Out of the past, in the present, and for the future of the Maya Forest

Anabel Ford and Keith Clarke


Contemporary communities of the Maya forest are pioneering lands and adapting to environmental conditions that have a long and dynamic tradition stretching back millennia to the ancient Maya civilization. While recent community land use patterns have emerged under different conditions, similar natural and physical resources shaped links that depend on an intricate interwoven alliance between culture and nature. Regardless of contemporary political boundaries, this region shares a common past, is united by the kindred present, and stands threatened by an ominous future. Current land use strategies are demonstrably unsustainable, and the accelerated deterioration of cultural and natural resources could be creating a situation of irreversible damage across the region at every scale. Without a clear appreciation of alternatives, the situation will persist. The El Pilar Program assembles a unique international multi-disciplinary research team that is drawn together by fundamental interests in the integrated science approach to conservation of the Maya forest. The research we are developing integrates cultural, physical, and natural science data on the development of one of the world's most biodiverse regions: the Maya forest. Importantly, our research is aligned with regional and local development activities in the Maya forest of Belize, Guatemala, and Mexico as coordinated with our international partners and in process at the recently discovered and newly declared protected area of El Pilar in Belize and Guatemala.

We are concentrating on the core area of the Classic Period Maya which includes the greater Peten region of the Maya forest incorporating the Usumacinta drainage of Mexico and Guatemala, northern Guatemala, states of Campeche and Quintana Roo Mexico, and Belize. Our research gathers together leading scholars and practitioners working with data pertaining to past human and natural systems, contemporary natural history, biogeography and ethnology, and predictive modeling and forecasting. Local and site-specific data collection are focused at the newly created El Pilar Archaeological Reserve for Maya flora and Fauna, where an innovative participatory conservation model has been founded. In addition, close collaborative relationships with the Consejo Nacional de Areas Protegidas (Guatemala), Government of Belize, as well as the Maya Forest Coalition (newly formed Feb 2001), Wildlife Conservation Society, and Conservation International play important roles in the research.

Figure 1: Regional, local, and site-specific areas of concentration in the Maya forest

To see larger picture, click on this image.

The goals of the research are focused on the creation of a regional model that accounts for the successful evolution of land use patterns of the ancient Maya at the local and site specific levels, models their demise, accounts for the creation of the contemporary Maya forest, and projects future scenarios based on community conservation models and population demography. Incorporated into our program is a strong international education component for students from the US and Maya forest region to participate in the site-specific research, investigation, and conservation. The education design leverages local and international community education awareness and participatory conservation-management programs around the El Pilar Archaeological Reserve of Belize and Guatemala.

Spatial/Temporal Complexity of the Maya Forest — Indigenous Maya or Indigenous Forest?

The Maya forest region is characterized by limestone ridges covered by a deciduous forest. This verdant jungle thrives on an annual rainfall of 1000-3000 mm mainly from June-January. A drought-like dry-season runs from January-June. Local activities are impacted by this wet/dry sequence today, as they were in the Maya prehistory.

A composite mosaic of regional land resources underwrites the foundation of Late Classic Period settlement distribution and intensity in the Maya forest. Settlement densities are the greatest in the well-drained ridges across the region. Ridge lands are concentrated in the interior and are characterized by shallow, fertile, mollisol soils of excellent quality, representing only 1% of the world's tropics yet up to 50% of the Maya forest. These soils are superior for hand cultivation methods but are inappropriate for industrial methods.

These well-drained zones preferred for Maya settlement are unevenly distributed across the region, resulting in dispersed settlement patterns. There is a distinct relationship between the availability of well-drained ridges, settlement density, and the regional Maya hierarchy. This is evident in the local settlement around El Pilar.

The ancient Maya occupation of the central lowland region can be traced back into the third millennium BC. The material archaeological record, however, is firm for the Middle Preclassic before 1000 BC. Steady settlement expansion typified the first millennium BC, based essentially on household farming decisions. In the Late Preclassic, around 250 BC, land use intensity diversified and civic-ceremonial centers made an appearance across the region. Settlements expanded over the area, focused initially on rivers, then lakes and, ultimately, spread across the entire interior area.

There is ample evidence that the interior Petén area around Tikal dominated the region in the Late Classic Period, AD 600-900. At that time, Maya settlement expansion and construction was at its maximum. Yet Maya cites do not fit traditional notions of urbanism, suggesting a value for "green space" that would allow for the forest garden. Even visual metaphors expressed values they placed on nature. Jaguars, three species of monkey including the Capuchin, locally extinct, and cacao figure prominently in Maya art and iconography. The presence of these animals has habitat implications for the Maya forest.

