University of Tasmania

File(s) under permanent embargo

Microclimatic edge effects in a recently harvested forest: do remnant forest patches create the same impact as large forest areas?

journal contribution
posted on 2023-05-18, 19:28 authored by Thomas Baker, Gregory JordanGregory Jordan, Susan BakerSusan Baker

Microclimatic forest influence (edge effects into open or regenerating areas) occurs within harvested forest, but the depth and magnitude may change depending on the design of the harvested area. This is an important consideration for managers, because gradients in microclimate can significant affect the ability of species to recolonise following disturbance. One harvesting method that can increase the amount of forest influence is aggregated retention. This technique involves leaving groups of trees (aggregates) within the harvested area, thus increasing the amount of regenerating forest that is near to an edge and therefore under forest influence. However, differences in the scale of forest influence generated from aggregates compared to unlogged forests surrounding harvested areas have not been tested. Understanding the ability of retained aggregates to generate forest influence is important in designing and implementing aggregated retention harvesting practices.

This study tested whether retained aggregates generated similar levels of forest influence as mature forest surrounding harvested areas. Microclimatic forest influence was examined by monitoring spatial changes in air temperature and relative humidity along transects running from within standing mature forest into harvested forest. Intact forest and aggregate transects were located in the direction of maximum expected forest influence (south-facing edges). Results showed that forest influence was mostly similar in both depth and magnitude regardless of the type of forest from which it was generated. Temporal examination of forest influence showed that it changed throughout the day and across the year, with peaks in magnitude occurring during the middle of the day, and in months close to the equinoxes. Shade derived from standing trees was a potential driver of temporal patterns in microclimatic forest influence.

At its peak magnitude, the microclimatic forest influence observed will likely have significant impacts on habitat suitability and thus, presumably, species recolonisation after disturbance. Results indicated that aggregated retention is an effective method for generating forest influence within harvested areas. Therefore, aggregated retention has the potential to be a valuable harvesting technique to alter microclimate and have beneficial impacts on the recovery of harvested forests.


Australian Research Council

Forestry Tasmania

Forests and Forest Industry Council of Tasmania


Publication title

Forest Ecology and Management








School of Natural Sciences


Elsevier Science Bv

Place of publication

Po Box 211, Amsterdam, Netherlands, 1000 Ae

Rights statement

Copyright 2016 Elsevier B.V.

Repository Status

  • Restricted

Socio-economic Objectives

Native forests

Usage metrics

    University Of Tasmania


    Ref. manager