Navigation Links
A quarter of the world's population depends on degrading land
Date:3/20/2009

March 2009 - A new study published in the journal Soil Use and Management attempts for the first time to measure the extent and severity of land degradation across the globe and concludes that 24% of the land area is degrading often in very productive areas.

Land degradation - the decline in the quality of soil, water and vegetation is of profound importance but until now there have been no consistent global data by which to assess its extent and severity. For nearly thirty years the world has depended on the Global Assessment of Soil Degradation (GLASOD) based on the subjective judgement of soil scientists who knew the conditions in their countries. GLASOD indicated that 15 per cent of the land area was degraded, but this was a map of perceptions, rather than measurement of land degradation.

The new study by Bai et al. measures global land degradation based on a clearly defined and consistent method using remotely sensed imagery. The results are startling. The new assessment indicates that 24 per cent of the land has been degraded over the period 1981-2003 - but there is hardly any overlap with the GLASOD area that recorded the cumulative effects of land degradation up to about 1990.

One of the authors, Dr David Dent of ISRIC - World Soil Information explains: "Degradation is primarily driven by land management and catastrophic natural phenomena.

Our study shows the extent and severity of land degradation measured in terms of loss of net primary productivity, making allowance for climatic variability. Overall, a quarter of the world's population depends directly on these degrading areas. The worst-hit areas are Africa south of the Equator, SE Asia and S China. The worst-affected countries, with more than 50 per cent of territory degrading are, in Africa, the Congo, Zaire, Equatorial Guinea, Gabon, Sierra Leone, Zambia and the most affected (95 per cent degrading) Swaziland; in Asia, Myanmar, Malaysia, Thailand, Laos, Korea and Indonesia. In terms of the rural population affected, the greatest numbers are in China, with nearly half a billion, India, Indonesia, Bangladesh and Brazil. The usual suspects, such as the African Sahel and around the Mediterranean are much less affected."

The resulting loss of carbon fixation from the atmosphere over the measured period amounts to a thousand million tonnes. At a shadow price of $50 per tonne, the loss of carbon fixed amounts to $50 billion and the real cost is far greater in terms of emissions to the atmosphere through loss of soil organic carbon.

Comparison with land use reveals that 19% of the degrading area is cropland and 43% forest. Cropland occupies 12% of the land area and forest 28%, so both are affected disproportionately.

The study found only weak correlations between degrading land and rural population density and with biophysical factors such aridity. The researchers conclude that more detailed analysis of land use history is needed to uncover the underlying social and economic drivers of land degradation.


'/>"/>

Contact: Samantha Holford
sholford@wiley.com
44-186-547-6269
Wiley-Blackwell
Source:Eurekalert

Related biology news :

1. BIO-key(R) Reports Profitability for Fourth Quarter and Full Year 2008
2. Aware, Inc. Reports Fourth Quarter and 2008 Financial Results
3. BIO-key(R) Announces Fourth Quarter and 2008 Year-End Earnings Release and Conference Call Schedule
4. Entrust Announces Financial Results for Fourth-Quarter and Fiscal 2008
5. Joslin research finds nearly three-quarters of youths with diabetes insufficient in vitamin D
6. bioMETRX, Inc. Highlights 3rd Quarter 2008 Financial Results
7. Orchid Cellmark Reports Third Quarter 2008 Financial Results
8. Communication Intelligence Corporation Reports Third Quarter 2008 Financial Results
9. Synaptics Reports Record Results for First Quarter of Fiscal 2009
10. BIO-key(R) Announces Additional $245,000 in Third Quarter Public Safety Orders
11. Synaptics to Report First Quarter Results on October 23
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/11/2017)... , Apr. 11, 2017 Research and ... Market 2017-2021" report to their offering. ... The global eye tracking market to grow at a ... report, Global Eye Tracking Market 2017-2021, has been prepared based on ... covers the market landscape and its growth prospects over the coming ...
(Date:4/5/2017)... YORK , April 5, 2017 Today ... is announcing that the server component of the HYPR ... known for providing the end-to-end security architecture that empowers ... HYPR has already secured over 15 million ... makers including manufacturers of connected home product suites and ...
(Date:3/30/2017)... HONG KONG , March 30, 2017 ... developed a system for three-dimensional (3D) fingerprint identification by adopting ground ... technology into a new realm of speed and accuracy for use ... applications at an affordable cost. ... ...
Breaking Biology News(10 mins):
(Date:9/20/2017)... ... ... Diversity focused business accelerator, The Refinery , announced today they are hosting ... technology-driven, women-led startups in Boston, MA, New Haven/Hamden, CT, and Newark, NJ. Fueling ... that week – in Boston, it will be part of the City of Boston's ...
(Date:9/20/2017)... ... September 20, 2017 , ... ... examining the effects of exoskeleton-assisted walking on gait parameters and neuromuscular activity ... "Neuromechanical adaptations during a robotic powered exoskeleton assisted walking session" (doi:10.1080.10790268.2017.1314900) was ...
(Date:9/20/2017)... Aurora, Ohio (PRWEB) , ... September 20, 2017 ... ... automation, systems integration, and building management solutions, announced today the opening of an ... customers in Taiwan and the Greater China region, while developing new relationships in ...
(Date:9/19/2017)... ... September 19, 2017 , ... ... group of funded early-stage tech companies. “Grit” author Angela Duckworth and her team ... the ic@3401 community is Cooley, an international law firm with decades of experience ...
Breaking Biology Technology: