OSGeo Events, FOSS4G 2008

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Juwairia Mahboob

Building: Cape Town International Convention Centre
Room: Kgalagadi Room (Room 2.4b)
Date: 2008-09-30 03:30 PM – 05:00 PM
Last modified: 2008-09-08


Forests are a key element of environment. The conservation and management of these forests is vital for maintaining environmental stability and ecological biodiversity. The management of forests especially in response to human activities, such as tourism and livestock grazing, require information on quality and quantity of vegetation. Forest inventories have traditionally been used for acquiring quantitative and qualitative information of forests in Pakistan. The parameters that are collected and measured in the forest include species type, age, height, crown diameter, volume etc. With the advent of technology, remote sensing has been found to provide an alternative for forest mapping and monitoring at less time and low cost. This research poses to study two of the parameters, i.e. type of species and crown closure with Quickbird & Hyperion imageries of Ayubia National Park. Crown closure is the percentage or proportion of ground area covered by the vertical projection of tree crowns. Crown closure is a bio-physical parameter important for quantifying the energy and mass exchange characteristics of terrestrial ecosystems such as photosynthesis, respiration, transpiration and rainfall interception. It is an important variable in the estimation of stand volume and in evaluating silvicultural operations and ecological conditions. It has a significant influence on snow pack accumulation and snow melt. Spectral reflectance of plant species vary with wavelength to different degrees. Spectral difference among plant species, have been found by visually looking at the shape of vegetation spectra. Multispectral sensors may not be effective in distinguishing small spectral differences of canopies. On the other hand, hyperspectral imagery having high spectral resolution is expected to give better results. But, the spatial resolution of space-borne hyperspectral imagery is low for analyzing individual tree species. Hence, this study will employ both multispectral and hyperspectral imageries for classification of forest tree species. Crown closure will be assessed by employing feature extraction methods such as Wavelet Transform Method, Band Selection Method and Principal Component Analysis. Whereas, species classification will be carried out with object oriented classification techniques such as Nearest Neighbour Classification, Decision Tree Algorithm and Support Vector Machine Algorithm. A DEM will be generated based on 1:50,000 scale topographical sheet. The contours will be digitized at an interval of 20 meters. Moreover, aspect & slope will be derived from DEM. The field data will be collected by visiting sites in the field, measuring several parameters (crown closure etc.) and determining coordinates with GPS. 10 sample plots will be taken for a sampling intensity of about 30%. Ayubia National Park will be selected as the study area for this research as the National Park has a diverse variety of coniferous and broadleaved tree species in their natural environment. The primary objective of a national park is to protect the landscape, flora and fauna in its natural state and to which the public is allowed access for the purpose of recreation, education and research. Hunting, shooting, trapping, killing or capturing any wild animal within a 3 miles radius of the boundaries of the park and felling of trees and clearing any land in the park is prohibited. Managers require an understanding of the spatial distribution of species composition and crown closure to manage forest resources for particular uses such as recreation, wildlife production, forestry and watershed management. This study will help assist forest managers in the management of forests and will open up new avenues for research in the field of forest inventory and remote sensing in Pakistan.