TY - Generic T1 - Bryopyhtes on Konza Prairie Research Natural Area Y1 - 1989 A1 - Merrill, G.L. ED - Bragg, T.B. ED - Stubbendieck, J. KW - tallgrass prairie AB -

Fifty-eight species of mosses (37 genera, 18 families) and 4 species of liverworts (3 genera, 3 families) are reported from Konza Prairie Research Natural Area, a 3,487- hectare tallgrass prairie preserve in northeastern Kansas. Factors affecting the growth and persistence of bryophytes on the prairie are discussed. The occurrence of bryophytes in presettlement tallgrass prairies was probably influenced by natural disturbance due to grazing and recurring fire

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Correlations between stream insect emergence and densities of insectivorous birds in the tallgrass prairie Y1 - 1989 A1 - Gray, L.J. ED - Bragg, T.B. ED - Stubbendieck, J. KW - tallgrass prairie AB -

Previous observations in riprarian habitats of Kings Creek, Konza Prairie Research Natural Area, Kansas indicated that emerging aquatic insects represent a concentrated source of food for insectivorous birds, particularly the flycatcher and gleaner guilds. This hypothesis was tested by concurrent measurments of net insect emergence (total emergence minus adults returning to the stream) and densities of birds at six sampling sites from June to August 1987 and May to June 1988. Significant positive correlations with emergence were found for flycatchers (r=0.93) and gleaners (r=0.91), the two insectivore guilds containing the majority of individuals along Kings Creek. Observations also showed that flycatcher and gleaner populations rapidly respond to temporal changes in insect emergence. Key words: fly catcher, gleaner, bird, aquatic insect, tallgrass prairie, stream, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Effects of manipulation on foliage characteristics of Andropgon gerardii Vitman Y1 - 1989 A1 - Ramundo, R.A. A1 - Shapley, T.D. A1 - Turner, C.L. A1 - Dyer, M.I. A1 - Seastedt, T.R. ED - Bragg, T.B. ED - Stubbendieck, J. KW - burning AB -

The effects of burning, mowing, and nitrogen fertilizer on the chlorophyll, nitrogen, and phosphorus content of big bluestem were measured using a factorial experimental design at Konza Prairie Research Natural Area. While spring burning usually increased foliage production, burning had no effect on mid-season chlorophyll or nitrogen concentrations. Chlorophyll concentrations were significantly increased by fertilizer and mowing treatments. Nitrogen concentrations of foliage were higher on fertilized and mowed plots. Mowing also increased phosphorous concentrations of foliage, but nitrogen fertilizer significantly reduced phosphorus concentrations. These results support other research indicating that 1) nitrogen use efficiency (grams biomass produced per gram of foliage nitrogen) is higher on burned prairie, 2) removal of foliage by mowing results in more nutrient-rich regrowth, and 3) the amount of phosphorus available to big bluestem foliage is limited. The dilution of phosphorus caused by added nitrogen was a consequence of increased productivity on these plots and suggessts phosphorus uptake in excess of requirements for maximum growth. The relationships between burning, mowing, and nitrogen on the spectral reflectance patterns of vegetation indicated that chlorophyll (or nitrogen) concentrations of foliage appeared to more strongly affect indices of greenness and plant vigor than did the amount of plant biomass. Key words: biomass, burning, mowing, big bluestem, Andropogon gerardii, chlorophyll, nitrogen, phosphorus, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Is fire a disturbance in grasslands? Y1 - 1989 A1 - Evans, E.W. A1 - Finck, E.J. A1 - J. M. Briggs A1 - D.J. Gibson A1 - James, S.W. A1 - D.W. Kaufman A1 - Seastedt, T.R. ED - Bragg, T.B. ED - Stubbendieck, J. KW - fire AB -

