t v ramachandra, bharath setturu, tara n...

T V Ramachandra, Bharath Setturu, Tara N M ENVIS-SAHYADRI: Western Ghats Biodiversity & Ecology

EWRG, ([email protected]; [email protected])

Center for Ecological Sciences, IISc, BangaloreE Mail: [email protected]; [email protected]

[email protected]; [email protected]

Tel: 91-080-2293099/22933503

GREEN SKILL DEVELOPMENT

UNDERSTANDING GRIDSS

• QGIS – INTRODUCTION

• EXPLORING QGIS – FUNCTIONS

• ROI/AOI

• GRID CREATION

• DATA INGESTION

• SPATIAL ANALYSES

• VISUALISATION

• IMPROVE IF REQUIRED

GRIDS through Open source GIS- QGIS

oQuantum GIS (QGIS; https://qgis.org/downloads/ ) is a spatial analyses tool

for managing geographical data, 3-D analysis, statistical analysis

Supports vector, raster, and database formats.

oIt is an official project of OSGEO (Open Source Geospatial Foundation)

and available under GNU General Public License;

oQGIS is translated into 70 languages (Hindi, Tamil, Malayalam, Telugu)

oPlug-ins available to expand compatibility and functionality.

3

QGIS is multiplatform GIS that runs on

Qgis

Unix

Windows

Mac OSX

Linux

ANDROID version of Qgis is also available for mobile phones4

WEB (www.qgis.org/en/)

QGIS has active community support, update and upgrades

5

WIKI

6

BLOG BUGS

7

USER MAILING LIST

8

QGIS - Getting Started …

Install - Get the latest information of binary packages at the QGIS website at

https://qgis.org/downloads/

EXPLORE QGIS

12

3

4

5

Menu Bar

Tool Bar

Map Legend

Map View/ Canvas area

Status Bar 11

The menu bar provides access to numerous QGIS features.

The toolbars offers additional tools for interacting with the map. Hold

the mouse over the particular icon, a short description of the tool’s

purpose will be displayed.

Every menu bar can be moved around according to your needs.

Additionally every menu bar can be switched off using your right mouse

button context menu holding the mouse over the toolbars

The map legend area sets the visibility

QGIS - maps are displayed in map canvas area

The map overview panel provides a full extent view of layers added

The status bar shows the current position in map coordinates12

GIS Data Formats –

raster, vectorRaster

• Data are divided into cell, pixels, or elements

• Cells are organized in arrays

• Each cell has a single value

• Perhaps the most common example of raster data is a digital image

Vector

Data are associated with points, lines, polygons or boundaries enclosing

areas

Points are located by coordinates

Lines are described by a series of connecting vectors (line segments described

by the coordinates of the start of the vector, its direction, and magnitude or

length)

Areas or polygons are described by a series of vectors enclosing the area13

Spatial Features

POINT

LINE

POLYGON

14

QGIS: DATA TYPES

MAP

DATA

• Contains the location and shape of geographic features.

• Maps use three basic shapes to present real-world features:

points, lines, and areas (called polygons)

ATTRIBUTE DATA

• Tabular data is the descriptive data that GIS links to map features.

• Ex specific areas information like states, census tracts, cities, and so on and often comes packaged with map data.

IMAGE DATA

• Features are represented as a matrix of cells

• Image data ranges from satellite images and aerial photographs to scanned maps

15

Data required for GRID analysisTheme Collection method Source of data

LAND

LAND USE MAP

(2017/18)

IMAGE ANALYSIS EARTHEXPLORER.USGS

.GOV;

NRSC.GOV.IN

(FREE/PURCHASE-HIGH

RESOLUTION)

ECOLOGY

FLORA

FAUNA

CONSERVATION

RESERVES

FIELD ANALYSIS

LITERATURE REVIEW

http://www.iucnredlist.org/

BSI/ZSI REPORTS

http://www.wiienvis.nic.in/

https://www.protectedplan

et.net/

SOCIO ECONOMIC DATA LITERATURE REVIEW;

STATE STATISTICAL

DEPARTMENTS

http://www.surveykshan.go

v.in/

SURVEY OF INDIA

REPORTS

ENERGY IMAGE ANALYSIS

FIELD ANALYSIS

NASA/USGS PORTALS

HYDROLOGY

RAINFALL

FIELD ANALYSIS

IMD DATA SETS

STATE STATISTICAL

DEPARTMENTS 16

India Administrative Boundaries & Other Data

• http://www.diva-gis.org/Data

• http://www.gisinindia.com/directory/gis-data-

for-india

• https://www.statsilk.com/maps/download-

free-shapefile-maps

• http://projects.datameet.org/indian_village_b

oundaries/ka/#download

17

Diva GIS

• Open DIVAGIS (http://www.diva-gis.org/data)

