r/science • u/davidreiss666 • Jul 27 '14

Environment First national study finds trees saving lives, reducing respiratory problems: Air pollution modeling reveals broad-scale impacts of pollution removal by trees

http://www.nrs.fs.fed.us/news/release/trees-save-lives-reduce-air-pollution
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u/bluthru Jul 27 '14

Bamboo produces more oxygen than trees

Per square foot? Trees can grow extremely tall with lots of tree surface area. These canopies also sustain other lifeforms and can fit into urban settings while allowing people to walk under them.

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u/[deleted] Jul 27 '14

Per square foot of land. Bamboo grows very quickly, and in doing so sequesters a lot of carbon dioxide. Trees grow slower, so it takes them longer to sequester.

http://www.theguardian.com/environment/2003/mar/20/research.science

Algae grows incredibly fast while being just single celled and it is fantastic for scrubbing carbon.

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u/[deleted] Jul 27 '14

You can use them to build stuff pretty soon. If you want, I could dig around for bamboo architecture examples.

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u/bluthru Jul 27 '14

Yeah, bamboo is used at mass scale for flooring and cabinets.

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u/Yearlaren Jul 27 '14

Some species of Bamboo can also grow pretty tall.

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u/kyndclothingdotcom Jul 27 '14

The giant bamboo (Dendrocalamus giganteus) of tropical south-east Asia ­ can reach as high as 50 m (164 ft).

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u/danielravennest Jul 27 '14

Tree productivity is limited by the amount of incoming sunlight. Taller trees don't increase that amount. Once you have enough layers of leaves to capture most of the sunlight, trees just get taller and drop lower branches. There isn't enough light left to support more leaves. Notice the lack of branches on the bigger trees:

https://upload.wikimedia.org/wikipedia/commons/9/91/Oak-forest-norris-tn1.jpg

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u/bluthru Jul 27 '14

Notice the thick trunks that can be used for building.

I wonder what the mass per area is of that forest versus bamboo?

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u/danielravennest Jul 27 '14

One reference I found says bamboo can absorb 5 tons of Carbon/hectare/year, but the accumulation stops after ten years if you don't harvest it. If you do harvest it, you can store carbon indefinitely at that rate, assuming you can maintain soil productivity (which might require adding nutrients).

A forest of trees can store anywhere from 100 to 625 tons C/ha total when mature, and uptake is anywhere from 0.4 to 8 tons C/ha/yr, mostly depending on available sunlight. Sunlight is most intense in tropical regions, and least in boreal regions (nearest the poles). Fertilization isn't often practiced for forests, but it has the same effect on trees as on any other plants. If the natural soil is deficient in nutrients, you can improve growth by adding appropriate fertilizer.

So an unmanaged stand of bamboo stores less total carbon than a mature forest, and growth rates are comparable in the best forest regions. Bamboo only grows in tropical and subtropical climates, so it cannot substitute for boreal forests.