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Neotropical Forest Conservation, Agricultural Intensification, and Rural Out-migration: The Mexican Experience LUIS GARCÍA-BARRIOS, YANKUIC M. GALVÁN-MIYOSHI, INGRID ABRIL VALDIVIESO-PÉREZ, OMAR R. MASERA, GERARDO BOCCO, AND JOHN VANDERMEER

Forest loss in the tropics is one of the most critical contemporary environmental problems. Understanding the complex sociopolitical and ecological forces operative in producing this problem has thus become an important scientific mandate. Some recent literature has suggested that modern market economy trends in Latin America—namely, rural out-migration and policies strongly favoring high-input, industry-based agriculture— have helped curtail and sometimes revert the net loss of tropical forests, mainly through afforestation of land abandoned by smallholders. Government in Mexico, a megadiverse country with one of the biggest out-migration and remittance economies in the world, has excelled in applying free-market policies and in discouraging historical smallholder agriculture. Our analysis of Mexico’s development path and of recent deforestation and reforestation trends at the national, regional, and local levels shows that, contrary to expectations, net deforestation is still occurring, and that other development, agricultural, and reforestation strategies are needed. Keywords: forest transition, Mexico, development and conservation, out-migration, agricultural intensification

D

eforestation in the Neotropics is considered to be a

major contributor to biodiversity loss, ecosystemservices reduction, land degradation, and global warming. Researchers cite expansion of agriculture as the largest driver of deforestation in underdeveloped tropical countries (Morales et al. 2008). Recently, however, national and regional studies report the incipient recovery of forested areas in some regions (Rudel et al. 2005). Particularly in Latin America, spontaneous abandonment of agricultural production by small farmers in marginalized land is seen as one of the main factors behind deforestation reversal (Grau et al. 2003, Grau and Aide 2008). The inverted J-shaped form of forest-cover time series in some tropical countries (Rudel et al. 2005) reflects a shift in net deforestation to net tree-cover expansion; it is analogous in pattern to that observed in forest transitions resulting from the development of industrial capitalism in northern Europe and North America during the 19th and 20th centuries (Mather 1992). Some authors conclude that the loss of forest cover in many tropical areas may soon be reversed to various degrees (e.g., Mather 2001). Such a shift would require lower deforestation rates or forest recovery mainly involving secondary

forests and tree plantations, or both. Direct and indirect effects on biodiversity and ecosystems services are expected to be varied but significant (Hecht and Saatchi 2007). Other authors further suggest that the main driver of this forest transition in tropical countries is development (Rudel et al. 2005, Barbier et al. 2009). In using the term “development,” they implicitly or explicitly consider the interaction of a number of factors in assumed capitalist economies (e.g., population growth, quality of life, food demand, market exchange, industrialization, urbanization, agroindustry expansion, high-input land-use localization, rural out-migration, and proletarianization, among others). Mexico is especially suited for studies that advance our understanding of the complex relation between forest conservation, agricultural intensification, rural out-migration, and market-economy development (Galván 2008, Galván et al. 2009): Mexico is a medium-sized, megadiverse, semideveloped country with a complex agrarian history and high deforestation rates. After World War II, industrialization in Mexico was rapid, and urbanization was followed by severe and long-lasting economic crises. Mexican governments have been ardent followers of neoliberalism and have excelled in

BioScience 59: 863–873. ISSN 0006-3568, electronic ISSN 1525-3244. © 2009 by American Institute of Biological Sciences. All rights reserved. Request permission to photocopy or reproduce article content at the University of California Press’s Rights and Permissions Web site at www.ucpressjournals.com/ reprintinfo.asp. doi:10.1525/bio.2009.59.10.8

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November 2009 / Vol. 59 No. 10 • BioScience 863

Articles the application of such policies since 1984. Mexico currently has one of the highest out-migration and remittance economies in the world. In the next three sections, we critically review current ideas and research results concerning the hypothesis that forest transitions are inevitable consequences of market-based economies, driven largely by land marginalization or abandonment and rural out-migration. We then address three questions: (1) Is net forest recovery occurring in Mexico at the national, regional, or local levels? (2) How does Mexico’s development trajectory—that is, its urbanization and industrialization, agrarian and agricultural structure, and rural out-migration—explain the current deforestation and reforestation patterns at these different levels? and (3) Is it likely that forest recovery will occur in space- and timescales relevant for conservation? Answers to these questions will not only contribute to the further development of theoretical frameworks for forest conservation and rural livelihoods but also inform future policies and social action. The development hypothesis of the forest transition theory The development hypothesis was first presented, in different contexts, by Mather (1992) and Walker (1993), and has seen much theoretical elaboration since then (e.g., Rudel et al. 2005, Barbier et al. 2009). The forest transition model (FTM) in its current form posits two interrelated and reinforcing proximal economic drivers that induce marginalized agricultural land to be abandoned to secondary forest succession. Less profitable agricultural land is marginalized. In industrial and postindustrial market economies, there are strong incentives to commodify farm inputs and outputs. As societies adopt this scheme for adjusting consumer prices, and as farmers also adopt it and adapt to it, monetary cost-benefit considerations become more important for defining land use. Agroindustrial technology produces larger market benefits on higher-quality land. Thus, all actors involved in agricultural production and marketing tend to concentrate their resources on the best land available to them, and they intensify their efforts in terms of frequency of use, labor, and capital investment. Under these conditions, marginalized land is perceived as unprofitable and is consequently abandoned or cleared at a lower rate. This “localization” of high agroindustrial-input agriculture and the ensuing marginalization and abandonment of less-profitable land can occur at local, regional, national, and international levels. The process is thought to be a consequence of, and a contributor to, development. Exodus of the rural population. As demand for market agricultural produce grows for a number of reasons linked to market-based development, and as industry-based agriculture and agribusiness predominate, land differentiation and localization becomes stronger and extends to ever-increasing scales. Thus, legions of people who cannot profitably farm 864 BioScience • November 2009 / Vol. 59 No. 10

