Table 1.
Mean (±SD) water quality parameters (mg L−1) for sites on the north coast of Tobago: total suspended solids [44], phosphate, nitrate, ammonia and nitrite.
Figure 1.
Location of study sites: A. map of the southern Caribbean and B. the location of settlement plates at five reef sites on Tobago’s northern coast and the control site, Sisters Rocks.
Figure 2.
Mean (±95% CI) sedimentation rates for: A. total sedimentation; B. clastic sediment; C. carbonate sediment.
Lowercase letters above bars indicate significantly different sites (p<0.05, one-way ANOVA with Tukey HSD, n = 6, *p<0.01, **p<0.001). Lower case letters conform to the first letter in the name of each site.
Table 2.
Site descriptions characterising the reef framework where experimental tiles were deployed.
Figure 3.
Box whisker plots detailing calcareous encruster cover on: A. all substrates; B. cryptic substrates; C. exposed substrates; and D. vertical substrates.
Data presented for calcareous encruster groups: total calcareous cover (Tot); crustose coralline algae (CCA); cheilostome bryozoans (Ch); barnacles (Bar); foraminifera (For); serpulids (Ser); coral recruits (Rec); bivalves (Biv), other calcareous organisms (Oth).
Figure 4.
MDS ordinations of the matrices constructed from A. the benthic cover (%) of calcareous encrusters, and B. calcification rates (g m−2 y−1) for: CCA, cheilostomes, barnacles and all ‘other’ encrusters.
Plots are coded for micro-habitat (exposed, cryptic, vertical) and sites identified by letter.
Figure 5.
Box whisker plots detailing calcification rates (CaCO3 g m−2 y−1) by crustose coralline algae (CCA), cheilostome bryozoans (Ch), and barnacles (Barn) on: A. all substrates; B. cryptic substrates; C. exposed substrates; and D. vertical substrates.
Figure 6.
Box whisker plots detailing calcification rates (CaCO3 g m−2 y−1) by encrusters in different orientations (cryptic, exposed and vertical settlement plates).
Table 3.
Encruster calcification rates (g m−2 y−1) for settlement plate orientations: total (all orientations combined, n = 90), exposed (n = 30), cryptic (n = 30) and vertical (n = 30) substrates.
Figure 7.
Relationships between sediment and encrusters.
Correlations between total sedimentation rates and A. total calcification, B. coralline algae calcification, C. cheilostome calcification, and D. foram cover (%), E. barnacle calcification, and F. serpulid cover (%). Raw data are shown as circles, linear regression lines have been fitted.
Table 4.
Relationship between sedimentation (total, clastic and carbonate) and encrusting foram cover and serpulids encruster cover (%).
Table 5.
Relationships between sedimentation (total, clastic and carbonate) and calcification (g m-2 y-1) by major taxa on different tile orientations.