Episode 44 - The Vadose Zone - A critical indicator for Nebraska groundwater quality

The vadose zone is the area between crop roots and the water table, and is a critically important region for storage, transport and transformation of chemicals that can impact groundwater quality. In this episode of the Water for Food Podcast, host Frances Hayes talks with Arindam Malakar, a researcher with the Nebraska Water Center (NWC, a part of DWFI) who studies Nebraska’s vadose zone and monitors the impacts of irrigation and fertilizer on groundwater.

Hayes is also joined by Marie Krausnick, assistant general manager for Nebraska’s Upper Big Blue Natural Resources District (NRD). The Upper Big Blue NRD and other NRDs across the state have partnered with the University of Nebraska-Lincoln and the Nebraska Water Center in researching nitrate concentration in their districts. While nitrate levels in some areas have decreased in the Upper Big Blue NRD, there has been an overall increase of 54% in the district.

In Nebraska, as in many parts of the world, one of the key chemicals monitored in the vadose zone is nitrate. Nitrogen is a critical plant nutrient, but once it sinks below the roots and enters the vadose zone, it becomes a liability: both an economic loss for the farmer and a potential public health risk for some rural communities where wells have not been recently tested. Excess nitrate in drinking water can cause adverse health effects, particularly in infants and vulnerable populations, as too much nitrate in the body makes it harder for red blood cells to carry oxygen. Contaminants, like nitrates, present in the vadose zone can eventually appear in the underlying aquifers. NWC takes soil cores all the way down to the groundwater table, sometimes over 100 feet, and tests them for nitrate and other contaminants. These cores are crucial for understanding how water and chemicals move through the soil and potentially reach groundwater. They can also be useful in predicting water quality issues. The Nebraska Water Center Water Sciences Lab has collected vadose cores for decades. To increase the usability of all this data, they launched the Nebraska Vadose Zone Program online portal in 2015 with funding from the Nebraska Environmental Trust, Nebraska Department of Environment and Energy (now the Nebraska Department of Water, Energy, and Environment), and several Natural Resources Districts (NRDs).

In the 43rd episode of the Water for Food Podcast, host Frances Hayes speaks with Claudia Ringler of the International Food Policy Research Institute (IFPRI) about the crucial link between irrigation and global health, expanding on Ringler's recent Heuermann Lecture as part of the 2025 Water for Food Global Conference and previous episodes in this podcast. Together they explore how irrigation can improve health outcomes while also addressing potential unintended negative impacts and how to avoid them when designing irrigation solutions. The conversation highlights successful irrigation projects, strategies for ensuring access to irrigation for beneficial outcomes like decreased malnutrition and improved hygiene, and necessary policy changes and international collaborations to maximize positive health impacts globally.

This special episode of the Water for Food Podcast commemorates the 15th anniversary of the Daugherty Water for Food Global Institute by sharing the story of its origin. Read the full historical account here.

The 15th anniversary year will be highlighted by a celebration reception at the upcoming 2025 Water for Food Global Conference, held in Lincoln, Nebraska, April 28-May 2. Learn more at waterforfood.nebraska.edu.

After years of dedicated work from many people and sectors, UNL has released new recommendations for nitrogen fertilization of irrigated corn. In this episode, Nebraska Water Extension Educator, Crystal Powers, talks to UNL professor of agronomy, Richard Ferguson, who has been involved in the project from the start.

In the 40th episode of the Water for Food Podcast, DWFI Director of Communications and Public Relations Frances Hayes sits down with Darren Siekman at the Valmont Industries headquarters in Omaha, Nebraska. Darren is the Vice President of Policy and Industry Strategy at Valley Agriculture, a Valmont Company. The two discuss Valmont's history and global presence and the importance of center pivot irrigation in agricultural productivity, as well as current challenges and future innovations in achieving global water and food security.

Navigating climate change: impacts on water stress and agricultural production in Nebraska

Nebraska, located in the U.S. “Corn Belt,” is well known for its agricultural and livestock production, generating around $31.1 billion in agricultural cash receipts in 2023. But how will climate change impact long-term agricultural production, and how can we adapt to changes to ensure water security and food supply for future generations?

In this episode, DWFI Communications Specialist Arianna Elnes talks to DWFI Research Assistant Professor Ivo Gonçalves, whose recent study explores the future of corn production in Nebraska. DWFI Senior Program Manager Renata Rimšaitė also joins to offer examples of sustainable water management strategies.

Key takeaways from Ivo’s study, How can Future Climate Change Affect the Corn Production System in Nebraska, USA?

• Climate change effects crop life cycle, growth and development
• To adapt, new varieties will need to be developed (but they will likely require more water)
• Efficient irrigation is essential to ensure consistent, high crop yields as temperatures and weather patterns change.
• There is a need for innovation in water management for sustained food and water security

Guests:

Ivo Zuition Gonçalves, Ph.D, Research Assistant Professor, Daugherty Water for Food Global Institute

Renata Rimšaitė, Ph.D, Senior Program Manager, Daugherty Water for Food Global Institute

Episode 38 - Irrigation expansion’s varying impacts on nutrition

Irrigation expansion can provide the water necessary to increase food production for our growing world. It can also be a means for moving farmers from simply producing enough food for their families to generating more income through domestic markets or export of additional production.

However, increasing use of irrigation can have varying impacts on the nutrition of the local communities and it’s important to consider these costs and benefits when striving to reduce poverty, end hunger and protect our water resources.

In this episode of the Water for Food Podcast, DWFI Director of Communications and Public Relations Frances Hayes talks with experts in irrigation and nutrition as they dive into the interconnectedness of irrigation, water availability and nutrition. Guests include Dr. Piyush Mehta and Assistant Professor Dr. Kyle Davis, both in the Department of Geography & Spatial Sciences at the University of Delaware.

View the research mentioned in the episode here.

ILIMS Deputy Director Jude Cobbing - Opportunities of Irrigation and Mechanization

In November 2023, the Daugherty Water for Food Global Institute announced a new USAID Feed the Future Innovation Lab for Irrigation and Mechanization Systems (ILIMS). ILIMS enhances global food security by generating research-based solutions to support the growth of vibrant irrigation and mechanization markets; develops strong institutions and local capacity for their sustainability; and fosters opportunities for equitable access for smallholder farmers.

In this episode, DWFI Communications Specialist Arianna Elnes speaks with the new ILIMS Deputy Director Jude Cobbing about his background and interest in ILIMS, the opportunities he sees with irrigation and mechanization, and upcoming projects for ILIMS. For more information, and to respond to RFA’s, visit: waterforfood.nebraska.edu/irrigandmech