DOI: 10.5061/dryad.pzgmsbd0d
title: Assessing the effectiveness of global protected areas in conserving plant community completeness

description: The establishment of terrestrial protected areas (PAs) is an effective
 strategy for conserving plant species diversity across multiple spatial
 scales—from local to global. This effectiveness can be assessed using the
 concept of plant community completeness, which quantifies the degree to
 which the local biodiversity potential (i.e., the site-specific species
 pool) is realized. Although community completeness offers valuable
 insights for nature conservation, few studies have applied this metric to
 evaluate PAs. We present the first global assessment of plant community
 completeness for PAs. We analyzed 41,980 plots located inside PAs and
 28,599 plots outside PAs, comparing species richness, species pool, and
 community completeness across various ecoregions and biomes. Using the
 Getis-Ord Gi* statistic, we identified areas of high community
 completeness and evaluated the effectiveness of PAs in conserving this
 metric. Furthermore, we determined ecoregions with the potential to
 increase community completeness by the expansion of conservation areas
 outside PAs. Significant variations in species richness, species pool, and
 community completeness were observed both inside and outside PAs across
 biomes. At the global scale, the threshold for high community completeness
 was estimated at 0.208. The lowest 10% quantile values of high community
 completeness were approximately 0.1 for different biomes in the PA
 assessment. Biome-specific thresholds revealed that PAs effectively
 conserve community completeness in 57.2% of the study ecoregions but
 exhibit limited effectiveness in maintaining community completeness in 71
 ecoregions. Community completeness outside PAs showed considerable
 potential for further enhancement. Given the nearly fixed nature of the
 species pool and its relationship with community completeness, the high
 completeness observed outside PAs underscores the need to expand
 conservation areas in 40.7% of the study ecoregions, spanning tropical,
 temperate, and desert biomes. Additionally, 105 ecoregions show potential
 for improving community completeness through restoration efforts outside
 existing PAs. Synthesis and applications: Community completeness is a
 powerful tool for evaluating the effectiveness of PAs in conserving plant
 diversity. It is critical to test whether PAs are in high completeness
 areas, i.e., in appropriate sites, and suggest which areas are in theory
 better suited for restoration and transformation into PAs.
description: # Assessing the effectiveness of global protected areas in conserving
 plant community completeness Dataset DOI:
 [10.5061/dryad.pzgmsbd0d](10.5061/dryad.pzgmsbd0d) ## Description of the
 data and file structure ### File and variables #### File: DATA-updated.csv
 **Description:**  ##### Variables * Plot code: The code of study plots. *
 Source: The database source. * Observed diversity: The ln-transformed
 species richness per plot. * Species pool: The ln-transformed species pool
 per plot. * Community completeness: The percentage of species richness for
 the species pool per plot. * Status: The status of protected or
 non-protected areas for the study plots. * Ecoregion: The ecoregion to
 which the sampling plot belongs. * Biome: The biome to which the sampling
 plot belongs.