Turfgrass tested in shallow green roof substrates

Oct 21, 2013

Green roofs, rooftops covered with vegetation, provide multiple environmental and aesthetic benefits. These "living roofs" are increasing in popularity worldwide. As more cities invest in green roofs, planners are challenged to find plants that can thrive in shallow planting conditions and with minimal maintenance. A new study from researchers in Greece offers recommendations for the use of turfgrass in green roof environments.

Nikolaos Ntoulas, Panayiotis A. Nektarios, and Efthimia Nydrioti from the Department of Crop Science at Agricultural University of Athens published the results of their experiments with Manilagrass in HortScience. Author Nikolaos Ntoulas explained that although turfgrasses meet the three requirements of plants recommended for use in urban environments (aesthetics, function, and recreation), these grasses have seldom been evaluated on extensive green roofs due to their high water demands. Ntoulas and colleagues compared the growth of Zoysia matrella 'Zeon' in two different substrates. They also investigated the impact of increasing either substrate depth or the amount of irrigation on Manilagrass growth and recovery potential during and after moisture deficit periods. The 2-year outdoor study was conducted on a rooftop at the Laboratory of Floriculture and Landscape Architecture in Athens.

The experiments involved three factors: two substrate types, two substrate depths, and two irrigation regimes replicated five times. "The results showed that, during moisture deficit periods, green turf cover (GTC), normalized difference vegetation index (NDVI), and leaf relative water content (RWC) were most affected by substrate depth, moderately affected by irrigation regime, and, to a lesser extent, by substrate type," the authors said. "Turfgrass growth and physiological status were best during moisture deficit conditions in the deeper profile (15 cm) using the higher amount of irrigation (6 mm) and the locally mixed substrate."

The scientists concluded that substrate depth was the most significant factor that improved growth and drought resistance of Manilagrass; the deeper substrate resulted in improved drought tolerance when compared with the shallow substrate. "However, because load is a crucial issue on construction, if substrate depth must be reduced to 7.5 cm, then should exceed 6 mm every 3 days to have adequate growth and successfully overcome summer moisture deficit periods," they recommended.

Explore further: Sailing against prevailing winds, spotting big islands: Calculating how the Pacific was settled

More information: hortsci.ashspublications.org/content/48/7/929.abstract

Related Stories

How does your green roof garden grow?

Dec 29, 2010

Growing plants on rooftops is an old concept that has evolved from simple sod roofing to roof gardens and new, lightweight "extensive green roofs". Modern green roofs have environmental and social benefits; they can reduce ...

How green are green roofs?

Sep 21, 2011

Covered with a growing medium and plants, green roofs can benefit a building's insulation, control storm-water drainage and remove pollution from the air, as well as provide wildlife habitats.

There's no one-size-fits-all green roof, studies show

Apr 25, 2012

Green roofs – rooftops covered with a layer of vegetation–are getting a lot of credit for providing environmental benefits. They have been found to reduce storm water runoff from buildings, conserve ...

Recommended for you

York's anti-malarial plant given Chinese approval

Apr 24, 2015

A new hybrid plant used in anti-malarial drug production, developed by scientists at the University of York's Centre for Novel Agricultural Products (CNAP), is now registered as a new variety in China.

The appeal of being anti-GMO

Apr 24, 2015

A team of Belgian philosophers and plant biotechnologists have turned to cognitive science to explain why opposition to genetically modified organisms (GMOs) has become so widespread, despite positive contributions ...

Micro fingers for arranging single cells

Apr 24, 2015

Functional analysis of a cell, which is the fundamental unit of life, is important for gaining new insights into medical and pharmaceutical fields. For efficiently studying cell functions, it is essential ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.