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Filtering by: Subject Soils -- Herbicide movement Remove constraint Subject: Soils -- Herbicide movement Degree Name Doctor of Philosophy (Ph.D.) Remove constraint Degree Name: Doctor of Philosophy (Ph.D.)

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  • The effect of soil factors on glyphosate availability in soil

    Creator:
    Kawate, Michael Ken
    Abstract:
    Glyphosate (N-(phosphonomethyl)glycine) is an effective foliar-applied herbicide with broad-spectrum activity. Greenhouse and laboratory experiments were conducted to determine the importance of soil moisture, autoclaved soil, soil type, sphagnum peat, soil pH, added phosphorus, and plant residues on crop establishment and growth when glyphosate was applied before emergence of the crop....
    Resource Type:
    Dissertation
    Full Text:
    SOIL. GENERAL INTRODUCTION Glyphosate is an effective foliar-applied herbicide with broad-spectrum

  • Behavior of metribuzin and ethylmetribuzin in soil

    Creator:
    Peek, Daniel C.
    Abstract:
    The behavior of metribuzin [4-amino-6-(1,1- dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one] and ethyl-metribuzin (4-amino-6-(1,1-dimethylethyl)-3- (ethylthio)-1,2,4-triazin-5(4H)-one] in soil was studied to determine if differences in herbicide behavior in soil could explain (a) the inconsistent herbicidal activity of these chemicals and (b) the greater activity of metribuzin, as compared to ethyl-metribuzin. Metribuzin had higher activity than ethyl-metribuzin...
    Resource Type:
    Dissertation
    Full Text:
    quartz sand was lower than in soil when drainage could occur. Herbicide movement was greatest and

  • Water and solute transport : modeling and application to water conservation in layered soil

    Creator:
    Mohammed, Fareed H. A. N.
    Abstract:
    Sandy soils are among the least productive soils because of their inability to store adequate water for plant growth. Their high percolation rate not only allows water to move quickly beyond the root zone, but also washes nutrients below the reach of plant roots. High evaporation occurs from the soil...
    Resource Type:
    Dissertation
    Full Text:
    The objectives 5 2. WATER MOVEMENT IN SOILS 7 2.1 Factors affecting water movement 7 2.2 Soil water

  • Interaction of ethofumesate with dry soil

    Creator:
    McAuliffe, David
    Abstract:
    Previous studies have shown loss of ethofumesate activity when the herbicide was applied to dry soil (2% w/w moisture content) in both field and greenhouse studies, even when rainfall or irrigation was received within a few days. Laboratory studies were conducted to determine the mechanism for this activity loss. Dry...
    Resource Type:
    Dissertation
    Full Text:
    etho- fumesate degradation. To determine the effect of soil type, the herbicide was applied to air

  • Effect of Endothal and certain other selective herbicides on microbial activity in six different soils

    Creator:
    Au, Frederick Hung Fo
    Abstract:
    The effect of Endothal (3, 6-endoxyhexahydrophthalic acid), sodium pentachlorophenate (Na-PCP) and TD-47 (di-N, N-dimethylcocoamine salt of Endothal) on the microbial populations, ammonification, nitrification and respiration in six different soils was investigated. It was found that Endothal at 20 and 200 ppm had no adverse effect on the microbial population, ammonification,...
    Resource Type:
    Dissertation
    Full Text:
    residue of the herbicide in the soil. Associated problems with soil residues are: movement by leaching

  • Hydrolysis and biological degradation of atrazine in soils

    Creator:
    Skipper, H. D. (Horace D.)
    Abstract:
    Detoxification of atrazine in soils results from both chemical hydrolysis and microbial degradation. Infrared analysis was used to study the hydrolysis of atrazine upon interaction with soil colloids and to ascertain the existence of enol, keto, and protonated-keto forms of hydroxyatrazine. Evolution of ¹⁴CO₂ from ¹⁴C-atrazine and ¹⁴C-hydroxyatrazine was indicative...
    Resource Type:
    Dissertation
    Full Text:
    study the hydrolysis of atrazine upon interaction with soil colloids and to ascertain the existence of

  • Moisture influences on bromacil distribution in the soil and resultant uptake and phytotoxicity

    Creator:
    Schreiber, Jonathon Dennis
    Resource Type:
    Dissertation
    Full Text:
    system. The entire quantity of a given amount of herbicide applied to a soil system is not adsorbed, but

  • Interaction of selected herbicides with soil constituents

    Creator:
    El-Madhun, Yousef Abdel Wahab
    Abstract:
    The behavior of six herbicides in soil was studied under controlled laboratory conditions. Sorption of bromacil, chiorotoluron and diuron was assessed by the batch equilibration procedure over a broad range of aqueous phase sorbate concentration. Linear equilibrium sorption constants (K[subscript p]) were slightly higher at 4° C than at 25°...
    Resource Type:
    Dissertation
    Full Text:
    . Temperature affected degradation more than did soil type or initial herbicide concentration. The degradation

  • Simulation and field validation of heat and water flow during soil freezing and thawing

    Creator:
    Pikul, Joseph Lawrence
    Abstract:
    Freeze/thaw cycles are numerous in agricultural soils of the Pacific Northwest. Potential loss of soil by erosion is high whenever a soil thaws from the surface creating a saturated soil overlying an impermeable frozen layer. Field studies were conducted to investigate the effect of surface residue on soil freezing. Residue...
    Resource Type:
    Dissertation
    Full Text:
    cycles Soil frost and heat flux during extended freezing weather Evaporation and water movement during

  • Belowground carbon storage and soil organic matter quality following fertilizer and herbicide applications in ponderosa pine plantations along a site-quality gradient in northern California

    Creator:
    McFarlane, Karis J., 1979-
    Abstract:
    Belowground carbon (C) storage and quality of soil organic matter (SOM) in forest soils have implications for sustainable forest management and C sequestration, but how these pools change in response to management is poorly understood. I investigated whether fertilization and competing vegetation control, applied alone or in combination early in...
    Resource Type:
    Dissertation
    Full Text:
    Forest Enfineering presented on July 27,2007. Title: Belowmound Carbon Storage and Soil Organic