User:Sturls/Raised field

Raised field agriculture (RF) (Spanish: camellones; Quechua: waru waru; Aymara: suka kollus; Kʼicheʼ: chinampa)  is a type of farming practice in which elevated, rectangular plant beds are built up in the shallow waters of a lake, floodplain, or other inland wetland area. These platforms create reliable drainage systems, foster micro-environments for aquaculture and aquaponics, and increase soil fertility. Studies have also shown that the low thermal diffusion value of water protects the crops from extreme temperature fluctuation, which prolongs the growing season in cold climates. The system of elevated soil beds alongside water channels creates an environment that is also resistant to wildfires and flooding. RF is often used in conjunction with other subsistence strategies and agricultural systems such as fishing and traditional farming.

While today RF is a common, yet labor intensive, agricultural practice across the globe, most scholastic attention on RF has focused on the presence of RF in the Pre-Columbian Americas.

Construction
Raised fields are built by excavating channels on either side of the desired plant bed. The displaced soil is then piled in the center of the bed to form a flat or slightly rounded surface. The channels built in RF in seasonal flood plains, the water drains each year. In other areas such as on the sides of lakes the channels remain filled year round.

The internal structure of these raised beds varies widely. For example, the ancient raised fields at Pampa Koanin, located on the south coast of Lake Titicaca in Bolivia, had two varieties. The first field type was composed of homogenous, loamy clay while the second contained a layered sequence of small stones (ballast), clay, sorted gravels, and top soil. RF in the Congo basin relies on grasses and large root systems for structural support and hold the beds together. Farmers rejuvenate the soil in the raised beds by periodically adding the high-nutrient and low- alkalinity adjacent channel sediment to the beds. Sediment analyses have shown that canal sediment typically contains a richer nutrient profile than regular lakeside soil due to its concentration of organic matter.

RF in the Americas comes in all shapes and sizes. Fields are built in round, rectilinear, linear, or curvilinear arrangements. In prehistory, the chinampas on Lake Texcoco were arranged in parallel grids. RF in the ancient Altiplano were constructed variety of parallel folded configurations, like the folds of a mitochondria. These fields were generally 4-10m wide, 10 to 100 m long, and 1 m tall.

RF is often used in conjunction with other agricultural technologies such as canals and aqueducts.

Crop varieties
In the Andean Altiplano potato, quinua, and cañihua are grown using RF. RF crops in the Congo Basin include manoic and other tubers as well as sweet potato, Cuinea sorrel, sugar cane, pineapple, banana, maize, peanuts, okra, pepper, amarath, eggplant, and tomato. In Central America maize is a common crop with some cultivation of cotton and amaranth.

South America
In prehistoric South America, raised field agriculture was one of many farming technologies that turned the high grassland and low floodplain regions into efficient production sources for socially complex communities. Scholars have linked the extensive droughts in the Late Holocene to the collapse Andean agrarian civilizations such as the Moche circa 700 AD and Tiwanaku circa 1100AD. Water, whether in lower elevations’ river valleys or the higher Altiplano’s cold grasslands, was not a plentiful resource (disregarding El Nino years where flooding was common) and had to be managed carefully in accordance with the subsistence needs of the local population. Agricultural practices and technologies were politicized and linked to statecraft. To this end, raised field agriculture was used alongside canals, terraces, aqueducts, and puqiuos to control the flow of water in an area. Examples of RF in prehistory can be found in the Altiplano around Lake Titicaca, tropical savannas in Columbia and Venezuela, highland regions of Ecuador and Peru, and tropical coastal areas in Surinam and French Guiana. In most areas RF was abandoned before or shortly after the Spanish conquest in the early 1500s.

**** INCORPORATE Denevan, W.; Turner, B. Forms, functions and associations of raised ﬁelds in the Old World tropics. J.Trop. Geogr. 1974, 39, 24–33.

Amazonia
In Pre-Columbian times farmers built RF in the seasonally-flooded coastal savannas of the Guianas. Used in conjuction with canals and ponds, RF beds were built in circular mounds of all sizes or elongated parallel ridges. Archaeological excavation has dated the early instances of RF in this region to approximately 825 and 990 14C y B.P. (708–938 Cal y B.P.)

In the Rio San Jorge Valley in Colombia, farmers created an estimated 200,000 ha of RF.

Denevan, W.M. Cultivated Landscapes of Native Amazonia and the Andes; Oxford University Press: Oxford, UK, 2001; 396p, ISBN 978-0-19-925769-0.

McKey, D.; Rostain, S.; Iriarte, J.; Glaser, B.; Birk, J.J.; Holst, I.; Renard, D. Pre-Columbian agricultural landscapes, ecosystem engineers, and self-organized patchiness in Amazonia. Proc. Natl. Acad. Sci. USA 2010, 107, 7823–7828. [CrossRef] [PubMed]

Peru
The Chimu Empire (900-1470AD) in the Casma Valley of Peru is one such culture that created RF as a state project in order to increase its agricultural production. These fields are notable as they are the only examples of raised field agriculture on the arid, dry coast of South America. Scholars postulate that the raised fields were created in response to years of significant flooding.

