Raised Fields

This article examines the productivity of agriculture at the Postclassic polity of Xaltocan, Mexico. Employing multiple lines of data (remote sensing, artifactual, ecofactual, chronological, demographic, historic, ethnographic, and environmental), it reconstructs the potential productivity of an integrated raised field, chinampa system that surrounded the polity. This exercise reveals that the system was capable of producing a sizeable caloric surplus above the needs of the kingdom's estimated total population and the number of laborers necessary to maintain full production. To situate the processes related to agricultural production, the paper considers how farmers' strategies were articulated with multiple institutions. Increased integration between political, social, and household institutions possibly fostered residents' incorporation into the body politic and provided mechanisms to finance the political economy. Such integration and dependency fractured, however, when Xaltocan was conquered.

This dissertation presents the first large, detailed spatial reconstruction of Aztec lakebed chinampas for a 1,010 hectare area of the former Lake Xochimilco lakebed. A general five stage model is proposed for the development and decline of the raised field socio-natural system in the southern Basin of Mexico. Widespread chinampas in the 18,000 ha Lake Chalco-Xochimilco were restricted to the relatively short-lived Aztec empire period especially between the mid-15th and early 16th centuries and were the result of top-down imperial planning, construction oversight, and hydraulic and facility management. Previous archaeological survey in 1969 and 1972 overwhelmingly dated lakebed occupation to the Late Aztec and Early Colonial periods (Aztec III-IV ceramics). The rapid inundation of Aztec drained fields after the Spanish conquest submerged most lakebed chinampas below the marshy southern lake surface. The relic fields were exposed for a short period in the 20th century after lake drainage completion and before post-WWII mechanized farming and urbanization obliterated the relic fields. By incorporating 1936-1941 air photos into a GIS, 23,094 relic beds and 400 mounds were manually digitized (traced) for the 1,010 ha study area. The built beds and mounds in the lake also defined complex canal networks and open pools within the system. The long, narrow beds averaged 3.75 meters wide and had an average length of 49.4 meters. The system land to water ratio was 1.07:1. Raised field experiments on the Andean high plain of Lake Titicaca and elsewhere demonstrate that narrow agricultural beds in 1:1 land to water systems benefit from both frost protection and intra-system nutrient replacement. Additionally, every plant on the narrow beds could have been irrigated by splash or scoop techniques from canoe bound farmers – an important benefit in the Basin of Mexico characterized by a long dry season, variable (temporal and spatial) summer monsoon rains, and summer droughts (canícula). In addition to many small lakebed habitation sites, larger lakebed wharves comprised of multiple mounds and platforms, open pools, and wider
iv
canals were identified in the air photos. These village-wharves probably formed the economic and social hub for the lakebed tenant farmers who were comprised of free peasants (macehualtin), serfs (mayeque), and slaves (tlacotin). Aztec chinampas built through land reclamation existed outside traditional corporate land holding capolli system and tenant farmers obtained rights of cultivation in return for approximately 50% of their agricultural production in rent payment to land grantees residing in Tenochtitlan (Calnek 1975). I estimate that approximately 2,525 farmers, administrators, dockworkers, merchants, and canoeists resided in the 1,010 ha study area (2.5 persons/ha) which included 2,000 full-time tenant farmers. Extrapolating these figures after adjusting for possible larger open pools within a 13,435 ha Chalco-Xochimilco Aztec drained field system, I calculate that after the consumption needs (dietary and non-dietary) of 30,000 lakebed residents were met, an annual 10,000,000 kg maize equivalent agricultural surplus, enough to feed 50,000 persons for a year, reached the storehouses and markets of Tlatelolco-Tenochtitlan. Also, this dissertation describes the temporal changes in agricultural bed width and land to water ratios resulting from a falling water table and canal in-filling accompanying Mexico City’s growth and constant water demand. The land to water ratios increased from 1.07:1 (Aztec) to 2.75:1 in 1941 to 10.11 in 2012. Average bed area in the desiccating system has risen from 221m2 (Aztec) to 2,054m2 in 1941 to 62,799m2 in 2012. Modern chinampas are no longer self-sustaining systems as plastic tarps (invernaderos) provide frost protection, gas-powered pumps deliver reclaimed urban water (transferred to the system) to the plants on the large fields, and external organic and chemical inputs introduce nutrients and contaminants to the soils. The Xochimilco lakebed chinampas, while still highly productive, have transformed from an Aztec period waterscape to a desiccating farmscape with a wetland agriculture ancestry.

