Mapping of Landuse/Landcover Changes of Chennai Coast and Issues related to Coastal Environment Using Remote Sensing and GIS
Author(s) – Santhiya.G, Lakshumanan.C, Muthukumar.S
Coastal areas are very valuable in view of human beings and more dynamics for land use due to urbanization and industrialization. It is essential to assess the land use/land cover changes for coastal zone management, technologies like Remote sensing and GIS were used to monitor the coastal land use dynamics for the Chennai coast covers stretch of approximately 125kms from Pulicat Lake (North) to Kovalam creek (South). Survey of India Toposheet, Land sat and IRS-LISS III satellite data were used for the years 1976, 1999 and 2007. The maps were compared and changes were attributed; and show that the drastic changes in land use profile. Vegetation cover decreased from 15.49% to 11.19% during 1999-2007 & 19.49% to 15.77% (1976-1999) respectively. Due to the increased population the settlement and built up areas increased considerably 16.82% (1976), 26.20% (1999) and 31.91% (2007). Field observation shows the current status and issues of coastal environmental problems. Study suggested some remedial measures to protect the coastal environment
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Study on Hyperspectral Signatures for Magnetite Iron ore in Thattayengerpet region of Trichirappalli district in Tamil Nadu State, India.
Author(s)– Raja.S, Rajendran.S, Poovalinga Ganesh.B, Thirunavukkarasu.A
Reflectance spectroscopy of natural surfaces is sensitive to specific chemical bonds in materials, whether solid, liquid or gas. Spectroscopy has the advantage of being sensitive to both crystalline and amorphous materials, unlike some diagnostic methods, like X-ray diffraction. The advantage of spectroscopy is that it is too sensitive to small changes in the chemistry and/or structure of a material. Variations in material composition often cause shifts in the position and shape of absorption bands in the spectrum. Spectroscopy brings also the advantage of allowing us to obtain more details about the chemistry of our natural environment based on the reflectance characteristics. In the present work Study on Hyperspectral Signatures for Magnetite Iron ore exposed in the Thattayangerpet area of Trichirappalli district in Tamil Nadu State, India have been undertaken. Geologically this litho unit belongs to the high grade polymetamorphic terrain of the Southern peninsular shield. Hyperspectral signature were collected in the laboratory from Magnetite Iron ore samples using ASD Spectroradiometer operating in visible and infrared (325 to 2500 nm) region. The analysis of the spectral profiles was conducted using the ASD View spec software and the output in the form of spectral reflectance averages and graphs was exported in an ascii format for further analysis. The exported data was then imported to Environment for Visualizing Images (ENVI) software and used as using endmember spectra plot for detailed analysis and interpretation. The average of seven spectral profiles and compared with the spectral library like this USGS, JPL, and JHU. The result of analysis for Magnetite Iron ore is best matched between laboratory hyperspectral signature and laboratory hyperspectral signature and their absorption peak 0.9-1.0µm.
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Estimation of above ground biomass in Indian tropical forested area using multi-frequency DLR-ESAR data
Author(s) – Vyjayanthi Nizalapur, Chandra Sekhar Jha and Rangaswamy Madugundu
This paper presents experimental results obtained with DLR-ESAR airborne data in C, L and P-bands over the parts of Gujarat, India. The aim is to estimate the above ground biomass and quantify various levels of above ground forest biomass with the help of empirical relationship of the backscattering coefficients and ground inventory. Extensive field data were collected to characterize forest vegetation parameters in the plots. Ground inventory data viz., GBH, tree height was collected. Plot level above ground tree biomass (AGB) is estimated from the collected ground data using the existing allometric equations at stand level in the study area. Regression analysis is carried out between above ground biomass and backscatter coefficient of C, L and P- bands in VV polarization. The obtained regression equation was used to estimate the above ground biomass from ESAR data in C, L and P- bands. Results showed that with increase in the biomass levels, backscattering coefficient also increases and C-band ESAR data is capable of predicting biomass up to 70 Mg/ha, L-band upto 150 Mg/ha and P-band upto 200 Mg/ha. Comparison of the estimated above ground biomass of airborne microwave DLR-ESAR data in C, L and P-bands was also carried out.
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Remote Sensing and GIS Applications on Change Detection Study in Coastal Zone Using Multi Temporal Satellite Data
Author(s) – Prabaharan.S,Srinivasa Raju.K, Lakshumanan.C,Ramalingam.M.
Coastal zones are most vulnerable for land use changes in this rapid industrialization and urbanization epoch. It is necessary to evaluate land use – land cover changes to develop efficient management strategies. The main Information on landuse/landcover in the form of maps and statistical data is very vital for spatial planning, management and utilization of land. In the study, remote sensing and geographic information system (GIS) were used in order to study landuse/landcover changes. Land use changes may influence many natural phenomena and ecological processes, including runoff, soil erosion and sedimentation and soil conditions. The urban areas are changing due to various human activities, natural conditions and development activities. According to the user’s requirements, updating of landuse mapping is required to various departments. The aims of this study it has been observed that the important coastal land use types of Vedaranniyam coast (Creeks, Rivers) have been reduced drastically in their extent due to reclamation, dredging, tipping and other anthropogenic activities along the coastal zone.
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