Fern Understory as an Ecological Filter at Harvard Forest 1993-1995

This project is was an investigation of the role of the fern understory as an ecological filter that influences the organization of the tree seedling bank in New England deciduous forests. The data files summarize a series of field experiments conducted from 1993 to 1995 evaluating the response of seed germination and seedling growth and survival to experimental understory manipulation. These field studies involved three experimental manipulations of the fern understory: 1) removal of ferns 2) ferns tied back (to remove above-ground shading) 3) ferns left intact (control). These manipulations were established in 180 - 1m2 plots spanning six field sites and 2 different fern species (3 understory manipulations x 2 understory fern species x 6 sites x 5 replicates/site = 180 experimental plots).

本研究旨在探究蕨类下层植被作为生态过滤因子 (ecological filter)，对新英格兰落叶林内树木幼苗库 (tree seedling bank) 群落构建的调控作用。本数据集汇总了1993至1995年间开展的一系列野外实验数据，用于评估种子萌发、幼苗生长与存活对下层植被操控 (understory manipulation) 的响应。本次野外研究包含三种蕨类下层植被操控处理：1）移除蕨类；2）将蕨类植株捆扎固定（以消除地上遮荫效应）；3）保留蕨类原状（对照组）。上述操控处理共设置于6个野外样地内的180块1平方米样方 (plot) 中，涉及2种下层蕨类物种，实验设计为：3种下层植被操控方式 × 2种下层蕨类物种 × 6个野外样地 × 每个样地5次重复 = 总计180个实验样方。