The centralization process was sustained through AD 900, when the Maya civilization "collapsed". Major administrative and political centers, such as Tikal in the central Petén, witness abrupt halts in public projects; but settlements persist through the Terminal Classic Period (AD 900-1000). Settlement evidence between Tikal and Yaxhá, in the Belize River area, as well as in northern Belize attest to persistent occupation. Further, monument building continued at El Pilar through this period, to cease in the Postclassic.

Many scholars focus on the dramatic Classic Maya collapse, we are most interested in the emergence and subsequent methodical growth of settlement and centers over more than two millennia, amply documented in the archaeological record, and stress the sustained and intensive land use strategies of the ancient Maya. The expansion of occupation and the evolution of social complexity of the Maya were based on gradual rise in population and concomitant land use intensification. Early investments in community development endured over time. This centralization process integrated the populations over a span of more than 1700 years, based on the development and management of the assets of the Maya forest. Environmental dimensions constrained subsistence strategies and cultural developments mediated those constraints.

Throughout the Maya sequence, there are a series of environmental factors that have been identified and interpreted through geological, paleoecological, tephrochonological, archaeological, and historical sources. For example, volcanic eruptions and intensity of volcanic activity in Mesoamerica is of particular interest in the evaluation of environmental inputs as local impacts and ability to distribute large amounts of volcanic ash to stratospheric levels have distinct impacts. The integration of all the distinct data sets into one comprehensive comparative base is critical in the understanding of the complex human and natural processes.

UCSB Maya Forest Geographic Information System

The University of California at Santa Barbara Maya Forest Geographic Information System (GIS) project has focused on assembling available data to cover the greater Maya forest region of Belize, Guatemala, and Mexico. The initial efforts have been supported by an innovative UCSB program called Research Across Disciplines and has provided the basis for our research at the regional level. These data are now combined into a regional GIS destined to be an archived database in the Alexandria Digital Library. Our compilation is based on the GIS developed at 1:250,000 by the Paseo Pantera Consortium for the US Agency for International Development. We have integrated our digitized maps of topography and soils, included Sader's (1999) land use data for the Petén, geo-referenced 11 MSS satellite images, incorporated the local GIS data base developed by Fedick (1989) for the Belize River area (topography, soils, geology, settlement), and included a 1998 1:6,000 photo-mosaic we developed of the El Pilar Archaeological Reserve for Maya flora and Fauna (EPAR). This first version that we have compiled specifically for the UCSB Maya Forest GIS has been shared with our collaborators in Belize and Guatemala.

We continue our interdisciplinary research, compiling the layered geo-reference data of the Maya forest derived from our biocomplexity team of investigators and collaborators from the region. The objective is to accurately document data from the region, from target local areas in Mexico, Guatemala and Belize, and to focus at the site-specific level for the El Pilar Archaeological Reserve Belize/Guatemala. The primary goal of the GIS data collection is to calibrate the evidential and agent-based land use models. The companion goal is to permanently archive the synthetic database for use by regional and international scientists. Working with established cooperative agreements with international partners, we will be expanding our site-specific comparative research to Mexico in association with Nigh of CIESAS, Turner of Clark University, and Fedick and Gómez-Pompa of UC Riverside.

Data for the our research derive from a variety of distinct resources, and involve a significant effort in compilation, and selected efforts at fieldwork to develop the essential bases for the natural/human systems inquiry and analyses. Past environmental dimensions and archaeological resources are dispersed among research centers where common work is ongoing. Much of the contemporary data are gathered in the archives of the team investigators and collaborators, embedded in different GIS data sets across the Maya forest region, found within literatures of the diverse fields represented among the team, amassed in government agencies, university departments, and natural history museums and found in the gray literature from the development, management and community based non-government organizations that are found within the region collaborating with the Selva Maya Coalition. While most of the source materials are near at hand, the collection, incorporation, and development of a common shared GIS in consistent formats and common scales require significant attention. The following outline lists the data sets that are designed for incorporation into a comprehensive GIS to be developed in our research and analyses.

