Welcome to International Network for Natural Sciences | INNSpub

Study of agronomic activities at the Kalimbeza rice project Namibia and the implication for sustainable productivity of the rice soil

Research Paper | May 1, 2017

| Download 13

V. Hepute, J. Abah

Key Words:

Int. J. Biosci.10( 5), 128-138, May 2017

DOI: http://dx.doi.org/10.12692/ijb/10.5.128-138


IJB 2017 [Generate Certificate]


In order to design sustainable management of the Kalimbeza rice project soil, it is expedient to assess the sustainability implication of the current agronomic activities which has the potential to threaten long term productivity of the rice soils. First, structured questionnaires were used to collect data from 10 field workers based on their memory recall of the different agronomic activities carried out at the rice project. Furthermore, soil samples were collected from the Kalimbeza rice soil at two depths: 0-15cm and 15-30cm for analyses of the soil properties. A fallow land of more than 10 years was also sampled at the same soil depths and analysed as control. The results obtained from the questionnaires responses revealed that chemical fertilizers are frequently used to improve the rice soil fertility but the fertilizers were applied without prior soil analysis to ascertain the nutrients status. It was also revealed that rice mono-cropping system is solely practiced, coupled with maximum harvesting as rice residues were used to produce livestock feed and not left to decay into the soil. T-test (paired sample mean, p < 0.05) analysis of the soil properties revealed that the rice soil has significantly lower levels of: total nitrogen, phosphorus, organic carbon, and cation exchange capacity than the control soil. Rice mono-cropping and maximum harvesting practiced at the Kalimbeza rice project could affect recovery capacity of the rice soil and present adverse implications for its sustainable productivity over long period. Therefore, it is recommended that crop rotation, leaving rice residues to decay and improve the soil structure, and applying chemical fertilizers after pre-determined site-specific properties should form part of the agronomic activities.


Copyright © 2017
By Authors and International Network for
Natural Sciences (INNSPUB)
This article is published under the terms of the Creative
Commons Attribution Liscense 4.0

Study of agronomic activities at the Kalimbeza rice project Namibia and the implication for sustainable productivity of the rice soil

Anon. 1995. Sustainable Agriculture and the Law, Directorate of Agricultural Information, Pretoria, South Africa.

Aondoaka SC, Agbakuru PC.  2012. An assessment of land suitability for rice cultivation in Dobi, Gwagwalada Area Council, Nigeria, Ethiopian Journal of Environmental Studies and Management 5 (4), 444 – 451, http://dx.doi.org/10.4314/ejesm.v5i4.S2.

Bi L, Xia J, Liu K, Li D, Yu X. 2014. Effects of long-term chemical fertilization on trends of rice yield and nutrients use efficiency under double rice cultivation in subtropical China, Plant, Soil and Environment 60(12), 537–543.

Bremner JM, Mulvaney CS. 1982. “Total nitrogen”, In: A.L. Page, R.H. Miller and D.R. Keeny, (Eds.), methods of soil analysis, American Society of Agronomy and Soil Science Society of America, Madison, 1119-1123.

Clark RB, Baligar VC. 2000. Acidic and alkaline soil constraints on plant mineral nutrition. In: R.E. Wilkinson (ed.) Plant-Environment Interactions. Marcel Dekker Inc, New York, 133-177 P.

Country Pilot Partnership in Namibia (CPP).  2005. Integrated sustainable land management, Global Environment Facility, Namibia.

Doran JW, Sarrantonio M, Liebig M. 1996. Soil health and sustainability. In: Sparks, D.L. (Ed.), Advances in Agronomy, Academic Press, San Diego, 56, 1-54.

FAO. 2006. Report of the International Rice Commission-Twenty-First Session Rome: Food and Agriculture Organization.

Gangwar B, Ram B. 2005. Effect of crop diversification on productivity and profitability of rice (Oryza sativa)-wheat (Triticum aestivum) system. Indian Journal of Agricultural Sciences, 75 (7), 435-438.

Gee GW, Bauder JW. 1986. Particle size analysis. In: Klute, A (Ed). Methods of soil analysis “Tropical and mineralogical methods. Agronomy, American Society of Agronomy, Madison, Part 1.Wisconsin. 383-411 p.

Gelman F, Binstock R, Halicz L. 2011. Application of the Walkley-Black titration for organic carbon quantification in organic rich sedimentary rocks, Report GSI/13/2011, Jerusalem, www.gsi.gov.il/_uploads/ftp/GsiReport/2011/Gelman-Faina-GSI-13-2011.pdf, Accessed: 09 April, 2015.

Hossain M. 1998. Sustaining food security in Asia economic, social and political aspects. In Dowling NG; SM Greenfield and KS Fischer (Eds), Sustainability of rice in the global food system. Manila (Philippines): International Rice Research Institute 19-43.

