Hiking Trails Facilitate the Spread of a Native High-Arctic Species.

High-Arctic environments are facing an elevated pace of warming and increasing human activities, making them more susceptible to the introduction and spread of alien species. We investigated the role of human disturbance in facilitating the spread of a native plant () in a high-Arctic natural environment close to Isfjord Radio station and along adjacent hiking trails at Kapp Linné, Svalbard. We reconstructed the spatial pattern of the arrival and spread of at Kapp Linné by combining historical records of the species occurrence (1928-2018) with a contemporary survey of the plant abundance along the main hiking trail (2023 survey) and tested the relative effects of altitude and proximity to hiking trails on the species density via a generalised linear model (GLM).

A case study on the application of spore sampling for the monitoring of macrofungi.

Fungi play a vital role in ecosystem functioning, yet significant knowledge gaps persist in understanding their diversity and distribution leading to uncertainties about their threat status and extinction risk. This is partly owed to the difficulty of monitoring fungi using traditional fruiting body surveys. The present study evaluates airborne environmental DNA (eDNA) sampling as a monitoring tool with a focus on grassland macrofungi.

Response to Comment on "Increased growing-season productivity drives earlier autumn leaf senescence in temperate trees".

Our study showed that increases in seasonal productivity drive earlier autumn senescence of temperate trees. Norby argues that this finding is contradicted by observations from free-air CO enrichment (FACE) experiments, where elevated CO has been found to delay senescence in some cases. We provide a detailed answer showing that the results from FACE studies are in agreement with our conclusions.

Increased growing-season productivity drives earlier autumn leaf senescence in temperate trees.

Changes in the growing-season lengths of temperate trees greatly affect biotic interactions and global carbon balance. Yet future growing-season trajectories remain highly uncertain because the environmental drivers of autumn leaf senescence are poorly understood. Using experiments and long-term observations, we show that increases in spring and summer productivity due to elevated carbon dioxide, temperature, or light levels drive earlier senescence.