People consume a lot of food to meet their daily nutritional and energy needs. As a result of agricultural activities to grow fruit, vegetables, and meat products, chemical pollution, excessive water consumption, and biodiversity loss occur. In addition to environmental, social, and economic impacts, agriculture also causes climate change to a large extent.
82–58% of greenhouse gas emissions from the food supply chain are caused directly, and 24% are caused by land use change. Most of the energy required for agricultural activities is obtained by burning fossil fuels, which release CO2 into the atmosphere.
Apart from organic fertilizers of animal and plant origin, farmers often use artificial fertilizers containing certain chemical nutrients to help plants grow larger, stronger, and faster. Although artificial fertilizers are useful, the gases released during their production constitute 1.4% of global greenhouse gas emissions.
With excessive use of fertilizers and irrigation of the soil, these fertilizers dissolve in water and are transported to water resources such as rivers and lakes. Algae in the water multiply uncontrollably with the nutrients in the fertilizer mixed into the water, causing an algal bloom.
That’s why the water appears green. When overgrown algae die, they are broken down by decomposer organisms and consume too much oxygen in the water, which can lead to fish deaths and a decrease in biodiversity.
Trees in forests are cut or burned to open agricultural land over a long period of time, used as pasture land, etc. The decrease in forest areas through processes such as this causes deforestation. The decrease in the proportion of forest areas increases the greenhouse effect.
Nutrients are transferred from one living thing to another through the food chain. During this transfer, some chemical substances are transferred to the bodies of living things and accumulate. This situation is called bioaccumulation. Radioactive substances, heavy metals, and poisons accumulate in the bodies of plants and animals and reach humans at the top of the food chain. These substances, which accumulate in the bodies of living things, cause microorganisms, birds, other organisms, and humans to become poisoned, ill, and die.