Deviations from general mean leaf productivity (ΔP) of <i>Thalassia testudinum</i> per station during High growth season (May-September at site 1 and 2, March –August at all other sites) and Low growth season (October-April at sites 1 and 2, September-February at all other sites).

<p>See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600.s006" target="_blank">Table S4</a> for significance differences of ΔP. Only stations with at least 10 sampling events were included. Numbers above the X-axis indicate site number, and the minor ticks indicate the different sampling stations at those sites.</p

Significant long-term trends in seagrass attributes and community parameters at CARICOMP monitoring stations across the nine sites that showed changes consistent with deterioration of the environmental conditions.

<p>The broken smoothed lines connect annual average values and serve to illustrate the inter-annual variability in the data. Data from all samples per year (N = 4-9, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600.s005" target="_blank">Table S3</a>) were used to determine the regression lines (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600.s008" target="_blank">Table S6</a>). D. For Site14, the relationship was determined for the more persistent <i>Syringodium filiforme</i>.</p

Total (above- and below-ground) biomass of the principal components of the community per sampling station grouped per site.

<p>Other grass: species of seagrass other than <i>Thalassia testudinum</i>, mostly <i>Syringodium filiforme</i>. Somatic (decalcified) above-ground weight of the calcareous algae is considered. The boxes and bars represent inter-annual variation, and stations with only one sampling event are excluded. The digits above the bars in the bottom graph indicate N (the number of sampling years). M median of fleshy algae at site 5-station 13. See legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone-0090600-g002" target="_blank">Fig. 2</a> for further explanation.</p

Long-term trends at CARICOMP seagrass stations, including observations on disturbances.

<p>Biomass: total above-ground biomass of the community; Rel abund: relative abundance (biomass) of faster growing seagrass and algal species; Other seagrass: seagrass species other than <i>Thalassia testudinum</i> (mostly <i>Syringodium filiforme</i>); % Above/Total Biomass: percentage of above-ground of total biomass of <i>T. testudinum</i> (<i>S. filiforme</i> for site 14, because <i>T. testudinum</i> was absent in later years at station 33); Productivity: productivity of leaves of <i>T. testudinum</i>. ??? Collapse of seagrass bed, * seagrass beds showed changes that potentially indicate with human-induced environmental deterioration. Trends: <b>I</b> increase, <b>D</b> decrease, n without change, - not determined, <b>^N</b> expected change due to increasing nutrient load, <b>^T</b> expected change due to increasing turbidity, <b>^NT</b> expected change due to either increasing turbidity or nutrient load, changes without symbol were not consistent with expectations of water quality deterioration (See text for further explanation). Conditions at the beginning of monitoring: PRIST (relatively) pristine (undisturbed by humans); INT Moderate disturbance; DIST Disturbed (eutrophication, terrestrial runoff, or overfishing, from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-CARICOMP1" target="_blank">[26]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-CARICOMP2" target="_blank">[29]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-JordnDahlgren1" target="_blank">[47]</a>). See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600.s008" target="_blank">Table S6</a> for information on regression lines. Source: 1. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Murdoch1" target="_blank">[48]</a>, 2. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Fourqurean5" target="_blank">[49]</a>, 3. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Szmant1" target="_blank">[50]</a>, 4. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Fourqurean6" target="_blank">[51]</a>, 5. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-CARICOMP2" target="_blank">[29]</a>, 6. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Carruthers1" target="_blank">[52]</a>, 7. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-RodrguezMartnez1" target="_blank">[33]</a>, 8. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-VanTussenbroek2" target="_blank">[53]</a>, 9. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Davis1" target="_blank">[38]</a>, 10. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Koltes1" target="_blank">[44]</a>, 11. Pers. Obs. K. Koltes, 12.Pers.Obs. H.A Oxenford, 13. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-RodrguezRamrez1" target="_blank">[54]</a>, 14. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-RodriguezRamrez1" target="_blank">[55]</a>, 15. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Fonseca2" target="_blank">[56]</a>, 16. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-Corts1" target="_blank">[57]</a>, 17. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090600#pone.0090600-DCroz1" target="_blank">[58]</a>.</p

Annual leaf productivity of <i>Thalassia testudinum</i> per sampling station.

<p>The stations are grouped per site (underlined, 1–6 stations per site), and stations only sampled during one season are excluded. The boxes and vertical bars represent inter-annual variation. The horizontal lines correspond with the median values, 50% of the cases are within the box limits and the vertical bars indicate the smallest or largest values that are not outliers, • represent values more than 1.5 box lengths from lower/upper box limit, and * represent values more than 3 box-lengths from lower/upper box limit. The digits above the bars indicate N (the number of sampling years). Grey bars represent stations that were not included in the long-term analysis.</p

Map of CARICOMP seagrass sites, ordered according to latitude.

<p>1. Bermuda, 2. USA-Long Key, 3. Bahamas-San Salvador, 4. Cuba-Cayo Coco, 5. Mexico-Puerto Morelos, 6. Mexico-Celestun, 7. Cayman Islands-Grand Cayman, 8. Jamaica-Discovery Bay, 9. Dominican Republic-Parque Nacional Este, 10. Puerto Rico-La Parguera, 11. Belize-Turneffe Island, 12. Belize-Twin Cays/Carrie Bow Cay, 13. Colombia-Isla Providencia, 14. Barbados-St. Lawrence, 15. Colombia-Isla San Andres, 16. Curaçao-Spaanse Water, 17. Colombia-Chengue Bay, 18. Tobago-Bon Accord Lagoon, 19. Venezuela-Isla de Margarita, 20. Venezuela-Morrocoy, 21. Costa Rica-Cahuita, 22. Panama-Isla de Colon.</p