Milpa System Research Articles

Sustainability of agroecological interventions in small scale farming systems in the Western Highlands of Guatemala

ABSTRACT The Western Highlands of Guatemala are dominated by small-scale farming in indigenous communities. Mountain conditions and overpopulation have led to expansion of the agricultural frontier with consequent degradation, decreasing yields, poverty and malnutrition. Several non-government organizations (NGO) have carried out interventions to rescue the milpa system and diversify farming systems. We used the Framework for the Evaluation of Management Systems using Indicators (MESMIS) to evaluate farm sustainability after such interventions. We analysed data from four participating NGOs, interviewing 50 farmers with several years of collaboration as alternative systems, and 50 farmers of recent incorporation as reference systems. A trend towards moderate improvements was found in yields, food availability and reduced losses due to pests, diseases and climatic events. Given the environmental conditions and farm size it seems unlikely that most farms could achieve food self-sufficiency. In some cases, the increase in yields and food security correlate with a higher external input dependence. Even with agroecological interventions, external inputs might be needed. Direct indicators need to be measured in future studies for soil quality and erosion control. Even though the study cases showed regional differences, it was possible to develop a common, robust group of indicators, along with some case-specific ones.

What do we talk about when we talk about milpa? A conceptual approach to the significance, topics of research and impact of the mayan milpa system

The Maya milpa is an ancient agrarian system extended along Mesoamerica, widely known for the slash and burn practices and the polyculture of maize, beans and squashes. Although the Maya milpa has more than three centuries of history, there are several challenges that must be tackled in order to promote the preservation of the system. The aim of this paper is to settle a new starting point in Maya milpa research through a synthesis around the analysis Maya milpa concept, its main lines of research, and its environmental, social, and economic effects in the Yucatan Peninsula. Our research methodology consisted of two different phases: a) the review and analysis of secondary information (169 documents) by means of automated-curation of information (text mining methods) and manual inspection, and b) the design, application, and analysis of 12 interviews using Yucatan Maya milpa researchers as informants. Based on the results we propose some basic elements to consider for an integrative definition of the Maya milpa, we highlight the information gaps described by researchers and checked by wordclouds, and we reveal the most positive and negative impacts of the Maya milpa in terms of environmental, socio-cultural, and economic aspects.

Redes de innovación en sistemas de producción de milpa

Innovation is a process that is not only developed in educational and research institutions. In rural territories, agricultural producers are constantly innovating through the use of tacit or explicit knowledge. This knowledge comes from a variety of information sources, so producers interact with different actors. The aim of this paper is to analyze the relationship between the social interaction, innovation and yields obtained by milpa system producers in six municipalities of the Yucatán Peninsula, in order to propose alternative innovation management strategies that generate individual and collective well-being in the territories. In total, 149 direct interviews were conducted with milpa system producers and then analyzed using the Social Network Analysis methodological tool. Results indicate different network structures in the municipalities depending on their level of innovation, information exchange processes and productive parameters. The factors to be developed in these types of networks refer to increases in the density of their relationships, the diversity of information sources and the quality of the links expressed in improving their productivity.

Diversidad agrícola y seguridad alimentaria nutricional en dos localidades Mayas de Yucatán

Estudios recientes evidencian que la salud, la alimentación y el bienestar de los seres humanos se relacionan directamente con la diversidad de los sistemas agrícolas utilizados para garantizar la seguridad alimentaria nutricional (SAN). Las familias mayas de la Península de Yucatán practican una estrategia de uso múltiple de los recursos agrícolas para fines de subsistencia e intercambio, esto a pesar del monocultivo que ha impulsado la modernidad. El objetivo del presente estudio fue identificar y evaluar la relación que se establece entre la SAN de las familias y la diversidad agrícola de sus sistemas tradicionales de producción milpa y traspatio. Los resultados evidenciaron que no existe una relación significativa (p > 0.05) entre la SAN, los índices de diversidad y las variables económicas, aunque se observó una influencia positiva hacia la citada condición. El sistema traspatio resultó más diverso que la milpa, pero estos recursos son estacionales.

Pluriactividad, consumo y persistencia del maíz en dos municipios del noroeste del Estado de México.

