Reducing Farm Pollution: Strategies For Sustainable Agriculture

Agriculture has been a crucial means of human survival for thousands of years, but modern agricultural practices have led to a process of agricultural pollution, causing the degradation of the ecosystem, land, and environment. To reduce pollution in farms, farmers can adopt several strategies, including implementing nutrient management techniques, using conservation buffers, ensuring year-round ground cover, and engaging in watershed efforts. These methods can help prevent nutrient runoff, stabilize stream banks, and improve water quality, benefiting both the environment and human health.

Implement nutrient management techniques

Implementing nutrient management techniques is a crucial step in reducing pollution in farms. Nutrient management practices can be improved by applying the right amount of nutrients (fertilizer and manure) at the right time of year, using the correct method, and placing them in the right spot. This accuracy can prevent runoff from farm fields, which could otherwise affect other farms, livestock, or water supplies.

Farmers can benefit from adopting SMART Nutrient Management, which includes the 4Rs of nutrient stewardship: the right Source, right Method, right Rate, and right Timing. This approach emphasizes smart activities to reduce nutrient loss by assessing comprehensive, site-specific conditions.

• Source: Choose the right nutrient sources that best match the needs of your crop and soil while minimizing the risk of nutrient loss specific to your site. This choice depends on factors such as local soil and climate conditions, the specific crop, and conservation practices like reduced tillage, no-till, or cover crops.
• Method: The method of application can significantly impact nutrient management. Nutrient injection, for example, delivers nutrients directly to the root zone of the crop, increasing their accessibility. Incorporation may also be necessary for certain sites to ensure plants can adequately access the nutrients and reduce the risk of nutrient loss in runoff events.
• Rate: Determining the application rate requires considering factors such as testing, soil health practices, and technology. Soil and plant testing can identify the specific nutrient needs, while soil health practices like no-till or cover crops can naturally increase soil organic matter, potentially reducing fertilizer needs. Variable rate application technology can further improve nutrient efficiency by delivering specific amounts based on historic yields and soil-test nutrient levels.
• Timing: Appropriately timing the application of nutrients is critical for maximizing uptake and effectiveness. This timing should consider crop demand, weather and seasonal conditions, and the technology available for application.

By adopting SMART Nutrient Management and considering the unique characteristics of their farms, farmers can reduce input costs, maximize yields, and efficiently manage nutrients to support their bottom line and protect the environment.

Create conservation buffers

Conservation buffers are an effective and cost-efficient best management practice that can be used to improve water quality. They are strips of land in permanent vegetation designed to intercept sediment and nutrients, reduce soil erosion, and protect the soil. They also manage environmental attributes such as air and water quality and fish and wildlife habitats, thereby increasing biodiversity and beautifying agricultural landscapes.

Conservation buffers can be used in several ways to reduce pollution in farms:

Placement of Conservation Buffers

Conservation buffers can be placed in different locations to reduce pollution in farms. For example, a grassy strip between a field and a wetland can act as a conservation buffer, absorbing excess nutrients from fertilised fields before they reach the wetland. Similarly, a hillside farm pasture that gently slopes towards a stream can be fenced off, creating a buffer zone that prevents livestock from accessing the stream bank and allows space for nutrients from manure to be absorbed before reaching the water.

Types of Conservation Buffers

There are several types of conservation buffer strips that can be implemented, each serving a specific purpose:

• Contour grass strips or wind trap strips: These strips consist of rows of different perennial vegetation that reduce wind damage to young plants, conserve soil moisture, and minimise soil erosion.
• Filter strips, grassed waterways, riparian buffer zones, wellhead protection areas, and wetlands: These buffers are used for water control and quality improvement, preventing further degradation of soil and water quality.
• Field borders: Vegetation in field borders can be planted to accommodate travelling machinery and turning areas.

Benefits of Conservation Buffers

Conservation buffers offer multiple benefits for farms:

• Reduced soil erosion: Conservation buffers help to minimise soil erosion by reducing surface runoff and moderating water temperatures.
• Improved water quality: Buffers can trap and degrade a portion of the runoff absorbed in sediments or dissolved in water, including nutrients such as nitrogen and phosphorus, and reduce the amount of pesticides and pathogens in the water.
• Flood prevention: By reducing water runoff from fields, conservation buffers can help mitigate downstream flooding.
• Increased profitability: Implementing conservation buffers can take marginal land out of production, increasing profitability.
• Enhanced wildlife habitat: Conservation buffers can improve wildlife habitats and increase biodiversity by providing vegetation and shelter for various species.
• Improved air quality: Conservation buffers can reduce chemical emissions, improving air quality.
• Odour reduction: Buffers can help minimise odours associated with farming activities.

