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RANCHI DISTRICT,JHARKHAND STATE
REPORT ON SLOPE, ASPECT AND ALTITUDE
OF
JHARKHAND SPACE APPLICATIONS CENTER (JSAC)
REMOTE SENSING INSTRUMENTS (An ISO 9001:2008 Company)
Plot#7,Type-I, Industrial Estate, Kukatpally,HYDERABAD-500072
Prepared By
Prepared For
Dept. of Information Technology, Govt. of JharkhandRANCHI - 834004, JHARKHAND
RANCHI DISTRICT,JHARKHAND STATE
REPORT ON
SLOPE, ASPECT AND ALTITUDE OF
JHARKHAND SPACE APPLICATIONS CENTER (JSAC)
REMOTE SENSING INSTRUMENTS (An ISO 9001:2008 Company)
Plot#7,Type-I, Industrial Estate, Kukatpally,HYDERABAD-500072
Prepared By
Prepared For
Dept. of Information Technology, Govt. of JharkhandRANCHI - 834004, JHARKHAND
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA. i
ACKNOWLEDGEMENT On behalf of Remote sensing instruments (RSI) Hyderabad, I express my
heartfelt gratitude to Sri A.T. Jeyaseelan, Director, and scientists of JSAC,
Ranchi, for giving opportunity to associate myself and my colleagues in the
valuable endeavor of generating data base on slope under the data base
generation. I am sure that the work done will be useful and fulfill the
requirements. Throughout the study, the officials of JSAC have been very helpful
and offered their valuable suggestions. I am thankful to all of them.
I shall be failing in my duty, if I do not appreciate the help rendered by my
colleagues at RSI worked with great team spirit to complete this project.
for REMOTE SENSING INSTRUMENTS
B.V.RAMANA KUMAR General Manager
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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LIST OF CONTENTS
Chapter
No. Description Page No.
List of Tables iii
List of Figures iii
List of Plates iv
List of Annexure iv
Executive Summary v
How to Use This Report vii
Chapter-1 Introduction 1
Chapter-2 Geographical Setting 3
Chapter-3 Methodology 8
Chapter-4 The Slope, Aspect and Altitude 16
Chapter-5 Impact of Slope on Land Use and Socio Economic
Status 22
Chapter-6 References 24
Annexure 25
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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LIST OF TABLES
Table No. Description Page No. Table-1 Administrative Set-up of Ranchi District 3
Table-2 Distribution of Slope Categories in Ranchi District 16
Table-3 Classification of Slope Categories based on
Slope Percentage 26
Table-4 Contour Spacing for Slope Categories on 1:50,000
Scale Toposheet with 20m Contour Interval 26
Table-5 Attribute Table for Slope 27
Table-6 Structure of the Data Base Table 28
Table-7 Colour Scheme for Slope Map 28
LIST OF FIGURES Figure No. Description Page No.
Figure-1 Flow Chart for Slope Mapping 9
Figure-2 Distribution of Slope Categories in Ranchi District 17
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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LIST OF PLATES
Plate No. Description Page No. Plate-1 Location Map of Ranchi District 4
Plate-2 Base Map of Ranchi District 7
Plate-3 Toposheet Index of Ranchi District 10
Plate-4 Slope Map of Ranchi District 18
Plate-5 Altitudinal Zonal Map of Ranchi District 20
Plate-6 Slope, Aspect and Altitude Map of Ranchi Toposheet
(73 A/11) 21
Plate-7 IRS P-6 LISS III Satellite Imagery of Ranchi District 23
LIST OF ANNEXURE Serial No. Description Page No.
