eChapters

Data pre-processing is a crucial step in data analysis and machine learning that involves preparing raw data for further processing and analysis. Proper preprocessing helps in improving the quality of the data, which in turn enhances the performance of machine learning models. Smoothening VIS-NIR spectra enhances signal quality by reducing noise, crucial for better spectral data interpretation. Key methods include Savitzky-Golay and moving average filters, wavelet transform (WT), and frational derivatives.
Savitzky-Golay Filter: The Savitzky-Golay filter is widely used for smoothing spectral data. It preserves the original shape and features of the signal better than simple averaging filters.Savitzky-Golay Filter fits low-degree polynomials to successive subsets of data points using linear least squares, effectively preserving the signal’s original shape and features, making it ideal for spectroscopy. Moving Average:Moving Average is a simple method that reduces random noise by averaging neighboring data points. While effective, it can sometimes blur sharp features.
Wavelet Transform: Wavelet transform is effective for denoising spectral data, especially when dealing with non-stationary signals.Wavelet Transform (WT) decomposes spectral data into multiple scales, providing both time and frequency information. It is particularly useful for identifying features like peaks and trends. WT includes Continuous Wavelet Transform (CWT), Discrete Wavelet Transform (DWT), and Maximal Overlap Discrete Wavelet Transform (MODWT). Fourier Transform Filtering: Fourier transform can be used to remove highfrequency noise components from the spectra.
Median Filter: Median filtering is useful for removing outliers and preserving edges in the spectral data.
Fractional derivative:Fractional derivative generalizes traditional derivatives to non-integer (fractional) orders, allowing for arbitrary order derivatives. This provides a flexible, nuanced approach to modeling and analyzing complex, nonlinear, or memory-dependent behaviors.

Introduction

Soil is one of the vital resource, and is the basis of the existence of mankind. Management of this resource including its conservation and utilization is of crucial importance. It is a base on which all life depends. In the recent past, with burgeoning populations and the national goals of seeking self-sufficiency in food and fibre production, this resource base is slowly being stripped. While natural systems often adapt to stress in a remarkable fashion, some relationships - once destroyed - can never be restored. Soil resources can be assessed and monitored through its spectral signatures gathered through remote sensing.

The term ‘remote sensing’ is commonly restricted to methods that employ electromagnetic energy (such as lights, heat, micro wave) as means of detecting and measuring target characteristics. Sensors acquire data as various earth surface features reflect or e mit electromagnetic energy (EM energy). Remote sensing is the technology that is now the principal method (tool) by which the earth’s surface and atmosphere (as targets or objects of surveillance) are being observed, measured, and interpreted from vantage points. Remote sensing of the earth traditionally has used reflected energy in the visible and infrared, and emitted energy in the thermal infrared and microwave regions to gather radiation that can be analyzed numerically or used to generate images whose tonal variations represent different intensities of photons associated with a range of wavelengths that are received at the sensor.

Split-plot design is particularly useful when certain biological treatments cannot conveniently be applied to small experimental units. This chapter explains how large experimental plots can be divided into smaller sub-plots to accommodate subsidiary treatments. Main-plot treatments are randomly allocated to larger units, while sub-plot treatments are independently allocated within them. The design allows researchers to study main effects, sub-plot effects, and interactions, although greater precision is generally obtained for sub-plot comparisons than for main-plot comparisons. Examples include wood preservation and nursery experiments involving sowing methods and seasons. The chapter also explains the two error terms required for appropriate analysis of split-plot experiments.

Application of the principal of geomorphology provides information, which will be of value in predicating the geometry of aquifers. On weathering and erosion, many geological formations develop landforms that are distinctive in respect of slope continuity of outcrops and symmetry of valley flanks. The surface topographic features of bedrocks can some times be extrapolated to reasonable depths to predict the thickness of alluvium or aeolian sands occurring as valley fill deposits, by treating slope profile as mathematical curves for which equations similar to regression equations can be found (Doornkamp and King, 1971).

The influence of tectonic movements and resultant structural features on landform is of paramount importance for hydrogeomorphologists. The control of structure on landforms and hydrogeological processes are being discussed here. The structural geology concerns with the features such as uniclinal or inclined beds, folds, faults and joints. Of these the structural features like faults, fractures, joints etc appear as linear feature.

