Riparian buffer nutrient dynamics and water quality

Authors: Young, Eric; ROSS, DONALD - University Of Vermont; Jaynes, Dan

Submitted to: Frontiers in Environmental Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/14/2019
Publication Date: 5/29/2019
Citation: Young, E.O., Ross, D.S., Jaynes, D.B. 2019. Riparian buffer nutrient dynamics and water quality. Frontiers in Environmental Science. 7:76. https://doi.org/10.3389/fenvs.2019.00076.
DOI: https://doi.org/10.3389/fenvs.2019.00076

Interpretive Summary: Maintaining surface and groundwater quality in many agricultural regions around the world continues to be challenging. One of the most frequently recommended best management practices to reduce nonpoint source pollution transport risk to streams in agroecosystems are riparian buffers. While buffers can be effective at removing sediment and particulate-bound nutrients in surface runoff, their efficacy varies widely, especially with respect to dissolved, inorganic forms of nitrogen and phosphorus. Water flow pathways entering and exiting buffers (i.e., hydrology) often set the stage for potential water quality functions of buffers. Interactions between hydrology, soils, vegetation communities, and land management (or lack thereof) can profoundly affect nutrient flows and buffer performance. Many unanswered questions remain with respect to water quality functions of buffers and the combination of factors controlling nutrient pollutant mitigation in different settings. The goal of our research topic was to feature studies addressing aspects of riparian buffer management with the goal of optimizing their water quality and ecological functions (ecosystem services).

Technical Abstract: Mitigating nonpoint source pollution from agroecosystems remains a global challenge. Given the close linkage of nitrogen (N) and phosphorus (P) cycling to both agricultural and aquatic productivity (eutrophication), careful nutrient management and wise use of best management practices (BMPs) are essential to reduce nutrient runoff risk to streams. Riparian buffers (permanent, uncultivated areas between cropland and streams) can reduce sediment and nutrient fluxes in surface runoff from uplands, however, attenuation capacity varies widely depending on several site-specific factors that can be difficult to predict. In some cases, buffers have little impact on runoff water quality and may serve as a source of nutrients to streams. From a riparian water quality management perspective, coupling hydrologic pathways with landscape attributes regulating N and P source availability (i.e., C/N, labile P status, redox potential, pH) is an important approach for water quality models aimed at identifying watershed critical source areas and prioritizing BMPs for P mitigation. In this light, our research topic includes two studies on riparian P fate and transport, a study evaluating riparian plant harvesting impacts on community diversity/abundance/potential nutrient removal, and a hypothesis/theory article addressing riparian corridor N dynamics within and among major biomes.