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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
781

EVALUATING EXOTIC SPECIES ASSEMBLAGES ACROSS A CHRONOSEQUENCE OF RESTORED FLOODPLAIN FORESTS

McLane, Craig Russell 01 December 2009 (has links)
Exotic plant species pose a great risk to restoration success in post-agricultural bottomlands, but little information exists on their dynamics during early succession of actively restored sites. Compositional trends of exotic plants may be similar to those published for natives in other systems, with an early peak in herbaceous richness followed by a decline as woody species establish. I established 16 sites in an 18-year chronosequence (1991-2008) of restored forests, with an additional four mature sites for comparison, within the Cypress Creek NWR, Illinois. Within each site, I identified all vascular plant species and quantified soil texture, total soil C, total soil N, and canopy openness at three strata (1.5m, 1.25m, & 0.75m). Trends in exotic assemblages were significantly correlated with canopy openness at all strata (all p < 0.0001). Richness of exotic herbaceous species and native herbaceous species were related to stand age consistent with a non-linear Weibull regression model (R2 = 0.543, p = 0.005; R2 = 0.483, p = 0.013, respectively). Average percent herbaceous species cover also showed a similar reduction in overall abundance for both native and exotic plants but followed an exponential decay model (R2 = 0.3777, p = 0.0039; R2 = 0.3003, p = 0.0124, respectively). Woody native richness over time conformed to a logistic model (R2 = 0.404, p = 0.012). Woody exotic plants exhibited no discernible relationship with stand age, although they were in sites of all ages. My results indicate that herbaceous exotic species exhibit successional trends similar to natives and therefore may not pose a lasting threat to restoration projects in these floodplain forests. In contrast, woody exotic species can establish earlier or later in succession, persist under closed canopy conditions, and may pose a lasting threat. Thus, bottomland restorations and mature forests are quite vulnerable to exotic plants even after canopy closure.
782

The competitive response of Panicum virgatum cultivars to non-native invasive species in southern Illinois

Schwartz, Lauren Michele 01 December 2011 (has links)
Historically, the tallgrass prairie (TGP) was the largest ecosystem in North America, but today only about 10-15% of the original extent exists today. Some areas have experienced more extreme loss, for example in the state of Illinois less than 0.01% of high-quality native tallgrass prairie remains. Non-native invasive species are a recent phenomenon that threatens the integrity of surviving TGP communities. Ecotypes of dominant C4 grasses are the basis of numerous cultivars, many of which are utilized in prairie restorations. In this study, the effects of three invasive species (Bromus inermis, Schedonorus phoenix, and Poa pratensis) on two lowland (`Alamo' and `Kanlow') and three upland (`Blackwell', `Cave in Rock', and `Trailblazer') cultivars of the dominant C4 grass Panicum virgatum were tested. Two simple pair-wise greenhouse experiments were established in which cultivars were sown as a monoculture or as a mixture of the cultivars with one of three invasive species. Pots were subjected to one of two water treatments with three replicates of each treatment combination. Response variables (height, number of leaves, tiller density, and biomass) and resources (soil moisture, soil pH, soil electrical conductivity, and light intensity) were measured. The greenhouse studies showed that response variables were affected by the presence of invasive species and that the time of growth affected resource levels. Resources are allocated to different areas (i.e growth and reproduction) when competition and stress are implemented on the dominant species. This study was the first to experimentally test for the presence of the physiological stress marker, trigonelline, in a prairie grass. Trigonelline was highest in upland cultivars under low moisture and highest in lowland cultivars under low moisture treatments. The results of these greenhouse studies suggest that invasive species may differentially affect cultivars of Panicum virgatum that may be sown in a prairie restoration. Performance of the P. virgatum cultivars was dependent on the timing of growth, the pot size, the invasive species, as well as soil moisture level. Therefore, when choosing a cultivar source for restoration, resources (i.e. soil moisture) should be looked into to maximize the output of the cultivar.
783

Repaint, reframe, renew: updating sacred images during the early Italian Renaissance