Many grasslands, and in particular the tallgrass prairies of North America, are generally thought to be maintained by periodic fire. Semantic disagreement among researchers, however, threatens to hamper discussion of fire as an ecological force in grassland ecosystems. Some authors emphasize that fires are disturbances (or perturbations) since these fires disrupt or alter ecosystem states, trends and dynamics (e.g., accumulating nitrogen is volatilized, plant and animal communities change in composition). Other researchers point out that, because these fire-induced disruptions and alterations can maintain the status quo of the ecosystem (e.g., prevent it from becoming woodland), it is the lack of fire rather than fire itself that should be considered a disturbance. We argue that, since both points of view are useful, there is little to be gained by labeling loosely either fire or lack thereof as a "disturbance" in grassland ecosystems. Key Words: disturbance, fire, grasslands, perturbation, prairie, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Hulbert's study of factors effecting botanical composition of Tallgrass Prairie Y1 - 1989 A1 - D.J. Gibson ED - Bragg, T.B. ED - Stubbendieck, J. KW - tallgrass prairie AB -

Lloyd Hulbert's death in May 1986 left a wealth of unfinished projects as well as the legacy of Konza Prairie Research Natural Area, Kansas. One of these was an incomplete manuscript on fire, mowing, and soil effects on the tallgrass prairie, in which canopy cover and frequency in 27 soil-treatment combinations from Konza Prairie were reported. Treatments included unburned and April burned at 1-, 2-, and 4-year intervals, annual burning during three seasons, and mowing during two seasons. Soils ranged from deep and non-rocky to shallow, rocky, silty clay loams. Late April burning favored tall C4 grasses at the expense of most forbs, whereas autumn and March burning allowed many forbs to do well. More species occurred on shallow, rocky soils than on deep soils. Annuals and biennials succeeded in mowed areas but not in burned areas. Tables of partially summarized data are included with this report so that other researchers may make use of them. Key words: tallgrass prairie, fire, mowing, soil, plant communities, species richness, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Landsat thematic mapper digital data for predicting aboveground biomass in a tallgrass prairie ecosystem Y1 - 1989 A1 - J. M. Briggs A1 - Nellis, M.D. ED - Bragg, T.B. ED - Stubbendieck, J. KW - tallgrass prairie AB -

Landstat thematic mapper digital data was found to offer an excellent potential for regular monitoring of the tallgrass prairie ecosystem by providing estimates of aboveground biomass production. Data from several channels of a May thematic mapper scene were analyzed individually and in various combinations using stepwise regression in Statistical Analysis System (SAS). These procedures were used to determine the most appropriate multiple regression equation for estimating production of 1) total live aboveground biomass, 2) grasses, 3) forbs, 4) previous years dead, and 5) current years dead. Regression equations were based on satellite-derived estimates relative to ground level biomass values for watersheds on Konza Prairie Research Natural Area under a variety of burning treatments. Results suggest that multiple channel equations were most appropriate for measuring production of forbs and total live aboveground biomass. Channel one (0.45 to 0.52 æmeters) and channel four (0.76 to 0.90 æmeters) were applicable to estimate production of grass and levels of previous years litter, respectively. However, none of the channels were accurate in predicting current years dead. Further plans involve using thematic mapper data to estimate aboveground biomass over an entire growing season on Konza and exploring the potential of using satellite data to monitor grassland production across the Great Plains. Key Words: tallgrass prairie, remote sensing, aboveground biomass, Landstat, thematic mapper, monitoring, Konza Prairie, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Polyploid polymorphism in the prairie grass big bluestem (Andropogon gerardii) Y1 - 1989 A1 - Keeler, K.H. A1 - Kwankin, B. ED - Bragg, T.B. ED - Stubbendieck, J. AB -

