International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B8, 2012
XXII ISPRS Congress, 25 August - 01 September 2012, Melbourne, Australia
72
that the preponderance of vector (except winter months) was 2
to 3 times higher than the critical density in summer and rainy
months (from March - October) thereby suggesting probability
of successful transmission subject to presence of host and
conducive environmental situation.[2, 4, 6, 8, II]
1.2 Study area and Materials
In the previous study, endemic area of Vaishali district (5
villages) and non-endemic area of Lohardaga district (5
villages) have been taken and studied in detail for
understanding geo-environmental parameters. Based on the
encouraging results, the endemic area of Vaishali district
covering 70.08 sq. km
comprising 12 blocks of all
villages have been taken for
the present investigation (Fig.
2). These villages mostly have
mixed dwelling (house with
cattle shed) with physical
characteristics of the houses
consisting of mud walls, mud
floors, thatched roof etc.
(Shreekant et al, 2010).
Indian Remote Sensing
satellite data of LISS IV (5.8
m) multispectral and Cartosat
- 1 panchromatic data (2.5 m)
acquired during the year 2008 and 2009 over two seasons
(summer and winter) have been used for the present
investigation. Village wise Climatic variables viz. temperature
(min & max) and humidity have also been collected. Field
investigations have been carried out and information on disease
incidence, Man-hour-density (MHD) i.c vector density measure,
peri-domestic vegetation, housing pattern, nature of dwellings,
and living conditions of the population have been collected.
v ry
r - ]
India Â
f
"■* jm
Jharkhand ^
'■'¡JW --—
Bihar
Alp
1
y>rx jJ \-
Lohardaga
Vaishali .jMpi
Fig. 2 Study area
Fig. 3 Housing pattern near Gurhi village showing
peri-domestic vegetation and mixed dwellings.
During the field investigation, it was observed that most of the
villages are having human dwellings with thatched roofs, mud
walls with peri-domestic vegetation (Fig. 3).
1.3 Methodology
A systematic approach has been designed based on the
information generated using satellite data, field and collateral
data and a software package has been developed to estimate
villages at risk in the endemic area. The overall methodology is
given in Fig. 4. Land use / Land cover, Normalised Vegetation
Index, wetlands, rural built up/settlement, peri-domestic
vegetation etc. have been derived from satellite data using
digital image processing techniques with reasonable accuracy.
The understanding of sand fly life cycle became an important
input for characterising geo-environmental parameters in micro
scale in and around endemic villages. The overall methodology
is divided into four different steps namely satellite data
processing, collateral data analysis, statistical analysis and GIS
model development for early warning system.
Fuzzy
Based Risk
Otherground
based
Dwelling condition, Cattle
population, Socio Economic
Conditions
Satellite
S,3ËaÊsàm^
ik. »,
HP
*1
; Xc
V'c
v ir. J
U—s
-A1
Visceral form of disease
development inside the
gut of Phlebotomous
Argentipes takes four to
five days for developing
motile promastigotes in
an adult after feeding
on an infected host.
Climate Data like
Temperature,
Humidity etc.
Kala-Azar Disease
Forewarning
Fig.4 Overall Methodology
Satellite data processing: IRS LISS IV and CARTOSAT -1
satellite data pertaining to two seasons have been rectified using
reference maps and the study area has been extracted. Different
digital enhancement techniques like linear enhancement,
histogram equalisation etc. have been applied on the satellite
data. IRS LISS IV and CARTOSAT - 1 have been merged
using Brovey transform to increase interpretability. Land use /
land cover has been generated applying supervised
classification technique using two seasons satellite data. False
colour composite of IRS LISS IV shows numerous wetlands in
the study area (fig.5). Normalised Difference Vegetation index
has been performed to assess the vegetation vigour of the area
in two seasons.
Fig. 5 False color composite of IRS LISS IV covering
Vaishali distrit
Collateral data analysis: Temperature (Max & Min) and
humidity data, Kala a/.ar disease incidence, cropping pattern,
chemical analysis of soil data and Man-hour-density of vector
(MHD) from most of the villages of Vaishali district have been
collected and analysed. The analysis of MHD and disease
dynamics indicate periodicity at seasonal and inter-annual
temporal scale. From 2003 to 2007, there has been a steady