This paper’s main objective is to describe and analyze the socioeconomic and cultural importance of maize production. Based on information obtained through interviews, questionnaires and ethnographic field work, we seek to inquire how maize, and more specifically the milpa system, has persisted despite the negative impacts of neoliberal economic policies on small farmers in two municipalities in the northwest of the State of Mexico: Atlacomulco and San Felipe del Progreso. One of our findings is that, even though agricultural activities have undergone a sustained crisis, they continue to be carried out because they are rooted and are part of people’s identity, responding to long-lasting sociocultural factors, such as the consumption of maize in a large variety of forms, as well as the consumption of other products associated with the milpa system. We contend that this persistence is possible in economic terms because of the presence of non-agricultural activities. In this way, pluriactivity, economic reconversion and different forms of mobility have become the main sources of income that allow families to survive and that lead to the persistence of maize production

Evaluación de la sustentabilidad del sistema milpa en el estado de Tlaxcala, México

El objetivo del estudio es efectuar una evaluación comparativa de la sustentabilidad de dos sistema de producción: a) sistema milpa tradicional y b) sistema de maíz en monocultivo. Para conocer las fortalezas y las debilidades se calculó el tamaño de la muestra (n=380) a partir de la población de productores de maíz, N=29 828. La metodología fue construida desde una perspectiva agroecológica: se aplicó el Marco para la Evaluación de Sistemas de Manejo de Recursos Naturales incorporando indicadores de sustentabilidad y se consideró la escala temporal transversal en el ciclo primavera-verano 2014 en el estado de Tlaxcala, México. Se establecieron 15 indicadores, en los que se abarcaron las dimensiones social, económica y ambiental. Los resultados muestran que solo en un indicador económico, el sistema monocultivo obtuvo el valor más alto; en dos indicadores los valores son similares (balance oferta/demanda de grano y zacate e impacto de políticas agrícolas); en el resto, los resultados favorecieron al sistema milpa. En tres de estos, la diferencia es mayor a 35 puntos porcentuales: relación beneficio/costo, eficiencia en uso de energía fósil y agrodiversidad. Se concluye que en el sistema milpa es favorable la asociación de cultivos, se aprovecha de mejor manera el espacio y los energéticos fósiles empleados y se produce mayor diversidad de alimento humano. Sin embargo, hace falta integrar otros cultivos y prácticas que hagan más sustentables ambos sistemas de producción.

Seasonal Changes in a Maize-Based Polyculture of Central Mexico Reshape the Co-occurrence Networks of Soil Bacterial Communities.

The milpa is a traditional maize-based polyculture in Mexico that is typically practiced as rainfed agriculture. Because milpa cultivation has been practiced over a vast range of environmental and cultural conditions, this agroecosystem is recognized as an important repository of biological and cultural diversity. As for any agroecosystem, the relationship between plant development and the biogeochemical processes of the soil is critical. Although the milpa has been studied from different perspectives, the diversity and structure of microbial communities within milpa soils remain largely unexplored. In this study, we surveyed a milpa system in Central Mexico across cropping season: before planting (dry season; t1), during the early growth of plants (onset of the rainy season; t2), and before harvest (end of the rainy season; t3). In order to examine changes in community structure through time, we characterized bacterial diversity through high-throughput sequencing of 16S rRNA gene amplicons and recorded the nutrient status of multiple (5–10) soil samples from our milpa plots. We estimated microbial diversity from a total of 90 samples and constructed co-occurrence networks. Although we did not find significant changes in diversity or composition of bacterial communities across time, we identified significant rearrangements in their co-occurrence network structure. We found particularly drastic changes between the first and second time points. Co-occurrence analyses showed that the bacterial community changed from a less structured network at (t1) into modules with a non-random composition of taxonomic groups at (t2). We conclude that changes in bacterial communities undetected by standard diversity analyses can become evident when performing co-occurrence network analyses. We also postulate possible functional associations among keystone groups suggested by biogeochemical processes. This study represents the first contribution on soil microbial diversity of a maize-based polyculture and shows its dynamic nature in short-term scales.