their marginalized land are pushed to and pulled toward labor markets in urban centers. The resulting urban and industrial growth reinforce the process, contributing to further development. Simply put, these two hypotheses propose that, separately or together, agroindustry-based intensification and localization and rural out-migration are related to forest conservation in the following ways: First, if the same amount of food can be produced on a smaller land base as a result of agricultural intensification, more land will be available for conservation, suggesting that the degree to which food can be produced on a smaller land base should be correlated with lowered rates of deforestation. Second, if deforestation is caused by rural people clearing forest for farms, the degree to which those people depart (move to cities) should also be correlated with lowered rates of deforestation and higher rates of afforestation of formerly denuded land. Free-market globalization and tropical forest transitions The current phase of globalization refers to the integration of countries and economies into international circuits of commodities, capital, labor, technology, and information in the context of what is now known as the “neoliberal consensus.” Trade liberalization policies and structural-adjustment reforms have opened up economies to international commerce and deemphasized the state in favor of market mechanisms to drive development. These policies include privatization of national institutions, elimination of tariffs and subsidies, and reorganization of banking and credit systems (Hecht and Saatchi 2007). Because the market economy is considered to be the main force that drives the abandonment of marginalized agricultural land, rural out-migration, and consequently deforestation and reforestation, it is assumed that globalization drives and enhances all these processes and their interaction at all scales, from the local to the global. It is also assumed that neoliberal policies will correct market distortions that could be delaying forest transitions in some tropical countries (Barbier et al. 2009). Some researchers who have studied forest transitions in focalized regions of Latin America (e.g., Grau and Aide 2008) clearly embrace the two-development hypothesis of the FTM, and conclude that (a) most conservation policy is largely driven by the unrealistic assumption that market forces generally result in ecosystem degradation; and (b) as the process of ecological transition is largely associated with the market economy and the free movement of people, goods, and information at the global scale, it will be enhanced by policies that facilitate migration and discourage noncompetitive production systems while favoring the growth of high-input, high-yield crops on the best agricultural land; (c) ecosystem recovery in marginal lands will be difficult when government or nongovernmental organizations subsidize the inefficient production systems of traditional agriculture, agroforestry systems such as shade coffee, and extensive ranching; and (d) rural-urban migration, land abandonwww.biosciencemag.org

Articles ment, and ecosystem recovery will reduce farmer pressure on biological reserves. Other researchers studying forest transitions in Latin American countries also see in globalization important opportunities for accelerating forest recovery (Hecht and Saatchi 2007). Yet they differ with Grau and Aide (2008) in the freemarket variables that more strongly drive the process, in the alleged need for rural depopulation, and in the type of forest covers expected and required for conservation. The FTM predicts that greater population density in rural areas would correlate with less or no forest recovery and with more deforestation. Research in Central America (Hecht and Saatchi 2007) shows that anthropogenic woodlands—modified forest remnants, secondary forest, agroforestry systems, abandoned pastures—expanded during Central American civil wars at the end of the 20th century and have persisted and expanded in highly populated areas where international remittances from rural migrants, rural wages in nonagricultural activities, and food imports were combined with agrarian reform, environmental education, and economic opportunities for sustainable forestry and agroforestry activities; moreover, these woodlands can provide important ecosystem services and habitat for wildlife. Unresolved issues and the need for more regional and local research Forest recovery in the Neotropics and FTMs are capturing the imagination, hopes, and research efforts of many ecologists and conservationists interested in solving the puzzle of reconciling human well-being and conservation. Yet, as most researchers acknowledge to some extent, there are many unresolved issues and we must better understand the complexities entailed in identifying the existence of forest transitions and the drivers and social and environmental consequences of them. More specifically, we need to better understand the nonlinear relations, trade-offs, conflictive agendas, and unexpected and unwanted results involved in the interactions among market economy expansion, land-use patterns, rural out-migration, and forest conservation in the context of neoliberal globalization. A few examples illustrate the point. Agricultural intensification. Angelsen and Kaimowitz (2001) directly and carefully addressed the question, When does the higher yield and profitability of industry-based intensive agriculture lead to greater or lower tropical deforestation? They critically reviewed a number of hypotheses related to the FTM, and showed that in the tropics, commodity booms will delocalize production and expand forest clearing and intensive land use deep into the marginalized land of small farmers at any environmental cost. They conclude that more often than not, industry-based agriculture in areas near forests induces further deforestation. Thus, the balance between possible negative and positive effects of the latter type of agriculture—acknowledged even by the most optimistic followers of the dominant FTM (Grau and Aide 2008)—is a difficult one. www.biosciencemag.org