Barahal, Susan 08 December 2016 (has links)
Several early Italian Renaissance sacred images underwent significant restorations shortly after their completion, despite the fact that the paintings had suffered no apparent damage. Paintings that were completed in the mid-to-late 1200s were restored only 30-40 years later. This dissertation explores the motivation behind the premature restorations of these intact and newly-created sacred images. As religious artworks, these objects were expected to move their viewers spiritually and to work as devotional intermediaries between the viewer and the sacred figures represented in the image. Some scholars contend that these paintings were prematurely restored in an effort to align the images with contemporary conceptions of style. Based on a scholarly analysis of historical and analytical literature, and close examination of the objects, this dissertation asserts a more compelling and nuanced motive for the restoration of these sacred images: these restorations were prompted by a desire to increase their spiritual efficacy by forging an empathic connection with viewers. The selective restorations primarily focused on repainting the faces and hands of important figures, with little or no repainting devoted to drapery, background or supporting figures. Repainting figures’ faces and hands enabled viewers to connect emotionally with these painted intermediaries and to create a greater empathic bond. I examine the motivation for artists to restore images prematurely and selectively within several contextual frameworks: the impact of viewers’ empathic connection with images is rooted in art historical and rhetorical theory and supported by current brain research; the appeal of early Italian Renaissance vernacular culture created a receptive environment for empathic connections to literature, poetry, devotional music and imagery; and early art historical writings on empathy. Chapter One examines the history of early Italian Renaissance restoration practices. Chapter Two explores how the art of Duccio di Buoninsegna and Giotto di Bondone motivated the selective repainting of devotional images. Chapters Three and Four present case studies of early Italian Renaissance sacred images that were prematurely repainted and reframed. Specific works examined include Coppo di Marcovaldo’s Madonna del Bordone, 1261, Guido da Siena’s Maestà, ca. 1270, and Taddeo Gaddi’s Madonna and Child with Four Saints, ca. 1340-45.
784

Gain-of-function and dominant-negative effects of distinct p53 mutations in lung tumours

Turrell, Frances Kathryn January 2018 (has links)
Lung cancer is the most common cause of cancer-related mortality worldwide with current treatments providing limited therapeutic benefit in most cases. TP53 (Trp53, p53) mutations occur in approximately 50% of lung adenocarcinoma cases and are associated with poor prognosis and so novel therapies that target these p53 mutant lung tumours are urgently needed. Despite the high frequency of p53 mutations in lung tumours, the impact these mutations have on response to therapy remains unclear in this cancer type. The aim of my project is to characterise the gain-of-function and dominant-negative effects of p53 mutations in lung tumours and to identify ways of therapeutically targeting these p53 mutant tumours based on dependencies and susceptibilities that our analysis uncovers. To characterise the gain-of-function and dominant-negative effects of p53 mutations I compared p53 mutant murine lung tumour cells that endogenously express either a contact (R270H, equivalent to R273H in humans) or conformational (R172H, equivalent to R175H in humans) p53 mutant protein and p53 null lung tumour cell lines; both in the presence and absence of wild-type p53. Interestingly, transcriptional and functional analysis uncovered metabolic gain-of-functions that are specific to the type of p53 mutation. Upregulation of mevalonate pathway expression was observed only in R270H lung tumours and consequently R172H and R270H lung tumours displayed distinct sensitivities to simvastatin, a mevalonate pathway inhibitor widely used in the clinic. Furthermore, the transcriptional signature underlying this sensitivity to simvastatin was also present in human lung tumours with contact p53 mutations, indicating that these findings may be clinically relevant. On the other hand, our analysis of the potential dominant-negative effects of the p53 mutants on wild-type p53 demonstrated that wild-type p53 was able to induce typical p53 target genes to a similar level in p53 null and mutant cells. Furthermore, wild-type p53 restoration resulted in comparable tumour suppressive responses in p53 mutant and null tumours and thus, p53-restoration therapy will likely be of benefit to patients with p53 mutations in lung cancer. Hence, I have demonstrated that lung tumours harbouring contact and conformational p53 mutations display common and distinct therapeutic susceptibilities.
785