Combustibles fósiles y CO2e en sistemas de milpa tradicional y maíz en monocultivo en Tlaxcala, México


 
 
 Se realizó un estudio comparativo entre dos sistemas de manejo en la producción de maíz en Tlaxcala: sistema milpa tradicional (SMT) versus el sistema de maíz en monocultivo (SMo). El objetivo fue conocer la cantidad de energía de origen fósil que se emplea durante el proceso de producción y la emisión de dióxido de carbono equivalente (CO2e). Se estimó la eficiencia de cada sistema y la emisión del principal gas de efecto invernadero (GEI). Para generar información primaria se aplicó una metodología mixta: se realizó entrevista semiestructurada con 20 productores y se calculó un tamaño de muestra para la aplicación de encuesta a partir de datos del programa Proagro Productivo 2014, donde N= 29 828 y n= 379. Después de la colecta de información, se elaboró una base de datos en Excel, se codificó y procesó con el programa SPSS-16. Los resultados evidencian que el mayor gasto de energéticos fósiles en ambos grupos se da en la cosecha y es menor en labores culturales. Sin embargo, en este rubro el gasto de energía derivada de petróleo es dos veces mayor en el SMo. Además, el gasto de energéticos calculado y la emisión de CO2e son 30.8% mayor en el SMo versus el SMT para la misma proporción de maíz producido en cada sistema. Se concluyó que a pesar de que el SMT requiere mayor cantidad de mano de obra y fuerza de tracción animal, es más eficiente en el uso de energéticos de origen fósil y las emisiones de GEI calculados son menores.
 
 

The Milpa system of western Mesoamerica: historical depth, evolutionary dynamics and dispersal routes to South Americao

El nucleo del sistema alimentario preceramico en el occidente de Mesoamerica se pudo integrar con las poblaciones silvestres ancestrales del maiz, el frijol y la calabaza. El manejo agricola incipiente de estas especies, ano tras ano, en un mismo sitio pudo derivar en la estructuracion del sistema agroalimentario conocido como “milpa”. En este trabajo intentamos responder: 1. ?Como y cuando se pudo integrar el sistema agroalimentario de milpa?; 2. ?Que grupos culturales humanos lo pudieron conformar?; 3. ?Pudo ser posible la domesticacion de las poblaciones silvestres del maiz, las calabazas y los frijoles en varios sitios de America?, 4. ?A traves de que rutas y cuando se pudieron difundir estos cultivos? Integramos evidencias paleo-ecologicas arqueologicas, etnobotanicas y genetico-moleculares; analizamos el significado de la domesticacion y la importancia de estudiar la dinamica evolutiva de los complejos poblacionales silvestre-domesticado de las especies cultivadas en la milpa y puntualizamos los retos, amenazas y oportunidades para sus recursos geneticos. El nucleo del sistema agroalimentario Milpa se estructuro con especies de la selva baja caducifolia hace cerca de 9,000 anos. El maiz pudo arribar a Panama, Ecuador y Peru hace 7,400-6,500 anos. Las poblaciones silvestres ancestrales de las calabazas y los frijoles pudieron ser domesticadas tanto en Mesoamerica como en Suramerica. Para las plantas, la domesticacion significo su dependencia de los humanos, y para los humanos un alto costo social no valorado actualmente. El estudio de la dinamica evolutiva de los complejos poblacionales de la milpa nos ayuda a desarrollar estrategias de conservacion y restauracion, y a establecer los riesgos de escape de genes domesticos y transgenes. Los recursos fitogeneticos de la milpa enfrentan grandes amenazas a raiz de los cambios sociales y economicos

Assessment of the potential enhancement of rural food security in Mexico using decision tree land use classification on medium resolution satellite imagery

Because of its renewed importance in international agendas, food security in sub-tropical countries has been the object of studies at different scales, although the spatial components of food security are still largely undocumented. Among other aspects, food security can be assessed using a food selfsufficiency index. We propose a spatial representation of this assessment in the densely populated rural area of the Huasteca Poblana, Mexico, where there is a known tendency towards the loss of selfsufficiency of basic grains. The main agricultural systems in this area are the traditional milpa (a multicrop practice with maize as the main basic crop) system, coffee plantations and grazing land for bovine livestock. We estimate a potential additional milpa - based maize production by smallholders identifying the presence of extensive coffee and pasture systems in the production data of the agricultural census. The surface of extensive coffee plantations and pasture land were estimated using the detailed coffee agricultural census data, and a decision tree combining unsupervised and supervised spectral classification techniques of medium scale (Landsat) satellite imagery. We find that 30% of the territory would benefit more than 50% increment in food security and 13% could theoretically become maize self-sufficient from the conversion of extensive systems to the traditional multicrop milpa system.

