The purpose of this field study was to determine the relationship between environmental conditions, particularly high nitrate (NO3 ), low salinity events, and both nitrogen (N) storage (NO3 , ammonium [NH4 ], free amino acids [FAA], protein, and total N) and nitrate reductase (NR) activity in the macroalgae Enteromorpha lingulata and Gelidium pusillum in the lower Mobile Bay estuary (Alabama, U...

Long-term applications of organic or inorganic sources of N to croplands can increase the leaching potential of nitrate– nitrogen (NO3–N) for soils underlain by subsurface drainage ‘‘tile’’ network. A field study was conducted for 6 years (1993– 1998) to determine the effects of liquid swine manure and urea ammonium nitrate (UAN) solution fertilizer applications on NO3–N concentrations and NO3–...

Accounting for the fate of inorganic N fertilizer in agricultural systems is critical to sustainable production. Sebilo et al. (1) provide a unique long-term record of NO3 fertilizer fate that demonstrates N molecules from a discrete fertilizer application are transferred to soil organic matter (SOM) and subsequently mineralized over the course of approximately 100 y, during which they contribu...

High-elevation red spruce [Picea rubens Sarg.]-Fraser fir [Abies fraseri (Pursh.) Poir] forests in the Southern Appalachians currently receive large nitrogen (N) inputs via atmospheric deposition (30 kg N ha(-1) year(-1)) but have limited N retention capacity due to a combination of stand age, heavy fir mortality caused by exotic insect infestations, and numerous gaps caused by windfalls and ic...

Manure application increases pasture crop production and minimizes manure storage costs. Excess N not absorbed by pasture vegetation can leach past the root zone and into ground water. A yearlong study was conducted on grazing pastures at 2 dairy farms to monitor potential nitrate (NO3) movement from the surface through the soil profile toward ground water. Precipitation, irrigation, manure app...

In most aerobic soils, nitrate (NO3(-)) is the main nitrogen source for plants and is often limiting for plant growth and development. To adapt to a changing environment, plants have developed complex regulatory mechanisms that involve short and long-range signalling pathways in response to both NO3(-) availability in the soil and other physiological processes like growth or nitrogen (N) and ca...

Reaction of thiodiacetate anion (tda) with [Cu(TMEDA)(NO3)2] (TMEDA = N,N,N'N'-tetramethyl ethylene-diamine) in a stoichiometric ratio afforded the complex {[Cu(TMEDA)(tda)]·(H2TMEDA)(NO3)2·H2O} (1). When [Cu(TMEDA)(NO3)2] was added in excess, it yielded a μ-oxalato complex {[Cu2(TMEDA)2(μ-ox)(H2O)2](NO3)2·2CH3CN} (2). The reaction involves a facile room temperature desulfurization of the thiod...

Soil nitrate (NO3) tests are an integral part of nutrient management in annual crops. They help growers make field-specific nitrogen (N) fertilization decisions, use N more efficiently and, if necessary, comply with California’s Irrigated Lands Regulatory Program, which requires an N management plan and an estimate of soil NO3 from most growers. As NO3 is easily leached into deeper soil layers ...

This laboratory study examined the use of various wood materials as a carbon source in horizontal flow filters to denitrify nitrate-nitrogen (NO3-N) from a synthetic wastewater. The filter materials were: sawdust (Pinus radiata), sawdust and soil, sawdust and sand, and medium-chip wood chippings and sand. Two influent concentrations of NO3-N, 200 mg L(-1) and 60 mg L(-1), loaded at 2.9 to 19.4 ...