@proceedings {KNZ00375,
	title = {Effects of tallgrass prairie vegetation on the concentration and seasonality of nitrate\-nitrogen in soil water and streams},
	year = {1992},
	pages = {9 -12},
	publisher = {University of Northern Iowa},
	abstract = {<p>Inorganic nitrogen concentrations in tallgrass prairie soils and streams exhibit a sinusoidal seasonal pattern; nitrate levels are relatively high in winter and low in summer. The pattern is not observed in either rainfall or canopy drip (throughfall). Thus, the pattern is created by plant root-microbial interactions; when roots are not active, nitrates accumulate and can be leached from the soil. We used nitrogen fertilizer and herbicide in a factorial experiment to test the strength of root uptake activities on soil water nitrogen. Soil-water nitrate concentrations were 10 times higher when prairie roots were deactivated by application of a foliar herbicide. Ammonium nitrogen concentrations were unaffected. When fertilizer was added, nitrate levels of soil water beneath herbicide-treated vegetation were double that of untreated prairie. Mineralization of nitragen from herbicide-treated roots was not believed to be the source of the increased nitrate. These and previous studies at Konza Prairie emphasize the importance of plant cover in maintaining low nitrate concentrations of streams</p>},
	keywords = {LTER-KNZ, tallgrass prairie},
	author = {Ramundo, R.A. and Tate, C.M. and Seastedt, T.R.},
	editor = {Smith, D.A. and Jacobs, C.A.}
}
@proceedings {KNZ00350,
	title = {Population ecology of thirteen-lined ground squirrels in ungrazed tallgrass prairie manipulated by fire},
	year = {1992},
	pages = {51 -54},
	address = {University of Northern Iowa},
	abstract = {<p>From March 1983 to October 1987, thirteen-lined ground squirrels (Spermophilus tridecemlineatus Mitchill) were studied in ungrazed tallgrass prairie manipulated by fire on the Konza Prairie Research Natural Area, Kansas. Overall abundance varied among years (2.6 animals/ha in 1985; 5.6 animals/ha in 1986); however, no significant variation in sex ratio was observed (overall average=52\% males for adults, 48\% males for juveniles). Fire had a positive effect on ground squirrels; abundance was significantly higher in burned than unburned prairie during the year of a fire and in more recently than less recently burned prairie during years following a fire. Ground squirrels also selected hillsides with exposed rocks (breaks) over upland and lowland prairie sites. Although females and males selected similar habitats, home ranges were significantly larger for adult males (average=0.56 ha) than for adult females (0.36 ha). Both adult females and males caught on the study area typically were residents rather than transients. Further, overwinter survival did not differ between adult females and males. Overwinter survival of juvenile females was similar to adults; however, no juvenile males overwintered on the study area</p>},
	keywords = {LTER-KNZ, tallgrass prairie},
	author = {Clark, B.K. and D.W. Kaufman and Kaufman, G.A. and Gurtz, S.K. and Bixler, S.H.},
	editor = {Smith, D.A. and Jacobs, C.A.}
}
