02192nas a2200133 4500008004100000245010100041210006900142490001400211520169700225100002201922700001901944700001701963856007801980 2014 eng d00aBelowground bud banks of tallgrass prairie are insensitive to multi-year, growing-season drought0 aBelowground bud banks of tallgrass prairie are insensitive to mu0 v5: art1033 a

In tallgrass prairie plant communities, new shoots are recruited from belowground bud banks, often in response to disturbance. We explored the contribution of belowground bud banks to grassland stability when perturbed by severe drought. We sought to quantify changes in bud bank density and demography, assess the contribution of the bud bank to aboveground net primary productivity, and compare shifts in above- and belowground plant community structure in response to drought. We experimentally reduced precipitation 76% from ambient levels for two years, and compared responses of drought plots to ambient and irrigated controls during the two years of drought and two years of recovery. We measured belowground bud bank density and aboveground shoot density, canopy cover, and aboveground net primary productivity. While aboveground net primary productivity and C4 grass flowering shoot density declined during drought, bud bank density was insensitive to drought. Rapid resilience of the aboveground plant community following cessation of drought appears to be mediated by the resistance of bud banks to drought. Shoot density, but not bud bank density, was positively correlated with total aboveground net primary productivity. Furthermore, proportional reductions in aboveground net primary productivity increased as shoot density increased. Plant community structure shifted both above- and belowground in response to precipitation treatments. Our results suggest that the response of perennial grasslands to drought may be mediated by the stable belowground bud bank, with shifts in abundance of individual species maintaining overall bud bank density and ecosystem function.

1 aVanderWeide, B.L.1 aHartnett, D.C.1 aCarter, D.L. uhttps://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/ES14-00058.103310nas a2200193 4500008004100000245009900041210006900140260004300209490002200252520267700274653001902951653001902970653001802989653002103007653001403028100001703042700002003059856003703079 2013 eng d00aGrassland restoration in a changing world: consequences of practices and variable environments0 aGrassland restoration in a changing world consequences of practi aManhattan, KSbKansas State University0 vPhD. Dissertation3 a

The feasibility of restoration, which traditionally targets historical conditions, is questionable in the context of global change. To address this, my dissertation investigated (Chapter 2) the patterns of restoration establishment along a chronosequence of restored prairies with respect to nearby remnant prairies, (Chapters 3-4) responses of plant communities in restorations initiated using different methods (levels of species richness and sowing density) to drought, which is projected to increase in frequency, and (Chapters 5-6) the effects of propagule source and variation (mixing among sources) on restoration establishment and the generality of restoration outcomes across variable environments using reciprocal common gardens of multi-species restoration seedings. Chapter 2, published in Restoration Ecology, showed that restoration led to the recovery of desirable characteristics within several years, but restorations utilizing primarily fall-collected seeds likely diminished the representation of early phenology species, so biodiversity may be further enhanced by including early phenology species in seeding mixes. Chapters 3 and 4, published respectively in Ecological Applications and Applied Vegetation Science, examined the establishment of native plant communities after seeding and their responses to experimentally imposed drought. Both high seed mixture richness and high density seeding resulted in greater establishment of native, seeded species compared to low richness and low density treatments, and exotic species were less prevalent in high richness and high density treatments. However, we found little evidence of differential drought resistance, recovery, and resilience among treatments. This result coupled with increases in exotic species following drought suggest that other forms of active management may be needed to produce restored plant communities that are robust to climate change. Chapter 5 (published in Ecosphere) and Chapter 6 found that seed source affects individual species establishment, community structure, and productivity. However, there was no consistent advantage for any source, including local sources, across sites or species. This suggests that source effects on single species or effects observed at single locations should not be broadly generalized. Together, this dissertation shows that restoration can recover many characteristics of native prairies and that manipulation of seeding practices (seed mixture richness, seeding density, seed source) influence grassland establishment in terms of productivity, community structure, invasion, and the abundance and survival of individual species.

