Episodes 2019; 42(4): 313-319
Published online December 1, 2019
Copyright © International Union of Geological Sciences.
Woo-Jin Shin1, Insu Kim1, Jong-Sik Ryu1,2*, and Kwang-Sik Lee1
1Division of Earth and Environmental Sciences, Korea Basic Science Institute, Chungbuk 28119, Republic of Korea
2Department of Earth and Environmental Sciences, Pukyong National University, Busan 48513, Republic of Korea; *Corresponding author, E-mail: email@example.com
Correspondence to:*E-mail: firstname.lastname@example.org
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Many studies have used typical ranges of δ15N and δ18O values to identify nitrate sources. However, it is questionable whether typical nitrate isotopes for various sources can be universally applied. Thus, for inorganic (IOF), organic (OF) and plant-based compound fertilizers (PCF) in South Korea, δ15N and δ18O were measured to evaluate their commonly used ranges. The δ15N and δ18O were 2.6 ± 2.5‰ and 19.3 ± 2.6‰ (n = 19) for IOFs, 14.7 ± 7.7‰ and 5.9 ± 4.9‰ (n = 30) for OFs, and 10.9 ± 6.7‰ and 16.0 ± 6.1‰ (n = 24) for PCFs, respectively. Some OFs showed relatively lower δ15N than the previously reported values for NO3 fertilizers but all PCFs had both δ15N and δ18O similar to them, indicating that δ15N and δ18O for the organic material-based fertilizers were likely affected by both the composition level of the main ingredients and various additives in them. Dual isotopic data for three types of fertilizer in this study can play a crucial role in in-depth understanding the fate of natural and anthropogenic nitrate sources occurring in watershed.