01877nam a2200253 a 450000100080000000500110000800800410001910000170006024501650007726000160024230000140025850000230027252011500029565000210144565000250146665000180149165000210150965000130153065000130154365000120155665000270156865000110159565300170160616645492017-07-31       2002    bl uuuu  m   00u1 u    #d1 aEMMERICH, S.  aDie Feinwurzelsysteme von vier tropischen Nutzbäumen, ihre Nährstoffaufnahme und ihre Interaktionen in einer agroforstlichen Mischkultur in Zentral-Amazonien.  a2002.c2002  c1 CD-ROM.  aTese de Doutorado.  aExtended deforestation of virgin rain forest in Central Amazon is mainly the result of clear cuttings for agricultural purposes. Under the climatic and soil conditions, these cleared areas can be used only for a few years. Development and optimising of agro-ecological produtcion systems, which allow a sustainable land use, will reduce deforestation of virgin rain forest. Agroforestry systems with a mixture of useful trees and herbaceous crops are more suitable for maintaining the soil fertility than systems composed of annual crops only. Roots and root systems of 4 tropical useful trees were investigated in an agroforestry system in Manaus, Brazil, 4-6 years after planting. The Amazon native species Bactris gasipaes (Peach palm, pupunha, use: fruits and palm hearts), Bertholletia excelsa (Brazil nut, castanha do Brasil, use: nuts and wood), Theobroma grandiflorum (largeflowered Cacao, cupuaçu, use: fruits) and Bixa orellana (Orlean tree, urucum, use: dye) received 30% of the full fertilization recommended by the agricultural research institution in Manaus (Embrapa), which was applied twice a year in the stem area of the trees.  aBactris Gasipaes  aBertholletia Excelsa  aBixa Orellana  aCastanha do Para  aCupuaçu  aEspécie  aPupunha  aTheobroma Grandiflorum  aUrucum  aAgrofloresta