This paper uses remote sensing data to document a raised field, chinampa system adjacent to the Postclassic kingdom of Xaltocan in the northern Basin of Mexico. Various forms of landscape information; historic records and maps as well as remote sensing; are considered to understand the chinampa system. The remote sensing data examined include 1950s aerial photographs, Landsat 7 data, and Quickbird VHR, multi-spectral imagery. This article evaluates the utility of each of these forms of data to identify buried chinampa features and integrates them in a GIS to produce a map of Xaltocan's chinampa landscape. Canals of various sizes and hydrological positions comprised the chinampas and integrated the system together. Occupying at least 1500–2000 ha, Xaltocan's chinampa system represents the largest pre-Aztec, chinampa system in the Basin of Mexico.► Evaluation of remote sensing data to identify raised field, chinampa agriculture. ► Integration of remote sensing data in a GIS to map chinampa landscape. ► Discussion of size and structure of largest, pre-Aztec chinampa system.

Urban horticulture is not as new as many people think. Throughout history, different techniques have been used to ensure sustainable urban agricultural production. A good example of this is the chinampa system, which was developed during the time of the Aztecs in the region of Lake Xochimilco, south of Mexico City. A chinampa is a raised field on a small artificial island on a freshwater lake surrounded by canals and ditches. Farmers use local vegetation and mud to construct chinampas. Fences made of a native willow [bonpland willow (Salix bonplandiana)] protect the chinampa from wind, pests, and erosion. The dominating crops are vegetables and ornamentals. The canal water that rises through capillarity to the crops reduces the need for additional irrigation. A considerable portion of the fertility in the soils is system-immanent and generated in the aquatic components of the chinampa. Complex rotations and associations allow up to seven harvests per year. Chinampas also provide ecosystem services, particularly greenhouse gas sequestration and biodiversity diversification, and they offer high recreational potential. Recently, research and community initiatives have been performed to try to recover the productive potential of chinampas and align this sustainable system with the needs of the 21st century. In other parts of the world, some with a history of raised field agriculture, similar efforts are being made. The chinampa model could help supply food and ecosystem services in large cities on or near swamplands, large rivers, or lakes.

The thesis is about the impressive pre-Columbian agricultural system based on raised fields found in the Llanos de Moxos, a seasonally flooded savannah in the Bolivian Amazon. Despite the growing scientific interest and several rehabilitation projects, very little empirical research has been carried out. As a result, not much is known about how these fields were constructed, managed and within which time frame they were in use. The dissertation shows that the local environmental context (soils, hydrology) is crucial for the development and functioning of raised fields. Dating of fields sediments with OSL reveals that raised fields were in use at least between 600 AD and 1400 AD. Finally, the thesis advances a series of arguments suggesting that the fields were not used on a continuous basis and their management required long fallow periods, challenging the idea that raised fields per se were able to support dense populations.

"Vast tracts of prehistoric raised fields are present in the Titicaca Basin of Bolivia and Peru. Archaeologists at present consider raised field agriculture to have been much more productive and efficient than the rain-fed dryland agriculture currently practiced in the region. However, the recent failure of a number of long-term raised field rehabilitation projects has called this understanding into question. In this paper, I review the production, labor requirements, and energetic efficiency of raised field agriculture. Contrary to the existing literature, I conclude that raised field agriculture was always somewhat less efficient than traditional rain-fed dryland agriculture. Finally, I propose a new model of the political economic role of raised field agriculture. In order to appreciate the role played by raised fields in ancient Andean complex polities it is necessary to abandon the unrealistic model of raised field agriculture currently dominant in the archaeological literature."

We present an integrated palaeoecological and archaeobotanical study of pre-Columbian raised-field agriculture in the Llanos de Moxos, a vast seasonally inundated forest-savanna mosaic in the Bolivian Amazon. Phytoliths from excavated raised-field soil units, together with pollen and charcoal in sediment cores from two oxbow lakes, were analysed to provide a history of land use and agriculture at the El Cerro raised-field site. The construction of raised fields involved the removal of savanna trees, and gallery forest was cleared from the area by ad 310. Despite the low fertility of Llanos de Moxos soils, we determined that pre-Columbian raised-field agriculture sufficiently improved soil conditions for maize cultivation. Fire was used as a common management practice until ad 1300, at which point, the land-use strategy shifted towards less frequent burning of savannas and raised fields. Alongside a reduction in the use of fire, sweet potato cultivation and the exploitation of Inga fruits formed part of a mixed resource strategy from ad 1300 to 1450. The pre-Columbian impact on the landscape began to lessen around ad 1450, as shown by an increase in savanna trees and gallery forest. Although agriculture at the site began to decline prior to European arrival, the abandonment of raised fields was protracted, with evidence of sweet potato cultivation occurring as late as ad 1800.

