Hubbard Brook Experimental Forest Valleywide Plots: GIS Shapefile

This coverage was developed as part of Paul Schwarz's dissertation research. Fifteen North-South transects were established at 500m intervals to span the entire Hubbard Brook Valley. Between 1995 and 1997, 371 plots were positioned at 100m and 200m intervals along each transect. In 1998, 60 additional plots were positioned: three plots were placed at 25m intervals between two existing plots at 20 locations that were stratified according to elevation and aspect and selected at random. Hence, a system of 431 permanent 500 square meter circular plots were established. No plots were located in the six experimental watersheds designated for ecosystem research. The sampling layout of the plots was chosen to facilitate the analysis of spatial patterns in the forest vegetation by utilizing a wide range of distance intervals between plots. These intervals ranged from approximately 25m to several thousand meters. Data distributed as shapefile in Coordinate system EPSG:26919 - NAD83 / UTM zone 19N.

本空间覆盖数据集是保罗·施瓦茨（Paul Schwarz）学位论文研究的一部分成果。研究团队沿500米间隔布设15条南北向样带，以覆盖整个哈伯布鲁克山谷（Hubbard Brook Valley）。1995年至1997年间，沿每条样带以100米和200米的间隔布设了371个样地。1998年，新增布设60个样地：在20个按海拔和坡向分层并随机选取的点位中，每处现有两个样地之间以25米间隔增设3个样地。由此，共计建立431个永久性圆形样地，单个样地面积为500平方米。所有样地均未布设于6个用于生态系统研究的实验集水区内。本次样地采样布局的设计初衷，是通过设置跨度覆盖约25米至数千米的多样间距，便于开展森林植被空间格局分析。数据集以形状文件（shapefile）格式分发，采用的坐标系为EPSG:26919 - NAD83 / UTM zone 19N。