Plant density measurements in International Tundra Experiment (ITEX) and Arctic System Science Program (ARCSS) plots at Utqiaġvik and Atqasuk, Alaska

Arctic ecosystems are changing in response to arctic warming, which is proceeding more than twice as fast as the global average. The International Tundra Experiment (ITEX) was established in the early 1990s to understand the effects of warming and environmental variability on tundra vegetation properties and ecosystem function. The ITEX program has been extremely valuable for detection of changes in tundra plant and ecosystem responses to experimental warming and to background climate change across sites that span the major ecosystems of the Arctic. These files contain data representing the plant cover and counts of individuals in 5, 10” by 10” square subplots at Utqiaġvik (formerly Barrow) and Atqasuk in a text comma delimited format. The 5 subplots were established in existing plots. These include 96 ITEX plots and a subset of 30 ARCSS grid plots in Utqiaġvik and 96 ITEX plots and a subset of 30 ARCSS grid plots in Atqasuk. The data presented were collected from 2011-2019 at both Utqiaġvik and Atqasuk, and during 2021 at Utqiaġvik only.北极生态系统正响应北极变暖而发生改变，而北极变暖的速率是全球平均水平的两倍以上。国际冻原实验计划（International Tundra Experiment, ITEX）于20世纪90年代初启动，旨在阐明增温与环境变异性对冻原（tundra）植被特征及生态系统功能的影响。ITEX计划在覆盖北极各大主要生态系统的各类样点中，为检测冻原植物与生态系统对实验增温及背景气候变化的响应变化提供了极为重要的支撑。 本数据集包含以逗号分隔的文本格式数据，记录了乌特恰维克（Utqiaġvik，旧称巴罗）与阿塔萨克两地的5个10英寸×10英寸方形小样方内的植物盖度与个体数量。 该5个小样方均设置于已有的样地中，其中乌特恰维克地区包含96个ITEX样地与30个ARCSS网格样地子集，阿塔萨克地区同样包含96个ITEX样地与30个ARCSS网格样地子集。 本次发布的数据于2011年至2019年在两地同步采集，并于2021年仅在乌特恰维克地区补充采集。