HNSE-P4-7. Determining Organic Content in Soil from the Mojave Desert using Loss-on-Ignition
Faculty Mentor: Scott Abella, Ph.D.1
1College of Sciences, School of Life Sciences
Measuring the soil organic carbon (SOC) is of vital importance to soil science ecology. With the approaching challenges that rapidly changing weather patterns and temperatures bring, it is becoming more important to be able to measure the organic carbon levels in soil quickly, accurately, and cheaply. Currently, existing methods can very accurately deduce organic carbon levels but are lacking in speed and cost. Using alternate methods such as Loss-On-Ignition (LOI) can make up for lacking speed and affordability and have been shown to be very accurate under the right conditions. Ultimately, having a secondary method to quickly and easily get rather accurate results could be useful to preliminary investigations. The primary objective is to use LOI to accurately estimate the soil organic compound levels of low-elevation Mojave Desert soil. Using soils that were collected from wildfires spanning 15-20 years old, LOI procedures were tested using a factorial design including crucible size, temperature, and time. Using 5 mL crucibles, temperatures ranging from 300 to 600°C and time periods ranging from 2 to 8 h were used in different combinations to obtain the best results. The r2 values were examined for these factorial combinations to determine the most convenient and accurate combination. The results showed that 600 °C at 6 hours had the best results, with an r2 of 0.602. As these are just preliminary results, running a set with a much larger sample size must be done to ensure that the results are consistent.
This research was funded by the Southern Nevada Northern Arizona (SNNA) Louis Stokes Alliance for Minority Participation (LSAMP), which is housed within UNLV’s Center for Academic Enrichment and Outreach and supported by a grant (HRD – 1712523) from the National Science Foundation (NSF). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the NSF.