20 July 2024

Challenges and Indicators for Resilient and Sustainable Farming systems

Karen Daly and David Wall discuss the challenges and strategies for achieving environmental sustainability in agriculture, focusing on reducing emissions, improving water quality, enhancing biodiversity, and adopting new technologies.

Farmers have faced and overcome the challenge of economic, social and environmental sustainability for some time now, however, challenges concerning agriculture’s role in maintaining and improving the surrounding environment have been increasing in recent years. The EU Green deal has set targets to halt biodiversity decline, improve water quality, reduce fertiliser and pesticide use and protect soil health. In Ireland, the agricultural sector is facing multiple policies and frameworks and very challenging environmental targets. The sectoral targets to reduce greenhouse gas and ammonia emissions, improve water quality and reverse the decline in farmland biodiversity are fast approaching. The trends in emissions, water quality and biodiversity continue to decrease or remain static and we urgently need to work together to implement solutions and technologies that are known to reverse these trends. Farmers need technologies that allow them to combine economic and environmental sustainability.

Livestock production systems

Technologies at the systems level are required to reduce emissions per hectare to meet the 25% target by 2030 and climate neutrality by 2050. Continued improvements in grazing management, breeding of efficient animals, reducing the age of slaughter and increasing home-grown feed supplementation will lead to further reductions in emissions. In addition to these proven technologies for improving livestock production systems, newly emerging technologies are being tested for Irish systems such as feed additives for reducing biogenic methane and breeding of lower methane emitting animals in future, hold the potential to reduce emission further over time.

Greenhouse gas emissions

The 25% greenhouse gas reduction target will be extremely challenging and the recent emissions increases will have to be reversed. Nitrous oxide (N₂O) from nitrogen fertiliser, manures and urine accounts for approximately 30% of agricultural emissions. The remaining 70% comes from slurry management and directly from the animals. Agricultural soils are a source of emission in the Land use and forestry part of the inventory. Carbon sequestered in our mineral soils is four times lower than the carbon lost from agricultural peat soils.

Reduce nitrogen fertiliser use

One big challenge is to dramatically reduce reliance on imported, fossil fuel derived fertilisers. There are a range of proven technologies today to reduce this reliance. Optimising soil fertility releases c.70kg N/ha from the soil and reduces fertiliser requirements. Soil fertility is important for clover/ multispecies sward establishment and enabling a significant reduction in nitrogen fertiliser use. Use of using low emission slurry spreading increases the nitrogen supply in slurry, reducing fertiliser requirements. Where chemical N is used then replacing CAN and urea with protected urea can reduce emissions by over 70%. New research is showing lower emissions when certain low nitrate compound fertiliser are used and that optimal soil fertility can directly reduce emissions by approximately 40%.

Carbon farming and sequestration

A carbon farming framework for Ireland is under development by government that needs accurate information to monitor, verify and report on carbon capture and removals and research is underway to bring this data to government. Strategies that we can adopt now to increase carbon sequestration include increasing trees on farms through hedgerow management, on farm forestry and agro-forestry. Currently our national inventories are using default values to account for carbon emissions and sequestration in agricultural soils and research is underway to refine these emission factors for different soil types, land-use, land management practices. Research on the effects of water table management of drained grassland peat soils and improving the accuracy of mapping our drained grassland peats is getting underway. This will improve the accuracy of the inventory and identify technologies to reduce emissions from soils and the management practices to enhance carbon sequestration.

Water quality

The effect of agriculture on water quality has been subject to large amounts of research over the past 20 years. While Irish water quality is above average within the EU, only 54% of Irish surface waters are at satisfactory or good status, with the presence of too much P and N in our waters as the primary challenges. Agriculture has a significant role to play in helping achieve good water quality targets and the Teagasc Better Farming for Water campaign has a clear objective to reduce nutrient and sediment loss to water through its 8-Actions for change focussing on nutrient management, farmyard management and land management. Good nutrient management planning is a major corner stone to reducing diffuse nutrient losses. The Agricultural Catchments Programme have greatly improved the science behind water quality and have developed a new critical source area tool for highlighting areas for farmers to address on their farms. The Agricultural Sustainability Support and Advisory Programme (ASSAP) provides free advice to farmers on appropriate practices to improve water quality.

Biodiversity

The EU biodiversity strategy aims to have at least 10% of agriculture area under high-diversity landscape features by 2027. The area of seminatural habitat and number of bird species and pollinators has declined. A recent survey of intensively managed farms found that the median wildlife habitat area was 5% (tillage), 6% (intensive beef) and 6.6% (intensive dairying). There are many ways that farmers can actively improve habitats and wildlife on their farms achieve the 10% target. A range of technologies from multispecies swards, hedgerow management, field margins and results based payments for biodiversity. Research is also investigating approaches to quantifying farmland habitats and management plans.

Summary

There are a large number of strategies and solutions available to improve environmental sustainability on farms. The researchers and advisers are available to support farmers on how to adopt these on their farms. There are insights to future research investigating emerging technologies to help farmers further improve sustainability and resilience of their farming systems. Many of these actions and strategies have multiple co-benefits and also improve farm profitability.