eChapters

Abstract

A study on colloids in groundwater and its relationship with the geochemical parameters is reasonably essential because of its facilitating nature to transport radionuclides in groundwater. Colloid sampling has been carried out in the coastal aquifers of southeast coast of India. Two different bore wells were selected based on the distance from the coast to collect groundwater samples. On the basis of the result achieved from this study, a reliable representation is emerging. The values of pH and EC are governed by the different size fraction of colloids. In this study, the relation between different size fractions of groundwater colloids and its pH, TDS and EC were carried out. These parameters were analyzed in the lab and its influence with four fractions of colloid like 1.2, 0.8, 0.45 and 0.22 µm have been discovered by smooth scatter plot. The accumulation of particles weighting by normal weighing instrument. There is an higher accumulation of particles found in Kalpakkam than Anupuram in all the size fractions. For separation of particles high frequency pressure was used by ultrasonic cleaner had been carried out. This method is very simple and more reasonable than any other methods.

Abstract

The development and management of fresh groundwater resources in coastal aquifers are seriously constrained by the impact of seawater intrusion. The coastal aquifers are fragile and this situation becomes more intense like that of the coastal Cuddalore region. The geochemical signature of groundwater of Cuddalore coast was studied for Pre Monsoon, Southwest, North east and Post Monsoon seasons by collecting total of 64 groundwater samples in each season. The collected samples from were analysed for physical parameters, such as electrical conductivity (EC), pH and major ion concentrations, such as Ca, Mg, Na, K, Cl, HCO₃, PO₄ and SO₄. Interpretation of analytical data shows the predominance of  Na–Cl type   in PRM and Ca- Mg-Cl type  is the dominant facies during POM. The Chaddas evaluation diagram shows that the hydrogeochemical evaluation plot for PRM samples fall in  Na-Cl type. The ratios of Na/Cl and Cl/HCO₃ is also enumerated the fact that the most of the samples from PRM and few samples from other seasons also indicates dominance of salt water intrusion.

Rainfall in India, is a phenomenon that is not just a meteorological event but the very lifeline of the subcontinent, profoundly shaping its landscapes, agriculture, and, most importantly for our study, its diverse aquatic ecosystems and the fisheries they support. India experiences a unique and dominant rainfall regime driven primarily by the monsoon, a seasonal reversal of wind patterns. The arrival, intensity, duration, and spatial distribution of this rainfall have farreaching consequences for the availability of freshwater, the health of rivers, lakes, and wetlands, and the productivity of coastal and marine environments. For aspiring fisheries professionals in India, a thorough understanding of the patterns and vagaries of Indian rainfall is indispensable.
Consider the sheer diversity of aquatic habitats across India, from the snowfed rivers of the Himalayas to the monsoonal wetlands of the Gangetic plains, the brackish backwaters of Kerala, and the vast coastline. The characteristics and productivity of each of these systems are intricately linked to the patterns of rainfall they receive. The monsoon replenishes rivers and groundwater, sustains agricultural practices that can impact water quality, influences the nutrient flow into coastal waters, and can even trigger crucial life cycle events for many aquatic species (Fig. 7.1).

Unsupervised classification is the technique of classification of raster data in which no prior information is provided by the user. Raster data is classified based on their spectral characteristics such that the pixels having similar spectral properties in the multispectral feature space are grouped together in one class. Unsupervised classification is mainly performed by clustering algorithms. The purpose of these algorithms is to minimize within cluster variability and maximize between clusters variability. The user must interpret and label the classes after performing unsupervised classification. This method of classification requires minimum data which makes it easy and quick, but user has toput efforts in identification of the classes. This method could be useful when user doesn’t have any prior knowledge about the study area. This method removes subjectivity and enables us to get the unique classes which might be unrecognized by the user. K-means is the most commonly used method for performing unsupervised classification. In this chapter, we have discussed K- means, CLARA and unsupervised random forest method for classification of raster data in R.

