If growing enough biomass would reduce the excess CO2 in the atmosphere why not grow more?

Answer 1

OK. Let's clear the rest of our grassland and woods to plant row crops (burning is the most efficient way). Then we will plow them, spray them with herbacides and insecticides and fertilizer, divert water to irrigate them and destroy all kinds of habitat.

Is that what you want? Do you hate the environment that much?

Answer 2

Although this idea has some merit, there are 2 problems with it.

First, there is a limit to the amount of biomass that we can add. Plant biomass depends upon sunlight. Once you've covered all the "empty" areas with plants, you can't really increase it much beyond that.

Second, when a plant dies and decomposes, it releases the carbon that it absorbed while it was alive. So there is no net absorption of carbon dioxide.

This doesn't mean that the idea has no value at all. There are 2 ways that increasing biomass can help.

First, in areas where there isn't much biomass now (e.g. areas that were clearcut and not replanted), you can increase the amount of biomass if you plant now AND ensure that the biomass is replaced as it dies (e.g. you or nature replant when the next generation of trees dies). That will help at least a little.

Second, planting trees etc. will "buy some time" while we work on a more complete solution.

So increasing biomass is a good idea, but only if you understand its limitations and combine it with a long-term solution.

Answer 3

It may already be happening:

http://www.eurekalert.org/pub_releases/2004-06/bc-cfi061704.php

http://www.co2science.org/scripts/CO2ScienceB2C/articles/V8/N10/B1.jsp

It's not just the increase of number of plants, but in the mass of each plant that much of this excess CO2 is being taken up.

"Figure 19 shows the 30% increase in the forests of the United States that has taken place since 1950. Much of this increase is likely due to the increase in atmospheric CO2 that has already occurred. In addition, it has been reported that Amazonian rain forests are increasing their vegetation by about 34,000 moles (900 pounds) of carbon per acre per year (57), or about two tons of biomass per acre per year."
http://www.oism.org/pproject/s33p36.htm

It's amazing what the Earth is capable if we would quit trying to manipulate it more than we already have.

Say, for instance, we try to increase the growth of phytoplankton, as suggested. These photosynthetic don't simply die and "take the carbon with them to the bottom of the ocean / lake etc." Phytoplankton form the basis of the food chain for all marine organisms. That which isn't consumed by small animals will be consumed by bacteria - the end result is that a great portion of the CO2 will simply be released back to the atmosphere. When there is excess phytoplankton growth - a "bloom", this usually results in rapid bacterial consumption and subsequently oxygen - leading to massive killing off of marine animals by suffocation. Another danger is the release of toxins, as is the case of red tide.

We are well aware of the occurrence of these phenomena, although we're not totally clear on how it happens. Many times, humans cause it through excess agricultural runoff into lakes and oceans.

Patience may be the "man-made" solution for global warming.

Answer 4

There's a very similar question to this that was posted recently, you might also want to read some of the answers there. http://answers.yahoo.com/question/index;_ylt=AuJtehxljz2e6yLDTcakIH8S.Rd.?qid=20070721110020AAIAllZ

When answering I did a quick calculation (explained on the other question) and worked out that to offset our carbon emissions we would need to plant nearly one trillion trees.

I guess if we did that there'd be little room left for us - unless we started living in all the trees we'd planted.

Seriosly though, growing more biomass will certainly help offset carbon emissions and it doesn't have to be trees. Phytoplankton and algae are both excellent at removing CO2 from the atmosphere and when they die they take the carbon with them to the bottom of the ocean / lake etc. We could encourage the growth of these tiny plants at the same time as planting a realistic number of trees and implementing other naturally based solutions. Combined, such schemes could make a considerable difference.

Answer 5

It can help some. But it's not a complete solution. Look at how all the plants in the world are not remotely enough right now.

http://scrippsco2.ucsd.edu/graphics_gallery/mauna_loa_record/mlo_record.html

The little squiggles are nature doing its' thing. CO2 falls a bit during summer when plants are active, and rises during the winter.

Double the plant mass ( an impossible goal) and the rising curve slows down some, but that's all.

We also have to reduce greenhouse gases.

Answer 6

Where? And who will pay for it? Keep in mind you are asking this question in a world that allows millions of trees to be cut down in the Amazon every year.