Linear features on the surface of the earth have attracted the attention of geologists for over one hundred years. This interest has grown most rapidly since the introduction of aerial photographs into geological studies. Geologists have recently proven that various structural features perceived in remotely sensed images are reliable indicators of geologic resources (Caran et al, 1982). These structures have been used in many applications: petroleum and mineral exploration (Blanchet, 1957); nuclear energy facility siting (Seay, 1979); geothermal assessments (Woodruff et al, 1982); and water resource investigations (Lattman and Parizek, 1964). Lattman and Parizek (1964) established a relationship between the occurrence of groundwater and fracture traces for carbonate aquifers, and in particular zones of localized weathering and increased permeability and porosity underlying these structures.

Abstract

Groundwater is one of the major sources of exploitation in arid and semi -arid regions of Rajasthan. To protect groundwater, its data on spatial distribution are important along with quantity. Analysis of quality of groundwater is also very important, because the physical and chemical characteristics of groundwater determine its suitability for agricultural, industrial and domestic usages. The importance ground water increases many fold for arid tracts like Western Rajasthan. Here quality of water is also matter of serious concern. Geostatistics methods are most advanced techniques for interpolation of Groundwater quality. The present study appraises the groundwater quality of western Rajasthan for agricultural purpose with GIS technology. Kriging Raster Interpolation technique of spatial analyst module in Arc GIS software has been used to generate the spatial distribution map of ground water for agricultural purpose. In western Rajasthan only 28% (58109 km2) of ground water falls under the category of good and is suitable for agricultural use. 

Abstract

Conventional wisdom holds that variability in rainfall represents a significant variability of agriculture production. But urbanization of the cities on one hand and climate change on theother hand areaffecting the agriculture. Surprisingly, there have been very few analyses exploring the link between rainfall variability and urbanization on agriculture production. Therefore an attempt is made in this paper to know the affect of rainfall variability and urbanisation on the cropping area. For this purposeNDVI analysis is carried out in the catchments of Osmansagar and Himayathsagar Reservoirs by using the medium to high spatial resolution multi spectral data provided by remote sensing satellites, such as Landsat TM, IRS-1C/1D LISS-III and IRS-P6 LISS-III has been used for the years1989, 1994, 1998, 2002 and 2008 for Kharif season, 1975, 1990, 1994, 1998, 2003 and 2008 for rabi season which is collected from NRSC (National Remote Sensing Centre). From this analysis it is found that the increment is more in rabi season compared to kharif season due to the increment of non-monsoon rainfall intensities and ground water withdrawal structures. The increased utilization of the groundwater is causing the reduction of inflows to the reservoirs in the recent years because whatever the rainfall that occurs in the catchment, first utilised for meeting the depleted soil moisture and ground water consequently reducing the surface runoff.

Keywords : Climate change, Urbanisation, Inflows, Cropping area, NDVI

Raster sub-setting is done to select the desired area or bands of the raster image on which the user wants to perform analysis. Raster sub-setting is done in two ways:

Spectral subset: Spectral sub-setting is done to extract few desired bands from the multiband raster image which are required for analysis.

Spatial subset: Spatial sub-setting is done to minimize the area or extent of raster image to the desired area or extent for further analysis.

Raster sub-setting in R is done by functions available in the ‘raster’ package. The following packages are required in this chapter:

Supervised classification is the technique to classify raster image in which prior information about the classes in the form of training sites is provided by the user. Training site represents a homogeneous area in a particular class. The spectral response pattern of training sites is used to classify the raster image.The pixels of raster imagewhich have spectral response pattern similar to that of training sites of a particular class are grouped in that class. As there is some variability in the spectral response pattern of a particular class, therefore, multiple training sites per class are taken for supervised classification. Supervised classification of raster images can be performed by various methods. Conventional methods include maximum likelihood classifier, minimum distance to mean classifier, and parallelepiped classifier. Now a days, machine learning algorithms are also gaining importance in this context. These classifying algorithms are first trained or calibrated using the data of training sites.This trained model is then validated on the independent datasets for accuracy assessment. If the accuracy of the developed model is of acceptable level, then that model is used for the classification of raster data.

