Taxonomic and functional diversity covary in rock pool microalgal communities despite their different drivers - Environmental and diatom data

We sampled 30 brackish‐watered, isolated rock pools once a month (17 May, 22 June, and 22 July) in 2016 on a granitic outcrop in the western island of Pihlajasaari (66°68′449″N, 38°40′48″E), ca. 2 km south of Helsinki, Finland on the coast of the northern Baltic Sea. We examined the drivers and covariance of taxonomic and functional diversity among the rock pool communities. We measured water pH, conductivity, and temperature in the field, and pool morphometrics (i.e., max depth, length, and width) to the nearest centimeter, and calculated pool area (length * width). We collected a 0.5 L water sample from each pool for the determination of total P (SFS‐EN ISO 2004). We estimated pool X and Y coordinates (based on the perpendicular pool distance from the shore and the horizontal pool distance from the map origin in the southern end parallel to the shoreline, respectively) and mean isolation as a mean Euclidean distance (i.e., the sum of distances to five closest pools divided by five; Va...