@article {KNZ001768,
	title = {High dissimilarity within a multiyear annual record of pollen assemblages from a North American tallgrass prairie},
	journal = {Ecology and Evolution},
	volume = {6},
	year = {2016},
	pages = {5273 - 5289},
	abstract = {<p>Grassland vegetation varies in composition across North America and has been historically influenced by multiple biotic and abiotic drivers, including fire, herbivory, and topography. Yet, the amount of temporal and spatial variability exhibited among grassland pollen assemblages, and the influence of these biotic and abiotic drivers on pollen assemblage composition and diversity has been relatively understudied. Here, we examine 4 years of modern pollen assemblages collected from a series of 28 traps at the Konza Prairie Long-Term Ecological Research Area in the Flint Hills of Kansas, with the aim of evaluating the influence of these drivers, as well as quantifying the amount of spatial and temporal variability in the pollen signatures of the tallgrass prairie biome. We include all terrestrial pollen taxa in our analyses while calculating four summative metrics of pollen diversity and composition \&ndash; beta-diversity, Shannon index, nonarboreal pollen percentage, and Ambrosia:Artemisia \&ndash; and find different roles of fire, herbivory, and topography variables in relation to these pollen metrics. In addition, we find significant annual differences in the means of three of these metrics, particularly the year 2013 which experienced high precipitation relative to the other 3 years of data. To quantify spatial and temporal dissimilarity among the samples over the 4-year study, we calculate pairwise squared-chord distances (SCD). The SCD values indicate higher compositional dissimilarity across the traps (0.38 mean) among all years than within a single trap from year to year (0.31 mean), suggesting that grassland vegetation can have different pollen signatures across finely sampled space and time, and emphasizing the need for additional long-term annual monitoring of grassland pollen.</p>},
	keywords = {LTER-KNZ, fire, grassland, Great Plains, Herbivory, Pollen, Tauber traps},
	doi = {10.1002/ece3.2259},
	url = {https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.2259},
	author = {Commerford, J.L. and McLauchlan, K.K. and Minckley, T.A.}
}
@phdthesis {KNZ001784,
	title = {Investigating North American grassland biogeography throughout the Holocene},
	volume = {PhD Dissertation},
	year = {2016},
	school = {Kansas State University},
	type = {Ph.D. Thesis},
	address = {Manhattan, KS},
	keywords = {LTER-KNZ},
	url = {http://krex.k-state.edu/dspace/handle/2097/32798},
	author = {Commerford, J.L.}
}
@mastersthesis {KNZ001305,
	title = {Calibrating vegetation cover and pollen assemblages in the Flint Hills of Kansas, USA},
	volume = {MS Thesis},
	year = {2010},
	school = {Kansas State University},
	type = {M.S. Thesis},
	address = {Manhattan, KS. 73 pp},
	abstract = {<p>The quantitative relationship between pollen assemblages in sediment and vegetation cover is largely unknown because many factors influence this relationship. This lack of quantitative relationship is particularly acute in grassland regions, where both past and future climate change have the potential to determine grassland composition and cover. The tool used to reconstruct past grassland cover is the relative abundance of distinct fossil pollen types preserved in sediment. However, the interpretation of grassland pollen assemblages as grassland vegetation types needs to be refined to improve these reconstructions. Using pollen found in the surface sediments from 24 artificially-constructed ponds in the Flint Hills ecoregion of Kansas, USA, I examined relationships between pollen and vegetation in the tallgrass prairie biome, which includes woody components. By comparing the pollen data to field-surveyed vegetation data and land cover classifications taken from Kansas Gap Analysis Program data, I correlated pollen and vegetation in this ecoregion. Pollen productivity estimates for Artemisia, Ambrosia, Asteraceae, Chenopodiaceae, Cornus, Fabaceae, Juniperus, Maclura, Poaceae, Populus, Quercus, and Salix were calculated via the Extended R-Value Model. Common pollen types identified in sediments are mostly herbaceous grassland plant species such as Poaceae, Artemisia, and Ambrosia, but woody plants such as Populus, Quercus, and Juniperus are also represented. PPEs have been calculated for four of these taxa in Europe, and values from the Flint Hills are higher. These are the first PPEs reported for eight of these taxa. This research will further advance quantitative vegetation reconstructions in the Great Plains of North America and refine interpretations of how climate change affects grasslands.</p>},
	keywords = {LTER-KNZ, grassland, Kansas- Flint Hills, Pollen, prairie vegetation},
	url = {http://hdl.handle.net/2097/4170},
	author = {Commerford, J.L.}
}
