DOI: 10.5061/dryad.kprr4xhh1
title: Global patterns and drivers of seagrass biomass, net primary production and meadow structure

description: We decipher global patterns in seagrass growth and structure to advance
 seagrass science, facilitate multidisciplinary research, and promote
 effective management strategies and policy development for seagrass
 habitats. A global data set on seagrass total biomass, total NPP, shoot
 density, and percent cover was compiled for 11 genera. Here, we tested how
 these variables change across seagrass genera, life-history strategy, and
 geographic location, and then sought to decipher the environmental drivers
 of the patterns observed. The mean (±SE) total biomass of seagrasses
 globally was estimated at 340 ± 10 g DW m
 -2, and total NPP was estimated at 5.4 ± 0.4 g DW m -2
 d-1. Mean shoot density across all genera was 1,780 ± 67 shoots m-2, and
 percent cover was 42 ± 1%. Persistent genera showed the highest total
 biomass, followed by opportunistic and then colonising genera, whereas
 shoot density was higher for colonising than for persistent, which had the
 highest percent cover. Latitudinal and bioregional patterns were
 identified for some genera, and were mostly driven by genus-specific
 traits, followed by localised environmental factors. Trends in seagrass
 meadow ecology were largely influenced by seagrass genera and their
 life-history strategy, with localised environmental factors, such as
 temperature and nutrients, also playing a role. Global estimates of
 seagrass biomass and NPP were 2 times higher than previously reported.
 Seagrass life-history strategies modulate the trade-offs between NPP and
 biomass to thrive in specific habitats. This study provides the most
 updated global synthesis of patterns in seagrass growth and structure.
description: # Global patterns and drivers of seagrass biomass, net primary production
 and meadow structure Dataset DOI:
 [10.5061/dryad.kprr4xhh1](10.5061/dryad.kprr4xhh1) ## Description of the
 data and file structure Data file of metadata and seagrass variables
 extracted from studies looking at seagrass productivity and structure from
 1975-2024 and environmental variable data from Bio-ORACLE v2.0
 (2000-2014).\ Empty cells denoted that data was not available. R script
 for processing analysis and graphing  ### Files and variables #### File:
 Final_code_analysis_and_plotting.R **Description:** Code for analysing and
 plotting data. This R script imports and cleans a seagrass dataset, adds
 biological and geographic classifications,customize the appearance of the
 ggplot map and counts the number of non-missing observations of total
 productivity per genus. #### File: Dataset_ecological_biomass_complete.csv
 **Description:**  Seagrass ecology variable data collected from
 meta-analyses including informati,on on location and BIO-oracle
 environmental data. ##### Variables * Unique.ID: For identifying entries
 from different papers * Latitude: Latitude * Longitude: Longitude *
 Bioregion: Based on Short et al., 2007 that formulat ( bioregions to
 classify seagrass distribution.  * Geotype: Whether the seagrass was
 Estuarine or marine * Genera: The genus of seagrass  * Year.of.sampling:
 When the record was collected * Above.ground.biomass..g.DW.m.2.: Above
 ground biomass in grams of dry weight per metre squared *
 Below.ground.biomass..g.DW.m.2.: Below ground biomass in grams of dry
 weight per metre squared * Total.biomass..g.DW.m.2.: The sum of Above
 ground and below ground biomass if total biomass was not reported *
 Shoot.density..no..shoots.m.2.: Shoot density in the number of shoots per
 metre squared * Percent.cover....: Percentage cover of seagrass shoots *
 Leaf.density..no..leaves.m.2.: Leaf density in the number of leaves per
 metre squared * Above.ground.production..g.DW.m.2.day..1.: Above ground
 production in grams of dry weight per metre squared per day *
 Below.ground.production..g.DW.m.2.day..1.: Below ground production in
 grams of dry weight per metre squared per day *
 Total.production..g.DW.m.2.day..1.: The sum of above ground and below
 ground production if not reported  * Shoot.production..g.DW.m.2.day..1.:
 Growth of shoots in grams of dry weight per metre squared per day *
 Leaf.production..g.DW.m.2.day..1.: Growth of leaves in grams of dry weight
 per metre squared per day * Reference: Article reference * DOI: Link to
 article * BO22_tempmean_ss: Mean sea surface temperature ºC *
 BO22_tempmax_ss: Maximum sea surface temperature ºC * BO22_tempmin_ss:
 Minimum sea surface temperature ºC * BO22_ph: ph * BO22_parmax: Maximum
 photosynthetically available radiation E.m ^-2^.day ^-1^ * BO22_parmean:
 Mean photosynthetically available radiation E.m^-2^.day^-1^ *
 BO22_carbonphytomax_ss: Maximum sea surface phytoplankton mmol.m^-3^ *
 BO22_carbonphytomean_ss: Mean sea surface phytoplankton mmol.m^-3^ *
 BO22_ironmean_ss: Mean sea surface iron concentration mmol . m^-3^ *
 BO22_nitratemax_ss: Maximum sea surface nitrate concentration mmol . m^-3^
 * BO22_phosphatemax_ss: Maximum sea surface phosphate concentration
 mmol.m^-3^ * BO22_ppmax_ss: Maximum sea surface primary productivity mmol
 . m^-3^ * BO22_curvelmean_ss: Mean sea surface water velocity m.s^-1^ *
 BO22_ppmean_ss: Mean sea surface primary productivity mmol . m^-3^ *
 BO22_salinitymean_ss: Mean salinity * BO22_silicatemean_ss: Mean silicate
 concentration mmol.m^-3^ * BO22_dissoxmin_ss: Sea surface minimum
 dissolved molecular oxygen mmol . m^-3^ * BO22_dissoxmean_ss: Sea surface
 mean dissolved molecular oxygen mmol . m^-3^ * BO22_chlomean_ss: Sea
 surface mean chlorophyll  mg . m^-3^