Pre-Columbian inhabitants of the western Llanos de Moxos, Bolivia, transformed large expanses of seasonally flooded savannah into a complex agricultural landscape. Extensive raised field systems, along with associated canals and causeways, suggest a sophisticated approach to managing land and water resources for permanent, intensive, agricultural production. However, the detailed construction history, specific crops, and palaeoenvironmental impacts of these fields are poorly known.  To investigate these issues, we analyzed stratigraphy and phytoliths from two raised fields (camellones) at the site of Campo España, western Beni, Bolivia. Results indicate that prior to field construction, vegetation was mainly palm savannah.  A decline in arboreal phytolith frequencies is associated with human clearing and initial field construction.  A peak in burnt grass phytoliths followed by an increase of Asteraceae, suggests a period of regular field maintenance and intensive agricultural use.  Maize (Zea mays) and possibly manioc (Manihot esculenta) were grown.  A small increase in arboreal phytoliths suggests some forest recovery after field abandonment.  This study demonstrates the utility of phytolith and stratigraphic analyses in reconstructing construction, cultivation, and palaeoenvironmental histories of raised field systems, and assessing their role within the advanced agricultural landscape management practiced by pre-Columbian populations in the Bolivian Amazon.

El cambio climático y su probable influencia en la construcción de obras de infraestructura Ulises Chávez hidráulica temprana, en la cuenca media del río candelaria, campeche [email protected] El cambio climático y su probable influencia en la construcción de obras de infraestructura Ulises Chávez hidráulica temprana, en la cuenca media del río candelaria, campeche [email protected] temporal capaz de respaldar y complementar la información proveniente de las secuencias cerámicas de por lo menos un gran sitio arqueológico en el área: El Tigre; ocupado desde al menos el Preclásico Medio (800 a.C.) y que de acuerdo con algunos autores, ha sido identificado con la Itzamkanac de las fuentes históricas, la capital Yokot´an ´ob de la provincia de Acalán, descrita por Bernal Díaz y Hernán Cortés a mediados del siglo XVI. Por lo que en conjunto y en teoría, al efectuarse los estudios pertinentes los campos levantados podrían potencialmente arrojar una temporalidad sobre su uso de más de 2,000 años.

Archaeologists have long associated the development of agriculture with the rise of the state. But the archaeology of the Amazon Basin, revealing traces of agriculture but lacking evidence of statehood, confounds their assumptions. John H. Walker’s innovative study of the Bolivian Amazon addresses this contradiction by examining the agricultural landscape and analyzing the earthworks from an archaeological perspective. The archaeological data is presented in ascending scale throughout the book. Scholars across archaeology and environmental anthropology will find the methodology and theoretical arguments essential for further study.

In 1979, when I was working with the Cuello Project, Bill and Peter were conducting the first phase of their Pulltrouser Swamp investigations. They were often in the Cuello Camp and seemed fascinated with the flotation samples I was processing. At the end of the season, they sent me material form the 1979 excavations for analysis. They then invited me on their 1981 more intensive project. Bill headed up the Pulltrouser 1 volume which this report is in. I finished a manuscript for Volume 2 in 1984 and sent it off to Bill, Peter, and several of the other project members who were writing up various parts of the research. Peter was supposed to pull together Volume 2, but unfortunately that never happened. The 1984 manuscript is available at https://www.academia.edu/9179721/Paleoecology_and_Subsistence_at_Pulltrouser_Swamp_The_View_from_the_Float_Tank . It is farm more complete than the "Preliminary Report" in Volume 1.

I am not quite sure why I haven't posted this before.

Citation: In Pulltrouser Swamp: Ancient Maya Habitat, Agriculture, and Settlement in Northern Belize. edited by B. L. Turner II and Peter D. Harrison. pp 94 - 104. University of Texas Press, Austin.

Los camellones garantizan el acceso continuo a alimentos en el altiplano, ecosistema frecuentemente expuesto a eventos meteorológicos extremos. Se explora la relación entre el abandono del cultivo en camellones y el énfasis dado por el Gobierno distrital de Huata a la promoción ganadera. En relación con las políticas vacunocéntricas, comprendidas en la denominada “vía láctea”, se cuestiona de qué manera garantizan la
seguridad alimentaria de la población, teniendo en cuenta que Puno es el departamento más vulnerable a la inseguridad alimentaria a nivel nacional. El análisis aborda la relación entre el abandono de los camellones y las políticas vacunocéntricas a partir de las actividades económicas realizadas por el habitante del campo. Se muestra que, si bien la vía láctea permite ingresos inmediatos, el abandono de los camellones debilita la
continuidad y diversidad alimentaria a corto y largo
plazo.

