UC pioneers research on environmental practices of ancient Maya

(Press-News.org) VIDEO: A UC team is unveiling groundbreaking research on the agroforestry and water-management practices of the Maya over a 1,500-year period. See this flyover of the Tikal site developed by the...
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Thousands of international researchers will attend the March 29-April 3 Society for American Archaeology (SAA) annual meeting in Sacramento, Calif., presenting research at more than 250 special sessions and forums dedicated to specific topic areas.

One of those special sessions is dedicated to examining University of Cincinnati research on ancient Maya agroforestry and water-management systems at Tikal, located in northern Guatemala. The ancient city was likely one of the most influential in pre-Columbian Central America. In 2009 and again in 2010, a UC team, led by paleoethnobotanist David Lentz, professor of biology, was the first North American group permitted to work at the Tikal site core in more than 40 years.

Others on that large, interdisciplinary team included Nick Dunning, professor of geography; Vernon Scarborough, professor of anthropology, and archaeologist Ken Tankersley, assistant professor of anthropology.

Specifically, the SAA symposium session will report on recent UC research related to

The forest resources required to build and sustain the urban center; The nature of its land use; The Maya's complex water-management system, consisting of a carefully designed array of canals and reservoirs, intended to conserve water during the annual dry season and to control/contain floodwaters during the rainy months.

This research breaks new ground in that it is the first to examine forest conservation and water-management at Tikal, a paramount urban center estimated to have had a population of perhaps 60,000 to 80,000 inhabitants at AD 700. (Previous research, decades ago, focused on the social elite and their monumental structures.)

The overall goal of the UC research is to assess the manner by which the ancient Maya harvested their diverse natural resources—especially water and plant communities—in altering the engineered landscape through time.

Mayan temple

Said UC's Lentz, "The goal is to understand how the Maya lasted as a highly complex society for well over 1,500 years in a tropical environment. Their resource needs from forests were very great because they used trees to construct monumental buildings, for the creation of plaster (which was a surface cover for buildings and roadways), for cooking and many other needs. They had a sophisticated, long-lasting management system that apparently began to go awry during the Late Classic period." (AD 600-770)

He added, "It was this environmental conservation and water management that led to prosperity of a very high magnitude for a long period at Tikal. Similarly, when the city abandoned its conservation methods during the eighth century and depleted its natural resource bases, this led to a host of changes, such as altered hydrologic cycle and soil erosion on a broad scale that ultimately resulted in environmental deterioration. That, in turn, contributed to changes in availability of food, fuel, medicinal plants and other necessities. Over time, the result was societal disintegration."

In fact, Tikal's 1,500 years of affluence declined dramatically in the ninth century, and by AD 900, the site was largely abandoned.



INFORMATION:

Nine presentations by UC researchers representing the fields of anthropology, biology and geography will constitute the SAA session on "Ancient Maya Agroforestry and Water-Management Systems." This research was supported by grants from the National Science Foundation, The Wenner-Gren Foundation, and the Alphawood Foundation.

Also presented will be a handful of additional session presentations by researchers from other institutions but based on the UC work at Tikal.

Among the research presented by UC at the Society for American Archaeology meeting's session on "Ancient Maya Agroforestry and Water-Management Systems" is

NEW BIOMASS STUDIES SHOW THAT TIKAL FORESTS WERE INSUFFICIENT TO MEET THE TIMBER AND FUEL NEEDS OF THE LATE CLASSIC MAYA
UC research has focused on gaining a greater understanding of agroforestry practices of the pre-Columbian Maya at Tikal through a study of the standing biomass (obtained via forest-inventory surveys coupled with satellite imagery) that compares the modern tropical rainforest to what was in place in ancient Tikal. Using pollen data, UC scientists have projected biomass assessments into the past to determine the availability of timber supplies for the ancient Maya. Among the fundamental questions answered by UC research: What was the total standing biomass available to the Late Classic Maya to meet their fuel, construction and other needs? What were the species of plants, both wild and domesticated, that formed the basis of subsistence and political economy? Were management techniques adequate to maintain sustainable use of forests over time? Results show that despite careful management of Tikal forests for many centuries, Late Classic populations outstripped the capacity of the forests to provided needed fuel and construction material in a sustainable way.
UC presenters: David Lentz, University of Cincinnati
Kim Thompson, University of Cincinnati
Angela Hood, University of Cincinnati
Kevin Magee, University of Cincinnati
Co-author: Carmen Ramos, Instituto de Antropologia e Historia de Guatemala

