Recent Articles-IJGGS

A study on Tamilnadu coastal deformation processes using SAR Interferometric data

Author(s)– German Amali Jecintha .T1, V.E. NethajiMariappan2

ABSTRACT

SAR systems take advantage of the long-range propagation characteristics of radar signal and the complex information processing capability of modern digital electronics to provide high resolution imagery. The paper focuses on the differential interferometric SAR (Synthetic Aperture Radar) technique for the monitoring of terrain surface deformations. A series of ERS (Earth Resources Satellite) 1&2 and ASAR (Advance Synthetic Aperture Radar) images acquired at different dates before and after tsunami were used in this study. Two SAR images are combined to produce a SAR Interferogram to reveal information about the third dimension (elevation) of the object and to measure small displacements of objects between the two image acquisitions. Interferometric processing, the SLC images were accurately co registered and the complex interferograms are formed by multiplying each complex pixel of the first image by the complex conjugate of the same pixel in the second image. Coherence images and interferograms were then derived from pairs of co- registered SLC images. The interferogram thus generated is a complex image itself. A careful observation of the images reveals that closer are the fringes, more are the topographical changes or height variations which represents the main observation for the estimation of the coastal deformations processes.

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Recent Articles-IJGGS

Geo-Spatial Yield Monitoring Technology for Mechanized Almond harvest

Author(s)– Balaji Sethuramasamyraja, Sunny Sehgal, Jim Yager

ABSTRACT
Yield monitoring is critical for almond growers to garner profitability through application of geospatial technology and site specific crop management in almond production. Almond growers could optimize water and application of inputs based on soil thematic layer of the field that has a strong correlation to yield besides management practices. In this research a commercially deployable yield monitor was developed for almonds with sensing, global positioning system (GPS) and geographic information systems (GIS) technology (Digi-Star® Yield Monitor). Yield maps were developed for production almond fields. The yield data was validated using sampling datasets which were in turn correlated to soil thematic layer developed using soil electrical conductivity (Veris® 3100 EC Mapper). The sampling from multiple soil zones representing a soil texture were correlated to the almond turn out ratio. Also, the effect of navel orange worm (NOW) on almond meat turn out ratio was reported.

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Recent Articles-IJGGS

Integration of Remote Sensing data and GIS for prediction of land cover map

Author(s)– Samereh Falahatka et.al.,

ABSTRACT
Satellite remote sensing and geographic information system (GIS) have been widely applied in identifying and analyzing land use and land cover change. In this study, aerial photos and MSS, TM and ETM+ images of Isfahan and its environs were used to provide maps of land cover for 1955, 1972, 1990 and 2001. A hybrid method was used for image classification: a combination of supervised and unsupervised classification. Cellular automata filter facilities and Markov model were used together in a CA-Markov model for predicting land cover maps. To study the accuracy of the predicted maps and validation of the CA-Markov model, three methods were used: a calculating agreement and disagreement table, a chi-squared goodness-of-fit test and an error matrix. The results indicate that if land cover change processes are constant, the CA Markov model predicts land cover changes for the following years, for which agreement between predicted maps with actual map is less than 70% in this study area.

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