Agriculture And Climate Change

 

Agriculture refers to all the activities done in the process of raising livestock, planting crops and other types of farming. It refers to everything involved from start to finish, when the food is finally presented at the table.

Agriculture has been a part of human life for millennia, for both domestic consumption and as an economic activity.

Agriculture in all its forms takes up a third of the emissions that cause climate change. But unlike fossil fuels that can be done away with completely and substituted with renewables, agriculture is essential for human life and survival in terms of both food security and the economy. So, it can only be restructured to be less climate hazardous while still maintaining its purpose. Food security is both the ability to provide enough food, and food that is of satisfactory nutritional content.

The current way of doing agriculture is resource intensive, and is one of the reasons why a third of global soils are degraded.

Agriculture both causes and is affected by climate change.

The aim of climate action in agriculture is to cut emissions, increase resilience of agricultural systems to climate impacts and increase food production.

A wheat farm - Reuters

These triple goals are reliant on each other because action in one area should not negatively impact the other areas. Because emissions already in the atmosphere will continue to warm the climate and because natural climate systems take a long time to completely respond and react to stimuli, climate will continue to change, and this will as a matter of fact affect agricultural systems. Likewise, the population of the earth is projected to continue growing, and so the capacity of agriculture will have to reach its full potential in order to meet this dietary need.

The principal greenhouse gases produced in agriculture are methane, nitrous oxide and carbon dioxide.

Methane is naturally produced from the digestive system of cattle, which are kept for both dairy and beef purposes. Methane, a hydrocarbon, is released from decomposing manure and also from artificial fertilizers which contain nitrogen as a major component. Both of these are applied to soils to increase fertility.  It is also produced from rice farms, because the flooded soils only allow for anaerobic (without oxygen) breakdown of fertilizers which then release methane.

Methane is also produced from decomposing food waste in landfills.

Nitrous oxide is produced from decomposing manure that has no access to air. It is also produced from nitrogen based fertilizers which are broken down by nitrogen fixing bacteria in the soil. These synthetic fertilizers have another environmental threat in that they are washed into waterways and fertilize them (eutrophication), causing mass algae growth. This eventually depletes oxygen in the water and imperils marine life.

Carbon dioxide on the other hand is from other subsidiary activities that are not directly involved in plant growth. This includes the use of farm machinery that use fossil fuels, the manufacture of fossil fuel-based farm inputs (fertilizers) and the processing of food products along the chain, from harvest to table. Directly, the tilling of soil releases the stored carbon stocks in the soil.

Climate change on the other hand impacts agriculture because of erratic weather patterns. Also, droughts lower crop yields and affect plant growth, and floods and typhoons destroy farms and damage infrastructure. Heat waves also cause heat stress to animals and results in lowered yields and death.

Likewise, the nutritional content of crops especially in terms of protein and the dietary value of animal meat and dairy is greatly lowered. Pasture fed herds are particularly affected since the quality and quantity of animal feed is reduced because of climate change. This occurs when temperatures rise, and there is lower rainfall, the surface area of pasturelands decrease, the land is drying out. Also, increased levels of carbon in the atmosphere, without the accompanying conditions for optimum plant growth such as enough water cause plant yields to decline. Another scientific fact is that more carbon dioxide reduces nutritional content of all plants inclusive of foodcrops.

Certain food crops are also affected because as climate zones shift unpredictably, conditions needed for growth are also altered. For example, wheat and rice production is already altered globally because of increased CO2, less rain and hotter temperatures. It is important to note that these two food crops, together with maize feed around half of the world’s population.

Aquaculture or the fisheries sector, worth over 400 billion, is affected by climate change. Generally warmer waters which are also acidic are not optimal for aquatic life. The ocean and waterways absorb heat from the air and so serve to regulate climate. But as they do so, they become warmer, and this reduces their capacity to dissolve and store oxygen, which is essential to marine life. Additionally, some species of marine life like corals and shellfish need calcium from the water to form their body structure. Increasing amounts of dissolved carbon dioxide form carbonic acid, which directly reduces the ability of these organisms to make calcium carbonate and so affect survival rates and population numbers.

Also, certain species of fish need cool temperatures to breed, so the warmer the waters get, the more they migrate or die off. In short, their ability to reproduce is greatly affected. This has repercussions on the entire food chain, and is eventually felt in the sea food industry.

Thirdly, disease causing pathogens are directly aided by warmth, so as the waters grow hot, their area of occupation increases. They can now spread to other sea animals which were previously safe because they were outside the geographical area of infection.

All this serves to reduce the catch potential.

In similar ways, because of rising temperatures and more rainfall especially at the wrong times, the endemic range of plant diseases like maize lethal necrosis and pests is altered towards previously sheltered crop zones. All this negatively affects food crop production.

Moreover, this is dangerous because it leads to increased use of pesticides to manage crop pests. These inevitably make their way up the food chain and so endanger human health. Pesticides are synthetic chemicals that are not naturally occurring. They harm human health in several ways, including being carcinogenic.

Climate change affects the habitat and also the flowering and maturation times of crops, causing them to flower earlier but mature poorly. In other ways, the insects that facilitate pollination of crops are affected by changes in climate as well. This is particularly concerning because agriculture and therefore food yields would be non-existent without animal and insect pollination.

Additionally, agriculture and food security is indirectly affected by severe climate impacts such as drought or floods disrupting transport systems. This eventually affects not only human health, but the economy as well.

Solutions are in two major forms: cutting emissions from the sector and protecting from the harshest impacts of climate change.

In terms of cutting emissions, it means resorting to conservation agriculture, organic farming, mulching and other innovative methods like hydroponics. This also includes rotational farming and use of natural methods to increase soil fertility without harming climate.

Agroforestry, which is the growing of trees alongside other crops, is a veritable way to both promote agriculture and stop climate change. Trees have myriad benefits in farms. They produce healthy food in the form of fruits. Tree roots hold the soil together and stop erosion. They increase soil fertility because of leaves and branches forming humus. They provide fuel, and allow for the optimum percolation and retention of water in the soil. Also, they provide shade for other crops and so prevent heat stress and wilting. Trees also absorb carbon dioxide.

Use of renewable fuels instead of fossil fuels in farms is climate friendly.

To increase production, it is clear that we must irrigate as many acres of arable land in order to compensate for and reduce reliance on rain-fed agriculture. Additionally, crop species are being reexamined so that the best varieties can be grown for the changing climatic zones. This calls for more research and financial investment.  For example, the more than 41 drought tolerant and pest- resistant crop species developed by the Kenya(n) Plant Health Inspectorate Service.

We can pivot from animal based to plant based protein in order to reduce the carbon footprint of livestock keeping. Increased diversification of food sources is a solution.

For rice cultivation, it is recommended to drain and rewet the sections, rather than having them covered with water throughout. This would reduce the amount of methane released.

In  livestock keeping, better types of feed that are nutrient packed but lesser in terms of quantity could be used as alternatives to what is currently used. This means that more of animal products can be made with less of feed.

Food wastage is a major source of greenhouse gases emissions. If regarded as a country, it would be the third major national emitter globally.

It occurs as post-harvest losses, in the processing chain. Also, when food is rejected for flimsy reasons such as being misshapen and when perfectly good food is dumped in landfills in favor of fresher batches. Better methods of agricultural processing which enable the long term storage of food without spoilage is recommended.

In general, both climate change and agriculture are here to stay, and solving both requires cooperation and an integrated approach for climate health and dietary wellbeing.