In this chapter, we are going to discuss the execution of maximum likelihood classifier and few machine learning techniques for supervised classification of raster image in R software. The training sites used in this exercise are in the form of points shapefile. The raster image is classified into six classesi.e. built- up, fallow soil, riverine sand, salt-affected soil, vegetation, and water. For performing this exercise, first of all,set the working directory and import the required packages.

Abstract

The state of Tamil Nadu has a low easterly gradient slope and there are number of rivers, big and small originate from the west flow towards east south easterly and confluence the Bay of Bengal. These were grouped into seventeen major and minor river basins, the Cauvery being the largest basin and the river is also a near perennial river. These river basins receive rainfall both from the southwest and northeast monsoons. The state has over 40,000 surface water bodies and number of major dams and reservoirs. Even then, since the rainfall of the north east monsoon, the major source of water source to these basins, occurs in short span of few days with high rainfall, neither adequate storage is there to store them nor the recharge possibility is available, thus all leading to flooding and wastage. The 40,000 and odd water bodies are heavily silted and polluted too. The paper provides an over view of all these, basin wise, and in addition, strongly advocates intra state river linkage and improvised irrigation management as the best option to save the state from its water deficiency.

The President of India, in her address to both Houses of Parliament on 4 June 2009 announced:
 
My Government proposes to enact a new law — the National Food Security Act — that will provide a statutory basis for a framework which assures food security for all. Every family below the poverty line in rural as well as urban areas will be entitled, by law, to 25 kilograms of rice or wheat per month at Rs. 3 per kilogram. This legislation will also be used to bring about broader systemic reform in the public distribution system.

Since then, various arms of government as well as civil society organisations have been working on methods of redeeming this pledge.  The National Advisory Council (NAC) headed by Sonia Gandhi has recently provided a broad framework for achieving the goal of food for all and forever.  The suggestions of NAC include the initiation as soon as possible of special programmes all over the country to insulate from hunger and malnutrition pregnant and nursing mothers, 0-3-years-old infants, street children, destitutes, old and infirm persons, patients suffering from HIV/AIDS, tuberculosis and leprosy, physically or mentally handicapped persons and other disadvantaged citizens.

Abstract
 
India shares 16% of the world population, while its land is only 2% of the total geographical area of the world. Naturally, the pressure on the land is often beyond its carrying capacity. Therefore, the productive lands, especially the farmlands in the India are in the constant process of various degrees of degradation and are fast turning into wastelands. At present, approximately 68.35 million hectare area of the land is lying as wastelands in India. Out of these lands, approximately 50% lands are such non-forest lands, which can be made fertile again if treated properly. It was unprotected non-forestlands, which suffered the maximum degradation mainly due to the tremendous biotic pressure on it. In the last 50 years it is India's lush green village forests and woodlots have been deforested to the maximum. 

Abstract

Tsunami (2004), that struck the Tamil Nadu coast has left deep marks in the minds of the affected society. The interview conducted in the coastal villages of the tsunami affected Nagapattinam has brought out many salient societal issues like, loss of leadership, widow hood, debt grip, psychological depression etc, which warrant deeper look to bring them out from the syndrome.

Keywords: Tsunami (2004), Social issues, Nagapattinam, India

INTRODUCTION

The damages caused by tsunami (2004) along the coastlines of most of the South Asian countries are indelible not only from the minds of the coastal population but also from the heart of the entire humanity. The worst affected in the disaster are the fishing community. Many of their mechanized and un-mechanized boats and catamarans were converted to useless debris and garbages by the heartless tsunami. When their settlements themselves were swallowed even with out chewing, nothing to talk about their fishing nets which were just blown off by the ferocious tsunami. In addition, the infrastructure facilities like roads, communication systems, water and power supply were also incalculably damaged. Next to fishermen community, the affected souls were the farmers whose cultivable lands were turned into marine wet lands with swimming and tossing fishes. The Indian subcontinent was facing such onslaughts of various natural disasters periodically but our morale always stood by our side prohibiting us declaring them as national calamities for getting international aids. Specifically in this case, the central and state governments, NGOs and Voluntary Organizations have risen phenomenally to help the affected who were in need. Despite best efforts taken to provide relief and rehabilitation to the affected people, the tsunami has seedled some societal issues / syndrome, which may take long years to settle; it may not settle too. The paper discusses some of such issues gulled out through the interview conducted amongst various cross sections of the affected community.

