Remote sensing in plants, botany, application in vegetation classification and conservation, basic mechanism of remote sensing,how it works, satellite mapping techniques and aerial mapping
2. Remote sensing is the science of obtaining
information about objects or areas from a distance,
without coming direct contact with the object
3. It can be done with devices on the ground or on
ships, planes and even satellites.
This helps us to give a broad perspective on
vegetation, climatic change, environmental issues
etc.
4. Remote sensors collect data by detecting the
energy that is reflected
Remote sensors can be:
Passive sensors respond to external stimuli
They record natural energy that is reflected or
emitted
Passive sensors
Active sensors
5. Active sensors use internal stimuli to collect data
For example:
A laser beam remote sensing system projects a
laser beam onto the surface of earth and measures
the time it takes for laser to reflect back to its
sensors
6. APPLICATIONS
Remote sensing is used in numerous fields like:
Geography
Earth science (Hydrology, ecology,
oceanography, glaciology, geology)
Military Intelligence
Commercial, economic planning and
humanitarian applications
Vegetation and environment
7. ELEMENTS IN REMOTE SENSING
Energy source
Radiation and atmosphere
Interaction with the target
Recording of energy by sensors
Transmission, reception and processing
Interpretation and analysis
8. DATA ACQUISITION
Data acquisition can be done using:
Radars
Satellites
Ultrasound
Lidar (light detection and ranging)
Photometers and Radiometers
Aerial photographs
Seismographs
Geodetic
9. Electromagnetic energy may be detected either
photographically or electronically
And image produced can be analog or digital
Aerial photographs are examples of analog images,
while satellite images are of digital images
10. SATELLITE SENSORS
They revolve around the earth
The path followed by a satellite is referred to as its
orbit
They are of two types:
Geostationary
Near polar
11.
12. APPLICATION IN VEGETATION CLASSIFICATION
The reflectance quality of a vegetation detected
using remote sensors enables its classification
Green vegetation will reflect more energy than dry
vegetation
Tree leaves and crop canopies reflect more in
shorter radar wavelengths,
While tree trunks and limbs reflect more in longer
wavelengths
13.
14. The density of the tree or plant canopy will affect
the scattering of wavelengths
Thus by analyzing reflectance, we can determine
characteristics of a vegetation.
Moreover, Aerial photographs, color infrared
photographs, black and white infra red photographs
helps to identify species.
They also give the details of branching
characteristics, crown shapes, spatial distribution
and patterns of species.
15.
16. This information along with the topographic
variables obtained through field work is a valuable
tool in vegetation classification
Different types of images will display diverse
characteristics of vegetation
Band 1 of AVHRR (advance very high resolution
radiometer) will allow chlorophyll to absorbed in red
wavelength.
And a low value indicate high concentration of
chlorophyll
17. Similarly, Band 2 of AVHRR include infrared
wavelengths and record the cell structure of the
leaves
High values indicate more growth, indicated by dark
green signatures
While low value are indicated by orange signatures
20. LIMITATIONS
Difficulty in distinguishing fine, ecological divisions
between certain vegetation classes.
If vegetation share common heterogeneous traits
and similar spectral responses, difficulties are
created in classifying vegetations
21. REMOTE SENSING IN ECOSYSTEM MANAGEMENT AND ENVIRONMENTAL
ISSUES
Remote sensing helps in :
Habitat suitability mapping
Monitor habitat loss and fragmentation
Wetland mapping and monitoring
Identifying and monitoring threats
Predicting biodiversity richness
Predicting species presence or absence
22.
23. Provide data on vegetation land cover and
pattern of distribution of plant communities
Mapping and characterizing species habitats
Identifying biodiversity Hotspots at broad spatial
scale
In measuring biological productivity
Forest fire monitoring
24.
25. For establishing base – lines and ongoing
monitoring for deforestation, pollutant emissions,
spread of invasive species, climate change impacts
etc.
Assisting in stratified random sampling strategies
for field inventories.
In carbon sequestration monitoring (
aforestation/deforestation)
In coral reef monitoring
Oil spill verification
26. To monitor marine protected areas
Monitor desertification process
To raise public awareness, e.g. Toms data on
ozone hole, receding glaciers and climate change
It can bring people together across boundaries to
address common problems
Powerful tool for international cooperation
To detect changes in water and to test water quality
27.
28. In Air quality – remote sensing of particulate
aerosols in the atmosphere helps in this
Conservation of endangered species
To identify flood plains
To update highly dynamic, rapidly changing coastal
environment
In distinguishing landscape categories etc.