Abel Kivelia Kaaya (PhD)

Name:            Abel Kivelia Kaaya (PhD)

Contacts:      Mobile:            +255 788 444530

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Dr. Abel Kivelia Kaaya is a soil scientist and pedologist with vast experience in research and training in the areas of soil morphology, soil genesis, soil classification, soil survey and land evaluation. He is also involved in consultancy and outreach activities on the themes mentioned above as well as soil organic carbon monitoring. Dr. Kaaya’s specialization is pedology for soil/land resources’ characterization and assessment. He has over 30 years of experience in university teaching, research, consultancy and outreach in his area of specialization. Dr. Kaaya has authored numerous publications in peer-reviewed journals, conference proceedings, book chapters and extension manuals. He has also carried out various consultancies in the areas of pedological characterization for assessment of potentials for agricultural development as well as Soil organic carbon monitoring . He is a member of the Soil Science Society of East Africa, and was for some time a member of the International Soil Science Society (ISSS).


  • PhD (Soil Science) – 1998 - Agricultural University of Norway, Norway
  • MSc. (Agriculture) specializing in Soil Science – 1989 - Sokoine University of Agriculture, Tanzania
  • Postgraduate Diploma in Soil Science – 1986 - Agricultural University of Norway, Norway
  • BSc. (Agriculture) – 1984 - Sokoine University of Agriculture, Tanzania


  • Senior lecturer - July, 2005 to date
  • Lecturer - July, 1991 to June, 2005
  • Assistant Lecturer - July, 1987 to June, 1991
  • Tutorial Assistant - December, 1984 to June, 1987


Teaching both undergraduate and postgraduate students:

Undergraduate courses taught include:

  • Introductory Geology and Soil Formation,
  • Fundamentals of Soil Science,
  • Soil resources,
  • Land Evaluation and Land use planning,
  • Soil classification,
  • Management of natural resources and sustainable agriculture

Postgraduate courses include:

  • Soil micromorphology
  • Soil mineralogy
  • Soil genesis, survey and land evaluation
  • Soil resources of the tropics and subtropics


  • Conducts research in the field of soil science and related subjects, (soil science, agronomy, soil and water resource management and soil organic carbon mapping and monitoring)
  • Supervision of BSc Research Projects , MSc and PhD students Research works,
  • Consultancy, extension and outreach activities in the field of agriculture and related sciences (e.g. soil organic carbon mapping and monitoring).


Dr. Kaaya has experience in supervising postgraduate students’ research in areas of pedology including general soil fertility characterization, soil classification, soil survey and land evaluation.

PhD research supervision:

  1. Meki Chirwa (2012 – 2017), Improving Soil Productivity in Groundnut-Based Cropping Systems in Chisamba District, Zambia. Co- supervisor, PhD (Soil & Water management) at Sokoine University of Agriculture – candidate graduated in 2017
  2. Massawe, Boniface H. J. (2012 – 2015) Digital soil mapping and GIS-based land evaluation for rice production in Kilombero Valley, Tanzania – Co- supervisor, PhD (Soil Science) at Ohio State University, USA. Candidate graduated in 2015

MSc Research supervision:

  1. Ndare, Dennis Wambura (2017 – 2018) Effect of Different Types of Fertilizer on the Growth, Yield and Quality of Cassava in Lake Zone, Tanzania. Candidate graduated in November 2019
  2. Lwiza, S. (2015 - 2016) Soil factors contributing to high levels of nitrates in drinking waters in Singida District, Tanzania - candidate graduated in 2016
  3. Andrea, P. (2014 - 2015) Potential of various Gypsum rocks from Tanzania as potential of ameliorating problem soils for agronomic uses – graduated in 2015
  4. Mbalila, Scola (2014 – 2015), Assessment of the potential of Siam weed (Chromolaena odorata) in enhancing soil fertility for crop production in Serengeti District, Tanzania. - Graduated in 2015
  5. Makoti, Clavery A.(2012 - 2013). Assessment of uranium levels in Vertisols and associated soils and its uptake by rice, maize and millet in Bahi District, Tanzania – MSc (Soil Science & land Management) at SUA. Candidate graduated in 2014.
  6. Kirsten, M. S. (2012 - 2013). The effect of land use changes to Soil Organic Carbon pools in Eastern Usambara mountains MSc research Dresden University Germany. Graduated in 2014. Candidate graduated in 2014.
  7. Mathew, L. (2002 - 2003) Comparative Assessment of land suitability evaluation based on land mapping units and Agroecological zones: A case study of Morogoro Rural District. M.Sc. (Soil Science & Land Management) dissertation, Sokoine University of Agriculture, Morogoro, Tanzania. Candidate graduated in 2003
  8. Hamad, H.S. (1991 - 1992) Characterization and soil fertility evaluation of three major rice growing areas of Zanzibar Island. .M.Sc. (Agric.) dissertation, Sokoine University of Agriculture, Morogoro, Tanzania. Candidate graduated in 1992.


