Sedum groundcover variably enhances performance and phenolic concentrations of perennial culinary herbs in an urban edible green roof

ABSTRACT Urban agriculture on green roofs has tremendous potential to enhance food security, economic opportunities, and community building in cities yet faces unique ecological challenges including limited soil moisture content for crops. We compared the effects of two green roof soil moisture management practices, sedum (Sedum album) groundcover versus watering, on performance and quality of three perennial culinary herbs: thyme, mint, and oregano. Individually and interactively, sedum groundcover and watering significantly impacted parameters of performance (biomass, vitality, and module coverage) and quality (total phenolic concentrations) of the three culinary herbs during early stages of establishment while having variable impacts during later developmental stages. Our results suggest that sedum groundcover can serve as a substitute for watering of hardy culinary herbs on green roofs on the basis of plant performance and quality. Findings can be applied to inform agroecological water management of herbs and other hardy specialty crops on green roofs toward enhancing their drought tolerance and advancing sustainable urban agriculture.

[1]  J. Stepp,et al.  Beyond yields: Climate change effects on specialty crop quality and agroecological management , 2016 .

[2]  O. Starry,et al.  Photosynthesis and water use by two Sedum species in green roof substrate , 2014 .

[3]  C. Matyas,et al.  Effects of Extreme Climate Events on Tea (Camellia sinensis) Functional Quality Validate Indigenous Farmer Knowledge and Sensory Preferences in Tropical China , 2014, PloS one.

[4]  J. Lundholm,et al.  Species interactions in green roof vegetation suggest complementary planting mixtures , 2014 .

[5]  Adam S. Phillips,et al.  Seasonal aspects of the recent pause in surface warming , 2014 .

[6]  A. Kaliora,et al.  Herbal infusions; their phenolic profile, antioxidant and anti-inflammatory effects in HT29 and PC3 cells. , 2013, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[7]  Rachel S. Meyer,et al.  Biodiversity and phytochemical quality in indigenous and state‐supported tea management systems of Yunnan, China , 2013 .

[8]  Claire L. Smith,et al.  Urban particulate pollution reduction by four species of green roof vegetation in a UK city , 2012 .

[9]  Joy Knoblauch.  Agriculture in urban planning; generating livelihoods and food security , 2012 .

[10]  A. Tsatsakis,et al.  Chemoprevention of liver cancer by plant polyphenols. , 2012, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[11]  C. Orians,et al.  Sedum cools soil and can improve neighboring plant performance during water deficit on a green roof , 2011 .

[12]  Leigh J. Whittinghill,et al.  The role of green roof technology in urban agriculture , 2011, Renewable Agriculture and Food Systems.

[13]  J. MacIvor,et al.  Insect species composition and diversity on intensive green roofs and adjacent level-ground habitats , 2011, Urban Ecosystems.

[14]  J. Bousselot,et al.  Moisture Content of Extensive Green Roof Substrate and Growth Response of 15 Temperate Plant Species during Dry Down , 2011 .

[15]  E. Kennelly,et al.  White and green teas (Camellia sinensis var. sinensis): variation in phenolic, methylxanthine, and antioxidant profiles. , 2010, Journal of food science.

[16]  A. Krumbein,et al.  Genotypic and climatic influence on the antioxidant activity of flavonoids in Kale (Brassica oleracea var. sabellica). , 2010, Journal of agricultural and food chemistry.

[17]  L. Bengtsson,et al.  Runoff water quality from intensive and extensive vegetated roofs , 2009 .

[18]  J. Lundholm,et al.  Water uptake in green roof microcosms: Effects of plant species and water availability , 2008 .

[19]  J. Porter,et al.  Crop responses to climatic variation , 2005, Philosophical Transactions of the Royal Society B: Biological Sciences.

[20]  S. C. Kaushik,et al.  Performance evaluation of green roof and shading for thermal protection of buildings , 2005 .

[21]  J. Pereira,et al.  How plants cope with water stress in the field. Photosynthesis and growth. , 2002, Annals of botany.

[22]  J. Koricheva,et al.  Seasonal changes in birch leaf chemistry: are there trade-offs between leaf growth and accumulation of phenolics? , 2002, Oecologia.

[23]  Francisco A. Tomás-Barberán,et al.  Phenolic compounds and related enzymes as determinants of quality in fruits and vegetables , 2001 .

[24]  Miguel A. Altieri,et al.  The greening of the “barrios”: Urban agriculture for food security in Cuba , 1999 .

[25]  V. Ossipov,et al.  Variation of total phenolic content and individual low-molecular-weight phenolics in foliage of mountain birch trees (Betula pubescens ssp.tortuosa) , 1996, Journal of Chemical Ecology.

[26]  J. A. Barone,et al.  HERBIVORY AND PLANT DEFENSES IN TROPICAL FORESTS , 1996 .

[27]  C. Nichols-orians.  Environmentally Induced Differences in Plant Traits: Consequences for Susceptibility to a Leaf‐Cutter Ant , 1991 .

[28]  J. Schultz,et al.  Chemical defense production in Lotus corniculatus L. II. Trade-offs among growth, reproduction and defense , 1990, Oecologia.

[29]  David F. Rhoades,et al.  Offensive-Defensive Interactions between Herbivores and Plants: Their Relevance in Herbivore Population Dynamics and Ecological Theory , 1985, The American Naturalist.

[30]  F. Stuart Chapin,et al.  Carbon/nutrient balance of boreal plants in relation to vertebrate herbivory , 1983 .

[31]  D. McKey.  Adaptive Patterns in Alkaloid Physiology , 1974, The American Naturalist.

[32]  Leigh J. Whittinghill,et al.  Up on the Roof: Considerations for Food Production on Rooftops , 2016 .

[33]  P. Jones,et al.  Global warming and changes in drought , 2014 .

[34]  M. Hermy,et al.  Mediterranean open habitat vegetation offers great potential for extensive green roof design , 2014 .

[35]  Timothy Carter,et al.  Ecological impacts of replacing traditional roofs with green roofs in two urban areas , 2008 .

[36]  R. Holloway.  Rare Invertebrates Colonizing Green Roofs in London , 2007 .

[37]  A. Drescher.  Food for the cities: urban agriculture in developing countries , 2004 .

[38]  T. Doré,et al.  Relationships between Biomass and Phenolic Production in Grain Sorghum Grown under Different Conditions , 2001 .

[39]  Peter Kareiva,et al.  Plant defense, herbivory, and climate change. , 1993 .