Proceedings
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| Filter results4 paper(s) found. |
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1. The Illinois Nitrogen Soil TestNitrogen fertilizer recommendations for corn production are often estimated on the basis of a realistic yield goal, with adjustments to allow for N credits fiom other sources, such as legumes or manure. A yield-based recommendation may have merit on a long-term basis. but under- or over- fertilization is apt to occur in any given growing season since soil N availability is not taken into account. Insufficient application of N can have serious economic consequences for the farmer, whereas excessive... |
2. Update on the Illinois N TestEstimation of plant-available N is complicated enormously by the dynamic nature of soil N, owing largely to the effects of temperature and moisture supply on N-cycle processes. Numerous biological and chemical methods have been proposed as an index of soil N availability (Brernner, 1965; Keeney, 1982; Stanford, 1982; Bundy and Meisinger, 1994), but none has been adopted widely for soil testing. Biological methods are necessarily time-consuming because of the need for incubation, and the results represent... |
3. An Update on Crop Canopy Sensors for In-Season N ManagementRemote sensing in agriculture has focused 011 the spectral and spatial properties of plants. Remote sensing provides the capability for rapid collection of vast quantities of spatial data that can be analyzed quickly for use in detel-mining a course of action. This creates the potential for using remote sensing to assess and manage in-season production practices. Past research has shown that a change in canopy rel-lectance inay not be unique for a given stress. Also, other agents may have effects... |
4. Hypoxia in the Northern Gulf of Mexico- a 2006 UpdateBased on several science reports and opinions, hypoxia (dissolved oxygen of -Mexico was previously thought to be caused by excessive loads or discharge of nitrogen (N) - primarily as nitrate plus nitrite-N (hereafter referred to as nitrate-N), and exacerbated by fertilizer N inputs (CENR, 2000). These science reports estimated lhat about 90% of the nitrate load to the Gulf was from nonpoint sources in the Mississippi and Atchafalaya River Basin (MARB). They also estimated about 56% of the nitrate-N... |