The need for precise and responsive management of N fertilizer in corn production is compelling for both economic and environmental reasons, but the optimum N rate remains an elusive notion. Economically optimal N rates (EONR) in much of North America may range from zero to 225 lb/A (Scharf et al., 2006; Sawyer et al. 2006), and may vary as the growing season progresses (van Es et al., 2007). M...

The need for precise and responsive management of N fertilizer in corn production is compelling for both economic and environmental reasons, but the optimum N rate remains an elusive notion. Economically optimal N rates (EONR) in much of North America may range from zero to 225 lb/A (Scharf et al., 2006; Sawyer et al. 2006), and may vary as the growing season progresses (van Es et al., 2007). M...

Received: July 25, 2017 Revised: November 23, 2017 Accepted: December 17, 2017 Abstract: Introduction: Due to the water shortage and dry Mediterranean condition, determination of water and nitrogen (N) fertilizer requirements is a major challenge for crop production and environment protection. A field experiment was carried out for two consecutive years (2014 and 2015) to evaluate the response ...

The global abundance of N fertilizer has dramatically increased agricultural productivity. However, when N escapes to the atmosphere as ammonia (NH 3 ) gas, NH 3 loss can cause undesirable effects. In addition to a loss of a valuable resource, it can have negative impacts on air quality, ecosystem productivity, and human health. Animal production is the largest source of NH 3 emission in North ...

A study was done to determine the macroand micronutrient requirements of young northern highbush blueberry plants (Vaccinium corymbosum L. ‘Bluecrop’) during the first 2 years of establishment and to examine how these requirements were affected by the amount of nitrogen (N) fertilizer applied. The plants were spaced 1.2 · 3.0 m apart and fertilized with 0, 50, or 100 kg ha of N, 35 kg ha of pho...

Simple nitrogen (N) input/output balance calculations in agricultural systems are used to evaluate performance of nutrient management; however, they generally rely on extensive assumptions that do not consider leaching, denitrification, or annual depletion of soil N. We constructed a relatively complete N mass balance for the Big Ditch watershed, an extensively tile-drained agricultural watersh...

Human urine was used as a fertilizer in cabbage cultivation and compared with industrial fertilizer and nonfertilizer treatments. Urine achieved equal fertilizer value to industrial fertilizer when both were used at a dose of 180 kg N/ha. Growth, biomass, and levels of chloride were slightly higher in urine-fertilized cabbage than with industrial-fertilized cabbage but clearly differed from non...

Fertilizer efficiency directly affects the production of continuous cropping greenhouse cucumber. So analyzing the fertilizer efficiency is of great significance in providing decision-making support for fertilization of greenhouse cucumber. By establishing the DEA models of continuous cropping greenhouse cucumber and taking existing data samples as study objects, the problems of fertilizer effi...

Data from 139 research sites throughout the Inland Northwest were analyzed for effects of ash cap on site productivity, nutrient availability and fertilization response. Stand productivity and nitrogen (N) fertilizer response were greater on sites with ash cap than on sites without. Where ash was present, depth of ash had no effect on site productivity or N fertilizer response. Site productivit...