“International Day for Biological Diversity”
FACTBOX-Animals, plants under threat from global warming
20 May 2007 23:04:37 GMT
May 21 (Reuters) – May 22 is the U.N.’s International Day for Biological Diversity, focused in 2007 on how global warming may drive many species of animals and plants to extinction.
Following are facts about the diversity of life on earth:
* Scientists have no clear idea of how many species — from algae to blue whales — live on earth. Estimates range from about 5 to 100 million. There are about 1.8 million named species so far.
* Humans are responsible for the worst spate of extinctions since the dinosaurs were wiped out 65 million years ago, according to a U.N. report in March 2006. It blamed destruction of habitats, expanding cities, pollution, deforestation, global warming and the introduction of “invasive species”.
* “Climate change is forecast to be become one of the biggest threats to biodiversity,” the U.N. Convention on Biological Diversity said in a statement marking May 22.
* “Approximately 20-30 percent of plant and animal species assessed so far are likely to be at greater risk of extinction if increases in global average temperature exceed 1.5 to 2.5 Celsius” (2.7 to 4.5 Fahrenheit), according to a report in April 2007 by the U.N. climate panel. Beyond that, it said ecosystems would face ever more wrenching changes.
* World leaders agreed at a 2002 U.N. summit in Johannesburg to “achieve by 2010 a significant reduction of the current rate of biodiversity loss at the global, regional and national level as a contribution to poverty alleviation and to the benefit of all life on Earth.”
* A global “Red List” of endangered species documents about 800 extinctions since 1500, from the flightless dodo to the Golden Toad of Costa Rica. Experts believe the real number is far higher.
* About 12-13 percent of the world’s land area is in protected areas but only about 0.5 percent of the seas.
“Driftwood … archives various kinds of data about climate, river flow, ocean and ice circulation, and other critical environmental and cultural characteristics … ”
Global and Planetary Change 47 (2005) 83 – 98
Deciphering the impact of change on the driftwood cycle: contribution to the study of human use of wood in the Arctic
Claire Alix, University of Alaska Museum, Fairbanks AK, USA; CNRS Paris 1 UMR 8096 bArche? ologie des Ame? riquesQ, France
Received 11 March 2004; accepted 29 October 2004
Driftwood that originates in the Siberian and North American boreal forest is the major source of wood to people in the treeless Arctic. It archives various kinds of data about climate, river flow, ocean and ice circulation, and other critical environmental and cultural characteristics in the north. Unlike wood in most other regions, it is often well preserved in arctic archaeological sites. The existence and renewal of driftwood are closely linked to specific climatic and ecological conditions that have changed through time (e.g., floods, river banks, storms, prevailing currents and winds, sea-ice circulation, etc.). These conditions differently affect the fall, circulation and delivery of driftwood to the coast, resulting in changes in abundance, distribution and intrinsic properties of the wood. Based on a review of existing literature supplemented by new data from Alaska, this paper details factors underlying the dynamic of driftwood production in terms of driftwood abundance and quality, and indigenous people’s use of the resource. Oral history interviews in coastal and river communities of Alaska recorded knowledge on northwest coast of Alaska and the south of the Chukotka Peninsula. Results show that the timing of treefall and river transport are crucial to the subsequent ocean circulation and may determine the size and quality of the wood. Ultimately, it conditions what coastal people could build or manufacture.
D 2004 Elsevier B.V. All rights reserved.
Keywords: Arctic; Alaska; driftwood; resource procurement; riparian system