00610nam a2200145 a 450000100080000000500110000800800410001910000170006024501540007726001420023165300360037370000190040970000190042870000170044720936302018-07-27       1993    bl uuuu     u00u1 u    #d1 aFELDMANN, F.  aThe environmental changes field preparation in Amazonas require an ecologically adapted agricultural production system to reach economical stability.  aIn: SYMPOSIUM TROPISCHE NUTZPFLANZEN - BIOLOGIE, OKOLOGIE, OKONOMIE, 1993, Hamburg. Abstracts... Hamburg: Universitat, 1993. p. 84.c1993  aSistema de produção agrícola1 aPREISINGER, H.1 aGASPAROTTO, L.1 aLIEBEREI, R.