Mycoremediation of Phosphorus in Agricultural Runoff using Mycorrhizal-Plant Associations

View the project final report

Commodities

Practices

• Animal Production: inoculants, preventive practices
• Crop Production: agroforestry, nutrient cycling, nutrient management, pollinator habitat, water management
• Education and Training: demonstration, on-farm/ranch research, technical assistance, workshop, youth education
• Energy: energy conservation/efficiency
• Farm Business Management: new enterprise development, risk management, whole farm planning
• Natural Resources/Environment: afforestation, biodiversity, drift/runoff buffers, habitat enhancement, hedgerows, riparian buffers, riverbank protection, soil stabilization, wetlands
• Production Systems: agroecosystems, holistic management, organic agriculture, permaculture, transitioning to organic
• Soil Management: soil analysis, soil chemistry, soil microbiology, soil quality/health, toxic status mitigation
• Sustainable Communities: employment opportunities, infrastructure analysis, local and regional food systems, new business opportunities, partnerships, urban agriculture, urban/rural integration

This project proposes to demonstrate that phosphorus can be mitigated in drainage ways using mycofiltration. Forty-six years after the Clean Water Act’s passage, water quality remains an issue, as standards in water quality are exceeded. In Vermont, both farming and residential land uses are contributing to the phosphorus pollution. Monitoring at Shelburne farm, a sustainably run diversified farm on the eastern shore of Lake Champlain and the agricultural partner, shows elevated phosphorus in drainage ways. The likely source of the phosphorus is legacy phosphorus. Although mycofiltration has been successful in reducing pollutants, its potential has not been realized in on-farm installations. We are proposing to install a well-designed pilot swale at Shelburne Farm. The objective is to determine the efficacy of mycofiltration implemented as riparian mycorrhizae-inoculated plantings that intercept phosphorus before reaching neighboring drainage channel. The plantings will include native edible and pollinator plants. Mycorrhizae increase the efficiency of the plant root system to take up phosphorus by increasing the soil volume that the plant can explore for phosphorus. The project will measure dissolved and sediment-bound phosphorus before and after the plantings. Shelburne Farm is an excellent partner because part of their mission is outreach and demonstrating sustainable farming. Our corresponding outreach strategy involves engaging Vermont Youth Conservation youth in project implementation, the academic community via publishing and presenting our findings, the farming and local community through public talks, site visits, an active project website, and workshops.

This project seeks to discover whether mycoremediation strategies can decrease P load to the lake. Specifically this project will analyze whether mycorrhizal inoculated plantings decrease P concentrations in drainage water compared to drainage ways naturally colonized by non-native species.

Objective 1: Decrease the P concentrations in drainage water by greater 50%. We will measure the reduction of sediment-bound and dissolved phosphorus.

Objective 2: Measure the establishment of pollinator, edible, and medicinal plants.

Objective 3: Disseminate our results and information on green infrastructure to the regenerative agriculture and academic communities.

If these strategies succeed, farmers can replicate this model to decrease legacy P runoff without malaffecting the hydrology. Farmers will benefit from these low cost green infrastructure systems, which provide their farms with increased climate change resilience, diversified habitats, greater nutrient retention, and little long term maintenance as well as edible and medicinal products from the required biomass harvest.