The use of raised beds (i.e., ridged soil layers) to cultivate vegetables can improve soil quality, crop performance, water use and even reduce soil erosion. Although those advantages are well known and documented in the literature for many vegetable species, Radicchio, a particular variety of chicory, is usually cultivated in flat seed-beds and, therefore, the achievable benefits of raised beds for this vegetable are not yet known. The possibility to grow plants of Radicchio on raised beds is here evaluated by comparing the most important yield performances indicators deriving from the adoption of this practice (grown plants percentage, average head weight, marketable yields, and net incomes) with the same indicators recorded with a conventional practice making use of flat seed-beds. The results evidenced that raised beds for Radicchio had a statistically significant effect on the average head weight (+55.45 g plant-1 with 15-cm beds) with significant increases of field yields (up to +30.6%) and net incomes (up to +29.7%) on the trials with flat seed-beds. The experiment showed that the production of chicory can take an economical advantage from the use of raised seed-beds and, therefore, this system is preferable to the traditional cultivation practice.

A previously unpublished report on the plant remains from the 1981 NSF Sponsored Pulltrouser Swamp Project. This manuscript was circulated with Bill Turner, Peter Harrison, and several members of the team who were writing up various aspects of the Project. Unfortunately Pulltrouser II never came out. Pulltrouser I, the results of the 1979 field season came out in 1983.

En la costa pacífica del sur de Colombia y norte del Ecuador el paisaje fue ampliamente modificado por las sociedades prehispánicas en los últimos tres mil años. Las cuales construyeron canales, zanjas, camellones y plataformas para actividades agrícolas y posiblemente domésticas. Estas estructuras, que abarcan más de cuatro mil hectáreas, nunca habían sido estudiadas exhaustivamente en esta región del continente, por lo cual nuestras preguntas iniciales tratan sobre su función, su proceso de construcción, y la razón de su abandono.
Para intentar responderlas se utilizaron métodos de cartografía (Sistemas de información geográfica) y fotogrametría cuyo desenlace llevó a la creación del primer mapa de distribución de estas estructuras. Las cuales se relacionaron con las diferentes zonas ecológicas, los aspectos geomorfológicos de la región, y con los sitios de habitación de cada periodo de ocupación.
Los resultados permiten comprender mejor cómo funcionaban esas estructuras, además de indicarnos cuál fue su posible época de construcción y de abandono. Así mismo se dieron nuevos elementos para abrir el debate sobre la organización social de las comunidades que construyeron esas estructuras y las posibles estrategias de adaptación a cambios climáticos graduales o repentinos.

Pre-Columbian inhabitants of the western Llanos de Moxos, Bolivia, transformed large expanses of seasonally flooded savannah into a complex agricultural landscape. Extensive raised field systems, along with associated canals and causeways, suggest a sophisticated approach to managing land and water resources for permanent, intensive, agricultural production. However, the detailed construction history, specific crops, and palaeoenvironmental impacts of these fields are poorly known. To investigate these issues, we analyzed stratigraphy and phytoliths from two raised fields (camellones) at the site of Campo España, western Beni, Bolivia. Results indicate that prior to field construction, vegetation was mainly palm savannah. A decline in arboreal phytolith frequencies is associated with human clearing and initial field construction. A peak in burnt grass phytoliths followed by an increase of Asteraceae, suggests a period of regular field maintenance and intensive agricultural use. Maiz...

Pre-Columbian raised field agriculture in the tropical lowlands of South America has received increasing attention and been the focus of heated debates regarding its function, productivity, and role in the development of pre-Columbian societies. Even though raised fields are all associated to permanent or semi-permanent high water levels, they occur in different environmental contexts. Very few field-based studies on raised fields have been carried out in the tropical lowlands and little is known about their use and past management. Based on topographic surveying and mapping, soil physical/chemical analysis and OSL and radiocarbon dating, this paper provides insight into the morphology, functioning and time frame of the use of raised fields in the south-western Llanos de Moxos, Bolivian Amazon. We have studied raised fields of different sizes that were built in an area, near the town of San Borja, with a complex fluvial history. The results show that differences in field size and he...

