Nitrogen losses from agriculture soils in the loess region of China. Progress report 2, 1994-1995. A cooperation project between Shaanxi Academy of Agricultural Sciences, China and Swedish University of Agricultural Sciences in Mizhi, Yangling and Hanzhong

abonos nitrogenados agricultural soils ammonia ammoniac cereal crops crop yield cultivos de cereales environmental impact eutrophication eutrophisation fertilidad del suelo impact sur l'environnement impacto ambiental leaching lessivage du sol loess loess soils nitrate nitrates nitratos nitrogen fertilizers rendement des cultures rendimiento de cultivos shaanxi soil fertility sol agricole sol de loess urea uree