Landslides are an endemic problem in India. Indiscriminate deforestation coupled with unusually heavy rains and geological setting of certain areas make some parts of India landslide hazard prone. The Department of Science and Technology has taken an initiative to promote research on landslides. Landslide Research gives a detailed overview of the studies under this initiative. The studies are covered under the headings of Earth System Processes and Landslides, Landslide Hazard Zonation Mapping, LHZ Mapping and Geotechnical Investigations, Instrumentation, Monitoring and Forewarning, Satellite Based Landslide Monitoring, and Site Specific Landslide Investigations.
Each of the headings contains papers covering the topic through case studies of specific areas. Very good use has been made of GPS data, remote sensing imagery, including DEMs and GIS as well as traditional geological, geomorphic, geo-statistical and geotechnical techniques. It is also interesting to see at least one study using Interferometric SAR data. The ground based instrumentation for landslide detection has been covered in detail. Each paper is profusely illustrated with color plates and diagrams, which greatly helps in understanding the analysis, results, and conclusions. The methodologies are explained with flow charts.
The remotely-sensed data analysis seems to have an analogue visual rather than a digital. The GIS usage also is limited to overlay analysis. The integration of datasets with ground data and the combined analysis is muffing. A section on landslide prevention would have been useful. This has been covered as parts of papers under the head mitigation; however a separate section would have been useful, particularly for anthropogenic disturbance control. For example, the consequences of indiscriminate building activities in hill stations like Nainital could have been addressed. Focus on indexing would also have helped the readers to do a keyword search.
DST has to be lauded for initiating and funding these studies and bringing out the results in book form. The case studies should be very useful to researchers in the future. It is hoped that DST continues these studies addressing some of the aspects outlined above.
S. M. Ramasamy and Bhoop Singh
New India Publishing