The effects of growth form on the impact of companion planting of nectar-producing plant species with Sedum album for extensive green roofs

To select plant species and species combinations for northern climates, mats with different plant species and species combinations were constructed on a green roof plant production farm and later transported and installed on an urban rooftop. There were three treatments: two different planting combinations, which together consisted of 10 diverse plant species [both stonecrop (Sedum) species and nonstonecrop species], and a control, which consisted of 26 stonecrop species used for standard mat production. Growth measurements and observations were made at both sites and special attention was paid to the performance of species during the harvest, transportation, and installation stages, as well as during recovery postinstallation. All species but false rock cress (Aubrieta cultorum) were found to be suitable for extensive green roof applications in northern climates, although there were variations of suitability among the species. Good, mediocre, and poor interactions formed between numerous species, displaying different levels of compatibility. Finally, all species were considered appropriate for a mat production system; species that failed to germinate, species planted postinstallation, the frequently displaced rolling hens and chicks (Jovibarba sobolifera), and false rock cress were exceptions. Overall, many species in this study displayed successful, well-rounded growth. Based on results, species and species combinations were recommended for extensive green roofs in northern climates.

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Nutrient Leaching in Extensive Green Roof Substrate Layers With Different Configurations

10.21203/rs.3.rs-601414/v1 ◽

2021 ◽

Author(s):

Chen Xu ◽

Zaohong Liu ◽

Guanjun Cai ◽

Jian Zhan

Keyword(s):

Green Roofs ◽

Pollution Source ◽

Nutrient Leaching ◽

Rainfall Runoff ◽

Rainfall Events ◽

Rainfall Characteristics ◽

Substrate Layer ◽

Rainwater Runoff ◽

The Impact ◽

Extensive Green Roofs

Abstract Due to substrate layers with different substrate configurations, extensive green roofs (EGRs) exhibit different rainfall runoff retention and pollution interception effects. In the rainfall runoff scouring process, nutrient leaching often occurs in the substrate layer, which becomes a pollution source for rainwater runoff. In this study, six EGR devices with different substrate layer configurations were fabricated. Then, the cumulative leaching quantity (CLQ) and total leaching rate (TLR) of NH4+, TN and TP in the outflow of nine different depth simulated rainfall events under local rainfall characteristics were evaluated and recorded. Furthermore, the impact of different substrate configurations on the pollution interception effects of EGRs for rainfall runoff was studied. Results show that a mixed adsorption substrate in the EGR substrate layer has a more significant rainfall runoff pollution interception capacity than a single adsorption substrate. PVL and PVGL, as EGRs with layered configuration substrate layers, exhibited good NH4+-N interception capacity. The CLQ and TLR of NH4+-N for PVL and PVGL were -114.613 mg and -63.43%, -121.364 mg and -67.16%, respectively. Further, the addition of biochar as a modifier significantly slowed down the substrate layer TP leaching effect and improved the interception effect of NH4+-N and TN. Moreover, although polyacrylamide addition in the substrate layer aggravated the nitrogen leaching phenomenon in the EGRs outflow, but the granular structure substrate layer constructed by it exhibited a significantly inhibited TP leaching effect.

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EFFECTS OF SUBSTRATES AND PLANT SPECIES ON WATER QUALITY OF EXTENSIVE GREEN ROOFS

Applied Ecology and Environmental Research ◽

10.15666/aeer/1402_077091 ◽

2016 ◽

Vol 14 (2) ◽

pp. 77-91 ◽

Cited By ~ 7

Author(s):

C-F. CHEN

Keyword(s):

Water Quality ◽

Plant Species ◽

Green Roofs ◽

Extensive Green Roofs

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Amount of water runoff from different vegetation types on extensive green roofs: Effects of plant species, diversity and plant structure

Landscape and Urban Planning ◽

10.1016/j.landurbplan.2011.11.001 ◽

2012 ◽

Vol 104 (3-4) ◽

pp. 356-363 ◽

Cited By ~ 116

Author(s):

Ayako Nagase ◽

Nigel Dunnett

Keyword(s):

Species Diversity ◽

Plant Species ◽

Green Roofs ◽

Plant Species Diversity ◽

Water Runoff ◽

Vegetation Types ◽

Plant Structure ◽

Extensive Green Roofs

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The impact of extensive green roofs on the improvement of thermal performance for urban areas in Mediterranean climate with reference to the city of Jijel in Algeria

10.1063/1.5039250 ◽

2018 ◽

Cited By ~ 1

Author(s):

M. C. Lehtihet ◽

A. Bouchair

Keyword(s):

Thermal Performance ◽

Urban Areas ◽

Mediterranean Climate ◽

Green Roofs ◽

The Impact ◽

The City ◽

Extensive Green Roofs

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Cooling Performances on Rainless Days of Extensive Green Roofs Planted with Different Ornamental Species

HortScience ◽

10.21273/hortsci11507-16 ◽

2017 ◽

Vol 52 (3) ◽

pp. 467-474

Author(s):

