| Summary: | A Thesis [dissertation] submitted to the faculty of the Graduate School of the University of Minnesota by James Kenneth Huber in partial fulfillment of the requirements for the degree of Doctor of Philosophy, January 2001. Plates 1-11 referenced in the thesis are also attached to this record. Four pollen sequences, from Big Rice, Cloquet, Gegoka, and East Bearskin lakes in northeast Minnesota indicate that postglacial vegetation progressed from tundra to a shrub parkland or forest-tundra to a conifer-hardwood forest to a mixed conifer-hardwood forest and to an uppermost ragweed zone that indicates Euro-American settlement and deforestation beginning about 1890. Based on the abundance of Gramineae pollen in the Big Rice Lake pollen sequence, wild rice (Zizania aquatica) is present in harvestable quantities approximately 1,600 years before its known use in a Laurel occupation at the Big Rice archaeological site. Pollen data from the uppermost sediment of Shannon Lake suggest that Gramineae abundance data may not indicate the presence of substantial wild rice beds in bays and shallows of lakes with large areas of deep open water. The Gramineae pollen profile from Gegoka Lake, which now supports wild rice over most of its surface, indicates that the current presence of wild rice in some lakes may be a relatively recent event. Nonsiliceous algae recovered in conjunction with pollen from Big Rice, Cloquet, Gegoka, and East Bearskin lakes indicate that each lake has undergone cycles of nutrient enrichment. Changing environmental or limnologic competition, or both, as well as competition by macrophytic vegetation, is indicated by oscillations in nonsiliceous algae abundance. Gramineae abundance data and Gramineae pollen grain size distribution data indicate that wild rice was probably present in harvestable quantities in northeast Minnesota in late Paleoindian times and has persisted up to the present. Gramineae pollen grain size distribution data was especially useful in identifying the probable presence of ...
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