Chapter 8 Expanding the North American Perspective— Mexico Heidi Asbjornsen Heidi Asbjornsen is an associate professor, University of New Hampshire, Department of Natural Resources and the Environment. Contributors: Robert Manson, Citlalli López Binnqüist, and Patricia Negreros­Castillo Robert Manson is a professor and Coordinator of the Functional Ecology Network, Institute of Ecology, Mexico National Board of Science and Technology; Citlalli López Binnqüist is a researcher, University of Veracruz, Center for Tropical Research; Patricia Negreros-Castillo is a researcher, University of Veracruz, Center for Tropical Research. Impacts of Climatic Variability on Mexican Agroforestry systems are gaining greater attention within Agriculture Mexico as one strategy for mitigating and adapting to predicted climate change. Work by Locatelli et al. (2011) identified agro- Based on national assessments, Mexico is expected to see forestry as a tool for adaptation, enabling poor rural families, temperature increases of 0.9 to 2.5 ºC by the year 2020, and communities, and watersheds to be less vulnerable to extreme it is very probable that, by the year 2050, the climate will be and erratic weather events by generating diverse environmental warmer by 2.0 to 4.0 ºC, especially in the central and northern and socioeconomic benefits. This contribution by agroforestry parts of the country (MENR 2007). Rainfall is expected to systems was also recognized in Mexico’s National Climate decrease as much as 15 percent in the central part of the country, Change Strategy, which serves as a guide for Mexico’s actions but the number of severe storms and the intensity of severe during the next 40 years (SEMARNAT 2013). This Federal droughts are expected to increase nationwide (MENR 2007). strategy targets the reduction of greenhouse gas emissions, and Mexican agriculture will be particularly vulnerable to these specifically includes initiatives related to agroforestry. predicted changes in climate. Changes in precipitation may In this chapter, we first provide an overview of the history of have the greatest impact, because most of the country’s agricul- agroforestry in Mexico, focusing on the most prominent agro- tural land (about 85 percent) is classified as arid or semiarid forestry systems and their associated tree and crop species, (Houghton et al. 2001). Increases in temperatures and soil moisture management practices, geographic range, and environmental deficits will likely decrease land area suitable for rain-fed crops and climatic conditions. When available, we also provide infor- such as maize. Severe droughts will compound the situation in mation about the agroforestry systems’ potential for enhancing a country where, on average, more than 90 percent of agricul- climate change mitigation (through carbon sequestration and tural losses are already attributed to drought events (Appendini storage) and adaptation to climate change (through improving and Liverman 1994). More intense tropical storms in the food security and resilience). Next, we discuss the existing southern and coastal parts of the country are likely to cause Government policies aimed at promoting different agroforestry extensive damage to crop and livestock production. It is also practices and how these relate to important long-term goals anticipated that changing weather and climate will increase the related to climate change mitigation or adaptation. Finally, we scale and frequency of forest fires, which may contribute to a describe some major constraints to the adoption of agroforestry shift from tropical forests to savannas (MENR 2007). Reducing systems and also the needs and emerging opportunities for agricultural vulnerability to climatic variability is of critical agroforestry in Mexico. importance in the agricultural sector in Mexico, especially given the role the sector plays in support of food security and livelihoods of rural populations. Agroforestry: Enhancing Resiliency in U.S. Agricultural Landscapes Under Changing Conditions 113 Overview of Agroforestry in Mexico The seven most common agroforestry systems in Mexico in recent times are (1) homegardens, (2) improved fallows, (3) Mexico has an area of 1.97 million square kilometers (761,200 living fences, (4) shade trees for agricultural plantations (e.g., square miles) and is one of the 14 most biodiverse countries coffee, cacao, fruit trees), (5) alley cropping (both with crops in the world (Mittermeier et al. 1998). Together with its large, and fodder/pasture), (6) windbreaks, and (7) silvopastoral diverse mosaic of climatic zones, terrestrial ecosystems, and systems (Bautista 2009, Budowski 1987, CONAFOR 2014, plant and animal species, Mexico has immense cultural diversity Dominguez Alvarez and Sanchez