Geophysical Expression for Groundwater Quality in Part of Chittoor District, Andhra Pradesh, India - Management of Natural Resources in a Changing Environment - page 55

There is significant qualitative correlation between S and total hardness (TH). In
the contour map shown in Fig. 4b in the eastern region the contours of high longitu-
dinal unit conductance match well with contours of higher values of total hardness.
Similarly in the western region low values of contours of S match significantly with
low values of contours of total hardness. Figure 4b shows the correlation of S vs
TH. There is a remarkable direct relation between S and TH. The correlation coef-
icient r 2 is 0.4025 which amounts to 64 %. Hence one of the parameters can be
quantitatively estimated if either is known.
In the contour maps shown in Fig. 5a , there is total correlation between contour
pattern of S and Na. Contours showing higher values of Na match remarkably with
contours showing higher values of S significantly in space. Similarly, contours
showing lower values of Na in space match well with lower values of contours of S .
In the contour maps shown in Fig. 5a , white tone represents higher values and darker
tone represents lower values of parameters namely S and Ca. It is clearly observed
that high level contours of S match with high level contours of calcium and vice-
versa. Hence there is direct qualitative relationship between S and Ca.
Figure 5b shows a direct correlation of S vs Na. The correlation coefficient r 2 is
0.3236, which amounts to 56 %. Figure 5c shows correlation between S and Ca. The
correlation coefficient r 2 which is 0.3709 and amounts to 61 % shows a significant
quantitative relationship between S and calcium. Hence one of the parameters can
be quantitatively estimated if either is known.
In Fig. 6a the contours of specific conductance and longitudinal unit conductance
are shown. The contours in the white tone are higher values, and the contours in
grey and black tones are lower values of the parameters. There is total match of
white grey and dark areas in the map of S with white grey and dark areas observed
in the map of specific conductance. Hence, there is a significant qualitative relation-
ship between S and specific conductance. Specific conductance increases with
increase in the values of S and vice-versa. Figure 6b shows the correlation of S and
specific conductance, the correlation shows a direct relation between S and specific
significant. Hence one of the parameters can be quantitatively estimated if either is
known. In Fig. 6a in the contour map, white tone indicates higher values, and the
contours in grey and black tones indicate lower values. There is significant qualita-
tive relationship between S and sodium adsorption ratio, because the grey and white
tone regions match significantly with each other. Figure 6c shows correlation of S and
sodium adsorption ratio, a direct relationship is observed between these parameters.
The correlation coefficient r 2 is 0.4662 which amounts to 68 % which is significant.
Hence, one of the parameters can be quantitatively estimated if either is known.
In Fig. 7a the contour map shows that except a minor discrepancy, the correlation
in the north central parts of the study areas, a complete match between the patterns
of contours S and Cl can be observed. Figure 7b shows that the quantitative relation
of S and Cl is almost direct. The correlation coefficient r 2 is 0.4688 which amounts
to 68 %. Hence, one of the parameters can be quantitatively estimated if either is
known. In Fig. 7a the nitrate contour map indicates the correlation in the north cen-
tral parts of the study area, there is complete match between S and nitrate. In Fig. 7c