data.csv

This study was conducted in three permanent forest plots situated in the Changbai Mountain Nature Reserve, which is located in Jilin Province of northeastern China. The region is characterized with a typical continental mountain climate which is affected by the monsoon seasons. The mean annual temperature at the site was 3.6 ℃, with the an average monthly temperature ranging from a minimum of -15.4℃ in January to a maximum of 19.6℃ in August. The mean annual precipitation in the study was determined to be 707 mm, and the mean relative humidity was approximately 72%. The primary vegetation type was observed to be a broad-leaved Korean pine (<i>Pinus koraiensis</i>) mixed forest. The dominant species include <i>Pinus koraiensis</i>, <i>Tilia amurensis</i>, <i>Abies nephrolepis</i>, and<i> Acer pseudo-sieboldianum</i>. During the period of 2005 to 2007, three equally sized permanent plots were established as follows: A secondary conifer and broad-leaved mixed forest (CBF); a secondary poplar and birch mixed forest (PBF); and a mixed Tilia and Korean pine forest (TKF), respectively, as detailed in Table1. Each of the plots covered 5.2 hectare (260 × 200 m) and was divided into 130 quadrats of 20 × 20 m. All individuals with a diameter at the breast (DBH) ≥ 1 cm within the plots were identified, tagged, mapped, and measured. In this study’s analyses, only individuals with DBH ≥ 5 cm were included, since such trees were determined to account for almost all of the above-ground biomass (AGB) and productivity. In addition, all of the aforementioned plots were re-censused five years after being first established.