Nitrogen Distribution Model: A Farmer and Farm-Centred Model to Monitor N Movement in the Soil

J. Mthandi^1*, F. C. Kahimba¹, A. K. P. R. Tarimo¹, B. A. Salim¹, M. W. Lowole²

¹Department of Agri. Eng. and Land Planning, Sokoine University of Agriculture, Morogoro, Tanzania.
²Department of Crop Science, Bunda College of Agriculture, Lilongwe, Malawi.

DOI: 10.4236/jwarp.2014.616141                

Abstract

There are several models that monitor movement of nitrogen in the soil. Most of these models have not been widely used in southern Africa because of sophisticated equipment required to collect data and the data needed to run the model are intensive. Nitrogen Distribution Model (NDM) has been developed to ensure that it responds to increasing need of managing nitrogen in agricultural systems characterized by smallholder farmers who do not have adequate resources to collect intensive data for modeling. NDM has parameters that are explicit and mostly intuitive and maintains good balance of simplicity and robustness. With the nature of smallholder farming in Malawi where over 85% of population are rural-based smallholder farmers, the model has also be designed so that it can acts as database to keep track of farmers and farms so that were given farm-specific nitrogen and water management advice.

Keywords

Nitrogen Distribution Model, Modeling, Water, Nitrogen

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Hodge, A. (2008) The Plastic Plant: Root Responses to Heterogeneous Supplies of Nutrients. New Phytologist, 162, 9-24.
[2]	Buresh, R.J., Sanchez, P.A. and Calhoun, F., Eds. (1997) Replenishing Soil Fertility in Africa. Soil Society of America, Special Publication No. 51. Madison.
[3]	Bauder, T.A. Waskom, R.M. and Andales, A. (2008) Nitrogen and Irrigation Management No. 0.514 Colorado State University Extension. 3/99. Revised 6/08. www.ext.colostate.edu
[4]	Haefner, J.W. (1996) Modeling Biological Systems: Principles and Applications. Utah State University. Chapman and Hall. International Thomson Publishing. http://dx.doi.org/10.1007/978-1-4615-4119-6
[5]	O’Leary, M., Rehm, G. and Schmitt, M. (2014) Understanding Nitrogen in Soils. http://www.extension.umn.edu/agriculture/nutrient-management/nitrogen/ understanding-nitrogen-in-soils/
[6]	Jury, W.A., Gardner, W.R. and Gardner, W.H. (1991) Soil Physics. 5th Edition, John Wiley and Sons, New York.
[7]	Van Genuchten, M.Th., Leij, F.J. and Yates, S.R. (1991) The RETC Code for Quantifying the Hydraulic Functions of Unsaturated Soils. R. S. Kerr Environmental Research Laboratory, Ada.
[8]	Vitousek, P.M., Hattenschwiler, S., Olander, L. and Allison, S. (2002) Nitrogen and Nature. Ambio., 31, 97-101.
[9]	Nielsen, D.R., van Genuchten, M.Th. and Biggar, J.W. (1986) Water Flow and Solute Transport Processes in the Unsaturated Zone. Water Resources Research, 22, 89-108. http://dx.doi.org/10.1029/WR022i09Sp0089S
[10]	Mulla, D.J. and Strock, J.S. (2008) Nitrogen Transport Processes in Soil. In: Schepers, J.S. and Raun, W.R., Eds., Nitrogen in Agricultural Systems, Agronomy Monograph 49. American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, Madison.
[11]	Berner, R.A. (1971) Principles of Chemical Sedimentology. McGraw-Hill, Inc., New York.
[12]	Drever, J.I. (1982) The Geochemistry of Natural Waters. Prentice-Hall, Inc., Englewood Cliffs.
[13]	Shackelford, C.D. and Daniel, D.E (1991) Laboratory Diffusion Testing for Waste Disposal—A Review. Contaminant Hydro., 7.
[14]	Igbadun, H.E. (2006) Evaluation of Irrigation Scheduling Strategies for Improving Water Productivity: Computer-Based Simulation Model Approach. Ph.D. Dissertation, Sokoine University of Agriculture, Morogoro.