The green highlighted spot on the map are the possible existent green area that have a big enough barrier to protect the edible plants from the toxic air from the pollution.
Where the coloured strips across the middle part of Bangkok city map symbolise the highly polluted area of the city, with the different colours representing different stage of harms
The relationship between the tree sizes and the amount of pollution in the air each tree can absorb
In January 2018, Bangkok experienced a smog that caused the government to issue a health warning to “at risk” residents such as children and the elderly.
Air Quality Index (AQI) formulas usually include up to six main pollutants including PM 2.5, PM 10, carbon monoxide, sulfur dioxide, nitrogen dioxide and ground level ozone. The World Health Organization has isolated PM 10 and PM 2.5 as the most detrimental to human health.
The Pollution Control Department reported PM 2.5 dust in the Bangkok Metropolitan during the beginning of the year was measured at 72-95 micro grams per m3, with the likelihood that it would increase. Compares with a World Health Organization (WHO)guideline of an annual average of no more than 10 micro-grams.
There are about 10 millions cars running in Bangkok city each days creating as much as 100 millions kg of smog that contains different kind of pollution each days
Difference in tree sizes give content a different amount of carbon. Bigger trees are usually older and can captured more carbon dioxide from the atmosphere, the maximum amount of carbon the large tree ( in the city area) can adsorb is around 20 kg per year.