Ecology of endangered damselfly \kur{Coenagrion ornatum} in post-mining streams in relation to their restoration

TICHÁNEK, Filip January 2016 (has links)
The thesis explores various aspects of ecology of endangered damselfly Coenagrion ornatum, the specialists for lowland headwaters, in post-mining streams of Radovesicka spoil. The first part of thesis is manuscript which has been already submitted in Journal of Insect Conservation. In the first part, we focused on population estimate of the local population using capture-recapture method, and explored its habitat requirements across life stages and spatial scales. In the next part, I assess mobility of the focal species and reveals basic distribution patterns. Finally, the thesis suggest various implications for restoration of post-mining freshwaters and conservation of the studied species.
786

Avaliação clínica longitudinal de restaurações de uma resina composta bulk-fill em dentes posteriores / Longitudinal clinical evaluation of restorations of a bulk-fill composite on posterior teeth

Rodrigues, Roger Borges January 2016 (has links)
Objetivos: O objetivo deste ensaio clínico randomizado foi avaliar o comportamento de restaurações de resina composta bulk-fill em dentes posteriores (classes I e II). Metodologia: Dezessete pacientes que necessitavam de restaurações em pelo menos dois dentes posteriores foram selecionados para participar do estudo. As causas para indicação das restaurações foram: substituição de restauração deficiente de amálgama ou resina composta e/ou lesão de cárie. Em cada paciente foram realizadas duas restaurações. Randomicamente, uma cavidade foi restaurada com a resina nanohíbrida Esthet-X HD (grupo controle) e a outra restaurada com a resina Esthet-X HD associada à resina de baixa contração Surefil SDR Flow (grupo teste). Em ambos os grupos, um sistema adesivo convencional de dois passos (XP Bond) foi utilizado. Todos os pacientes receberam tratamento global para a atividade cariosa. Após um período de quatro anos, a qualidade das restaurações foi avaliada por 1 examinador previamente calibrado, através de uma modificação do método USPHS e através do método FDI. Os dados obtidos foram submetidos à análise estatística pelo teste não-paramétrico Mann-Whitney (p<0,05) e a concordância intra-observador avaliada através de teste Kappa. Resultados: No quarto ano de acompanhamento, 26 dentes (18 restaurações classe I e 8 classe II) foram avaliadas, e não foram observadas diferenças estatisticamente significantes entre as restaurações dos grupos controle e teste para os métodos de avaliação utilizados. Não houve falhas em nenhuma das restaurações ao longo do tempo. Conclusão: A qualidade das restaurações classe I e II com resina bulk-fill foi semelhante à das restaurações com resina nanohíbrida convencional. A técnica com resina bulk-fill mostrou bom desempenho clínico tão bom quanto a convencional durante os 4 anos de acompanhamento. / Objectives: The objective of this randomized clinical trial was to evaluate the behavior of bulk-fill composite restorations in posterior teeth (classes I and II). Methodology: Seventeen patients who required restorations on at least two posterior teeth were selected to participate in the study. The causes for indication of restorations were: replacement of deficient amalgam or composite resin restoration and/or caries lesion. In each patient, two restorations were performed. Randomly, one cavity was restored with Esthet-X HD nanohybrid composite (control group) and the other was restored with Esthet-X HD resin associated with the bulk-fill composite Surefil SDR Flow (test group). In both groups, a two-step total-etch adhesive system (XP Bond) was used. All patients received global treatment for carious activity. After a period of four years, the quality of the restorations was evaluated by a previously calibrated examiner, through a modification of the USPHS method and through the FDI method. The data were submitted to statistical analysis by the non-parametric Mann-Whitney test (p <0.05) and the intra-observer agreement was evaluated by Kappa test. Results: At the 4-year follow-up, 26 teeth (18 class I and 8 class II restorations) were evaluated, and no statistically significant differences between control and test groups were observed for both evaluation methods used. There were no failures in any of the restorations over time. Conclusion: The quality of class I and II restorations with bulk-fill resin was similar to that of conventional nanohybrid resin. The bulk-fill composite technique showed good clinical performance as well as the conventional one during the 4 years of follow-up.
787

