scholarly journals Quantifying Boreal Forest Structure and Composition Using UAV Structure from Motion

Forests ◽  
2018 ◽  
Vol 9 (3) ◽  
pp. 119 ◽  
Author(s):  
Michael Alonzo ◽  
Hans-Erik Andersen ◽  
Douglas Morton ◽  
Bruce Cook
Keyword(s):  
Boreal Forest ◽  
Structure From Motion ◽  
Forest Structure

Understory biomass estimation based on Structure from Motion data by Multi-layered forest drone survey

2021 ◽  
Author(s):  
Yupan Zhang ◽  
Yuichi Onda ◽  
Hiroaki Kato ◽  
Xinchao Sun ◽  
Takashi Gomi
Keyword(s):  
Structure From Motion ◽  
Forest Structure ◽  
Large Scale ◽  
Forest Canopy ◽  
Point Clouds ◽  
Understory Vegetation ◽  
Biomass Estimation ◽  
Canopy Openness ◽  
Cubic Model ◽  
Overlap Analysis

<p>Understory vegetation is an important part of evapotranspiration from forest floor. Forest management changes the forest structure and then affects the understory vegetation biomass (UVB). Quantitative measurement and estimation of  UVB is a step cannot be ignored in the study of forest ecology and forest evapotranspiration. However, large-scale biomass measurement and estimation is challenging. In this study, Structure from Motion (SfM) was adopted simultaneously at two different layers in a plantation forest made by Japanese cedar and Japanese cypress to reconstruct forest structure from understory to above canopy: i) understory drone survey in a 1.1h sub-catchment to generate canopy height model (CHM) based on dense point clouds data derived from a manual low-flying drone under the canopy; ii) Above-canopy drone survey in whole catchment (33.2 ha) to compute canopy openness data based on point clouds of canopy derived from an autonomous flying drone above the canopy. Combined with actual biomass data from field harvesting to develop regression models between the CHM and UVB, which was then used to map spatial distribution of  UVB in sub-catchment. The relationship between UVB and canopy openness data was then developed by overlap analysis. This approach yielded high resolution understory over catchment scale with a point cloud density of more than 20 points/cm<sup>2</sup>. Strong coefficients of determination (R-squared = 0.75) of the cubic model supported prediction of UVB from CHM, the average UVB was 0.82kg/m<sup>2</sup> and dominated by low ferns. The corresponding forest canopy openness in this area was 42.48% on average. Overlap analysis show no significant interactions between them in a cubic model with weak predictive power (R-squared < 0.46). Overall, we reconstructed the multi-layered structure of the forest and provided models of UVB. Understory survey has high accuracy for biomass measurement, but it’s inherently difficult to estimate UVB only based on canopy openness result.</p>

Rehabilitating boreal forest structure and species composition in Finland through logging, dead wood creation and fire: The EVO experiment

2007 ◽  
Vol 250 (1-2) ◽  
pp. 77-88 ◽  
Author(s):  
I. Vanha-Majamaa ◽  
S. Lilja ◽  
R. Ryömä ◽  
J.S. Kotiaho ◽  
S. Laaka-Lindberg ◽  
...  
Keyword(s):  
Species Composition ◽  
Boreal Forest ◽  
Forest Structure ◽  
Dead Wood

scholarly journals Estimating Mangrove Forest Volume Using Terrestrial Laser Scanning and UAV-Derived Structure-from-Motion

Drones ◽  
2019 ◽  
Vol 3 (2) ◽  
pp. 32 ◽  
Author(s):  
Angus D. Warfield ◽  
Javier X. Leon
Keyword(s):  
Structure From Motion ◽  
Forest Structure ◽  
Mangrove Forest ◽  
Laser Scanning ◽  
Terrestrial Laser Scanning ◽  
Cost Effective ◽  
Stand Age ◽  
Stem Density ◽  
Aerial Vehicle ◽  
Non Destructive

Mangroves provide a variety of ecosystem services, which can be related to their structuralcomplexity and ability to store carbon in the above ground biomass (AGB). Quantifying AGB inmangroves has traditionally been conducted using destructive, time-consuming, and costlymethods, however, Structure-from-Motion Multi-View Stereo (SfM-MVS) combined withunmanned aerial vehicle (UAV) imagery may provide an alternative. Here, we compared the abilityof SfM-MVS with terrestrial laser scanning (TLS) to capture forest structure and volume in threemangrove sites of differing stand age and species composition. We describe forest structure in termsof point density, while forest volume is estimated as a proxy for AGB using the surface differencingmethod. In general, SfM-MVS poorly captured mangrove forest structure, but was efficient incapturing the canopy height for volume estimations. The differences in volume estimations betweenTLS and SfM-MVS were higher in the juvenile age site (42.95%) than the mixed (28.23%) or mature(12.72%) age sites, with a higher stem density affecting point capture in both methods. These resultscan be used to inform non-destructive, cost-effective, and timely assessments of forest structure orAGB in mangroves in the future.

Forest structure and composition at young fire and cut edges in black spruce boreal forest

2004 ◽  
Vol 34 (2) ◽  
pp. 289-302 ◽  
Author(s):  
Karen A Harper ◽  
Daniel Lesieur ◽  
Yves Bergeron ◽  
Pierre Drapeau
Keyword(s):  
Species Composition ◽  
Boreal Forest ◽  
Forest Structure ◽  
Black Spruce ◽  
Cumulative Effect ◽  
Mean Values ◽  
Clear Cutting ◽  
Interior Forest ◽  
Edge Influence ◽  
Range Of Variation

We compared structure and composition at forest edges created by wildfire and clear-cutting in black spruce (Picea mariana (Mill.) BSP) dominated boreal forest in northwestern Quebec. Forest structure and plant species composition were sampled along transects perpendicular to eight 3- to 4-year-old fire edges and eight 2- to 5-year-old cut edges. Significance of edge influence was assessed by comparing mean values at different distances from the edge to the range of variation in interior forest. The influence of clearcut edges was minimal, generally extending only 5 m from the edge, and included greater log density and different species composition, compared with interior forest. At fire edges, prominent responses to edge creation included increased snag density and lower moss cover, compared with interior forest, extending up to 40 m into the forest. This initial structural change was likely due to partial burning extending into the forest. Overall, fire edges had more snags and a different species composition than cut edges. Our hypothesis that edge influence is more extensive at fire edges than at cut edges was supported for overstory and understory structure, but not for species composition. We suggest that there is a need for management to consider the cumulative effect of the loss of fire edges on the landscape.

Sign in / Sign up

Export Citation Format

Share Document