Multidisciplinary research aims to improve water quality, prevent future crisis

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Harmful algal toxins—the culprit behind Toledo’s water crisis in August 2014—could be a thing of the past thanks to new technology being developed by Ohio State engineers.

Faculty from the College of Engineering are leading several different projects as part of the university’s Field to Faucet initiative, a water quality program launched to ensure safe drinking water while maintaining an economically productive agriculture sector.

The research projects will address ways to reduce excess nutrient runoff. One of the biggest contributors to harmful algal blooms (HABs) in lakes is excessive nitrogen and phosphorus from farms and cities upstream.

Measuring water safety in real time

When water safety is in question, public officials need fast answers. But current methods of testing for algal blooms are often anything but quick. The arduous process requires taking samples to a laboratory to be analyzed by special equipment, which often means a delay of several hours or even days before results are obtained.

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Thanks to research led by Electrical and Computer Engineering Professor Wu Lu, that delay could be reduced to as little as five minutes. Lu’s team is currently developing a new desktop device that will allow water treatment plant operators to accurately detect and measure harmful substances in real time. Targeting specific biological components that link directly with algal toxins, the sensor is able to identify substances of concern even at very modest levels.

The end result will allow plant operators to customize treatments based on type and quantity of waste detected. With the current system in place, plant operators must treat all toxins as worst-case scenarios, since the concentration isn’t known for several hours after samples are taken.

Farm management in the palm of your hand

Farmers soon will be able to manage the nitrogen and phosphorus in their fields with just the swipe of a finger.

A team of researchers led by John Fulton, professor of Food, Agricultural and Biological Engineering, is designing a suite of mobile device apps aimed at improving agriculture production and enhancing nutrient management at the farm level. The initial app will allow individual farmers and crop advisors to review recommendations regarding nitrogen, phosphorus and other nutrient application decisions based on Tri-State Fertilizer Recommendations. Farmers will get real-time information on the proper timing and application rate based on the crop and current growing conditions. New requirements in Ohio for those applying fertilizer to over 50 acres will make more accurate record keeping and documentation of best practices even more essential.

“Digital agriculture is quickly evolving as evidenced by internet-connected machines and handheld devices,” explained Fulton. “Ohio State is a leading institution around this digital agriculture evolution, and these mobile applications will help both the institution and the agriculture community continue to move forward in this space.”

Fulton said scientists have already seen farmers and their agronomists using the mobile applications to set up on-farm research, which in time will inform them of best practices to improve both their bottom line and nutrient stewardship. While the app will certainly improve life on the farm, the greater value is to the public.

“The overall benefit will be the science-driven solutions to water quality issues here in Ohio providing new insights into how nutrient practices can be tailored to reduce environmental concerns,” said Fulton.

The initial mobile app, called Ohio State PLOTS, is free and available for both Apple and Androiddevices.

Improving management of harmful algal blooms

Management of harmful algal blooms has traditionally focused on reducing the amount of phosphorus that reaches the watershed, but targeted efforts can be tough when the exact source of phosphorus is unclear.

Civil, Environmental and Geodetic Engineering Assistant Professor Paula Mouser and PhD candidate Michael Brooker are identifying unique signatures for the phosphorus found in the Lake Erie watershed, in hopes of learning its origins.

Research has historically focused on phosphate, an inorganic form of phosphorus commonly used in fertilizers, explained Mouser. Phosphates are the dominant form of phosphorus in natural waters and are easier to identify, making them the standard measurement for routine monitoring. However, organic phosphorus can come in literally hundreds of forms, from multiple sources, making it more difficult to trace and manage.

Mouser and Brooker collected samples from six different sources in the Sandusky River watershed: chicken, dairy and hog farm manure; runoff from farm fields with row crops, and wastewater treatment plant discharge, along with river water from farther downstream. Within each sample, they found between 100 and 300 different organic phosphorus compounds. The analysis will result in a unique signature for each of the samples, showing both similarities and major differences. Once researchers determine which phosphorus compounds come from each source, they can link those compounds to an upstream location.

“Theoretically if we can identify the source of the phosphorus, we can help improve management strategies to reduce phosphorus loading in our watersheds and reduce the outcomes that result from the algal blooms,” said Mouser.

Follow up sampling will occur in spring 2017 to expand the scope of the study.

Engineering a smarter fertilizer

Using manure to fertilize crops is a valuable, time-honored farming practice. But sometimes this useful resource can have negative impacts if it contains more nitrogen or phosphorus than a growing crop can absorb. The excess nutrients often end up in streams, rivers and lakes, and promote the growth of harmful algal toxins.

That’s why Food, Agricultural and Biological Engineering Professor Yebo Li and his team are developing a system that removes the nitrogen and phosphorus from animal waste. The multi-step process involves the removal of water from the manure and mixing the waste with lime or gypsum. The final product is both a solid cake fertilizer and concentrated nitrogen and phosphorus liquid fertilizer. Current tests are being conducted with digester material with manure trials expected to occur in the next several months.

Article by Meggie Biss, College of Engineering Communications