Meet the Water Productivity Researchers and Extension Educators, Drs. Steve Slack and Suat Irmak


On Monday, AgIsAmerica sat down with Drs. Slack and Irmak before their presentation on Capitol Hill. The presentation, More Crop Per Drop: Technology Implementation in Agriculture for Enhancing Crop Water Productivity, explored water productivity, quality, and quantity issues. Drs. Slack and Irmak were invited to speak to congressional staff as a part of a Lunch-N-Learn series. To listen to the presentation in full, please click here.

  1. Welcome to Washington! Tell us about yourselves.

Dr. Irmak: I’m a faculty member in the Biological Systems Engineering Department at UNL (University of Nebraska-Lincoln) under the Institute of Agriculture and Natural Resources. My research and Extension education programs focus on soil and water resources engineering, irrigation engineering, crop production. On my research team, I work with a large group of people, and we have numerous large scale projects every year. We work very hard to transfer all of the knowledge, data and information to help agricultural producers and other professionals make better, more informed decisions.

I’m Turkish-American. I received my undergraduate and MS degrees in Turkey and received my Ph.D. degree from the Agricultural and Biological Engineering Department at the University of Florida in 2002, and then moved to UNL as a faculty member.

IMG_2892 (1)Dr. Slack: I’ve spent 40 years in agricultural research, and for the last 16 years, I’ve been the Experiment Station Director and Director of Research at The Ohio State University. Prior to that, I did undergraduate and graduate work at The University of Arkansas and did my PhD at The University of California, Davis. I also spent time at The University of Wisconsin-Madison and Cornell University – all land-grant universities. My specialty, in terms of training, is plant pathology, or the study of plant diseases.

At Ohio State, my primary area of responsibility was research, but I worked very closely with the Extension Director. We jointly would fund faculty positions that had a combination of research and Extension responsibilities, and the importance of that from our perspective is that it allowed us to jointly focus on those issues that were important to the State of Ohio and surrounding states.

  1. What are the top water challenges we face here in the US?

Dr. Irmak: In Nebraska, and many other states, one of the biggest issues is water. Nebraska is blessed to have a great aquifer, but that isn’t the case in every part of the state. There are certain places where water is extremely limited. In certain districts, producers can only pump a certain amount of water, so as research and Extension professionals, we try to help them on implementing strategies as to how to best manage the resources. Water is always an issue.

Dr. Slack: Water is a major issue in Ohio, but it’s a different issue than what you’d find in Nebraska or the states west of the Mississippi. Our issues with water tend to be water quality issues – really looking at the nutrients in water and their impact as well as trying to devise plant management practices that affect water quality.

Dr. Irmak: On a larger scale, I think one of the biggest issues is how to best utilize resources as efficiently as possible while maintaining high yield with minimal input and optimal, or maximum, output. So, efficiency is always an issue. How do you optimize that? What kinds of technology and educational tools do you need? How do you implement them in production fields on large scales?

Dr. Slack: I agree, efficiency – whether you’re talking about quantity or quality of water – is an important issue, but I also think, superimposed on that, is all of the climate variables that we see. Currently, a lot of the water events that we have are pretty extreme, and trying to deal with them and that climate difference, which is accented by El Nino this year, really makes these issues of efficiency and management even more crucial.

  1. What are the top water challenges we face globally?

Dr. Irmak: In many cases, the challenges we face in the US are similar to the challenges we face globally, but there are some differences too. The challenges may be similar, but tools, educational opportunities, technology, and other resources available to deal with those issues can be very different. I’ve been to a lot of different places where this is the case. You know, land-grant university model, we may take it for granted, but it is an ingenious idea/model, and not many countries have a land-grant system. There have been discussions in different platforms about how we can transfer this model to other countries, like Brazil for example. The land-grant mission or model creates excellent opportunities and tools to deal with those global issues. And, agricultural engineering profession plays a vital role in this process.

Dr. Slack: One of the critical things that we face both nationally and internationally is the rapidly growing population and the need for food production, the need for water management, the need for efficiency in the use of energy. All of these things impact each other, and again, the clear advantage of our land-grant universities is that we have an opportunity on that mix of issues to work together with other colleagues for solutions. Resource management is not an issue of agriculture versus cities versus some other sector of society; this is really an issue that affects all of us.

As we look at the changes in climate, we’re going to face new water challenges, and we’re going to have to look at how we manage water both internally and amongst other countries. And doing that, while trying to feed a population growing worldwide, is going to be a challenge.

  1. How can technology enhance crop water productivity and management?

Dr. Irmak: There’s a significant interconnection between climate, water management, water quantity, water quality, and crop production. These are linked in a way that you cannot just separate one variable from the rest of the group. In water quality and quantity, for example, when introducing technology into production fields, you try to optimize or better manage irrigation applications. Technology can have many different forms from implementation to sensors, but technology can help us make better, more informed decisions. Technology can also minimize the human error associated with decision-making; we know exactly how much water to apply and when. Proper irrigation management can reduce the potential for nutrient and other chemical leaching to the surface and groundwater resources.

  1. What is irrigation, and what are its benefits and challenges?

Dr. Irmak: In the simplest terms, irrigation can be defined as supplementing water to crops in the absence of precipitation to meet crop water requirements to grow an optimal yield.

Dr. Slack: With the proper use of irrigation technology, you can put water where it’s needed and do that in an efficient manner.

Dr. Irmak: There are other several important benefits to irrigation; it provides stable productivity levels under changing climatic conditions. For example, one year, you may have good precipitation; the next year, you may not. Irrigation enables us to not only apply water in the right places at the right time with the right amount, but also enables us to do chemigation and fertigation, both of which distribute nutrients and other water soluble products throughout growing season rather than applying most or all of the nutrients in the beginning of the growing season, which enhances nutrient application ad uptake efficiency.

However, there are many challenges with irrigation. Improper irrigation management can result in nutrient leaching to other water sources. Over irrigation can reduce crop yields substantially due to an improper balance of nutrients, and the lack of water can also negatively impact crop yields.

Dr. Slack: I think it’s also important to realize that not only does technology change over time but crop management also changes over time. So, the issues you deal with – they might be nutrient issues – but how you manage them will change with the technology.

  1. How is land-grant research and Extension funded?

 Dr. Slack: This goes back to how our land-grant universities operate. We have a mix of funding that we would call capacity and competitive funding. The capacity funds put scientists on the ground in states and local arenas, so we can identify and prioritize those local and state issues. At the same time, we have competitive funding that allows us to identify and prioritize national issues. That mix from bottom-up, top-down allows us to really make sure that we’re addressing those issues that continue to impact our agriculture.

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