Bolivia
The seasonally-flooded grassy lowlands of the Llanos de Mojos in Bolivia also hosted extensive prehistoric RF agriculture. In this region RF is organized in ‘block groups’ in which adjacent beds share a similar orientation and size. These block groups are organized across the landscape in a manner that might correspond to social organization and labor distribution. Aerial surveys estimate that the region hosts some 40,000 large raised field beds over an area 7,500 square kilometers. In this region RF is organized in ‘block groups’ in which adjacent beds share a similar orientation and size. These block groups are organized across the landscape in a manner that might correspond to social organization and community labor distribution. Further archaeological excavation has indicates that the use of RF began around 600 AD and possibly continued until 1800 AD.

See work by Denevan (esp for the early Jesuit numbers as well)

Chile
Martín, J.G.; Mendizábal, T.; Schreg, R.; Cooke, R.G.; Piperno, D. Pre-Columbian raised ﬁelds in Panama: First evidence. J. Archaeol. Sci. Rep. 2015, 3, 558–564. [CrossRef]

Altiplano (highland Bolivia and Peru)
Main Article: Waru waru

The land around Tiwanaku, the civic-ceremonial center inhabited from approx 250 BC to 1100AD (with a peak between 600 AD-1000 AD) on the shoreline of Lake Titicaca in Bolivia contains many examples of RF. Archaeologists theorize that RF was used to make viable farmland from an area whose average annual temperature is 7 degrees Celsius, as the raised beds were able to trap heat more efficiently than regular fields and prevent crops from freezing. RF also provided the fields with a dependable water supply, which was crucial as the water level in the lake fluctuated fairly frequently. Alan Kolata proposed that the heat-trapping properties of the beds and the plentiful supply of fertile soil extended the altiplano growing season up to two months, which enabled farmers to use a “double cropping” agricultural model. Double cropping is a type of polyculture in which two or more crops are grown sequentially in the same bed during a single growing season.

Current GIS and land surveys have estimated that some 120,000 hectares of raised field systems were built in the area around Lake Titicaca in prehistoric times, although they have been alternatively eroded and filled sediment due to a variety of human and environmental factors. Energetic s estimates that the total energy expended by a single family to construct the RF around the lake was up to 200 times greater than the energy expended to construct the ceremonial and administrative centers.

Archaeological excavations indicate that the use of raised field agriculture around Lake Titicaca originates with the Pukara polity (1000 to 300BC) on the northern shore. As the polity's influence declined into the first millennia and Tiwanaku grew in power, the northern raised fields were gradually abandoned. Tiwanaku utilized RF on the south side of the lake, but after the civic-ceremonial site collapsed only some RF were restabled before the Inca arrived to the area in 1450 AD. Clarke Erickson suggests that this data indicates that raised field practices developed to keep up with the growing ceremonial influence of Tiwanaku, rather than be a driving factor.

Controversy
The “Raised Field Debate” in Andean archaeology refers to the discourse on the extent to which raised fields were a product of “top-down” authority or “bottom-up” local innovation. Erickson’s work in the northern basin of the lake led him to conclude that elites “never ‘tampered with’ ancient raised field systems” and the lower-level organization of raised field agriculture allowed for survival despite turbulent political surroundings. In contrast, Kolata’s work in the south basin convinced him that Tiwanaku rulers had a managerial role in the creation and maintenance of the extensive raised field system. Standish’s work in the southwestern basin led to a similar conclusion that raised fields were an “economic strategy employed by elite groups to maximize wealth extraction from subject populations." These scholars studied the spatial layout of the raised fields, their relative construction and use chronologies, and artifact assemblages to support their conclusions. Regardless, each scholar agrees that RF was a subsistence strategy used by Altiplano farmers to maximize their crop production.

Central America
Main article: chinampas

In the Basin of Mexico RF is referred to as chinampas. Originally associated with the Maya, this practice is still in use in some lakes in the region. Aerial surveys in the late 20th century confirmed the existance of at least 3200 hectares of RF in Belize, 400 square kilometers in Quintana Roo of southern Mexico. RF varies in both shape and size, although the beds have hierarchical organization and the quadrilateral bed shape in the center of the field becomes more amorphous towards the edge of the fields.

31. Torres-Lima, P.; Canabal-Cristiani, B.; Burela-Rueda, G. Urban sustainable agriculture: The paradox of the chinampa system in Mexico City. Agric. Hum. Values 1994, 11, 37–46. [CrossRef]

32. Baveye, P.C. Comment on “Ecological engineers ahead of their time: The functioning of pre-Columbian raised-ﬁeld agriculture and its potential contributions to sustainability today” by Dephine Renard et al. Ecol. Eng. 2013, 52, 224–227. [CrossRef]

33. Chapin, M. The seduction of models. Chinampa agriculture in Mexico. Grassroots Dev. 1988, 12, 8–17. [PubMed

Panama
Martín, J.G.; Mendizábal, T.; Schreg, R.; Cooke, R.G.; Piperno, D. Pre-Columbian raised ﬁelds in Panama: First evidence. J. Archaeol. Sci. Rep. 2015, 3, 558–564. [CrossRef]

Asia
Insert information about Asia here******

Congo Basin
RF is used throughout the Congo Basin in conjunction with other agricultural practices. The cultivation of these fields is predominately done by women. Each RF is typically used for 5-6 years (producing three or four harvests) and then left fallow for two to four years before rejuvenating the soil with material from the channel bottom. Manoic planted in RF can be left unharvested in the beds for three to four years, acting as live storage and a safety net in the case of environmental or economic difficulties.