The FTM assumes that high-input, industrial-based agriculture is more profitable with good land than with marginal land. Some authors

extend the argument to the idea that further localization and concentration on this type of agriculture at a global scale is the most productive, efficient, and environmentally sound path for food production (e.g., Grau and Aide 2008). That notion has been contested theoretically and empirically by researchers from a number of scientific disciplines (e.g., Pretty et al. 2006, Pimentel and Pimentel 2007, Beintema et al. 2008, Perfecto et al. 2009). Rural out-migration. Rural-urban migration is a historical trend

in most tropical countries (Grau and Aide 2008), but rural depopulation of marginalized land is not necessarily its equilibrium condition. Through circular migration, international remittances, and other means, significant rural populations persist in many cases, adjusting livelihood strategies to the adverse effects of neoliberal globalization without abandoning their land (Hamilton et al. 2003). Rural depopulation in tropical mountainous regions can sometimes lead to land degradation as terraces, irrigation systems, fire control, and invasive species control are abandoned, and rural institutions for sustainable production and management of common resources and externalities are weakened (García-Barrios R and García-Barrios 1996). Development and forest transitions. An analysis by the Food

and Agriculture Organization of the United Nations of forest time-series data from 139 countries concluded that nations with increasing forest cover, many of which have begun to experience forest transition, and nations with declining forest cover, most of which have not experienced a forest transition, differ from one another in per capita income and in the extent of forest cover (Rudel et al. 2005). Careful regression analysis by Rudel (1998) revealed the following: (a) The industrialization hypothesis is supported only for the period 1948–1963; (b) in subsequent periods, only the population growth variable was a significant predictor of forest cover changes, with decreasing amounts of variance explained; and (c) urbanization did not help explain variance in either case. Similarly, other authors (Angelsen and Kaimowitz 2001) have shown that the so-called environmental Kuznets curve, which posits the existence of a bellshaped relationship between per capita income and environmental degradation, yields limited and inconclusive statistical evidence of such a relationship. Thus, the statistical relation between averaged economic development indicators and forest transitions at aggregate levels is tenuous. Are most Neotropical countries heading toward full market-economy development? After World War II, the majority of nations in

the world were classified as developing countries, a term that is commonly understood to mean that those countries are on a slow yet inexorable path toward development, and therefore toward forest transition, according to the current FTM. Another general assumption is that the current free-market November 2009 / Vol. 59 No. 10 • BioScience 865

Articles phase of globalization is driving and accelerating development processes in most parts of the world (Rostow 1991). This view has been contested theoretically (Perfecto et al. 2009), and by recent analytical modeling of empirical time-series of economic and development indicators (Mayer-Foulkes 2010). The analytical modeling shows that by market economy standards, development, semidevelopment, and stagnation at the country level are distinct dynamical attractors generated since the first “great divergence” between the developed and the undeveloped worlds, and that the current global economic model tends to stabilize, or trap, stagnant and semideveloped countries in their current state. Only a few countries manage to cross the boundaries between these attractors (Mayer-Foulkes 2010). Other authors use institutionaldevelopment theory to analyze the social conflicts and cooperation strategies of the current globalized society. They cast doubt on the notion that current development schemes constitute the only option, or even the best option, for generating and sustaining long-term human well-being and conservation (García-Barrios R et al. 2008). A fruitful debate and synthesis requires further development of theoretical frameworks and more in-depth and embedded case studies at the national, regional, and local levels (Redo et al. 2009).

a little more than 60% by 2000; by the 1990s, Mexico had lost 90% of its original tropical rainforests, 70% of its tropical dry forests, and 50% of its temperate forests (Galván 2008). National as well as regional assessments of land-use and cover-change dynamics indicate that forest losses exceed forest gains. Based on forest cover maps for 1976 and 2000, as well as a review of land-use and cover change case studies, Galván (2008) and colleagues (Galván et al. 2009) assessed losses and gains in forest cover at national and regional levels. They found that between 1976 and 2000 at the national level, the amount of forest lost to deforestation and degradation was four and six times higher, respectively, than the amount of forest gained through revegetation and old-forest regrowth (table 1). Deforestation dominates in tropical regions, where expansion of the agricultural frontier by grazing and cultivation is the main driver of forest loss. Degradation is the dominant process in tropical highlands, where illegal extraction of trees and household consumption of wood are the most important proximate drivers. At regional levels for the period of neoliberal reforms (after the mid-1980s), about twice as much land was deforested than was reforested in most cases (table 2), and old-growth forest degradation was much greater than old-forest regrowth (table 3). While in some regions annual rates of forest loss have decreased in recent decades, in most of the cases those rates have increased (table 4). In short, Neotropical forests in Mexico seem far from constituting forest transition, both at the national level and in most of the regions studied. In the next two sections we explain possible reasons for this.

