This research examines how distinct climatic conditions affect the runoff reduction functions of green roofs by comparing performance in Vancouver, BC, Kelowna, BC and Shanghai, P.R. China. To quantify the reduction in runoff volume effectuated by green roofs, both the Soil Conservation Service Curve Number (SCS-CN), crop coefficient method and the Hargreaves-Samani method are applied in calculating the annual water gains and losses of green roofs during a year of average precipitation, using local climate data such as precipitation, evapotranspiration, and temperature. Using a soil water balance model, the research also analyzes the change in soil water content of a typical green roof with a soil depth of 150 mm, and compares the potential irrigation requirements of plants with low versus high water requirements in each of the three cities. The calculation results show that the typical green roof could reduce annual rooftop runoff by 29% in Vancouver, 55% in Shanghai, and 100% in Kelowna. Furthermore, these results illustrate the important role that soil properties, soil depth, and plant selection play in maintaining growth of plants and minimizing green roof irrigation requirements. Les résultats montrent qu'un toit vert typique pourrait réduire la quantité les eaux de ruissellement annuels de 29% à Vancouver, de 55% à Shanghai et de 100% à Kelowna. De plus, il s'avère que les spécificités du toit vert, en particulier, la qualité du sol, l'épaisseur du substrat de croissance et la séléction des plantes jouent un role important pour assurer la bonne croissance des plantes et amoindrir le besoin d'irrigation du toit vert.

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This article focuses on the role landscape architects and planners can take in the creation of urban food production landscapes. It draws upon a series of local projects and visions to demonstrate how this can be accomplished. Within the context of Metro Vancouver, there are signifi cant constraints to expansion due to geographical limitations, a steadily growing population, and large low-density residential areas. Successful food production strategies for the future can be achieved by integrating urban agriculture into a wider city planning context, and transcending the creation of community gardens. The challenge is to provide custom solutions for specifi c neighborhoods, at all scales, from the urban core to the suburbs, and beyond. The design of food production sites within the urban core and, particularly, the edge condition between residential development, and farmland, will challenge landscape architects to create real places of interaction between man and land.

This research reports the potential environmental benefits derived from an overall intervention of living skins [green roofs and green façades] in the city core of Vancouver, Canada. These include the reduction in cooling and heating demand; reduction in stormwater runoff; improvement of air quality; enrichment of urban biodiversity and urban agriculture; reduction in the urban heat island effect; the contribution to carbon neutral architecture; and an assessment of different construction systems. It analyses the environmental behaviour of the selected site by applying the Seattle Green Factor.The research focuses on the energy performance of a typical residential building within the selected area, through the Energy 10 simulation program. It also analyses the reduction in stormwater runoff through the Curve Number Method; as well as the reduction of CO 2 emissions based on related research.Obtained data shows that the total energy used for cooling is reduced [100%] through the greening of roofs and façades, which means the 9% of the total energy demand by the studied building. It also shows that CO 2 emissions would decrease by 9%; and stormwater runoff would be reduced by 4%. The research compares these findings with previous related research on green roofs, façades and urban forests. Its findings suggest that these types of "living skins" interventions achieve better environmental performance in warm-dry climates where cooling energy demand is greater.

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