Geography Reference
In-Depth Information
Latitude & Longitude of Sampling Sites
Geographical Location of Sampling Sites
Water Quality
Data
Preparing Attribute Database
Point Map of Each Attribute
Estimating Experimental Variogram
Fitting Geostatistical Models
Geostatistics
Selection of Best-Fit Geostatistical Model
GIS-based Spatial Interpolation
Spatial Distribution Map of Water Quality Data
Figure 3. Flowchart showing step-by-step methodology for applying GIS and
geostatistical techniques for generating maps of water quality data.
The values of separation vectors, e.g., h
1
, h
2
etc. are decided first such that
h
x
x
(8)
i
j
Depending upon the value of h, the data are grouped into pairs and some
i
) (Goovaerts,
function as defined below is averaged to obtain a variogram (
1997):
N
1
h
2
(
h
)
z
(
x
)
z
(
x
h
)
i
i
2
N
(9)
h
i
1
where, N
h
= number of pairs for a given lag distance h.
