Heterogeneity habitat of three threatened freshwater catfishes

Table 2. Principal component (PC) Loadings from principal component analysis of physical

habitat structure and physiochemical environmental variables from 40 sampling sites

Variables

PC1

PC2

PC3

Water flow (m/sec)

-0.32

-0.04

-0.02

Depth (m)

0.34

-0.01

0.04

Temperature (ºC)

-0.31

-0.32

0.17

Dissolved Oxygen (mg/L)

0.02

0.54

0.31

Conductivity (µS/cm)

-0.05

-0.02

0.54

Turbidity (mg/L )

0.32

0.18

-0.16

pH

-0.15

0.61

-0.23

Total Dissolved Solids (ppm)

-0.29

0.27

-0.20

Fine Substrate (%)

0.01

0.07

0.15

Fine Gravel (%)

-0.08

0.16

-0.10

Coarse Gravel (%)

-0.18

0.05

0.02

*values > 0.25 are in bold.

Table 3. Canonical correspondence analysis summary statistics for the fish and environment

sampled in different rivers. (Tolerance of eigen analysis set at 1E-009)

Fish Assemblage and Habitat Use Pattern

Axis 1

Axis 2

Eigenvalues

0.41

0.17

Species - Environment Correlations

0.90

0.64

Cumulative Percentage Variance

Explained by Species Only

44.83

18.62

Explained by Species + Environmental Variables

44.83

63.46

Interest Correlations with Axis

Water Flow (m/sec)

0.83

-0.07

Depth (m)

-0.72

-0.01

Temperature (ºC)

0.79

0.09

Dissolved Oxygen (mg/L)

0.05

-0.01

Conductivity (µS/cm)

0.23

0.44

International Journal of Bioinformatics and Biological Sciences : v.2 n.3&4. Dec. 2014

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