Assessing the potential of modern phytoliths to indicate variations in northern temperate forests- a case study from Northeast China

Abstract

Background and aims

The role of phytoliths as indicators of temperate forests remains a topic of ongoing debate that requires a clear understanding. This study aims to evaluate the potential of overall phytolith assemblages, as well as arboreal phytoliths, in representing the composition and abundance of temperate forests.

Methods

This study, conducted in Northeast China, established 79 sample plots across four forest types. Topsoil samples were collected, and corresponding vegetation data—including tree cover, grass cover, and the normalized difference vegetation index (NDVI)—were obtained from MODIS albedo products. Subsequently, we analyzed the significance of phytoliths in relation to various temperate forests.

Results

Results indicate that the P. koraiensis mixed forest, the P. koraiensis-Picea-Abies forest, the mountainous poplar-birch forest, and the Pinus-Quercus forest exhibit significantly different characteristics in their phytolith assemblage. Furthermore, these four forest types can be distinguished based on both overall phytoliths and arboreal phytoliths. However, phytoliths proved to be ineffective in accurately quantifying vegetation data in temperate forests, with forest NDVI demonstrating relatively better accuracy at 40%. Additionally, arboreal phytoliths contribute approximately 20% to the overall phytoliths used to indicate forest composition and abundance, and they exhibit a representation bias of 30-40% regarding tree abundance in temperate forests.

Conclusion

Our study highlighted the potential of utilizing overall phytoliths to differentiate various temperate forest types, while arboreal phytoliths were found to be more reliable indicators of forest abundance. Future work on north temperate forest phytolith should focus on establishing the quantitative relationship between phytoliths and forest abundance.