01107naa a2200181 a 450000100080000000500110000800800410001902400660006010000160012624500930014226000090023552005560024465300160080070000190081670000200083570000170085577300530087221199852025-03-21       1993    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.2134/agronj1993.00021962008500020032x2DOI1 aCAHN, M. D.  aCation and nitrate leaching in an oxisol of the Brazilian Amazon.h[electronic resource]  c1993  aHigh rates of N fertilizers are often necessary to achieve yield goals in the humid tropics, where subsoil acidity prevents deep crop rooting. However, leaching of fertilizer nitrate may accelerate the leaching of bases from the crop rooting zone, leading to an acidification of the topsoil and a reduction in crop yields. Our objective was to investigate the influence of urea and legume green manure sources of N on crop yields, leaching of cations, and the fertility of the plow layer of a clayey Oxisol (Typic Acrudox) of the central Amazon basin.  aTerra firme1 aBOULDIN, D. R.1 aCRAVO, M. da S.1 aBOWEN, W. T.  tAgronomy Journalgv. 85, n. 2, p. 334-340, 1993.