Population, Development, and Environment on the Yucatan´ Peninsula: From Ancient Maya to 2030 Wolfgang Lutz, Leonel Prieto, and Warren Sanderson Editors RR-00-14 July 2000 International Institute for Applied Systems Analysis, Laxenburg, Austria Tel: +43 2236 807 Fax: +43 2236 73148 E-mail: [email protected] Web: www.iiasa.ac.at International Standard Book Number 3-7045-0138-7 Research Reports, which record research conducted at IIASA, are independently reviewed before publication. Views or opinions expressed herein do not necessarily represent those of the Institute, its National Member Organizations, or other organizations supporting the work. Copyright c 2000 International Institute for Applied Systems Analysis All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage or retrieval system, without permission in writing from the copyright holder. Cover design by Anka James. Printed by Remaprint, Vienna. Contents Introduction: Understanding Complex Population–Environment Interactions Wolfgang Lutz iv PART I: The Evolution of Yucatan´ 1 1 Social and Environmental Factors in the Classic Maya Collapse William J. Folan, Betty Faust, Wolfgang Lutz, and Joel D. Gunn 2 2 Socioecological Regions of the Yucatan´ Peninsula Eduardo Batllori, Federico Dickinson, Ana Garc´ıa, Manuel Mart´ın, Ivan Gonzalez,´ Miguel Villasuso, and Jose Luis Febles 33 3 Recent Population and Education Trends on the Yucatan´ Peninsula Amarella Eastmond, Ana Garc´ıa de Fuentes, and Juan Cordoba´ y Ordonez˜ 54 4 Maya Culture, Population, and the Environment on the Yucatan´ Peninsula Betty Faust and Richard Bilsborrow 73 5 The Performance of the Economy of the Yucatan´ Peninsula from 1970–1993 Juan Luis Pena˜ Chapa, Manuel Martin Castillo, and Juan Carlos Gonzalez Avila 108 6 A Conceptual Model of the Aquifer of the Yucatan´ Peninsula Miguel J. Villasuso and Renan´ Mendez´ Ramos 120 PART II: Modeling the Future of the Yucatan´ Peninsula 140 7 Future Population and Education Trends: Scenarios to 2030 by Socioecological Region Anne Goujon, Iliana Kohler, and Wolfgang Lutz 141 8 Integrated Dynamic Modeling: An Application for Tourism on the Yucatan´ Peninsula Patricia P.A.A.H. Kandelaars 173 9 A Dynamic Simulation Model of Population Impacts on the Environment: A Fisheries Model Lauren Hale 204 10 Land Use on the Yucatan´ Peninsula: System and Model Description and Land-Use Scenarios Leonel Prieto 228 Glossary 256 iii Introduction: Understanding Complex Population–Environment Interactions Wolfgang Lutz Gaining a better understanding of how human populations depend on fragile envi- ronmental conditions and limited natural resources and at the same time change the environment on which they depend is a great scientific challenge of our time. There is no simple formula for adequately describing these interdependencies. Whether a given ecosystem can support a certain human population is not simply a question of the size of the population – as is the case for the carrying capacity of animal pop- ulations. It also depends on the behavior, the stage of economic development, the technology, and even the culture and social institutions of the specific population under consideration. This is why one cannot make a universal statement about the maximum or even the ideal number of people that should live in a given territory. Similarly, the impact of the human population on the environment through defor- estation, water and air pollution, destruction of marine ecosystems, etc., depends not only on the sheer number of people, but on the production and consumption patterns of these people and, of course, on the frailty of the specific ecosystem as well. Does the high complexity of population–development–environment (PDE) in- teractions mean that nothing can be said about this issue and that it must be left entirely to the randomness of future evolutions that we do not understand and can- not influence? Such a conclusion seems unreasonable. Although we may not be able to find a global formula, we may well be able to document and analyze these PDE interactions in specific settings for which we have reasonably reliable em- pirical information. Such an understanding can be achieved through traditional descriptive analysis of past trends as well as through more formal computer-based modeling. Both approaches are applied in this report, taking the Yucat´an peninsula as a specific case study. The International Institute for Applied Systems Analysis (IIASA) has long been a leading international center in the field of global and intersectoral modeling. Founded in 1972, at the height of the Cold War, by an American–Soviet initiative to iv v enable scientists to work together on issues of truly global relevance using the new tools of systems analysis, IIASA soon became a center of what is usually described as global modeling. During the 1980s, global modeling went out of fashion because of strong and mostly well-justified criticisms that too-strong assumptions were be- ing made without a good empirical basis and that different parts of the world were simply too different to be covered by rather simple uniform equations. This change in the research paradigms was also reflected in IIASA’s scientific research agenda during the 1980s. Research groups returned to sectoral modeling in the fields of demography, energy, forestry, water, air pollution, etc. Within these sectors, much more meaningful and reliable models were developed that found much greater ac- ceptance by scientists around the world. In a way, IIASA’s research agenda became more like those of most academic institutions, in which science is compartmental- ized by discipline. The only problem with traditional research along disciplinary boundaries is that the real world is not compartmentalized into disciplines. For example, in the real world water systems depend on the consumption of water by people and on the water pollution caused by them. The health status of the population depends on changes in the natural disease environment and on food availability, among other things. Food availability in turn depends on the provision of clean water and a host of factors that depend on changes in the human population size, settlement patterns, and consumption preferences. How can we understand the processes of the real world if we always stop our analysis at disciplinary boundaries? During the late 1980s, we at IIASA became increasingly aware of these prob- lems, especially when we were asked to prepare some new crosscutting analyses in preparation for the 1992 Earth Summit on environment and development, held in Rio de Janeiro. But how could we do crosscutting research without falling into the traps of earlier global modeling? One promising option that we decided to pursue was to broaden the disciplinary focus while at the same time narrowing the geographic focus. We decided to do a truly comprehensive study of one spe- cific microcosm with excellent data and high population density – the island of Mauritius. Together with colleagues from the University of Mauritius and funding from the United Nations Population Fund (UNFPA), we studied this highly interesting island from all possible angles. The book documenting this study (Lutz, 1994) combines more traditional multidisciplinary analysis with interdisciplinary model- ing and alternative scenarios to 2030. The second part of the book, Understanding through History, includes chapters on topics ranging from the environmental to the demographic and political history of this small island in the Indian Ocean. The third part, Understanding through Modeling, tries to pull the different aspects to- gether by defining some of their interactions. Under both these perspectives, which vi together make up the PDE approach, the primary goal is to understand what has happened in the past and what is likely to happen in the future under alternative development paths. This kind of analysis is highly relevant for policymakers be- cause it can help to indicate the longer-term consequences of short-term political decisions while taking account of some of the most important interactions between population trends, economic development, and environmental change. This Mauritius study not only provided a comprehensive picture of the island’s history and alternative future trends, it also taught us many important lessons about how to use the new generation of intersectoral models to avoid some of the pitfalls of traditional global models. However, the very nature of this case study approach means that the findings cannot be applied directly to other parts of the world. To gain a better understanding of more general features of population–environment interactions, additional case studies have to be conducted in different parts of the world. For this reason, after the Mauritius study, IIASA chose to go to the Yu- cat´an peninsula, and from there we have now gone on to Namibia, Botswana, and Mozambique. Of course, IIASA is not alone in conducting case studies on population– environment interactions. In the process of organizing a session on population and environment at the 1997 International Population Conference (organized by the International Union for the Scientific Study of Population and held in Beijing), I identified more than 250 recent small-scale studies concerning population and the environment, most of which used an anthropological approach. After looking through this large number