Introduction 
A system approach to understand the soil-plant-water continuum fundamentally shifts our perspective from viewing these elements in isolation to recognizing them as an intricately woven, dynamic whole. It’s about appreciating that every change in one part of this natural tapestry—be it the soil, the plant, or the water itself—reverberates through the others, creating a cascade of interconnected effects. This holistic lens allows us to dissect the continuous exchange of water and energy, unraveling the complex feedback loops and emergent behaviors that characterize this vital agricultural system. Instead of merely tracking individual inputs and outputs, a systems view compels us to comprehend how these components influence each other over time, leading to a far more nuanced understanding of their collective behavior. At the heart of this continuum lie three primary, yet inseparable, components: the soil, the plant, and the water itself, all profoundly influenced by the atmosphere. The soil acts as both a foundational anchor and a dynamic reservoir. Its very composition—the proportion of sand, silt, and clay, its structure, and its organic matter content—dictates how readily water infiltrates, how much it can hold against the pull of gravity, and how quickly it can release water to plant roots. Processes like infiltration, percolation, and capillary rise describe water’s journey within the soil matrix, while evaporation from the soil surface represents a significant loss pathway. Crucially, the soil also serves as the medium for nutrient availability, with water acting as the solvent that transports these vital elements to the roots. The plant, in turn, is the primary biological conduit for water’s journey from the soil back to the atmosphere. It actively absorbs water through its roots, moving it upward through the xylem to the leaves, where it is transpired through tiny pores called stomata. This transpiration process is not merely a loss; it’s the driving force behind the plant’s physiological engine, facilitating

New techniques and approaches to groundwater studies are always in deep concern with the hydrogeomorphologists. The designing of new techniques or adapting existing techniques with better enhancement to solve practical problems in the study of groundwater are of central concern. One of the recent technical developments include the mathematical model of groundwater flow that has become the most widely used computer-based model in the groundwater industry. Techniques to identify and date recently recharged water that is useful in characterizing the susceptibility of hydrogeologic environments to contamination are utilized by various research groups all over the world.

Geophysical methods for determining the hydraulic properties of fractured rocks gained the importance in the hydrogeomorphic studies. Predicting the movement of water and contaminants through fractured rocks has been one of the most challenging problems in hydrogeomorphology. Besides conventional and above mentioned techniques the techniques discussed in this chapter are Remote Sensing, Geographical Informational system (GIS), Global Positioning System (GPS), Digital Elevation Model (DEM), Groundwater Information System (GWIS), Digital Surface Terrain Modelling (DSTM), Multicriteria evaluation (MCE) and Thermal Infra Red (TIR) Mapping and Microwave Data.

Abstract

The tectonic and the geomorphic features observed along the west coast of the area between Mangalore and Cape Comorin show that the NNW-SSE trending west coast has been carved out by the Western Ghats orogeny and the related NNW-SSE trending release fractures. The sinuosity of the otherwise straight coast line is due to Quaternary cymatogenic arching caused by the thrust related to the northerly movement of the Indian plate. The coast line has further attained peaks, projections and serrations due to the ENE-WSW trending series of Precambrian extension fractures which were reactivated gaining the northeasterly directed forces from the rising Carlsberg ridge. Overall, the west coast is being tectonically evolved even today due to the rise of Carlsberg ridge and the Indian plate movement.

Abstract

The analysis of IRS - 1A satellite imagery has indicated the existence of two NE - SW trending sub parallel faults along which the coast is undergoing land subsidence as revealed by the concavity in the shore line, preferential migration of the river systems and the drainage congestion, absence of beach ridges, occurrence of off shore shoal etc. The study has further indicated chains of tectonically induced environmental problems such as ground water logging, coastal zone flooding, storm surges, harbour sedimentation etc.

Abstract

The present study has revealed that the NE-SW and WNW-ESE trending sinistral faults are very active along the Tamil Nadu coast and the same have caused considerable slope modifications along the Coleroon and Karungalar rivers which are well-manifested in the land, water and mudflat distribution pattern. Similarly, the progradation of the land in Vedaranniam nose is due to the rise of Pattukottai-Mannargudi area and the time transgressive modifications of the Vedaranniam backwater indicates the opening up of the N-S trending Pleistocene-Holocene faults.