Manejo y aprovechamiento de la agrobiodiversidad en el sistema milpa del sureste de México

<p>En este trabajo, se describió y clasificó la agrobiodiversidad del sistema milpa en la región tropical de San Felipe Usila, Oaxaca, México, a partir de la percepción de agricultores sobre la diversidad fenotípica y usos de la variabilidad intraespecífica y biodiversidad recolectada a nivel de parcela. Bajo un enfoque de agroecosistemas, se obtuvo información de tres sistemas de producción, denominados: laderas pedregosas (> 18° de pendiente), lomeríos irregulares y pedregosos con pendientes entre 6 y 18°, y terrenos planos (< 6°) de zonas ribereñas. Así, con el objetivo de registrar la percepción de diversidad y usos de la agrobiodiversidad, se aplicaron entrevistas a 200 agricultores de once comunidades indígenas Chinantecas de San Felipe Usila, mediante un cuestionario semiestructurado. En el análisis de ji-cuadrada, se determinaron relaciones significativas (P < 0.05) entre agroecosistemas y variantes fenotípicas de frijol y maíz, cultivos intercalados, regímenes de humedad para la siembra, superficie sembrada y fechas de siembra, de floración y cosecha de maíz. En el análisis de correspondencia múltiple, se distinguen patrones de diversidad, uso y manejo en relación a regiones geográfico-culturales de localización de los agroecosistemas y parcelas. En las parcelas de producción se siembran, cultivan y recolectan hasta 26 especies, las principales son: maíz (cinco variantes fenotípicas), frijol (21 variedades y poblaciones nativas), calabaza (cuatro variantes) y yuca (tres variantes). También fue notorio el alto uso de pesticidas y fertilizantes químicos, hasta 22 productos diferentes.</p>

Maize–Velvet Bean Rotation in Summer and Winter Milpas: A Greener Technology

In Central America, the traditional cropping system milpa de año (summer season) and tornamilpa (winter season) were compared over 3 yr (2007–2009). Our experimental objectives were to measure the performance of a maize (Zea mays L.)–velvet bean [Mucuna pruriens (L.) DC. subsp. utilis (Wight) Burck] milpa system throughout the summer and winter cultivation, to detect any problems associated with velvet bean use, and to determine the contribution of this tropical legume to soil fertility and maize productivity. In each crop season (separated in space and time) we used a completely randomized design with a 2 × 2 factorial arrangement of treatments with five repetitions each: without velvet bean and without fertilizer (–V–F), with velvet bean and without fertilizer (+V–F), without velvet bean and with fertilizer (–V+F), and with velvet bean and with fertilizer (+V+F). Results showed that in the winter milpas the presence of velvet bean significantly increased the soil pH, organic matter content, total N, and decreased soil bulk density. In both cycles (winter and summer), treatment with velvet bean (+V) produced higher grain yield, while the treatment without velvet bean (–V) had a lower production. We concluded that the use of velvet bean in the winter milpa contributed to the restoration of soil fertility and increased yield maize in agricultural systems of the small‐holder farmers based on low external input.

The Archaic Diet in Mesoamerica: Incentive for Milpa Development and Species Domestication

The Archaic Diet in Mesoamerica: Incentive for Milpa Development and Species Domestication. One of the central questions in the development of Mesoamerican civilization is how the alimentary, agronomic, and ecological complementarities were achieved within the milpa agroecosystem, which is one of its more important and distinctive cultural elements. In the Mesoamerican center of origin of agriculture and domestication of plants, located in western Mexico, we inquired among Nahuatl communities about the ancient dishes prepared with wild plants that are part of their ancient foodways, and the tools and technology used to prepare them. We found that the wild progenitors of Agave spp., Zea mays L, Cucurbita argyrosperma Hort. Ex L.H. Bayley, Phaseolus spp., Capsicum annum L., Solanum lycopersicum L., Physalis phyladelphica Lam, Spondias purpurea L., Persea americana Mill., and Hyptis suaveolens (L.) Poit are consumed in dishes that remain in the present food culture of the poor peasants, and are prepared with techniques and tools that were available in the Archaic period: Sun drying, roasting, toasting, baking, cracking, grinding, crushing, fermenting, and soaking in plain water or in water with ash, using three–stone fireplaces, stone toasters, crushers, grinders, rock pits, and three types of earth ovens. A remarkable finding was that beans could be incorporated into the diet without boiling, but just by toasting, stone grinding, and baking in corn dough tamales. Results obtained suggest that the basic Mesoamerican diet could have been shaped before the species involved were domesticated. Its nutritional complementarity since the Archaic period could have been one of the incentives for the development of the milpa system and the domestication of its species, achieving in this way also their ecological and agronomical complementarity.

