Farmers' Role In Reducing Air Pollution

Agriculture is a significant contributor to air pollution, with farming practices accounting for around 93% of total ammonia emissions in the EU and 25% of the world's greenhouse gas emissions. However, farmers can play a crucial role in reducing air pollution by adopting certain sustainable practices. These include improving nutrient management techniques by applying fertilisers accurately and at the right time of year, using conservation buffers such as trees and shrubs to catch runoff, implementing conservation tillage to reduce soil erosion and compaction, and having a manure management plan to avoid spills and water contamination. By combining these practices with the use of alternative energy sources and efficient fertiliser use, farmers can significantly contribute to cleaner air and a healthier climate.

Improve nutrient management techniques

Farmers can improve nutrient management techniques by adopting practices that reduce nutrient loss and increase efficiency. This can be achieved through the following methods:

Right Source, Right Method, Right Rate, and Right Timing

Farmers should apply nutrients (fertilizer and manure) in the proper amount, at the right time of year, with the right method, and with the right placement. This includes selecting the right nutrient sources that best match the needs of the crop and soil while minimizing the site-specific risk of nutrient loss.

Injection and Incorporation

Getting nutrients below the surface of the soil and into the root zone of crops increases their ability to access the nutrients. Injection is one way to deliver them exactly where they are needed. Specific sites may require nutrients to be incorporated into the soil, not just broadcast on the surface, for plants to adequately access them and to reduce the risk of nutrient loss in runoff events.

Conservation Drainage Practices

Subsurface tile drainage is an important practice for managing water movement on and through many soils, especially in the Midwest. Strategies are needed to reduce nutrient loads while maintaining adequate drainage for crop production. Conservation drainage includes practices such as modifying drainage system design and operation, woodchip bioreactors, saturated buffers, and modifications to the drainage ditch system.

Year-Round Ground Cover

Planting cover crops or perennial species can prevent periods of bare ground on farm fields when the soil (and the nutrients it contains) are most susceptible to erosion and loss into waterways.

Field Buffers

Planting trees, shrubs, and grasses along the edges of fields, especially those bordering water bodies, can help prevent nutrient loss by absorbing or filtering out nutrients before they reach a water body.

Conservation Tillage

Reducing the frequency and intensity of tilling can improve soil health, reduce erosion, runoff, and soil compaction, and decrease the chance of nutrients reaching waterways through runoff.

Watershed Efforts

Collaboration between farmers, state governments, farm organizations, conservation groups, educational institutions, non-profit organizations, and community groups is vital to reducing nutrient pollution in the water and air. Farmers can play a leadership role in these efforts.

Use conservation drainage practices

Farmers can use conservation drainage practices to reduce air pollution. Conservation drainage describes practices including modifying drainage system design and operation, woodchip bioreactors, saturated buffers, and modifications to the drainage ditch system. Drainage water can carry soluble forms of nitrogen and phosphorus, so strategies are needed to reduce nutrient loads while maintaining adequate drainage for crop production.

One such practice is subsurface tile drainage, which is important for managing water movement on and through many soils, typically in the Midwest. Woodchip bioreactors are another practice that can be used to reduce air pollution. This practice involves placing wood chips in a containment area through which drainage water flows, reducing nutrient loads while maintaining adequate drainage for crop production.

Another practice is saturated buffers, which are areas of land that are allowed to become saturated with water to reduce the amount of drainage water that flows off the field. This practice helps to reduce the amount of nutrients that are lost from the field and improves water quality.

Finally, modifications to the drainage ditch system can be made to reduce air pollution. This includes practices such as installing pipes or ditches to carry drainage water away from the field, or using natural features such as wetlands or ponds to capture and treat drainage water. These practices can help to reduce the amount of nutrients that are lost from the field and improve water quality, which contributes to reduced air pollution.

Ensure year-round ground cover

Ensuring year-round ground cover is a crucial strategy for farmers to reduce air pollution. By planting cover crops or perennial species, farmers can prevent bare ground on their fields, which is essential for several reasons. Firstly, bare soil is susceptible to erosion, and this erosion can lead to the loss of valuable topsoil and the release of dust particles into the air, contributing to air pollution. Secondly, without ground cover, nutrients in the soil can be lost through leaching and runoff, leading to increased nutrient pollution in the air and nearby water bodies.

Farmers can adopt several practices to ensure year-round ground cover. One method is to plant cover crops, such as legumes, grasses, or mustard, between the rows of their main crops or during the off-season. These cover crops act as a living mulch, protecting the soil from erosion and suppressing the growth of weeds. Additionally, they can improve soil health by fixing nitrogen, increasing organic matter, and enhancing water infiltration.

