Sprawling metropolis: The ancient settlement surrounding the main temple at Angkor is now known to be three time bigger than previously suspected. Complex irrigation structures are seen to fan out for 20 to 25 km beyond the main city.
Credit: Wikipedia
SYDNEY: Radar and aerial photography have helped experts build a detailed new picture of an intricately designed settlement stretching for many kilometres around the ancient Cambodian temples of Angkor Wat.
The research provides a timely warning, revealing how the complex engineering features of Angkor may have led to its downfall by disrupting the local environment.
"Our results show that Angkor, beyond the well-known temples, was a vast collection of interlinked water management devices such as canals and reservoirs interspersed with small, local temples and occupation features such as mounded areas and ponds," said Damian Evans, from the Spatial Science Innovation Unit at the University of Sydney in Australia.
Complex challenge
Archaeologists have been trying to map the boundaries of the sprawling agricultural environs of Angkor in Siem Reap province since the 1950s, but the ancient remains have been subsumed by modern residential and agricultural developments, complicating the task.
Evan's led a team of Australian, Cambodian and French researchers who cracked the problem by linking information from hand-drawn maps, ground surveys, airborne photography, and ground-sensing radar provided by the U.S. space agency NASA.
Many years of data crunching later, they were able to identify over a thousand previously undetected man-made pond structures and at least 74 long-lost temples, all part of a massive network linked by a single hydraulic system. The system likely provided Angkor's citizens with a stable water supply despite the unpredictable monsoon season.
Their findings are published today in the U.S. journal The Proceedings of the National Academy of Sciences.
Evans said the size and extent of land use in Angkor was sufficient to have profoundly impacted on the regional ecology. "In the new maps and the excavations… we can see what looks to be evidence of this - breaches in dykes and barrages, attempts to patch up the system and stratigraphies [sediment layers], which suggest chaotic flows of water."
Magnificent temples
"For over one hundred years the research focus at Angkor has been on the magnificent temples, and on the sandstone inscriptions that are often found with them," said Evans. It has only been with the collapse of the brutal Khmer Rouge regime in the 1990s and the opening up of local research centres that people started to "look beyond these great structures to investigate where it actually was that people lived, how they fed themselves, and so on."
Janice Stargardt a geographer from the University of Cambridge, in England, commented that the re-mapping of Angkor and its extensive hinterland was significant "not only as an exercise in improved mapping using the latest technology, but also because of their sharp focus on the ancient irrigation works, linear embankments and their consequences both for ancient agriculture and settlement patterns."
Experts now know that the medieval settlement surrounding Angkor – the one-time capital of the illustrious Khmer empire, which flourished between the ninth and 14th centuries – covered a 3,000 square kilometre area. The urban complex was at least three times larger than archaeologists had previously suspected and easily the largest pre-industrial urban area of its kind, eclipsing comparable developments such as Tikal a Classic Maya "city" on the Yucatan peninsula in Mexico.
It remains to be seen whether the engineering feats of Angkor were a cause, a symptom, or a result of the city's decline. "The new map at least tells us where we ought to be looking for the answers," said Evans.
with Agençe France-Presse