When do propagules matter? The role of ecological filters and regeneration dynamics during community assembly in tallgrass prairie restorations

Willand, Jason 01 December 2014 (has links)
Ecological restoration aims to augment and steer the composition and contribution of propagules for community regeneration in degraded environments. Three studies were conducted to elucidate the role of regeneration dynamics and dominant species on community assembly during tallgrass prairie restoration. In the first study, patterns in the abundance, richness, and diversity of seed and bud banks were quantified across an 11-year chronosequence of restored prairies and in prairie remnants to elucidate the degree to which the germinable seed bank, emerged seedlings, belowground buds, and emerged ramets were related to community regeneration. There were no directional patterns in the abundance, richness, or diversity of the germinable seed bank across the chronosequence. Emerged seedling abundance of sown species decreased during restoration, whereas richness and diversity of all emerged seedlings and non-sown emerged seedling species decreased across the chronosequence. Conversely, abundance and richness of belowground buds increased with restoration age and belowground bud diversity of sown species increased across the chronosequence. Numbers of emerged ramets also increased across the chronosequence and was driven primarily by the number of graminoid ramets. There were no temporal changes in abundance and richness of sown and non-sown emerged ramets, but diversity of sown emerged ramets increased across the chronosequence. This study demonstrates that after initial seeding, plant community structure in restored prairies increasingly reflects the composition of the bud bank. In the second study, abundance and richness of ramets, emerged seedlings, seed rain, and the soil seed bank were measured in a restoration experiment consisting of a split plot design with population source of dominant grasses (cultivar vs. local ecotype) and sown subordinate species (three unique pools of non-dominant species) as the subplot factor, respectively. Different sown species pools were included to assess whether any observed differences in propagule abundance or richness between the dominant species sources was generalizable across varying interspecific interactions. Abundance of emerged ramets was similar between communities sown with cultivar and local ecotypes of the dominant grasses but differed among sown species pools in prairie restored with cultivars but not local ecotypes. Number of emerged seedlings also differed among species pools, but only in communities sown with local ecotypes of the dominant grasses. There was also higher seedling emergence in communities sown with local ecotypes relative to cultivars of the dominant grasses in one species pool. Richness of the seed rain was influenced by an interaction between dominant grass population source and sown species pool, resulting from (1) higher richness in prairie restored with local ecotypes than cultivars of the native grasses in one species pool and (2) differences in richness among species pools that occurred only in prairie restored with the local ecotype grass source. Abundance and richness of the seed bank was not affected dominant grass population source. This study addressed a poorly understood potential effect of using cultivars in ecological restoration, specifically on the abundance and supply of propagules for community assembly. These results suggest that if both local ecotype and cultivar sources are available for restoration, using local ecotypes could result in more seedling germination and richness in the seed rain. One of the central concepts of ecology is to understand the processes that influence species diversity, and how the resulting diversity affects ecosystem functioning. Diversity has been hypothesized to be responsible for long-term community stability, contrasted by the idea that dominant species regulate temporal stability (mass ratio hypothesis). In the third study, community metrics (total plant cover, forb cover, C4 grass cover, richness, and diversity) were measured in a restoration experiment consisting of a split plot design with sown dominant grasses (Andropogon gerardii, Schizachyrium scoparium, and Sorghastrum nutans) and subordinate species (three unique pools of non-dominant species) as the subplot factor, with treatment (control vs. suppression of dominant grasses) as the sub-subplot factor, respectively. Dominant grass suppression had little effect on forb cover, richness, and diversity, but influenced total and C4 grass cover. Propagule addition increased community richness and diversity in year of sowing and year after sowing, but contributed little to total cover. Dominant grass suppression had an effect on new species recruitment in one of two species pools, with suppression of all dominant grasses having the greatest influence on total cover and richness of new species. These results suggest that dominant species collectively are responsible for modulating stable species composition during community assembly and can act as a biotic filter to the recruitment of new species, but diverse subordinate species assemblages are more important for temporal stability.
788

