Years since implementation of U.S. Forest Service Activity Tracking System (FACTS) vegetation management activities for bat habitat

This data release contains the spatial raster outputs, R code, and lookup table from a synthesis of U.S. Forest Service Activity Tracking System (FACTS) vegetation management activities hypothesized to influence bat habitat. The included raster data cover the continental United States and represent the number of years that have passed since a given management action was implemented, assessed with a pixel resolution of 250 m. Each raster represents a unique time slice and vegetation management type. The FACTS database includes information on planned and completed management activities related to fire, fuels, silviculture, and invasive species, among others. We consulted with U.S. Forest Service silviculturists to identify 78 different management actions that we hypothesized could influence summer bat occupancy. We grouped these management actions into four vegetation management types: clear-cutting, fire, thinning, and ground vegetation management. We assumed that each of the different management actions in a type likely resulted in similar landscape modifications. For example, the “ground vegetation management” type was composed of 18 different management actions, including “Compacting/Crushing of Fuels” and “Site Preparation for Planting - Mechanical” (FACTS_CODES.csv), which we assumed resulted in similar outcomes for bats across the landscape.

本数据集发布内容包含：经综合分析得到的美国林务局活动跟踪系统（U.S. Forest Service Activity Tracking System, FACTS）植被管理活动的空间栅格输出、R代码与查找表，上述活动被推测会对蝙蝠栖息地产生影响。本次包含的栅格数据覆盖美国本土，以250米的像素分辨率表征某一管理措施实施以来的时长。每张栅格对应唯一的时间切片与植被管理类型。FACTS数据库涵盖与火灾、燃料管理、营林活动及外来物种防控等相关的规划与已完成管理活动信息。我们联合美国林务局营林专家，筛选出78项推测会影响蝙蝠夏季栖息的管理措施，并将其划分为4类植被管理类型：皆伐、火烧、抚育间伐以及地表植被管理。我们假设同一类别下的各项管理措施，对景观造成的改造效果大致相似。例如，“地表植被管理”类别包含18项具体措施，包括“燃料压实/粉碎”与“机械造林整地”（FACTS_CODES.csv），我们认为这些措施在全国范围内对蝙蝠产生的影响效果相近。