02500nas a2200193 4500008004100000245012200041210006900163300001300232490000800245520183900253653001902092653001302111653003002124653001502154653002702169100002802196700001602224856006602240 2016 eng d00aSoil nutrient additions increase invertebrate herbivore abundances, but not herbivory, across three grassland systems0 aSoil nutrient additions increase invertebrate herbivore abundanc a485 -4970 v1803 a
Resource availability may influence invertebrate communities, with important consequences for ecosystem function, such as biomass production. We assessed: (1) the effects of experimental soil nutrient additions on invertebrate abundances and feeding rates and (2) the resultant changes in the effects of invertebrates on aboveground plant biomass at three grassland sites spanning the North American Central Plains, across which plant tissue chemistry and biomass vary. Invertebrate communities and rates of herbivory were sampled within a long-term nutrient-addition experiment established at each site along the broad Central Plains precipitation gradient. Additionally, the effects of invertebrates on aboveground plant biomass were determined under ambient and elevated nutrient conditions. At the more mesic sites, invertebrate herbivore abundances increased and their per capita rate of herbivory decreased with nutrient additions. In contrast, at the semi-arid site where plant biomass is low and plant nutrient concentrations are high, invertebrate herbivore abundances did not vary and per capita rates of herbivory increased with nutrient additions. No change in the effect of invertebrate herbivores on aboveground plant biomass was observed at any of the sites. In sum, nutrient additions induced shifts in both plant biomass and leaf nutrient content, which altered invertebrate abundances and feeding rate. However, due to the inverse relationship between changes in herbivore abundance and per capita rates of herbivory, nutrient additions did not alter the effect of invertebrates on aboveground biomass. Overall, we suggest that this inverse response of herbivore abundance and per capita feeding rate may buffer ecosystems against changes in invertebrate damage in response to fluctuations in nutrient levels.
10aCentral Plains10anitrogen10aPer capita herbivory rate10aPhosphorus10aPlant tissue chemistry1 aLa Pierre, Kimberly, J.1 aSmith, M.D. uhttps://link.springer.com/article/10.1007%2Fs00442-015-3471-702932nas a2200229 4500008004100000245016000041210006900201300001300270490000800283520212300291653001902414653001702433653001502450653001002465653001502475653001402490653001502504100001802519700001802537700001702555856013002572 2010 eng d00aMineralogy and morphological properties of buried polygenetic paleosols formed in late quaternary sediments on upland landscapes of the central plains, USA0 aMineralogy and morphological properties of buried polygenetic pa a508 -5170 v1543 aEast central Kansas is largely comprised of alternating, level beds of Permian shale and limestone of the Central Plains, USA. Polygenetic upland soils of east central Kansas have been formed though multiple and likely different sets of soil forming factors. Upland soils in this region have a complex genesis, often contain one or more paleosols, and form in multiple parent materials including loess, locally reworked loess or colluvium, and residuum. The depth to bedrock rarely exceeds 2 m. Upland hillslope soils commonly contain one or more paleosols, and can be observed on a variety of hillslope positions on the landscape. Generally, the lower paleosols are recognized by strongly expressed structure, thick continuous clay coatings on all faces of peds, and strong reddish color with either 7.5YR or 5YR hues. Soil textures of the paleosols often feel less clayey than the overlying horizons in field determinations. At first, this was attributed to a decrease in clay content, stickiness, and plasticity. However, subsequent laboratory characterization revealed that the clay content was usually highest in the lower paleosol horizons, and that the clay mineralogy of the modern soil was dominated by smectite, while the paleosols contained a mixed suite of minerals. Therefore, the perceived decrease in clay content was caused by a change in clay mineralogy, a feature that can be exploited in future field descriptions in order to more accurately distinguish between stratigraphic units in these thin, welded polygenetic soils. The age of the paleosols sampled in this study were typical for the late Quaternary-aged Severance formation, clustering in two age ranges, which were ≈ 19,000 to 20,000 and ≈ 22,500 to 27,700 uncalibrated 14C yr BP. The results from this study illustrate that although they might be thin, truncated, and welded, late Quaternary-aged loess-derived soils and paleosols occur in regular, predictable patterns on many upland hillslopes in the Bluestem Hills Major Land Resource Area, and this region should be included in future regional investigations of the Central Plains.10aCentral Plains10aGreat Plains10aLandscapes10aLoess10aMineralogy10aPaleosols10aQuaternary1 aPresley, D.R.1 aHartley, P.E.1 aRansom, M.D. uhttp://lter.konza.ksu.edu/content/mineralogy-and-morphological-properties-buried-polygenetic-paleosols-formed-late-quaternary