1 Tables of Technical Guidelines 25
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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EXECUTIVE SUMMARY
Remote Sensing Intruments (RSI), Hyderabad carried out Slope
mapping of Ranchi district under the “Slope Analysis and Creation of GIS Database on Slope” programme at the instance of Jharkhand Space
Applications Center (JSAC), Ranchi. Ranchi district is located in the South
Chotanagpur division of Jharkhand State, between 22052” to 23043” north latitude
and between 84051” to 85055” east longitude, covering an area of 5025Km2 in the
tribal belt of Chotanagpur Plateau. Slope mapping of this district has been carried
out by visual interpretation of Survey of India Toposheets numbering 73A/14,
73A/15, 73A/16, 73E/2, 73E/3, 73E/4, 73E/6, 73E/7, 73E/8, 73E/10, 73E/11,
73E/12, 73E/15, 73E/16, 73F/9 and 73F/13 on 1:50,000 scale. The Slope
categories have been delineated on quality tracing films with precision and
accuracy by the visual analysis of the contour spacing on Survey of India
Toposheets on 1:50,000 scale. In addition to slope categories, aspect, altitudinal
zones and base details like settlements, major roads, railway lines and major
water bodies are also mapped, from those toposheets. These visually interpreted
and mapped features are validated by limited field checks carried out by the
subject specialists. Quality checking has been carried out by the subject experts
for each toposheet, at different stages of mapping. Boundary matching with
adjacent sheets has been carried out such that the slope categories should be
continuous in side-by-side toposheet/ district / commissionaries. The interpreted
tracing films have been scanned, geo-referenced, digitized, brought into GIS
environment and database has been created to each and every feature. Finally
district wise and toposheet wise Slope, Aspect and Altitude maps have been
generated in the GIS environment. .
The entire information is compiled in the form of a report and presented in
the next few Chapters. The information compiled would be very useful in
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assessing the existing slope categories and helpful for management and
developmental practices.
The salient findings of this study are:
1. More than 2/3 part (i.e., 69.86%) of the Ranchi district is covered by
nearly level (0-1% slope) and very gently sloping (1-3% slope) ground.
2. Moderately sloping (5-10% slope) ground is located in the central part
of the district.
3. Strongly sloping to very steep sloping (>10% slope) ground is located
mostly along northern and southern boundaries and in the eastern part
of the district.
4. Major part of the district is in the altitudinal zone of 200-800m.
5. A minor part of the district is in the altitudinal zones of 100-200m and
800-1100m. The altitudinal zone of 100-200m is located in two patches
along the eastern boundary of the district and 800-1100m zone is
mostly along the boundary of this district.
6. Ranchi City is located in the altitudinal zone of 600m to 700m.
The entire data is presented in this report, in the form of text, tables,
figures and plates.
The report and maps will provide exhaustive information and could be
efficiently used for evolving Management and Developmental plans of the
available resources.
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HOW TO USE THIS REPORT
• From the list of contents, tables, figures, plates and annexure, what data is
available and where it is located.
• Brief methodology and salient findings of this study are given in the
Executive Summary.
• The necessary of slope mapping and scope of the work is mentioned
under Chapter-1 (Introduction).
• The location, extent, area, administrative setup, physiography, drainage,
geology, climate and transport network is mentioned under Chapter-2
(Geographical Setting).
• The detailed methodology of slope mapping and creation of database on
slope is mentioned under Chapter-3 (Methodology) with flow chart.
• Findings of this study are given in the Chapter-4 (The slope, aspect and
altitude).
• Classification of slope categories and distribution of slope categories in
Ranchi district with area and percentage are given in the form of tables
and figures.
• Location map, toposheet index, base map, soil map and altitudinal zonal
map of Ranchi district and slope, aspect and altitude map of one
toposheet are shown in plates.
• Impact of slope on land use and socio economic status is mentioned in
Chapter-5.
• Field photographs are provided in appendix.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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CHAPTER – 1
INTRODUCTION Jharkhand is a prosperous state with rich natural resources and extensive
variability in terrain characteristics and associated ecosystems. The state
extends over a geographical area of 79,714sq.km and currently supporting a
projected human population of 2,69,09,428. The state frequently faces natural
calamities such as drought, floods besides the local-specific hazards of industrial
emissions and pollutants, epidemics, fires, accidents etc. The hazards/disasters,
which occur often, though confronted and managed, but needs proper planning,
organisation and implementation strategy. Such situations can certainly be
improved if cause and effect relationships are analysed and understood properly
for gearing up the administration and the infrastructure for drawing appropriate
action plan. This calls for a critical evaluation of the existing situation in terms of
status of the natural resources and its spatial distribution in relation to socio-
economic conditions.