  1. Kempen, B., Dalsgaard, S., Kaaya, A. K., Chamuya, N., Ruipérez-González, M., Pekkarinen, A. and Walsh, M. G. (2019). Mapping topsoil organic carbon concentrations and stocks for Tanzania, Geoderma, 337: 164–180.
  2. Massawe, B. H. J., K. Kaaya and B. K. Slater (2019). Involving small holder farmers in the agricultural land use planning process using Analytic Hierarchy Process in rice farming systems of Kilombero Valley, Tanzania. Afr. J. Agric. Res. 14(7): 395-405.
  3. Primitiva, A. M., Marwa, E. M. M. and Kaaya, A. K. (2018). Characterization of Selected Gypsites of Tanzania for Agricultural Use. International Journal of Plant & Soil Science, 23(4): 1-9.
  4. Massawe, B. H. J., Subburayalu, S. K., Kaaya, K., Winowiecki, L. and Slater, B. K. (2018). Mapping numerically classified soil taxa in Kilombero Valley, Tanzania, using machine learning. Geoderma, 311: 143-148.
  5. Chirwa, M., Mrema, J. P., Mtakwa, P. W., Kaaya, K., and Lungu, O. I. (2017). Yield Response of Groundnut (Arachis hypogaea L.) to Boron, Calcium, Nitrogen, Phosphorus and Potassium Fertilizer Application. Int. J. Soil Sci., 12 (1): 18-24.
  6. Chirwa, M., Mrema, J. P., Mtakwa, P. W., Kaaya, K., and Lungu, O. I., 2017. The Effect of Combining Calcium, Nitrogen and Phosphorus Fertilizer Application on Groundnut Yield in Smallholder Farmers' Sole Cropping System. Int. J. Curr. Res. Biosci. Plant Biol. 4(4), 83 – 91.
  7. Kirsten, M., Kaaya, A., Klinger, T. and Feger, K. (2016) Stocks of soil organic carbon in forest ecosystems of the Eastern Usambara Mountains, Tanzania. Catena 137: 651 – 659.
  8. Chirwa, M., Mrema, J. P., Mtakwa, P. W., Kaaya, K., and Lungu, O. I. (2016). Evaluation of Soil Fertility Status and Land Suitability for Smallholder Farmers’ Groundnut and Maize Production in Chisamba District, Zambia. International Journal of Plant & Soil Science, 10(4): 1-18.
  9. Massawe, B. H. J., Slater, B. K., Subburayalu, S. K., Kaaya, A. K. and Winowiecki, L. (2016) Updating legacy soil maps for climate resilient agriculture: A case study of Kilombero Valley, Tanzania. In Lal, D. Kraybill, D. O. Hansen, B. R. Singh, T. Msogoya and L. O. Eik (Eds.) Climate Change and Multi-Dimensional Sustainability in African Agriculture, pp. 345 – 364. Springer International Publishing AG 2016, New York. DOI 10.1007/978-3-319-41238-2-19.
  10. Chirwa, M., Mrema, J. P., Mtakwa, P. W., Kaaya, K., and Lungu, O. I., 2015. Smallholder farmers perceptions on groundnut (Arachis hypogaea L.) - based cropping systems: A case study of Chisamba District, Zambia. Journal of Agricultural Extension and Rural Development, 7(11): 298-307.
  11. Marwa, E.M.M., J.M. Mziray, B. Chove, and K. Kaaya (2014) Uranium contamination in drinking water and foodstuffs in Bahi District, Central Tanzania. Journal of Continuing Education and Extension, 5(2): 625-640.
  12. Mäkipää, R., J. Liski, S. Guendehou, R. Malimbwi and Kaaya. (2012). Soil carbon monitoring using surveys and modeling: General description and application in the United Republic of Tanzania. FAO Forestry Paper No.168. FAO, Rome, 61pp. ISBN 978-92-5-107271-4.
  13. Msanya, B. M., Kaaya, A. K., Araki, S., Otsuka, H. and Nyadzi, G.I. (2003). Pedological characteristics, general fertility and classification of some benchmark soils of Morogoro, Tanzania. African Journal of Science and Technology (AJST), Science and Engineering series 4(2): 101 – 112.
  14. Sørensen, R., Murray, A.S., Kaaya, A.K., and Kilasara, M. (2001). Stratigraphy and formation of a Late Pleistocene colluvial apron in Morogoro District, Central Tanzania. Palaecology of Africa and the Surrounding Islands, 27: 95 – 116.
  15. Kaaya, A.K., Msanya, B.M. and Mrema J.P. (1994). Soils and land evaluation of part of the Sokoine University of Agriculture farm (Tanzania) for some crops under rainfed conditions. African Study Monographs, 15(2): 97-118.


  1. Marwa, E.M.M., B. Chove, and K. Kaaya (2014) Risk of Uranium Contamination in Selected Agricultural Soils of Bahi District in Central Tanzania and its Transfer in Food Chains. Research Brochure, Sokoine University of Agriculture, Morogoro, Tanzania. 6 pp.
  2. Backman, B., Janhila, M., Kaaya, A., Karinen, T., Lindqvist, K., Marwa, E., Partanen, M. and Shine, Y. (2017). Geochemical Soil Atlas of Tanzania. Geological Survey of Tanzania, Dodoma.
  3. Vesa, L., R. E. Malimbwi, E. Tomppo, E. Zahabu, S. Maliondo, N. Chamuya, E. Nssoko, J. Otieno, G. Miceli, K. Kaaya and S. Dalsgaard. 2010. National Forestry Resources Monitoring and Assessment of Tanzania (NAFORMA) Field Manual: Biophysical survey. NAFORMA DOCUMENT: M01-2010. Forestry and Beekeeping Division, Ministry of Natural Resources and Tourism, The United Republic of Tanzania, Dar es Salaam.
  4. Kaaya, A.K. Soils of Mzula Village (Dodoma District) and their suitability for some selected crops under rain-fed conditions. Extension report prepared for Mzula Village land use planning and submitted to the Dodoma Land Use Management Project, Dodoma.