IITA. 1979. Selected methods for soil and plant analysis of the International Institute for Tropical Agriculture. IITA, Ibadan.

International Plant Nutrition Institute (IPNI), 2013.  Soil sampling,. Mosaic Company. crop nutrition.com

International Rice Research Institutes (IRRI), 2015. New UN-supported sustainability standard sets global environmental and social benchmark for responsible rice cultivation, Bangkok

Isitekhale HHE, Aboh SI, Ekhomen FE. 2014. Soil suitability evaluation for rice and sugarcane in lowland soils of Anegbette. The International Journal of Engineering and Science 3(5), 54-62.

John PS, George M, Jacob R. 2001. Nutrient mining in agro-climatic zones of Kerala. Fertilizer News, 46, 45-57.

Kabir H. 1999. Sustainability of Intensive Rice Production Threatened. ILEIA Newsletter, 14 -15 P.

Kanyomeka L. 2007. Rice cultivation in seasonal wetlands, Oshanas, and the Zambezi river plains of northern Namibia,  Ministry of Agriculture Water and Forestry, Namibia.

Lal R. 2009. Crop residues and soil carbon, carbon management and sequestration centre, Ohio State University, USA.

Marx ES, Hart J, Stevens RG. 1999. Soil test interpretation guide, Oregon State University, Accessed: 23 April, 2015. http://extension.oregonstate.edu/gilliam/sites/default/files/Soil_Test_Interpretation_Guide_EC1478.pdf,

Neeson R, Koenig T, Mudford E. 2005. Organic rice production: improving system sustainability, Rice Cooperative Research Centre final research report P2107FR06/05, NSW Department of Primary Industries, Yanco

Najim MMM, Lee TS, Haque MA, Esham M. 2007 Sustainability of Rice Production: A Malaysian Perspective. The Journal of Agricultural Sciences 3: 1-12, http://doi.org/10.4038/jas.v3i1.8138.

Nwilene FE, Oikeh SO, Agunbiade TA, Oladimeji O, Ajayi O, Sié M, Gregorio GB, Togola A, Touré AD. 2008. Growing lowland rice: a production handbook, Africa Rice Centre (WARDA).

Primavesi A. 1990. Soil life and chemical fertilisers. ILEIA Newsletter. 6,1-2.

Ratnayake RMC, Chinthaka BM, Balasooriya P. 2011. Sustainable rice production: a case study on performance evaluation of a seeder, Management and Production Engineering Review, 2(4), 50–56.

Rigby D, Cáceres DM. 2001. Organic farming and the sustainability of agricultural systems, Agricultural Systems, 68, 21-40, http://doi.org/10.1016/S0308-521X(00)00060-3

Rokonuzzaman M. 2012. Farmers’ perception on environment impact of rice monoculture in Bangladesh, Indian Research Journal of Extension Education, 12, 15-20.

Roy R, Chan NW, Rainis R. 2014 Rice farming sustainability assessment in Bangladesh, Sustainability Science 9, 31-44, http://dx.doi.org/10.1007/s11625-013-0234-4

Sanchez PA. 2010. Tripling crop yields in tropical Africa. Nature Geo-Science; 3, 299-300.

Shukla AK, Sharma SK, Tiwari R. 2005. Nutrient depletion in the rice-wheat cropping system of the Indo-Gangetic plains, Better Crops, 89, 28–31.

Singha K. 2013. Growth of paddy production in India’s north eastern region: A case of Assam. Anvesak, 42, 193-206.

UNU-IAS. 2008. Environment for Africa Development: A Sustainable Future through Science and Technology, UNU-IAS Report

USDA. 2004. Natural resources conservation service: soil survey laboratory methods manual. Soil survey investigation report no. 42 version 4.0. Natural Resources Conservation Service. 700 P.

Wanyama I, Ochwoh VA, Nankya E, Van Asten PJA. 2015. Optimisation of major nutrients (N, P and K) for lowland rice production in eastern Uganda, International Journal of Agronomy and Agricultural Research, 7 (2), 218-227.

Yan DZ, Wang DJ, Yang LZ. 2007. Long-term effect of chemical fertilizer, straw, and manure on labile organic matter fractions in a paddy soil. Biology and Fertility of Soils, 44, 93–101. http://dx.doi.org/10.1007/s00374-007-0183-0

Zhang, XP, Fang HJ, Yang X. 2005. No-till and hand hoeing impacts on carbon dioxide emissions from a silt loam in northeast China. Communication in Soil Science and Plant Analysis, 36,1041-1045, http://dx.doi.org/10.1081/CSS-200050489

Zhang Q, Wang G. 2005. Studies on nutrient uptake of rice and characteristics of soil microorganisms in a long-term fertilization experiments for irrigated rice, Journal of Zhejang University, Science 6B(2), 147- 154, http://dx.doi.org/10.1631/jzus.2005.B0147