NEW INSIGHTS INTO HOW THE ANCIENT MAYA BUILT FOR WATER MANAGEMENT
Early settlement at Tikal made use of natural springs at the summit of the present-day ridge top where the city was located. UC research into the evolution of this landscape has determined that later, to accommodate a growing population, the seeps were capped and sealed (preventing access to them) by the massive construction efforts that resulted in sophisticated, man-made reservoirs, which were then filled by seasonal rainfall collection. The Maya carefully integrated the built environment – plazas, roadways, buildings – into a water-collection and management system. They collected literally all the water that fell onto these paved and/or plastered surfaces and sluiced it into the reservoirs.

In addition, UC research has determined that what were once thought of only as causeways to neighboring urban centers also served as dams to collect water into ravines. At least one of these was a coffer dam, an area set aside to hold water from a reservoir while that reservoir was cleaned. The new research also examines the means the Maya used to keep the water supply clean. These included sand berms, with the sand serving as a filtering agent. The presence of a sand-filtration system is a new discovery by the UC team.
UC presenters: Vernon Scarborough, University of Cincinnati
Christopher Carr, University of Cincinnati
Eric Weaver, University of Cincinnati
Co-authors: Liwy Grazioso Grazioso, University of San Carlos
Brian Lane, University of Hawaii

ANCIENT MAYA PRACTICED WETLAND AGRICULTURE
The ancient Maya city of Tikal lies near the southwestern edge of the sprawling Bajo de Santa Fe, a seasonal swamp. Ancient residential settlement was relatively dense along the flanks of the swamp and on islands of higher ground within it. It's long been debated as to whether the area was farmed. Archaeological evidence, as well as the study of soils, pollen and other "ecofacts," suggests that these residents were indeed engaged in agricultural intensification, in other words, wetland agriculture along the edges of the swamp. The nature of Maya activities within the central portion of the swamp, where the distribution and effects of water were more extreme, is still not as well understood.
UC presenters: Nicholas Dunning, University of Cincinnati
Christopher Carr, University of Cincinnati
Kevin Magee, University of Cincinnati
Co-authors: Robert Griffin, Penn State University
John G. Jones, Washington State University

NEW DISCOVERY SHOWS THAT ANCIENT MAYA AT TIKAL EXPERIENCED CONTINUAL VOLCANIC ACTIVITY AND ASH FALL
UC researchers will present strong, new evidence that the ancient Maya at Tikal experienced almost continual ash fall from volcanoes active in the region, volcanic events that affected everything from soil quality, health, water-management practices and even pottery. Because volcanic ash leaves little visible evidence of its presence in a wet climate with alkaline soil, it's never been known until now how pervasive volcanic activity and its effects were in Tikal. In finding and coring sophisticated, man-made, ancient water reservoirs at the site, UC researchers found evidence of heavy layers of volcanic ash that, over years, settled at the bottoms of these reservoirs, large plastered or flagstone-lined chambers used by the ancient Maya for 1,500 years. Because of its chemical composition, this ash can be pinpointed to volcanoes once active in Guatemala and El Salvador.

The effects of such continuous ash fall would have been mixed. Such ash makes for extremely fertile soil (thus supporting maize agriculture and population increases) and for ease in glazing pottery. However, it also plugs water catchment and storage systems and permanently shreds the human lung since such volcanic ash is actually very fine shards of glass. Radiocarbon dating, x-ray powder diffraction, petrography, magnetic susceptibility and particle-size analysis of sediments from reservoirs at Tikal indicate at least nine distinctive volcanic events during the early and late Holocene period.
UC presenters: Ken Tankersley, University of Cincinnati
Nicholas Dunning, University of Cincinnati
Vern Scarborough, University of Cincinnati

