Search Constraints

Start Over
Filtering by: Subject Soil moisture Remove constraint Subject: Soil moisture License All rights reserved Remove constraint License: All rights reserved

Search Results

  • Water content and electrical conductivity profile measurements for dispersive media using enhanced time domain and frequency domain models

    Creator:
    Flugstad, Benjamin A.
    Abstract:
    Water conservation and water quality are rapidly increasing in importance in all areas of the world. The ability to accurately measure soil water content and salinity, over a wide variety of conditions, is key to meeting this need. A set of forward prediction models and waveform interpretation algorithms to extract...
    Resource Type:
    Dissertation
    Full Text:
    Irrigation) . 240 Figure 4.3a: Soil Moisture Content Measurement Cell w/PCBA at Bottom and Parallel Wire

  • Effects of Initial Moisture and Surface Properties on Sorptivity of Coarse Soil and Sand

    Creator:
    Ambrowiak, Gloria M.
    Abstract:
    Many different models and mechanisms of water imbibition into soil have been described in the literature. Theoretical equations based on those models exist to predict how water will flow in porous media. These models can be useful, but have their weaknesses. Research on imbibition and infiltration into soils has mostly...
    Resource Type:
    Masters Thesis

  • Exploring mechanisms that drive the development of reversible soil hydrophobicity

    Creator:
    Woolverton, Priscilla B.
    Abstract:
    This study focuses on one widespread characteristic of poor soil quality: hydrophobic soil. Previous research has produced conclusive evidence to show that soil hydrophobicity is affected by soil organic matter (SOM) and soil water content (WC). Hydrophobicity that responds to changes in WC is a unique form of surface hydrophobicity...
    Resource Type:
    Masters Thesis
    Full Text:
    ). Hydrophobicity also diverts surface water, inducing spatial variability in soil moisture which gives rise to

  • Characterization of hydrologic parameters and processes in shrink-swell clay soils

    Creator:
    Stewart, Ryan D.
    Abstract:
    Vertisols and other vertic-intergrade soils are found all over the globe, including many agricultural and urban areas. These soils are characterized by their cyclical shrinking and swelling behaviors, where bulk density and porosity distribution both vary as functions of time and/or soil moisture. In turn, alterations in physical soil parameters...
    Resource Type:
    Dissertation
    Full Text:
    soil moisture. In turn, alterations in physical soil parameters become manifest as crack networks

  • Distinguishing biological and physical controls on soil respiration

    Creator:
    Phillips, Claire L.
    Abstract:
    Soil respiration, or the combined CO₂ emissions from roots and soil microorganisms, constitutes one of the largest losses of carbon (C) from terrestrial ecosystems. The major drivers of soil respiration, which include soil moisture, temperature, and substrate quality, have been known for some time. Nevertheless, correlations between these drivers and...
    Resource Type:
    Dissertation
    Full Text:
    ecosystems. The major drivers of soil respiration, which include soil moisture, temperature, and substrate

  • Unsaturated Soils and Foundation Design : Theoretical Considerations for an Effective Stress Framework

    Creator:
    Baker, Josiah D.
    Abstract:
    This study presents the theoretical background necessary to model the bearing capacity of shallow and deep foundations in partially saturated soils. The conventional bearing capacity equations for shallow and deep foundations and the 𝛽-method for deep foundation side resistance have been modified to include the effects of matric suction and...
    Resource Type:
    Masters Thesis
    Full Text:
    ....................................................................19 2.3.1. Soil Water Characteristic Curve

  • Addressing Data Resolution in Precision Agriculture

    Creator:
    Kelley, Jason
    Abstract:
    Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made...
    Resource Type:
    Dissertation
    Full Text:
    irrigation demand. Soil moisture measurement helps determine how much water that is available to crops

  • Ecohydrological mediation of water budget partitioning and time scales of subsurface flow in a seasonally semi-arid grassland

    Creator:
    Pangle, Luke A.
    Abstract:
    Understanding how the interactions and feedbacks between plant function, climate, and soils ultimately affects the terrestrial water balance and subsurface flow processes is major challenge in scientific hydrology. This dissertation summarizes the findings of a manipulative climate warming experiment, an observational field study that utilized stable-isotope tracers, and associated modeling...
    Resource Type:
    Dissertation
    Full Text:
    of evapotranspiration, soil moisture, and potential groundwater recharge to a 3.5˚C temperature

  • Response of Roughstalk Bluegrass (Poa trivialis L.) to Waterlogging Stress

    Creator:
    Liu, Mingyang
    Abstract:
    Roughstalk bluegrass (Poa trivialis L.) (RB) is a weed species that increased very quickly in grass seed production fields of the Willamette Valley. The invasion of RB in grass seed crops often occurs in waterlogged soils. In waterlogged areas, RB exhibited better competitiveness and had greater population densities than other...
    Resource Type:
    Dissertation
    Full Text:
    Crop Science Head of the Department of Crop and Soil Science Dean of the Graduate

  • Improving soil water determination in spatially variable field using fiber optic technology and Bayesian decision theory

    Creator:
    Sayde, Chadi
    Abstract:
    Achieving and maintaining sustainability in irrigated agriculture production in the era of rapidly increasing stress on our natural resources require, among other essential actions, optimum control and management of the applied water. Thus, a significant upgrade of the currently available soil water monitoring technologies is needed. The primary goal of...
    Resource Type:
    Dissertation
    Full Text:
    .............................................................................................. 1 1.1 Uncertainty in Soil Moisture Measurements