2. Mangroves in the Map. 2.3 Importance of
2.1 Study objectives:-
Specific objectives of
this study are following:
intent of this study is the detection of area covered by mangroves especially
in Karachi area, adumbrate the existential threats being faced by mangroves,
comparison of past and present mangrove covered areas, and suggestions for
their betterment in future. They
provide various ecological and economical ecosystem services contributing to
coastal erosion protection, water filtration, provision of areas for fish and
shrimp breeding, provision of building material and medicinal ingredients as
well as also attraction of tourists.
2.1.1 1st and important things is determination of decrease
in mangrove forest area and cover.
2.1.2 Determine the reasons of the degradation of mangrove
forests and quantification of areas destroyed by various factors specially.
2.1.3 Reducing freshwater & silt flows from Indus river.
2.1.4 Coverage of the mangroves forest along with the coastal
area of Pakistan.
2.1.5 Mangrove forests or trees are essential part of inter
tidal zone of the coastal area environment
2.1.6 Changes occurring in the Indus delta due to
transgression of Arabian Sea.
2.2 Area of Study
LANDSAT imageries of different years about 1990, 2000, 2010 and 2016-17 current
images download from USGS Earth explorer website
that is a free site for different satellite’s data. Using Erdas Imagine
software for Image Pre-processing, Mosaicking, Classification, and Accuracy Assessment for detection of
Mangroves in the Map.
is necessary to monitor and identify mangroves and its types and spatial extent
near coastal areas because it plays an important role in coastal ecosystem and
environmental protection. Mangroves are one of the most important objects for
maintaining coastal ecosystem and environment. It provides a natural barrier
and helps to prevent shoreline erosion, shielding inland areas from severe
damage during hurricanes and tidal waves.
2.3.1 Identify the changes in the extent using historic
remotely sensed datasets.
2.3.2 In Pakistan, satellite data has been significantly
used for the quantification and management of mangroves forest.
2.3.3 Determination of decrease in the mangrove forest area
Methodology is adopted for
following main steps.
3.1.1 Pre-processing of data including atmospheric
and geometric corrections.
3.1.2 Image classification using supervise
3.1.3 Accuracy assessment
3.1.4 Change detection analysis of mangroves.
3.2 Satellite Data
this method we used the LANDSAT imageries of different years about 1990, 2000,
2010 and 2017 current images
download from USGS Earth explorer website that is a free site for different
satellite’s data. Using Erdas Imagine software for Image Pre-processing,
Mosaicking, Classification, and
Accuracy Assessment for detection of Mangroves in the Map.
5 imagery 1990
5 imagery 2000
5 imagery 2010
8 imagery 2017
3.3.1 ERDAS Imagine 2014 is used for the satellite image processing then its
3.3.2 Arc Map is used for making final Maps of that particular
3.3.3 MS Office is used for report writing, Presentation and graphs
3.4 Data Preparation/collection
imageries in 1990, 2000, 2010 and 2017 were collected from USGS website also
the Image acquisition date is important because vegetation and crops reflect
differently at the beginning and the end of the rainy season due to phonological
and temperatures disparities, and their reflectance varies from the dry season
to the rainy season.