RF in the low-lying and flood-prone cuvette centrale of the Congo Basin comes in four main types: circular (lianga), horseshoe or crown (milingu), ridged ( mondezeke or mosambuku), and crescent (mombaka). The horseshoe or crown shaped fields double as fish traps, as fishermen place basket traps on the opening of the plot during the end of the rainy season when the water level recedes.

Ethnographic interviews indicate that the use of RF in the region has been declining since the 1980s as it is superseded by fishing and other less productive but less labor intensive agricultural practices such flood regressional agriculture.

Amazonia
After the Spanish conquest in the 1500s, RF remained in limited use in parts of the Amazon region. Creole farmers created small fields of RF in forested areas of the Guianas coasts that continued to be farmed by Saramaka and Haitian immigrants. In recent years there have been initaitives by ecosystem engineers to restore abandoned and erroded RF beds in order to cultivate them once more. The recultivation of these beds originally produced a high yeild, but diminishing returns after five years led farmers to diversify and leave the fields fallow for a year or so to replenish their nutrients. similar efforts to reintroduce RF to the Amazonian region

Altiplano
While it is difficult to identify the precise time RF fell out of favor in the Altiplano, the lack of mention of RF in the 16th century Spanish chronicles of the conquest of the Altiplano indicates that raised fields were abandoned before the Spanish arrived in 1532. Up until the late 20th century, RF was not practiced in the Altiplano. However, Archaeological research programs from the University of Pennsylvania and the University of Chicago was coupled with an initiative to reintroduce raised field agricultural practices to the region’s inhabitants in the 1980s.

Erickson's Raised Field Agricultural Project (RFAP) began in 1982. The RFAP derived bed measurements from excavated fields, reconstructed raised fields, and planted potatoes, quinua, and cañihua. Over a five year period, the potato yield of these beds was an average of 10 metric tons per hectare. This figure, grown without fertilizer, was much higher than the 1 to 4 metric tons per hectare reported to the Department of Puno for traditional plant beds. The project’s success in this time led Erickson to conclude that raised fields allowed for high yields on the same bed despite continuous cropping, as the nutrients of the beds can easily be replenished by the addition of canal sediment. According to his measurements, RF beds fared much better than traditional fields during frosts such as that of the winter of 1982, as the water surrounding the beds stored heat that was then gradually released into the surrounding soil.

These initiatives in the mid-1980s should be placed within the context of globalization and industrial farming. At this time there were numerous projects by governments, NGOs, and private companies to increase the agricultural output of the altiplano through “petro-chemical fertilizers, heavy farm machinery, imported seed, irrigation pumps, or special animal forage." These projects were expensive, oriented towards cash crops, and inaccessible to small-scale farmers. The initiatives by Erickson and Kolata, and their eventual partnerships with both governmental and non-governmental organizations, mix the boundaries of experimental archaeology and activist anthropology in the face of larger capitalist agendas, but in their own small way play into the Western savior complex. Long-term efforts to rehabilitate the RF system were crippled by many factors. Competing labor demands, traditional fallow cycles, crop genetic loss, land tenure issues, livestock competition, limited technical knowledge by NGOs, political unrest, tension between individual and community farming, and misuse of  government incentives to adopt the practice all underline that fact that RF agriculture in the Andes was a product of a very socio-cultural context. Raised fields also became a political chess-piece within the local communities’ efforts to reclaim traditional lands from the government.

Environmental impact
RF is an environmentally sustainable way to use wetlands. It is an agricultural practice that preserves various ecosystems as it does not drain, pollute, or disrupt the flow of water where it is built. By adjusting the height of the bed, farmers are able to plant at the highest expected flood level and thus better shelter their plants from excessive rain than other types of traditional agriculture. It also promotes biodiversity and in some cases has been observed to increase the pollen count of nearby plants.

World Heritage classification
Scholars such as Erickson (2003) believe that traditional agricultural landscapes contain the “ the cultural context for living, historical, and archaeological indigenous belief systems” and should thus be protected as world heritage sites.The categorization of RF as such is difficult, as agricultural lands are dynamic spaces that undergo constant modification and maintenance. This lack of stasis is unlike many other world heritage site....

In addition, studies have revealed that landscapes previously thought to be "pristine" and unmodified by human activity such as the Amazonian Basin have in fact been managed and farmed for centuries. Inhabitants of the area used RF and many other agricultural activities to foster biodiversity and multiple subsistence systems.