Yann-Jou Lin ◽

Ai-Tsen Su ◽

Bau-Show Lin

Keyword(s):

Plant Species ◽

Plant Cover ◽

Ornamental Plants ◽

Green Roofs ◽

Species Selection ◽

Aesthetic Quality ◽

Four Seasons ◽

Canopy Volume ◽

Extensive Green Roofs ◽

Selection Of

This study investigated the cooling performances of extensive green roofs (EGRs) planted with 12 ornamental plants on rainless days in a subtropical city for 1 year. Imitating the construction of an EGR, 48 modules were constructed and each module was planted as a monoculture with 100 plants each. Plant growth and greening performance were measured every 2 weeks. Temperatures, solar radiation intensities, and substrate water contents were measured continuously and recorded every 5 minutes. The analyzed results showed that both plant species selection and seasonal variation had a significant impact on the noontime cooling benefit. The modules planted with taller plants, more extensive plant cover, higher albedo, and greater canopy volume had a greater noontime cooling benefit. As the seasons changed, the albedo and canopy volume of the modules were primarily responsible for differences in the noontime cooling benefit provided by the different plant species. Over an entire year of observation, the results of this research could inform the selection of plant species by landscape designers for EGRs with the aim of providing greater cooling benefits and aesthetic quality overall four seasons.

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Moisture Content of Extensive Green Roof Substrate and Growth Response of 15 Temperate Plant Species during Dry Down

HortScience ◽

10.21273/hortsci.46.3.518 ◽

2011 ◽

Vol 46 (3) ◽

pp. 518-522 ◽

Cited By ~ 25

Author(s):

Jennifer M. Bousselot ◽

James E. Klett ◽

Ronda D. Koski

Keyword(s):

Moisture Content ◽

Plant Species ◽

Green Roof ◽

Green Roofs ◽

Herbaceous Plant ◽

Herbaceous Species ◽

Extensive Green Roof ◽

Dry Down ◽

Porous Soils ◽

Extensive Green Roofs

Success of extensive green roof vegetation depends primarily on associated plant species' ability to survive the low moisture content of the substrate. As a result of the well-drained nature of the substrate, plants adaptable to dry, porous soils are primarily used in extensive green roof applications. Although Sedum species have dominated the plant palette for extensive green roofs, there is growing interest in expanding the plant list for extensive green roof systems. To effectively select suitable plants, species need to be evaluated in terms of their response to gradual and prolonged dry down of the substrate. A study to determine the relative rates of dry down for 15 species was conducted in greenhouse trials. During dry downs that extended over 5 months, the substrate of succulent and herbaceous species dried down at different rates. The change in moisture content of the substrate was not consistent among succulent and herbaceous plant species during the initial 18 d of dry down. Despite differences in rate of dry down, the succulent species, as a group, maintained viable foliage for over five times longer than the herbaceous species. The revival rates of the succulent species were nearly double those of the herbaceous species. Therefore, not only are succulent species more likely to survive during periods of drought, but these species are more likely to resume growth soon after water is again made available.

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Investigating the Plant Species and Rainfall Factors on Stormwater Retention Performance of Extensive Green Roofs in Malaysia

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.9.15279 ◽

2018 ◽

Vol 7 (3.9) ◽

pp. 71

Author(s):

Chow Ming Fai ◽

Muhammad Fadhlullah Abu Bakar ◽

Lariyah Mohd Sidek1 Wong Jee Khai

Keyword(s):

Plant Species ◽

Green Roofs ◽

Water Runoff ◽

Storm Events ◽

Native Plant ◽

Retention Performance ◽

Rainfall Characteristics ◽

Native Plant Species ◽

Extensive Green Roofs ◽

Stormwater Retention

Information on the influences of native plant species and rainfall characteristics on the stormwater retention performance of extensive green roofs in Malaysia is still scarce. More local data is still required because rainfall and runoff generation processes in tropical environment are very different from the temperate regions. This study is aimed to investigate the stormwater retention performance of native plant species in extensive green roofs with respect to different rainfall characteristics in Malaysia. Two test beds consist of pro-mixing potting soil were vegetated each with different native plant species (Axonopus Compressus (cow grass), Portulaca Grandiflora (sedum) and one test bed with no vegetation (bare ground) was prepared as a control. A total of 22 significant storm events were collected over a 3-month period from March 2016 to May 2016. The rainfall depths for monitored storm events were ranged from 4.5 mm to 63.2 mm and rainfall intensities ranged from 0.5mm/hr to 58.5 mm/hr. The results showed that sedum exhibited higher mean runoff retention percentage than grass which is 75.8% and 70.9%, respectively. Bare soil was the least effective for reducing water runoff with retention percentage of 62.6%. Overall, sedum and grass species provided 90.6% and 88.2% of cumulative rainfall retention in this study. The rainfall depth and intensity are correlated negatively with stormwater retention performance of green roofs. Meanwhile, longer dry weather period are likely to increase the water retention capacity of green roof.

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