Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-23T07:17:50.509Z Has data issue: false hasContentIssue false

ZAI IMPROVES NUTRIENT AND WATER PRODUCTIVITY IN THE ETHIOPIAN HIGHLANDS

Published online by Cambridge University Press:  14 January 2011

TILAHUN AMEDE*
Affiliation:
International Livestock Research Institute and Challenge Programme on Water and Food, P.O. Box 5689, Addis Ababa, Ethiopia International Water Management Institute, Addis Ababa, Ethiopia
MESFIN MENZA
Affiliation:
Wollega University, Ethiopia
SELESHI BEKELE AWLACHEW
Affiliation:
International Water Management Institute, Addis Ababa, Ethiopia
*
Corresponding author: [email protected]

Summary

In the East African highlands, crop yields tend to increase with proximity of the farm plots to homesteads. Farmers identified soil erosion as the most detrimental cause of low crop yield in the outfields followed by soil compaction due to livestock trampling. The main objective of this study was to determine whether zai pits (i.e. small water harvesting pits) developed for dryland regions of the Sahel could increase crop yield and water productivity of degraded outfields in high rainfall areas, where mean annual rainfall exceeds 1300 mm but soil water infiltration is reduced by slope, low soil organic matter and hardpans. The pits were enlarged to resist strong runoff flows. The research was conducted over three years from 2004 to 2006. Potatoes and beans were used as test crops. Overall, compared to control plots, the zai pits, in combination with nitrogen (N) inputs, increased potato yields from 500% to 2000% (p ≤ 0.001). The pits contributed more to increased crop yield than N inputs. Similarly, bean yields from the zai pits were up to 250% higher. Crop water productivity was 300–700% higher with zai pits than with control plots. The income of farmers who used zai pits was up to 20-fold higher than the labour costs required to prepare them. Contrary to conventional wisdom, this study reveals that the major constraint of the outfields is not nutrient deficiency per se rather low soil water holding capacity, which hinders crop growth and efficient utilization of available nutrients.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Abayomi, Y. A., Fadayomi, O., Babatola, J. O. and Tian, G. (2001). Evaluation of selected legume cover crops for biomass production, dry season survival and soil fertility improvement in a moist savannah location in Nigeria. African Crop Science Journal 9:615627.CrossRefGoogle Scholar
Amede, T. and Delve, R. (2008). Modelling crop-livestock systems for achieving food security and increasing production efficiencies in the Ethiopian highlands. Experimental Agriculture 44:441452.CrossRefGoogle Scholar
Amede, T. and Taboge, E. (2007). Enhancing farmer innovation through manipulation of soil fertility gradients in enset systems. In Improving human welfare and environmental conservation by empowering farmers to combat soil fertility degradation, 289297. (Ed. Bationo, A.). African Soils Network, Springer Verlag.Google Scholar
Amede, T., Belachew, T. and Geta, E. (2001). Reversing the degradation of arable land in Ethiopian Highlands. Managing African Soils No. 23. International Institute for Environment and Development, London.Google Scholar
Amede, T., Descheemaeker, K., Peden, D. and van Rooyen, A. (2009). Harnessing benefits from improved livestock water productivity in crop-livestock systems of sub-Saharan Africa: synthesis. The Rangeland Journal 31: 169178.CrossRefGoogle Scholar
Anderson, J.M., and Ingram, J. S. L. (1993). Tropical Soil biology and Fertility: A Handbook of Methods. Wallingford, UK: CAB International.Google Scholar
