We have a lot in the world to thank plants for, that which is the product of phytogenesis. Food, Fiber, Medicine, Oxygen, shade, shelter, aesthetics. But more often than not we don’t give plants the love they deserve. The whole worlds plant resources have been exploited, particularly in the last 200yrs and continue to be despoiled and degraded today. In Australia, where I am based, 70-90% of the country has been deforested and the myriad environmental problems we are facing can probably be ameliorated with plants and a concerted effort on our part to rebuild ecosystems and demonstrate reciprocity with the earth.
I am profoundly interested in all aspects of plants and the relationships between plants and people and ecology. From an airy-fairy science perspective, down to the nitty gritty of seed collection and food preparation. Expect varied posts on a range of plant topics. I will also be working on my science communication skills and trying to make this accessible to all, especially when I’m dealing with important issues that scientist have squirreled away in jargon.
Today I was reading about the environmental problems that Australia is facing due to deforestation. When trees are removed from an environment it drastically changes the whole ecology. Some examples of this are with keeping the salty water table at bay. After the second world war vast tracts of land in Western Australia were cleared for farming. However, the bushland that grew in these areas had extensive root systems that worked year round sucking up and transpiring (tree sweating) the water up from the ground. This has the effect of keeping the water table low as the water is wicked up from the ground and into the atmosphere and stored in the plants. Which wheat planted on the land much less water was wicked away because it is an annual and so dies each year rather than growing year after year like Australian perennial trees and grasses. When the water table rose it brought with it the salts and minerals that had pooled in the lower aquifer and this makes the land unusable for nearly any plants. CSIRO land and water estimate that we need to plant 7 billion trees in this region by 2020 to stop the land crossing a tipping point and becoming too salty for any plants.
In addition to keeping water tables low, forests alter the amount of water entering and ecosystem and moderate the temperature. Having a stand of forest with leaves provides a cool surface which water vapour in the air can condense onto, causing rain. In addition, plants like the blue gum, release compounds into the air that cause precipitation. Once trees have caused it to rain once, the same water is transpired by the plants and then precipitates again, with about 20% less water. Given the large scale tree clearing on this land is it any wonder that its drying up?? However, the good news is if we can begin land revegetation we can rebuild ecosystems and this will have benefits for everyone. Jobs for tree planting, products from the polyculture (many different organisms in the plantations, rather than the monoculture tree farms we have now) including wood, oils, fibres, biomass, environmental benefits for everyone. Hell, we might even be able to get the murray flowing again.
I invite questions, comments, criticism and whatever else you wanna throw this way. Aloha and Mahalo.
PG
