02404nas a2200229   4500008004100000245015000041210006900191300001100260490000700271520161900278653002401897653001801921653001901939653001601958653002801974653002302002653002202025100001802047700001502065700001702080856007702097       2011                        eng d00aIntraspecific Variation in Ecophysiology of Three Dominant Prairie Grasses Used in Restoration: Cultivar Versus Non‐Cultivar Population Sources0 aIntraspecific Variation in Ecophysiology of Three Dominant Prair  a43 -520 v193 a<p>Dominant species play crucial roles in determining plant community structure and ecosystem function. Cultivars of the dominant prairie grasses are widely used in prairie restoration and are selected for characters such as high biomass production, increased reproductive output, and stress tolerance. Genetic differences exist between cultivar and non-cultivar population sources of dominant tallgrass prairie species, which may have implications for plant performance in prairie restoration. We measured net photosynthesis (Anet), stomatal conductance (gs), and water use efficiency (WUE) in cultivar and non-cultivar dominant tallgrass prairie species Andropogon gerardii Vitman, Sorghastrum nutans (L.) Nash, and Schizachyrium scoparium (Michx.) Nash in both a greenhouse experiment and an experimental tallgrass prairie restoration. We found indicators of enhanced physiological performance (higher Anet, gs, and/or WUE) in cultivar population sources of all three dominant grass species relative to non-cultivars. For A. gerardii, cultivars exhibited higher Anet and WUE than non-cultivars. For S. nutans, cultivars exhibited higher gs, whereas non-cultivars showed higher WUE. Lastly, cultivars of S. scoparium showed higher WUE than non-cultivar population sources. Our results show that population selection of dominant species in restoration can have consequences for plant performance, which may have implications for competitive interactions that affect community structure (i.e. diversity) and ecosystem function (i.e. aboveground net primary production) during the reassembly of prairie systems.</p>10aAndropogon gerardii10aEcophysiology10aphotosynthesis10arestoration10aSchizachyrium scoparium10aSorghastrum nutans10atallgrass prairie1 aLambert, A.M.1 aBaer, S.G.1 aGibson, D.J.  uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1526-100X.2010.00673.x02307nas a2200241   4500008004100000245010400041210006900145300001300214490000700227520153700234653002401771653002401795653002201819653001001841653001601851653002301867100002301890700001401913700001901927700002001946700001601966856008301982       2009                        eng d00aEcophysiological responses of two dominant grasses to altered temperature and precipitation regimes0 aEcophysiological responses of two dominant grasses to altered te  a400 -4080 v353 a<p>Ecosystem responses to climate change will largely be driven by responses of the dominant species. However, if co-dominant species have traits that lead them to differential responses, then predicting how ecosystem structure and function will be altered is more challenging. We assessed differences in response to climate change factors for the two dominant C4 grass species in tallgrass prairie, Andropogon gerardii and Sorghastrum nutans, by measuring changes in a suite of plant ecophysiological traits in response to experimentally elevated air temperatures and increased precipitation variability over two growing seasons. Maximum photosynthetic rates, stomatal conductance, water-use efficiency, chlorophyll fluorescence, and leaf water potential varied with leaf and canopy temperature as well as with volumetric soil water content (0&ndash;15 cm). Both species had similar responses to imposed changes in temperature and water availability, but when differences occurred, responses by A. gerardii were more closely linked with changes in air temperature whereas S. nutans was more sensitive to changes in water availability. Moreover, S. nutans was more responsive overall than A. gerardii to climate alterations. These results indicate both grass species are responsive to forecast changes in temperature and precipitation, but their differential sensitivity to temperature and water availability suggest that future population and community structure may vary based on the magnitude and scope of an altered climate.</p>10aAndropogon gerardii10aClimate variability10aLeaf gas exchange10aRaMPs10aSensitivity10aSorghastrum nutans1 aNippert, Jesse, B.1 aFay, P.A.1 aCarlisle, J.D.1 aKnapp, Alan, K.1 aSmith, M.D.  uhttps://www.sciencedirect.com/science/article/pii/S1146609X09000204?via%3Dihub02107nas a2200229   4500008004100000245008300041210006900124300001500193490000800208520135300216653002401569653002301593653001901616653001801635653001901653653002301672653001701695100001801712700002001730700001601750856011101766       2006                        eng d00aGrowth responses of twodominant C4 grass species to altered water availability0 aGrowth responses of twodominant C4 grass species to altered wate  a1001 -10100 v1673 aIdentifying key ecophysiological traits that differ among dominant plant species and can be linked to species‐specific responses to drought would improve our ability to forecast community and ecosystem responses to global climate change. The mesic grasslands of the central plains of North America are dominated by two C4 grass species, Andropogon gerardii and Sorghastrum nutans, which purportedly differ in their tolerance of water stress. Individuals of these two species were grown in the field under rain‐out shelters and subjected to wet (watered every 2–3 d) or dry (repeatedly subjected to wilting before watering) soil moisture regimes. A range of ecophysiological traits potentially important for tolerating water stress were concurrently measured. Although few traits differed between the species in the wet treatment, several traits were identified in the dry treatment that may enable A. gerardii to better tolerate drought. These were greater