Dr. Judith K. Turk
Date of this Version
The world’s population is growing and an increasing populace requires more resources. These requirements place increasing pressure on the environment and the soil. Soils serve many important functions throughout the world. These functions range from offering a media for food production, providing a sink for organic carbon, nutrient cycling, and improving water quality. It is important to focus on the human impact on soils and their change over time.
For my research I examined how soils across Nebraska have changed over a time period of roughly 65 years. I sampled and analyzed 39 pedons from four Major Land Resource Areas (MLRAs) across the state of Nebraska. These sites were selected because they each represent a distinctive combination of climate, geology, and land use within Nebraska. At the time of original sampling (1951- 1961), nearly all the sites were under row-crop production. I created a correlation for estimating soil organic carbon for four MLRAs using loss-on-ignition organic matter values. Next, I examined how the soils in MLRAs 67 and 71 have changed over 65 years of continued irrigation and agricultural production. Lastly, I assessed how the soils MLRAs 106 and 107 have changed after 65 years of non-irrigated agricultural production.
Advisor: Judith K. Turk