Climate change is the long-term or permanent shift either upwards or downwards of average climatic condition for instance temperature, rainfall, wind, humidity. Potato production depends on rainfall and temperature. The variability of these key parameters due climate change will affect conditions necessary to cultivate potato. Extreme weather events such as high rainfall, temperatures and humidity, flooding and droughts increases risks in potato growing areas. High rainfall intensities might increase land degradation through landslides, mud flows, soil erosion, high incidences of diseases such as tuber rots and fungal diseases as well as destruction of suitable productive lands, hence the risk of decreasing acreage of land under potato production. Drought will accelerate soil moisture loss, enhance land degradation through destruction of soil structure, reduction in soil fertility through high rate of soil organic matter decomposition (low soil organic carbon) and erosion by wind, acidity and alkalinity as well as more pests leading to crop failure and low and /or productivity.
Extreme high temperatures may trigger emerging pests, mutation of pests and reduced life cycles leading to intensive use of pesticides to protect the crop from destruction. This may cause pesticide resistance by pests and compromise on the quality of potato tubers harvested therefore directly impacting on food safety and food security. In addition, high temperatures poses a challenge in potato storage due to high postharvest losses as result of spoilage and deterioration of quality of produce. On the flip side, dormancy period may be shortened especially in varieties that normally have long dormancy periods such as Unica.
Changing weather conditions affects potato marketing system directly and indirectly. Low rainfall or failed rainfall lead to low yields or 100% crop loss therefore affecting the market prices. Market prices are dependent on supply and demand forces. When supply is low, market prices are very high. Extended rainfall periods and high intensity rains disrupt the supply of potatoes to the market due to damage to roads and infrastructure and physical assets. For instance, daily rainfall of at least 45 mm for three days accelerates road damage which leads to market inaccessibility and therefore high postharvest losses and loss of household incomes.
Currently, farmers use conventional potato production management practices such as use of inorganic fertilizers and inorganic pesticides to improve soil fertility and control pests and diseases to produce potatoes. In addition mechanization is being promoted for efficiency in production thus some farmers use tractors for farm and post-harvest management practices. These operations generate a significant amount of land-use greenhouse gases (GHGs) especially carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4), making agriculture one of the highest emitters of GHGs. Like any other agriculture production system, potato production faces three major intertwined challenges (low productivity, climate vulnerability and GHGs generations) that require a ‘triple win’ approach to address this challenges. The triple win approach includes sustainable productivity, adaptation to climate change and mitigation and/or removal of GHGs emissions which can be delivered through Climate Resilient Agriculture (CRA).
Extreme weather events such as drought (left) and floods( right) result in huge potato losses.
Photo courtesy of freshplaza.com and majorcadailybulletin.com
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