This book, “Meteorology and Geography” is designed to equip aspiring fisheries professionals with a foundational understanding of the atmospheric and terrestrial processes that profoundly influence aquatic ecosystems and, consequently, the distribution, abundance, and health of fish and other commercially important species. For too long, the study of fisheries has sometimes been perceived as largely focused on the biology and ecology within the water itself. While these aspects are undeniably vital, the reality is that aquatic environments are not isolated entities. They are inextricably linked to the atmosphere above and the land surrounding them. The weather patterns we experience daily – from sunshine and rainfall to storms and temperature fluctuations – directly impact the physical and chemical characteristics of our oceans, lakes, and rivers. Similarly, the geographical landscape, including topography, soil composition, and coastal features, plays a critical role in shaping these aquatic habitats. Consider for a moment the seemingly simple act of rain. Rainfall over land influences river discharge, bringing nutrients and sediments into freshwater and coastal systems. Changes in salinity, turbidity, and nutrient levels can dramatically alter the suitability of these waters for different fish species. Strong winds can drive ocean currents, upwelling events that bring nutrientrich deep waters to the surface, and the dispersal of fish larvae. Extreme weather events like cyclones and floods can cause devastating impacts on both wild and aquaculture-based fisheries. Furthermore, the broader geographical context dictates the regional climate, influencing long-term patterns of water temperature, precipitation, and wind. These climatic conditions, in turn, determine the types of aquatic ecosystems that can thrive in a particular area and the species that inhabit them.5 Understanding these geographical controls is essential for predicting the potential and limitations of fisheries in different regions.

The relentless march of urbanization, coupled with the growing uncertainties of a changing climate, casts a long shadow over the water security of our cities. Unlike their rural counterparts, urban areas face a distinct and often amplified set of challenges when drought strikes. The intricate web of municipal water supply, the concentrated demands of industry and commerce, and the sheer density of population render urban centers particularly vulnerable to the cascading impacts of water scarcity. When the taps run dry or restrictions tighten, the repercussions extend far beyond parched lawns and wilted gardens, impacting public health, economic stability, and the very fabric of urban life This chapter serves as an entry point into the critical field of urban drought management. We will delve into the unique characteristics that distinguish urban droughts from their rural counterparts, highlighting the interconnectedness of water systems and the amplified socioeconomic consequences within city limits. We will explore the increasing frequency and intensity of these events, driven by both natural climate variability and

Normally we associate our agriculture and food supply with farms and villages. The new trends of greener cities and urban and peri urban horticulture (UPH) are emerging very fast. Towns and cities in the world’s developing countries are growing at great speed. Ten years ago, an estimated 40 percent of the developing world’s population or 2 billion people lived in urban areas. Since then, their numbers have expanded twice as fast as total population growth, to more than 2.5 billion. By 2025, more than half the developing world’s population of 3.5 billion will be urban. Again most of the world’s fastest growing cities are in Asia and Africa with young population.

Urban climatology deals with changes in climatic conditions that prevail in large cities and towns that differ from the surroundings. Urban climates are influenced by large built-up areas, increased human activities and dense population and are found to experience differences in temperature, humidity, wind speed and direction and rainfall compared to adjoining areas. Tall buildings, paved streets and parking lots affect radiation balance, wind flow and run-off. The atmosphere in urban areas will have higher concentration of pollutants like carbon monoxide, oxides of sulphur and nitrogen, hydrocarbons, oxidants and particulate matters. Heavy concentration of air pollutants will have considerable impact on temperature, humidity, wind, and precipitation in and around urban areas. Heavy concentrations of air pollutants for longer periods or several days may lead to temperature inversions. The temperature inversions prevent convection and vertical movement of air. The centre of urban area will be warmer by even 5 to 6°C compared to adjoining areas. During summer months, the concrete structures absorb, store and reradiate more solar energy per unit area compared to vegetation. During nights, radiative losses from urban buildings and roads keep city warmer than the rural areas. The average relative humidity in cities is usually lower due to lack of evapotranspiration from vegetation. The mean wind speed will be 20 to 30 percent due to increased frictional drag induced by built up urban terrain (Fig.17.1).
The urban areas influence precipitation patterns in its vicinity as turbulence and convection get modified by city environment.
17.1. Urban Heat Islands
An urban heat island is a type of microclimate that is created when an urban area becomes warmer than the surrounding area. It is common in large cities (Fig.17.2). The characteristic features of urban heat islands are as follows:
• Increased temperature
• Large temperature difference by even 5 to 6°C
• The south facing buildings receive more sunlight in the northern hemisphere
• The tall buildings in urban areas create streets that act like deep valley
• The albedo will be very less. The darker areas lead to more absorption of incoming solar radiation and emit more of long wave radiation
• The concrete structures are built with materials having low specific heat. Therefore, concrete structures warm up faster and lead to quick rise in temperature
• The higher density of buildings reduces wind speeds.