Forest cover losses and gains in Mexico Mexico encompasses 1,972,545 square kilometers (km2), roughly divided into three equal parts: deserts and semideserts, tropical mountainous ranges, and tropical lowlands. In Mexico, biogeographic features (e.g., wide latitudinal Table 1. Deforestation and revegetation in Mexico, 1976–2000. range, highly variable topograForest type phy) and evolutionary factors Temperate Tropical Tropical have combined to create the fifth Forest change forest rainforest dry forest Total most biologically rich country in Conversion to agriculture (km2) 41,205 27,848 60,420 129,473 the world. Tremendous cultural Deforestation (percentage) 12 25 23 18 diversity has evolved in parallel 13,873 6454 13,478 33,805 Reconversion from agriculture (km2) with this biological diversity. Revegetation (percentage) 4 6 5 5 Mexico is considered the birthplace of the major early civi–27,332 –21,394 –46,942 –95,668 Net forest change (km2) lizations of Mesoamerica and Net deforestation (percentage change) –8 –19 –18 –13 the source of important crops Ratio of deforestation to revegetation 3 4 4 4 and agricultural practices. It is Conversion of old-growth forest to 80,415 16,604 32,104 129,123 now home to 54 indigenous secondary forest (km2) groups, most of them marginDeforestation (percentage) 26 18 20 23 alized small farmers (Martínez Reconversion of secondary forest to 7335 2035 32,104 19,809 old-growth forest (km2) et al. 2006). Revegetation (percentage) 2 2 6 3 A number of authors re2) –73,080 –14,569 –21584 –109,233 Net forest change (km viewed in Galván (2008) have Ratio of deforestation to revegetation 11 8 3 6 found that forests, both temperate and tropical, originally Note: Deforestation is the percentage of deforested land relative to forest cover area in 1976, and includes covered half of the Mexican terchanges from old and secondary forest to agriculture. Revegetation includes changes from agriculture to 2 ritory, around 1 million km , secondary and old forest. most of which have now been Source: Based on data from Galván (2008) and on information from Velázquez and colleagues (2002), Mas lost. About half of the original and colleagues (2004), and Couturier (2007). cover had been lost by 1976, and 866 BioScience • November 2009 / Vol. 59 No. 10

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Articles Table 2. Deforestation and revegetation indexes between 1984 and 2005, by case study. Percentage deforestation to percentage revegetationa

Ratio of deforestation to regrowth

10.8/21.2

0.5

1986–2000

Forest type

Case study

Temperate

Guerrero et al. 2008b

Temperate

Garibay and Bocco 2007b

7.0/6.4

1.1

2000–2005

Temperate

Flamenco-Sandoval et al. 2007b Ramírez and Zubieta 2005b

8.6/4.0

1.9

1986–2000

0.5/0.2

3.3

1993–2003

Temperate Temperate

Period

Region

1.9/0.1

12.6

1990–2000

Tropical dry

Galicia and García-Romero 2007b Bray et al. 2004c

17.8/15.9

1.1

1984–2000

Tropical dry

Dalle et al. 2006c

11.8/5.6

2.1

1988–1997

Tropical dry

Roy Chowdhury 2006b

4.6/2.1

2.2

1987–1996

Tropical rainforest

29.4/15.7

1.9

1986–2000

Tropical rainforest

Flamenco-Sandoval et al. 2007b Porter-Bolland et al. 2007c

14.5/7.1

2.0

1988–2005

Tropical rainforest

Garcia-Romero et al. 2004b

59.6/1.2

49.3

1990–2000

Purepecha region, Michoacan Purepecha region, Michoacan Selva del Ocote, Chiapas Monarch region, Michoacan Izta-Popo, Puebla Zona Maya, Quintana Roo Ejido X-Maben, Quintana Roo Yucatan peninsula, Campeche, Quintana Roo Selva del Ocote, Chiapas La Montaña, Campeche Tehuantepec Isthmus, Veracruz

Drivers for deforestation High-input avocado crops High-input avocado crops Cultivation Cultivation Cultivation and grazing Cultivation Cultivation Cultivation

Cattle ranching, Cultivation Cattle ranching Cattle ranching

Note: This table includes 10 of 15 case studies analyzed by Galván (2008) and Galván and colleagues (2009), allowing estimation of deforestation to revegetation ratios for different forest cover types, regions, and time periods between 1984 and 2005. This time span corresponds to the period of neoliberal reforms in Mexico. a. Deforestation and revegetation figures are percentages of the forest area given in table 1. b. Changes are from old forest to agriculture, and from agriculture to old forest and secondary forest. In this case, forest includes old forest and secondary forest. c. Changes are from old forest to agriculture, and from fallow to old forest.

Industrialization, urbanization, agriculture, and rural out-migration in Mexico Small farmers living in environmentally restrictive agricultural land, in a highly scattered settlement pattern mainly in temperate and tropical forested regions, made up more than 65% of Mexico’s population before World War II (GarcíaBarrios R and García-Barrios 1996). During 1945–1970, import-substitution industrialization, known as the “Mexican miracle,” propelled rapid growth of urban centers and shifted the proportion of rural dwellers to urban population. During this period, industry-based, export-oriented agriculture flourished on the better lands and bigger properties, while millions of modestly subsidized small farmers using low-external-input technologies were seen as providers of cheap staple food, making it possible to keep urban wages low (Appendini 2001). Absolute rural population on marginalized land continued to grow slowly (figure 1), and outmigration to the United States was localized to a few rural zones (CONAPO 2005). The recurring economic and debt crises, which began in 1970, and the strict application of neoliberal policies since the mid-1980s slowed industrial growth; significantly increased rural and urban unemployment and poverty; opened frontiers to heavily subsidized, cheap US grains; reduced most subsidies to small farmers; and changed the Mexican www.biosciencemag.org