In order to assess the implications of occurrence of natural hazards, one
needs a critical analysis of the situation for which an information base is
essential. Such information base should comprise both spatial and non-spatial
data related to natural resources, infrastructure and the associated socio-
economic parameters. The creation of database would involve generation,
compilation, storage and retrieval facilities, which have, direct and indirect
bearing on the disaster under study.
The generation of spatial information on natural resources has become
handy with the advent of satellite remote sensing which coupled with GIS
technology has enhanced the data storage, retrieval and data analysis. Further,
creation of computerized data base adds a new dimension to the dissemination
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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of information in the form of networking for the free flow of data and information
exchange for speeding up implementation programmes.
In view of the fact that the modern information technology such as Remote
Sensing and Geographic Information System (GIS) have a prominent role to play
in terms of data collection, formatting, storage, manipulation, transmission,
updating, analysis and query development and network / communication link-
age, The Government of Jharkhand has entrusted Jharkhand Space Applications
Center (JSAC), Ranchi, the task of “Slope Analysis and Creation of GIS Database on Slope” for the state. The database thus generated would be
extremely useful to the district authorities for planning and decision-making.
For ‘Slope Analysis and Creation of GIS Database on Slope’, Jharkhand
Space Applications Center (JSAC), Ranchi has identified the different vendors
who are recognised by the Department of Space, Government of India. One of
the vendors is Remote Sensing Instruments (RSI), Hyderabad. South
Chotanagpur Commissionaire covering districts of Lohardaga, Gumla, Simdega,
Khunti and Ranchi has been assigned to Remote Sensing Instruments (RSI),
Hyderabad.
Scope of work: The scope of the work is
• Visual interpretation of Survey of India Toposheets for generation of
Slope, Aspect and Altitude Maps on 1;50,000 scale.
• The interpreted toposheets should be validated by limited field checks.
• Boundary matching of individual toposheet/ district / commissionaries and
state.
• GIS database creation for Slope, Aspect and Altitude.
• Generation of district wise brief reports on Slope, Aspect and Altitude.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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CHAPTER – 2
GEOGRAPHICAL SETTING
Location & Extent: Ranchi district is one of the oldest districts. It is situated in
the central portion of the Jharkhand state and surrounded by Chatra, Hazaribagh
and Ramgarh districts in the north, West Bengal and Saraikela district in the east,
Khunti and Saraikela districts in the south and Latehar, Lohardaga and Gumla
districts in the west. It is located in the South Chotanagpur division of Jharkhand
State, between 22052” to 23043” north latitude and between 84051” to 85055” east
longitude, covering an area of 5025Km2 in the tribal belt of Chotanagpur Plateau.
Location map of Ranchi district is shown as Plate-1.
Administrative Set-up: Ranchi district is divided into Ranchi and Bundu
subdivisions and each subdivision is further divided into blocks. The details of
the blocks are shown in the Table-1
Table-1 Administrative Set-up of Ranchi District
Subdivision Block
Ranchi
1 Kanke 2 Ratu 3 Chanho 4 Mandar 5 Lapung 6 Burmu 7 Bero 8 Namkum 9 Ormanjhi
10 Angara 11 Silli
Bundu 1 Bundu 2 Sonahatu 3 Tamar
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Plate-1 Location Map of Ranchi District
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Ranchi district contains 1319 villages spread over in 298 Gram
Panchayats. Ranchi is the only city and municipal corporation in the district.
Ranchi city is the capital of Jharkhand state and head quarter of the district.
Physiography: The landscape of the district is formed of hills and undulating
terrain of Ranchi Plateau. Ranchi plateau is the largest plateau in Jharkhand.
The uplands of this plateau are known as Tanrs and the lowlands are locally
known as Dons. These lowlands have a number of small hill blocks covered with
forests.
Drainage: Swarnrekha river originates near Ratu. It flows in eastern direction
until it descends at Hundru fall, then it enters into the Singhbhum district. Sankh
river originates in the northwestern part of the district near the Rajadera plateau.
