A field study was initiated in 1992 to investigate the long-term impacts of beef feedlot manure application (composted and uncomposted) on nutrient accumulation and movement in soil, corn silage yield, and nutrient uptake. Two application strategies were compared: providing the annual crop nitrogen (N) requirement (N-based rate) or crop phosphorus (P) removal (P-based rate), as well as a compar...

This study evaluated the influence of 20 annual land applications of Class B biosolids on the soil microbial community. The potential benefits and hazards of land application were evaluated by analysis of surface soil samples collected following the 20th land application of biosolids. The study was initiated in 1986 at the University of Arizona Marana Agricultural Center, 21 miles north of Tucs...

Iodine biofortification of vegetables can become an alternative (to iodized salt) method of introducing this element into human diet. Development of agronomic rules concerning its application requires detailed evaluation of iodine influence on plant physiological and biological processes including mineral nutrition and quality of yield. The aim of the study was to determine the effect of iodine...

1997). Ferguson et al. (2002) found reduction in soil nitrate concentration due to variable rate fertilizer N High levels of residual soil NO3–N can contaminate ground water application in only 3 out of 12 site-years as compared by leaching through the soil. Our objective was to reduce the level and spatial variability of residual soil NO3–N while maintaining optiwith uniform N application. Mac...

The ability of soil venting to inexpensively remove large amounts of volatile organic compounds (VOCs) from contaminated soils is well established. However, the time required using venting to remediate soils to low contaminant levels often required by state and federal regulators has not been adequately investigated. Most field studies verify the ability of a venting system to circulate air in ...

Soils used for vegetable production in Florida are sandy, have low organic matter content and fertility, and can support the growth of soil-borne pathogens. Some growers choose to apply compost as an antagonistic suppression approach to combat soil-borne disease effects on crop yields or to increase organic matter and improve soil fertility. The objective of this on-farm study was to determine ...