Constitution to promote land privatization and concentration (De Janvry et al. 1997). Starting in 1994, the government actively sought to further expand and localize industry-based agriculture and to discourage, outcompete, and eliminate small-farmer, self-sufficient agriculture. Marginalized farmers responded to these changes by developing a diverse array of survival strategies that increasingly included cyclical migration to the United States as wage laborers, in spite of serious risks and restrictions on border crossing (De Janvry and Sadoulet 2001). Absolute rural population continued to grow slowly; the part of the rural population reported as active in agriculture, although it has oscillated in the past few years, followed the same trend (figure 1). Mexico’s remittance economy, one of the largest in the world (Ratha and Xu 2008), is stabilizing the rural population in these areas rather than depopulating marginalized rural regions; it is also financing and reorganizing rural livelihoods, agriculture practices, and land-use patterns (Hamilton et al. 2003). A minority of small farmers have found international export niches (e.g., fair trade, organic, shade-grown coffee) or national markets (e.g., high-input horticulture and floriculture) for their products (Beinteima et al. 2008). In several regions, expansion of both subsistence farming and commercial agriculture continue to extend the agricultural frontier. In most cases, labor devoted to agriculture and November 2009 / Vol. 59 No. 10 • BioScience 867

Articles Table 3. Degradation and regrowth ratios for selected case studies.

Forest type

Case study

Temperate Temperate Temperate Temperate Tropical rainforest Tropical rainforest

Ramirez and Zubieta 2005 Guerrero et al. 2008 Galicia and García-Romero 2007 Flamenco-Sandoval et al. 2007 García-Romero et al. 2004 Flamenco-Sandoval et al. 2007

Percentage deforestation to percentage revegetation a

Ratio of degradation to regrowth

Period

6.7/1.3 19.2/8.6 0.0/0.9 9.0/0.0 27.4/3.7 22.6/0.0

5.31 2.24 0 — 7.44 —

1993–2003 1986–2000 1990–2000 1986–2000 1990–2000 1986–2000

Region Monarch Biosphere Reserve Purepecha region Izta-Popo National Park Selva del Ocote Tehuantepec Isthmus Selva del Ocote

Note: Deforestation and revegetation figures are percentages of the forest area given in table 1. Changes are from closed forest to altered forest, and from altered forest to closed forest. Altered forest includes open forest, fragmented forests, and young fallows.

income derived from it has diminished in relative terms, but land use has not diminished as much. Small farmers have adapted to labor shortages, lack of agricultural subsidies, and disruption of local cooperation schemes by (a) abandoning soil conservation and fire-control practices (García-Barrios R and GarcíaBarrios 1996, Román-Cuesta et al. 2004), (b) significantly increasing herbicide use (Buckles and Erenstein 1996, Tooke et al. 2005), (c) investing part of their migradollars (money sent home by migrant workers) in buying livestock or grasslands (Schmook and Radel 2008, Valdivieso 2008), and (d) leasing their land to big ranchers (Juana CruzMorales, professor, Universidad Autónoma Chapingo, Chiapas, personal communication, 12 June 2009). A recent meta-analysis of a smaller data set of Mexican regional studies by Rudel (2008) confirmed that woody Figure 1. Evolution of urban, rural, and primary sector population in Mexicover gains occurred in a few regions where co, 1900–2030. Primary sector includes urban and rural population in agrimigration was important, but where cattle culture, forestry and fishery. Localities with fewer than 2500 inhabitants are ranching did not offset the process of land considered rural. Data from 1900 to 1990 are from the library Raúl Baillères abandonment. Jr., Instituto Tecnológico Autónomo de México (http://biblioteca.itam.mx). In most cases, livelihood readjustments in Data from 1995 to 2005 are from population censuses and Encuesta marginalized rural areas have not slowed deNacional de Ocupación y Empleo (www.inegi.org.mx). Projected data forestation. Because urban population centers for 2010–2030 (shaded area) are from Consejo Nacional de Población near marginalized areas continue to grow and (www.conapo.gob.mx). rural populations are not diminishing, the demand for energy, food, and other goods that forests provide is increasing. The weakening of local rural are already menacing their existence (Taylor and Zabin institutions that regulate the use of these resources and ac2000). cess to them leads not only to unchecked exploitation of the forests but also to greater conversion of forests to agroinComplex scenarios of deforestation dustrial crops and plantations. Ecologically sustainable and reforestation: Two case studies community forest-management projects implemented by Processes more complex than the simple abandonment of several ejidos (villages with socially regulated land tenure to agriculture and the recovery of forests occur in Mexico; these prevent land concentration) and indigenous communities processes may involve recovery, but they may also involve in Mexico have been successful in some cases (Bray and further loss or degradation of forest cover. The outcome of Klepeis 2005). Unfortunately, imports of forest products deforestation and reforestation drivers in the current rural and disarticulation and privatization of communal property context in Mexico is extremely varied and cannot be re868 BioScience • November 2009 / Vol. 59 No. 10

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Articles Table 4. Meta-analysis of deforestation rates from case studies.

