Productivity and nutrient cycling in young Acacia senegal farming systems on Vertisol in the Blue Nile region, Sudan
Tóm tắt
Acacia senegal, the gum arabic-producing tree, is the most important component of traditional dryland agroforestry systems in the␣Sudan. The spatial arrangement of trees and the type of agricultural crop used influence the interaction between trees and crops. Tree and crop growth, gum and crop yields and nutrient cycling were investigated over a period of 4 years. Trees were grown at 5 × 5 m and 10 × 10 m spacing alone or in mixtures with sorghum or sesame. No statistically significant differences in sorghum or sesame yields between the intercropping and control treatments were observed (mean values were 1.54 and 1.54 t ha−1 for sorghum grain and 0.36 and 0.42 t ha−1 for sesame seed in the mixed and mono-crop plots, respectively). At an early stage of agroforestry system management, A. senegal had no detrimental effect on crop yield; however, the pattern of resource capture by trees and crops may change as the system matures. A significant positive relationship existed between the second gum picking and the total gum yield. The second gum picking seems to be a decisive factor in gum production and could be used as an indicator for the prediction of the total gum yield. Soil organic carbon, N, P and K contents were not increased by agroforestry as compared to the initial levels. Soil OC was not increased by agroforestry as compared to sole cropping. There was no evidence that P increased in the topsoil as the agroforestry plantations aged. At a stocking density of 400 trees ha−1 (5 × 5 m spacing), A. senegal accumulated in its biomass a total of 18.0, 1.21, 7.8 and 972 kg ha−1 of N, P, K and OC, respectively. Agroforestry contributed ca. 217 and 1500 kg ha−1 of K and OC, respectively, to the top 25-cm of soil during the first four years of intercropping.
Tài liệu tham khảo
Allen SE (ed) (1989) Chemical analysis of ecological materials. Blackwell Scientific Publications, Oxford, pp 1–368
Ballal ME, El Siddig EA, Elfadl MA, Luukkanen O (2005) Gum arabic yield in differently managed Acacia senegal stands in western Sudan. Agrofor Forum 63:237–245
Bernhard-Reversat F, Poupon H (1980) Nitrogen cycling in a soil-tree system in a Sahelian savanna. Example of Acacia senegal. In: Rowsswall T (ed) Nitrogen cycling in West African ecosystems. Proc Workshop SCOPE/UNEP International Nitrogen Unit, MAB (UNESCO) and IITA, Ibadan, Nigeria, 11–15 Dec 1978, pp 363–369
Blake GR, Hartge KH (1986) Bulk density. In: Klute A (eds) Methods of soil analysis, Part 1, 2nd edn. Agronomy 9, pp 363–375
Breman H, Kessler JJ (1995) Woody plants in agro-ecosystems of semi-arid regions. Springer-Verlag, Berlin, Germany, 340 pp
Buresh RJ (1995) Nutrient cycling and nutrient supply in agroforestry systems. In: Dudal R, Roy RN (eds) Integrated plant nutrition systems. FAO Fertilizer and Plant Nutrition Bulletin No. 12, Rome, Italy, pp 155–164
Buresh RJ, Smithson PC, Hellums DT (1997) Building soil P capital in sub-Saharan Africa. In: Buresh RJ, Sanchez PA (eds) Replenishing soil fertility in Africa. SSSA Special Publication 51. SSSA and ASA, Madison, WI, USA, pp 111–149
Buresh RJ, Tian G (1998) Soil improvement by trees in sub-Saharan Africa. Agrofor Sys 38:51–76
Colonna JP, Thoen D, Ducosso M, Badji S (1991) Comparative effects of Glomus mosseae and P fertilizer on foliar mineral composition of Acacia senegal seedlings inoculated with Rhizobium. Mycorrhiza 1:35–38
Deans JD, Diagne O, Lindley DK, Dione M, Parkinson JA (1999) Nutrients and organic-matter accumulation in Acacia senegal fallows over 18 years. For Ecol Manage 124:153–167
Droppelmann KJ, Ephrath JE, Berliner PR (2000) Tree/crop complementarity in an arid zone runoff agroforestry system in Northern Kenya. Agrofor Sys 50:1–16
El Houri AA (1986) Some aspects of dryland afforestation in the Sudan with special reference to Acacia tortilis (Forks.) Hayne, Acacia senegal Willd. and Prosopis chilensis (Molina) Stuntz. For Ecol Manage 16:209–221
Feng X (1999) Trends in intrinsic water-use efficiency of natural trees for the past 100–200 years: a response to atmospheric CO2 concentration. Geochem Cosmochim Acta 63:1891–1903
