During three consecutive years (1991-93), a field experiment was conducted in 3n intensively irrigated agricultural sail in SW Spain. The maio objective of tbis study was to determine the water flow and nitrate leaching below tbe root zone~ under an irrigated maize crop and after the growing season (bare soil and rainy periad). The experiment was carried out on a furrow irrigated maize crop usi...

To evaluate the process of nitrate accumulation and leaching in surface and ground water, we conducted simulated rainfall experiments. The experiments were performed in areas of 5.3 m2 with bare slopes of 3° that were treated with two nitrogen fertilizer inputs, high (22.5 g/m2 NH4NO3) and control (no fertilizer), and subjected to 2 hours of rainfall, with. From the 1st to the 7th experiments, ...

the aim of this study is to investigate the nitrate adsorption on granular ferric hydroxide (gfh). the effect of factors such as initial concentration of nitrate, ph, contact time, and adsorbent mass were determined. the study was done in laboratory–scale in which synthetic nitrate solutions in a batch reactor were placed in contact with the adsorbent to model adsorption kinetics. it was found ...

The effects of global environmental changes on soil nitrogen (N) pools and fluxes have consequences for ecosystem functions such as plant productivity and N retention. In a 13-year grassland experiment, we evaluated how elevated atmospheric carbon dioxide (CO2 ), N fertilization, and plant species richness alter soil N cycling. We focused on soil inorganic N pools, including ammonium and nitrat...

The incorporation of plant residues into soil not only represents an opportunity to limit soil organic matter depletion resulting from cultivation but also provides a valuable source of nutrients such as nitrogen. However, the consequences of plant residue addition on soil microbial communities involved in biochemical cycles other than the carbon cycle are poorly understood. In this study, we i...

Cooperative Extension Service • Kansas State University • Manhattan Nitrate toxicity Nitrate is a natural product formed from the oxidation of organic compounds. Most of the soil nitrogen absorbed by plant roots is in nitrate form. Normally, nitrate in a plant is rapidly converted to amino acids by the enzyme nitrate reductase. This reduction requires energy from sunlight, adequate water, nutri...

Soil nitrate-nitrogen (NO3-N) data arranged on a three-dimensional grid were analyzed to compare tillage effect on the spatial distribution of residual NO3-N in the soil profile of agricultural plots drained by subsurface tiles. A three-dimensional median-based resistant (to outlier(s)) approach was developed to polish the spatially located data on soil NO3-N affected by directional trends (non...

Nitrogen fertilizer in the form of urea is subject to ammonia volatilization through the activity of the urease enzyme found ubiquitously in soil (Kissel et al., 2008). Nitrate fertilizer is subject to leaching (Randall et al., 2008) or denitrification (Coyne, 2008), depending on the water content of the soil and water movement through the soil. Ammonium forms of N can be fixed (Kissel et al., ...

Nitrogen fertilizer in the form of urea is subject to ammonia volatilization through the activity of the urease enzyme found ubiquitously in soil (Kissel et al., 2008). Nitrate fertilizer is subject to leaching (Randall et al., 2008) or denitrification (Coyne, 2008), depending on the water content of the soil and water movement through the soil. Ammonium forms of N can be fixed (Kissel et al., ...

A high concentration of nitrate (NO3) in surface water threatens aquatic systems and human health. Revealing nitrate characteristics and identifying its sources are fundamental to making effective water management strategies. However, nitrate sources in multi-tributaries and mix land use watersheds remain unclear. In this study, based on 20 surface water sampling sites for more than two years’ ...