{"page":"\u003clink rel=\"stylesheet\" href=\"https://lessonplanet.com/assets/packs/css/resources-572d6a42.css\" /\u003e\n\u003clink rel=\"stylesheet\" href=\"https://lessonplanet.com/assets/packs/css/lp_boclips_stylesheets-f4d0de30.css\" media=\"all\" /\u003e\n\u003cdiv data-title='An ancient disaster uncovered in tree rings' data-url='/boclips/videos/5c54c046d8eafeecae149808' data-video-url='/boclips/videos/5c54c046d8eafeecae149808' id='bo_player_modal'\u003e\n\u003cdiv class='boclips-resource-page modal-dialog panel-container'\u003e\n\u003cdiv class='react-notifications-root'\u003e\u003c/div\u003e\n\u003cdiv class='rp-header'\u003e\n\u003cdiv class='rp-type'\u003e\n\u003ci aria-hidden='true' class='fai fa-regular fa-circle-play'\u003e\u003c/i\u003e\nVideo\n\u003c/div\u003e\n\u003ch1 class='rp-title' id='video-title'\u003e\nAn ancient disaster uncovered in tree rings\n\u003c/h1\u003e\n\u003cdiv class='rp-actions'\u003e\n\u003cdiv class='mr-1'\u003e\n\u003ca class=\"btn btn-success\" data-posthog-event=\"Signup: LP Signup Activity\" data-posthog-location=\"body_link_boclips\" data-remote=\"true\" href=\"/subscription/new\"\u003e\u003cspan\u003e\u003cspan\u003eGet Free Access\u003c/span\u003e\u003cspan class=\"\"\u003e for 10 Days\u003c/span\u003e\u003cspan\u003e!\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv class='rp-body'\u003e\n\u003cdiv class='rp-info'\u003e\n\u003cdiv aria-label='Hide resource details' class='rp-hide-info' role='button' tabindex='0'\u003e\u0026times;\u003c/div\u003e\n\u003ci aria-label='Expand resource details' class='rp-expand-info fai fa-solid fa-up-right-and-down-left-from-center' role='button' tabindex='0'\u003e\u003c/i\u003e\n\u003ci aria-label='Compress resource details' class='rp-compress-info fai fa-solid fa-down-left-and-up-right-to-center' role='button' tabindex='0'\u003e\u003c/i\u003e\n\u003cdiv class='rp-rating'\u003e\n\u003cspan class='resource-pool'\u003e\n\u003cspan class='pool-label'\u003ePublisher:\u003c/span\u003e\n\u003cspan class='pool-name'\u003e\n\u003cspan class='text'\u003e\u003ca data-publisher-id=\"30356011\" href=\"/search?publisher_ids%5B%5D=30356011\"\u003eCurated Video\u003c/a\u003e\u003c/span\u003e\n\u003c/span\u003e\n\u003c/span\u003e\n\u003c/div\u003e\n\u003cdiv class='rp-description'\u003e\n\u003cspan class='short-description'\u003eLam Dong province, 20 February 20091. Medium shot of Bidoup primeval forest2. Wide shot of forest3. Various of scientists and rangers walking in forest 4. Track shot close up of feet walking through forest 5. Medium shot of people...\u003c/span\u003e\n\u003cspan class='full-description hide'\u003eLam Dong province, 20 February 2009\u003cbr/\u003e1. Medium shot of Bidoup primeval forest\u003cbr/\u003e2. Wide shot of forest\u003cbr/\u003e3. Various of scientists and rangers walking in forest \u003cbr/\u003e4. Track shot close up of feet walking through forest \u003cbr/\u003e5. Medium shot of people walking among the trees \u003cbr/\u003e6. Wide shot of fokienia tree from below\u003cbr/\u003e7. Medium shot of fokienia branches\u003cbr/\u003e8. Wide of scientists looking up at a fokienia tree from below\u003cbr/\u003e9. Pan left from medium shot of fokienia trunk to scientists and rangers walking  \u003cbr/\u003e10. Low shot of Dr. Brendan Buckley walking towards tree \u003cbr/\u003e11. Medium shot of Dr. Buckley \u003cbr/\u003e12. Close up of Dr. Buckley's hand peeling back the bark from the tree \u003cbr/\u003e13. SOUNDBITE (English) Dr. Brendan Buckley, Tree Ring Laboratory, Columbia University \u003cbr/\u003e\"Fokienia is really the best thing we got out of this project from the tropics. Some of these trees are almost certainly a thousand years old. We've ring counted them nine hundred years. So we can say something about the past hydro climate variability really over the last millennium.\"\u003cbr/\u003e14. Medium shot of scientist marking tree\u003cbr/\u003e15. Close up of scientist's hands marking the tree\u003cbr/\u003e16. SOUNDBITE (English) Dr. Brendan Buckley, Tree Ring Laboratory, Columbia University \u003cbr/\u003e\"The imprint of climate, the regional climate here on these trees is strong enough reflected in the fokienia that were able to pick up the pattern of narrow and wide rings, and that's what enables us to cross date them. That is one side of it. The other side is that the pattern that you see is meaningful in a climatic sense.\"\u003cbr/\u003e17. Wide shot of scientists coring tree\u003cbr/\u003e18. Medium shot of Buckley holding coring tool by the trunk\u003cbr/\u003e19. Close up of the coring tool being twisted into the tree trunk\u003cbr/\u003e20. Close of Buckley's face as he operates the coring tool\u003cbr/\u003e21. Medium shot of Buckley operating the coring tool\u003cbr/\u003e22. Close up of the handle of the coring tool\u003cbr/\u003e23. Low medium shot of Buckley coring a tree\u003cbr/\u003e24. Medium shot of tree branches\u003cbr/\u003e25. Close up of coring tool being taken out of the tree\u003cbr/\u003e26. Medium shot of Buckley pulling out the core material from the coring tool\u003cbr/\u003e27. Various close ups of cores\u003cbr/\u003e28. Tilt down medium shot from Buckley to the core\u003cbr/\u003e29. SOUNDBITE (English): Dr. Brendan Buckley, Tree Ring Laboratory, Columbia University \u003cbr/\u003e\"Probably the one that seems to be getting a lot of the attention lately is the one around the droughts that we find in the late 1300s and early 1400s - there's two back to back droughts that are multi decadal scale. They tend to correspond to the time that is considered to be the demise of Angkor Wat, the civilization of Angkor. That is the significant find socially.