Increased deadwood carbon stocks through planted forestry practices: insights from a Forest Inventory Survey in Japan

Abstract

Deadwood, a vital component of forest ecosystems, constitutes a quintessential carbon reservoir that must be disclosed under the United Nations Framework Convention on Climate Change. This reservoir, comprising fallen logs, snags, and stumps, markedly affects carbon dynamics over decades. In this study, deadwood carbon stocks were quantified using data from 2674 sites in Japan surveyed between 2011 and 2015 via the National Forest Soil Carbon Inventory, and the deadwood carbon attributes in the country were explored. Deadwood were surveyed using the line intersect method for fallen logs and the belt transect method for stumps and snags. In Japan, the deadwood carbon stock (measured in t-C/ha) was quantified at 7.5 ± 9.74 (mean ± SD), with fallen logs at 3.26 ± 4.43, stumps at 2.45 ± 5.69, and snags at 1.80 ± 5.27, with significant differences detected among these stocks (p < .001). Considering deadwood carbon accumulation in Japan, planted forests exhibited a significantly larger (p < .001) deadwood carbon stock than natural forests. Moreover, planted forests exhibited a higher proportion of fallen logs than snags and stumps, indicating the effects associated with logs left on forest floors after thinning. Based on these findings, deadwood carbon stocks have the potential to bolster the validation and refinement of computational models used in carbon accounting.

Keywords:

• Deadwood
• carbon stock
• national forest soil carbon inventory
• climate change
• conifer

Acknowledgments

This research is the outcome of the National Forest Soil Carbon Inventory (NFSCI) conducted and supported by the Forestry Agency in Japan. This work was supported by the JSPS KAKENHI under Grant Number JP22H02400. We thank the various sampling and analysis companies for their cooperation in collecting and analyzing soil samples. We are also grateful to the Forest Soil Division at the Forestry and Forest Products Research Institute for generating dependable and advanced datasets. In particular, we wish to express our sincere gratitude to Dr. Toru HASHIMOTO and Dr. Yoshiyuki INAGAKI for their expert validation of deadwood data. We also thank Dr. Kazuhito MORISADA, Dr. Nagaharu TANAKA, and Dr. Hisao SAKAI for their cooperation and advice regarding this research.

Disclosure statement

The authors report there are no competing interests to declare.

Data availability statement

Data are not available – access to data is restricted because the data is under government jurisdiction and control.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was supported by JSPS KAKENHI.