Tree Loss & Climate Change

Catch-up TV is great. While away in the beautiful, deforested South Island of New Zealand, ABC TV Catalyst program screened "Tree Deaths" on 26 April 2012. Having just caught up with the program in ABCiView I am struck by the sad vision of acres of tree die-back in Western Australia. According to the program "We're looking at tree mortality over a scale of tens of millions of hectares in the last decade alone. "
Tree death is nothing new to landscapes such as Australia and New Zealand, where for years land deforestation has been the norm with consequent degradation of bio-diversity, erosion, water and carbon loss.
My ecology degree, many years ago, touched on the consequences of this type of loss.
I remember the problem of acid-rain and loss of trees in North America, Germany and other places, showing the environmental effects of atmospheric pollution. See http://www.greenfacts.org/en/forests/index.htm for more information on world forests.
So its not hard for me to see that temperature extremes coupled with increased evaporation may easily kill even well-adapted species (such as Eucalyptus) over a particularly short time span as documented in the program.
Mass kill events have been documented in other environments for example wide-spread coral bleaching in the Great Barrier Reef.
All this is secondary information to the climate change debate. It adds more dimensions to the problem.
The old chestnut, that increasing CO2 is good for plant growth, is not necessarily true for food crops and for forests. After all we have so changed the plant-based face of the planet and increased the population so much that this experiment with our base livelihood is really disturbing.

Near Alexandra, New Zealand-deforested and dry