Author(s)

Felix Seidel^1,2, M. Larry Lopez C^1*, Georg Guggenberger², Yoshihiro Nobori¹

¹Faculty of Agriculture, Yamagata University, Yamagata, Japan.
²Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany.

Slash and burn practices are widely used around the globe with different degrees of success which are mostly related to the impact of fire on soil properties. In Japan slash and burn practises, known as Yakihata, have a long history and are still used in Yamagata Prefecture today. The purpose of this study was to determine the impact of a low severity controlled fire underneath Japanese cedar (Cryptomeria japonica) on brown forest soil (Cambisol). Japanese Cedar is the dominant species among plantations in Japan. We measured organic carbon and nitrogen content as well as changes in carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope composition in a steep west facing slope under heavy precipitation (~2600 mm/a) and heavy snowfall (~3 to 4 m/a). The accumulation of C_total and N_total at the bottom of the slopes was remarkably higher at the slash and burned site than in the control forest site. After slash and burn δ1⁵N isotopes in the slope in general became significantly lighter than in the control forest while the δ¹³C did not show any significant difference between the two sites except at the bottom of the slopes where δ¹³C was heavier in the forest. The results show that C_total and N_total values as well as the isotopes ratios of C and N change with decreasing elevation in the forest as well as in the burned site being consistent with leaching and erosion. The changes in soil nitrogen and carbon isotopes at the bottom of the slope appear to be related to the transport of material with different isotopic composition from the upper slope. The effect of the low severity fire (as part of the slash and burn practice) on soil organic carbon and nitrogen movement was enhanced by the steepness of the slopes and the high precipitation of Shonai region.

High Precipitation, Japanese Cedar Forest Soil, Low Severity Fire, Stable Isotopes, Steep Slopes

Seidel, F. , Lopez C, M. , Guggenberger, G. and Nobori, Y. (2017) Impact of a Low Severity Fire on Soil Organic Carbon and Nitrogen Characteristics in Japanese Cedar Soil, Yamagata Prefecture, Japan. Open Journal of Forestry, 7, 270-284. doi: 10.4236/ojf.2017.72017.