Imbach A.C. Fassbender, H.W. Borel, R. Beer, J. Bonnemann, A.

Modelling agroforestry systems of cacao (Theobroma cacao) with laurel (Cordia alliodora) and cacao with poro (Erythrina poeppigiana) in Costa Rica, 4: Water balances, nutrient inputs and leaching - 1989

The hydrological balances for the agroforestry systems of Theobroma cacao with Cordia alliodora or Erythrina poeppigiana were calculated using measurements taken over four years (1983-1987) of the following parameters: climatic (precipitation evaporation): edaphological (texture, soil moisture tension, hydraulic conductivity, variations in soil moisture content). Water fluxes (interception, simulation of transpiration and percolation) were estimated from one year of measurements (1986-1987). Weekly samples of percolated water were taken from March 1986 - March 1987 using lysimetric capsules at 100 cm soil depth. N, P, K, Ca and Mg concentrations were determined to calculate the annual leaching losses nutrient concentration values were extrapolated for the whole 4 years observation period in order to calculate leaching losses for the whole study period. Precipitation samples were also taken to determine the corresponding annual nutrient inputs. The following values for the hydrological balance were obtained (mm.a): T. cacao 1 year and E. poeppigiana 4 years: Precipitation 1.923, 2.001, Interception 281, 294, Transpiration 702, 707, Percolation 940, 1.000 respectively. T. cacao 1 year and C. alliodora 4 years: Precipitation 1.923, 2.001, Interception 307, 320, Transpiration 702, 707, Percolation 914, 974 respectively. The annual rates of nutrient leaching losses were (kg.ha exponent -1 a exponent -1).


THEOBROMA CACAO
CORDIA ALLIODORA
ERYTHRINA POEPPIGIANA
AGROFORESTERIA
PLANTAS DE SOMBRA
EVAPORACION
TRANSPIRACION
BALANCE HIDRICO
NUTRIENTES
LIXIVIACION
NITROGENO
POTASIO
MAGNESIO
CALCIO
SUELO
PERMEABILIDAD
CICLO BIOGEOQUIMICO

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