Evolution and Domestication of Lima Bean in Mexico: Evidence from Ribosomal DNA

ABSTRACTPhaseolus lunatus L., Lima bean, has been domesticated at least twice in the Americas, once in the Andean region and at another time in Mesoamerica; however, the domestication history of this crop in the latter region remains unclear. In this study, a phylogeographic analysis of DNA polymorphisms in the internal transcribed spacer (ITS) region of the ribosomal DNA from a collection of wild and domesticated accessions was applied to establish where and how many times in Mesoamerica Lima bean was domesticated. The results showed evidence for two wild Mesoamerican gene pools with contrasting geographical distributions. While the MI gene pool occurs in central western Mexico, including the Pacific coastal range, the MII gene pool is widespread and occurs toward the Gulf of Mexico, the Yucatan peninsula, and Central and South America. In a cluster analysis, all Mesoamerican landraces clustered together with wild accessions from the MI gene pool (L haplotype) suggesting a unique domestication event in central western Mexico. The most likely domestication region is an area of the states of Nayarit–Jalisco or Guerrero–Oaxaca and not areas such as the Peninsula of Yucatan where the crop is currently widespread and diverse. A strong founder effect due to domestication was quantified and several recently diversified haplotypes were identified. A hypothesis about possible dispersal routes of the crop within Mesoamerica is proposed as well as an apparent late adoption of the crop into the milpa system.

Effects of weed control and manure application on nutrient fluxes in the shifting cultivation milpa system of Yucatán

Maize (Zea mays L.) cultivation under the shifting cultivation system of Yucatán, Mexico, is normally limited to 2–3 years due to nutrient depletion and weed pressure. This study was undertaken to evaluate the effect of manure application and weed control on partial nutrient budgets for maize, and assess the effect of grain-only or whole-plant harvest on nutrient removal. Two farms were selected near Mérida, Mexico, each including two cultivation years. Maize grain, stem, and leaf fractions were harvested and analyzed for N, P, and K concentrations, and compared to quantities added through manure, to generate partial nutrient budgets. Multiple years of cultivation did not change soil organic matter content while extractable P was reduced (53–62%) at both farms and extractable K was lower (22%) for farm 1. Plant fractions contained similar amounts of N, while P accumulated in grain, and stem and leaf contained the largest K pools. Applied treatments affected crop nutrient removal predominantly through crop yield. Partial nutrient budgets suggested that with stover removal, the lower rate of manure may be sufficient to maintain P, but not N or K; whereas with the higher rate of manure all partial budgets were positive, suggesting nutrient accumulation over time.

Complejos raciales de poblaciones de maíz evaluadas en San Martín Huamelulpan, Oaxaca

El sistema milpa genera y mantiene la mayor proporción de la diversidad de maíz en México, y particularmente en la región Mixteca oaxaqueña este proceso ocurre desde la época precolombina. Con el objetivo de evaluar la variación fenotípica del maíz mixteco, se hizo una colecta y caracterización de 100 muestras poblacionales de maíz de 14 municipios del distrito de Tlaxiaco, Oaxaca. Las muestras se sembraron bajo un diseño de látice simple con dos repeticiones en el ciclo verano-otoño 2008. La descripción morfológica se realizó con base en 18 caracteres más el rendimiento de grano. El análisis de varianza detectó diferencias significativas entre colectas para todas las variables, excepto para número de ramas secundarias de la espiga y diámetro del raquis del olote. El análisis de componentes principales mostró que la variación morfológica evaluada presentó un patrón altitudinal de acuerdo con el origen de colecta. La altura de mazorca y planta, longitud y número de ramas de la espiga, días a floración femenina, longitud y número de hileras de la mazorca explicaron la mayor proporción de la variabilidad morfológica. Se determinaron nueve grupos fenotípicos mediante el análisis de conglomerados, denominados como raza Mixteco, raza Chalqueño y siete complejos raciales integrados por expresiones fenotípicas de las razas Chalqueño, Cónico, Mixteco y Pepitilla. Las colectas mostraron una alta variación morfológica y en rendimiento, y se diferenciaron las razas Chalqueño y Mixteco, y siete complejos raciales. Durante la evaluación se observaron poblaciones con características de mazorca semejantes a las descritas para las razas Bolita, Serrano Mixe y Ancho.

