May 21, 2017

Western Australia’s catastrophic forest collapse

A thoroughly lazy article below. It does seem to be true that West Australian forests are retreating but the galoots below have no idea why and don't try to find out. They just chant the tired old mantra of global warming. But global warming COULD NOT be the cause. As any number of studies show (e.g. here) increased CO2 in the atmosphere has a GREENING effect, not a browning effect. The writers below, George Matusick, Giles Hardy and Katinka Ruthrof, are all academics specializing in forest studies so they are quite simply a disgrace to their professions. It's just a bit of opportunistic Warmist propaganda below.

Even aside from its building block effects, elevated CO2 reduces transpiration time for plants and makes them less needful of water; Warming oceans give off more water vapor which comes down as rain.  So both CO2 rises and its allegedly associated temperature rises are good for plants.  They certainly don't dry anything out.  So what they say below flies in the face of all the facts.  They are just grant-hungry crooks


Recent, unprecedented, climate-driven forest collapses in Western Australia show us that ecosystem change can be sudden, dramatic and catastrophic. These collapses are a clear signal that we must develop new strategies to mitigate or prevent the future effects of climate change in Australian woodlands and forests. But society’s view of forests is ever-changing: are we willing to understand ecosystems and adapt to changing conditions?

The south west of Western Australia has experienced a long-term climate shift since the early 1970s, resulting in dryer and hotter than average conditions. This shifted baseline, or average, has also led to more frequent extreme events. In 2010, the region experienced the driest and second hottest year on record.

These climate changes have resulted in significant decreases in stream-flow and groundwater levels. For example, formerly permanent streams now stop flowing for considerable periods. Groundwater levels have fallen up to 11 meters in some forested areas, with larger decreases in populated areas. Clearly, soil water reserves have dried out substantially and will likely continue to do so; we are now starting to see the implications of this. Although most of the West Australian society, particularly those in urban environments, may be well-buffered from these changes, ecosystems are not.

The climatic changes occurring in the south west of Western Australia are contributing to deteriorating woodland and forest health. In the past 20 years, insect infestations and fungal diseases have plagued many iconic tree species, including tuart, wandoo, flooded gum, marri, and WA peppermint, increasing their mortality rates. Many of these disorders are likely triggered or incited by changing climate conditions.

In extreme climate conditions, woodland and forest health suffers most. For instance, during the record dry and hot period in 2010 and 2011, large patches of trees throughout the region suddenly collapsed, with little recovery in some areas. Along the coastal plain surrounding Perth, some areas of Banksia woodland suffered losses as high as 70-80%, while over 500 ha of tuart woodland collapsed and over 15,000 ha of exotic pine plantations (~70% north of Perth) were destroyed. In the northern jarrah forest, over 16,000 ha of forest suddenly collapsed, with mortality rates 10.5 times greater than normal.

In several ecosystems, species have died out and not been replaced, permanently shifting vegetation structure and ecosystem function. Some believe that species and ecosystems will transition slowly in response to climate change. But following the extreme conditions experienced in 2010-11, we now know the transition in many West Australian woodlands and forests will likely occur in sudden, catastrophic, step changes. Many species may not have time to adapt.

These often sudden and dramatic shifts in vegetation health, structure and function have profound consequences on associated flora and fauna, including many critically endangered species. The Mediterranean type-ecosystems of the south west were recently named among the top 10 ecosystems most vulnerable to climate-induced tipping points and degradation by a panel of 26 leading Australian ecologists. The region is one of 35 global biodiversity hotspots, harbouring approximately 1500 plant species, most of which aren’t found anywhere else.

SOURCE





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