Biomass removal at the initiation of a biodiversity experiment at the Jornada Basin LTER site in 1995

This dataset contains data on vegetation biomass removed from treatment plots during the establishment of a biodiversity experiment at the Jornada Basin LTER site in southern New Mexico, USA. In fall of 1995, various combinations of plant functional groups or species were experimentally removed from 25 x 25 meter plots with the objective to distinguish the differential effects of plant community biomass, functional groups, and biodiversity within functional groups on ecosystem and plant community function. Eight different treatments were established with selective removal of species or functional groups: control (C, no removals); four functional group removal treatments (PG, perennial grass removed; S, shrubs removed; SSh, subshrubs removed; Succ, succulents removed), and three species richness manipulation treatments. Richness manipulations included a simplified treatment (Simp), where only the single most abundant species of each growth form is preserved and all other species in the growth form are removed, a reduced‐Larrea treatment (rL), where the Larrea is assumed to be the dominant and is removed while minority components remain, and a reduced-Prosopsis treatment (rP), where Prosopis rather than Larrea is removed as the shrub dominant. The amount of plant material removed during the establishment of these treatments was recorded for later use as covariate or measure of disturbance. Removed fresh material was weighed in the field by species, then converted to dry mass using a subset of removed plot vegetation that was oven-dried and weighed in the lab. Variables in this file summarize the dry mass of plants removed by growth form (functional group, i.e. shrub, subshrub, perennial grass, succulent), and by total live dry mass, for each plot in the biodiversity experiment. Also provided are masses of dead material collected from plots (same groups as live material removed for each treatment) and total dry mass, live plus dead. Species-level data are available upon request. This study is complete.

本数据集收录了美国新墨西哥州南部乔纳达盆地长期生态研究（LTER, Long-Term Ecological Research）站点开展生物多样性实验期间，各处理样地内被移除的植被生物量相关数据。1995年秋季，研究人员在25米×25米的样地中通过实验手段移除不同组合的植物功能群或物种，旨在解析植物群落生物量、功能群以及功能群内生物多样性对生态系统与植物群落功能的差异化影响。本次实验共设置8种选择性移除处理：1个对照组（C，无移除操作）；4个功能群移除处理组（PG：移除多年生草本；S：移除灌木；SSh：移除半灌木；Succ：移除肉质植物）；以及3个物种丰富度操控处理组。丰富度操控处理包含以下三类：简化处理（Simp），即仅保留每种生长型中丰度最高的单一物种，移除该生长型内其余所有物种；弱化拉瑞阿属处理（rL），该处理假定拉瑞阿属为样地优势物种并将其移除，保留其余伴生组分；弱化牧豆树属处理（rP），该处理以牧豆树属替代拉瑞阿属作为灌木优势种并将其移除。研究人员记录了上述处理设置过程中移除的植物材料总量，后续可将其作为协变量或干扰程度的量化指标。移除的新鲜植物材料按物种在野外进行称重，随后通过采集部分移除样地的植被样本开展室内烘箱干燥称重，将鲜重换算为干重。本数据文件中的变量汇总了该生物多样性实验各处理样地中，按生长型（即功能群：灌木、半灌木、多年生草本、肉质植物）以及总活生物量干重统计的被移除植物干重数据。同时文件还提供了从样地中收集的枯落物生物量数据（分类方式与各处理组移除的活体植物材料一致），以及活体与枯落物总干重数据。物种水平的原始数据可通过申请获取。本研究已全部完成。