South Koel rises near Mandar and flows towards north in Ranchi district.
Geology: Geologically Ranchi district is comprised with Chotanagpur Gneissic
Complex of Archaean system. Granite gneiss constitutes the geological
formation to a major extent of the district.
The most important mineral occurs in the district is bauxite. Other minerals
which are found in the district are limestone and manazite.
Climate: The climate of Ranchi district comes under subtropical semi-arid type.
The mean annual temperature is 24.50C. The temperature varies from 20.60C to
37.20C in summer and 10.30C to 22.90C in winter. The mean summer
temperature is 280C and the mean winter temperature is 190C. The district
receives annual average rainfall of 1530 mm with the maximum rainfall occurring
in the months of July-August and the minimum in the month of March.
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Transport Network: Ranchi district is well connected with good network of
communication facilities. National Highway No. 23 and 33 passes through the
district and Ranchi city. Ranchi district is having a railway network. Ranchi city is
connected by rail with Dhanbad and Rourkela, which are located on main rail
lines. Birsa Munda Airport is located at Ranchi. Ranchi is also connected by air
with Patna, Kolkota, Delhi and Mumbai. Base map of Ranchi district is shown as
Plate-2.
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Plate-2
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CHAPTER – 3
METHODOLOGY
Slope is an important parameter in planning developmental activities, soil
conservation measures and in disaster mitigation studies. Slope is an indicator of
relief energy because it helps in the formation of erosional as well as depositional
features. Slope is also an important indicator to understand the amount of
precipitation that goes as runoff, land capability and land irrigability of the area
and also to understand the vulnerability to natural hazards like landslides and
floods.
Slope mapping of Ranchi district has been carried out by visual
interpretation of Survey of India Toposheets on 1:50,000 scale. The methodology
followed for the preparation of slope Maps is given in the flow chart as Figure – 1
and the same has been described below.
Identification of Required Toposheets: Toposheets pertaining to Ranchi district have been identified by overlaying
district boundary on the toposheet grid. Those are 16 toposheets viz., 73A/14,
73A/15, 73A/16, 73E/2, 73E/3, 73E/4, 73E/6, 73E/7, 73E/8, 73E/10, 73E/11,
73E/12, 73E/15, 73E/16, 73F/9 and 73F/13. Toposheet index of the district is
shown in the Plate-3.
Procurement of Toposheets:
Toposheets pertaining to Ranchi district have been procured from the
Survey of India. These toposheets are with contour interval of 20m on
1:50,000scale and are surveyed in different years.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Figure-1 Flow Chart for Slope Mapping
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Plate-3 Toposheet Index of Ranchi District
Delineation of Slope Categories by Visual Interpretation: Slope is a measurement of gradient of steepness between two places or points
on land surface. Slope is measured as ratio of vertical interval and horizontal
distance of a given surface. The vertical drop can be estimated / measured from
the contour intervals and the horizontal distance in between the contours can be
measured from maps by multiplying the map distance with the scale factor. Slope
is expressed in percentage or degrees.
Contour interval in meters
Slope Percentage = -------------------------------------------------------------------------- X 100 Distance between the contours in meters x Scale factor
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Slope has been classified into seven categories based on the percent of
slope. Jharkhand State Remote Sensing Application Centre (JSAC), Ranchi, has
provided the classification system and is given in the annexure as Table-3.
The contour spacing for each slope category has been calculated on
1:50,000scale toposheet with 20m contour interval and their details are given in
the annexure as Table-4.
Based on the contour spacing, slope categories have been delineated on
good quality tracing films with precision and accuracy by the visual analysis of
Survey of India Toposheets on 1:50,000 scale with 20m contour interval.
Demarcation of Aspect Direction: Slope aspect is the direction toward which
the surface of the earth faces. It has a bearing on precipitation of rainfall and
vegetation type, growth and conditions. It is also very important to know the slope
direction in order to understand certain features like soil erosion and vulnerability
to land slide.
