In the daily surf ‘n’ seek for innovative ways of greening the (barren) urban landscape I happened upon a small company, Groene Gevel Design (Green Gable Design), in Rotterdam. The question, “what could possibly be new in the urban greening world” may have crossed your mind at this point. Moss is the answer and Groene Gevel Design is in the process of using moss for gables/facades, rooftops, sound barriers along highways and more.
What are mosses and what makes them different from other plants? Mosses are bryophytes which are non-vascular plants. They are similar to liverworts by their multi-cellular rhizoids. Rhizoids act in a similar fashion to roots in the way they support and absorb. There are other differences but they are not universal for all mosses. However the presence of clearly differentiated “stem” and “leaves”, the lack of deeply lobed or segmented leaves, and the absence of leaves arranged in three ranks would be the qualification of the plant being a moss.
Mosses also act as:
1. buffer against rainwater
2. increase humidity
3. produce oxygen
4. absorb CO2
5. absorb polluted rainwater through nitrogen compounds
6. absorb gaseous air pollution
7. provide an ideal environment for bacteria’s that break down organic
8. “eat” fine particulate matter
The following calculation explains the amount of fine particulate matter absorbed by moss:
A = busy thoroughfare = 14 gr/m2 yearly emissions of fine particulate matter
B = moss = 20 gr/m2 yearly absorption of fine particulate matter
A / B = 0.7 m2 moss is necessary for neutralization of fine particulate matter from 1m2 busy thoroughfare.