allocation to roots, reduced allocation to flowering, more rapid leaf turnover, and more rapid recovery of photosynthesis after wilting. The latter two traits may be particularly important for coping with increased variability in rainfall regimes in the future and are consistent with recently documented responses of A. gerardii to experimental increases in soil moisture variability.10aAndropogon gerardii10abiomass allocation10aClimate change10aleaf turnover10aphotosynthesis10aSorghastrum nutans10awater stress1 aSwemmer, A.M.1 aKnapp, Alan, K.1 aSmith, M.D.  uhttp://lter.konza.ksu.edu/content/growth-responses-twodominant-c4-grass-species-altered-water-availability01800nas a2200229   4500008004100000245004400041210004400085300001100129520114600140653002401286653001401310653001901324653001201343653001301355653001201368653003601380653002301416100002001439700001701459700001901476856007501495       2005                        eng d00aUsing local seed in prairie restoration0 aUsing local seed in prairie restoration  a22 -283 aChoice among local, non-local, and cultivar seeds for restoring native ecosystems is not purely an academic question—it also has practical consequences.In this article we summarize a series of genetic and competition studies of big bluestem (Andropogon gerardii Vitman. [Poaceae]), Indian grass (Sorghastrum nutans (L.) Nash. [Poaceae]), and purple prairie clover (Dalea purpurea Vent.[Fabaceae]) from remnant and restored Illinois (local) prairies, non-local remnant prairies, and 6 grass cultivars. We found genetic differences between local and non-local seed sources, that large populations do not necessarily have higher genetic diversity relative to small populations, and differences in plant performance could be related to seed source. Although obtaining large quantities of non-local and cultivar grass seeds may be affordable, available, and desirable given the amount of seeds required for prairie restoration, our research indicates genetic and plant performance differences between local and non-local seed sources in all 3 species. Such differences can affect both the short- and long-term success of restoration activities.10aAndropogon gerardii10acultivars10aDalea purpurea10aEcotype10aFabaceae10aPoaceae10aremnant and restored grasslands10aSorghastrum nutans1 aGustafson, D.J.1 aGibson, D.J.1 aNickrent, D.L.  uhttp://lter.konza.ksu.edu/content/using-local-seed-prairie-restoration03640nas a2200229   4500008004100000245007900041210006900120300001500189490000700204520289000211653002503101653002003126653002403146653001003170653001203180653002203192653002303214653002203237100002203259700001903281856011003300       2002                        eng d00aVariation in grazing tolerance among three tallgrass prairie plant species0 aVariation in grazing tolerance among three tallgrass prairie pla  a1634 -16430 v893 aThree tallgrass prairie plant species, two common perennial forbs (Artemisia ludoviciana and Aster ericoides [Asteraceae]) and a dominant C4 perennial grass (Sorghastrum nutans) were studied under field and greenhouse conditions to evaluate interspecific variation in grazing tolerance (compensatory growth capacity). Adaptation to ungulate grazing was also assessed by comparing defoliation responses of plants from populations with a 25-yr history of no grazing or moderate ungulate grazing. Under field conditions, all three species showed significant reductions in shoot relative growth rates (RGR), biomass, and reproduction with defoliation. In the two forbs, clipping resulted in negative shoot RGR and reductions in both number and length of shoot branches per ramet. Sorghastrum nutans maintained positive RGR under defoliation due to a compensatory increase in leaf production. Defoliation reduced rhizome production in A. ericoides and S. nutans, but not in A. ludoviciana. Clipping significantly reduced sexual reproductive allocation in all three species, although S. nutans showed a smaller reduction than the forbs. All three species showed similar responses to defoliation in burned and unburned sites. Under greenhouse conditions, a similar clipping regimen resulted in smaller reductions in growth and reproduction than those observed in the field. For all three species, the grazing tolerance indices calculated under natural field conditions were significantly lower than those estimated from greenhouse-grown plants, and the interspecific patterns of grazing tolerance were different. Aster ericoides exhibited the highest overall defoliation tolerance under greenhouse conditions, followed by S. nutans. Artemisia ludoviciana, the only study species that is typically not grazed by ungulates in the field, showed the lowest grazing tolerance. In the field experiment S. nutans showed the highest grazing tolerance and the two forbs had similar low tolerance indices. These patterns indicate that, despite high compensatory growth potential, limited resource availability and competition in the field significantly reduce the degree of compensation and alter interspecific differences in grazing tolerance among prairie plants. In all three species, defoliation suppressed sexual reproduction more than growth or vegetative reproduction. Significant interactions between plant responses to defoliation and site of origin (historically grazed or ungrazed sites) for some response variables (root/shoot ratios, rhizome bud initiation, and reproductive allocation) indicated some degree of population differentiation and genetic adaptation in response to a relatively short history of ungulate grazing pressure. The results of this study indicate that patterns of grazing tolerance in tallgrass prairie are both genetically based and also environmentally dependent.
10aAmbrosia ludoviciana10aAster ericoides10acompensatory growth10aforbs10aGrasses10agrazing tolerance10aSorghastrum nutans10atallgrass prairie1 aDamhoureyeh, S.A.1 aHartnett, D.C.  uhttp://lter.konza.ksu.edu/content/variation-grazing-tolerance-among-three-tallgrass-prairie-plant-species