Reconstruction of marimo population dynamics over 200 years using molecular markers and fossil plankton remains

Recent efforts have focused on reconstructing the historical abundance of unfossilized organisms using environmental DNA preserved in sediments (sedDNA). This information is crucial for understanding long-term changes in ecosystems. However, because sedDNA is prone to degradation, its quantification may not always provide accurate estimates of past abundances. To address this issue, we developed a novel method to correct for sedDNA degradation by incorporating plankton remains and applied it to estimate the historical abundance of marimo—large spherical colonies of the green alga Aegagropila brownie (formerly A. linnaei)—in Lake Akan, Japan, which is the only known habitat for large marimo. We first quantified marimo sedDNA in lake sediments dating back over 200 years. We then used our new method to estimate historical changes in their abundance from sedDNA. Analyses revealed that marimo were historically 10-100 times more abundant than they are today, but that their abundance declined ..., , , # Reconstruction of marimo population dynamics over 200 years using molecular markers and fossil plankton remains

## **Description of the data and file structure**

This folder contains the data for the article:

Authors: Jotaro Urabe, Isamu Wakana, Hajime Ohtsuki, Masayuki K. Sakata, Yurie Ohtake, Ryotaro Ichige, Michinobu Kuwae, Toshifumi Minamoto

Title: Reconstruction of marimo population dynamics over 200 years using molecular markers and fossil plankton remains.

Published in *Environmental DNA*

Comments and requests should be addressed to Jotaro Urabe: [[e-mail]](mailto:[e-mail]) or [[e-mail]](mailto:[e-mail])

When and where used, please cite this data set as Urabe, et al. (2025). Reconstruction of marimo population dynamics over 200 years using molecular markers and fossil plankton remains [Dataset]. Dryad. https://doi.org/10.5061/dryad.np5hqc03c

## File list

### **File name: Marimo\_data.csv**

Dataset used to reconstruct the marimo ...,