18

Ensure Data integrity

‘Diva’ for Spatial Analysts

• Download data from DIVAGIS

19

When data availability

itself poses serious

challenge, DIVA offers

solution

Vector dataStep 1Step 2

Step 3

21

Improving the performance

Select properties by right click on the layer name; the properties

dialogue box will be opened with multiple options

i.e. General, Styles, Lables, Attributes, Metadata, Actions, Diagram

overlay.22

Overlay – multiple data We can overlay one vector on another by adding a vector layer.

Database ingest-querying

• Data ingestion- obtain, import and process data.

• Process – data normalisation and aggregation

25

Select features using an expression

Projections – Earth is SPHEROID!

You can change projection by right click properties or save as option to

save a new file with you own projection.

The global default CRS is EPSG:4326 - WGS 84 (proj=longlat +ellps=WGS84

+datum=WGS84 +no_defs)

Options for global and project-wide CRS (Coordinate Reference System)

for layers.

allows to define custom coordinate reference systems and supports on-the-

fly (OTF) projection of vector and raster layers - Can display layers (with

different CRS) and options for overlay.

QGIS supports >2,700 known CRS. Definitions for each of these CRS are

stored in a SQLite database that is installed with QGIS. 29

The REGION OF INTEREST – DISTRICT ( CHOOSE your STATE, District (ROI/AOI)

CREATE GRIDS

LOCATE VECTOR TOOLS

STEP 1

STEP 2

Edit - Attribute Information

Start Editing Add column

Add Attribute

InformationSave edits and

stop toggle edit

37

Map Calculator

38

I

M

P

O

P

R

T

I

N

G

F

I

E

L

D

D

A

T

A

Real world phenomena are continuous - elevations, soils, temperatures,

rainfall etc. But, available data are – discrete points

Field measurements are at various points along the surface

The intermediate values are inferred by a process called ‘interpolation’.

In QGIS, interpolation is achieved using the built-in Interpolation plugin.

Interpolation of Discrete point data to the continuous surface

Interpolation is a process of using points with known values to

estimate values at other unknown points.

42

INTERPOLATION: Inverse Distance Weighted (IDW)

The sample points are weighted during interpolation such that the

influence of one point relative to another declines with distance from the

unknown point.

43

INTERPOLATION: Triangulated Irregular Network (TIN)

TIN interpolation is another popular tool tries to create a surface formed

by triangles of nearest neighbor points.

The circumcircles around selected sample points are created and their

intersections are connected to a network of non overlapping and as

compact as possible triangles.

44

Import rainfall data and display it

SAVE AS A SHAPE FILE WITH “UTM PROJECTION”

RIGH CLICK ON LAYER CLICK ZOOM TO LAYER

Open attribute table to see the details

46

Click on Raster Interpolation Interpolation

47

Change colors as per requirements

49

CREATE VECTOR DATA - Digitize

•QGIS supports digitizing from a raster or vector layer. It support

editing include shape files, Post GIS, and GRASS data.

•The attribute values in new table allow real, integer, and string data

types. Point, line, and polygon features are supported. Attributes are

entered as features are created.

Editing features include,

• moving vertices or points,

• inserting new points where needed,

• deleting unnecessary points,

• deleting entire features,

• cut or copy features from one layer and paste to another,

• multiple features can be copied/pasted in one operation

50

Digitise

• Process of representing features as points, lines and

polygons.

Example: Light towers,

Bus stops, Schools etc

Example: Road network,

Stream Network etc.

Example: Forests, political

boundaries .. etc

(x1,y1)

(x2,y2)

(x3,y3) (x3,y3)

(x1,y1)

(x2,y2)

(xn,yn)

(xn,yn)

(x1,y1)

(x3,y3)(x2,y2)

51

Spatial Data

POINT

LINE

POLYGON

52

PRIMARY DATA – FIELD DATA COLLECTION

Data collection in the field will be carried out to get more

insights in

• FLORA

• FAUNA

• OTHER ELEMENTS

First step in the field is “understanding landscape elements.”