Evaluating Stream and Wetland Restoration Success on Surface Mines in Southern Illinois

Borries, Blair 01 December 2013 (has links)
Wetlands and streams provide many ecosystem services, yet many of these services have been lost during the process of surface mining. It is often not practical to avoid wetlands and streams, and newer technologies such as large draglines have made it possible to mine through large perennial streams and their associated riparian wetland systems. Laws such as the Surface Mining Control and Reclamation Act and Clean Water Act require the restoration of these systems in approximately the same location and configuration as before mining, but do not address the long-term replacement of function. In Perry County, Illinois, three stream segments of Bonnie Creek, Galum Creek, and Pipestone Creek and their associated riparian wetland systems were among the largest ever restored following surface mining. The research objective was to determine whether or not function was restored in the three aforementioned streams and riparian wetlands following surface mining reclamation. Wetland soil properties, vegetation, and hydrology at study sites along Bonnie and Galum Creeks were compared to that of nearby natural wetlands and across a chronosequence of soil age. Water quality was assessed [alkalinity, chloride (Cl), fluoride (Fl), iron (Fe), manganese (Mn), zinc (Zn), nitrate (NO3), sulfate (SO4), total dissolved solids (TDS), and total suspended solids (TSS)] in the three restored streams for post restoration trends over time and along the length of the restored channels. Deep basins, called incline pits, were located inline of all three restored channels and are unique to streams restored on surface mines. Stream samples were collected above and below incline pits during storm events to evaluate their ability to reduce sediment concentrations. Two types of wetlands were found at the mine site: mined planned wetlands (MPWs) that had deeper water and fewer or no trees, and mined bottomland forested wetlands (MBFWs) with more shallow water depths and many trees. Significant differences were found between the two wetland types among soil properties, vegetation, and hydrology. Unlike most studies comparing wetlands restored on non-mined sites to natural wetlands, SOM, C, N, and C/N ratio in the surface 15 cm in the MBFWs were not significantly different from the natural wetlands, indicating restoration of function. Plant taxa richness was higher in both mined wetland types than in the natural wetlands at lower elevation sample points where inundation was seasonal. Overall, the mined wetlands also retained water within 30 cm of the surface for more time than the natural wetlands. However, not all function was fully regained in the mined wetlands. Several soil properties were significantly different in the mined wetlands compared to the natural wetlands. SOM, N and the C/N ratio was significantly lower in the 15-30 cm depth, and in the surface 15 cm of the lower elevation samples of the MPW. Soil texture was significantly different in the MPW. There was more sand and less silt. Plan taxa richness was also lower in the higher elevation sample points of the MPW due to the presence of the invasive Phragmites australis. Few trends were found in the soil properties across a chronosequence of soil age. Only pH showed a significant negative linear trend in both mined wetland types across soil age. Assessment of the water chemistry of the restored streams showed that for some parameters, water quality remained stable or improved with distance or time along the restored streams. However, along Bonnie and Galum Creek, a significant positive trend was seen by length of relocated channel in SO4, Fe, Mn, Zn, TDS, conductivity, and Cl. On the other hand, at Pipestone Creek, significant negative trends were evident in TDS, Mn, water temperature, conductivity, and SO4 levels over time or along the length of the relocated channel. Trends along the length of the Pipestone Creek were only found in monitoring conducted twenty years after the channel relocation was complete. Sediment concentration above and below the incline pits inline of Bonnie and Galum Creek were not significantly different based on the sampling of two storm events. An additional input from an agricultural drainage ditch to the Bonnie Pit increased sediment concentrations at the downstream sample point counteracting the reductions that were seen in the Galum pit. Research on the mined stream and riparian systems indicated that reclamation of wetlands and streams to a stable or condition similar to a natural system is possible and sets a standard for future mining operations to follow. However, several shortcomings were identified. Reduced levels of SOM and soil N in the MPWs in the surface 15 cm of the lower sample points may have been the result of longer periods of inundation that reduced nitrification and vegetation recruitment. SOM, soil N, and the C/N ratio in the 15-30 cm depth were lower in the mined wetlands suggesting that these properties take longer to recover at deeper depths, but the significant linear trend in pH show that soil in the deeper strata is changing with time. Invasion by P. Australis reduced taxa richness suggesting that invasive plants are still a problem even more than twenty years after restoration. In addition, the increase in conductivity and SO4 downstream of a visible seep in Bonnie Creek highlight the potential for contaminated groundwater to affect surface water. More consideration should be given to reclaiming not just the surface and subsoils, but also the deeper water bearing strata to ensure that surface water chemistry is not impacted by mining.
789

