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Table 6 Coral response thresholds (NOAEL/LOAEL) of all studies concerning the effects of suspended sediment on corals

From: Effects of sediment exposure on corals: a systematic review of experimental studies

Coral age class Binary coral response # Treatment groups* (controls included/excluded) # Studies/articles with binary data # Species/genera with binary data NOAEL threshold LOAEL threshold
Concentration (mg/L) Duration Concentration (mg/L) Duration
Gametes Reduced fertilization success? 110/86 10/6 4/2 25.0 30.4
Larvae Larval mortality? 63/52 7/4 5/2 29.5 30.0
Limited settlement? 30/20 7/4 4/3 34.6 57.8
Juveniles Physiological limitation? 20/15 2/1 3/2 10.0 0 10.0 1 h
Recruit mortality? 16/9 2/2 4/3 100.0 40 days 100.0 40 days
Adults Reduced P/R ratio? 49/34 3/3 4/4 35.8 2 h 35.8 2 h
Reduced photosynthetic efficiency? 238/180 6/5 8/6 35.8 56 days 35.8 56 days
Local bleaching? 92/54 8/7 10/6 3.2 1 day 3.2 1 day
Reduced growth rate? 79/47 7/5 12/12 49.0 31 days 58.6 31 days
Small tissue necroses? 210/147 4/4 8/6 3.2 14 days 3.2 14 days
Large tissue necroses? 210/147 4/4 8/6 29.1 84 days 29.1 84 days
Total colony mortality? 272/176 8/6 17/14 29.1 40 days 29.1 40 days
Adults ANY MORTALITY?* 272/176 8/6 17/14 3.2 14 days 3.2 14 days
ANY ADVERSE EFFECT?* 360/244 14/11 21/16 3.2 2 h 3.2 2 h
All ANY MORTALITY?* 376/261 19/11 21/15 3.2 12 h 3.2 12 h
ANY ADVERSE EFFECT?* 585/423 37/20 26/18 3.2 0 3.2 1 h
  1. *A ‘treatment group’ is an experimental unit of corals exposed to the same exposure conditions within a study—these may be control (no sediment exposure) or treatment conditions of differing exposure concentrations and/or durations. ‘Physiological limitation?’ for juvenile corals indicates either reduced P/R ratio, reduced photosynthetic efficiency, or reduced growth rate. These are combined here because they represent the physiological results from only one article. = Double dashes ‘–' indicate that data were irrelevant. Any adverse effect is defined as any response of a coral individual, colony, or treatment group that may negatively affect a coral’s fitness and/or survival. These adverse effects may include physiological changes (e.g., reduced growth or photosynthetic rates), bleaching, tissue necrosis, and colony mortality. Any mortality is inclusive of death of tissue (small and large necroses) or of the entire coral colony, and thus excludes sublethal coral responses