Article ID Journal Published Year Pages File Type
4393659 Journal of Arid Environments 2010 6 Pages PDF
Abstract

Pollen analysis of two woodrat middens from Hueco Tanks, El Paso County, Texas, dated 10,140 ± 70 and 7170 ± 70 14C years BP, shows late persistence of the regional glacial-age Artemisia steppe vegetation in what is historically desert shrub grassland of the northern Chihuahuan Desert. Local populations of Pinus were gone by the end of the Pleistocene, and creosotebush (Larrea) and mesquite (Prosopis) appeared in the local vegetation by mid-Holocene time. Juniperus can be strongly over-represented in midden pollen assemblages due to harvesting of cone-bearing twigs by woodrats. AMS radiocarbon dates on very small samples of midden matrix used for pollen analysis are 3400 and 2200 14C years younger than dates on plant macrofossils from the same middens. Juniperus over-representation in pollen percentages and age differences between pollen and macrofossil content must be taken into account when interpreting the palynology of woodrat middens.

Related Topics
Physical Sciences and Engineering Earth and Planetary Sciences Earth-Surface Processes
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