Dr. Uttam K. Saha, Ph.D. – Georgia Extension Lab

At the UGA extension, Dr. Uttam K. Saha, Ph.D., has been doing agricultural analysis for the state residents of Georgia for 9 years, offering valuable information to farms, families, the environment, and 4-H youth development. Recently, Dr. Saha published a paper, “A Comparison of Diffusion-Conductimetric and Distillation-Titration Methods in Analyzing Ammonium- and Nitrate-Nitrogen in the KCl-Extracts of Georgia Soils”, involving the use of  Timberline Diffusion/Conductivity method compared to Distillation -Titration for the determination of ammonia in soil samples. After the publication, we interviewed Dr. Saha to find out more about his work at UGA extension and his thoughts on the TL-2800 Ammonia Analyzer.


Timberline: You have an interesting background Dr. Saha. Can you tell us about it?

Uttam: I’m a soil chemist by training and then I did a lot of different things that I do in my work. I educated myself on various things and I’ve been practicing those. I have contributions not only in soil chemistry but in various environmental and crop production related issues. I got my initial education in Bangladesh where I was born and then I moved to Japan to get my Ph.D. Later on, I had a postdoctoral training phase for a couple appointments in Japan and in Canada as well. Then I had a job at the University of Florida for three and a half years with the soil chemistry and environmental remediation group there. Finally, I accepted my current faculty position at the University of Georgia where I have been working since 2009.

Current Position

Timberline: What does a typical day for you look like?

Uttam: This is an extension lab. I have the responsibility of doing analytical work for the citizens of Georgia. We have local University of Georgia extension offices in each county. There are 159 counties in Georgia. It’s huge. We provide services primarily through our extension offices so that they can work with their local clientele as long as the problem of the citizen in the local setting falls in my subject area which is feed & forage quality, drinking water quality, wastewater quality, emerging contaminants, soil, plant, etc.

J: What is the most rewarding aspect of your job?

U: The most important thing is I am in a situation where I have the opportunity to know the problem of the society, but at the same time people have the opportunity to know from me some emerging issues in my field that merit attention of the society. What people try to accomplish. For example someone wants to go for a bakery business. I try to help them to determine the nutritional quality of their raw materials. Someone has a drinking water well in their home and my job is to advise them on how to determine the safety of drinking water so that they can have safe drinking water and so they can be free from the harmful effect of many drinking water contaminants. So every day I listen to many unique situations from people who need my help. I can use my skills and give them advice. There is a continuous training need for our extension office people. They are called extension agents, program assistants, and other types of professionals. I have an ongoing responsibility to train them in my field so they can solve the problem their clientele, who are ordinary citizens most of the time –  small business/big businesses as long as their situations fall under my subject area.

It is a very good area. My own education makes sense to me now. I think my education is more meaningful than before because I’m helping people. Using my skills to improve the quality of the environment. That’s very fulfilling to me in the later part of my career.

In Depth Look at Soil Analysis & Paper

In Depth Look at Soil Analysis & Paper

J: You recently published a paper on analyzing ammonium-nitrate-nitrogen KCl extracts of Georgia soils. Can you tell us more about that?

U: KCl extracts of soil has been used by the scientist or soil fertility people to determine the nitrogen fertility of soil, which is very dynamic. And generally, people do it multiple times during a cycle to see the nitrogen status. The KCl extracted ammonium nitrogen and nitrate nitrogen are of interest in this context, which are readily available for plants. So there are two things that I actually addressed in the paper.

Traditionally the recommendation is to use a -2M KCl extract and that has been in practice for a long, long time. So one of the goals was whether 2M KCl is really needed or whether a dilute version can be equally effective. Also whether this strong -2M KCl, is really required for all types of soil. Say for example some soils, which are rich organic matter and clay that has high CEC (cation exchange capacity), or attraction ability, that may need a stronger KCl to release the adsorbed ammonium and nitrate but for many light textured low organic matter soils that may not be necessary.

So one of the things we addressed in the paper is the effect of various levels of KCl. In other words we used various concentrations of KCl extractant and evaluated the amount of ammonium and nitrate nitrogen extracted by those solutions. So one of the findings of the paper was that 2M KCl is really not necessary. A more dilute version, down to even 0.2M or 0.5M, can be as effective as 2M KCL.

The other thing that we did in the paper is that we compared the measurement of ammonium and nitrate nitrogen in the KCL-extracts of soils by the diffusion/conductimetric method and compared it with the conventional method of distillation/titration. What we found is that the ammonium -and nitrate nitrogen extracted by KCl from various Georgia soils can be measured by the diffusion conductivity method, which can produce comparable results as given by distillation/titration with an error level of plus/minus ten percent. So this result has been greatly impactful because distillation/titration is a very troublesome method. And we do one sample at a time, as such it is time consuming, it requires a good number of chemicals and is subjected to more human error. Whereas the diffusion conductivity method that produced comparable results is rapid, cheap, and less troublesome. It’s pretty epic because you can set up numerous samples on the auto-sampler tray, walk away, and we can get comparable results.