MOLECULAR GENETIC STUDY REVEALS ANCIENT AGROFORESTRY PRACTICES
The neotropical tree Manilkara zapota (also known as the "chicle" tree) has been a resource for the ancient and contemporary Maya. It's been hypothesized that the ancient Maya cultivated the tree as an important timber species and for its fruit and that this cultivation led to overall reduced levels of genetic diversity. Reduced levels of genetic diversity in a population are a sign of human selection and incipient domestication. Initial research efforts have focused on quantifying levels of genetic variation among the trees from the Peten region of Guatemala and describing genetic variation among subpopulations from diverse habitat types and histories. UC research has recorded diversity levels of M. zapota subpopulations in the region. The next step will be to compare the genetic diversity of these trees in the Tikal region to the genetic diversity of trees in locales outside the region.
UC presenters: Kim Thompson, University of Cincinnati
David Lentz, University of Cincinnati
Theresa Culley, University of Cincinnati

CASE STUDY: TERRESTRIAL CORING TECHNIQUES
Wet-soil cores are commonly used to provide historical environmental indicators, including data on pollen, spores and other plant materials. A case study is presented of a different coring technique that employs dry-land coring of rock strata and soil (within the ancient reservoirs built by the Maya at Tikal) in order to understand a continually changing landscape in conjunction with time-intensive data-collecting strategies, such as test pits. This study employed a dry-land coring device to better understand the water-management systems at Tikal, such as the capacity of reservoirs and how much water they held during different time periods. For instance, found by means of this coring technique was a deep, broad water canal cut into limestone constructed during the pre-Classic period (approximately 2,000 years ago) during a dry spell when the Maya increased means for water collection. Later, when abundant rainfall returned, they "decommissioned" the canal by filling it in with masonry.
UC presenter: Vernon Scarborough, University of Cincinnati
Co-author: Brian Lane, University of Hawaii

CHEMICAL TESTS LOCATE ANCIENT MIDDENS (TRASH HEAPS) TO REVEAL ANCIENT PLANT-USE PRACTICES OF THE MAYA AT TIKAL
The presence of phosphate (a chemical) in the soil generally indicates human activities in the past. Thus, it helps scientists locate treasure troves of cultural information, such as trash dumps and burials. In searching for phosphate concentrations around Tikal, UC researchers found three untouched and deeply stratified (in use over a long period) middens (trash heaps) containing stone, ceramics, charcoal and an abundance of seeds and nut shells. Analysis of these materials will provide researchers with new insights into the subsistence strategy and plant-resource needs of the ancient Tikal inhabitants.
UC presenters: David Lentz, University of Cincinnati
Nicholas Dunning, University of Cincinnati
Vernon Scarborough, University of Cincinnati
Co-authors: Eric Coronel, Brigham Young University
Richard Terry, Brigham Young University

BRINGING TIKAL PROJECT MAPS INTO THE ERA OF ELECTRONIC GIS
UC researchers have converted paper maps of the central 16 square kilometers of the archaeological site of Tikal, originally made from 1957 to 1960, into electronic format for use in geographic information systems. This will enable electronic modeling of the Tikal watershed and thus further understanding of how the ancient Maya managed critical water resources. By means of the project, the UC team also checked the accuracy of the original maps with a global positioning system. That GPS testing of the original paper maps, first made by University of Pennsylvania researchers five decades ago, confirmed that the original maps are extremely accurate and can be used as a trustworthy tool even today.
UC presenters: Christopher Carr, University of Cincinnati
Eric Weaver, University of Cincinnati
Nicholas Dunning, University of Cincinnati
Vernon Scarborough, University of Cincinnati

USING 3-D MODELING TO EXAMINE WATER-MANAGEMENT LANDSCAPE MODIFICATIONS AT TIKAL
The digitization of paper maps of the archaeological site of Tikal into a GIS format presents new opportunities to visualize and analyze data. Software provides the capability to convert a 2-D digitized map into a 3-D model. Using ArcScene software, two 3-D maps were made. One presents the Tikal area prior to Maya settlement. The other displays the Maya-modified landscape. In addition, UC researchers used ArcGIS software to create a basic hydraulic model to examine how these modifications contributed to water management, e.g., how much water was stored or how much water was absorbed into the landscape. The eventual goal is to create 3-D renderings and flythroughs that show Tikal at four distinct periods in its history.
UC presenters: Eric Weaver, University of Cincinnati
Christopher Carr, University of Cincinnati
Nicholas Dunning, University of Cincinnati
Vernon Scarborough, University of Cincinnati