Feng X, Epstein S (1995) Carbon isotope of trees from arid environments and implications for reconstructing atmospheric CO2 concentration. Geochem Cosmochim Acta 59:2599–2608
Govindarajan M, Rao MR, Mathuva MN, Nair PKR (1996) Soil-water and root dynamics under hedgerow intercropping in semiarid Kenya. Agronomy J 88:513–520
Heinemann AM, Otieno HJO, Mengick EK, Amadelo BA (1997) Growth and yield of eight agroforestry tree species in line plantings in western Kenya and their effect on maize yields and soil properties. For Ecol Manage 91:103–135
Huang W (1998) Productive coexistence and gain in agroforestry systems. Doctoral Thesis, Acta For Fen 260. 72 pp
Jewitt TN, Manton JS (1954) Soil exhaustion in the Goz sands of the Sudan. Congres international de la science du sol, leopodville, pp 413–416
Jama BA, Nair PKR, Rao MR (1995) Productivity of hedgerow shrubs and maize under alley cropping and block planting systems in semiarid Kenya. Agrofor Sys 31:257–274
Kaushik N, Kumar V (2003) Khejri (Prosopis cineraria)-based agroforestry system for arid Haryana, India. J␣Arid Environ 55:433–440
Khanna PK (1998) Nutrient cycling under mixed-species tree systems in Southeast Asia. Agrofor Sys 38:99–120
Koskela J, Nygren P, Berninger F, Luukkanen O (2000) Implications of the Kyoto Protocol for tropical forest management and land use: prospects and pitfalls. University of Helsinki Tropical Forestry Reports 22, 103 pp
Langham DR, Wiemers T (2002) Progress in mechanizing sesame in the US through breeding. In: Janick J, Whipkey A (eds) Trends in new crops and new uses. ASHS Press, Alexandria VA, pp 157–173
Lehmann J, Zech W (1998) Fine root turnover in hedgerow intercropping in Northern Kenya. Plant Soil 198:19–31
Lehmann J, Weigl D, Droppelmann K, Huwe B, Zech W (1999) Nutrient cycling in an agroforestry system with runoff irrigation in Northern Kenya. Agrofor Sys 43:49–70
Lott JE (1998) Resource capture and use in semi-arid over story agroforestry systems. PhD thesis, University of Nottingham, UK. 259 pp
Luukkanen O (1991) Global change and the eco-physiology of tropical trees. In: Proc. conference global change: effects on tropical forest, agricultural, urban and industrial ecosystems, Bangkok, 22–24 Oct 1990, ITTO Tech. Series 6, pp 66–71
Njiti CF, Galiana A (1996) Symbiotic properties and rhizobium requirements for effective nodulation of five tropical dry zone Acacias. Agrofor Sys 43:265–275
Olsen SR, Sommers LE (1982) Phosphorus. In: Page AL, Miller RH, Keeney DR (eds) Methods of soil analysis: Part 2 Chemical and microbiological properties. American Society of Agronomy, Madison, Wisconsin, USA, pp 403–430
Ong CK, Leakey RRB (1999) Why tree–crop interactions in agroforestry appear at odds with tree–grass interactions in tropical savannas. Agrofor Sys 45:109–129
Ong CK, Black CR, Wallace JS, Khan AAH, Lott JE, Jackson NA, Howard SB, Smith DM (2000) Productivity, microclimate and water use in Grevillea robusta-based agroforestry systems on hill slopes in semi-arid Kenya. Agric Ecosyst Environ 80:121–141
Oplinger ES, Putnam DH, Kaminski AR, Hanson CV, Oelke EA, Schulte EE, Doll JD (1990) Alternative Field Crops Manual, Sesame Home
Palm CA (1995) Contribution of agroforestry trees to nutrient requirements of intercropped plants. Agric Ecosyst Environ 30:105–124
Raddad EY, Salih AA, Elfadl MA, Kaarakka V, Luukkanen O (2005) Symbiotic nitrogen fixation in eight Acacia senegal provenances in dryland clays of the Blue Nile Sudan estimated by the 15N natural abundance method. Plant Soil 275:261–269
Rao MR, Ong CK, Pathak P, Sharma MM (1991) Productivity of annual cropping systems on a shallow alfisol in semi-arid India. Agrofor Sys 15:51–63
Reddy YVR, Sudha M (1989) Economics of agroforestry system—CRIDAs experience. In: Singh RP, Ahlwat IPS, Ganga S (eds) Agroforestry Systems in India—Research and Development. Indian Society of Agronomy, New Delhi, pp 179–186
Russell EW (1988) In: Allan Wild (ed) Soil conditions and plant growth, 11th edn. Longman Scientific & Technical, John Wiley & Sons, Inc., New York, 991 pp
SAS (1997) JMP statistical package. SAS Institute, Inc., Cary, NC, USA
Sprent J (1995) Legume trees and shrubs in the tropics: N2-fixation in perspective. Soil Biol Biochem 27:401–407