Prioritizing data collection / sampling method

Collecting data

Analyzing data55

LANDSCAPE ELEMENTS: MAJOR GROUPINGS I. Coastal elements (natural) 1. Sandy shore

2. Rocky shore

3. Estuary

4. Coastal lowlands

II. Forests 1. Evergreen

2. Semi-evergreen

3. Moist deciduous

4. Secondary moist-deciduous

5. Dry deciduous

III. Aquatic (fresh water) 1. Large streams

2. Rivers

3. Waterfalls

4. Ponds, lakes & reservoirs

IV. Scrub and savanna 1. Dense scrub

2. Isolated shrubs

3. Temporary rock pools

4. Wet rocks during rains

5. Grassy patches

V. Agriculture 1. Fields of seasonal crops

2. Fallow fields

3. Plantation crops (areca, coconut, banana, groves of fruit

trees)

4. Irrigation canals

VI. Forest plantations 1. Teak

2. Acacia

3. Casuarina

4. Mixed/others

56

Flora - VEGETATION

57

Details to be collected during field Sampling

1. Date…………………………………….

2. Hamlet……………………………………

3. Village………….........................

4. Taluk…………………………………

5. Range………………………………

6. Lat……………….Long………...............

7. Alt:

8. Forest patch type :

9. Legal status:

10.Transect No:

11.Transect Length:

12.Nature of the terrain: Steep slope/Moderate/Low to flat/Undulating

13.Is there perennial stream through the transect?

14.Local name of the locality surveyed:(Kan, Bena, Betta, Hakkalu, Kodlu etc.)

15.Litter cover on the ground: (gms):0-200/200-400/400-600/600-800/800-1000/>1000

16. Rock outcrops, or rockiness: High/Moderate/Poor to nil

17. Soil erosion on the site: High/Moderate/Least

18. Nearest human habitation (in Km): 58

Details to be collected during field sampling

Tree cut Lopping Fuel extract Litter

collect

Grazing Others

(Name)

Notes on human interference:

Notes on fire incidence:

NTFP collection :

Color of soil :

Nature of soil : Loamy/Clay/Sandy

59

Other details followed during the survey

1. Transects were laid slightly interior leaving

the forest margins in order to avoid forest

edge disturbances.

2. Transects were laid parallel to the slope and

not right angles to slope as the diversity

changes with respect to altitude and slope.

3. Other details such as epiphytes, lianas,

flowering, fruiting etc were also noted

associated with each tree.

4. For buttressed trees measurements were

made above the buttress and for multi-

stemmed trees, girths were measured

separately and basal area should be

calculated separately.60

TRANSACT CUM QUADRAT METHOD

Design of transect cum quadrats

(2 of 5 quadrats of 20 x 20 m only shown).

(Note: A. Tree quadrat, B. Shrub plot, C. Herb plot).

61

• Most of the forest vegetation was sampled using transect-

based quadrats (modified belt transect).

• Along a transect of 180 m, 5 quadrats each of 20 m x 20 m

were laid alternatively on the right and left, for tree study

(minimum girth of 30 cm at GBH (Girth at breast height) or

130 cm height from the ground), keeping intervals of 20 m

length between successive quadrats.

• Within each tree quadrat, at two diagonal corners, two sub-

quadrats of 5 m × 5 m were laid for shrubs and tree saplings

(< 30 cm girth and > 1m height).

• Within each of these shrub quadrats, 2 herb layer quadrats, 1

sq.m area each, were also laid down for herbs and tree

seedlings (< 1m height). Climbers and other associated

species were noted. 62

POINT CENTRED QUADRAT

METHOD

25 m

A

B

ii

i

iv iii

Trees; i, ii, iii, iv- First, second, third and fourth

quadrant; A-Direction of transect; B-distance of

nearest trees from center of point centered quartar.

63

• From each sector, tree data was obtained from 30 points

(with a distance of 50 m between points) covering 1.5

km., of total transect length.

• The advantage of this method is the fastness with which

large distances can be covered in relatively short times

compared to the quadrat method or others.

• At each point along the transect, using two sticks a cross

was made forming four quarters.

• In each quarter-distance to the nearest tree (minimum

GBH of 30 cm) from the central point was measured.

64

• Thus data was derived on four trees at each point and

the distances to these four trees from the central point.

• The mean distance to the trees was estimated by

dividing the total distances to four trees by four from the

point.

• Apart from GBH the heights were also estimated. At

every 3rd point shrub layer (including shrubs and tree

saplings above 1 m height) of 5 x 5 m was studied.

• The tree density was estimated by using the formula:

Number of individuals/Area.

65

QUADRAT DATA SHEET-TREES

Q.NO. Latitude: Longitude: Alt:

Time: Date: Place: Soil sample code:

Sl.No Species GBH Ht. Phenology Climbers Remarks

1

2

3

Canopy Cover: Point

1……………............2………………............3……………………...4………………...5.............

