01243naa a2200217 a 450000100080000000500110000800800410001910000160006024500940007626000090017052006590017965000210083865000120085965000070087165300250087865300100090365300200091370000190093370000170095277300560096916177321995-06-27       1993    bl uuuu     u00u1 u    #d1 aCAHN, M. D.  aAmelioration of subsoil acidity in an oxisol of the humid tropics.h[electronic resource]  c1993  aThis work investigated the effects of amendments of fertilizer N and lime on subsoil acidity and maize rooting depth in an acid soil of the central Amazon basin. A split-plot designed field experiment was conducted on a clayey Oxisol (Typic Acrudox) during a 16-month period. Main plots received 0 or 4 Mt ha-1 of lime. Subplots were four crop sequences: (1) Maize-green manure (Canavalia ensiformes); (2) maize-green manure (Mucuna aterrima); (3) maize-bare fallow, with the maize receiving 300 kg ha-1 of urea-N; and (4) bare fallow, with an application of 300 kg ha-1 of urea-N at the same time as sequence 3. Plots were periodically sampled to 1.2 m.  aAdubação Verde  aCalagem  aPh  aCanavalia ensiformes  aMaize  aMucuna aterrima1 aBOULDIN, D. R.1 aCRAVO, M. S.  tBiol. Fertil. Soilsgv. 15, n. 2, p. 153-159, 1993.