Forest type Temperate

Tropical rainforest Tropical dry

Higher mean annual forest loss rates?

Mean Standard change deviation Counts

Minimum-maximum mean annual forest loss rates (last period considered)

Causes for changes in loss rates

Yes

2.8

2.5

5

1.5–4.8

Expansion of crop areas, illegal logging

No

–0.6

0.3

2

0.1–0.2

Yes No Yes No

2.2 –0.2 0.6 –0.5

2.2 — 0.6 0.4

3 1 2 2

0.6–4.7 1.6 0.6–0.7 0.1–0.3

Land abandonment, protected areas, biophysical limits Expansion of cattle ranching and cultivation — Expansion of cattle ranching and cultivation Land abandonment, agricultural intensification, forest management, protected areas

Note: Case studies can report data for two forest types; in those cases, we consider one count for each forest cover class. Source: Synthesis of main findings from Galván (2008) and Galván and colleagues (2008).

viewed thoroughly in this article. Nevertheless, in the next section we briefly describe two cases derived from our own field research, in which neoliberal policies propelled significant land-use change by inducing international migration and discouraging or outcompeting small-farmer maize production. To a great extent their outcomes represent the most contrasting levels of land abandonment and secondary-forest revegetation in the country. They both show the complex relations between agricultural intensification, rural outmigration, land-use change, and forest conservation. They have in common severe forest degradation resulting from the weakening of previously strong social institutions for sustainable land and forest management, although the mechanisms leading to the degradation differed. We refer readers to recent case studies in other regions of Mexico that address similar complex relationships (e.g., Bray and Klepeis 2005, Schmook and Radel 2008). Of the 10 studies in Mexico for which data on deforestation and reforestation (table 2) are available, only one shows a favorable reforestation ratio, for the region known as Purepecha, located in Michoacán in central Mexico. This case therefore merits closer examination. Purepecha covers 6540 km2 in central Mexico. With more than 2000 years of settlement history, this indigenous area is densely populated and urbanized, with rural population representing about one-quarter of the total population. The urban population has recently increased, but this is mostly because populations in settlements previously classified as rural have grown so much that the areas were reclassified as urban. Rural migration to nearby cities has ceased to be substantial in the past two decades. Out-migration to the United States is clearly an important phenomenon, but it is not a new one. Early arrival of railroads facilitated important migration from the beginning of the 20th century, and the Bracero program (1942– 1964) and the Paricutin volcano eruption (1943) propelled even larger migratory flows (Rose and Shaw 2008). Significant land-use change has been observed in recent decades and has affected natural and anthropogenic forest cover. Agricultural land abandonment and secondary regrowth, expansion of avocado tree plantations, and the loss www.biosciencemag.org

and degradation of old forests are the main categories of change (see figure 2). Changes during the period of neoliberal globalization did not result from rural depopulation, but rather from a readjustment of rural economic activities and from the dual and contradictory effects of the localization of industrial-based agriculture. Two studies (Klooster 2003, López et al. 2006) found that, at higher altitudes, agricultural abandonment correlated with secondary-forest recovery, as predicted by the FTM. As a result of risky production, increasing soil degradation, declining maize prices, and growing maize imports from the US corn belt, maize and other crops were gradually displaced by forest-based, off-farm activities. This area is too cold for planting avocados, and properties are generally too small for livestock, which explains why there was much secondary growth in abandoned maize plots. However, despite the contraction of the agricultural frontier, households continue to use forests intensively for timber and fuelwood and for supplying thousands of forest-dependent microindustries (e.g., wood handicrafts, charcoal, or furniture), demanded by rural and nearby urban populations. Lack of effective institutions and technology for forest management has allowed the overexploitation and degradation of forests, which suggests that the fit to the FTM, while formally tight, is less than desirable. At lower elevations in the region, a commodity boom has taken place. Very high-input avocado plantations covering nearly 60% (approximately 70,000 hectares) of the cultivated areas yield 60% of all national avocado production (SIAP 2007) and account for almost all national exports of avocado. The return on agricultural investment is twice that of other production centers in Mexico. For former maize producers, conversion to avocado meant a high-return escape from the maize crisis, leading them to reactivate abandoned land but also to clear forest areas that had been marginal even for maize production. Between 1986 and 2000, nearly 38% of the avocado cultivated land expanded over previous maize plots, and a similar share came from secondary and old-growth forests (figure 2; Guerrero et al. 2008). Conversion of managed forest lands to avocado production has become an November 2009 / Vol. 59 No. 10 • BioScience 869

Articles important threat to some of the documented, sustainable, community forest-management systems in the region, such as San Juan Nuevo. Thus we see in Purepecha a seeming correspondence with the FTM at higher elevations, but with a concomitant rise in the use—and not necessarily sustainable use—of regenerating and old-growth forests. Extremely few communities have forest-management plans. But in the lower elevations, even though there was a clear signal that should have led to reforestation according to the FTM (abandonment of traditional maize farming), the result has been not only conversion to more intensive agriculture (avocado production) but also an expansion of that production into nearby forests, thus increasing deforestation yet further, which belies the FTM predictions. The second case refers to land-use change in the buffer zone of UNESCO’s Man and the Biosphere reserve in La Sepultura. Our research in this region (Sanfiorenzo 2007, AguilarJiménez 2008, Valdivieso 2008, García-Barrios LE et al. 2009, Trujillo-Vasquez 2009) describes in detail the following scenario: During the period 1960–1985, the fertile, rain-fed valleys of the Fraylesca region experienced the effects of a commodity boom. Most of the land owned by medium-sized farms was converted to intensive, high-industrial-input maize production, and the zone became one of the three major corn suppliers at the national level. Far from preventing the deforestation of the adjacent Sierra Madre forests, this conversion promoted it. Thousands of poor, landless farmers took advantage of the commodity boom to colonize and deforest the mountains using high-input, intensive maize production methods on extremely steep slopes with erodible sandy soils.