Abstract

Satellite photographs depict exciting evidence on the migratory melodrama of river systems. A study has been conduced in parts of Tamil Nadu using IRS-IA Satellite pictures, archaeology and Tamil literature, which reveals that from Pleistocene to 2700 years B.P.(Before Present) the river Cauvery flowed in a northeasterly direction from the Stanley reservoir via Chinnar, Palakkodu, Mattur, Tiruppathur (Tiruppattur), Gudiyatham (Gudiyattam), Vellore and Walajapet to meet the sea at Madras. From 2700 to 2300 years B.P., it flowed via Uttangarai and Tirukkovilur to meet the bay of Bengal near Pondicherry, over which the present-day Ponnaiyar is a misfit stream . From 2300 to 1300 year B.P. it has flowed via Erode, Tirukkampuliyur, Alagarai , Tiruchy, Kiranur and Pudukkottai meeting the sea in the region where the present-day Agniar and Ambuliar meet the sea. Subsequently, between 1600 and 1300 years B.P., the Cauvery flowed along the present-day tracts of the Vennar and Vettar, after which it seems to have flowed as the Kodamurutti, Arasalar and PalanCauvery from 1300 to 1000 years B.P. From about 900 years B.P. it flowed via Tirupurampayam (Tirupurambiyam), Achalpuram till around 750 years B.P. and then it is stabilised as the Colleroon (Kollidam). Such periods and phases of river migration as well as their implications in the search for archaeological remains are discussed in this paper.

Abstract

There are two distinct types of oscillations in global oceans, separated in their frequencies by the period of the pendulum day. One species is the gravity waves and the other is the rotational waves, associated with earth’s rotation. Both these species can be found in tidal records around islands as well as near coastlines. These two types of modes are usually found in the tsunami records on tide gauges. The tide gauge records as well as visual descriptions of the water levels during and after the occurrence of a tsunami clearly show the presence of these oscillations. During the tsunami of 26th December 2004 in the Indian Ocean, media reports suggested high water levels persisted around the Andaman and Nicobar Islands for several days. These persistent high water levels can be explained by invoking the existence of trapped and partially leaky modes on the shelves surrounding these islands.

Keywords: Oscillations in global waves, Tsunami (2004), Andaman and Nicobar islands.

Abstract

Though people belonging to different disciplines from the common citizen to top level administrators are familiar with cyclones, floods, earthquakes, landslides, droughts, etc., the tsunami which struck and devastated over 1000 km long Tamil Nadu coast was not only unexpected but also an unknown phenomenon for the people of this part of the region. The Government of Tamil Nadu, though faced with this disaster for the first time, has efficiently managed the crisis owing to clear policy directions from the top political executive of the government, the planned working of the ministers, the committed service rendered by the senior officials and the tireless efforts of district collectors and their supporting staff down the line. The immediate measures taken in search, rescue and relief operations are detailed in this paper. Also covered are the rehabilitation measures undertaken including those for orphaned children and unmarried girls and the steps adopted for the prevention of epidemics.

Keywords: Tsunami Disaster, State Administration, Relief and Rehabilitation, Tamil Nadu.

INTRODUCTION

India is traditionally vulnerable to natural disasters on account of its geo-climatic conditions. Floods, droughts, cyclones, earthquakes and landslides have been occurring regularly in some part of the country or the other. In Tamil Nadu, the unprecedented drought in 2002-03, followed by another drought of comparatively less severity in 2003-04 and the floods in the northern coastal districts in October-November, 2004 had kept the State machinery on constant alert. But the tsunami that struck the coastal districts on 26^th December, 2004 was an altogether new and nightmarish experience. It was a disaster, the like of which, had not been seen before. The suddenness and the ferocity with which the waves gushed into the habitations along the 1076 km long coast line, taking the people totally unaware, caused unprecedented damage, death and destruction and posed the greatest challenge to the State administration. However, the state faced the challenge successfully, thanks to the vision and commitment shown by the Government and the timely help rendered by a number of non-governmental organisations and groups.