1,393 research outputs found
Using Topographic Maps in Extension
Enclosed is an index of available topographic maps, as of September, 1990, which covers the entire state. Most counties will need twelve maps to obtain complete coverage. county agents will find that these maps will significantly aid producers in making decisions about pond locations, drainage, location of structures, elevation differences, slopes, etc. Detailed topographic maps can be obtained from: KY Geological Survey228 Mining & Mineral Resources Bldg.University of KentuckyLexington, Ky 40546-0107 Eastern Distribution BranchU.S. Geological Survey1200 South Eads StreetArlington, VA 22202 Western Distribution BranchU.S. Geological SurveyFederal Center, Box 25286Denver, CO 8022
Trickle Irrigation Installation for Horticulture Crops
Course Outline Trickle Irrigation Overview Design Planning Water Supply Basic Trickle Irrigation System Design Drawing Installation Emitter Clogging Problems Irrigation Schedulin
File Editing on the HP3000 for the SEDIMOT II Computer Model
Since the release of the SEDIMOT II model, the Agricultural Engineering Department has taught approximately 300 consulting and mining engineers, reclamation specialists, government agency personnel, and academia. The program is being used on all types of computer systems, company owned as well as time sharing vendors. Over 50 firms are using the HP3000 system of the College of Agriculture at the University of Kentucky under arrangements with the Institute for Mining and Minerals Research, Office of Informational Services and Technical Liaison
Hydrologic Models
Water is a vital part of our everyday lives. Water is necessary for domestic activities such as drinking, cooking and cleaning; agricultural practices such as growing crops and livestock; and industrial uses such as manufacturing and transporting products (Figure 1). Some of our water use is seen, such as when we take a shower. However, most of our water use is hidden, meaning that water was used to make a product although little to no water may be in the product itself. Because water is so important, a branch of science is devoted to its study
Comparison of Water and Temperature Distribution Profiles Under Sand Tube Irrigation
Drip irrigation is one of the most efficient systems in delivering water to the plant root zone. Research has shown that the saturated, or nearly saturated, surface beneath the emitter may increase evaporation thereby reducing the irrigation efficiency. To increase the efficiency of surface applied drip irrigation on permanent tree crops a sand tube irrigation (STI) method was developed and tested. The sand tube method consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was designed and instrumented to directly measure temporal evaporation during irrigation and for a period of three days after irrigation ceased. Thermocouples were used throughout the soil profile to detect the temperature variation and also to determine temporal movement of the wetting front. The results indicated that for the surface applied drip irrigation method, approximately 30% of the applied water evaporated during the four-day period after irrigation. The STI method resulted in approximately 4% of the applied water being evaporated. The STI method allowed more water to remain in the soil profile thereby increasing the irrigation efficiency
Evaporation Reduction Potential in an Undisturbed Soil Irrigated with Surface Drip and Sand Tube Irrigation
The efficiency of drip irrigation is highly dependent on evaporation losses occurring from the constantly saturated soil beneath emitters. Advent of subsurface drip irrigation is in part an approach to curb this inefficiency. An irrigation method, Sand Tube Irrigation (STI), is proposed to increase the efficiency of “Normal” surface applied drip Irrigation (NI method) on permanent tree crops without the need for burying the irrigation tubing. The sand tube consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was constructed in the laboratory and instrumented to directly measure temporal evaporation from large, undisturbed soil columns, 0.7 m in diameter and 0.8 m in height. Experiments were performed on six replicated soil monoliths to compare the two methods. The results indicated that, for four consecutive days after irrigation, there was a significant difference at the 95% confidence level between evaporation occurring from the NI and STI methods. After four days of evaporation, comparison of water contents indicated that a higher amount of water existed between the depths of 0.2 to 0.55 m in the STI versus the NI method. Although drainage occurred from the macropore structure of the undisturbed soil monoliths, the STI method showed potential in retaining more water in the micropore structure of the lower depths, that would be available for plant use rather than potential evaporation
Micro-Sprinkler and Fan Cooling for Dairy Cows: Practical Design Considerations
Research and on-farm demonstrations have shown that micro-sprinklers, spray jets and fan cooling systems can be effective in relieving heat stress in dairy cows under hot, humid conditions. Based on these results, many dairymen are considering installing sprinkler and fan cooling. Several Kentucky dairymen have already installed sprinkler cooling systems, but they could improve their performance by modifying them to take into account the principles involved and the components used in sprinkler and fan cooling
Designing Contour Weep Berms to Reduce Agricultural Nonpoint Source Pollution
