CRAMP Rapid Assessment. Sediment Analysis
The gravel fraction is removed prior to analyses to reduce overweighting proportions of other size fractions by large material. To avoid multicollinearity, one size fraction (very fine sand) was removed from the analysis. Additionally, partial F-tests determined that this grain-size to contribute the least in explaining sediment variability among sites.
Bulk sediments were collected from 94 of the 152 stations at 52 sites. At stations where sediments were not collected, sediment data from stations at the same site with similar biota and environmental conditions were substituted (>90%) using a similarity matrix. Stations not meeting substitution criteria were omitted from the analyses (15).
Five sediment parameters were used in analyses:
Principal components analysis (PCA) is used to define the position of stations in relation to the sediment variables.
Last Update: 04/21/2008
By: Lea Hollingsworth
Hawai‘i Coral Reef Assessment & Monitoring Program
Hawai‘i Institute of Marine Biology
P.O. Box 1346
Kāne‘ohe, HI 96744