As we move into a time in which floods, frosts, windstorms and droughts happen more frequently with the accelerated change of our climate, the pests and plant diseases which blight our crops will also transform.
Shifting climates and re-occuring extreme weather events will cause pests to emerge in new areas, alter predator-prey relationships, and increase the threat to public health and food security as humans respond by using heavier doses of pesticides.
Insects have adapted to nearly every habitat on Earth. They can be found in jungles, deserts, swamps, the arctic and even in incredibly volatile environments such as pools of crude petroleum. According to a report released by the Food and Agriculture Organization (FAO) on insect damage to crops, “Insects are undoubtedly the most adaptable form of life as their total numbers far exceed that of any other animal category.”
When considering the affects of climate change on insect populations, it is important first to understand that not all types of insects are harmful to humans or agriculture. For instance, some insect species are predators to insects that we consider pests, while other beneficial species can be pollinators, composters which enrich the soil, or produce highly valued commodities such as silk or honey.
Each insect species will be affected differently as the Earth’s climate changes. The risk factor of this change is so high because, in the worst case scenario, it may damage populations of those insects we find beneficial while increasing populations of those which blight our crops or carry human and animal diseases.
For instance, our crops have already struggled with the loss of bees, which have starved in times of drought or during extended periods of heavy rainfall, during which they were unable to leave their hives. Meanwhile, the bluetongue virus, a grotesque infection of ruminants, has been able to transcend its confines in southern Europe, born by booming midge populations. These midges have increasingly migrated to northern Europe, attracted to its weather which has become increasingly warmer since 1998.
Frequent, extreme weather events will not just affect pests but also the predators which keep their populations in check. Harsh weather conditions may cause predators to die off or migrate to a more inhabitable climate. Without these predators, pests that are unaffected by the weather or who emerge after it has cleared have free range over our crops.
Predator-prey relationships have already been altered and even discouraged by our current monoculture-based agricultural systems. Often, farmers choose to plant crops that are unsuited for the climate and thus are less resilient in the face of pest infestations. These crops only survive through the extensive use of petrochemical based pesticides, which farmers use as a crutch rather than choose climate appropriate crops or create an environment which naturally incorporates pest predators.
Pesticides and GE crops
As pests and weeds become more prevalent in certain areas due to climate change, farmers will resort to using more pesticides and herbicides. This practice is detrimental to the environment and human health for several reasons. First, larger quantities of pesticides means a larger amount of greenhouse gasses emitted to transport them from manufacturer to farm. This act in itself further propels the climate to change at faster rate.
Second, the increased use of pesticides poses a threat to human health, not only to the workers who apply the chemicals to our crops, but also to the consumers who eat the resulting produce. The threat to human health is most prevalent amongst poor rural workers who cannot afford to use less toxic chemicals or do not own the proper equipment to apply them safely.
Lastly, the overuse of pesticides can lead to developed resistance and the evolution of what are often referred to in the media as “superbugs.”
Increased pest populations will also cause farmers to resort to using more genetically engineered (GE) plant varieties which are modified to be “pest-resistant.” Such is the genetically modified Bt corn, which on top of its safety for human consumption being widely questioned, has already resulted in the evolution of resistant insects.
Food security at risk
According to the FAO, pests, weeds and plant diseases cause the loss of over 40 percent of the world’s food supply. Developing countries in particular will be most vulnerable to the effects of increased pests and diseases, as a large portion of their populations are rural farmers whose subsistence is dependent on agricultural production. Not only will poor crop yields affect rural farmers economically, but for many, a large portion of their diet comes directly from their own fields.
At present, our food security is highly dependent on access to food through international trade. This will be greatly impacted as pests and plant diseases reduce crop yields—especially of staple crops such as corn, wheat, soy, etc.—resulting in price increases and export bans. Furthermore, what crops are available for international trade will be subject to a higher level of inspection, thus increasing importation costs.
Resilience through polyculture and local sourcing
The increasing frequency of extreme weather events will require a more adaptable approach to food cultivation. An important step for consumers to make towards building resilience within our food systems is to support local, organically cultivated farms. Such farms integrate a diverse range of plant and animal life to produce stronger ecosystems that naturally attract pest predators. On the farmer’s behalf, it is essential for them to cultivate plants which are naturally pest resistant as well as more adaptable to climate change. Many small farms that are organically cultivated are not certified organic, so it is important to get to know your local producers and their methods.
Choosing to source your food from local producers whose farming practices you are acquainted with is the best way of ensuring that you have a source of safe, clean food in a time when our food system may be strained. Growing your own food, both at a personal and a communal level, will also be essential to adapting to the affects of climate change. Blocks on food imports to ensure greater pest control along with damages to domestic monocultural and pesticide reliant crops will challenge the general consensus that food is endlessly available. When this happens, what we will be left with is the food that is grown in our own regions and communities.