Another approach is to utilise perennial species, such as deep-rooted grasses, which provide long-term ground cover. These perennials have extensive root systems that help to hold the soil in place, reducing erosion and preventing dust emissions. They also improve soil structure, water-holding capacity, and nutrient cycling, creating a more resilient and sustainable farming system.

Farmers can also implement conservation tillage practices to minimise soil disturbance. Conventional tillage methods, such as ploughing, leave the soil exposed and susceptible to erosion. By reducing the frequency and intensity of tilling, farmers can maintain ground cover, improve soil health, and decrease the likelihood of nutrients reaching waterways through runoff.

Furthermore, farmers can plant field buffers, such as trees, shrubs, and grasses, along the edges of their fields, especially near water bodies. These buffers act as a natural barrier, trapping or filtering out excess nutrients before they enter nearby water bodies or the atmosphere. This practice not only helps reduce air pollution but also protects water quality and provides habitat for beneficial insects and wildlife.

By implementing these strategies, farmers can ensure year-round ground cover, minimising soil erosion, nutrient loss, and air pollution. These practices contribute to a more sustainable and environmentally friendly farming system, improving air and water quality for the benefit of human health, ecosystems, and agricultural productivity.

Implement conservation tillage

Conservation tillage is a technique of soil cultivation that leaves a significant portion of the previous crop's residues on the soil surface after seeding. This helps to reduce and control the export of nutrients and sediment. Conservation tillage, or minimum tillage, is a broad term that includes no-till, strip till, ridge till, and mulch till systems. These techniques maintain plant residues on at least 30% of the soil surface after tillage activities.

Conservation tillage methods have been shown to improve soil health, reduce runoff, and limit erosion. They can also decrease carbon dioxide and greenhouse gas emissions, reduce reliance on farm machinery and equipment, and lower fuel and labour costs.

• No-till: The soil is left undisturbed by tillage during the entire year. Crop residues left on the soil surface may be disturbed in strips for planting or drilling seed.
• In-row subsoiling: The soil surface and residue are left undisturbed except for strips where the soil below the surface is loosened using deep-tillage implements.
• Strip-till: This practice retains the benefits of no-till but disturbs the row or zone using tillage practices only where the next crop will be planted. The space between the rows is covered with residue.
• Ridge-till: Specialized planters and cultivators are used to form and retain permanent ridges on which crops are grown. Crops are planted on top of the ridge after removing residue, which is left between ridges.

By adopting conservation tillage practices, farmers can contribute to reducing air pollution and promoting sustainable agricultural systems.

Control livestock access to waterways

Farmers can help reduce air pollution by controlling livestock access to waterways. Livestock operations are vulnerable to nutrient losses to the air, and when manure is left on farmland, it can be washed into waterways during rain or snow melt, or leach into the groundwater over time. This can cause eutrophication of water bodies, leading to hypoxia, fish kills, and a decrease in aquatic life.

Farmers can take several steps to control livestock access to waterways and reduce water pollution:

• Installing fencing along streams, rivers, and lakes: By erecting fences, farmers can block livestock from accessing water bodies, helping to restore stream banks and prevent excess nutrients from entering the water.
• Adopting nutrient management techniques: Farmers can apply nutrients (fertilizer and manure) in the proper amounts, at the right time of year, and with the correct methods and placement. This ensures that only the amount of nutrients that crops can utilize is applied, reducing the risk of runoff into water sources.
• Using conservation drainage practices: Implementing practices such as modifying drainage system design, utilizing woodchip bioreactors, saturated buffers, and changes to the drainage ditch system can help manage water movement and reduce nutrient loads while maintaining adequate drainage for crop production.
• Ensuring year-round ground cover: Planting cover crops or perennial species can prevent periods of bare ground on farm fields, reducing the risk of erosion and nutrient loss into waterways.
• Planting field buffers: Establishing trees, shrubs, and grasses along field edges, especially those bordering water bodies, can help absorb or filter out nutrients before they reach the water, acting as a natural barrier.
• Implementing conservation tillage: Reducing the frequency and intensity of tilling can improve soil health, decrease erosion, runoff, and soil compaction, and lower the likelihood of nutrients reaching waterways.

By following these practices, farmers can effectively control livestock access to waterways, reducing water pollution and minimizing the negative impact on aquatic ecosystems.

Frequently asked questions