Siti Nur Hannah Ismail
Thesis Title: Rainfall interception and retention by different vegetation covers under simulated rainfall
2007 – 2011, BA Landscape Architecture (Hons), International Islamic University Malaysia
2012 – 2013, MA Landscape Management, University of Sheffield
Before I pursued my masters’ degree, I spent four years as an undergraduate designing parks and open spaces. I also had the opportunity to work as a landscape architect at a landscape firm in Malaysia, where my creativity was challenged to design landscape concepts for parks and gardens. However, I believe that beauty will not be complete without management and maintenance practices, and that form should always follow after function. I felt the need to obtain more understanding of landscape management and that it is equally important as designing a landscape.
After completing my MA in Landscape Management at the Department of Landscape, University of Sheffield, I gained very useful insights and knowledge on landscape management. This has increased my awareness on how landscape can help sustain the environment in addition to providing social, economical and most importantly environmental benefits. My masters’ thesis emphasized the roles of different types of green infrastructures as sustainable water management strategies, which I felt was a critical issue to address in response to climate change impact.
Coming from a country with tropical climate, I have experienced variations in rainfall and the consequences of flash flooding problems especially during the monsoon seasons in Malaysia. However, intensification and increased frequency of heavy rainfall events do not only affect Malaysia, but many regions including the UK, due to climate change effects. These extreme weather conditions, combined with rapid urbanization and building densification are increasing severity of flood risks. Therefore, the urge for me to challenge myself to undertake this research topic for my PhD was encouraged by my supervisor Dr Ross Cameron. Hence, I started my PhD in October of 2014.
My research focuses on the roles of low-growing urban vegetation to determine water-holding capacity of shrubs and herbaceous plants, and also to determine if certain leaf traits affect raindrop capture and retention. Experiments were undertaken using a small range of genotypes with contrasting leaf types and traits to determine their ability to retain water on their leaves. Retention rates were assessed under different precipitation scenarios (large and small droplet sizes). Current results on both, individual and community plants suggest that fine-leaved species retain a proportionally greater volume of rainwater than coarse-leaved species. Based on the findings of this research, principles identified pertaining to leaf characteristics may help landscape designers to select appropriate plant species according to their benefits that could potentially contribute to reducing runoff in urban areas. The role of low-growing plants should not be neglected; as plant’s functional traits play an important role in influencing water retention, this may help to adopt more effective planting design for urban landscape in the future.
As moisture retention by vegetation is also highly influenced by moisture storage capacity, climatic conditions and evapo-transpiration (ET) losses. Current work is being carried out to observe moisture release from vegetation and soil moisture recharge capacity, as well as the influence of leaf characteristics in the efficiency of ET rates.
- Green infrastructure,
- urban landscape,
- climate change adaptation through sustainable approaches,
- reducing stormwater runoff and flood risks using vegetation.