THE EFFECT OF COLLECTION AND ESTABLISHMENT SEASON, PLANTING ORIENTATION AND ATTACHED CULMS ON THE SURVIVAL AND GROWTH OF ARUNDINARIA GIGANTEA (WALT.) MUHL. (GIANT CANE) RHIZOME PROPAGULES

Brendecke, William Walter 01 January 2008 (has links)
Arundinaria gigantea (Walt.) Muhl. (giant cane) is a native North American bamboo. The mass assemblages of giant cane stems (culms) can form monotypic stands called "canebrakes" with historic distribution encompassing floodplains of the southeastern United States. Canebrake ecosystems have served as an important habitat for a variety of mammalian, avian, and reptilian species due in part by the protective nature the dense culms provide. Also, giant cane also can serve as an effective riparian zone buffer for the protection of water quality. Land conversion and altered disturbance regimes have reduced cane to 2% of historical accounts. Consistently, there is great interest in restoring canebrake ecosystems. However, canebrake restoration efforts face difficulties such as infrequent seeding and low viability, limited availability of seedlings or rhizome planting stock, and inefficient establishment and management techniques. To address these problems, two studies were designed to further develop giant cane propagation thereby aiding management efforts intended in restoring canebrake ecosystems. Study 1 (greenhouse) objective was to compare the survivability and growth responses of bare rhizomes and rhizomes with attached and trimmed culms with different planting orientation. Study design was a randomized complete block with approximately 20 rhizomes of each propagule type (bare rhizomes, rhizomes with culms trimmed to 3cm and rhizomes with culms trimmed to 20cm) planted in two orientations (buried flat or angled and partially exposed) in each of 4 benches (N=239). Propagule type and planting orientation were determined randomly. After six months, propagule survival was 86% and was independent of orientation (chi square 1df = 1.56, p=0.212) and propagule type (chi square 2df =3.88, p=3.88). There was an interaction between planting orientation and propagule type for the number of new rhizomes and culms, above ground biomass, but not for newly formed rhizome diameter or cumulative culm and rhizome length. Rhizome propagules with attached trimmed culms produced, on average, one more rhizome and were 71 cm longer than newly formed rhizomes from the bare rhizome propagules. Planting orientation had no effect on any measured character of long culmed propagules, burying the short-culmed or bare rhizomes tended to reduce growth responses. However, among exposed propagules, growth responses tended to be similar. Study 2 (field-scale) objective was to determine if genotype (3 collection sources) and collection season/ planting season (C/P) (fall/fall, fall/spring, spring/spring) affect survival and growth of giant cane. Study design was a randomized complete block design with between 12 and 20 bare rhizomes per each of 3 collection sources (subplots) planted in each of 3 rows (collection season/ planting season main plots) blocked 6 times across 2 sites (N=2086). Location of collection sources within subplots and C/P within plots were randomly chosen. Rhizomes were planted in rows using a tree planter. Mean survival of cane plants after one growing season was similar at each site with a mean of 11.1%. Survival was dependent on collection source and C/P seasons. Survival ranged from a high of 38.3% for the spring/spring planted Upper Cache River source to 0.4% for two of the other 9 treatment combinations. Collecting and planting rhizomes in the spring for two of the three collection sources produced the highest percent survival compared to stock collected in the fall then planted or stored until spring. These results suggest the importance of collection source, collection season, planting season, propagule morphology and orientation on the survival and new growth of giant cane in southern Illinois.
790

