Technology & Digital Tools Flashcards

Which remote sensing technique measures the time delay of returning laser pulses to calculate precise tree heights across a landscape?

Answer: LiDAR (Light Detection and Ranging)

LiDAR emits laser pulses and measures return travel time to calculate precise 3D point cloud data including canopy and ground heights.

A forester is analyzing a timber harvest plan and needs to calculate the volume of wood in a stand delineated as a GIS polygon. Which approach best integrates GIS and inventory data?

Answer: Joining inventory cruise data to the GIS stand polygon by stand ID and applying per-acre volume factors

Joining cruise data to stand polygons via a shared stand ID allows per-acre volume estimates to be scaled by GIS-calculated stand area.

Which federal program provides free, publicly available LiDAR-derived elevation products for the United States?

Answer: 3DEP (3D Elevation Program) via The National Map

USGS 3DEP collects and distributes LiDAR-based elevation data including DEMs, point clouds, and derived products through The National Map.

In forest management software, what is a 'stand simulation' used for?

Answer: Projecting how stand characteristics (basal area, volume, species composition) will change over time under different management scenarios

Stand simulation projects future stand conditions using growth models to compare outcomes of different harvesting or silvicultural treatments.

What is the main purpose of a mobile forest inventory app (e.g., Collector for ArcGIS, TerraSync) compared to paper-based cruising?

Answer: It enables GPS-tagged data capture that integrates directly with GIS databases, reducing transcription errors

Mobile apps capture field data with GPS coordinates and sync to databases, reducing manual transcription errors and post-processing time.

A forester notices that a classified land cover map shows forests in areas known to be clearcuts. Which step in the remote sensing workflow most likely caused this error?

Answer: Image acquisition during leaf-off season causing spectral confusion

Leaf-off imagery can cause recently harvested areas to appear spectrally similar to forest due to residual slash or dormant understory vegetation.

Which technology allows a forester to measure tree diameters from the ground without physical contact using laser-based ranging?

Answer: Terrestrial LiDAR scanning (TLS) or laser dendrometers

Terrestrial LiDAR scanners or laser dendrometers use time-of-flight or phase-based ranging to measure stem diameters without touching the tree.