Bonanza Creek LTER Photo Monitoring

This data file represents a photo monitoring project in large reference stands at Bonanza Creek Long Term Ecological Research Site (BNZ LTER) 26 km southwest of the University of Alaska Fairbanks campus, Fairbanks, Alaska. The photo monitoring took place in six mapped and measured reference stands representing white spruce, Alaska birch, and aspen-dominated stands, with one stand in the mature or old growth condition and a comparable site that was the same forest type until a high-severity, stand-replacing crown fire in 1983, for a total of 6 initial stands. The 1983 Rosie Creek Fire was a human-caused wildfire that burned 8,600 acres including about 1/3 of the Bonanza Creek Experimental Forest. The old growth white spruce reference stand was expanded by 1.0 ha to two contiguous hectares, and the burned aspen stand by 0.25 ha to one full hectare (initial) plus an adjacent quarter-hectare. Since 1993 the second old-growth white spruce hectare and second burned aspen quarter-hectare received the full photo-monitoring protocol as the original 6 reference hectares, making a total of 8 photo stand locations.本数据集对应阿拉斯加州费尔班克斯市阿拉斯加费尔班克斯大学校园西南26公里处的博南扎溪长期生态研究站（Bonanza Creek Long Term Ecological Research Site，BNZ LTER）的大型参照样地摄影监测项目。本次摄影监测覆盖6个经测绘与实地测量的参照样地，涵盖白云杉（white spruce）、阿拉斯加桦木（Alaska birch）以及以颤杨（aspen）为主的林分类型，其中1个样地为成熟老龄林分，另有1个同森林类型的对照样地——该样地在1983年遭遇高烈度、全林冠烧毁的火灾，初始监测样地共计6个。1983年的罗西河野火（Rosie Creek Fire）为人为引发的山火，过火面积达8600英亩，波及博南扎溪实验林约三分之一的区域。原始林白云杉参照样地的面积由1.0公顷扩建至相邻的2公顷；受火烧的颤杨参照样地则从初始的1公顷扩建为1公顷本体加上相邻的0.25公顷区域。自1993年起，新增的第二块原始林白云杉样地（1公顷）与第二块受火烧的颤杨样地（0.25公顷）均按照初始6个参照样地的完整摄影监测规程开展监测，最终摄影监测样地总数增至8处。