Mean of canopy cover:

Leaf Litter (in grams): 66

SHRUB LAYER

QUADRAT – 1 (5m x 5m)

Sl.No. Species No. Phenology Remarks

QUADRAT - 2, 3, 4


67

HERB LAYER (1m X 1m)

QUADRAT – 1


QUADRAT - 2, 3, 4


68

H’ = -Σ [(ni/N) ln (ni/N)]

Where, H’ = Shannon’s diversity index

ni = Number of individuals belonging to the ‘i’ species

N = Total number of individuals in the sample.

Species diversity

Shannon-Weiner diversity index:

Species diversity index includes both the number of species and number

of individuals in a community.

Diversity is an indicator of status of an ecosystem. It consists of two

components, the variety and the relative abundance of species. The

higher value indicates higher diversity.

Importance Value Index (IVI):

IVI is a significant parameter in any ecological assessment. It is an

indicator of ecological success of the species.

IVI = Relative density + Relative basal area + Relative frequency69

Sl. No Index Formula

1 Relative density Density of species A × 100

Total density of all species

2 Relative frequency Frequency of species A × 100

Total frequency of all species

3 % Evergreenness (trees) No. of evergreen trees × 100

Total no. of trees

4 % Endemism (trees) No. of endemic trees × 100

Total no. of trees

5 Basel area (m²) (GBH)²/4π

6 Relative basal area Basal area (m²) of species A × 100

Total basal area of all species

7 Above Ground Biomass

(AGB) (t/ha) -2.81 + 6.78 (BA)

8 Below Ground Biomass

(BGB) (t/ha) 0.26 × AGB

9 Carbon storage (AGB + BGB) × 0.5

1

70

IMPORT FIELD DATA (GPS) to QGIS

INTERSECTING AND CREATING GRID WISE DISTRIBUTION

71

Import GPS data

Paper Map to Digital Map

Paper Map Digital MapScanning

Printing

Conversion

73

LATITUDE (PARALLELS)

Is a geographic coordinate that specifies the north-southposition of a point on the Earth's surface.

Measured as the angle made between the equatorial planeand the parallel of current location w.r.t center

Varies from 0 – 90 degrees towards north or toward southof the equator

LONGITUDE (MERIDIANS)

• Is a geographic coordinate that specifies the east-westposition of a point on the Earth's surface.

• Measured as the angle made between the greenwitch(prime) meridian and the meridian of currentlocation w.r.t center

• Varies from 0 – 180 degrees towards east or towardwest of the green witch meridian

8-36 lat

68-96 long

74

Reading

Coordinates in

toposheet

• 1: 50000

• Scanned toposheets have

no geographical reference

i.e., they are in the

rectangular coordinate

system

15’

15’

5’

5’

76

Geo referencing: Geo referencing usually refers to the method by which locations in the

raster and vector GIS files are related to real earth-surface positions.

To start geo referencing an unreferenced raster, we must load it using the

button. The raster will show up in the main working area of the dialog. Once

the raster is loaded, we can start to enter reference points.

Using the Add Point button, add points to the main working area and enter

their coordinates

For this procedure you have two options:

a) Click on a point in the raster image and enter the X and Y coordinates

manually

b) Click on a point in the raster image and choose the button from map

canvas to add the X and Y coordinates with the help of a georeferenced map

already loaded in the QGIS map canvas.

c) With the button, you can move the GCPs in both windows, if they are at

the wrong place.

Continue entering points. You should have at least 4 points, and the more

coordinates you can provide, the better the result will be. There are

additional tools on the plugin dialog to zoom and pan the working area in

order to locate a relevant set of GCP points.

•After entering GCP’s click on Settings option in Georeferencing menu bar

select Transformation Settings option.

•A drop box will be displayed and select options as shown in the below

image.

•Specify output file name and

transformation parameters and projection

system then click OK.

QGIS Plugins

Plugin Manager provides a resource to load or unload plugins.

-- Core Plugins are automatically part of every QGIS

distribution. They are written in one of two languages: C++ or

Python.

– External Plugins are currently all written in Python. They

can be added to QGIS using the Plugin Installer.

80

Print Composer

● Simple maplayouts made easy

●Apply map, legend, north arrow and text

● Using external programms (inkscape) for finetuning.

● Lots of paperformats supported

● Logo inclusion, legend, labels, northarrow

● PNG/SVG/PDF support

●Adjustable drawing scale

● Separate DPI settings

81

LEARN AND USE GREEN DATA

FOR SUSTAINABLE GREEN

INDIA

82

THANK YOU

t v ramachandra, bharath setturu, tara n...

Documents