Velez 1989, Garcia 2010, that has contributed a wide range of different domesticated crops Gutierrez Ramirez 2006, Musalem-Santiago 2002, Santoyo (e.g., corn, bean, cocoa, vanilla, pineapple, avocado, amaranth, 2004, Wilken 1976). chia) and also land-use systems that include agroforestry (Toledo et al. 2001, 2003). Agroforestry practices were known to have It is notable that agroforestry systems in Mexico have been been implemented during pre-Hispanic times, based on evi- intimately linked with indigenous natural resource management dence of production systems that combined crops and multipur- practices, including the rapid adoption and integration of new pose trees (Barrera et al. 1977). According to Moreno-Calles crops (e.g., coffee) into existing indigenous agroforestry prac- et al. (2014), the most well-documented examples include the tices having high levels of biodiversity (Beaucage 1997). Based chinampas (e.g., floating gardens with trees and crops) that on biocultural diversity, Moreno Calles et al. (2013) identified the Aztecs used in central Mexico and the homegardens (e.g., three main types of agroforestry systems in Mexico: (1) those complex combinations of crops, livestock, and multipurpose associated with spaces near houses, (2) those associated with trees established adjacent to the home) that the Mayans used plots, and (3) those associated with forests and mountains; each in the Yucatan. Agroforestry systems are especially typical of has different levels of management intensity. These agroforestry the extensive tropical habitats, where they are characterized systems commonly found in Mexico contribute to 15 different by complex, spatially and temporally stratified combinations primary uses, most importantly, food (especially fruits), forages of trees, crops, and animals. Combined with other production and medicines, ornamentals, construction materials, energy, strategies, such as roza-tumba-quema (slash-and-burn), these alcoholic beverages, fibers, resins, and latex. systems were implemented extensively in pre-Hispanic times. Also relevant for considering the role of agroforestry in land During the long history of agroforestry in Mexico, the most use and climate change mitigation is the land tenure system, important objective has been the production of subsistence food which is unique to Mexico and differs from most other countries crops and other immediate necessities, such as fiber, medicine, in Central and South America. A major land tenure reform and fuel wood, and only more recently have other products of favorable to common property management arose from the commercial value been included to a great extent (Moreno- Calles Mexican Revolution (1910–1920) (Bray et al. 2005), enabling et al. 2014). Although most agroforestry systems have not con- the communal lands or ejidos to be established. For these reforms, tributed significantly to country-level agricultural production the State effectively gave collective land entitlements to thou- and commercialization based on volume or land cover, they sands of rural communities, resulting in more than 60 percent have been vital to sustaining rural farmers and to retaining the of Mexico’s forested land currently being under communal cultural and biological diversity of Mexico. ownership (Bray et al. 2003, FAO 2010). The internal organi- zation of an ejido allows for collective activities in communal Some of these agroforestry systems have been modified or lands and family-level management in individual parcels. In expanded more recently in response to the introduction of total, some 60 percent of the country’s forest resources are foreign crops like coffee, the internationalization of markets, within communal lands where traditional agroforestry practices technological advances, and changing policy and economic have been documented in at least 25 distinct indigenous groups environments, especially for valuable products such as coffee, scattered throughout the country, but mainly in the center cocoa, and vanilla. and south (Boege 2009, Moreno-Calles et al. 2014). Notably, Despite their long historical importance, agroforestry systems agroforestry systems in Mexico are primarily maintained at in Mexico first gained broad recognition and relevance in 1991, the individual-family scale. The new Agrarian Law of 1992 when a collaborative agreement was signed by the International involved several changes in land tenure in Mexico and its Center for Research in Agroforestry and the Institute of Forest, Federal support. The most significant change was the possi- Agriculture, and Animal Husbandry Research in Mexico. This bility to obtain freehold rights of the parcels, including their collaboration lasted about 10 years and resulted in several privatization (Agrarian