Challenges and successes in identifying the transfer and transformation of phosphorus from soils to open waters and sediments

Authors: ROSS, D. - University Of Vermont; Young, Eric; JAISI, D. - University Of Delaware

Submitted to: Soil Systems
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/2021
Publication Date: 10/19/2021
Citation: Ross, D.S., Young, E.O., Jaisi, D.P. 2021. Challenges and successes in identifying the transfer and transformation of phosphorus from soils to open waters and sediments. Soil Systems. 5(4):65. https://doi.org/10.3390/soilsystems5040065.
DOI: https://doi.org/10.3390/soilsystems5040065

Interpretive Summary: Phosphorus (P) is a critical element for terrestrial and aquatic plant productivity. As such, P is an important nutrient for crop growth, however P that is transported by surface and subsurface runoff water to streams can contribute to eutrophication and water quality decline. Unlike nitrogen, which is more water-soluble and subject to atmospheric losses, P tends to accumulate in soils, often termed “legacy” P. Once considered relatively immobile in the soil environment, research over the past several decades has clearly shown that P is vulnerable to losses in a range of forms including soluble inorganic/organic P, particulate P, in addition to a range of nano-particulate and colloidal species. A range of agricultural best management practices can help reduce P loss from cropland, with erosion control remaining an important consideration for mitigating particulate-bound P. However, soluble P losses in runoff can pose a substantial water quality risk, especially where legacy P concentrations are high. In-field practices including cover crops, manure injection/incorporation, and precision fertility management can help reduce P loss potential. Edge-of-field management practices such as riparian buffers along streams are also important for mitigating P transport potential to streams, however buffer efficacy is strongly linked to site-specific characteristics including, buffer width, plant species/distribution, soil type, hydrology, soil P forms/amounts, and other factors. This special journal issue focuses on various aspects of P fate, transport, and management with emphasis on processes and practices to mitigate P losses to water.

Technical Abstract: Phosphorus (P) is an essential crop nutrient needed for optimal crop production, however, excess P loss to waterways from anthropogenic activities including agriculture contribute to water quality degradation. Once considered relatively immobile in soil environments, research over the past several decades has clearly shown that P can be readily mobilized and transported in both surface (overland flow) and subsurface water flows in dissolved and particulate forms. Various in field nutrient management practices and riparian buffers (permanently vegetated areas along streams) critically affect P fate and transport but vary in their ability to decrease P loss from cropland to water resources. In this special issue, we invited research and review articles addressing the transfer and transformation of P across the landscape using novel research methods, a review of successes and failures with underlying causes, or data-driven approaches with the goal of improving water quality. This issue contains eight original research articles and two review papers covering a range of field and laboratory-based P fate and transport aspects, including mineral-P interactions, P speciation with x-ray near-edge structure spectroscopy, streambank contributions of legacy P, in addition to impacts of climate change, weathering, vegetation, and manure management effects on P loss potential and water quality. Collectively, these articles elucidate our understanding of P behavior in the environment and link soil-microscale processes to field and larger watershed scales.