Today is National Tree Day. The day we are meant to plant trees. Two days ago New Scientist published an article titled ‘Planting trees may create deserts’. It went on,
Planting trees can create deserts, lower water tables and drain rivers, rather than filling them, claims a new report supported by the UK government.
Indeed studies in WA have indicated that clearing regrowth in the Perth catchment could increase runoff to dams by 40 gigalitres. This would almost replace the need for the desalination plant?
According to ABC Online,
More than 300,000 green thumbs will descend on sites around the country today to participate in National Tree Day.
Organisers say they have been heartened by an increase of almost one-third in the number of volunteers planting trees and shrubs to restore biodiversity.
Yeah. There are some places that will really benefit from more trees. But let’s also recognise that too many trees can destroy biodiversity.
Michael Duffy makes some reference to this in his piece in yesterday’s SMH titled ‘Carr’s green legacy is a black mark’:
Creating a national park and then, as this Government has done, largely letting “nature take its course”, means this history stops. Gradually the vegetation thickens, the fuel load grows, the animal populations expand, and weeds proliferate. The park becomes a sort of toxic ecological volcano, spewing out fire, kangaroos, weed seeds, and feral animals such as wild dogs into the surrounding countryside. It takes a few decades to reach this point. A lot of our national parks were created in the 1970s and 1980s, which is why these problems started to become acute in the 1990s.
We can expect these problems to occur at Yanga, where (according to the station’s website) the environment of two endangered species – the Australian bittern and the southern bell frog – depends on keeping the red-gum forests open by logging, which will now cease.
Thanks to J.F. Beck at http://rwdb.blogspot.com/2005/07/killer-trees.html for alerting me to the piece in New Scientist.
Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.