ABSTRACT
Leonardite is an important source of organic fertilizers and soil amendment. The objective of this study was to determine the effects of increased doses of leonardite (control (L0), 20 (L20), 40 (L40), 60 (L60), and 80 (L80) t ha−1) on soil properties at different incubation times (control (T0), 15 (T15), 30 (T30), 45 (T45), 60 (T60), and 90 (T90) days). Analysis results of soil samples taken during six different incubation periods. Results showed that application of leonardite significantly improved soil organic matter (SOM), total nitrogen (N), exchangeable calcium (Ca) and, available iron (Fe), manganese (Mn) and zinc (Zn), especially with L40 and L60. Prolonged incubation time was significantly increased N, P, K, Ca, Fe, Zn concentrations especially T60 and T90. The nutrient concentration of the tomato plants was not affected by increased doses of leonardite, except for total N, Fe and Cu. By the way, prolongation of the incubation period resulted in fluctuating nutrient concentrations of the plant. As a result, it was determined that leonardite improved the chemical properties of the soils but it was not sufficient in the feeding of the tomato plant. Therefore, leonardite must be used with chemical fertilizers for plant growing.
Acknowledgements
This study was financially supported by the Scientific Research Projects Coordination Unit of Akdeniz University (Grant no. FBA-2016-1799). Also, we would like to thank Erbil Demir, Nil Ozen and Ezgi Kilic for their contributions in the laboratory section of this work.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Correction Statement
This article was originally published with errors, which have now been corrected in the online version. Please see Correction (http://dx.doi.org/10.1080/00103624.2024.2337539)