%0 Journal Article %J Proceedings of the National Academy of Sciences %D 2017 %T Different clades and traits yield similar grassland functional responses %A Forrestel, Elisabeth J. %A M.J. Donoghue %A Edwards, Erika J. %A Jetz, Walter %A du Toit, Justin C. O. %A M.D. Smith %K biogeography %K Ecosystem function %K Functional traits %K grasslands. phylogenetics %X Plant functional traits are viewed as key to predicting important ecosystem and community properties across resource gradients within and among biogeographic regions. Vegetation dynamics and ecosystem processes, such as aboveground net primary productivity (ANPP), are increasingly being modeled as a function of the quantitative traits of species, which are used as proxies for photosynthetic rates and nutrient and water-use efficiency. These approaches rely on an assumption that a certain trait value consistently confers a specific function or response under given environmental conditions. Here, we provide a critical test of this idea and evaluate whether the functional traits that drive the well-known relationship between precipitation and ANPP differ between systems with distinct biogeographic histories and species assemblages. Specifically, we compared grasslands spanning a broad precipitation gradient (∼200–1,000 mm/y) in North America and South Africa that differ in the relative representation and abundance of grass phylogenetic lineages. We found no significant difference between the regions in the positive relationship between annual precipitation and ANPP, yet the trait values underlying this relationship differed dramatically. Our results challenge the trait-based approach to predicting ecosystem function by demonstrating that different combinations of functional traits can act to maximize ANPP in a given environmental setting. Further, we show the importance of incorporating biogeographic and phylogenetic history in predicting community and ecosystem properties using traits. %B Proceedings of the National Academy of Sciences %V 114 %P 705 - 710 %G eng %U https://www.pnas.org/content/114/4/705 %N 4 %M KNZ001847 %R 10.1073/pnas.1612909114 %0 Journal Article %J Ecological Applications %D 2017 %T Restoration and management for plant diversity enhances the rate of belowground ecosystem recovery %A Klopf, Ryan P. %A S.G. Baer %A E.M. Bach %A Six, Johan %K Aggregates %K Biodiversity %K carbon %K Ecosystem function %K nitrogen %K phospholipid fatty acid %K prairie %K root %K soil %X

The positive relationship between plant diversity and ecosystem functioning has been criticized for its applicability at large scales and in less controlled environments that are relevant to land management. To inform this gap between ecological theory and application, we compared recovery rates of belowground properties using two chronosequences consisting of continuously cultivated and independently restored fields with contrasting diversity management strategies: grasslands restored with high plant richness and managed for diversity with frequent burning (n = 20) and grasslands restored with fewer species that were infrequently burned (n = 15). Restoration and management for plant diversity resulted in 250% higher plant richness. Greater recovery of roots and more predictable recovery of the active microbial biomass across the high diversity management strategy chronosequence corresponded with faster recovery of soil structure. The high diversity grasslands also had greater nutrient conservation indicated by lower available inorganic nitrogen. Thus, mesic grasslands restored with more species and managed for high plant diversity with frequent burning enhances the rate of belowground ecosystem recovery from long-term disturbance at a scale relevant to conservation practices on the landscape

%B Ecological Applications %V 27 %P 355 - 362 %G eng %U https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/eap.1503 %N 2 %M KNZ001819 %R 10.1002/eap.1503 %0 Journal Article %J Plant Ecology %D 2012 %T Measuring genetic diversity in ecological studies %A M.L. Avolio %A Beaulieu, J. %A Lo, E. %A M.D. Smith %K Community diversity %K Ecosystem function %K Genome diversity %K Phenotype %K SGDC %X

There is an increasing interest in how genetic diversity may correlate with and influence community and ecosystem properties. Genetic diversity can be defined in multiple ways, and currently lacking in ecology is a consensus on how to measure genetic diversity. Here, we examine two broad classes of genetic diversity: genotype-based and genome-based measures. Genotype-based measures, such as genotypic richness, are more commonly used in ecological studies, and often it is assumed that as genotypic diversity increases, genomic diversity (the number of genetic polymorphisms and/or genomic dissimilarity among individuals) also increases. However, this assumption is rarely assessed. We tested this assumption by investigating correlations between genotype- and genome-based measures of diversity using two plant population genetic datasets: one observational with data collected at Konza Prairie, KS, and the other based on simulated populations with five levels of genotypic richness, a typical design of genetic diversity experiments. We found conflicting results for both datasets; we found a mismatch between genotypic and genomic diversity measures for the field data, but not the simulated data. Last, we tested the consequences of this mismatch and found that correlations between genetic diversity and community/ecosystem properties depended on metric used. Ultimately, we argue that genome-based measures should be included in future studies alongside genotypic-based measures because they capture a greater spectrum of genetic differences among individuals.

