Pine forests around Lake Grandy,
Grand County, Colorado, USA
Grand County, Colorado, USA
Ten hectares of the world’s forests are destroyed every minute, amounting to 4.9 million hectares a year. Between 1990 and 2005, 72.9 million hectares of forest vanished. Forests cover a total surface area of 3.69 billion hectares, or 30% of the Earth’s land mass.
These are the latest figures published by the FAO on 30 November 2011, which also reveal that the rate of net loss of forested land is speeding up, rising from 4.1 million hectares between 1990 and 2000 to 6.4 million hectares between 2000 and 2005.
These are the latest figures published by the FAO on 30 November 2011, which also reveal that the rate of net loss of forested land is speeding up, rising from 4.1 million hectares between 1990 and 2000 to 6.4 million hectares between 2000 and 2005.
Pests and infestations
are causing huge damage to forests. It is estimated that insect infestations
cause damage to around 35 million hectares of forested land each year,
especially in the temperate and boreal zones.
The phenomenon also affects Mediterranean European countries, as revealed in the European Commission’s Green Paper (I haven’t found the link) on the condition of Europe’s forests and the new challenges to be faced.
In southern Europe, where the availability of water resources is a critical issue, the increase in the number of summer droughts could lead to a decrease in the productivity and resistance of the forest system.
In Mediterranean countries, following periods of drought and the heatwaves of recent decades, plants have perished and numerous species of pine and oak have died out, phenomena generally attributed to drier and warmer weather and often associated with the proliferation of harmful insects and diseases.
With global warming now taking effect, plants that are already weakened by the dry conditions are an easy target for the more aggressive insects and pests. These are turning into an ever larger and increasingly resistant "army" as they are no longer killed off by cold winters and are often reinforced by "mercenaries" from other continents.
By way of example, in Switzerland, after the summer heatwave in 2003, the population of spruce bark beetle (ips typographus) increased enormously, damaging around 2.5 million m3 of spruce bark. Another pest that is rapidly spreading northwards and eastwards thanks to the warmer temperatures is the mountain pine beetle (dendroctonos ponderosae).
In the Sierra Nevada, southern Spain, the pine processionary (thaumetopoea pityocampa), a defoliator moth, is also attacking pine woods at higher altitudes.
More details:
http://www.ipcc.ch/pdf/assessment-report/ar4/wg3/ar4-wg3-chapter9.pdf
http://strengthenforests.com/coloradopinesstory.html
http://www.gcftaskforce.org/meeting/documents/Rebecca_Moore_Google.pdf (pg. 31 e 32)
http://www.waldwissen.net/waldwirtschaft/schaden/insekten/wsl_schluesselfaktor_insekten/index_IT
The phenomenon also affects Mediterranean European countries, as revealed in the European Commission’s Green Paper (I haven’t found the link) on the condition of Europe’s forests and the new challenges to be faced.
In southern Europe, where the availability of water resources is a critical issue, the increase in the number of summer droughts could lead to a decrease in the productivity and resistance of the forest system.
In Mediterranean countries, following periods of drought and the heatwaves of recent decades, plants have perished and numerous species of pine and oak have died out, phenomena generally attributed to drier and warmer weather and often associated with the proliferation of harmful insects and diseases.
With global warming now taking effect, plants that are already weakened by the dry conditions are an easy target for the more aggressive insects and pests. These are turning into an ever larger and increasingly resistant "army" as they are no longer killed off by cold winters and are often reinforced by "mercenaries" from other continents.
By way of example, in Switzerland, after the summer heatwave in 2003, the population of spruce bark beetle (ips typographus) increased enormously, damaging around 2.5 million m3 of spruce bark. Another pest that is rapidly spreading northwards and eastwards thanks to the warmer temperatures is the mountain pine beetle (dendroctonos ponderosae).
In the Sierra Nevada, southern Spain, the pine processionary (thaumetopoea pityocampa), a defoliator moth, is also attacking pine woods at higher altitudes.
More details:
http://www.ipcc.ch/pdf/assessment-report/ar4/wg3/ar4-wg3-chapter9.pdf
http://strengthenforests.com/coloradopinesstory.html
http://www.gcftaskforce.org/meeting/documents/Rebecca_Moore_Google.pdf (pg. 31 e 32)
http://www.waldwissen.net/waldwirtschaft/schaden/insekten/wsl_schluesselfaktor_insekten/index_IT
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Pine forests around Lake Grandy, Grand County, Colorado, USA
Image IKONOS © GeoEye, acquired on 9 June 2011.
The image shows one of the areas most badly affected by the mountain pine beetle (dendroctonus ponderosae): the image was created with the false-colour technique using an infrared band (RGB = 432), and shows the presence of vegetation in red.
Image IKONOS © GeoEye, acquired on 9 June 2011.
The image shows one of the areas most badly affected by the mountain pine beetle (dendroctonus ponderosae): the image was created with the false-colour technique using an infrared band (RGB = 432), and shows the presence of vegetation in red.