Gladstone Fish Health Investigation 2011 - 2012 - Western Basin ...

Department of Science, Information Technology, Innovation and the ArtsThe principal components overall spatial representation for the 13 metals (Table 2.2) is shown inFigure 2.1.43Bundy2Dimension 2 (23% variation)210-1Narrows2Port2Bundy1Fitzroy2Fitzroy1-2Narrows1Port1-4 -3 -2 -1 0 1 2 3Dimension 1 (32% variation)Figure 2.1. Movements of the overall location and trip principal component means inmultidimensional space. The Gladstone sites are indicated by the circles with the solid lines, and thereference sites by the squares with the dotted lines.Summarising by regionsThe means for the individual locations can be combined into ‘Gladstone’ (Port area and theNarrows) vs. ‘Reference’ (Bundaberg and Fitzroy River), as listed in Table 2.4. The pooledstandard error for each mean was calculated according to the usual sum-of-variances method (Raj1968), and these were used to conduct a t-test for the degree of difference between these regionalmeans. In each of the trips, three of the six significant differences showed a higher level for thereference sites.Page 38