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Bio­di­ver­sity


A Col­lec­tion of News by Moos


201316Nov14:52

Loss of for­est since 2000 largest in Indone­sia, recent study shows

Infor­ma­tion
pub­lished 16 Novem­ber 2013 | mod­i­fied 03 Novem­ber 2014
Archived

A new study based on Earth-​observing satel­lite data com­pre­hen­sively describes changes in the world’s forests from the begin­ning of this cen­tury. Pub­lished in Sci­ence on 15 Novem­ber, this unpar­al­lelled sur­vey of global forests tracked for­est loss and gain at the spa­tial gran­u­lar­ity of an area cov­ered by a base­ball dia­mond (30-​meter resolution).

Global forestchangeLed by Matthew C. Hansen of the Uni­ver­sity of Mary­land and assisted by USGS co-​author Thomas R. Love­land, a team of sci­en­tists analysed data from the Land­sat 7 satel­lite to map changes in forests from 2000 to 2012 around the world at local to global scales. The uni­form data from more than 650,000 scenes taken by Land­sat 7 ensured a con­sis­tent global per­spec­tive across time, national bound­aries, and regional ecosys­tems. An inter­ac­tive map of the results can be found here.

Track­ing changes in the world’s forests is crit­i­cal because forests have direct impacts on local and national economies, on cli­mate and local weather, and on wildlife and clean water
Anne Cas­tle, Assis­tant Sec­re­tary of the Inte­rior for Water and Science »

“This fresh view of recent changes in the world’s forests is thor­ough, objec­tive, visu­ally com­pelling, and vitally important.”

Over­all, the study found that from 2000 to 2012 global forests expe­ri­enced a loss of 888,000 square miles (2.3 mil­lion square kilo­me­ters), roughly the land area of the U.S. states east of the Mis­sis­sippi River. Dur­ing the study period, global forests also gained an area of 309,000 square miles (800,000 square kilo­me­ters), approx­i­mately the com­bined land area of Texas and Louisiana.

The global sur­vey found that Rus­sia expe­ri­enced the most for­est loss over­all (in absolute num­bers) over the study period. Brazil was the nation with the sec­ond high­est level of for­est loss, but other coun­tries, includ­ing Malaysia, Cam­bo­dia, Cote d’Ivoire, Tan­za­nia, Argentina and Paraguay, expe­ri­enced a greater pro­por­tional loss of for­est cover. Indone­sia exhib­ited the largest increase in for­est loss; its losses on an annual basis dur­ing 2011-​12 were twice what they were dur­ing 2000-​03.

Brazil is a global excep­tion in terms of for­est change dur­ing this time­frame, with a dra­matic policy-​driven reduc­tion in the rate of defor­esta­tion in the Ama­zon Basin. Brazil’s use of free Land­sat data in doc­u­ment­ing trends in defor­esta­tion was cru­cial to its pol­icy for­mu­la­tion and imple­men­ta­tion. To date, only Brazil pro­duces and shares spa­tially explicit infor­ma­tion on annual for­est extent and change.

In the United States, the most inten­sive for­est change was noted in the south­east­ern states where pine plan­ta­tions allow for cyclic tree har­vest­ing for tim­ber, fol­lowed by imme­di­ate plant­ing of tree replace­ments. In this area, over 30 per­cent of the for­est cover was either lost or regrown dur­ing the study period.

Video of global 30 meter res­o­lu­tion the­matic maps of the Earth’s land sur­face: Land­sat com­pos­ite ref­er­ence image (2000), sum­mary map of for­est loss, extent and gain (20002012), indi­vid­ual maps of for­est extent, gain, loss, and loss color-​coded by year:


Defor­esta­tion as well as delib­er­ate for­est regrowth are human fac­tors that accounted for most of the for­est change. Nat­ural forces – for instance, wild­fire, wind­storms, insect infes­ta­tions, and regrowth of aban­doned agri­cul­tural areas – also caused for­est changes, which were also method­i­cally mapped.

Per­haps an even bet­ter rep­re­sen­ta­tion on what is going on in our global forests is shown in the video of the Cli­mate Desk:


“Ever since the USGS made Land­sat data free to any­one in 2008, Land­sat imagery has served as a reli­able com­mon record, a shared vocab­u­lary of trusted data about Earth con­di­tions,” Cas­tle con­tin­ued. “It’s been said that the free data pol­icy is like giv­ing every per­son on the globe a free library card to the world’s best library on Earth observations.”

“With the free data pol­icy, we have seen a remark­able rev­o­lu­tion in the use of Land­sat for doc­u­ment­ing the changes in the Earth’s land cover,” said Tom Love­land, chief sci­en­tist at the USGS Earth Resources Obser­va­tion and Sci­ence (EROS) Cen­ter and a co-​author of the study. “This multi-​organisation project was only fea­si­ble with the exis­tence of free Land­sat data. The invalu­able Land­sat archive sup­plies high-​quality, long-​term, con­sis­tent global data at a scale appro­pri­ate for track­ing for­est gains and losses.”

Key to the project was col­lab­o­ra­tion with the Google Earth Engine team, who lever­aged sophis­ti­cated cloud com­put­ing tech­nol­ogy to enable Uni­ver­sity of Mary­land researchers to com­pute the vast amount of data in a mat­ter of days.

The 41-​year Land­sat record of changes on the Earth’s sur­face is con­tin­u­ously updated in the Land­sat archive main­tained by the USGS-​EROS Cen­ter in Sioux Falls, S.D.

Since 1972, the Land­sat pro­gram has played a crit­i­cal role in sup­ply­ing con­tin­u­ous, objec­tive data that can be used to mon­i­tor, under­stand, and man­age the resources needed to sus­tain human life, such as food, water, and forests. The Land­sat 8 satel­lite launched in Feb­ru­ary 2013 is designed to extend the four-​decade Land­sat record of Earth obser­va­tion. The Land­sat pro­gram is jointly man­aged by NASA and USGS.



(Source: USGS news release, 14.11.2013)


UN Biodiversity decade

Goal: 7000 tigers in the wild

Tiger range countries map

Tiger map” (CC BY 2.5) by Sander­son et al., 2006.

about zoos and their mis­sion regard­ing breed­ing endan­gered species, nature con­ser­va­tion, bio­di­ver­sity and edu­ca­tion, which of course relates to the evo­lu­tion of species.
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