The direction (slope aspect) is expressed as an angle between 0 degree
and 360 degrees (measured clockwise from true north) or as a compass point
such as east or north-northwest.
Aspect is directly derived from the toposheet and marked on the slope map
for the categories having more than 15 percent of slope. Aspect is marked in
arrow symbol facing four directions such as
• north for north, northeast and northwest facing slopes
• east for east facing slopes
• south for south, southeast and southwest facing slopes and
• west for west facing slopes
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Demarcation of Altitudinal Zones: Contour lines with 100m interval have been
derived from the toposheet and marked on the slope map, for generating
altitudinal zones.
Ground Truth: The limited ground truth has been carried out by the subject specialists to
verify the accuracy of slope categories. The actual slope on the ground has been
measured with the instruments like Abney level, Clinometers etc., and the details
have been noted in the field dairies. Representative photographs for each slope
category have been taken with their precise location, recorded through handheld
GPS receivers. Then all the slope categories of each map have been finalized by
incorporating necessary modifications collected in the field.
Quality Checking: Internal quality checking has been carried out by the subject experts for
each toposheet, at different stages of mapping. Then necessary modifications
have been incorporated in each map as suggested in the quality checking.
Boundary Matching: After finalizing of the interpreted slope map, boundary matching with
adjacent sheets has been carried out, such that the slope categories and
altitudinal zones are continuous, in side-by-side toposheet/ district /
commissionaries.
Quality Assurance and Standardization: External quality checking of the slope, aspect and altitudinal zones on
tracing films have been carried out, for each toposheet, by the Quality Assurance
and Standardization (QAS) team, constituted by the Director, JSAC, Ranchi.
Then necessary modifications have been incorporated in each map as per the
QAS report.
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Scanning: The tracing films containing the finalized slope polygons, aspect and
altitudinal zones have been scanned in grey scale at 150 DPI resolution and
converted into Tiff format (in soft copy) .
Geo-Referencing: Correlating data to the real world co-ordinates with a specific projection
and specified units is called geo-referencing. There is no correlation between
Survey of India grid and scanned data (Tiff file). The feature on the Tiff file
doesn’t have any reference to real world co-ordinates. Unless until, Tiff files are
geo-referenced, they cannot be arranged sequentially or overlaid one upon
another for any further analysis. Correlation of the image to user specified
referencing system, with projection has been taken up. Each tiff file of the scanned slope maps has been Geo-referenced with the
co-ordinates of its respective toposheet with UTM (Universal Transverse
coordinate Mercator) projection system by using Erdas Imagine software. Zone 5
is used for the Jharkhand state of 840 E to 940 E extent with 870 E as Central
meridian, WGS8 as Datum and WGS84 as Spheroid.
Digitization: Digitization is the process of capturing the point, line and polygon features
as vectors. The manual digitization method is followed for vectorization of visually
interpreted slope maps. The scanned interpreted slope sheet has been displayed
in the background; the required environment settings for digitization are set and
the required features like slope polygons, aspect symbols, altitudinal zones and
base details like major roads, railway lines, rivers, lakes, reservoirs and
settlements have been captured into different layers. Topology was built between
different polygons and the overshoots and undershoots have been edited.
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During the digitization, care has been taken that the vector lines, points,
polygons sit exactly on top of the scanned raster data, without any shift between
raster and vector data, on scale of digitization.
GIS Data Base Creation: Attributions like slope category, altitudinal zone value, aspect direction,
settlement name, water body etc., details have been added to the digitized vector
data. During this process care has been taken that there is no miss matching
between vector data and respective raster data and all the attributes are tagged
correctly and complete.
Then prescribed attribute table has been attached to the vector data in Arc
GIS environment. The attribute table for slope and structure of the data base
table are provided by the JSAC and they are shown in the annexure as Table-5
and Table-6.
Map Composition: Map composition of the slope, aspect and altitude map has been carried
out for each toposheet and district mosaic in MXD format in Arc GIS environment
as per the prescribed MOCK-UP provided by JSAC. Colour scheme provided by
JSAC for slope map is shown in the annexure as Table-7. Each map comprises
of map elements like slope theme, aspect direction, altitudinal zones, overlay of
base map features like major settlements, major roads, railway line and water
bodies, legend, index map, location map, sources of data, toposheet number,
commisionarie name, district name, theme title, scale bar and north arrow. A
sample map covering Ranchi town is shown as Plate-6.
