Forest metrics derived from the 2008 Lidar point clouds, includes canopy closure, percentile height, and stem mapping for the Andrews Experimental Forest.

There are three types of forest metrics within this database. They all are derived from the raw Lidar point clouds using the FUSION software. The three types are canopy closure, height metric, and stem mapping. The canopy closure and height metric grids cover a variety of canopy heights and grid cell sizes.

1. Canopy closure: This metric measures the canopy closure of a given horizontal cell above a given vertical threshold (height break). Canopy closure can inform many landscape models and provide insight on how much light will reach the forest floor.
2. Height Metric: This metric measures the height at which a given percent of the first return points are below. This analysis is done in a given grid cell size. Height metrics give various statistics of the elevation above ground for a given set of Lidar points. In forested landscapes, first return height metrics describe the forest canopy.
3.This stem map locates the approximate center of all trees in the HJ Andrews Research Forest greater than 10 meters. In addition to the stem location, a canopy radius is also provided.

FUSION and TreeVaWA software programs were used to develop this data.

Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data from HJ Andrews and the Willamette National Forest (NF) on August 10th and 11th 2008. Total area for this AOI is 17,705 acres. The total area of delivered LiDAR including 100 m buffer is 19,493 acres.

本数据库包含三类森林遥感指标，均通过FUSION软件从原始激光雷达（LiDAR）点云数据处理得到，具体为冠层覆盖率、高度指标与树干映射三类。冠层覆盖率与高度指标栅格涵盖了多种冠层高度及栅格单元尺寸。
1. 冠层覆盖率：该指标用于测算给定水平栅格单元内，高于指定垂直阈值（高度断点）的冠层占比。冠层覆盖率可为诸多景观模型提供参考，并可用于分析到达林床的光照量。
2. 高度指标：该指标用于统计给定百分比的首次回波点云的高程值，分析基于指定栅格单元开展。高度指标可给出给定激光雷达点云集合的地面以上高程统计量；在森林景观中，首次回波高度指标可表征森林冠层结构。
3. 树干映射：该数据集用于定位HJ安德鲁斯研究林区内所有树高超过10米的树木的近似中心位置。除树干位置外，还提供了冠层半径信息。
本数据集由FUSION与TreeVaWA两款软件开发完成。
2008年8月10日至11日，Watershed Sciences, Inc.（WS）于HJ安德鲁斯研究区及威拉米特国家森林（NF）采集了激光雷达（LiDAR）数据。本次研究感兴趣区域（Area of Interest，AOI）总面积为17705英亩，包含100米缓冲区的交付激光雷达数据总面积为19493英亩。