Figure 2. Land use/cover change dynamics in the Purepecha region (1986–2000). Thickness of the arrow indicates the magnitude of the transitions between classes in terms of absolute area. Numbers in circles indicate the percentage of gains (blank circles) and losses (gray circles) that a given transition represents for each class. Source: Based on data from Guerrero and colleagues (2008). 870 BioScience • November 2009 / Vol. 59 No. 10

At the end of the 1980s, the cost effectiveness of maize production started to decline, and small farmers began to introduce cattle. During the mid-1990s, commercial maize production became unprofitable. In one farmer’s terms,“Before NAFTA we would sell one ton of maize to buy two tons of fertilizer; after NAFTA, we have to sell two tons of maize to buy one of fertilizer.” Farmers reduced maize production to subsistence levels, started to migrate temporarily to the United States in 1994, and used part of their migradollars to buy cleared land, thus accelerating the shift to grasslands for cattle production (the cattle herd in some communities has doubled since 2000). This prevented a significant revegetation of abandoned maize plots (figure 3). To date, grassland continues to encroach into forests despite the area’s formal status as a reserve buffer zone. More important, cattle are grazing deep into the forest and preventing sapling recruitment for long-term forest persistence. In short, contrary to the predictions of the FTM, the sprawling of industry-based agriculture into the Sierra Madre, followed by a production crisis—generated by intensified US production—induced migration, a labor shortage, and cattle expansion in the mountainous buffer zone. This course of events caused severe forest loss and degradation and prevented land abandonment and secondary-forest regeneration. Uncoordinated government agencies with conflicting policies distribute small amounts of money to promote opposite policies in the buffer zone (e.g., support for each cow owned by ranchers and payments for community-level conservation of environmental services). Active tree protection and promotion has started only recently in a few localities, through very modestly funded collaboration projects between visionary farmers, conservation officers, nongovernmental organizations, and researchers (e.g., projects such as fire control, active reforestation, fodder tree introduction in open pastures, understory coffee and palm cultivation). Is expecting a market-driven forest transition a robust conservation strategy for Mexico? Current forest transition theory seeks to explain past and present deforestation reversals worldwide. The “development path” hypothesis most commonly used to explain incipient forest recovery in some tropical regions of Latin America suggests that the multiple feedbacks among urbanization, industrialization, market-oriented agricultural production, and industry-based agrotechnology tend to localize the most profitable agriculture in the best land, discourage marginalized land use for agriculture, and push and pull marginalized farmers toward cities; in consequence, deforestation is slowed, allowing for forest recovery in abandoned marginalized land. As a corollary, the promotion and development of a global free market can only accelerate the process. The facts of recent Mexican rural history do not seem consistent with the theory. Before and during the neoliberal globalization period, Mexico was intensely driven toward a market-based, urban-oriented economy. A dramatic, longwww.biosciencemag.org

