The development of City limits to provide space for more homes is a contentious subject addressed by advocates of both development and local environmental preservation groups during city council meetings. I have attended some sessions to understand issues from both sides better.
With the world population expected to increase 50% by 2100, development in every part of the world is necessary, and our area is no different. Advocates from both the development and environmental sides reside in homes that sit on previously cleared lands, but the issue is how proponents and advocates can work together.
We all live in the same environment. What do we put into it during development, and how does that react with naturally occurring compounds we also help to introduce while trying to mitigate the environmental impact?
The ozone layer in the upper atmosphere protects from ultraviolet light, but ozone gas at ground level is formed when Volatile Organic Compounds (VOCs) react with nitrous oxide - the byproduct of an engine - in the presence of sunlight. The ozone gas at ground level can lead to respiratory issues.
Plants and trees emit biogenetic VOCs in different quantities and types, depending on species and size. The VOCs are cast as a by-product of the photosynthetic process that absorbs carbon from the atmosphere while delivering oxygen. There are two primary compounds: isoprene and monoterpenes. Broadleaved trees, such as oaks, primarily emit the former, and pines and conifers emit the latter. Isoprene is far more reactive with nitrous oxide than monoterpenes to produce harmful ozone gas at ground level.
My question is this: Why is there an obsession to plant open field trees that require 1000 sq ft of root space in the front yard of every home in city developments, so that city planting points are met?
The highest vehicular traffic areas should have smaller specimens that emit smaller quantities of VOCs that are less reactive with car exhaust byproducts. Mitigation areas that provide new green space away from high-traffic routes for larger specimens should be identified, so nature can balance the environment without producing a negative impact.
Strategies like this may help balance development needs with environmental responsibility requirements. The survivability of larger tree specimens depends on their access to the correct soil and neighboring tree symbiosis, along with minimum human interaction.