Data Out of the Past

Input-Scientists, their data and literature

Paleo-environmental (human-environment relations)
  • pollen records, sediment cores, and botanical remains
  • volcanology, tephrochronology and associated ash deposits and signatures
  • interpreted local, regional, and global climate history
  • architectural monuments
  • site survey and settlement transects
  • ceramics and stone artifacts
  • stratigraphy and chronologies
  • artistic motifs, inconographic representations of flora and fauna
  • Codices and interpretive accounts of the Maya
  • Military, Clerical and administrative accounts
  • Travelers and documentary accounts of the region

Data in the Present

GIS resources

Maya forest sources (mapping digitizing computer, existing GIS)
Scientists (published/analyzed scientific data)
  • brought by co-investigators
  • incompatibilities and regularities
Data sets-3 scales: Site Specific -GPS/transit/transects, Local -50K, Regional -1:250
  • critical: topo, soil, vegetation, hydrology, archaeological sites, political boundaries
  • additional: new satellite data, DEMs, land tenure, protected areas, vegetation change

Input-Scientists, their data and literature

Ethnological, and agroforestry data
Biological and botanical data
Settlement size and composition

Literature and Sheet Maps (Mexico, Guatemala, Belize)

Maya forest sources
Paleo-environmental reports
Archaeological reports
Geographic maps, volcanic ash flow distributions

Data for the Future

Weights of Evidence (WofE) and Agent Based (AB) Modeling

Site-specific data collection standardization
Local scale WofE and AB modeling: geographic/climatic inputs, human systems consumption
Regional scale geographic definition/predictive modeling for climate, natural and human systems

The Maya forest is considered a biodiversity hotspot, ranked second of 25 resources at risk by Population Action International (2000). There are more than 24,000 plants, 5,000 of which are endemic. Yet, data are accumulating that this same forest reveals a low alpha diversity 89-103 species of flowering plants greater than or equal to 1.5cm DBH per ha. and a low beta diversity index of similarity of 0.53-0.71. Given the high economic component, with up to 90% of botanicals listed as useful plants, we are asking what is the role of human systems in the development of the Maya forest, and what are the implications of this issue for the conservation of the Maya forest in the future? If human interventions prove to selectively high grade the species composition to favor their economic needs over 4000 years, what does this mean for the evaluation of the Maya forest? Flora and fauna now recognized to be at risk must have co-evolved with the ancient Maya. Revealing and modeling the complex biosystems relationships is the true mystery of the Maya forest.

Interaction and Change in the Tropics: Humans and the Environment

Holocene environmental change and human adaptation are critical themes that impact our interpretation of the evolution of tropical ecology, biocomplexity, and the nature of cultural interaction. The functioning and management of tropical environments in the past, their role in biodiversity, and their future in a world of expanding populations is shrouded with myth and generalization. The complexity of the biological and managed ecosystems of the tropics are constrained by moisture and soil nutrients but not by temperature. The elasticity of carrying capacity for human populations has been well demonstrated in the paleontological and archaeological record, as has a relationship with population density and land use intensity.

Figure 2: Contrasting land use models for the ancient Maya (Fedick 1989) and contemporary development (Jenkins et al. 1976). The triangle point indicates El Pilar

To see larger picture, click on this image.

Great environmental changes have been wrought on the landscape of today's tropics, and nowhere is this more evident than in lowland Mesoamerica. The Maya forest is the northernmost contiguous stand of the tropical forest. This biologically rich landscape was the location where the ancient Maya evolved a complex civilization creating a home to a population 3 to 9 times that of today. What were the environmental conditions of the Maya pioneers and what caused their demise after more than 3 millennia of sustained agricultural land use?

The complex interrelationship of humans and their environment is encoded in the archaeological settlement patterns left by the Maya, featured in the aesthetic of the elite, and linked to the geographic setting they depended upon. The demise of the civilization leaves a record of land use success, environmental failures, and succession that has the potential to be uncoded through an integrated science effort we and developing in the context of our research. By modeling ancient land use patterns across the Maya region and resolving the evidence at the regional, local and site specific scales, we gain an appreciation of the dynamics of system growth, the self-organizing tension of resilience, the triggers of phase changes, and the potentials for collapse. By compiling data at the same scales for the contemporary forest structure, known economic histories, and contemporary agro-forestry strategies, we can create an explanatory design for the devolution of the Classic Maya system into the present Maya forest. Future trajectories for the Maya forest at risk can be developed based on ethnological models of land use, social cognition and traditional practice, policy and land tenure industrial models for agriculture and climate change. The scenarios can be evaluated in terms of "best practices", using the ancient Maya development pattern and the traditional agro-forestry designs.