Other UC research, not specifically tied to Tikal, will also be presented at the SAA meeting. These are

EARLY PRECOLUMBIAN AGRICULTURE
UC researchers will present recent evidence for agricultural origins and landscape modifications that accompanied the emergence of complex societies in Mesoamerica. Not only were plants brought into domesticated cultivation over a 10,000-year period, but forests were also restructured to provide optimum productivity to meet human needs. Data will be presented from archaeological sites in Belize, Guatemala and Peru. This presentation will serve as a tribute to the longtime professional contributions of Mary Pohl, a Florida State University researcher. In 2008, Pohl and UC's Lentz confirmed evidence of domesticated sunflower in Mexico — 4,000 years before what had been previously believed.
UC presenter: David Lentz, University of Cincinnati
Co-author: Joshua Englehardt, Florida State University

RECONSTRUCTING PLANT-USE PRACTICES AT CEREN, EL SALVADOR
Ceren, El Salvador, is the "Pompeii" of Central America. Volcanic ash resulting from volcanic eruptions provides excellent preservation conditions at Ceren and a detailed view of ancient Maya plant use and agricultural practices. UC researchers found an untouched ancient midden (trash heap) south of Ceren's center. The midden was perfectly preserved due to the protective coverage of ash. By comparing the contents of the trash heap to plant materials found in the remains of Ceren, an ancient farming village, UC researchers are able to provide a much fuller picture of agriculture in the region. For instance, UC researchers determined that manioc (cassava) was cultivated extensively – entire fields in fact, whereas it had been previously thought that manioc cultivation had been quite limited. In addition, the tree crops were much more diverse than previously thought.
UC presenters: Angela Hood, University of Cincinnati
David Lentz, University of Cincinnati

WETLANDS AND THE TRANSITION TO AGRICULTURE IN EUROPE
Excavations at the Early Neolithic site of Vashtemi, Albania, shed light on the transition to agriculture in Southern Europe. The first systematically recovered collection of plant and animal remains from about 6000 B.C. at the site provides the first glimpse into the environmental conditions that early farmers had to negotiate in this one-time wetland setting and the choices they made regarding land management.
UC presenter: Susan Allen, University of Cincinnati
Co-author: Gjipali Ilirian, Centre for Albanaological Studies

NEWARK'S GREAT CIRCLE INCORPORTED A "MOAT," USED FOR SYMBOLIC PURPOSES FOR HUNDREDS OF YEARS
Newark, Ohio, boasts the largest complex of geometric earthworks in the world. The most prominent feature of that complex is the Great Circle, an earthen circle 1,200 feet across and 15 feet high. The interior of the circle features a circular ditch that was built atop sand and gravel, thus allowing water to easily seep up into the ditch when rainfall arrived. It's likely the ditch was a response to cool, dry weather (when there is less rainfall) caused by continuous, powerful volcanic activity over a multi-year period in the 6th century. UC research not only proves that the ditch was indeed used for purposes of collecting water, radiocarbon dating and other tools employed by the researchers indicate that the ditch was in use until about 700 AD. That's about 200 years longer than previously thought.
UC presenters: Emily Culver, University of Cincinnati
Ken Tankersley, University of Cincinnati

THE EFFECTS OF 22 YEARS OF DIFFERENTIAL LAND MANAGEMENT POLICY ON THE ARCHAEOLOGICAL RECORD
From 1947 to 1969, Clarksville Base, located within the Fort Campbell Military Installation in southwestern Kentucky and northern Tennessee, served as an atomic weapons storage facility. Archaeological surveys of more than 2,000 acres of land inside of and outside of Clarksville Base examine how decades of land-management practices have affected the area.
UC presenter: Kevin Magee, University of Cincinnati
Co-author: Marianne Ballantyne, BHE Environmental, Inc.

MATERIAL CULTURE IN EARLY 20TH CENTURY OHIO
A systematic survey of an early 1900s rural homestead in southwestern Ohio explores how the one-time occupants expressed social identity through possessions and consumer choices.
UC presenter: Ethan Barnes, University of Cincinnati