Which Trees Protect You Best from Pollution?
Created By RISC | 1 day ago
Last modified date : 1 day ago
Your air purifier might be working hard during the dust season but trees are also heroes in filtering out dust!
Trees can trap PM2.5 with hairy, smooth, or rough leaves or with their complex branches. They also absorb pollutants through their stomata while performing photosynthesis.
16 plant species were tested with incense smoke inside a box for 30 minutes. "Aglaonema" worked best, capturing PM2.5 at 30.87%, followed by the "Snake Plant" with 23.70%.
Assoc. Prof. Dr. Chairat Tri-Trapsuntorn tested plants in a closed system with a 1 cubic meter volume, starting with a PM2.5 concentration of 450-500 micrograms per cubic meter. "Velvet Carpet" reduced dust by over 60% and "Snake Plant" by over 40%. These ornamental plants can grow indoors or near windows to capture dust before it blows into your house.
If you have outdoor space, you can also design a garden to help reduce pollution.
Researchers from King Mongkut’s University of Technology Thonburi, Srinakharinwirot University, and Kasetsart University published a prototype garden using trees to sustainably reduce PM2.5 dust, supported by the National Research Council of Thailand (NRCT). This garden mimics an ecosystem where trees have diverse characteristics. They selected trees with 3 height levels:
- Large trees, such as Royal Poinciana, Indian Rosewood, and Champak
- Medium-sized trees, such as Moke and Ficus
- Shrubs, such as Areca Palm, Peace Lily, Bird’s Nest Fern, Aglaonema, Calathea, and Peacock Calathea
The 3-tiered planting system helps to block and trap dust. Plant at least 2 layers: a layer of small shrubs facing the wind and a second layer alternating between medium-sized shrubs and large trees. This arrangement slows airflow and allows the dust particles to be trapped more effectively by plant leaves. Moisture from transpiration increases the weight of the dust particles, making them fall faster. Watering the plants once a week helps clean the leaves and increase soil moisture. The system can block dust by 20-60%.
Story by Panpisu Julpanwattana, Senior Sustainable Designer and TREES-A Specialist, RISC
References:
Kantitat Thapsuwan, Siradech Surit. (2021). Dust Particle Capture from Incense Smoke Using Indoor Plants. Journal of Buddhist Social Science and Anthropology, 6(12), 80-93.
Assoc. Prof. Dr. Chairat Treesubsuntorn. (2022). Sustainable PM Phytoremediation by Perennial Plants. National Research Council of Thailand.