Abstract

The desert environment is one of the most challenging environments for human habitation. Inhabitants have to deal with climatic factors such as high temperature, sandstorms, flash floods and lack of water due to low rainfall. The people of Saudi Arabian desert had developed various traditional adaptation approaches such as living in tents, wearing head dresses, settling close to source of water, using camel for transportation, irrigation farming and traditional land management (hema). In recent times, modern technologies for air conditioning, transportation and housing have replaced the traditional adaptation methods especially in the cities. The modern technologies have reduced the challenges faced by the traditional society but has thrown up new challenges to sustainability. The new issues include urban flooding, depletion of underground water, high energy demand and consumption and loss of natural habitat to urbanization. This chapter reviews the traditional and the modern adaptation techniques in Saudi Arabia especially in the urban areas. It examines the implication of the changes for urban sustainability and explores different approaches for reducing the negative impacts. The chapter also dwells on the role of geospatial techniques in adapting to the desert environment.

Introduction

In addition to role of iron oxidation in commercial point of view there are certain implication of iron oxidation on environment. Acid Rock Drainage (ARD) is one of the example of environmental pollution. Coal and various metal ores are enclosed in geological formation of reduced nature. Coal, is often associated with pyrite (FeS₂).When mining activities expose this material to atmospheric oxygen, a combination of auto oxidation and microbial iron and sulfur oxidation produces large amounts of acids. The iron-rich acidic mine drainage kills aquatic life and renders the contaminated stream unsuitable as a water supply or for recreational use.

Abstract

Aquifers are usually composed of permeable layers that can ways a considerable amount of groundwater. Usually, aquifer units are correlated through the concept of lithostratigraphy. For low-permeable aquifers, it is difficult to define the spatial distribution of hydrogeological units, and this study attempts to use geochemical methods to identify the groundwater flow paths in an area of Southeast coast of Tamil Nadu, India. Multiple geochemical analyses, including groundwater chemistry; stable isotopic compositions of d¹⁸O and 8D contents were performed.  Spatial distribution of d¹⁸O, dD, Cl-/HCO-₃ show that northeastern part of the study area seriously affected by seawater intrusion. The highly permeable aquifers at the east coastal region are characterized by high hydraulic conductivity as compared with other regions of the study area. Hydrogeochemical characteristics based on bivariate diagrams of major and minor ions show that changes in the chemical composition of groundwater are mainly controlled by the salinization process followed by cation-exchange reactions.

Abstract

The weather or climate is a natural resource and is an important basic input in agricultural planning and strategies. Every plant process, related with growth, development and yield of a crop and each of inseason and off-season farm operations (according to World Meteorological Organization) is more than 10 per cent and can reach up to 50 per cent in smaller areas and not a surprise even if it reaches to 100 per cent on micro scale. Amongst the various weather elements, temperatures, radiation and rainfall play major role in deciding the crop growth and yield levels. Precipitation is one of the important weather factors being responsible for atmospheric and soil moisture and therefore has more agricultural importance, especially in rainfed agriculture.

Keywords: Remote sensing, weather, agroadvisory, GIS

1.0 Introduction

India receives more than 70 per cent of its annual rainfall during South West monsoon season. Indian summer monsoon rainfall shows large intra - seasonal and intra-annual variability (Parthasarathy, 1960; Alexander et al., 1978; Mooley and Parthasarathy, 1984) and also changes in space and time, intensity and distribution. Borgaonkar and Pant (2001) have reported that Indian monsoon rainfall has shown trend less nature since 17^th century based on proxy data with large inter-annual fluctuations. IPCC (2001) has reported increase in rainfall over tropical and higher latitudes and decrease in rainfall over subtropics and mid latitudes.

16.1 Introduction

The ancient Greek philosopher ‘Heraclitus’ said, that, “You can’t step into the same river twice”. By this, he meant that permanence is an illusion and changes are inevitable. One of such changes, which has created buzz all over world is climate change. To understand the science behind climate change, the first step would be to know about the periodic changes in earth’s climate. Scientists devised innovative techniques to recover evidence from the distant past, first from deposits left on land, then from sea floor sediments, and one of the finest techniques of drilling deep into ice. Evidences from past climates help us to understand the evolution of the earth’s atmosphere, oceans, biosphere, and cryosphere. At the same time, paleo-climate studies help in quantification of properties of earth’s climate, including the forces that drive climate change and the sensitivity of the earth’s climate to those forces. When scientists investigate causes or complex processes in the present and future, they may find evidence in the past that helps them in mapping out the complexities (McMullen and Jabbour, 2009). The paleo-climatologists succeeded brilliantly and discovered strangely regular pattern of glacial cycles, which helps in prediction of future changes.

