PATH4MED – Demonstrating innovative pathways addressing water and soil pollution in the Mediterranean Agro-Hydro-System

Reducing nitrate pollution requires knowing where it comes from. However, fertilisers, livestock manure and wastewater can all increase nitrate concentrations in water, making it difficult to identify the most appropriate mitigation measures using conventional monitoring alone.

PATH4MED demonstrates how nitrate isotope analysis can complement routine water quality monitoring by distinguishing between different nitrate sources and improving understanding of nitrogen processes within agricultural catchments. Combining isotope analysis with hydrochemical monitoring provides more reliable information for identifying pollution pathways and targeting mitigation measures where they are most effective.

For water managers and environmental authorities, better source identification supports more effective river basin management and helps evaluate whether nutrient reduction measures are achieving the desired results. The approach is particularly valuable in catchments where multiple pollution sources coexist and evidence-based management is needed to improve water quality.

• PATH4MED website

Water quality and diffuse agricultural pollution change over time as a result of weather conditions, farming practices and seasonal variations. Short-term monitoring often provides only a partial picture, making it difficult to evaluate whether management measures are achieving the expected environmental improvements.

PATH4MED demonstrates how long-term environmental monitoring combined with process-based modelling improves understanding of pollution pathways at catchment scale. Continuous monitoring of streamflow, groundwater, water quality and meteorological conditions provides reliable data for testing different management scenarios before they are implemented.

Farmers, water managers and public authorities can use this information to make more informed decisions, evaluate the likely impact of alternative management practices and prioritise investments where they will provide the greatest environmental benefit. Long-term datasets also strengthen confidence in policy measures and support adaptive water management under changing climatic conditions.

• PATH4MED website

Livestock manure is a valuable source of nutrients, but poor storage or inappropriate application can lead to nitrogen and phosphorus losses, increasing the risk of water pollution and reducing nutrient-use efficiency.

PATH4MED promotes practical nutrient management by helping farmers better document manure production, storage and application while matching nutrient inputs to crop requirements and local environmental conditions. The project demonstrates how improved planning and record-keeping support more efficient nutrient use and reduce environmental risks.

By considering weather conditions, crop demand and field characteristics before manure application, farmers can reduce nutrient losses, improve fertiliser efficiency and lower unnecessary input costs. Better manure management also supports compliance with environmental regulations and contributes to more sustainable livestock production.

Regular planning, record-keeping and appropriate manure application help farmers protect water resources, improve nutrient efficiency and support the long-term sustainability of livestock production.

• PATH4MED website

Increasing pressure on water resources means that irrigation must become more efficient without compromising crop productivity. Applying too much or too little water can reduce yields, increase production costs and contribute to nutrient losses that affect surrounding water bodies.

PATH4MED demonstrates how soil moisture sensors, weather information and Decision Support Systems (DSS) can help farmers optimise irrigation according to crop needs and local environmental conditions. By combining real-time field data with digital tools, irrigation schedules can be adjusted to apply the right amount of water at the right time.

The approach helps farmers improve water-use efficiency, reduce unnecessary irrigation, lower energy consumption and minimise nutrient losses. It also supports more informed farm management decisions while maintaining crop productivity. Successful implementation depends on proper sensor installation, regular maintenance and training in the interpretation of irrigation recommendations.

• PATH4MED website

Managing irrigation efficiently across large agricultural areas requires timely information on crop conditions, soil moisture and water availability. Field surveys alone are often expensive, time-consuming and unable to detect localised problems early enough to support effective management decisions.

PATH4MED demonstrates how satellite imagery, drone observations and field measurements can be combined to monitor crop development, irrigation performance, soil moisture and environmental conditions throughout the growing season. These digital tools provide regular and reliable information that helps identify irrigation problems, erosion risks and areas where water resources are under pressure. By integrating Earth Observation with field monitoring, the project supports more informed and timely management decisions.

Farmers, irrigation organisations and water authorities can use these technologies to optimise irrigation scheduling, identify priority areas for intervention and monitor agricultural conditions more efficiently. The use of freely available satellite data also helps reduce monitoring costs while improving resource efficiency, supporting sustainable agricultural production and better protection of water resources.

• PATH4MED website

Protecting rivers, lakes and irrigation water from agricultural pollution requires reliable and timely information on water quality. Conventional biological monitoring is often time-consuming, depends on specialised taxonomic expertise and may not detect early ecological changes before pollution becomes more severe.

PATH4MED demonstrates how environmental DNA (eDNA) and environmental RNA (eRNA) can complement existing monitoring methods by providing faster and more comprehensive information on aquatic ecosystems. By analysing genetic material naturally released by organisms into the water, these methods can detect changes in biodiversity that indicate nutrient pollution and ecological deterioration at an early stage. The approach has been tested under different environmental conditions and shows strong potential to support existing Water Framework Directive monitoring programmes.

For farmers, irrigation managers and environmental authorities, earlier detection of water quality changes means that corrective measures can be taken before pollution becomes more difficult and costly to manage. Better information supports more efficient nutrient management, helps protect water resources and contributes to more sustainable agricultural production. As molecular monitoring methods become increasingly standardised, they can provide a practical and cost-effective addition to routine water quality assessment.

• PATH4MED website

Nutrients, sediments and pesticides transported by agricultural runoff can significantly reduce water quality and affect aquatic ecosystems. Many conventional mitigation measures require substantial investment and may provide limited environmental benefits beyond pollution control.

PATH4MED demonstrates how nature-based solutions, such as treatment wetlands and riparian buffer strips, can reduce diffuse agricultural pollution by intercepting runoff before it reaches rivers and streams. These natural systems filter nutrients and sediments while supporting biodiversity, improving ecosystem resilience and contributing to healthier agricultural landscapes. The project shows that combining landscape planning with natural processes provides an effective and sustainable approach to protecting water resources.

Farmers and land managers can integrate treatment wetlands and vegetated buffer strips into existing agricultural systems with relatively low maintenance requirements. Besides improving water quality, these measures can reduce nutrient losses, enhance biodiversity, support natural flood regulation and contribute to compliance with environmental legislation. Selecting suitable locations and native plant species is essential to maximise their long-term performance and environmental benefits.

• PATH4MED website