|Guatemalan archaeologists flanked by Professor David Lentz (left) and UC grad student Brian Lane (right) inside a temple.|
The UC team is the first North American team allowed to work at the Tikal site core in northern Guatemala in more than 40 years. The UC team is unique in other ways as well. Whereas previous archaeological excavations reflected an interest in culture history, particularly of the elites, researchers’ interests are different in the 21st century.
|There are several large water reservoirs surrounding the site of Tikal. Here, Brian is taking a soil core from the Corriental reservoir, the southernmost of the major reservoirs, to see how deep it was.|
And what the UC team has learned by studying these processes is that the Maya, at least initially, were practicing good forestry management.
“They were not allowed to cut down what we’re calling the ‘sacred groves,’” says Lentz. “Then that changed during the Late Classic period with Jasaw Chan K’awiil — one of the greatest figures of prehistory. The Tikal Maya had been beaten up and had fallen to second-rate status prior to his ascendancy. Jasaw Chan K’awiil led an army to the heartland of a competing city, Calakmul, captured their ruler, bound him, brought him back and sacrificed him — and it totally reversed their fortunes in a very dramatic way.”
After that, the Maya rebuilt the city of Tikal in a way never seen before. They begin building huge temples that required considerable resources, especially large, straight trees whose wood could withstand the weight of tons of stone. Their choices were limited to two types of trees only.
|Nick Dunning, Vern Scarborough and David Lentz (l-r)|
“Sapodilla is soft when you first cut it, so it can be carved into beautiful, intricate shapes. Yet when it dries, it is as hard as iron,” Lentz explains. “Logwood, on the other hand, is like iron to start with and stays that way.”
Logwood often is very crooked and grows to much lesser heights — so the archways in the temples built with logwood were far less ornate. Temples 1 through 4 are quite large, with temple 4 having the largest lintels, the beams over the doorways. Temples 5 and 6 (built in the middle — the temples are not numbered in order of construction) are much smaller.
|Temple 5 was built in 768 to 780 A.D.|
So what led to the downfall of the Maya? Whether it was the gods’ displeasure or not, the answer came from the heavens.
“When you clear all the forests, it changes the hydrologic cycle,” says Lentz. “The world is like a flat surface with all the trees acting as sponges on it. The trees absorb the water. Without the trees, there is no buffer to stop the water from runoff. That causes soil erosion, which then chokes the rivers and streams. With no trees, you lose water retention in the soil or aquifers so the ground dries up and then there is less transpiration, so therefore less rainfall as well.”
In addition to using the trees as timber, the Maya also burned the trees, adding carbon to the air in the form of carbon dioxide. Trees remove carbon dioxide from the air and return oxygen in its place, thus cleaning and purifying the air.
|Temple 1 was built second, in 682 to 734 A.D., possibly completed after Jasaw Chan K'awiil's death.|
A UC research team, which will again include archaeologist Vern Scarborough and geographer Nick Dunning, will be returning to Tikal in February 2010. Some of the key questions that remain are how did the Maya control their water resources, when did the deforestation occur, what trees were used when, did the Maya plant large orchards and where were the sacred groves.
“We’re saying in the end they were unsuccessful,” says Lentz. “But they kept it going for several hundreds of years — so they must have done some things right.”
This research was funded by grants from WennerGren and National Science Foundation award #0810118.
|The UC team: Brian Lane (Anthropology grad student), Vern Scarborough, Ben Thomas (Geography grad student), David Lentz, Nick Dunning, Eric Weaver (Geography grad student) and Kim Thompson (Biological Sciences grad student).|
Read more about Professor Lentz and his work:
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