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Showing 1 to 20 of 58 for “"Agriculture, Soil Science"”.
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Effect of Turfgrass on Soil Mobility and Dissipation of Several Pesticides
… several pesticides applied to turfgrass and bare soil was studied under field conditions. Cyproconazole [alpha-(4-chlorophenyl)-alpha-(1-cyclopropylethyl)-1H-1,2,4-triazole-1-ethanol] was applied to bare soil (Flanagan silt loam) and creeping bentgrass (Agrostis palustris Huds.) turf containing …
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Soil Spatial Variability: Structures, Models, and Their Effects on Crop Yield Variability
… variables accounted for more than 80% of total soil variability. Component regression accounted for about 52%, and 39% of soybean and corn yields variability respectively. Particle size distribution and organic matter by influencing moisture and nutrient dynamics, were the most important factors …
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Anaerobic Dissipation of Herbicides in Microbiologically Induced Soil Redox Regimes
… may encounter anaerobiosis as a result of soil flooding, poor drainage, or offsite transport. Anaerobic dissipation of herbicides in the environment is poorly understood. The objective of this research was to characterize the anaerobic fates of herbicides atrazine, trifluralin, and …
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Tillage Effects on Soil Properties and Crop Production in Southern Illinois
The Harris et al. (1996) soil quality index (SQI) model was tested and modified according to local and regional conditions by changing the threshold limits and standardized scoring functions (SSF) for soil quality indicators. Soils that had been in 8 years of the NT system had SQI of 0.64 as …
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Soybean Response and Weed Control With Flumioxazin, and Sorption, Degradation, and Weed Control With Isoxaflutole
… of isoxaflutole was found to be more rapid in a soil solution than in a soil-free system. The sorption of isoxaflutole was 6 to 12-fold greater for isoxaflutole than diketonitrile based on Freundlich Kd values calculated from batch isotherms. The effect of moisture, temperature, and biological …
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Factors Affecting the Control of Corn Rootworms With Soil Insecticides: Insecticide Resistance, Distribution, and Persistence
The soil from four fields was evaluated for the persistence of terbufos and carbofuran. For terbufos, there were no significant differences in its persistence in soil from each field and that of its respective border. For carbofuran, no degradation was observed in soil from a field where it had …
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Tile -Drained Watershed Scs-Curve Number Model
Tile flow can be quantified using the altered SCS-CN method. Through theory analogy, a procedure similar to the traditional SCS-CN method was developed to estimate tile flow from rainfall. However, the relationship between initial abstractions and potential maximum retention was redefined. Curve …
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Spatial Variability of Corn Response to Nitrogen Fertilizer: Implications for Variable Rate Fertilization
… analyze the spatial variability of the Illinois Soil Nitrogen Test (ISNT). On-farm experiments were conducted in sixteen fields in Illinois using production agriculture equipment. Site-specific production functions for corn nitrogen fertilization were developed based on terrain attributes, the …
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Quality Soil Management in Illinois Using Winter Cover Crops
… of information regarding the effects of WCC on soil productivity. The objective of this study was to assess the effects of different crop rotations on several soil physical and chemical properties. Three crop sequences including WCC were compared with winter fallowing (control) in a corn (Zea …
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Managing Continuous Corn for Yield and Soil Productivity
… to understand how this transition will affect soil organic matter (SOM). Soil samples were collected following corn from three locations after 8 yr of CC and CS rotations. Soil organic C (SOC) and total N after 8 yr were greater with CC than with the CS rotation, but only at one location where …
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Evaluation of Macrolide-Lincosamide-Streptogramin B Antimicrobial Resistance at Swine Farms
Antimicrobial use in animal agriculture contributes to increased levels of antimicrobial resistance in the environment. To better evaluate this concern, the levels of macrolide-lincosamide-streptogramin B (MLSB) antimicrobial resistance at swine farms were quantified. A variation of fluorescence in …
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Axial Capacity of Drilled Shafts
Less scatter is demonstrated for shafts in clay versus those in sand. More scatter is apparent for shafts constructed using slurry. Little scatter is shown for cased shafts. No trend is shown for slump, date of construction, or type of drilling tool. No significant effect is found for the rate of …
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Sodium Transfer in Biofiltration Wetland Sediments
The model generally predicted the sediment sodium concentration consistent with the sodium measured in seasonal sediment samples. The model was especially sensitive to changes in sodium concentrations in the overlying water and was also sensitive to changes in both the sediment porosity and clay …
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Geotechnical Properties of Peat and Related Engineering Problems
Among the results of this research, complete sets of geotechnical properties of Middleton and James Bay peats were obtained. Such results will provide an idea about the order of magnitude of geotechnical parameters as well as the behavior of these parameters under changing conditions and with time. …
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Factors Influencing the Distribution, Growth and Infectivity of Casuarina-Infective Frankia
… cladodes increased the infectivity of a soil inoculum by a factor of 3.2, whereas leaves of a sympatric check plant, Terminalia catappa (Combretaceae), barely increased the same soil's infectivity. Charcoal and clay added to the seedling growth substrate to bind organic material …
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Actinorhizal Plant Nodulation and Nitrogen Fixation in Natural and Experimental Systems
In a separate study, water-retentive polymer carriers of Frankia inoculum were applied as a root dip to Alnus glutinosa and Casuarina equisetifoloia seedlings. This treatment increased nodulation 5- to 10-fold in greenhouse experiments and also of A. glutinosa in a field experiment.
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An Approach to Using Labile Soil Nitrogen Measurements for Calibration of the Dssat-Century Agroecosystem Model for Site-Specific Nitrogen Fertilizer Management in Illinois, Unites States
… relationships between the modeled variables and soil N fractions as the ISNT. If such relationships can be identified, it should be possible to use site-specific measurements of soil N fractions to better predict crop responses to fertilizer applications. Although it was possible to obtain …
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Pesticide Adsorption and Degradation Properties as Influenced by Iron Oxidation State in Clay Minerals
Reduction of structural Fe in the clay greatly increased the adsorption and produced substantial degradation of all pesticides. When reacted with chemically treated clays, the total amount of atrazine removed from solution by the reduced clay was much greater than by the oxidized or reoxidized …
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Variability Structure Estimation: The Role of Sample Support
The characterization of spatial variability in soil properties is a prerequisite to many activities, such as site specific management (i.e., precision farming), groundwater and solute transport modeling, groundwater pollution assessment and remediation, etc. Due to soil heterogeneity, statistical …
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Estimating Soil Moisture and Energy Fluxes Using Assimilation of Remotely Sensed Land Surface State Variables
Soil moisture plays a critical role in the land-atmosphere interactions. Given the approximate model physics representation in the land surface models predicting these fluxes, better predictions can be obtained by assimilating hydrologically relevant remotely sensed data into the predictive models. …
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