Bekunda, M. (1999). Farmers' response to soil fertility decline in banana-based cropping systems of Uganda. Managing African Soils No. 4. International Institute for Environment and Development, London.Google Scholar
Berry, L. (2003). Land degradation in Ethiopia: Its extent and impact. Commisioned paper by the GM and WP support. Available from ftp://ftp.fao.org/agl/agll/ladadocs/ETHIOPIA_LD_CASE_STUDIES.docGoogle Scholar
Bossio, D., William, C. W., Geheb, K., Van Lynden, G. and Mati, B. (2007). Conserving land and protecting water. In Water for Food, Water for Life: A Comprehensive Assessment of Water Management in Agriculture, 551583 (Ed. Molden, D.) London: Earthscan.Google Scholar
Buerkert, A., Bationo, A. and Dossa, K. (2000). Mechanisms of residue mulch-induced cereal growth increases in West Africa. Soil Science Society of America. Journal 64:346358.CrossRefGoogle Scholar
Elias, S., Morse, S. and Belshaw, D. G. R. (1998). Nitrogen and phosphorus balances of Kindo Koisha farms in Southern Ethiopia. Agriculture, Ecosystems and Environment 71:93113.CrossRefGoogle Scholar
Fatondji, D., Martius, C., Bielders, C. L., Vlek, P. L. G, Bationo, A. and Gerard, B. (2007). Effect of planting technique and amendment type on pearl millet yield, nutrient uptake and water use on degraded land in Niger. In Improving Human Welfare and Environmental Conservation by Empowering Farmers to Combat Soil Fertility Degradation, 179193 (Ed. Bationo, A.). African Soils Network, Springer Verlag.Google Scholar
FAO (1998). Crop evapotranspiration – guidelines for computing crop water requirements. FAO, Rome.Google Scholar
FAO (2005). Local climate estimator (New LockClim 1.06). FAO, Rome.Google Scholar
Hassen, A. (1996). Improved traditional planting pits in the Tahoua department, Niger. An example of rapid adoption by farmers. In Sustaining the soil. Indigenous soil and Water Conservation in Africa, 5661 (Eds Reij, C., Scoones, I. and Toulmin, C.). London: Earthscan.Google Scholar
Jandel Scientific Software (1994). Sigma Stat Statistical Software for Windows. Jandel, San Rafael, CA.Google Scholar
Rockstrom, J. and de Rouw, A. (1997). Water, nutrients and slope position in on-farm pearl millet cultivation in the Sahel. Plant and Soil 195: 311327.CrossRefGoogle Scholar
Roose, E. and Barthès, B. (2001). Organic matter management for soil conservation and productivity restoration in Africa: a contribution from Francophone research. Nutrient Cycling in Agroecosystems 61:12.CrossRefGoogle Scholar
Roose, E., Kabore, V. and Guenat, C. (1999). Zai practice: a West African traditional rehabilitation system for semiarid degraded lands, a case study in Burkina Faso. Arid Soil Research and Rehabilitation 13: 343355.CrossRefGoogle Scholar
Smaling, E. M. A., Stoorvogel, J. J. and Windmeijer, P. N. (1993). Calculating soil nutrient balances in Africa at different scales II. District scale. Fertility Research 35: 237250.CrossRefGoogle Scholar
Soil Conservation Research Program (SCRP) (1996). Data Base Report (1982–1993), Series II: Gununo Research Unit. University of Berne, Berne.Google Scholar
Stoorvogel, J. J. and Smaling, E. M. A. (1990). Assessment of soil nutrient depletion in sub-Saharan Africa 1983–2000. Report 28. The Winand Staring Centre for Integrated Land, Soil and Water Research (SC-DLO), Wageningen.Google Scholar
Vanlauwe, B., Tittonell, P. and Mukalama, J. (2007). Within soil fertility gradients affect response of maize to fertilizer application in western Kenya. Nutrient Cycling in Agroecosystems 76:23.CrossRefGoogle Scholar
Vanlauwe, B., Aihou, K., Houngnandan, P., Diels, J., Sanginga, N. and Merckx, R. (2001). Nitrogen management in ‘adequate’ input maize-based agriculture in the derived savanna benchmark zone of Benin Republic. Plant and Soil 228:6171.CrossRefGoogle Scholar