Nonpoint source pollution (NPS) of surface waters is a significant issue in agricultural lands, and best management practices (BMPs) are often used to reduce these impacts. Since the effectiveness of a BMP depends on a large number of widely varying factors, it is important to continue to develop BMPs in order to provide designers with more tools to use to maximize NPS removal. The contour weep berm is a new structural BMP constructed out of earth and subsequently vegetated. It is a linear BMP that is used in combination with a down-gradient vegetated filter strip or forested riparian buffer. Preliminary field evaluations of the contour weep berm indicate it is effective at reducing runoff volumes and peaks, promoting infiltration, and reducing sediment concentrations in runoff. Procedures for designing a contour weep berm are presented along with a design example. Linear BMPs, such as the contour weep berm, can provide producers with another means of effectively controlling NPS
Modeling Surface and Subsurface Pesticide Transport Under Three Field Conditions Using PRZM-3 and GLEAMS
Contaminant transport models should be evaluated over a wide range of conditions to determine their limitations. The models PRZM and GLEAMS have been evaluated many times, but few studies are available in which predicted movement in runoff and percolate were simultaneously evaluated against field data. Studies of this type are essential because pesticide leaching and runoff are mutually dependent processes. For this reason, PRZM-3 and GLEAMS were evaluated for their ability to predict metribuzin concentrations in runoff, sediment, subsurface soil, and pan lysimeters under three field conditions (yard waste compost amended, no-till, and conventional-till) on a Lowell silt loam soil. Sensitive input parameters were either site specific (climatic, soil, and chemical) or calibrated (K-factor, C-factor, curve number). In general, both models under-predicted metribuzin concentration in runoff water, runoff sediment, subplow layer soil (15-75 cm), and pan lysimeter water (75 cm). Contrary to field data, both models predicted that a large percentage (\u3e 50%) of metribuzin would move below the “mixing zone” (top 1 cm) during the first rainfall event after application. Relatively little metribuzin was predicted to move beyond the plow layer (top 15 cm) into the pan lysimeters or subsurface soil throughout the simulation period, possibly due to the lack of a macropore component in the models. High metribuzin concentrations in sediment (field data) indicated that relatively little metribuzin moved below the “mixing zone”, possibly because of hysteresis but much of the metribuzin that did move was quickly transported into the pan lysimeters, probably due to macropore flow. GLEAMS more accurately predicted pesticide concentration in sediment and PRZM predicted subsurface soil concentration somewhat more accurately than GLEAMS. Little difference in accuracy was detected between models on metribuzin concentration in runoff or metribuzin concentration in percolate. Although both models generally under-predicted metribuzin concentration in runoff, runoff transport (mass of metribuzin in runoff) for the study period was over-predicted by both models which emphasizes the importance of accurately predicting herbicide concentration and runoff volume soon after application when the surface pesticide concentrations are highest
Development and Deployment of a Bioreactor for the Removal of Sulfate and Manganese from Circumneutral Coal Mine Drainage
Surface mining, in the form of contour mining and mountain-top removal, is a common means for retrieving coal in the Appalachian Coal Belt region of Kentucky. Overburden or excess spoil generated by these two methods is placed in valley fills. Traditionally Constructed fills have been shown to adversely impact headwater ecosystems via stream burial and through alterations to the hydrology, sediment supply, water quality and biological composition of downstream reaches. Mine drainages emanating from the toe of valley fills often contain elevated levels of total dissolved solids and heavy metals. Drainage chemistry from Guy Cove, a valley fill located in eastern Kentucky, exhibited a mean pH of 6.5 and Fe, Mn and SO4 concentrations of 1.5, 14, and 1264 mg L-1, respectively. The objective of this research was to develop an anaerobic bioreactor for the purpose of reducing Mn and SO4 concentrations in the mine drainage. Development began with batch experiments that tested five different organic carbon sources and five different inorganic substrates. A synthetic mine drainage with a pH of 6.2 and Mn and SO4 concentrations of 90 and 1,500 mg/L, respectively, was used in the experiment. Manganese and SO4 removal varied widely between treatment matrices, with removal rates \u3c 10 to 100% for Mn and \u3c 10 to \u3e 80% for SO4. The substrate sources which provided the most treatment were hardwood mulch and biosolids combined with creek sediment. Subsequent experiments were performed using the synthetic mine drainage in small bioreactors (55 liter plastic tanks) filled with creek sediment with either hardwood mulch or biosolids, each replicated three times. Over a 65 day treatment period \u3e 90% of the Mn and 70% of the SO4 was removed. There were no statistical differences between the two organic substrates. Using this information, in-situ bioreactors consisting of two 5,500 liter plastic septic tanks filled with creek sediment, hardwood mulch and manure compost were installed at Guy Cove. Mine drainage was collected in a sump and conveyed through the inline bioreactors by gravity. Gate valves were used to control flow through the bioreactors. After a 10-month monitoring period, the in-situ bioreactors removed 12, 11, and 64% of Mn, SO4 and Fe from the drainage, respectively. Results from the field differed greatly from those observed under controlled laboratory conditions. Efforts to improve the efficiency of the in-situ bioreactors are underway
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