New vegetation cover table to enable scaling Litterfall production

Data for the Litterfall and fine woody debris production and chemistry data product (DP1.10033.001) were published without data on total cover of qualifying vegetation (woody individual > 2M height). For sites with targeted trap placement, this resulted in an inability to scale litter production to plot or site levels. RELEASE-2024 (to be published in late January 2024) and releases and provisional data thereafter include a new table 'ltr_vegetationCover' that provides cover of qualifying woody vegetation at the scale of the subplot for all deployed traps at all sites (both targeted and random trap placement strategies). Total areal cover (m^2) and percent cover of vegetation >2m for all subplots/plots where litter traps are deployed is calculated from the LiDAR derived canopy height model (CHM) in the Ecosystem Structure data product (DP3.30015.001) collected by NEON's Airborne Observation Platform. Vegetation cover data are published alongside the Litterfall data for every year an AOP survey was/is completed at a given site.