TY - JOUR
T1 - Pollen in packrat middens
T2 - The contribution of filtration
AU - O’Rourke, Mary Kay
N1 - Funding Information:
The research was supported in part by a Desert hluseum Research Grant to Thomas R. Van Devender and hlary Kay ORourke. Thanks ace due to Owen K. Davis for use of the pollcn extraction laboratory, Donna Howell for counting pollen samples. Paeter K. Van dc Water for photographing the plant surfaces and to Paul S. hiartin and Peter K. Van dc Water who reviewed a preliminary draft of the manuscript.
PY - 1991
Y1 - 1991
N2 - Fossil packrat middens are used to reconstruct late Quaternary environments in the arid Western U.S.A. Airborne pollen is contributed to middens both directly from the air, and through adherence to plant macrofossils. I examined the filtration of atmospheric pollen by Larrea iridenata leaves (resinous, with sparse recumbent hairs), Cercidium microphyllum twigs (glabrous with recumbent hairs) and Sphaeralcea ambigua leaves (covered with stellate hairs) and evaluated the potential biases of scavenged pollen on the interpretation of pollen records from middens. Pollen grains collected from the surfaces of the plants were most numerous during the spring when (airborne) pollen concentrations were high. Of the species investigated, the Sphaeralcea leaves filtered the greatest number of spring pollen grains from the air (3419 grains cm-2); captured pollen was very low during other seasons. Sticky Larrea leaves continuously captured airborne pollen (X̄ = 246 grains cm-2). Pollen captured by smooth Cercidium was consistently low (X̄ = 31 grains cm-2). Only the spring pollen was filtered in sufficient numbers to obtain minimum pollen counts of 200 grains by all 3 taxa. The plants frequently captured greater proportions of their own pollen. Pollen content of packrat middens will reflect the season of plant macrofossil collection and the species composition of the plants incorporated.
AB - Fossil packrat middens are used to reconstruct late Quaternary environments in the arid Western U.S.A. Airborne pollen is contributed to middens both directly from the air, and through adherence to plant macrofossils. I examined the filtration of atmospheric pollen by Larrea iridenata leaves (resinous, with sparse recumbent hairs), Cercidium microphyllum twigs (glabrous with recumbent hairs) and Sphaeralcea ambigua leaves (covered with stellate hairs) and evaluated the potential biases of scavenged pollen on the interpretation of pollen records from middens. Pollen grains collected from the surfaces of the plants were most numerous during the spring when (airborne) pollen concentrations were high. Of the species investigated, the Sphaeralcea leaves filtered the greatest number of spring pollen grains from the air (3419 grains cm-2); captured pollen was very low during other seasons. Sticky Larrea leaves continuously captured airborne pollen (X̄ = 246 grains cm-2). Pollen captured by smooth Cercidium was consistently low (X̄ = 31 grains cm-2). Only the spring pollen was filtered in sufficient numbers to obtain minimum pollen counts of 200 grains by all 3 taxa. The plants frequently captured greater proportions of their own pollen. Pollen content of packrat middens will reflect the season of plant macrofossil collection and the species composition of the plants incorporated.
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U2 - 10.1080/00173139109431988
DO - 10.1080/00173139109431988
M3 - Article
AN - SCOPUS:0026363835
VL - 30
SP - 337
EP - 341
JO - Grana
JF - Grana
SN - 0017-3134
IS - 2
ER -