Department of Landscape Architecture, College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; Department of Landscape Architecture and Regional & Community Planning, College of Architecture, Planning and Design, Kansas State University, Manhattan, KS 66506, USA.
Department of Landscape Architecture and Regional & Community Planning, College of Architecture, Planning and Design, Kansas State University, Manhattan, KS 66506, USA.
Sci Total Environ. 2019 Dec 20;697:134089. doi: 10.1016/j.scitotenv.2019.134089. Epub 2019 Aug 24.
Many prairie plant habitats have similarities to the harsh and stressful growing environments of green roofs. In the Mid-Continent Region of the USA under a hot summer climate, little research has been done to study prairie plant communities and their performance with different substrates on green roofs. To explore more sustainable, diverse green roof ecosystems, this research assessed the first-year growth (June to October 2018) on an experimental green roof in the Flint Hills Ecoregion, which has some of the most extensive coverage of intact tallgrass prairie in North America. A mixture of plants (four native prairie grasses and two sedums) were grown on two substrates-a commercial substrate (rooflite® extensive 800) and a regionally mixed substrate (Kansas BuildEx)-placed at two depths: 6.0-13.0 cm (called the "shallow depth") and 16.5-25.5 cm (called the "deep depth"). Plant height, coverage, survival, visual appearance, leaf stomatal resistance, and volumetric substrate water content were measured. Supplemental irrigation was provided equally to each experimental plot during the growing season. It was shown that the regionally mixed substrate had greater effect on plant height at the shallow depth and on coverage at the deep depth. However, volumetric water content was usually higher in the commercial substrate. Substrate type did not affect visual appearance and leaf stomatal resistance. Substrate moisture was inversely related to leaf stomatal resistance at low soil moisture levels. All prairie species survived, while Sedum reflexum had poor survival and coverage. Bouteloua curtipendula, Bouteloua gracilis, Schizachyrium scoparium, and Sedum rupestre performed well in a green roof community. Bouteloua dactyloides grew very well, but may be too aggressive when planted with sedums. The findings of this study will be of practical value for the design of mixed-species green roof systems in similar mid-continental regions with hot summers.
许多草原植物生境与绿色屋顶恶劣且有压力的生长环境相似。在美国中陆地区，炎热的夏季气候下，对于在绿色屋顶上使用不同基质的草原植物群落及其性能的研究很少。为了探索更可持续、更多样化的绿色屋顶生态系统，本研究评估了在北美拥有最广泛完整高草草原之一的弗林特山生态区的一个实验性绿色屋顶上的第一年生长情况（2018 年 6 月至 10 月）。在两种基质上种植了植物混合物（四种本地草原草和两种景天属植物）——一种商业基质（rooflite® extensive 800）和一种地区混合基质（Kansas BuildEx）——深度分别为 6.0-13.0 厘米（称为“浅层深度”）和 16.5-25.5 厘米（称为“深层深度”）。测量了植物高度、覆盖率、存活率、外观、叶片气孔阻力和基质体积含水量。在生长季节，每个实验小区均等提供补充灌溉。结果表明，地区混合基质对浅层深度的植物高度和深层深度的覆盖率有更大的影响。然而，商业基质中的体积含水量通常较高。基质类型对外观和叶片气孔阻力没有影响。在低土壤水分水平下，基质水分与叶片气孔阻力呈负相关。所有草原物种均存活，而 Sedum reflexum 存活率和覆盖率都较差。Bouteloua curtipendula、Bouteloua gracilis、Schizachyrium scoparium 和 Sedum rupestre 在绿色屋顶群落中表现良好。Bouteloua dactyloides 生长得非常好，但与景天属植物一起种植时可能过于侵略性。本研究的结果对于在夏季炎热的类似中陆地区设计混合物种绿色屋顶系统具有实际价值。
