Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Growing green roofs

07.09.2009
Sedum studied as practical, high-performing roof cover

One way to maximize the eco-friendly factor of a structure is to include a green roof—and this doesn't refer to the paint color. "Greening" a roof, or covering a roof with vegetation, is gaining popularity in North America, where the number of green roofs increased 30% from 2006 to 2007.

Benefits of green roofs include improved storm water management, energy conservation, reduced noise and air pollution, improved biodiversity, and even a better return on investment than traditional roofing.

But a healthy roof requires the selection of a species that can survive extreme climates and propagate easily to reduce erosion and weed growth. Kristin L. Getter of Michigan State University's Department of Horticulture led a study to determine the effect of the growing medium's depth on the success of green roofs. The research study, published in a recent issue of HortScience, focused on Sedum, a variety of succulent known for its drought tolerance.

Plots were constructed using the drainage mats and waterproofing systems typical of green roofs, but the growing material varied in depth from 4 cm, 7 cm, and 10 cm. Twelve species of Sedum were planted, fertilized, and watered once. The moisture of the growing material was measured at random times each week. Measurements of chlorophyll fluorescence were taken to monitor the health of the plants during a variety of environmental conditions.

Plants were monitored over the course of four years. Since the average lifespan of the inorganic components of a green roof is about 45 years, the researchers determined that it was important to study the longevity of the plants. The study found that the shallowest plot had the lowest moisture levels on average and dried the fastest after a rain. At the 4-cm depth, four species failed to exhibit significant growth over the 4-year period.

Five species showed no or little growth at the 7-cm depth, and six species showed no or little growth at a depth of 10 cm. Some species declined over the 4-year period at the varying depths. The remaining plants that flourished were the same species for all three depths (S. floriferum, S. sexangulare, S. spurium 'John Creech', and S. stefco). The 4-cm depth also included two other species (S. hispanicum and S. reflexum 'Blue Spruce').

Furthermore, the results indicate that, for the surviving and most-abundant species, there is no benefit to depths greater than 7 cm, which would appear to be good news considering shallow depths are more desirable because they make for lighter roof loads. "However, at deeper depths, these plants would likely be healthier, contain greater biomass, and be less susceptible to adverse environmental conditions. This study shows the importance of growing medium depth for plant performance and demonstrates the need for long-term evaluation of species for use in this green practice", concluded the researchers.

The complete study and abstract are available on the ASHS Hortscience electronic journal web site: http://hortsci.ashspublications.org/cgi/content/abstract/44/2/401

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application.

Michael W. Neff | EurekAlert!
Further information:
http://www.ashs.org

More articles from Ecology, The Environment and Conservation:

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Big data approach to predict protein structure

27.03.2017 | Life Sciences

Parallel computation provides deeper insight into brain function

27.03.2017 | Life Sciences

Weather extremes: Humans likely influence giant airstreams

27.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>