Control livestock access to waterways

Livestock access to waterways can have a detrimental impact on water quality, causing increases in the levels of suspended sediment, nutrients, and pathogens. Fencing is a convenient method of controlling livestock access to waterways. Here are some ways to control livestock access to waterways:

• Install fencing: Putting up fences along streams, rivers, or lakes can help restore stream banks and prevent livestock from dragging nutrients or other agricultural pollutants into the water. It is important to ensure that the fencing adequately restrains the livestock and is designed based on factors such as slope, animal species, and animal and vegetation density.
• Provide alternative water sources: Giving livestock an alternative water source can help maintain a healthy and diverse aquatic ecosystem. This approach also ensures that sediment, bacteria, and nutrients are not deposited into the water when livestock drink or cool off in it.
• Implement buffer strips: Buffer strips are sections of land with dense vegetation, including trees and shrubs, that help protect water quality by reducing the runoff of pollutants, such as nutrients, bacteria, sediment, and other contaminants into surface water.
• Create filter strips: Filter strips are similar to buffer strips but focus on reducing manure runoff and soil erosion by using specific types of maintained vegetation.
• Limit livestock entrance to water: If alternative water sources are not feasible, limiting the location where livestock can access the water can help reduce the negative impact on the watercourse. Provide firm footing to prevent bank erosion and fence off the area to restrict livestock access to the edge of the waterway.
• Construct limited access ramps: These structures allow cattle partial access to the water, reducing harm to the habitat while preserving their drinking source.

Improve soil management

Improving soil management is key to reducing pollution in farms. Here are some ways to do that:

Conservation Buffers

Planting trees, shrubs, and grasses along the edges of fields can act as conservation buffers, helping to absorb or filter out excess nutrients before they reach water bodies. This is especially beneficial for fields bordering water sources.

Nutrient Management Techniques

Farmers can improve nutrient management practices by applying the right amount of fertilizer and manure, at the right time of year, using the correct method, and placing it in the right location. Accuracy in nutrient management can help prevent runoff and reduce pollution.

Conservation Tillage

Reducing the frequency and intensity of tilling fields can improve soil health, reduce erosion, and decrease the chances of nutrients reaching waterways through runoff. Conservation tillage also helps reduce soil compaction and improves crop establishment time and energy use.

Cover Crops and Year-Round Ground Cover

Planting cover crops or perennial species can prevent bare ground on farm fields, especially during periods when the soil is most susceptible to erosion and nutrient loss into waterways.

Manure Management

Having a proper manure management plan is crucial. Using manure can help replace fertilizer applications and increase soil productivity over time. This includes soil sampling, assessment, and investing in manure storage structures to avoid spills and water contamination.

Crop Rotation

Crop rotation is an essential aspect of organic farming. By rotating crops with different characteristics and requirements, farmers can more effectively utilize resources and improve soil health. It also helps in weed and pest management, as well as reducing the risk of diseases.

Green Manure

Green manure, or the practice of working a legume crop into the soil, provides nutrients for the organisms and subsequent crops. It helps fix nitrogen into the soil and improve phosphorus availability, contributing to overall soil fertility.

Soil Testing and Amendments

Soil testing can provide valuable information about soil nutrients, pH levels, and organic matter content. Based on the results, farmers can make informed decisions about fertilizer usage and adopt appropriate soil management strategies.

Animal Manure

Animal manure provides nutrients to plants and improves soil structure, water infiltration, and resistance to erosion. Proper application and incorporation of manure are crucial to prevent environmental contamination and ensure optimal plant growth.

By implementing these practices, farmers can significantly improve soil management, reduce pollution, and promote sustainable agriculture.

Reduce ammonia emissions

Ammonia is a volatile nitrogen compound that is released when slurries, manures and nitrogen fertilisers come into contact with air. When mixed with other air pollutants, ammonia can form toxic particles, leading to poor air quality and health problems.

Cover Slurry and Digestate Stores

Covering slurry pits and silos with a roof, floating cover, floating bodies (plastic, straw or bark) or a naturally forming floating cover can reduce ammonia emissions. Open lagoons and slurry stores allow ammonia to escape into the atmosphere, so covering these stores will create a concentration of ammonia beneath the cover, suppressing further ammonia production.

Use Low-Emission Techniques for Spreading Slurry and Digestate

Techniques such as injection, trailing shoe or trailing hose can reduce ammonia emissions by minimising the exposed surface area of slurry or other liquid manure. Up to 80% of the nitrogen contained in slurry can be lost to the environment when splash plate equipment is used, whereas shallow injection can reduce ammonia emissions at spreading by up to 70%.

Incorporate Manures into Bare Soils Within 12 Hours of Spreading

Incorporating manures into bare soils within 12 hours of spreading can help to avoid ammonia losses.

Wash Down Animal Collection Points Soon After Use

Keeping floors in livestock areas clean will reduce ammonia emissions. Collecting yards, livestock handling areas and parlours should be scraped and washed down as soon as possible after use.

Efficient Use of Protein in Livestock Diets

Ammonia emissions are linked to the surplus nitrogen excreted by animals as urinary urea, which is derived from dietary protein. By ensuring that the levels of protein in livestock diets are well-matched to their nutritional needs, less nitrogen will be excreted, and less ammonia will be produced from the slurry.

Frequently asked questions