Articles term shift in rural-urban population ratios has occurred, and national and international policies have been actively pursued to discourage marginalized agricultural production. Nonetheless, in the face of weak endogenous economic growth, the interplay between neoliberal policies and peoples’ responses to them has stabilized absolute rural population in marginalized land, and this number might remain stationary until 2030 (CONAPO 2006). Labordemanding practices have certainly been discouraged; families have diversified their activities, and the proportion of rural income derived from agriculture has diminished. Consequently, important land-use changes have taken place, but national, regional, and local studies show that defor- Figure 3. Land-use and cover change (1975–2005) in a sample of 101 plots cultiestation rates continue to increase in many vated at some point with maize in the upper El Tablón River basin, within the cases, and forest recovery cannot keep pace buffer zone of La Sepultura Biological Reserve. Plots were visited and mapped, with deforestation. Land abandonment is and owners were interviewed in depth in 2005 about the timing of and reasons but one among many options small farm- for successive land use/cover changes. Plots with revegetation are not heading ers have; the expansion of livestock and toward old-forest growth, but rather toward medium-term rotation with maize grassland seems to predominate, more so in and grassland. After 1996, no maize plot in the sample came from clearing the low- and mid-altitude tropics. forest. New deforestation for grassland is not included here, but encroachment For some, these conditions may be seen on forest margins has been observed. Source: Based on data from Valdivieso as transitory. Mexico is considered to be in (2008). transition to development, and consequently, according to the FTM, a significant forest transition current recession, international financial capital speculation, will eventually arrive. For those who see a virtuous causal increasing restrictions on migratory flows, lower incomes loop among the current economic-growth model, human from oil exports, and decreasing social expenditures for health well-being, reforestation, and conservation, the conclusion and education narrow the possibility that most Mexicans seems to be that global free-market policies need to be can be released from this trap. Moreover, fully developed urgently reinforced. market economies experiencing forest transitions are not We contend that there is a less optimistic, more realistic exempt from causing—and suffering from—very serious interpretation. The relations between capitalist market-based environmental and social problems that extend worldwide. economy, human well-being, industry-based agricultural Mexico’s semideveloped dynamical status might be a historlocalization, rural out-migration, land abandonment, and ical blessing in disguise, as it constitutes an opportunity and forest recovery are more complex than the FTM reflects a challenge for exploring alternative development paths that and allow for currently unpredicted, contrasting outcomes. can reconcile human well-being and sustainable ecosystem use Even if growth of the market economy were actually an and conservation. unequivocal driver of net reforestation, Mexico’s market Expecting forested areas to be depopulated, or setting aside economy still might not grow in the next decades, as required fortress-type reserves as a central strategy for these purposes, for land abandonment to lead to significant forest conseris not realistic, at least for Mexico. Mexico ranks fourth in the vation effects. Unlike the Asian tigers, which recently and sucworld for its number of biological reserves, which cover 10% cessfully negotiated their way into market-economy of the country’s land (Martínez et al. 2006). Yet most of its development, a number of sociopolitical factors have preforested reserves have relatively small core areas and densely vented Mexico, a semideveloped country, from crossing the populated buffer zones. The government devotes extremely threshold toward full capitalist growth (Mayer-Foulkes low budgets and staff to control resource extraction from core 2008, 2010). Mexican elites have accepted unfavorable inzones, and, more important, only minimal effort and reternational investment and innovation-transfer conditions sources go toward sustainable land management and matrix and neglected health and education, which together stymie development programs in buffer zones (Figueroa-Diaz 2008). endogenous growth and human capacity building within the In Mexico, human settlements are embedded at all scales country (Mayer-Foulkes 2008). in forested areas. Thus, reconciling conservation and liveliAccording to Mayer-Foulkes (2008), 75% of the Mexican hoods has to be done at the local and regional levels. Mexipopulation is stuck in a human-development trap. The can rural people have demonstrated for centuries that they www.biosciencemag.org

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Articles have the ingenuity to temporarily cope with major environmental and social threats to their livelihoods (Garcia-Barrios LE and García-Barrios 1992, Perfecto et al. 2009). The country’s agricultural and environmental knowledge and heritage span millennia, and recently hundreds of grassroots efforts have sprung up to develop sustainable land and forest management (Morales et al. 2008, Beintema et al. 2008) and restoration practices (Gonzáles-Espinosa et al. 2008) under restrictive conditions. With sufficient social and government support, and with proper human development strategies involving the active participation of rural people, Mexico’s society could meet the enormous challenges of slowing the growth of cattle ranching and reversing open grassland expansion; eliminating biocide-drenched monocrops; and building diversified, agroforested landscapes that can provide robust rural livelihoods, healthy food for urban populations, critical ecosystem services, habitat for wild species, and corridors for ecosystem reserves. Reducing urban consumerism, redefining rural-urban economic and power relations, and establishing “substantive cooperation” (García-Barrios R et al. 2008) for economic and social development are crucial for achieving these goals. Acknowledgments We thank Raúl García-Barrios, David Mayer-Foulkes, Juana Cruz-Morales, Robert Walker, Andrew Waterman, and three anonymous reviewers for very useful comments. This research project was funded by the Consejo Nacional de Ciencia y Tecnología (projects 51253 and 45636) and by the Consejo Nacional de Ciencia y Tecnología and University of California Institute for Mexico and the United States program (2008–2009). References cited Aguilar-Jiménez R. 2008 Análisis de los sistemas de producción bovina en la cuenca del río El Tablón, en la zona de amortiguamiento de la Reserva de la Biosfera La Sepultura, Chiapas. Bachelor’s thesis. Universidad Autónoma de Chiapas, México. Angelsen A, Kaimowitz D, eds. 2001. Agricultural Technologies and Tropical Deforestation. CABI, in association with Center for International Forestry Research. Appendini K. 2001. De la milpa a los tortibonos: La reestructuración de la política alimentaria en México. El Colegio de México and United Nations Research Institute for Social Development. Barbier E, Burgess J, Grainger A. 2009. The forest transition: Towards a more comprehensive theoretical framework. Land Use Policy. doi:10.1016/j.landusepol.2009.02.001 Beintema N, et al. 2008. International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD). Global Summary. IAASTD. Bray DB, Klepeis P. 2005. Deforestation, forest transitions, and institutions for sustainability in southeastern México, 1900–2000. Environment and History 11: 195–223. Bray DB, Ellis EA, Armijo-Canto N, Beck CT. 2004. The institutional drivers of sustainable landscapes: A case study of the “Mayan Zone” in Quintana Roo, México. Land Use Policy 21: 333–346. Buckles D, Erenstein O. 1996. Intensifying maize-based cropping systems in the Sierra de Santa Martha. Centro Internacional de Mejoramiento de Maíz y Trigo. Natural Resource Group Paper. [CONAPO] Consejo Nacional de Poblacion. 2005. Migración MéxicoEstados Unidos: Panorama regional y estatal. CONAPO.

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