Origin of agriculture and plant domestication in West Mesoamerica

Recent paleoecological, archaeobotanical and genetic-molecular data are used to develop a hypothesis on the where, when, how and whom of plant domestication and the origin of agriculture in west Mesoamerica, and the formation of the maize-bean-squash multicrop milpa system and agro-food system which formed the base for development of ancient complex societies in this area. It is highly likely that about 10,000 before present (BP) human groups specializing in plant gathering and small game hunting in the dry tropical forest of the Balsas-Jalisco biotic morphotectonic province began the process of plant domestication and agriculture, using fire as a tool. Sympatric distribution of the putative wild ancestral populations of maize, beans and squash indicate the extreme northwest Balsas-Jalisco region as a possible locus of domestication. Diffusion of these domesticates to the rest of Mesoamerica would have occurred via existing biological-cultural corridors. The milpa agro-food system would have been established between 7,000 and 4,400 calendar years (cal) BP. The complex food technology developed in the northwest Balsas-Jalisco region between 4,500 and 3,500 BP, much more complex than in other areas at the time, also suggests this area as the origin of the milpa agro-food system. Further archaeobotanical research is needed to confirm this hypothesis. Exploratory, collection and conservation efforts are needed in these putative source populations, as well as studies on their adaptation to climatic, edaphic and biotic factors, before they are displaced by the African grasses and pesticides forming part of the region’s growing cattle industry.

Genetic diversity and agricultural strategy in 16th century and present-day Yucatecan milpa agriculture

This article is an attempt to understand pre-Columbia Maya milpa agriculture by comparing historical reports with today's practices. It is also an attempt to evaluate the potential of present-day milpa agriculture by comparing it with pre-Columbian production. Structurally, today's milpa system is very similar to the pre-Columbian. Both are characterized by a high diversity of genetic resources and many agricultural and non-agricultural activities. However, in pre-Columbian times all land was dedicated to milpa farming, land was communal, settlement was dispersed, and the system was supported by the ruling class. All together this resulted in a higher productivity than today, where these conditions are absent.

The Persistence of Milpa Agriculture in Highland Guatemala1

In southwestern Guatemala, within the western realms of the basin of Quezaltenango, peasants have maintained the traditional system of milpa agriculture in the face of repeated cultural intrusions. The Spanish conquest resulted in the adoption of a plethora of tools, crops and domesticated animals that modified, but did not alter the basic character of the milpa. The milpa system has evolved more recently to accommodate the production of cash crops, principally wheat and potatoes. Chemical fertilizers, herbicides, pesticides and improved varieties of seed have been accepted as necessary adjuncts in the production of these crops. In contradiction of the counsel of well-intentioned advisors, however, the Guatemalan peasants persist in their adherence to the traditional milpa. Many Westerners are inclined to regard this as irrational behavior. Although not capable of articulating fully all of the subtle advantages of milpa agriculture, the majority of the region's peasants perceive the milpa as an economical...

Some Comments on "Manihot" Subsistence and the Ancient Maya

In 1966, Bronson proposed that root crops, especially manioc, played an important subsistence role in Ancient Mayan civilization and that they provide better subsistence for a substantial population than does maize. The present paper, although limited in scope to the Peten, casts doubt upon Bronson's hypotheses. Edaphic factors in the Peten are such that manioc can flourish in only a limited number of locations. Maize is nutritionally a more valuable staple than manioc. Under the present milpa system of agriculture, one milpero can feed 12.6 people annually with maize. Calculations based upon the same system indicate that a milpero could feed 16 people annually with manioc tuber and 7.75 with manioc flour. Root crops are also more vulnerable to disease and attack by animals than is maize. Paleoecological data, though inconclusive, suggest that root crops may not have been important among the Ancient Maya.