Tracking Phosphorus: A Watershed-Scale Study on Preventing Eutrophication in Kansas Streams

Insight: In a world where the nutrients that feed our crops can also choke our rivers, managing phosphorus has become a defining challenge for sustainable agriculture. Working directly with soils, sediments, and runoff in Kansas watersheds taught me that what we often label as “waste” can also be part of a regenerative solution—if approached with scientific rigor and a circular mindset. I envision a future where nutrient stewardship is no longer a reactive measure, but a proactive strategy embedded in environmentally sound innovation.

During my graduate studies at Kansas State University, I led a research project that deeply shaped my professional identity: a watershed-scale investigation into phosphorus transport, aimed at mitigating eutrophication in agricultural landscapes. This work positioned me at the intersection of environmental chemistry, water resource management, and applied sustainability—and marked a turning point in how I saw my role as an engineer and problem solver.

As a research assistant in Dr. Nelson’s Soil Fertility Lab, I was fully involved in each phase of the project—from framing the research questions and leading field campaigns to designing lab tests and interpreting results. Our goal was to understand how phosphorus moves through agricultural watersheds, especially during storm events, and to identify best practices that could curb nutrient runoff without compromising crop productivity.

Phase 1: Framing the Problem and Reviewing the Literature

We began by examining the scientific literature to build a robust methodological foundation. I explored the behavior of phosphorus in soils and sediments, the geomorphology of stream channels, and how agricultural practices influence nutrient mobility. This phase was essential in refining our approach and ensuring our field design was grounded in evidence.

Phase 2: Field Sampling and Watershed Characterization

Our fieldwork took us across two major watersheds in Kansas. I led the sampling campaigns, collecting water, soil, and sediment samples across diverse landscape profiles. We measured variables such as streambank erosion, slope gradients, and soil properties to better understand the physical and chemical conditions that drive phosphorus transport.

Phase 3: Laboratory Analysis

In the lab, I conducted detailed analyses to quantify phosphorus concentrations using equilibrium phosphorus concentration (EPC₀) and phosphorus adsorption capacity (PAC) tests. Each data point gave us insight into the system's capacity to buffer or release phosphorus, revealing the nuanced ways land use and hydrology intersect.

Phase 4: Data Interpretation and Knowledge Sharing

With the support of SAS software, I performed statistical analyses to detect patterns in phosphorus retention and mobilization. The results showed that stream sediments were generally not a major source of phosphorus under baseflow conditions—but during storm flows, bank erosion became a significant contributor. This finding led us to recommend practical conservation measures such as no-till farming, contour plowing, and streambank stabilization.

Environmental and Technical Relevance

Our research provided Kansas farmers and water managers with actionable data to better manage phosphorus while supporting agricultural resilience. The study was later published in the Journal of Environmental Quality and presented at national conferences, contributing to the broader dialogue on nutrient management in the Midwest.

This project was more than a scientific exercise—it was a formative experience that deepened my commitment to sustainability through innovation. It reminded me that impactful environmental solutions begin with asking the right questions, working across disciplines, and never losing sight of the systems we’re trying to protect. I carry those lessons with me in every project I lead today.

For those interested in the detailed scientific findings that supported this project, I invite you to explore my peer-reviewed publication:

“Phosphorus Adsorption and Desorption Potential of Stream Sediments and Field Soils in Agricultural Watersheds”, Journal of Environmental Quality, 2011, Vol. 40:144–152.

You can also consult my master’s thesis, “Sources of Phosphorus Loading in Kansas Streams”, which offers a comprehensive analysis of nutrient dynamics across agricultural watersheds.