Global Tundra Vegetation Change - 30 years of plant abundance data from unmanipulated and experimentally-warmed plots

We amassed plot-based data on vegetation abundance (cover, point-frame hits, biomass, subplot frequency, stem-counts) from permanently marked plots, transects, and study areas throughout the tundra biome, and in and out of warming experiments. Criteria for inclusion in the warming treatment analysis were measures of plant abundance in warmed and control plots in at least one year. For the long-term change project, criteria for inclusion were repeat-measurements of plant abundance in unmanipulated vegetation using the same techniques in 2+ study years at least 5 years apart in time. We also collected air and soil temperature data (where available) from the study site locations.

本研究收集并整合了覆盖整个苔原生物群区（tundra biome）的永久标记样地、样带及研究区域，以及增温实验（warming experiments）内外的样地尺度植被丰度数据，测定指标涵盖植被盖度（cover）、点框架法击中点数（point-frame hits）、生物量（biomass）、小样方频度（subplot frequency）与茎秆计数（stem-counts）。增温处理分析的纳入标准为：至少在1个研究年度内获取了增温样地与对照样地的植物丰度测定数据。针对长期变化研究项目，纳入标准为：在至少间隔5年以上的2个及以上研究年度中，采用相同技术手段对未受人为干扰的植被开展植物丰度的重复测定。本研究同时收集了各研究点位的空气与土壤温度数据（若可获取）。