\"\u003cbr/\u003e30. Various of Buckley and his assistant putting core into plastic tube \u003cbr/\u003e31. Medium shot looking up the trunk of a tree to the branches\u003cbr/\u003e32. Close up of a tree trunk\u003cbr/\u003e33. Close up of a new growth with three leaves on tree trunk\u003cbr/\u003e34. Medium shot of tree trunk\u003cbr/\u003e35. SOUNDBITE (English): Daniel Penny, University of Sydney - director of Great Angkor Project: \u003cbr/\u003e\"It seems to us that for possibly hundreds of years, Angkor had been struggling with the management of water resources. And that seems to us to be the key forcing mechanism in the weakening of Angkor as the capital of an empire and as a city. And there are of course a range of other geopolitical economic social pressures which we don't know and which we can't measure, which would have acted on Angkor, of course, as any state does. So these droughts would almost certainly have had an impact.\"\u003cbr/\u003e36. Zoom in through doorway on temple\u003cbr/\u003e37. Various of temple\u003cbr/\u003eAngkor is an important archaeological site in South-East Asia - and its one that holds secrets to the ancient city's collapse.\u003cbr/\u003eIt was believed the Khmer capital was abandoned because of invasions by Siamese forces. \u003cbr/\u003eBut now evidence from tree rings seems to point to climatic change that could have led to Angkor's downfall.\u003cbr/\u003eThe ruins of Angkor lie amid acres of forests. The UNESCO World Heritage Site contains the remains of what is possibly the world's largest pre industrial city.\u003cbr/\u003eNow it seems the collapse of Cambodia's great ancient city of Angkor may have been due to a massive drought 600 years ago - and not solely down to an invasion of rival Siamese forces as had been previously thought. \u003cbr/\u003eScientists, who went to search for ancient conifers in the central highlands of Vietnam, say tree rings show evidence of severe droughts in the region at the time of the fall of the empire.\u003cbr/\u003eDr. Brendan M. Buckley from Columbia University's Tree-Ring Laboratory in New York says that bands from the tree rings he and his colleagues examined show that Southeast Asia was hit by a severe and prolonged drought from 1415 until 1439, coinciding with the period during which many archaeologists believe Angkor collapsed.\u003cbr/\u003eFrom the city of famed temples, kings ruled over most of Southeast Asia between the 9th and 14th centuries. \u003cbr/\u003eThey oversaw the construction of architectural stone marvels, including Angkor Wat, regarded as a wonder of religious architecture.\u003cbr/\u003eWhile the 1431 invasion from Siam - what is now Thailand - has long been regarded as a main cause of Angkor's fall, archaeologists now suspect ecological factors played a major part in its collapse.\u003cbr/\u003eThe thickness of a tree's rings provides scientists with an historical record of a region's climate. Wet periods encourage tree growth, making rings thicker, while dry periods create thinner rings.\u003cbr/\u003eNarrow rings found here lasted for decades, marking the time of droughts.\u003cbr/\u003eBuckley, one of the world's top tree ring experts, has spent the past 16 years taking core samples from trees across Southeast Asia to build a record of the region's climate dating back hundreds of years.\u003cbr/\u003eThe data has helped identify at least four mega-droughts in Southeast Asia dating back 722 years.\u003cbr/\u003eThe Greater Angkor Project - run by the University of Sydney in collaboration with the French archaeological group Ecole Francaise d'Extreme Orient and APSARA, the body responsible for management of the Angkor World Heritage Park - concluded in 2007 that ancient Angkor had become unwieldy. \u003cbr/\u003eEfforts to expand rice production to support a population of 1 million led to vast deforestation, top soil degradation and erosion.\u003cbr/\u003eDan Penny, a University of Sydney researcher who is a director at the Greater Angkor Project, says the new findings on drought will help researchers gain a greater understanding of why the kingdom collapsed.\u003cbr/\u003eIn Vietnam, Buckley and his team of scientists from Columbia University, the U.K, Japan and the Philippines searched for ancient fokienia trees, a rare species that grows in Vietnam, Laos and southern China. \u003cbr/\u003eAfter coring the ancient trees - which are at least 700-800 years old in the Bidoup primeval forest located in Vietnam's central highland - the scientists then use laser cut or microtome to analyse the anatomical structure of the rings.\u003cbr/\u003eAncient fokienia often stand about 30 meter tall, its stump diameter is between 1.5 - 2 meters.\u003cbr/\u003e\u003c/span\u003e\n\u003c/div\u003e\n\u003cdiv class='action-container flex justify-between'\u003e\n\u003cbutton aria-expanded='false' aria-label='Read more description' class='rp-full-description' 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