As a continuum, we are concentrating on the influences of climatic and environmental change on the one hand and the impacts of human population growth and land use practices on the other. This can be viewed over the entire temporal spectrum of the late Holocene as long-term trends, as well as more short-term events, influences, and interactions. Recognizing the dramatic changes that have transpired in the Maya forest region over the past 5 millennia — the local variations in rainfall regimes, regional stochastic impacts of volcanism, global dimensions of climatic change, as well as the pioneering, expansion, and rise of the Maya civilization — provides a foundation for re-evaluating the interpretations of the Maya prehistory, for understanding the regenerative processes of the Maya forest, and for developing conservation applications for the future. What have been the conditions for the maintenance of the Maya forest? If the co-evolution of the natural and human ecosystems is a fundamental quality of the Maya forest, how are the natural systems separated? What are the conditions of a sustained managed landscape? Are we assessing a feral forest, high-graded through a cultural selective process for economic species in the past and running a new course today?

Integrated Scientific Methods of Investigation

Our project applies both traditional areas of geographic theory and new predictive methods using weights-of-evidence (WofE) and agent-based modeling to the Maya case. Our Maya forest GIS database developed in collaboration with Belize's Department of Archaeology and Guatemala's Consejo Nacional de Areas Protegidas (CONAP), will be used as the basis for the weights-of-evidence (WofE) analysis and agent based models. We will be working with our wide collaborative base within to investigate geographic factors that contribute to the settlement intensity distributions of the ancient Maya. These in turn can be compared with proposed land use development strategies. Environmental components of our settlement location model will include soils, geology, topographic variables, and surface hydrology as predictor layers with known archeological Maya settlement locations as both actual and predicted locations in the WofE analysis. The strength of associations will provide ranks for environmental contributions to patterns that can be incorporated into the phase changes derived from agent based modeling.

The WofE origins are in mining geology and only recently have the essential tools been integrated into a GIS, ESRI's ArcView 3.2. Gary Raines, who helped build the ArcView extensions for WofE analysis has worked on the Columbia River Basin Ecosystem Management Project and in the development of GIS data standards (http://geology.usgs.gov/dm/). He has joined our group and is enthusiastically collaborating on this project. As developed, WofE analysis follows six steps: 1) select known points of some feature such as farming sites that are to be modeled, 1) select thematic maps that are suspected to contribute to the explanation of a distribution, 2) using the correlation analysis tools of WofE, convert selected map layers to binary or categorical form, 3) test for conditional independence comparing prior and posterior probabilities by class combinations, eliminating those maps which do not contribute explanatory power, 4) create a set of weights to use for each layer using Bayesian methods, and 5) develop posterior probability and the associated uncertainty maps using the weighted layers. The probabilities are then used as environmental weights in the agent based land-use model.

The ranking of Maya forest environment based on land use intensity in the Late Classic Period provides a basis for envisioning the Maya forest at the population peak. We are working to calibrate environmental data across the region, simulate inputs of rainfall change and volcanic ash falls based on tephrochronologies, model population growth and caloric needs, settlement dynamics of rise and decline, as well as dynamics of flora and fauna impact within the changing forest over time.

Specific Research Issues of the Maya Forest Region — A Creative Collaborative Direction

Out of the Past

Over 5000 years of change in the Maya forest there are the major features of climate, geological, population, settlement, and land use change. How can we identify the dynamics of the human/nature relationship by time periods that account for continuous sustainable Maya occupation until 1000 AD? While broad regional scale similarities are recognized, adaptive variability and distinct occupation chronologies are found across the greater region. What are the underlying commonalities and where do local and site-specific aspects account for differences across the region? There will be the environmental conditions and human dimensions that shape the differences. Can they be isolated?

Household farming strategies of the Maya evolved land use systems within the context of environmental dimensions of soil, topography, and water availability. How can management strategies account for resilience under rising population conditions over the trajectory of growth? Did human land use strategies impact sustainability? We know there were periodic environmental perturbations (drought, volcanic ash, and hurricanes) and that these had major environmental consequences. How were stochastic environmental changes accommodated in the record of the Maya forest? What were the opportunities and threats that may have occurred for human populations? How might the visual metaphors of the charismatic species (jaguar, macaw, and monkey) as documented in patronized art provide insights into ancient Maya resource conservation?