Care has been taken that all the information shown in the map layout is
complete and perfect with respect to Mock-up prescribed by the JSAC. After
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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internal quality checking of the each map layout, they have been converted into
pdf format.
Quality Assurance and Standardization: External quality checking of the slope, aspect and altitude maps in pdf
format, has been carried out for each toposheet and district mosaic, by the
Quality Assurance and Standardization (QAS) team, constituted by the Director,
JSAC, Ranchi. Then necessary modifications have been incorporated in the map
layout as per the QAS2 report.
Generation of Maps: After incorporating the modifications as per QAS2 report, hard copies of
toposheet wise and district mosaic maps of slope, aspect and altitude have been
generated on coated paper. District wise report on slope, aspect and altitude has
been prepared as per the format provided by JSAC.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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CHAPTER – 4
THE SLOPE, ASPECT AND ALTITUDE
Slope: More than 2/3 part (i.e., 69.86%) of the Ranchi district is covered by nearly
level and very gently sloping ground. Moderately sloping area is located in the
central part of the district. Strongly sloping to very steep sloping ground is located
mostly along northern and southern boundaries and in the eastern part of the
district. The distribution of the slope categories, in this district, with their area and
percentages are shown in the Table -2 and Figure-2. The slope map of Ranchi
district is shown as Plate-4. Toposheet wise map covering Ranchi city, with slope
details, is shown as Plate-6.
Table-2 Distribution of Slope Categories in Ranchi District
Serial No. Slope Category Area
(in sq.km) Percentage
(%) 1 Nearly Level (0-1%) 768.02 15.28
2 Very Gently Sloping (1-3%) 2742.83 54.57
3 Gently Sloping (3-5%) 282.51 5.62
4 Moderately Sloping (5-10%) 420.85 8.37
5 Strongly Sloping (10-15%) 331.50 6.60
6 Moderately Steep to Steeply
Sloping (15-35%) 306.61 6.10
7 Very Steeply Sloping (>35%) 173.49 3.45
Total 5025.82 100.00
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Figure-2
15.28%
54.57%
5.62%
8.37%
6.60%
6.10%3.45%
Distribution of Slope Categories in Ranchi District
Nearly Level (0‐1%)
Very Gently Sloping (1‐3%)
Gently Sloping (3‐5%)
Moderately Sloping (5‐10%)
Strongly Sloping (10‐15%)
Moderately Steep to Steeply Sloping (15‐35%)
Very Steeply Sloping (>35%)
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Plate-4
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Aspect: Aspect direction changes from place to place in this district. Toposheet
wise map covering Ranchi City, with aspect symbols, is shown as Plate-6.
Altitude: Ranchi district is located in the altitudinal zone of 100m to 1100m. In it,
major part of the district is in 200-800m zone and a minor part is in 100-200m
and 800-1100m zones. 100-200m zone is in two patches along the eastern
boundary of the district. 800-1100m zone is also located mostly along the
boundary of this district. Ranchi city is located in the altitudinal zone of 600m to
700m. Altitudinal zonal map of Ranchi district is shown as Plate-5. Toposheet
wise map covering Ranchi city, with altitudes, is shown as Plate-6.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Plate-5
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.
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Plate-6 Slope, Aspect and Altitude Map of Ranchi Toposheet (73 E/7)
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.
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CHAPTER – 5
IMPACT OF SLOPE ON LAND USE AND SOCIO ECONOMIC STATUS
Land use/land cover of the district is mainly agriculture and forestry. By
comparing the slope map (Plate-4) and IRS P-6 LISS III satellite imagery (Plate-
7) of Ranchi district, it is evident that, strongly sloping to very steep sloping
(>10% slope) ground is covered by forest. So, there is a direct impact of slope on
the land use of the district. In the same way, where ever the nearly level to very
gently sloping (0-3% slope) ground is there in the slope map (Plate-4),
agricultural development is observed in the IRS P-6 LISS III satellite image
(Plate-7).
