Soil Health Gap — a concept to establish a benchmark for soil health management |

Soil Health Gap — a concept to establish a benchmark for soil health management

Nebraska Extension

Saurav Das appointed research associate in soils program at Panhandle Center

Bijesh Maharjan has been building his soil research and extension program for several years at the Panhandle Research and Extension Center in Scottsbluff. Now, Maharjan’s program has grown with the addition of Saurav Das, appointed as a research associate in soil health.

“Saurav has a background in microbiology, so with a big push on soil health, he will be a good fit in the soils program,” Maharjan said. Das will be involved in projects to do with soil health, including developing potential funding proposals and monitoring graduate students and interns. He also helped organize the first Panhandle Soil Health workshop in early March.

Maharjan said soil health is an important topic, and a number of land-grant universities have faculty soil health posts.

The Panhandle Center has a unique soil laboratory in the Knorr-Holden Corn Plot, established in 1912. The Knorr-Holden plot is one of the five oldest continuous field crop experiments in the United States, and is the oldest irrigated corn plot. It has been listed in the National Register of Historic places since 1992, one of three such designations in the United States for long-term research plots. Das has helped collect 100 years of data from Knorr-Holden and will submit it for publication.

Das said he is working on developing the baseline data on soil health. “The soil has degraded since the beginning of agriculture, when it was grass and virgin fields, and can we change practices or use amendments to restore it to close to its original status,” he said.

Prior to joining Maharjan’s soils program, Das spend 11/1 years as a visiting scientist with Dipak Santra’s alternative crops breeding program, working on field peas and and proso millet.

He attended college and received degrees in India, including a master’s in biotechnology and Ph.D. in microbiology. His studies involved the biogeochemical cycle of arsenic and factors affecting it. After receiving his Ph.D. he worked as an adjunct faculty member in water quality, researching and teaching about the distribution of antibiotic resistant pathogens in water, and how it affects human health.

Soil health advocates say interest is growing in nurturing the health of the vital natural resource. But there’s no standard way to measure soil health or predict its potential for improvement.

Now, a soil scientist at the University of Nebraska-Lincoln is proposing a name and a concept that could help establish the parameters for measuring baseline soil health and its potential for improvement.

Soil Health Gap is the term coined by Bijesh Maharjan, soil nutrient and management specialist at the University of Nebraska-Lincoln Panhandle Research and Extension Center in Scottsbluff. It is also the topic of an article that Maharjan has co-authored and published in the online journal Global Ecology and Conservation.

The article defines Soil Health Gap as the “difference between soil health in an undisturbed native virgin soil and current soil health in a cropland in a given agroecosystem.” Maharjan’s co-authors are Saurav Das, research associate in Maharjan’s soils program in Scottsbluff, and Bharat Sharma Acharya of the Oklahoma Department of Mines.

The article is online at

Maharjan is hoping that the soil health gap concept is a framework that he and his colleagues around the nation can use, refine, and continue to develop. Already, he says Soil Health Gap is being discussed widely, including on social media, and used as a concept in grant proposals to fund future research.

Maharjan and his co-authors describe the need for a common approach: “Growing calls and the need for sustainable agriculture have brought deserved attention to soil and to efforts towards improving or maintaining soil health,” they write. But a lack of benchmarks that are relevant and specific to site and soil properties limits research efforts to measuring soil health in terms of physicochemical and biological indicators, and then identifying management practices that could improve it.

The lack of benchmarks leaves some key questions unanswered: How much of cultivated land has degraded since the dawn of agriculture? What is the maximum or realistically attainable soil health goal? “Determination of a benchmark that defines the true magnitude of degradation and simultaneously sets potential soil-health goals will optimize efforts in improving soil health using different practices.”

Maharjan and his co-authors suggest that Soil Health Gap can be determined based on either general or specific soil properties, such as soil carbon levels or aggregates (the physical particles that make up soil). “Scientific advancement in identifying primary soil health indicators and developing soil health index based on (these indicators) is key to a reliable and quantitative measure of soil health.”

The benchmark can be scaled up from site-specific, to regional, to global scale. “Information on soil health gap, on a local or broader scale, can help identify areas with the greatest potential to enhance soil health, prioritize efforts, and invest resources effectively,” according to the article.

Ag producers are interested in the topic of soil health, according to Maharjan. He said he was pleased by the interest shown by attendees at the first Panhandle Soil Health workshop, which he organized in Bridgeport in early March. Maharjan’s article also has generated quite a bit of buzz among colleagues in the soil science field around the nation.

He said the article also has been discussed by members of the Nebraska Healthy Soils Task Force, a 15-member panel created by legislative act in 2019 and appointed by the governor, which is responsible for developing a comprehensive healthy soils initiative and action plan.

According to the chairman of the task force, Keith Burns of Bladen: “In the quest for improving our nation’s soils and agricultural productivity, knowledge is power. We are developing knowledge sets about best-management practices to improve soil health, but often we are unaware of just how degraded our soils are. The Soil Health Gap concept will be useful as a benchmark to help determine appropriate soil health management decisions and realistic goals and timelines.”

Aaron Hird, USDA NRCS state soil health specialist, said: “The Soil Health Gap is a foundational concept of the measurement soil health. Providing a publicly available resource by which a standard measurement is established is a main focus at current times and is supported by the USDA Natural Resources Conservation Service, as it aligns with the agency mission and goals to support conservation work and improve soil health.

“The need for a common benchmark falls in line with other efforts and existing resources available from the NRCS, including Reference Sites established by existing Ecological Site Descriptions and future plans to expand the quantity of soil measures known about those reference sites throughout the nation,” according to Hird. “Establishing this Soil Health Gap concept is among the first step taken toward creating a common unit of measure and definitely falls in stride with many other concepts and work done or currently underway in every sector of soil health.”

The next step, says Maharjan, is to develop the concept further and encourage more focused research on soil health management. Up to this point, much of the research has consisted of trying different approaches and management strategies to improve soil health. “They have measured differences (in various soil parameters), but have no benchmark to indicate how high we can go,” Maharjan said. “So in that sense we are informing soil health management. Native soil might indicate what is possible.” ❖