Eucalyptus plantation age and species govern soil fungal communities under marginal tropics climate

In total, six plantations with ca. 2.2 ha per plantation were selected representing three Eucalyptus species (E.urophylla×E.grandis (EUG), E. camaldulensis (EC) and E. pellita (EP)) with different ages (1-year-old, 5-year-old or 11-year-old). Each of the three species had 1-year-old (EUG1y, EC1y and EP1y) and 5-year-old (EUG5y and EC5y) plantations, except for EP with 11-year-old (EP11y) plantation. The symbol of 5+-year-old plot thereafter was used to refer to 5-year (EUG5y and EC5y) and 11-year (EP11y) plantations. In each plantation, three subplots (15 m × 15 m) were selected randomly, in which three trees were chosen randomly per subplot for sampling. After the litter removal, three soil cores (100 cm3) around each tree were collected at a depth of 0–10 cm from three directions with 120°and then mixed as one sample, resulting 9 samples per plantation and 54 samples in total. The samples were put into carry-on ice box immediately and delivered to the laboratory. All the soil samples were taken on the same day in rain season on May 18th 2017.

共计选取6个人工林样地，每个样地面积约2.2公顷，涵盖3种桉树：尾叶桉×巨桉（E.urophylla×E.grandis，缩写EUG）、赤桉（E. camaldulensis，缩写EC）和佩利桉（E. pellita，缩写EP），各林分的年龄分别为1年生、5年生或11年生。3个桉树物种均设置有1年生（EUG1y、EC1y、EP1y）和5年生（EUG5y、EC5y）人工林样地，仅佩利桉（EP）额外设置了11年生（EP11y）人工林样地。后续将以“5年生及以上样地”作为统称，指代5年生的EUG5y、EC5y以及11年生的EP11y人工林样地。在每个人工林样地内，随机选取3个15m×15m的小样方，每个小样方中再随机选取3株林木用于采样。去除地表凋落物后，在每株林木周围以120°夹角的三个方向，采集0~10cm深度、容积为100cm³的土芯3份，将其混合为1份土壤样品；每个人工林样地可获得9份样品，总计54份样品。采集完成的样品立即装入便携冰盒，并转运至实验室。所有土壤样品均于2017年5月18日的雨季当日完成采集。