In Ranchi district, 74% of the population lives in the villages and totally
depend on agriculture and related activities. Agriculture is practiced mainly in
plains. However, cultivation is also taken up to some extent in gently sloping
areas and in moderately steeply sloping areas. There is a scarcity of sufficient
and dependable source of irrigation. There are no irrigation projects in this
district, may be due to erratic rain and other unfavorable conditions. Due to lack
of good irrigational facilities, the farmers are not able to grow enough food grains
to meet their requirement. The main crop grown in the district is rice followed by
maize, bajra, pulses, wheat, oil seeds (til and mustard) and vegetables. Around
50% of the households of this district are below poverty line. For want of
irrigational facilities the farmers are traditionally been doing mono cropping,
resulting in poor economy. In the larger interest of the rural economy, agriculture
needs to be strengthened and one of its most important inputs ie, irrigation
facilities needs to be given due priority.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.
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Plate-7 IRS P-6 LISS III, Satellite Imagery of Ranchi District
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.REMOTE SENSING INSTRUMENTSHYDERABAD, INDIA.
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CHAPTER – 6
REFERENCES
1. Unpublished technical reports on slope mapping.
2. Technical guidelines for execution of slope analysis and creation of GIS
database on slope, Jharkhand Space Applications Center (JSAC), Govt.
of Jharkhand, Ranchi.
3. Jharkhand.nic.in
4. Singh, Sunil (2005). Inside Jharkhand, Crown Publications, Ranchi,
Jharkhand.
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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ANNEXURE
Tables of Technical Guidelines
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Table-3 Classification of Slope Categories based on Slope Percentage
Serial No. Slope Category Slope % 1 Nearly Level 0 - 1
2 Very gently Sloping 1 - 3
3 Gently Sloping 3 - 5
4 Moderately Sloping 5 - 10
5 Strongly Sloping 10 - 15
6 Moderately Steep to Steeply Sloping 15 - 35
7 Very steeply Sloping > 35
Table-4
Contour Spacing for Slope Categories on 1:50,000 Scale Toposheet with 20m Contour Interval
Slope Category
Lower and Upper Limit of Slope Percent
Lower and Upper Limit of Contour Spacing
1 0 – 1 percent More than 4 cm
2 More than 1 percent and
up to 3 percent
More than 1.33cm and
up to 4cm
3 More than 3 percent and
up to 5 percent
More than 0.8cm and up
to 1.33cm
4 More than 5 percent and
up to 10 percent
More than 0.4cm and up
to 0.8cm
5 More than 10 percent and
up to 15 percent
More than 0.26cm and
up to 0.4cm
6 More than 15 percent and
up to 35 percent
More than 0.11cm and
up to 0.26cm
7 More than 35 percent 0.11cm and less
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Table-5 Attribute Table for Slope
SLP-CODE Slope % Aspect
01-00 0 - 1
02-00 1 - 3
03-00 3 - 5
04-00 5 - 10
05-00 10 - 15
06-00 15 - 35
06-01 North (NE&NW)
06-02 South (SE&SW)
06-03 East
06-04 West
07-00 > 35
07-01 North (NE&NW)
07-02 South (SE&SW)
07-03 East
07-04 West
98-98 Habitation
99-9 Water Body
Report on Slope, Aspect and Altitude of Ranchi District, Jharkhand State
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Table-6 Structure of the Data Base Table
Field Name Field Type Key Y/N Remarks
SLP-CODE 4,4,C Y Feature Code
SLOPE 30,30,C N Slope in Percent
ASPECT 20,20,C N Aspect Direction
Table-7 Colour Scheme for Slope Map
Serial No. Slope Category Colour Scheme
1 Nearly Level Yellow
2 Very gently Sloping Yellow
3 Gently Sloping Yellow
4 Moderately Sloping Yellow
5 Strongly Sloping Orange
6 Moderately Steep to Steeply Sloping Brown
7 Very steeply Sloping Red
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