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Full-Text Articles in Agriculture
Land Use And Season Influence Event-Scale Nitrate And Soluble Reactive Phosphorus Exports And Export Stoichiometry From Headwater Catchments, Dustin W. Kincaid, Erin C. Seybold, E. Carol Adair, William B. Bowden, Julia N. Perdrial, Matthew C.H. Vaughan, Andrew W. Schroth
Land Use And Season Influence Event-Scale Nitrate And Soluble Reactive Phosphorus Exports And Export Stoichiometry From Headwater Catchments, Dustin W. Kincaid, Erin C. Seybold, E. Carol Adair, William B. Bowden, Julia N. Perdrial, Matthew C.H. Vaughan, Andrew W. Schroth
College of Arts and Sciences Faculty Publications
Catchment nutrient export, especially during high flow events, can influence ecological processes in receiving waters by altering nitrogen (N) and phosphorus (P) concentrations and relative amounts (stoichiometry). Event-scale N and P export dynamics may be significantly altered by land use/land cover (LULC) and season. Consequently, to manage water resources, it is important to understand how LULC and season interact to influence event N and P export. In situ, high-frequency spectrophotometers allowed us to continuously and concurrently monitor nitrate (NO3−) and soluble reactive P (SRP) concentrations and therefore examine event-scale NO3− and SRP export dynamics. Here we analyzed event NO3− and …
Influence Of Topography And Human Activity On Apparent In Situ 10be-Derived Erosion Rates In Yunnan, Sw China, Amanda H. Schmidt, Thomas B. Neilson, Paul R. Bierman, Dylan H. Rood, William B. Ouimet, Veronica Sosa Gonzalez
Influence Of Topography And Human Activity On Apparent In Situ 10be-Derived Erosion Rates In Yunnan, Sw China, Amanda H. Schmidt, Thomas B. Neilson, Paul R. Bierman, Dylan H. Rood, William B. Ouimet, Veronica Sosa Gonzalez
College of Arts and Sciences Faculty Publications
In order to understand better if and where erosion rates calculated using in situ 10Be are affected by contemporary changes in land use and attendant deep regolith erosion, we calculated erosion rates using measurements of in situ 10Be in quartz from 52 samples of river sediment collected from three tributaries of the Mekong River (median basin areaD46.5 km2). Erosion rates range from 12 to 209mm kyr-1 with an area-weighted mean of 117±49mm kyr-1 (1 standard deviation) and median of 74mm kyr-1.We observed a decrease in the relative influence of human activity from our steepest and least altered watershed in the …
Dating The Incision Of The Yangtze River Gorge At The First Bend Using Three-Nuclide Burial Ages, Devin Mcphillips, Gregory D. Hoke, Jing Liu-Zeng, Paul R. Bierman, Dylan H. Rood, Samuel Niedermann
Dating The Incision Of The Yangtze River Gorge At The First Bend Using Three-Nuclide Burial Ages, Devin Mcphillips, Gregory D. Hoke, Jing Liu-Zeng, Paul R. Bierman, Dylan H. Rood, Samuel Niedermann
College of Arts and Sciences Faculty Publications
Incision of the Yangtze River gorge is widely interpreted as evidence for lower crustal flow beneath the southeast margin of the Tibetan Plateau. Previous work focused on the onset of incision, but the duration of incision remains unknown. Here we present cosmogenic nuclide burial ages of sediments collected from caves on the walls of the gorge that show the gorge was incised ~1 km sometime between 18 and 9 Ma. Thereafter, incision slowed substantially. We resolve middle Miocene burial ages by using three nuclides and accounting for in situ muogenic production. This approach explains the absolute concentrations of 10Be, 26Al, …
Temporal Overlap And Co-Occurrence In A Guild Of Sub-Tropical Tephritid Fruit Flies, Gleidyane N. Lopes, Miguel F. Souza-Filho, Nicholas J. Gotelli, Leandro J.U. Lemos, Wesley A.C. Godoy, Roberto A. Zucchi
Temporal Overlap And Co-Occurrence In A Guild Of Sub-Tropical Tephritid Fruit Flies, Gleidyane N. Lopes, Miguel F. Souza-Filho, Nicholas J. Gotelli, Leandro J.U. Lemos, Wesley A.C. Godoy, Roberto A. Zucchi
College of Arts and Sciences Faculty Publications
Studies of community assembly have emphasized snapshot comparisons of spatially replicated samples from "natural" assemblages. Agro-ecosystems are characterized by relatively little habitat heterogeneity and no dispersal barriers for actively flying insects. Therefore, dynamic patterns of species segregation and aggregation are more likely to reflect the direct or indirect effects of species interactions. We studied the temporal organization of a guild of 21 congeneric species of Anastrepha that colonized fruit orchards in Monte Alegre do Sul, São Paulo, Brazil. This assemblage also included the introduced Mediterranean fruit fly Ceratitis capitata. One hundred six consecutive weekly censuses (11 Jan 2002-16 Jan 2004) …
Temporal And Spatial Monitoring Of Mobile Nanoparticles In A Vineyard Soil: Evidence Of Nanoaggregate Formation, N. Perdrial, J. N. Perdrial, J. E. Delphin, F. Elsass, N. Liewig
Temporal And Spatial Monitoring Of Mobile Nanoparticles In A Vineyard Soil: Evidence Of Nanoaggregate Formation, N. Perdrial, J. N. Perdrial, J. E. Delphin, F. Elsass, N. Liewig
College of Arts and Sciences Faculty Publications
Mechanisms of formation, stabilization, liberation, transport and deposition of nanoparticles and their relationship to contaminant transport remain scarcely investigated in natural porous media. This study investigated nanoparticles mobilized in the pore space of a French vineyard soil by observing mobile soil-derived organic matter (SOM) and minerals in pore fluids over an 8-month monitoring period. Samples were collected in situ and investigated by transmission electron microscopy coupled to electron-dispersive spectroscopy. The main types of nanoparticles transported within the soil were clay, bacteria, SOM and nanoaggregates. Nanometric clay particles were enriched in various metals (Fe, Zn, As and Pb) and organically-derived constituents. …