Filtering ground noise from LiDAR returns produces inferior models of forest aboveground biomass

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# About Me

- Lucas Johnson

- Ph.D. Student at SUNY-ESF

- Focusing on mapping forest structure across New York State

- Background in machine learning, computer science

- https://www.lucaskjohnson.com/

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## New York State 2019 CLCPA:

### • 85% Reduction in GHG emissions by 2050

### • Net zero emissions statewide by 2050

### • Lands & forests make up the difference

### • Need ways to track forest C sequestration

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<p style="font-size:8px">Figure from Shirer, R. and Zimmerman, C. (2010) Forest Regeneration in New York State. The Nature Conservancy.</p>

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# Objective 1:

### Does filtering ground noise help us model AGB?

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# Objective 2:

### Does ground noise filtering matter more in mixed-use landscapes?

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## Our approach:

### • Filter LiDAR using 5 height thresholds

### • Fit random forests to each predictor set

### • Compare model performance

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## Key Takeaways:

### • Ground noise filtering doesn't help and sometimes hurts AGB models

### • Impacts are greater in patchier, less-forested landscapes

### • Ground noise filtering should be avoided when modeling AGB

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# Thank you!

This work was financially supported by the Climate & Applied Forest Research Institute at SUNY-ESF.

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#### Preprint:
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