Physiological responses of scleractinian coral to trace metal enrichment and thermal stress

Coral bleaching events are increasingly frequent due to global climate change and marine pollution. Trace metals, such as manganese (Mn) and iron (Fe), though toxic at high concentrations, are vital for coral physiology, supporting photosynthesis and antioxidation. This study investigates how thermal stress and trace metal exposure interact to influence the physiology of the scleractinian corals Turbinaria irregularis and Montipora mollis. Corals were exposed to Mn and Fe at varying concentrations under control (25°C) and elevated (30°C) temperatures. Mn enhanced photosynthetic efficiency, an increase of 1.7% in M. mollis at 250 nM and 1.4% in T. irregularis at 30°C (p < 0.05). Fe improved photosynthesis by 1.8% in M. mollis at 50 nM and growth rates by 2.1% in T. irregularis at 25°C (p < 0.05). Both metals mitigated bleaching, as seen in reduced relative gray intensity and increased symbiotic algal density, particularly at moderate concentrations. However, elevated temperatures s..., This study aimed to explore the effects of Fe and Mn supplementation on the physiological parameters of two coral species, Turbinaria irregularis and Montipora mollis, under both normal and heat stress treatments. The experimental design, which was based on previous research (Biscéré et al., 2018), incorporated two temperature levels (25°C ± 1°C and 30°C ± 1°C) and two trace metals (Fe2+ and Mn2+) at three concentrations each (50, 100, and 250 nM), as outlined by Reich et al. (2020) and Rodriguez and Ho (2018). A control not exposed to metals was also included. Each treatment was replicated, and the experiment ran for a duration of 14 days. On-site measurements of temperature, salinity, dissolved oxygen (DO), and pH were conducted daily using a handheld multiparameter water quality meter (ProDSS multiparameter digital water quality meter, YSI; Xylem Inc., USA). Digital photographs of coral branches were taken at the experiment’s outset and conclusion for later analysis. Following the ex..., , # Data from: Physiological responses of scleractinian coral to trace metal enrichment and thermal stress

Raw data belonging to:
Ting-Hsuan Tu, Hung-Yen Hsieh, Pei-Jie Meng, and Chung-Chi Chen (2024). Physiological responses of scleractinian coral to trace metal enrichment and thermal stress.

## File Information

### Data_for_Dryad.xlsx

#### Fig. 2_PSII: The photosynthetic efficiency (Fv/Fm) of the scleractinian corals.

**Unit:** All (Fv/Fm) and standard errors are dimensionless

##### Manganese (Mn) treatment

Column: Variables
A: Mn treatment (Control, 50 nM, 100 nM, 250 nM)
B: (Fv/Fm) of *Montipora mollis* at 25°C
C: Standard error for (Fv/Fm)_Mn_M_25  
D: (Fv/Fm) of *Montipora mollis* at 30°C  
E: Standard error for (Fv/Fm)_Mn_M_30
F: (Fv/Fm) of *Turbinaria irregularis* at 25°C
G: Standard error for (Fv/Fm)_Mn_T_25    
H: (Fv/Fm) of *Turbinaria irregularis* at 30°C
I: Standard error for (Fv/Fm)_Mn_T_30

##### Iron (Fe) Treatment

J: Fe treatment (Control, 50 nM, 100 nM, 250 nM)...,