A suprising number of plant species contain individuals of a variety of levels of polyploidy, so that the species is polymorphic for polyploidy. This paper considers possible general causes for this phenomenon in plants of the Great Plains of North America. First we compared the frequency of intraspecific polyploidy in three major plant families, Poaceae, Asteraceae, and Fabaceae. The majority of grass species (Poaceae) and the minority of composite and legume species (Asteraceae and Fabaceae) are polyploid polymorphic. The frequency of grass species with intraspecific polyploidy suggests shared causatin or at least shared tolerance of this character. Having established that the situation occurs frequently in grasses, we analyzed a single species, big bluestem, Andropogon gerardii, looking for information on the function of polyploid polymorphism. We used flow cytometry to determine amount of nuclear DNA per cell; In big bluestem this correlates with chromosome number. Individuals with 7 pg nuclear DNA had 2N=60 chromosomes, and were therefore hexaploid, since in Andropogon x=10. Most other individuals had approximately 10 pg nuclear DNA and 80 (occasionally 90) chromosomes. Seven-pg DNA individuals were predominatnt everywhere, but the frequency of higher polyploids (10 pg nuclear DNA) went from virtually 0 on the eastern end of the tallgrass prairie region to 40% at the western end. Within native prairies in the west, the full range of variation existed between sites. A recent origin for polyploid polymorphism is suggested in big bluestem and probably other Great Plains grasses, and the data seem most compatible with a transitional situation, although other explanations cannot be ruled out

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Rodents and shrews in ungrazed tallgrass prairie manipulated by fire Y1 - 1989 A1 - D.W. Kaufman A1 - Kaufman, G.A. A1 - Finck, E.J. ED - Bragg, T.B. ED - Stubbendieck, J. KW - tallgrass prairie AB -

Natural Prairie was a mosaic of patches of depths of plant litter due to topoedaphic conditions and to spatial-temporal variation in fire and grazing. Such variation in litter depth undoubtedly influenced the distribution and abundance of small mammals. To examine this issue, small mammals were censused and plant litter depth was measured during autumn from 1981 to 1984 on the Konza Prairie Natural Research Area near Manhattan, Kansas. Five to 11 sites subjected to fire at different times from 1967 to 1984 were sampled during each of the four years of the study. Relative densities of deer mice (Peromyscus maniculatus) were negatively correlated to litter depth, wheras relative densities of Elliot's short-tailed shrews (Blarina hylophaga) and western harvest mice (Reithrodontomys megalotis) were positively correlated to the depth of plant litter. White-footed mice (Peromyscus leucopus), typically found in wooded and brushy habitats, were captured in prairie sites, but no significant association with plant litter was evident. Although prairie voles (Microtus ochrogaster) were expected to be positively associated with litter, no significant relationship was found for 1982 (the only year with sufficiently high densities to test for a possible pattern). Key words: small mammals, plant litter, tallgrass prairie, fire, rodents, shrews, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER - TY - Generic T1 - Silica, nitrogen and phosphorus dynamics of tallgrass prairie Y1 - 1989 A1 - Seastedt, T.R. A1 - Ramundo, R.A. A1 - Hayes, D.C. ED - Bragg, T.B. ED - Stubbendieck, J. KW - tallgrass prairie AB -

Experiments were conducted on big bluestem (Andropogon gerardii Vitman) in the greenhouse and on a tallgrass site on Konza Prairie to evaluate the effects of simulated grazing on the cycling of silica (SiO2), nitrogen, and phosphorus. Concentrations of all elements increased in vegetation that had been clipped or pruned. The absolute amount of nitrogen obtained by plants in the greenhouse experiment was increased by clipping foliage. Phosphorous exhibited only neutral or negative responses, while the absolute amount of silica declined in all but one experiment involving root pruning. In that experiment, the absolute amount of silica in roots was increased by 25% by cutting a portion of the root system. These results suggest that the direct effects of clipping or pruning on the absolute amounts of elements cycled through vegetation are usually neutral or negative. Increased silicification or grazed foliage is suggested to be a consequence of delayed senescence and reduced leaf area. This interpretation provides a proximate reason why silicification is an "inducible defense" against herbivores. Key words: big bluestem, Andropogon gerardii, simulated grazing, nutrients, productivity, roots, Kansas

PB - University of Nebraska Press CY - Lincoln, NE ER -