Influence of Natural and Anthropogenic Linear Canopy Openings on Forest Structural Patterns Investigated Using LiDAR

Udayalakshmi Vepakomma,Louis De Grandpré,Daniel Kneeshaw

doi:10.3390/f9090540

Udayalakshmi Vepakomma, Louis De Grandpré + Show 1 more

Open Access

https://doi.org/10.3390/f9090540

Copy DOI

Abstract

In much of the commercial boreal forest, dense road networks and energy corridors have been developed to access natural resources with unintended and poorly understood effects on surrounding forest structure. In this study, we compare the effects of anthropogenic and natural linear openings on surrounding forest conditions in black spruce stands (gap fraction, tree and sapling height, and density). Forest structure within a 100 m band around the edges of anthropogenic (roads and power lines), natural linear openings (streams), and a reference black spruce forest was measured by identifying individual stems and canopy gaps on recent high density airborne LiDAR canopy height models. CUSUM curves were used to assess the distance of edge influence. Forests surrounding anthropogenic openings were found to be gappier, less dense, and have smaller trees than those around natural openings. Forests were denser around natural and anthropogenic linear openings than in the reference forest with edge effects observed up to 24–75 m and 18–54 m, respectively, into the forest. A high density of saplings in the gappier forests surrounding anthropogenic openings may eventually lead to a higher forest biomass in the zone area surrounding roads as is currently observed around natural openings.

Highlights

As a consequence of the rapid increase in forest management and resource extraction, an increase in the abundance of narrow-linear canopy openings such as roads, powerlines, oil and gas pipelines, etc. can be observed over the past century in forested areas throughout the world [1]
We evaluated the influence of linear openings on forest structure as measured by canopy gaps, sapling height and density, and tree height and density along a 100 m wide forest band
Forest structure significantly differed in the neighborhood of linear openings compared to the reference forest

Summary

Introduction

As a consequence of the rapid increase in forest management and resource extraction, an increase in the abundance of narrow-linear canopy openings such as roads, powerlines, oil and gas pipelines, etc. can be observed over the past century in forested areas throughout the world [1]. As a consequence of the rapid increase in forest management and resource extraction, an increase in the abundance of narrow-linear canopy openings such as roads, powerlines, oil and gas pipelines, etc. Road networks criss-cross much of the temperate and boreal forest regions. In order to understand their overall impact on the forest, it is necessary to evaluate the distance of influence of edge effects from these openings. Earlier studies have reported a large array of distance effects from edges ranging from tens to thousands of meters depending on the metric evaluated and the study region [5,6,7]. Linear openings have a high edge to area ratio which given their omnipresence should lead to large effects across vast managed forest regions

Methods

Results

Discussion

Conclusion