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Oxygen isotopes in cellulose identify source water for archaeological maize in the American Southwest [An article from: Journal of Archaeological Science]
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Oxygen isotopes in cellulose identify source water for archaeological maize in the American Southwest [An article from: Journal of Archaeological Science] | Digital

by D.G. Williams (Author), J.B. Coltrain (Author), M. Lott (Author), N. English (Author)

List Price: $7.95  
Available:  Available for download now

Binding:  Digital
Publisher:  Elsevier
Publication Date:  June 01, 2005


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Product Description
This digital document is a journal article from Journal of Archaeological Science, published by Elsevier in 2005. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.Description: Maize (Zea mays) was a primary food crop for aboriginal societies of the arid American Southwest. Water used for maize production in these arid zones could have come from precipitation and runoff during the summer monsoon, from perennial streams and springs, or from stored soil water fed by snowmelt. The oxygen stable isotope ratio (@d^1^8O) of summer and winter precipitation on the Colorado Plateau naturally differ by more than 10%% providing a powerful tool for distinguishing winter- from summer-derived water sources used in cultivation of maize. We investigated whether variation in @d^1^8O of potential source waters is preserved in the @d^1^8O of cellulose (@d^1^8O"c"e"l"l"u"l"o"s"e) of maize cobs by growing four aboriginal and one modern maize variety in pots irrigated with water of known @d^1^8O composition. The @d^1^8O"c"e"l"l"u"l"o"s"e values of cobs ranged from 26.8 to 36.4%% (averaged within varieties) and were highly correlated with @d^1^8O values of the source irrigation water (-15.8 to -8.2%%). Cob @d^1^8O"c"e"l"l"u"l"o"s"e from five archaeological sites on the Colorado Plateau in southeastern Utah ranged from 27.3 to 34.6%%, closely matching the range of values observed in experimental plants. A @d^1^8O"c"e"l"l"u"l"o"s"e model developed originally for tree rings was parameterized and applied to the archaeological maize cobs. The model indicated that monsoonal precipitation accounted for 0-20% of the moisture for archaeological cob samples from a site adjacent to a perennial stream and 43-98% for samples from an upland site, more distant from a perennial water source. These results reveal the potential for using @d^1^8O"c"e"l"l"u"l"o"s"e to investigate prehistoric irrigation practices and source water used for maize production in the American Southwest.
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