Abstract
Soil physical properties were measured on field runoff plots established on a tropical Alfisol in Western Nigeria. Evolution of soil physical properties was assessed over a period of 6 years beginning in 1982 (when soil was cleared off its secondary regrowth) till 1987. Changes in soil physical properties were measured for six systems including plow-till, no-till, contour hedgerows of Leucaena leucocephala established 2- and 4-m apart, and contour hedgerows of Gliricidia sepium established 2- and 4-m apart. Soil physical properties were measured once every year during the dry season following the harvest of second season crops.
Over the 6-year period, there were no significant differences in relative contents of textural separates of sand, silt and clay for the surface 0–5 and 5–10 cm layers. The gravel concentration of the surface 0–5 and 5–10 cm layers, however, increased significantly due to plowing and mixing of the surface and subsoil layers. Soil bulk density of 0–5 and 5–10 cm layers, respectively, increased in all treatments from initial values of 1.02 and 1.16 g cm−3 in 1982 to 1.43 and 1.65 g cm−3 at the end of cropping cycle in 1986. The maximum increase in soil bulk density was observed for the no-till treatment. Accordingly, there was an increase in penetration resistance of the surface 0–5 cm layer from an average value of 25.3 kPa in 1982 to 210.7 kPa in 1986. The highest penetration resistance (353 kPa) of 5–10 cm layer was recorded for the no-till treatment. In accord with total porosity, the gravimetric soil moisture retention at zero suction was the lowest for the no-till and the highest for a Gliricidia-based system. There were significant improvements in available water capacity (AWC) of the soil by both Leucaena and Gliricidia-based systems. In comparison with the no-till system, increase in AWC by Leucaena- and Gliricidia-based systems, respectively, was 42 and 56 percent by weight for 0–5 cm depth and 12 and 58 percent by weight for 5–10 cm depth. Alterations in pF curves by agroforestry-based systems were attributed to improvements in soil structure and structural porosity.
Similar content being viewed by others
References
Aina, PO (1979) Soil changes resulting from longterm management practices in western Nigeria. Soil Sci Soc Am J 43: 173–177
Humbel, FX (1975) A study of soil-macroporosity based on permeability data: application of a filtration model to ferralitic soils of Cameroon. Cah ORSTOM Pedologie 13: 93–117
King, KFS (1979) Agroforestry and the utilization of fragile ecosystems. Forest Ecol Management 2: 161–168
Lal, R (1980) Physical properties. In BKG Theng (ed.) ‘Soils with Variable Charge.’ DSIR, New Zealand
Lal, R (1981) Deforestation and hydrological problems. In: R Lal and EW Russell (eds.) ‘Tropical Agricultural Hydrology’, J Wiley & Sons, UK 482 pp
Lal, R (1985) Mechanized tillage systems effects on physical properties of an Alfisol in watersheds cropped to maize. Soil Till Res 6: 149–161
Lal, R (1989) Agroforestry systems and soil surface management of a tropical Alfisol. I. Crop growth and soil moisture: Agroforestry Systems 8: 7–29
Moormann FR, Lal R and Juo ASR (1975) Soils of IITA. IITA Tech Bull 3, 38 pp
Okigbo BN and Lal R (1980) Residue mulches, intercropping and agrisilviculture potential in tropical Africa. In: S Hill (ed.) ‘Basic Techniques in Ecological Farming.’ IFOAM Conference Montreal, Canada: 54–64
Patnaik, N (1978) Soil conservation and watershed management for flood retardation and prevention. Indian J Soil Conservation 6: 43–55
Pereira, HC (1973) Landuse and Water Resources. Cambridge Univ Press, UK, 246 pp
Pereira, HC (1979) Hydrological and soil conservation aspects of agroforestry. In: HO Mongi and PA Huxley (eds) ‘Soils Research in Agroforestry’, ICRAF, Nairobi: 315–326
Takahashi, T, Nagahori, K, Mongkolasawat, C and Cosiriku, M (1983) Runoff and soil loss in shifting cultivation. In: K Kyuma and C Pairintra (eds) ‘Shifting Cultivation’. Ministry of Science & Technology, Bangkok, Thailand: 84–109
Vergara, NT (1982) New directions in agroforestry: The potential of tropical legume trees. E.P.I. East-West Centre, Honolulu, Hawaii, 36 pp
Weert, R Van der and Lenselink, KJ (1972) The influence of mechanical clearing of forest on some physical and chemical properties. Surinaamse Landbouw 20: 2–14
Wood, HB (1977) Hydrological differences between selected forested and agricultural soils in Hawaii. Soil Sci Soc Amer J 41: 132–136
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lal, R. Agroforestry systems and soil surface management of a tropical alfisol:. Agroforest Syst 8, 197–215 (1989). https://doi.org/10.1007/BF00129649
Issue Date:
DOI: https://doi.org/10.1007/BF00129649