Macrobenthic colonization on artificial seagrass units in a Halodule wrightii meadow — Suape Bay, Brazil

This dataset contains abundance records of benthic macrofauna that colonized Artificial Substrate Units (ASUs) deployed in a monospecific meadow of Halodule wrightii in Suape Bay, Pernambuco, northeastern Brazil. The experiment was carried out during the dry season, with ASUs deployed on 8 December 2016 and the final collection on 6 February 2017, and assessed the combined effect of habitat structural complexity and exposure time on the structure, succession, and functional organization of macrobenthic assemblages. ASUs consisted of 10 cm² plates of synthetic grass (polyethylene filaments) fixed 5 cm above the bottom, at three complexity levels: short grass (SG, 12 mm; 11,392 filaments·m⁻²), medium grass (MG, 30 mm; 67,192 filaments·m⁻²), and tall grass (TG, 50 mm; 10,240 filaments·m⁻²). A balanced design was applied, with three replicates per grass type at each of six exposure times (2, 5, 10, 20, 30, and 60 days), totaling 54 ASU samples. Additionally, on day 30 of the experiment, 9 samples from the natural meadow were collected (3 replicates at each of 3 randomly selected points) and treated as a reference condition. The full set of 63 samples documented 9,439 individuals belonging to 133 taxa across nine phyla (Annelida, Mollusca, Arthropoda, Echinodermata, Cnidaria, Platyhelminthes, Nemertea, Sipuncula, and Chordata), with Crustacea, Mollusca, and Annelida accounting for approximately 97% of total abundance in ASUs. The dataset supports analyses of community structure (PERMANOVA, PERMDISP, CAP, nMDS), alpha diversity profiles via Hill numbers (q⁰, q¹, q²), partitioning of beta diversity into turnover and nestedness components, indicator species analysis (IndVal), and modeling of the relationship between functional traits and assemblage structure (DistLM). Each taxon was classified by feeding habit and substrate position, based on the BIOTIC, WoRMS, and Polytraits databases. Files included: species_abundance_wide.csv — abundance matrix (PRIMER format), rows = taxa, columns = samples species_abundance_long.csv — same data in tidy/long format sample_metadata.csv — metadata for the 63 samples (treatment, exposure time, sampling date, depth, sediment type, etc.) species_metadata.csv — taxonomic list and functional traits for the 133 taxa README.md and data_dictionary.md — full documentation (English and Portuguese versions included) Associated article: Silva, G.F.; Santos, S.N.; Craveiro, N.; Rosa Filho, J.S. Exposure time and habitat complexity shape turnover-driven functional succession in benthic macrofaunal assemblages colonizing artificial seagrass units (under review). The DOI of the article will be added to Related identifiers upon publication. License: CC BY 4.0 — free to share and adapt with attribution.