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Full-Text Articles in Soil Science
Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz
Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz
Graduate Theses and Dissertations
Soybeans (Glycine max) are one of the major row crops in the United States, particularly in Arkansas. Soybean cyst nematode (SCN, Heterodera glycines) and southern root-knot nematode (RKN, Meloidogyne incognita) are two of the most damaging pests that cause major economic losses in soybeans. Little is known concerning the effects of common and alternative agronomic practices on nematodes in fields with nematode population densities below threshold levels. Therefore, the objective of this study was to evaluate the effects of the combination of tillage (conventional tillage and no-tillage), irrigation (irrigated and non-irrigated), wheat (Triticum aestivum) residue burning (burned and no burned), …
Environmental Assessment Of Arsenic And Mercury Levels At The Garfield Mill Site, Calico, California, Steven Gregory Thorp
Environmental Assessment Of Arsenic And Mercury Levels At The Garfield Mill Site, Calico, California, Steven Gregory Thorp
Electronic Theses, Projects, and Dissertations
Environmental impacts of mining at Calico, California, are poorly understood in comparison to the details of its history of silver production. Human health risks associated with arsenic from the lode rock, as well as mercury from the silver milling process, include central nervous system damage, organ failure, and death. To quantify the potential human health risk and manage remediation of this site, tailings from the Garfield Mill site were digitally mapped and chemically analyzed by portable x-ray fluorescence, which permitted volumetric estimates of total mill tailings and the arsenic and mercury budget, as well as identification of anomalies in the …
Landuse And Soil Property Effects On Infiltration And Soil Aggregate Stability In The Lower Mississippi River Valley, Rebecca Lynn Anderson
Landuse And Soil Property Effects On Infiltration And Soil Aggregate Stability In The Lower Mississippi River Valley, Rebecca Lynn Anderson
Graduate Theses and Dissertations
Following European settlement of the Lower Mississippi River Valley (LMRV), agricultural expansion and unsustainable, agriculturally related practices have caused groundwater depletion, soil erosion, and surface water contamination by eroded sediments and sediment-bound nutrients to become major environmental threats to the region. The objective of this study was to evaluate the effects of common landuses [i.e., native prairie, deciduous forest, coniferous forest, Conservation Reserve Program (CRP) grassland, and conventional-tillage (CT) and no-tillage (NT) agriculture] on surface water infiltration and aggregate-stability-related properties [i.e., water-stable macroaggregate (WSA) size distribution, total water-stable macroaggregate (TWSA) concentration, and mean weight diameter (MWD)]. The overall infiltration rate …
Asian Jumping Worm (Megascolecidae) Impacts On Physical And Biological Characteristics Of Turfgrass Ecosystems, Ella L. Maddi
Asian Jumping Worm (Megascolecidae) Impacts On Physical And Biological Characteristics Of Turfgrass Ecosystems, Ella L. Maddi
Honors Theses
Asian Jumping worms (Megascolecid spp) were introduced to North America in the early 1900s and have been altering soils in forest ecosystems as they spread throughout the continent. The worms differ from other introduced earthworms in their ability to consume large densities of organic material and potentially alter nutrient cycling in the ecosystems that they invade (Greiner et al. 2012). This study examined if and how Asian jumping worms alter turfgrass systems by changing the biological or physical properties of soil. To do this we conducted a mesocosm experiment and observational field study. For the mesocosm study we inoculated boxes …
Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman
All Master's Theses
Changing agricultural land-use practices to increase soil carbon sequestration contributes to climate change mitigation and improved food security by moving CO2 from the atmosphere into soil as soil organic carbon (SOC). In 2016, a farm in Thorp, Washington, Spoon Full Farm, began converting land historically farmed using conventional methods of tillage and synthetic fertilizers to conservation farming methods with direct seeding and organic soil amendments with a goal of sequestering carbon in the soil. This project evaluates relationships of soil CO2 respiration and net ecological exchange (NEE) with land-use types, seasonal environmental factors (air temperature, relative humidity, soil …