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From a world-wide plant introduction trial series utilising 25 central American species planted at over 100 sites in nearly 60 countries, eighteen species planted at 15 sites in the tropics were chosen for further study of the factors determining site productivity and site by species interactions. The species were Acacia pennatula, Acacia farnesiana, Albizia guachapele, Ateleia herbert-smithii, Caesalpinia coriaria, Caesalpinia eriostachys, Caesalpinia velutina, Enterolobium cyclocarpum, Gliricidia sepium, Haematoxylon brasiletto, Crescentia alata, Leucaena collinsii, Leucaena leucocephala, Leucaena shannonii, Parkinsonia aculeata, Pithecellobium dulce, Prosopis juliflora and Senna atomaria. The sites were in Haiti (3), Honduras, India (5), Kenya, Mexico, Hawaii. Tanzania (2) and Zambia. After three years there was a four fold variation in the average stem length of the trees between the 15 sites. That variation in growth was associated with increasing sandiness in the soil and increasing soil nitrogen.
From a world-wide plant introduction trial series utilising 25 central American species planted at over 100 sites in nearly 60 countries, eighteen species planted at 15 sites in the tropics were chosen for further study of the factors determining site productivity and site by species interactions. Acacia farnesiana, Albizia guachapele, Ateleia herbert-smithii, Caesalpinia coriaria, Caesalpinia eriostachys, Caesalpinia velutina, Enterolobium cyclocarpum, Gliricidia sepium, Haematoxylon brasiletto, Crescentia alata, Leucaena collinsii, Leucaena leucocephala, Leucaena shannonii, Parkinsonia aculeata, Pithecellobium dulce, Prosopis juliflora and Senna atomaria. The sites were in Haiti (3), Honduras, India (5), Kenya, Mexico, Hawaii. Tanzania (2) and Zambia. After three years there was a four fold variation in the average stem length of the trees between the 15 sites. That variation in growth was associated with increasing sandiness in the soil and increas ing soil nitrogen.