Introduction
Maize is the third most important crop in the world after rice and wheat. Around half of world’s maize is grown in developing countries such as South Africa. In these countries maize is mainly a staple food and the maize stalks provide food for farm animals during the dry season. In Sub Saharan Africa, an estimated 50% of the population relies on maize to provide for their basic calories where it is used in an array of porridges, pastes, grits and beer (Centre for Environmental Economics and Policy in Africa (CEEPA), 2006). Green maize is also consumed as a meal, after dry spells, by roasting, boiling or baking. However this important crop is decreasing in yields in most regions of the world. In Africa, yields have declined by around 1.0t/ha according to Food and Agricultural Organization (FAO) (Parry, et al, 2004), this is due to the effects of climate change. In South Africa an average rainfall of 500mm is received annually meaning that the country is relatively dry. Moreover, more than a million people directly depend on agriculture for their livelihood and other countries in the region depend on the maize produced in South Africa.
Maize production in South Africa
Maize is a staple food in South Africa where it contributes an average of 71% of all grains produced. Maize farming covers 58% of the crop area in South Africa and 60% of this is in drier areas of the country. In 2000, 3205 hectares of land was planted with maize, which was an increase from the previous year’s 2905 hectares. Yields increased by an estimate of 8.3 and 8.9 million tones according to (Turple et al, 2002) in the same year. In the year 1999, maize production alone fetched R 4966 million. All this shows the important contribution of maize production to the country’s economy.
In South Africa maize is grown in two regions, that is, the western belt which is drier of the two regions and consists of the western Free State and North-West provinces and eastern zone which has a higher moisture and production. The eastern region consists of eastern Free State, Gauteng, Mpumalanga and KwaZulu-Natal provinces (CEEPA, 2006).
Climate change and maize production in South Africa
Maize cropping environment in South Africa is characterized by intra-seasonal and inter-annual variability of rainfall. Maize production has adopted an upward trend from 1951 to 1981 which was followed by a marked decrease in recent years (State of the environment.com). The upward trend can be attributed to various factors such as introduction of high yielding cultivars, advances in fertilizer use, better weed and pest control methods and progress in management practices. The decrease in yields can be attributed to climatic change, which has increased variability in seasonal rainfall amounts. This has created a high risk situation for both commercial and subsistence production (Ofori & Kyei-Baffour, 2006).
The situation is made worse by the anticipated global climate change linked with greenhouse effect. There is general consensus that such a change in climate will result in increased frequency of droughts and higher spatial variability in rainfall. Rainfall is projected to decrease by 5% to 10% accompanied by temperature rise of between 10C and 30C (Mearns & Norton, 2010). However, increased temperature and carbon dioxide level are projected to shorten the growth development time of maize which in turn will expose maize to environmental stress such as short drought periods and irregular weather during pollination. Another stress is that maize crop goes through the most vital reproduction stage in a shortened period (CCEPA, 2006).
Climate change has the likelihood of affecting crop production on a large scale by causing spatial shifts in agricultural areas and changes in food production, supplies, distribution, inter-regional dependence and international trade (Du Toit et al, 1999).
Adaptation measures
In order to reduce crop vulnerability to drier climate scenarios at the regional level, the growing regions should introduce irrigation to maintain a normal water demand for the crop. This however may bring problems as water resources may not be available in the dry areas in addition to financial constraints to small scale growers (Du Toit et al, 1999).
At an individual level, farmers can adopt more water conserving methods of farming such as mulchs, water harvesting techniques. These will suite some sites and will depend on the level of knowledge and expertise of the farmers. This can be supplemented with an irrigation system that will provide water at the most critical periods. However financial resources again become a hindrance to this method of adaptation (Jones & Thorton, 2003).
The government should also support grower-based measures of adaptation by increasing extension education in efficient use of water resources and funding of irrigation projects. The government can also engage agricultural scientists to develop more drought resistant maize cultivars adapted to the varying rainfall patterns. The government should also sponsor climate prediction program to assess crop feasibility in almost “real time”. Experts in this program prepare and produce reports on crop development during the season and predict the challenges ahead for growers. This will evaluate the best responses to climatic changes and events such as the El Nino and La Nina (Du Toit et al, 1999).
Conclusion
Maize is an important crop in the world and especially in South Africa. However, it is declining in production which is attributed to climatic changes which have affected seasonal rainfall variability. Individual farmers, government and other stakeholders should take adaptation measures to help the country cope with the anticipated global climatic changes such as more efficient water conservation methods and development of drought resistant maize cultivars among others.
Reference List
Centre for Environmental Economics and Policy in Africa (CEEPA). (2006). Climate Change and African Agriculture, A policy Note No. 28. Web.
Du Toit, A. S., Prinsloo, M. A., Durand, W. & Kiker, G. (1999). Vulnerability of Maize Production to Climate Change and Adaptation Assessment in South Africa. A Report. Web.
Jones, P. G. & Thorton, P. K. ( 2003). The Potential Impacts of Climate Change on Maize Production in Africa and Latin America in 2055. Global EnvironmentalChange 13, p. 1-59. Web.
Mearns, R & Norton, A. eds. (2010). Social Dimensions of Climate Change: Equity and Vulnerability in a Warming World. World Bank.
Ofori, E & Kyei-Baffour, N. (2006). Agrometerology and Maize Production. Web.
Parry, M. L., Rosenzweig, C., Iglesias, A., Livermore, M. & Fischer, G. (2004). Effects of Climate Change on Global Food Production Under SRES Emissions and Socio economic Scenarios. Global Environmental Change Vol. 14, p. 53-67.
State of the environment.com. Effects of Climate Change. Web.
Turple, J., Winkler, H., Spalding-Fecher, R. & Midgley, G. (2002). Economic Impacts of Climate Change in South Africa: A Preliminary Analysis of Unmitigated Damage Costs. A Report. Web.