3GALLOWAY J N. The global nitrogen cycle: Changea and cortscquences[J]. Environ Pollut, 1998, 102(S1 ) : 15 - 24.
4BUONDONNO A, COPPOLAA E, PALMIERIA G, et al. Monitoring nitrogen forms in soil/plant systems under different fertilizer managements. A preli minary investigation[J]. Eur J Aaron, 1997,7(4) :293 - 300.
5ABAD M B,CLEMENT M D, ARAGAN R P, et al.The influence of solid urban waste compost and nitrogen-mineral fertihzer on growth and productivity in potatoes[J]. Commun Soil Sci Plant Anal, 1997,28(17/18) : 1653 - 1661.
6EVERAARTA A P. Nitrogen balance during growth of cauliflower[J]. Scientia Horticulturae,2000,83(3/4) : 173 - 186.