In the quest to arrest and reverse the amount of carbon that we are dumping into the environment, we have come up with many different ways of trying to accomplish that goal. We know that we need trees, since they are the natural carbon trapping plant, in order to offset the carbon we keep pumping into the atmosphere and thus change the direction of the warming of our planet. A new study is now showing the truth of old wisdom to help combat global warming.
While it has been thought that just planting more trees would be enough, it seems that there is more to this natural equation than haphazardly planting trees. According to a study by Princeton University the key, as many old world gardener’s can tell you, is in the legumes.
Any amateur gardener can tell you, in order to have a thriving garden you need the sacred three elements in the soil: Potassium (K), Phosphorous (P), and Nitrogen (N). The reason that legumes are so important is that they help fix nitrogen into the soil in a symbiotic process with bacteria called rhizobia. Legumes create nodules in their root structure attacking rhizomes and engage in a symbiotic relationship; the legume provides carbohydrates for the bacteria and the bacteria, in turn, fixes nitrogen from the air into the soil. What the legume doesn’t use in its own growing process remains in the soil, where other plants can then take it up to grow.
In the process of trying to find more and more effective ways of combating global warming and climate change, one idea has been to reforest those areas of the equatorial rain forest in order to meet this need. This study goes on to show that the soil in the rain forest is very nitrogen poor, as most soils are, and that by planting more legume family trees ahead of other species in order to reforest the area. Applying some old world gardening wisdom in the scientific process is proving to be right and one of the better solutions.
In studying a second-growth forest in Panama, specifically an area that had been used for agricultural purposes for over 300 years, the researchers found that having legume trees present allowed the rapid growth of the forest in its first 12 years of recovery. In that short twelve year span the forest, which has grown on what was previously pasture land, has as least 40 percent of the carbon trapping function that is normally found in a mature forest.
Since legumes are so important in order to fix nitrogen in the soil, thus giving a huge boost to other trees, they have taken the spotlight as the beginning of real efforts in reforestation. It has been estimated that all the world’s forests took up and sequestered up to 2.4 quadrillion tons of carbon between 1990 and 2007, which lends a lot of credence to the idea put forward that we need to be more active in replanting as many trees as we can. More trees means more carbon taken out of the atmosphere, as well as more oxygen for everyone to breath, as well as all the other benefits, foods and materials, that trees bring.
However, this does not need to mean that we displace the human population for forest growth per se. We have an opportunity, as a species, to become stewards and wardens of our planet and the specific environment we find ourself. Having been endowed with a conscious, self-reflective awareness, it would seem that we have a direct responsibility to guide and shape our natural habitat, not simply exploit it for some short term gain. Just because we can rape and pillage does not mean we need to.
Also, with the understanding of the vast importance of legume trees to the process of reforestation, we have another tool to assist in the creation of more robust forests on a smaller scale. This would allow us to plan our urban landscape with the ability to sequester as much, if not more, carbon than a city can produce.
It is not just the ability of a forest to pull carbon out of our environment that is a perk, trees create micro-climates that are more conducive to both plants and animals. With the mass of concrete, steel, and asphalt that we find in our modern cities, trees can cool off and redirect a lot of that heat energy that can get trapped in these materials. It could help balance out the climate of a city to be more in balance with the rest of its surroundings which could have many more yet unknown benefits.
This understanding, this revelation, of the importance of legume trees in creating an environment for trees and plants to mature and grow as quickly as possible has a lot of potential. Whether it is in repopulating rain forests, or local forests, or even placing more trees into an urban environment, we may well have found a key. Some of this may seem like old wisdom, yet our current culture is such that until ‘science’ says its so, it isn’t completely actionable and this new study has proved what many already knew.
Written by: Iam Bloom