EFFECT OF Dactyladenia barteri (Hook. f. ex Oliv.), Leucaena leucocephala (Lam.) de Wit, Gliricidia sepium (Jacq.), and Senna siamea (Lam.) MULCHES ON EARTHWORM ACTIVITY AND NUTRIENT TURNOVER IN CASTS
AbstractA two year field study was conducted to investigate the effects of prunings of Dactyladenia barteri (Hook. f. ex Oliv.), Leucaena leucocephala (Lam.) de Wit, Gliricidia sepium (Jacq.), and Senna siamea (Lam.) on the activity of earthworms and soil and worm cast properties. Earthworm activity was measured by quantifying worm casts deposited at the soil surface. Results of the study showed that the effect of the different mulches on earthworm activity was similar. The cumulative trend in surface cast production was also similar under the different mulches. Irrespective of the type of mulch and the year of sampling, the concentration of nutrient elements were significantly (P = 0.05) higher in worm casts relative to uningested soil. Worm casts contain 2 – 3 times more Ca, 2 – 3 times more Mg, 3 – 4 times more K, 5 – 6 times more N and 2 – 5 times more organic C than the top 5 cm of the soil.
[Niger Agric. J. 34 (2003): 27-35]