3.2.5 A summary of chemical data
Overall, in terms of chemistry, soils in Anak Krakatau and also profiles
Panjang1, Rakata1, and Sebesi1, which all were located at a higher
elevation, showed the least development. Soils at the coast of Rakata
and Sebesi showed a reasonable development in terms of higher pH, CEC,
and OC content. In contrast, soils in Sebesi were most developed with
higher values of pH, CEC, OC, and Alo,
Sio, and Feo.
In summary, we performed a linear discriminant analysis on the soil
chemical properties as a function of the four islands. We combined data
on each isle at all depths as a group as the profile data represents the
typical soil materials in the area. In addition, there was minimal soil
development, and soil depth variation can only be seen in a few
properties (e.g., O C, CEC). Figure 9 shows the biplot of the first two
canonical axes of the discriminant analysis. It confirms that soils of
Rakata and Panjang displayed similar properties, but they were distinct
from the soils of Sebesi and Anak Krakatau. Soils of Sebesi had chemical
characteristics (higher CEC, Sio, Alo,
Feo), indicating a more developed stage than soils of
the other islands. Soils in Anak Krakatau were least developed (Figure
9).