O Level Notes : Geography - Agriculture And Land Reform - Climate change and agriculture

Agriculture is the growing of crops and rearing of animals. This topic focuses on the effects of climate change on agriculture, mitigation and adaptation measures to effects of climate change, agriculture pests and diseases, urban agriculture andAgri business.

 CLIMATE CHANGEAND AGRICULTURE

There is a direct correlationship between climate change and agriculture. The gradual change in climate has adversely affected agricultural activities putting many nations at a higher risk of food insecurity. In most developing countries, the effects of climate change are very severe since they lack the necessary equipment and funding to curb the adverse effects of climate change and guarantee food security. Climate change refers to the drastic shift in average weather phenomena associated with an increase in global average temperatures in a given area over a few to many years. This phenomenon is also responsible for changes in sea level and ice mass loss in Greenland. 

Causes of climate change

Climate change is mainly caused by greenhouse gases emitted from industrial activities. The greenhouse gases include: carbon dioxide, nitrous oxide and methane. Once trapped in the lower atmosphere, they trap heat hence resulting in global warming.

 Continued destruction of forests to pave way for agriculture and settlement is also causing climate change. Cleared forests are later burnt thereby emitting carbon dioxide which adds on to the amount of other greenhouse gases in the lower atmosphere. 

Crop production in paddy fields is also another cause of climate change because their cultivation results in the emission of methane in the atmosphere. However, most agronomists are of the idea that agricultural production will mostly be affected by severe and not gradual changes in climatic trends. This is so because climate change avails time to all living organisms to adjust and adapt to the new living conditions. 

Climatic change is caused by high rates of emission of greenhouse gases, for example, chlorofluorocarbons are widely used in appliance such as refrigerators. If their use is not regulated, they damage the atmosphere by depleting the ozone layer as well as trapping heat in the atmosphere resulting in climate change.

Effects of climate change on agriculture 

Climate change has several effects on agricultural processes, however, it should be noted that agricultural production is differently affected from one ecological region to the other. In most marginal areas characterised by poor soils and limited 

Zimbabwe agro ecological regions

The map above shows that Zimbabwe is subdivided into different ecological regions which have different characteristics in climate and soil types. The effects of climate change in Zimbabwe are severe in regions four and five since these areas are naturally characterised by poor soils and limited rainfall. A further increase in temperatures makes these regions less productive. 

Climate change often leads to global warming which negatively affects agriculture by creating conditions which facilitate the multiplication of pests and insects. The pests and insects mainly affect crops like maize, wheat and soya beans, for example, research done in Japan indicated that beetles in the fields with increased carbon dioxide laid more eggs on the soya bean plants thereby putting the crop at a higher risk of being devastated by the pests. 

Agriculture is also affected by climate change because an increase in temperature often results in crop wilting hence crop failure. Moreso, the scourging heat destroys pastures putting livestock farmers at risk. Climate change also alters the developmental stages of pathogens and this affects crop and animal quality and quantity.

A series of drought ravaging parts of Africa, Southern Europe, the Middle East, South East Asia and some parts of America can be traced back to the effects of climate change as evidenced by an increase of levels of global warming. The effects of drought on agriculture is worsened by an increase in demand for water resource due to population growth being experienced worldwide. 

Climate change in Europe lead to crop failure hence a reduction in crop yields. The reduction in crop yields are mainly due to heat waves experienced which are directly linked to climate change. Falling crop yields also results in rise in food prices locally and globally thereby lowering living standards of the general populace.

Schneider et al (2009) projected that by the year 2100, global mean temperature will increase by at least 3 degrees Celsius which in turn will affect cereal production in most areas. Projections also suggest that there could be a larger increase in hunger occurrences by year 2080 if there are no global efforts put in place to curb the effects of climate change. 

Climate change has resulted in occurrence of El Nino in and beyond Zimbabwe. El Nino often results in floods which have negatively impacted on crop and animal

production and attainment of food security.

 Some of the effects of climate change on agriculture

Mitigation measures to climate change 

Although climate change has become a global problem, several measures can be put in place to curb the effects of climate change on agricultural productivity. Efforts should be made to regulate and reduce the amount of greenhouse gases emission into the atmosphere. Reduction in the amount of greenhouse gases emitted would lead to a decrease in the effects of climate change hence food security is guaranteed. 

There should be efforts made to create the necessary agricultural technologies and utilising them enable countries to adapt their agricultural systems to changing climates. Some of these technologies include the drip irrigation kits which are used to ensure effective watering of crops in areas with limited water sources.

Drip Irrigation as a way of mitigating against climate change

New varieties of seeds and new breeds of animals can be devised whose genetics should be altered to suite the prevailing conditions. Maize seed producers in Zimbabwe have embarked on this long journey to produce seeds capable of yielding much in the prevailing limited climatic conditions. To aid communal farmers comprehend maize varieties, they have incorporated animal names which are found locally, for example, elephant, zebra and hare. 

The government should develop and implement policies which restricts emission of greenhouse gases which pollute the air hence resulting in climate change.

These should be done to foster agricultural specialization according to agro ecological regions. Moreso, farmers should be educated on the best agricultural projects which suites their environments. 

Livestock farmers should identify and promote the adoption and cross breeding of indigenous livestock breeds that are tolerant to conditions created by climate change, for example, the hard Mashona breed is resistant to diseases and can survive on limited water. Adoption of conventions and protocols on climate change and global warming also help in fighting against effects of climate change.

 Drought resistent livestock

Challenges found in effects of climate change mitigation

Although efforts are being made to mitigate effects of climate change on agriculture in Zimbabwe, the country is still faced with several challenges and some of these include:

• Limited knowledge and capacity to respond to climate change by most communal farmers

• Limited resources and infrastructure to mitigate climate change.
• Inadequate funding and support for the development of agricultural technologies which can be utilized in the face of climate change.
• Limited empowerment of communities to access resources which helps them to maintain high yields in areas affected by climate change.
• people have little access to information relating to climate change