FOR 474: Forest Inventory. FOR 474: Forest Inventory. Why do we Care About Forest Sampling?

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1 FOR 474: Forest Inventory 1. Advanced Forest Inventory The Need for Forest Sampling Brief Intro to Remote Sensing and GIS Readings: FOR 474: Forest Inventory Related Courses! FOR 274: Forest Measurements REM 410: Range Measurements NR 402: GIS in Natural Resources Stats 422: Sample Survey Methods FOR 472: Remote Sensing FOR 570: Grad Remote Sensing Why do we Care About Forest Sampling? Forest managers are required to make important decisions relating to numerous (sometimes competing) resources. Ideally such decisions would be based off an inventory of all the organisms, but cost, feasibility, and timing make this rare As such, we must make decisions based off only a small portion, or sample, of the data. 1

2 Why do we Care About Forest Sampling? Questions that this course will help answer: How can we use LiDAR in forest inventory assessment? What are the limitations of LiDAR? What do we do when data is missing? How can we make management decisions? Why Are Forest Inventories not Tree-Based? Example: Assume in this forest we want to quantify the board feet of all PIPO >15 DBH Problems: - Many many trees will meet this requirement - These trees will likely be widely and irregularly dispersed It will not be practical to develop a sampling protocol where each PIPO was a sampling unit Panhandle NF D Taylor Why Are Forest Inventories not Tree-Based? Timber estimation is rarely done with the individual tree as the sampling unit. This is why Plots & Stands are used. Panhandle NF D Taylor 2

3 The Forest: An Aerial Perspective The Forest: An Aerial Perspective Message of the Day: Analysis of aerial photography can enable us to assess a whole stand with no field measurements What is Not Remote Sensing? Definition of a Geographic Information System (GIS): A system for capturing, storing, checking, integrating, manipulating, analyzing, and displaying data which are spatially referenced to the Earth. : 3

4 Remote Sensing: Overview Campbell, 1996: Remote sensing is the science of obtaining information about an object from measurements made at a distance from the object (i.e. without touching the object). Remote Sensing of the Earth frequently measures electromagnetic radiation in one or more regions of the electromagnetic spectrum. This radiation can be reflected or emitted from the earth's surface. Remote Sensing: Overview Wildlife Management Hazard Assessment Remote Sensing: Overview Remote sensing is the science of obtaining information about an object from measurements made at a distance from the object (i.e. without touching the object). 4

5 Remote Sensing: Overview Spatial Resolution High Low Remote Sensing: Overview Extent Low High Remote Sensing: Overview Spectral Resolution 5

6 Geology and Terrain Modeling Volcanoes of Mars Nevada surface materials map from AVIRIS imagery: Source: USGS Seeing Beneath Trees with Lidar Agriculture Non-Ag Vegetation: Land Use/Change, Carbon, Disturbances 6

7 Atmospheric Sciences Hurricane Alleta Oceanic Sciences Phytoplankton Sea Surface Temperatures Urban 7

8 Water, Ice, and Snow Baffin Bay, Greenland ASTER: Glaciers Retreating The Forest: Lets Start With Aerial Photographs! Aerial Photographs: Overview Airphoto acquisition Airphoto interpretation etat Cartographic/GIS Analysis Data to Users 8

9 Aerial Photographs: Overview Photo Lens P field of view Tilted Photo P Lens field of view 90 o a) Vertical aerial photography Optical axis 90 o b) low oblique Aerial Photographs: Overview Radial Displacement Aerial Photographs: Overview Stereoscopy The science of perceiving depth (and thus height) with two eyes/vantage points 9

10 Aerial Photographs: Assessments Visual Association: we can identify trees and rivers and thus use expert knowledge to infer what species are likely to occur near the river. Aerial Photographs: Assessments Pattern and Shape: we can identify trees by their branches Aerial Photographs: Assessments Pattern and Shape: we can also identify natural forests from human generated environments 10

11 Aerial Photographs: Assessments Color and Tone: we can easily separate conifers (dark) from hardwoods in winter or early spring Aerial Photographs: Assessments Color and Tone in Infrared Film: we can easily separate conifers from hardwoods as hardwoods reflect more infrared radiation and so appear brighter Aerial Photographs: Assessments Texture: can easily separate conifers (rough) from hardwoods (smooth) Mature Conifer Stand Conifers Hardwoods 11

12 Aerial Photographs: Assessments Color and Tone in Infrared Film: we can easily separate healthy trees as they appear red and diseased trees appear green LiDAR for Operational Forest Management Next Week 12