Pre-Columbian raised field agriculture in the tropical lowlands of South America has received increasing attention and been the focus of heated debates regarding its function, productivity, and role in the development of pre-Columbian societies. Even though raised fields are all associated to permanent or semi-permanent high water levels, they occur in different 10 environmental contexts. Very few field-based studies on raised fields have been carried out in the tropical lowlands and little is known about their use and past management. Based on topographic surveying and mapping, soil physical/chemical analysis and OSL and radiocarbon dating, this paper provides insight into the morphology, functioning and time frame of the use of raised fields in the southwestern Llanos de Moxos, Bolivian Amazon. We have studied raised fields of different sizes that were built in an area, near the town of San Borja, with a complex fluvial history. The results show that differences in field size 15 and height are the result of an adaptation to a site where soil properties vary significantly on a scale of tens to hundreds of meters. The analysis and dating of the raised fields sediments point towards an extensive and rather brief use of the raised fields, for about 100-200 years at the beginning of the 2nd millennium.

"This dissertation presents the first large, detailed spatial reconstruction of Aztec lakebed chinampas for a 1,010 hectare area of the former Lake Xochimilco lakebed. A general five stage model is proposed for the development and decline of the raised field socio-natural system in the southern Basin of Mexico. Widespread chinampas in the 18,000 ha Lake Chalco-Xochimilco were restricted to the relatively short-lived Aztec empire period especially between the mid-15th and early 16th centuries and were the result of top-down imperial planning, construction oversight, and hydraulic and facility management. Previous archaeological survey in 1969 and 1972 overwhelmingly dated lakebed occupation to the Late Aztec and Early Colonial periods (Aztec III-IV ceramics). The rapid inundation of Aztec drained fields after the Spanish conquest submerged most lakebed chinampas below the marshy southern lake surface. The relic fields were exposed for a short period in the 20th century after lake drainage completion and before post-WWII mechanized farming and urbanization obliterated the relic fields. By incorporating 1936-1941 air photos into a GIS, 23,094 relic beds and 400 mounds were manually digitized (traced) for the 1,010 ha study area. The built beds and mounds in the lake also defined complex canal networks and open pools within the system. The long, narrow beds averaged 3.75 meters wide and had an average length of 49.4 meters. The system land to water ratio was 1.07:1. Raised field experiments on the Andean high plain of Lake Titicaca and elsewhere demonstrate that narrow agricultural beds in 1:1 land to water systems benefit from both frost protection and intra-system nutrient replacement. Additionally, every plant on the narrow beds could have been irrigated by splash or scoop techniques from canoe bound farmers – an important benefit in the Basin of Mexico characterized by a long dry season, variable (temporal and spatial) summer monsoon rains, and summer droughts (canícula). In addition to many small lakebed habitation sites, larger lakebed wharves comprised of multiple mounds and platforms, open pools, and wider iv canals were identified in the air photos. These village-wharves probably formed the economic and social hub for the lakebed tenant farmers who were comprised of free peasants (macehualtin), serfs (mayeque), and slaves (tlacotin). Aztec chinampas built through land reclamation existed outside traditional corporate land holding capolli system and tenant farmers obtained rights of cultivation in return for approximately 50% of their agricultural production in rent payment to land grantees residing in Tenochtitlan (Calnek 1975). I estimate that approximately 2,525 farmers, administrators, dockworkers, merchants, and canoeists resided in the 1,010 ha study area (2.5 persons/ha) which included 2,000 full-time tenant farmers. Extrapolating these figures after adjusting for possible larger open pools within a 13,435 ha Chalco-Xochimilco Aztec drained field system, I calculate that after the consumption needs (dietary and non-dietary) of 30,000 lakebed residents were met, an annual 10,000,000 kg maize equivalent agricultural surplus, enough to feed 50,000 persons for a year, reached the storehouses and markets of Tlatelolco-Tenochtitlan. Also, this dissertation describes the temporal changes in agricultural bed width and land to water ratios resulting from a falling water table and canal in-filling accompanying Mexico City’s growth and constant water demand. The land to water ratios increased from 1.07:1 (Aztec) to 2.75:1 in 1941 to 10.11 in 2012. Average bed area in the desiccating system has risen from 221m2 (Aztec) to 2,054m2 in 1941 to 62,799m2 in 2012. Modern chinampas are no longer self-sustaining systems as plastic tarps (invernaderos) provide frost protection, gas-powered pumps deliver reclaimed urban water (transferred to the system) to the plants on the large fields, and external organic and chemical inputs introduce nutrients and contaminants to the soils. The Xochimilco lakebed chinampas, while still highly productive, have transformed from an Aztec period waterscape to a desiccating farmscape with a wetland agriculture ancestry."