Plant phenology and performance in the ITEX plots at Barrow and Atqasuk, Alaska

• Main Author: Robert Hollister
• Format: Dataset
• Language: unknown
• Published: Arctic Data Center 2016
• Subjects: Barrow; Carex aquatilis; Alaska
• Online Access: https://doi.org/10.18739/A26Q21

These files contain data representing the periodic plant measures of all species within each plot in a CSV format. The data presented are phenological development (date of leaf bud burst, inflorescence emergence, flower bud, flower opening, flower withering, seed development, seed dispersal, and senescence), seasonal growth (length of leaf, and length of inflorescence), seasonal flowering (number of inflorescences in flower within a plot), occurrence of events (yes or no for leaf, inflorescence, bud, flower, and seed), and annual growth and reproductive effort (number of leaves, diameter of rosette, number of branches, maximum leaf length, number of inflorescences, maximum inflorescence length, number of buds, number of flowers, and number of seeds) collected weekly or yearly for all plant species during the summers of 1994-2014 for 48 plots (24 experiment open-top chamber plots and 24 control plots) at four sites (Atqasuk Wet Meadow, Atqasuk Dry Heath, Barrow Wet Meadow, and Barrow Dry Heath). Plant development was followed throughout the entire summer. Plant measures were determined based on species morphology and ease of information collection. Within each plot three permanently marked individuals were monitored for each species if possible. Due to the low percentage of flowering, data on reproductive traits required the measurement of non-tagged plants. Four different data types were collected. They were: 1) 1-3 permanently marked individual plants of each species within a plot; 2) total plot measures of a species, such as the number of flowers per plot or the first occurrence of a phenophase; 3) the 1-3 largest reproductive individual plants of a species within a plot; and 4) the 1-3 largest vegetative individual plants of a species within a plot. For species such as graminoids that do not form distinct individuals unit areas were established to monitor change over years. The size of unit areas of Carex aquatilis subspecies stans in the Barrow Wet Meadow site and all the species in the Atqasuk Wet Meadow site was 10 by 10 cm. All other unit areas were 5 by 5 cm in size.