvious that green roof substrate depth must be minimal. All the above parameters are contradicting and have led us to the introduction of a new green roof category, namely the adaptive type. Adaptive green roofs have minimal substrate depth ranging from 5 to 15 cm but utilize a broad palette of plant species such as groundcovers, turfgrasses, medicinal and aromatic plants coppices and small shrubs. All the above are feasible due to minimal and prudent irrigation inputs. The current presentation provides a thorough review of the plant species evaluated in adaptive green roof systems concerning their response to different substrate types and depths, their tolerance to either deficit irrigation or drought and their irrigation requirements.
Keywords: adaptive green roof systems, Mediterranean zone, substrate depth, substrate type, native plant species, deficient irrigation, drought tolerance
More to come!