10achronosequence10aClimate change10acommon garden10alocal adaptation10atallgrass1 aCarter, D.L.1 aBlair, John, M. uhttp://hdl.handle.net/2097/1535703012nas a2200265 4500008004100000245011300041210006900154300000900223490000600232520219900238653001802437653002402455653001402479653002202493653002102515653002802536653001702564653001502581653001602596653002302612653001402635100001702649700002002666856006002686 2013 eng d00aSeed source has variable effects on species, communities, and ecosystem properties in grassland restorations0 aSeed source has variable effects on species communities and ecos a93 -0 v43 aResearch to date regarding the relative advantages of local versus non-local sources of plantmaterial for restoration has produced equivocal results. This research has typically focused on theperformance of individual species at individual locations and without addressing higher order communityand ecosystem properties. We investigated the effects of seed source (local, non-local, and mixed-sourcetreatments) on species, community, and ecosystem properties under a range of environmental conditionsusing reciprocal common gardens at locations in three states (Nebraska, Kansas, and Oklahoma). In orderto mimic the restoration of grassland vegetation under realistic conditions where multiple species interactwith one another during establishment, we seeded twelve species together between December, 2009 andJanuary, 2010, and assessed responses in 2010, 2011, and 2012. Both common garden location and seedsource affected the establishment of individual species (measured as species-specific biomass), butresponses were not consistent among species. No seed source had a consistent advantage across all sites oracross all species. In a few cases, the local source was most productive for a particular species at onelocation, but no species showed a consistent local advantage across locations or years. Rather, in two out ofthree species that exhibited a local advantage at one location, the same source was also the most productiveat a non-local site. Community structure and species richness differed among locations in all years, butsource did not significantly affect seeded species richness, and source only affected community structure in2011. Despite source effects on individual species and community structure, seed source had no significanteffects on the combined productivity of seeded species. These results do not support the targeted use oflocal sources when the establishment of sown species and primary productivity are restoration objectives.Using mixed-source species mixtures may increase chances of restoration success, given the idiosyncrasy ofindividual species’ responses among locations and potential site-specific environmental changes likely tooccur in the future.10acommon garden10acommunity structure10adispersal10agenetic diversity10alocal adaptation10amanaged relocationplant10aproductivity10aprovenance10arestoration10aseed transfer zone10atallgrass1 aCarter, D.L.1 aBlair, John, M. uhttp://www.esajournals.org/doi/pdf/10.1890/ES13-00090.102048nas a2200265 4500008004100000245007800041210006900119300001300188490000700201520130200208653001701510653001901527653001401546653000901560653001001569653000801579653001301587653001001600653001201610653002601622100001701648700002001665700002001685856007701705 2012 eng d00aDrought-mediated stem and belowground bud dynamics in restored grasslands0 aDroughtmediated stem and belowground bud dynamics in restored gr a470 -4780 v153 a

Question Does the below-ground bud bank mediate response to drought in restored grasslands? Location Platte River Valley region of south-central Nebraska, USA. Methods We imposed severe drought for one growing season using rainfall manipulation structures and measured the response of above- and below-ground plant communities (ramet and below-ground bud densities) with respect to non-drought controls during the drought year and a recovery year. Results Drought reduced below-ground bud bank density and above-ground stem density. However, bud bank density recovered, and bud production was higher on previously droughted subplots relative to controls in the year following drought. The response of below-ground bud and above-ground stem density to drought differed according to functional identity (C3 grass, C4 grass, and forb), with forbs least resistant to, but having the greatest recovery from, drought. Conclusions While overall density in restored grasslands was resilient, drought effects on below-ground bud banks may have longer-term impacts on plant community structure. Reduced density above- or below-ground during the growing season following drought may allow for the persistence of species relatively more reliant on recruitment from seed banks in favourable micro-sites.

10aBelow-ground10aClimate change10aCommunity10aforb10agrass10aLag10aMeristem10aplant10aprairie10aRainfall manipulation1 aCarter, D.L.1 aVanderweide, B.1 aBlair, John, M. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1654-109X.2012.01200.x02622nas a2200133 4500008004100000245012400041210006900165300001500234490000700249520212100256100001702377700002002394856007402414 2012 eng d00aHigh richness and dense seeding enhance grassland restoration establishment, but have little effect on drought response0 aHigh richness and dense seeding enhance grassland restoration es a1308 -13190 v223 a