%B Plant Ecology %V 213 %P 1105 -1115 %G eng %U https://link.springer.com/article/10.1007%2Fs11258-012-0069-6 %M KNZ001481 %R 10.1007/s11258-012-0069-6 %0 Journal Article %J Journal of the North American Benthological Society %D 2011 %T Direct and indirect effects of central stoneroller (Campostoma anomalum) on mesocosm recovery following a flood: can macroconsumers affect denitrification? %A Reisinger, A.J. %A Presuma, D.L. %A K. B. Gido %A W. K. Dodds %K Campostoma %K denitrification %K Ecosystem function %K Flood %K grazer %K mesocosm %K prairie streams %K recovery %X

Anthropogenic N loadings and perturbations of macroconsumer communities impair ecological and economic services provided by streams. Organisms are adapted to natural disturbances, such as flooding and desiccation, but how anthropogenic and natural disturbances interact is poorly understood. We used large outdoor mesocosms to study the effect of Campostoma anomalum, a common prairie headwater-stream minnow, and NH4+ additions (to simulate fish excretion) on the recovery of ecosystem structure and function following a flood, highlighting the potential for Campostoma (and other macroconsumers) to affect denitrification. Campostoma and NH4+ treatments differentially affected particulate organic matter size and filamentous algal structure. Ecosystem structure responded differently to mesocosm treatment over time, a result suggesting that grazers or NH4+-N availability may be especially important during early recovery periods. The presence of Campostoma did not influence denitrification, but NH4+ additions altered the response of denitrifiers to nutrient and energy amendments, and denitrification rates decreased following the recovery of mesocosms. Temporal changes in denitrification probably were caused by increasing hyporheic dissolved O2 concentrations, which led to potentially fewer anoxic microsites for production of denitrification enzymes. Our study shows that grazers affect the recovery of ecosystem structure, but denitrification in the context of these prairie-stream mesocosms appears to be unaffected by Campostoma.

%B Journal of the North American Benthological Society %V 30 %P 840 -852 %G eng %U https://www.journals.uchicago.edu/doi/10.1899/10-169.1 %M KNZ001434 %R 10.1899/10-169.1 %0 Thesis %D 2007 %T Fishes and floods: stream ecosystem drivers in the Great Plains %A Bertrand, K.N. %K Biodiversitym %K Ecosystem function %K Flood frequency %K Grazing minnow %K Omnivorous minnow %K Prairie stream %X

Global climate change could lead to less frequent but more severe precipitation events in the Great Plains, altering the hydrologic regimes of streams. It is important to quantify species roles in these dynamic systems, because changes in stream communities are likely to accompany predicted changes in hydrology. The effects of species on ecosystem processes also are limited by the frequency of disturbance, because prairie streams are harsh, nonequilibrium systems characterized by a wide range of disturbances. In particular, frequent floods that reset the ecosystem to an early successional state can override the influence of consumer populations because the availability of resources is too unpredictable to maintain stable populations of those species or because species are absent following the flood. As flood frequency decreases, potential consumer effects may intensify. Using a combination of field and experimental stream mesocosm experiments, I (1) characterized the ecosystem effects of southern redbelly dace (Phoxinus erythrogaster), a grazing minnow, (2) tested the interactive effects of flood frequency and the presence of water column (red shiner; Cyprinella lutrensis) or grazing minnows (Phoxinus) on ecosystem processes, and (3) tested the effects of species loss from the grazer functional feeding group on stream ecosystem structure and function. I found that dace affected some aspects of ecosystem structure but not function, which suggested that grazer effects in prairie streams may not be consistent across taxa. In the context of flood frequency, both the water column omnivore and dace affected recovery of prairie stream primary producers following flooding disturbance by stimulating production, presumably through nutrient remineralization. However, some of these effects were transient or dependent on flood frequency, and my results indicate that consumer effects depend not only on environmental venue but also on the balance between consumptive losses and nutrient stimulation. In a comparison of the effects of removing different taxa from a grazer assemblage, the loss of crayfish, snails, or dace from a grazer assemblage did not differentially affect ecosystem processes, suggesting overlap in the ecosystem roles of these species in the context of this experiment.

%I Kansas State University %C Manhattan, KS %V PhD Dissertation %P 1 -141 %G eng %U http://hdl.handle.net/2097/297 %9 Ph.D. Thesis %M KNZ001103