2. Mangrovestudy 2.1 Study objectives:-Specific objectives of this study are following:Primeintent of this study is the detection of area covered by mangroves especiallyin Karachi area, adumbrate the existential threats being faced by mangroves,comparison of past and present mangrove covered areas, and suggestions fortheir betterment in future.
Theyprovide various ecological and economical ecosystem services contributing tocoastal erosion protection, water filtration, provision of areas for fish andshrimp breeding, provision of building material and medicinal ingredients aswell as also attraction of tourists.2.1.1 1st and important things is determination of decreasein mangrove forest area and cover.2.1.
2 Determine the reasons of the degradation of mangroveforests 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 coastalarea of Pakistan.
2.1.5 Mangrove forests or trees are essential part of intertidal zone of the coastal area environment2.1.
6 Changes occurring in the Indus delta due totransgression of Arabian Sea.2.2 Area of StudyUsed theLANDSAT imageries of different years about 1990, 2000, 2010 and 2016-17 currentimages download from USGS Earth explorer websitethat is a free site for different satellite’s data. Using Erdas Imaginesoftware for Image Pre-processing, Mosaicking, Classification, and Accuracy Assessment for detection ofMangroves in the Map.
2.3 Importanceof study:Itis necessary to monitor and identify mangroves and its types and spatial extentnear coastal areas because it plays an important role in coastal ecosystem andenvironmental protection. Mangroves are one of the most important objects formaintaining coastal ecosystem and environment. It provides a natural barrierand helps to prevent shoreline erosion, shielding inland areas from severedamage during hurricanes and tidal waves.
2.3.1 Identify the changes in the extent using historicremotely sensed datasets.2.3.
2 In Pakistan, satellite data has been significantlyused for the quantification and management of mangroves forest.2.3.3 Determination of decrease in the mangrove forest areaand cover.
3. METHODOLOGY/DATASETS:3.1 MethodologyMethodology is adopted forfollowing main steps.
3.1.1 Pre-processing of data including atmosphericand geometric corrections.3.
1.2 Image classification using superviseclassification3.1.3 Accuracy assessment 3.1.
4 Change detection analysis of mangroves.3.2 Satellite DataInthis method we used the LANDSAT imageries of different years about 1990, 2000,2010 and 2017 current imagesdownload from USGS Earth explorer website that is a free site for differentsatellite’s data. Using Erdas Imagine software for Image Pre-processing,Mosaicking, Classification, and Accuracy Assessment for detection of Mangroves in the Map.3.2.1 LANDSAT5 imagery 1990 3.2.2 LANDSAT5 imagery 2000 3.2.3 LANDSAT5 imagery 2010 3.2.4 LANDSAT8 imagery 20173.3 Software Used 3.3.1 ERDAS Imagine 2014 is used for the satellite image processing then itsclassification 3.3.2 Arc Map is used for making final Maps of that particulararea.3.3.3 MS Office is used for report writing, Presentation and graphs 3.4 Data Preparation/collectionLandsatimageries in 1990, 2000, 2010 and 2017 were collected from USGS website alsothe Image acquisition date is important because vegetation and crops reflectdifferently at the beginning and the end of the rainy season due to phonologicaland temperatures disparities, and their reflectance varies from the dry seasonto the rainy season.