RESPONSE OF REGIONAL SOURCES OF TALLGRASS PRAIRIE SPECIES TO VARIATION IN CLIMATE AND SOIL MICROBIAL COMMUNITIES

Goad, Rachel Kathleen 01 August 2012 (has links)
Restoration of resilient plant communities in response to environmental degradation is a critical task, and a changing climate necessitates the introduction of plant communities adapted to anticipated future conditions. Ecotypes of dominant species can affect associated organisms as well as ecosystem function. The extent of ecotypic variation in dominant tallgrass prairie species and the consequences of this variation for ecosystem functioning were studied by manipulating two potential drivers of plant community dynamics: climate and the soil microbial community. Climate was manipulated indirectly through the use of reciprocal restorations across a rainfall gradient where regional sources of dominant grasses Andropogon gerardii and Sorghastrum nutans were seeded with 8 other native species that occur in tallgrass prairie. Four dominant grass sources (originating from central Kansas [CKS], eastern Kansas [EKS], southern Illinois [SIL], or a mixture of these) were reciprocally planted within four sites that occurred across a precipitation gradient in western KS (Colby, KS), CKS (Hays, KS), EKS (Manhattan, KS) and SIL (Carbondale, IL). The three grass sources and mixture of sources were sown into plots according to a randomized complete block design at each sites (n=16, 4 plots / block at each site). Aboveground net primary productivity (ANPP) was measured at the end of the 2010 and 2011 growing season at each site. In 2010, total ANPP declined from western to eastern Kansas, but increased across the geographic gradient in 2011. The dominant grasses did not comprise the majority of community ANPP in WKS, CKS or SIL in either year but did contribute most to total ANPP at the EKS site in 2011. In 2010, volunteer forbs comprised the largest proportion of ANPP in WKS, whereas and in both years planted forbs comprised the largest proportion of ANPP in SIL. Ecotypic variation in ANPP of A. gerardii was not evident, but Sorghastrum nutans ANPP exhibited a site by source effect in 2010 that did not suggest a home site advantage. Variation in the competitive environment at each site may have masked ecotypic variation during community assembly. Further, ANPP responses suggest that grasslands in early stages of establishment may respond more stochastically to climatic variation than established grasslands. Longer term studies will clarify whether ecotypes of dominant prairie grasses affect ecosystem function or community trajectories differently during restoration. Ecotypes of dominant species may support different soil microflora, potentially resulting in plant-soil feedback. A second experiment tested for local adaptation of prairie plant assemblages to their soil microbial community. Native plant assemblages from Kansas and Illinois were tested for local adaptation to their `home' soil by reciprocally crossing soil and plant source in a greenhouse experiment. Seeds and soil were obtained from two remnant prairies, one in eastern Kansas and one in central Illinois, with similar species composition but differing climate. Seeds of four species (Andropogon gerardii, Elymus canadensis, Lespedeza capitata, Oligoneuron rigidum) common to both locations were collected, germinated, and transferred to pots to create 4-species assemblages from each region. Non-prairie (NP) soil from the edge of an Illinois agricultural field was also included as an inoculum treatment to increase relevance to restoration. Kansas and Illinois plant assemblages were subjected to a fully factorial combination of soil inocula [with associated microbial communities] (3 sources: KS, IL, NP) and soil sterilization treatment (sterilized or live). Plants were harvested after 20 weeks and soil was analyzed for microbial composition using phospholipid fatty acid (PLFA) markers. Soil sources had different nutrient concentrations and sterilization resulted in a flush of NH4+, which complicated detection of soil microbial effects. However, plant sources did exhibit variation in productivity responses to soil sources, with Kansas plants more responsive to live soil sources than Illinois plants. Despite confounding variation in soil fertility, soil inoculation was successful at manipulating soil microbial communities, and plant sources responded differently to soil sources. Consideration of feedback between soil and plants may be a missing link in steering restoration trajectories.

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