Stormwater control measures (SCMs) in the form of highly permeable tree pits can be useful in two ways. On one hand, they can help reduce surface runoff and on the other hand, the presence of trees in these pits can potentially help mitigate the urban heat island effect. Therefore, it is important to understand the pit designs that underpin tree health and growth performances. Here in this study, four pit designs namely, a control which did not receive runoff water, another that receive runoff into a sandy clay loam soil, yet another that was filled with structural soil, and a third that received runoff into structural soil with an underdrain system, used to test and identify which designs were best able to maintain hydrological balance and growth of Calophyllum inophyllum in an urban area dominated by sandy clay loam soil. Trees in pits which had structural soil and drainage installed had 6-fold more growth than the controls (that received no stormwater runoff), and 3-fold more growth when compared against street trees grown in pits that had sandy clay loam soil (that had run off channelled towards these pits). Treatments with structural soils also experienced more efficient exfiltration rates which helped avoid waterlogging which in turn, benefitted growth. The lower exfiltration rates of the poorly drained sandy clay loam soils resulted in periods of saturation and subsequent slower tree growth. Treatments with structural soil together with drainage and those that had sandy clay loam soils were found to have saturated water levels at a depth greater than 400 mm and between 100−200 mm (from the surface), respectively. The outcomes from this study indicated that tree growth can be improved by channelling stormwater into tree pits with structural soil and especially those that also have drainage installed. Noteworthy however, is that while waterlogging may be avoided through the application of structural soil and a drainage system, the high exfiltration rates may result in water stress when rainfall is scarce though this did not happen here. The need for hydrological balance will be the key to successful urban street tree planting.

以高渗透性树坑形式存在的雨水控制措施 (SCM) 可以通过两种方式发挥作用。一方面，它们可以帮助减少地表径流，另一方面，这些坑中树木的存在可能有助于减轻城市热岛效应。因此，了解支撑树木健康和生长性能的坑设计非常重要。在本研究中，有四种坑设计，即一个不接收径流水的控制，另一个接收径流进入砂质粘壤土，另一个填充结构土壤，第三个接收径流进入结构土壤暗渠系统，用于测试和确定哪种设计最能保持水文平衡和金缕梅的生长在以砂质粘壤土为主的城市地区。安装了结构性土壤和排水系统的坑中树木的生长速度是对照（没有雨水径流）的 6 倍，与生长在沙质粘土（没有雨水径流）的坑中的行道树相比，其生长速度增加了 3 倍。流向这些坑）。结构性土壤的处理也经历了更有效的渗出率，这有助于避免积水，从而有利于生长。排水不良的砂质粘壤土的较低渗出率导致了饱和期和随后的较慢的树木生长。结构土加排水处理和砂质粘壤土处理被发现在深度大于 400 毫米和 100-200 毫米之间（离地表）具有饱和水位，分别。这项研究的结果表明，通过将雨水引导到带有结构性土壤的树坑中，尤其是那些还安装了排水系统的树坑，可以改善树木的生长。然而，值得注意的是，虽然可以通过应用结构土和排水系统来避免内涝，但当降雨稀少时，高渗漏率可能会导致缺水，尽管这在当地并没有发生。水文平衡的需要将是成功种植城市行道树的关键。当降雨稀少时，高渗漏率可能会导致缺水，尽管这种情况在这里没有发生。水文平衡的需要将是成功种植城市行道树的关键。当降雨稀少时，高渗漏率可能会导致缺水，尽管这种情况在这里没有发生。水文平衡的需要将是成功种植城市行道树的关键。