Climate shift ‘killing US trees’


Old growth trees in western parts of the US are probably being killed as a result of regional changes to the climate, a study has suggested.

BBC News environment reporter Mark Kinver reports researchers as saying that analysis of undisturbed forests showed the trees’ mortality rate had doubled since 1955, researchers said.

They warned that the loss of old growth trees could have implications for the areas’ ecology and for the amount of carbon that the forests could store.

The findings have been published in the journal Science.

“Data from unmanaged old forests in the western US showed that background mortality rates have increased rapidly in recent decades,” the team of US and Canadian scientists wrote.

“Because mortality increased in small trees, the overall increase in mortality rates cannot be attributed to ageing of large trees,” they added.

“Regional warming and consequent increases in water deficits are likely contributors to the increase in tree mortality rates.”

After ruling out a variety of other possible factors, including insect attacks and air pollution, the researchers concluded that regional warming was the dominant contributor.

“From the 1970s to 2006, the mean annual temperature of the western US increased at a rate of 0.3C to 0.4C per decade, even approached 0.5C,” they observed.

“This regional warming has contributed to widespread hydrological changes, such as declining fraction of precipitation falling as snow, declining snowpack water content, earlier spring snowmelt and a consequent lengthening of summer drought.”

The team, led by the US Geological Society (USGS), examined data from 76 temperate forest stands older than 200 years, which contained almost 59,000 trees.

Over the study period, which stretched back to 1955, more than 11,000 trees died.

The researchers reported that the increased mortality rate affected a range of species, different sized trees, and all elevations.

“The same way that in any group of people, a small number will die each year; in any forest, a small number of trees will die,” explained co-author Phil van Mantgem, a USGS ecologist.

“But our long-term monitoring shows that tree mortality has been climbing, while the establishment of replacement trees has not.”

The change in the forests’ dynamics, the team noted, was going to have an impact on the forests’ ecology and carbon storage capabilities.

“We may only be talking about an annual tree mortality rate changing from 1% a year to 2%, but over time a lot of small numbers add up,” said co-author Professor Mark Harmon from Oregon State University.

He feared that the die-back was the first sign of a “feedback loop” developing.

As regional warming caused an increased number of trees to die, there would be less living trees to absorb carbon dioxide from the atmosphere.

Yet there would be an increased proportion of decaying trees, releasing the carbon that had been locked away inside the trees’ wood.

Warmer temperatures might also increase the number and prevalence of insects and diseases that attack trees, the team added.

They used the example of recent outbreaks of tree-killing bark beetles in the US, which have been linked to a rise in temperatures.

Another member of the team, Dr Nate Stephenson, said increasing tree deaths could indicate a forest that was vulnerable to sudden, widespread die-back.

“That may be our biggest concern,” he warned.

“Is the trend we’re seeing a prelude to bigger, more abrupt changes to our forests.”

Source: BBC News website

Date: 23/01/2009


EU crack-down on imports of illegal timber


The European Union has taken steps to crack down on illegal timber imports, according to the European Commission.

On its website, the Commission said that illegal logging destroyed millions of acres of forest each year.

It warned that much of the timber ended up in Europe, one of the world’s largest markets for wood products like lumber, plywood and furniture.

About 20% of these imports came from trees that were illegally felled, it added.

Until now, the EU has promoted voluntary action to curb illegal logging. But under a new legislative proposal unveiled on 17 October, importers would have to take certain steps to verify the wood is legal.

The regulation would also apply to timber producers in the EU, where illegal logging has been reported in some countries.

Research shows that illegal logging is wreaking environmental havoc, accelerating deforestation, biodiversity loss and climate change.

Deforestation also accounts for almost a fifth of global greenhouse gas emissions.

The Commission warned that the problem was getting worse, adding that more than half of logging now occurred in vulnerable regions, such as the Amazon basin, central Africa, and south-east Asia.

In some countries, illegal logging is so rampant it far outstrips legal timber production.

Deforestation is expected to be a priority in the upcoming international talks on climate change. The Commission is proposing a global scheme to reward developing countries for cuts in greenhouse gases achieved by reducing deforestation.

The Commission’s website stated: “Illegal logging is not just a problem for the environment.

“It robs indigenous and local people of jobs and resources, and it fosters corruption and organised crime, with profits often used to fund regional wars.

“It also costs governments billions of euros in lost revenues and undermines the competitiveness of legal logging operations in both importing and exporting countries.”

Source: European Commission website

Date: 20/10/2008

Rich nations ‘must fund global forest preservation effort’


The international community should enable tropical forest nations to halve the rate of deforestation by 2020.

The assertion was among the recommendations made in an independent report commissioned by the UK prime minister.

The Eliasch Review, entitled Climate Change: Financing Global Forests, also said that industrialised nations should look to make the global forest sector “carbon neutral” by 2030.

Its main findings included:

  • Reducing emissions from deforestation should be fully included in any post-2012 global climate deal, which is expected to be struck at the key UN summit in Copenhagen next year.
  • National governments should develop their own strategies to combat deforestation in tropical forest nations.
  • Rich nations should provide financial support to establish the necessary mechanisms to deliver the goals of halving deforestion by 2020 and making the global forest sector carbon neutral by 2030.

The review estimates that the costs to build the necessary mechanisms will be up to $4bn over five years for 40 forest nations.

The review, headed by Swedish businessman Johan Eliasch, was set up by Gordon Brown in order to pull together a comprehensive analysis of the financing and mechanisms needed to support sustainable forest management and reduce emissions resulting from deforestation.

“Saving forests is critical for tackling climate change,” Mr Eliasch said.

“Without action on deforestation, avoiding the worst impacts of climate change will be next to impossible, and could lead to additional climate change damages of one trillion dollars a year by 2100.

He added that deforestation would continue for as long as cutting down and burning trees was more profitable than preserving them.

“Access to finance from carbon markets and other funding initiatives will be essential for supporting forest nations to meet this challenge.”

Mr Eliasch is Mr Brown’s special representative on deforestation and clean energy.

Source: Eliasch Review press release

Date: 14/10/2008

Indonesian province imposes deforestation ban


A province on the Indonesian island of Sumatra has pledged to stop destruction of its forests and peatlands in an effort to reduce carbon emissions from deforestation by 50% by 2009, Mongabay.com reports.

Riau’s governor announced the temporary ban, which will remain in place until signed into law, at a ceremony in the province’s capital Pekanbaru.

“The moratorium is an important first step and an opportunity for the local government, forest communities and other stakeholders to improve forest governance,” says Arief Wicaksono, Greenpeace Southeast Asia’s Political Advisor.

Curbing deforestation means the province will scale back plans to triple the area of land under oil palm cultivation.

Oil palm, which is used in the production of palm oil, is currently the largest driver of forest clearing in the province.

A study released in February estimated that deforestation of 4.2 million hectares of tropical forest and peat swamp in Riau over the past 25 years has generated 3.7 gigatonnes of carbon dioxide emissions.

Source: Mongabay.com

Date: 15/08/2008

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