The potential of alley cropping in improvement of cultivation systems in the high rainfall areas of Zambia. III. Effects on soil chemical and physical properties
- 79 Downloads
A detailed study of the soil chemical and physical properties in seven-year-old alley cropping trial containingLeucaena leucocephala andFlemingia congesta in Northern Zambia is described. There was a strong correlation between the maize yield and the total amount of nitrogen applied, both from prunings and fertiliser, suggesting that a major reason for the observed benefit from alley cropping, particularly withLeucaena, was due to an improvement in nitrogen supply.Leucaena produced significantly more biomass, and its leaves had higher concentrations of nitrogen, phosphorous and potassium and lower C/N and C/P ratios than did those ofFlemingia. There was also evidence that the trees had a beneficial effect on other soil chemical properties; under the hedgerows, particularly those ofLeucaena, there were higher levels of organic carbon, Mg, K and ECEC, and pH values were also highest.
It is suggested that higher levels of organic carbon in the alley crop treatments were responsible for the improvements observed in soil physical properties. Lower bulk density, lower penetration resistance, and a higher infiltration rate and pore volume fraction were measured in the alley crops, although there was no significant change in the soil water release parameters.
A deteriorating effect of constant applications of nitrogen fertiliser on soil fertility was observed; as the level of urea application increased, there were significant decreases in Mg, K and pH, increases in Al and soil acidity, and higher penetrometer resistance. These results highlight the urgent need for further research on biological methods of maintaining soil fertility.
Key wordsalley cropping maize nitrogen organic matter soil fertility Leucaena leucocephala Flemingia congesta
Unable to display preview. Download preview PDF.
- Allison FE (1973) Soil Organic Matter and its Role in Crop Production. Elsevier, Amsterdam, 637 ppGoogle Scholar
- Bolt R and Holdsworth I (1987) Farming systems' economy and agricultural commercialisation in the South Eastern Plateau of Northern Province, Zambia. ARPT Economic Studies No. 1, Misamfu Regional Research Station, Kasama, ZambiaGoogle Scholar
- Handawela J (1986) Effect of trees on upland annual agriculture in the low country dry zone of Sri Lanka. In: Prinsley RT and Swift M, eds, Amelioration of Soil by Trees: A Review of Current Concepts and Practices, pp 145–154. London Commonwealth Science CouncilGoogle Scholar
- Hulugalle NR and Kang BT (1990) Effect of hedgerows in alley cropping systems on surface soil physical properties of an Oxic Paleustalf in southwestern Nigeria. J Agric Sci 114: 301–307Google Scholar
- Hvorslev MJ (1951) Time-lag and soil permeability in ground water observations. US Armycorps of engineers. Waterways Experimentation Station Bulletin 36, 50 ppGoogle Scholar
- Kang BT and Ghuman BS (1989) Alley cropping as a sustainable crop production system. Paper presented at an International Workshop on Conservation Farming on Hillslopes, Taichung, Taiwan, 20–29 March 1989Google Scholar
- Kang BT, Grimme H and Lawson TL (1985) Alley cropping sequentially cropped maize and cowpea withLeucaena on a sandy soil in southern Nigeria. Plant and Soil 85: 267–277Google Scholar
- Kang BT, Wilson GF and Sipkens L (1981) Alley cropping maize (Zea mays L) and Leucaena (Leucaena leucocepohala LAM) in southern Nigeria. Plant and Soil 63: 165–179Google Scholar
- Kang BT and Wilson G (1987) The development of alley cropping as a promising agroforestry technology. In: Steppler HA and Nair PKR, eds, Agroforestry — A Decade of Development, pp 227–243 ICRAF, Nairobi, KenyaGoogle Scholar
- Klute A, ed (1986) Methods of Soil Analysis, Part 1: Physical and Mineralogical Methods Amer Soc Agron, Madison, WI, USAGoogle Scholar
- Lal R (1989a) Agroforestry systems and soil surface management of a tropical alfisol. III. Changes in soil chemical properties. Agroforestry Systems 8: 113–132Google Scholar
- Lal R (1989b) Agroforestry systems and soil surface management of a tropical alfisol. IV. Effects on soil physical and mechanical properties. Agroforestry Systems 8: 197–216Google Scholar
- Lal R (1989c) Agroforestry systems and soil surface management of a tropical alfisol. V. Water infiltrability, transmissivity and soil water sorptivity. Agroforestry Systems 8: 217–238Google Scholar
- Lal R and Greenland DJ (1979) Soil Physical Properties and Crop Production in the Tropics. Wiley, Chichester, UK, 551 ppGoogle Scholar
- Matthews RB, Volk J, and Lungu S (1991) The potential of alley cropping in improving cultivation systems in Northern Province, Zambia: the evidence so far. Paper presented at the Regional Conference on Agroforestry Research and Development in the Miombo Ecozone of Southern Africa, Lilongwe, Malawi, June 16–21, 1991. ICRAF, Nairobi, KenyaGoogle Scholar
- Matthews RB, Holden ST, Volk J and Lungu S (1992a) The potential of alley cropping in improvement of cultivation systems in the high rainfall areas of Zambia. I.Chitemene andfundikila. Agroforestry Systems 17: 219–240Google Scholar
- Matthews RB, Lungu S, Volk J, Holden ST and Solberg K (1992b) The potential of alley cropping in improvement of cultivation systems in the high rainfall areas of Zambia. II. Maize production. Agroforestry Systems 17: 241–261Google Scholar
- Mengel K and Kirkby EA (1987) Principles of plant nutrition, 4th ed, pp 247–492. International Potash Institute, Bern, SwitzerlandGoogle Scholar
- Rogowski AS (1972) Estimation of the soil moisture characteristic and hydraulic conductivity: comparison of models. Soil Sci 114: 423–429Google Scholar
- Sanginga N, Mulongoy K and Ayanaba A (1989) Nitrogen fixation of field-inoculatedLeucaena leucocephala (Lam.) de Wit estimated by the15N and the difference methods. Plant and Soil 117: 269–274Google Scholar
- Stromgaard P (1984) Prospects of improved farming systems in a shifting cultivation area in Zambia. Quarterly Journal of International Agriculture 23: 38–50Google Scholar
- Yamoah CF, Agboola AA and Wilson GF (1986a) Nutrient contribution and maize performance in alley cropping systems. Agroforestry Systems 4: 247–254Google Scholar
- Yamoah CF, Agboola AA, Wilson GF and Mulongoy K (1986b) Soil properties as affected by the use of leguminous shrubs for alley cropping with maize. Agriculture Ecosystems and Environment 18: 167–177Google Scholar
- Young A (1989) Agroforestry for soil conservation. Science and Practice of Agroforestry Series No. 4. ICRAF/CAB International Nairobi, KenyaGoogle Scholar