Water balance and nitrate leaching in an irrigated maize crop in SW Spain

Aquatic birds as bioindicators of trophic changes and ecosystem deterioration in the Mar Menor lagoon (SE Spain)

“…The fertiliser inputs and leaching coefficients are close to the values found in other intensive Mediterranean irrigated lands (Guimera`& Candela, 1994;Guimera`et al, 1995;Moreno et al, 1996;Lo´pez Ga´lvez & Naredo, 1996). Although data on water amount and quality in watercourses reaching the lagoon are very scarce, the existing information has allowed a first estimation of the overall retention coefficient of N and P at watershed scale, since empirical values are not available.…”

Safety-net role of tree roots: evidence from a pecan (Carya illinoensis K. Koch)–cotton (Gossypium hirsutum L.) alley cropping system in the southern United States

“…Moreno et al (1996) conducted a study of water balance and nitrate leaching in an irrigated maize crop on a sandy loam in Spain. They found that nitrate leaching during the 3-year study period totaled 43 kg ha À1 under a low fertilization regime (170 kg N ha À1 per year) and 150 kg ha À1 under a high fertilization regime (500 kg N ha À1 per year).…”

“…The respective amounts of NH 4 -N and NO 3 -N that leached below the root zone at 0.3 and 0.9 m depths in barrier and non-barrier treatments were determined using the following equation (Moreno et al, 1996):…”

Salt and nitrate concentrations in the surface waters of the CR-V irrigation district (Bardenas I, Spain): diagnosis and prescriptions for reducing off-site contamination

“…Due to the low irrigation efficiencies found in many surface irrigated districts of the Ebro Basin and elsewhere (Bouwer et al, 1990;Pang et al, 1997;Faci et al, 2000), water, salts and nitrates are lost below the crops root zone polluting the receiving water bodies. Thus, nitrate losses greater than 100 kg N/ha/ year have been measured in semiarid surface irrigated areas in Spain (Cartagena et al, 1995;Moreno et al, 1996) and USA (Devitt et al, 1976;Pratt, 1984). Likewise, salt losses greater than 10 Mg/ha/year have been measured in various surface irrigated Districts of the Ebro Basin (Basso, 1994;Isidoro, 1999).…”