preliminary nutrient cycling study quantified total and temporal nutrient
inputs via litterfall and pruning residues in two agroforestry systems: (1) Coffea arabica
(perennial crop)-Erythrina poeppigiana (leguminous shade tree); and (2) C. arabica-E.
poeppigiana-Cordia alliodora with emphasis on the effect of the timber tree C. alliodora.
The total annual input of litterfall plus pruning residues was similar in both associations.
Total annual input from E. poeppigiana was less than half in the asssociation with C.
alliodora than without, but the litterfall from this latter species compensated for the
loss. Large differences in the total annual nutrient input of K, Ca and Mg was found
between associations, but not for N or P. The amount of nutrients recycled by the
associated trees reached the recommended level of fertilizer required for coffee production.
The inclusion of C. alliodora within the C arabica-E, poeppigiana association
resulted in a more evenly distributed annual nutrient input.