Once the data are collected, integrated, and calibrated, we will be in a position to work with the WofE and agent-based models. We strive to use the modeling process to identify key monitors of stability and change in the coupled human and natural systems of the Maya forest. We look at the process of devolution of the Maya civilization to model the succession of the regenerative forest processes based on the botanical data, alert to unknown behavior and environmental properties are emergent from our system model. Our collaborative efforts focus on the clarification of conditions that lead to the Maya forest of 1697 conquest up to the present.

Figure 3: The Maya house of Tzunu'un at El Pilar and its forest garden

To see larger picture, click on this image.

In the Present

It has been proposed that traditional human subsistence systems of agroforestry strategies recognized across the Maya lowlands and knowledge of the forest dynamics and resource potentials provide a basis for modeling land use in the past. This can be directly tested and used as a basis for the agent based models. This can assist in assessing human inputs of the ancient Maya model and the structure of the Maya forest today. We can examine the contemporary environmental inputs as predictors of the ancient Maya case and we can assess whether the traditional strategies are conservationist. We are particularly interested how the complexity of the traditional system can account for the biodiversity of the forest. In other words, are the ancient Maya model results compatible with the traditional forest garden strategies, dynamics and structure? This would help in understanding environmental links from the past to the present at the same time it captures lost environmental knowledge of traditional farming practices for the future.

These investigations address the essential qualities of the Maya forest biodiversity and its relationship to human systems. Working with forest gardeners employing traditional strategies in the forest today, we can see interplay and selectivity. In addition, the influence of propagation based natural and human influences on succession can impact long-term quality of the forest. Are these qualities related to the human character of management? What lessons can be drawn from an enhanced understanding of ancient Maya land use patterns that have implications for contemporary land use and settlement in the region and elsewhere?

For the Future

With 6 billion people on the earth today, and predictions of population doubling in the Central American region in the next 25 years, there is an urgent need to appreciate the human — environment relationship in order to promote conservation with development in the Maya forest. The threats to the integrity of the forest are palpable, loss of forest cover and immigration are correlates of the risks. The El Pilar Program has initiated an integrated regional science design for community participation in the conservation development of El Pilar. Coordinated with Non-Government Organizations in Belize and Guatemala as international partners, we have been using the El Pilar Archaeological Reserve for Maya Flora and Fauna as a hands-on educational laboratory for undergraduate and graduate training, local junior college field projects, community participation programs, and eco-archaeological tourism developments. This broad based educational platform uses the integrated science research (www.usgs.gov/integrated_science/summary.html) as a means to education on multiple levels. The success of this project has been recognized by the Rolex Awards for Enterprise (Anabel Ford Cultural Heritage 2000) and forms the foundation for our research on future models to enhance conservation in the Maya forest and beyond.

We use the El Pilar Program framework to promote the lessons we gather in from the research. We incorporate population data from Population Action International (CI 2001) in an effort to project the future of the Maya forest. We also use the predictive model of Classic Period Maya settlement to target potential areas for the replication of the El Pilar design to benefit long-term conservation requirements of the region. Our hope is that armed with knowledge and lessons from the past that we can project a best practices model for sustainable use and settlement in the Maya forest and other regions of the Central American tropical rainforest.

To see larger picture, click on this image.

Faced with the inevitability of more human inhabitants on our small planet, all need to accommodate food, shelter and procreation , the limits of our resources are at a critical threshold. In the past, we have relied on the resilience of the earth's system; the Maya forest prehistory is a case in point. But today's situation is different and the impacts of humans have reached global proportions. Resource management is one of the most urgent developments and alternatives to the industrial and technological strategies need to be seriously incorporated into our views of the future. With decreasing biodiversity and the focus on biological corridors to link forested environments, we need to draw attention to the nature of the human development corridors and how to make them more compatible with the ecosystem. Human landscapes simplify nature, transform environments towards economic and service roles, and divide culture from nature. A vital future must include an integration of nature and culture, where services such as family land stewardship, local soil development, regional watershed management, and global consideration work across scales and space. The understanding of the dynamics of the Maya forest provides a significant basis for developing an integrated approach to conservation as the ancient Maya sustained a system for millennia, experienced a collapse that certainly can provide insights into thresholds and phase changes in prehistory, and can demonstrate alternatives to current trends.

Further information can be obtained from the websites for the Maya Forest Alliance and the BRASS/El Pilar Archaeological Reserve.


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