Restorations commonly utilize seed addition to formerly arable lands where the development of native plant communities is severely dispersal limited. However, variation in seed addition practices may profoundly affect restoration outcomes. Theory and observations predict that species-rich seed mixtures and seeding at high densities should enhance native plant community establishment, minimize exotic species cover, and may promote resistance and resilience to, and recovery from, environmental perturbations. We studied the post-seeding establishment of native plant communities in large grassland restoration plots, which were sown at two densities crossed with two levels of species richness on formerly arable land in Nebraska, USA, and their responses to drought. To evaluate drought resistance, recovery, and resilience of restored plant communities, we erected rainfall manipulation structures and tracked the response of seeded species cover and total plant biomass during experimental drought relative to controls and in the post-drought growing season. High seed richness and high-density seeding treatments resulted in greater richness and cover of native, seeded species per 0.5 m2 compared to low-richness and low-density treatments. Cover differences in response to seed mixture richness were driven by native forbs. Richness and cover of exotic species were lowest in high-richness and high-density treatments. We found little evidence of differential drought resistance, recovery, and resilience among seeding treatments. Increases in exotic species across years were restricted to drought subplots, and were not affected by seeding treatments. Grassland restoration was generally enhanced and exotic cover reduced both by the use of high-richness seed mixtures and high-density seeding. Given the lack of restoration treatment effects on the resistance, recovery, or resilience of seeded species exposed to drought, and the increases in exotic species following drought, other forms of active management may be needed to produce restored plant communities that are robust to climate change.

1 aCarter, D.L.1 aBlair, John, M. uhttps://esajournals.onlinelibrary.wiley.com/doi/abs/10.1890/11-1970.102396nas a2200205 4500008004100000245013800041210006900179300001300248490000700261520172700268653001401995653001302009653001102022653001402033653001502047653001402062100001702076700002002093856007702113 2012 eng d00aRecovery of native plant community characteristics on a chronosequence of restored prairies seeded into pastures in West-Central Iowa0 aRecovery of native plant community characteristics on a chronose a170 -1790 v203 a

Restored grasslands comprise an ever-increasing proportion of grasslands in North America and elsewhere. However, floristic studies of restored grasslands indicate that our ability to restore plant communities is limited. Our goal was to assess the effectiveness of restoration seeding for recovery of key plant community components on former exotic, cool-season pastures using a chronosequence of six restoration sites and three nearby remnant tallgrass prairie sites in West-Central Iowa. We assessed trends in Simpson's diversity and evenness, richness and abundance of selected native and exotic plant guilds, and mean coefficient of conservatism (mean C). Simpson's diversity and evenness and perennial invasive species abundance all declined with restoration site age. As a group, restoration sites had greater richness of native C3 species with late phenology, but lower richness and abundance of species with early phenology relative to remnant sites. Total native richness, total native abundance (cover), mean C, and abundance of late phenology C3 plants were similar between restoration and remnant sites. Observed declines in diversity and evenness with restoration age reflect increases in C4 grass abundance rather than absolute decreases in the abundance of perennial C3 species. In contrast to other studies, restoration seeding appears to have led to successful establishment of tallgrass prairie species that were likely to be included in seeding mixtures. While several floristic measures indicate convergence of restoration and remnant sites, biodiversity may be further enhanced by including early phenology species in seeding mixes in proportion to their abundance on remnant prairies.

10agrassland10aInvasive10amean C10aphenology10asuccession10atallgrass1 aCarter, D.L.1 aBlair, John, M. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1526-100X.2010.00760.x02195nas a2200133 4500008004100000245011500041210006900156300001000225490000600235520170500241100001701946700002001963856007801983 2012 eng d00aSeed source affects establishment and survival for three grassland species sown into reciprocal common gardens0 aSeed source affects establishment and survival for three grassla a102 -0 v33 a

The source of plant material can affect the successful establishment and subsequent survival of plant species in restoration. Sometimes a local advantage is assumed or advocated, but research to date is equivocal on the relative success of local versus non-local plant sources in restoration. Global change, which is altering environmental conditions broadly and within local sites, raises additional questions regarding whether local sources will consistently perform best in the future. We investigated the effects of seed source (local vs. non-local) on the performance of three grassland species across variable environments using reciprocal common gardens in three states (Nebraska, Kansas, and Oklahoma). In order to mimic the restoration of grassland vegetation from seed under realistic conditions where species interact with one-another during establishment, we focused on three species (Elymus canadensis, Oligoneuron rigidum, and Sorghastrum nutans) that were seeded together into communities with nine additional grassland species, simultaneously and identically manipulating source for all species. Both common garden site and seed source affected initial (first year) establishment in terms of density and survival, but responses differed among seed sources and were not consistent among species. No seed source, including local, had a consistent advantage. Effects of seed source on initial density, in addition to survival, suggest that experiments utilizing transplants might miss important effects of seed source on establishment and that the relative performance of different sources within a single site or that of any one species across sites cannot be easily generalized.

1 aCarter, D.L.1 aBlair, John, M. uhttps://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/ES12-00223.1