14.1.2 How it Works
• Temperature Rise: When the temperature rises, the alcohol in the bulb expands, pushing the mercury up the arm on the maximum temperature side. The mercury pushes the index upwards, and this index stays at the highest point reached as the mercury falls back down with decreasing temperature.
• Temperature Fall: When the temperature falls, the alcohol in the bulb contracts, pulling the mercury down on the minimum temperature side (and thus up on the maximum side). The mercury on the minimum side pushes its index upwards. As the temperature rises again, the mercury retreats, leaving the minimum temperature index at the lowest point reached.
• Reading the Thermometer: To read the maximum temperature, you look at the lower end of the index on the maximum temperature scale. To read the minimum temperature, you look at the lower end of the index on the minimum temperature scale. The current temperature can be read from either side by noting the position of the top of the mercury column.
• Resetting the Thermometer: After taking the readings, the indices need to be reset. This is typically done using a small magnet to pull the steel indices back down to the current level of the mercury.

Abstract

Climate change is today’s major concern throughout the world. All sectors have been influenced with the impact of climate change. Similarly, agriculture sector has also been affected with the worse climatic changes. All components of agricultural production system like water, soil, vegetation, organism and microorganism etc. affected greatly due to climatic abruptions. And thus, the productivity is hampering day by day. Today, we requires to predict the trend of changes in climatic parameters like maximum and minimum temperature, humidity, wind speed, sunshine hours etc, to project future change in these climatic parameters, to assess the effect of theses climatic parameters on agricultural components like water resources, soil, vegetation, organism and microorganism and, also to find the adaptation and mitigation strategies.  All these works have beenmainly done by manual methods earlier. Developed country like USA, Japan, UK etc adopted the computer modelling to climate change research. Computer modelling and software assistance have been adopted slowly in developed countries. Since, climatic changes requires processing of very large number of data, they needs computer and software assistance. Without computer assistance climate change research seems to be impossible.

ABSTRACT

Synthetic Aperture Radar (SAR) images are being used more extensively than ever before for geosciences Applications in the moist tropics. With SAR's side viewing geometry, longer wavelengths, and almost all-weather sensing capability, SAR imagery has been extensively useful mapping tool for coastal geomorphology in the moist tropics. The purpose of this study to assess the use of Multitemporal C-band ENVISAT- ASAR data for identification of different coastal geomorphology in part of Tamilnadu coast. The orbital ASAR data was digitally geometric corrected (ortho-rectified) and filtered for speckle noise, and linearly stretched in order to enhance contrast between the coastal environment features. By using the methods of crisp enhancement, linear stretching and PCA, to show the various Coastal geomorphological units. The information extraction is based on recognition of the mechanism interactions occurring between radar signal and the target on the ground, represented by shallow water morphology in the intertidal conditions, coastal dunes, mangroves, marshes and highland. In an application perspective, Orbital ASAR data proved to be a fundamental source of information for both geomorphological mapping and land use pattern in moist tropical environments.

Key Words : ASAR, Geomorphology, Mangroves, Land Cover, Coastal mapping.

ABSTRACT

Of late, the importance of integrated study of multi-theme data is being realised in geological mapping and mineral exploration programmes. The usefulness of such a study lies in the fact that data integration and interpretation in a conjunctive mode enables to infer more information than the sets can separately provide. The present paper presents several case studies, illustrating the usefulness of multi-theme data integration in geological mapping and mineral exploration.

1. INTRODUCTION

Integrated study of multi-theme data is being practiced in the recent times in the geological mapping and mineral exploration campaigns. Such a study, in a synergetic fashion, helps to extract more meaningful information than from the study of individual datasets. It not only helps in deciphering regional geological picture, but also in the precise location of drilling targets, thereby yielding rich dividends for the expenditure incurred in the mapping and mineral investigations. Besides, the success ratio of the mineral investigations has also shown a significant increase, resulting in the discovery of more mineral

deposits. Hence the integration of multi-theme data is of paramount importance for the success of geological mapping and mineral investigations.

ABSTRACT

Spectral signatures are the specific combination of reflected and absorbed electromagnetic radiation at varying wavelengths which can uniquely identify an object. The “Spectral signature” of an object is a function of 1) incidental EM wavelength and material interaction with that section of the electromagnetic spectrum. The measurements can be made with various instruments, including a task specific spectrometer, although the most common method is separation of the Red, Green, Blue and Near Infrared portion of the EM spectrum as acquired by digital cameras. The spectral signatures serve as diagnostic tools in understanding the composition and structure of the materials. The present paper highlights the usefulness of the spectral signatures in rock and mineral discrimination and mineral exploration and stresses the need for creation of a spectral data base in India for various applications.

1. INTRODUCTION

Objects at the Earth's surface emit and reflect many wavelengths of radiation. In principle, each object has a unique spectral signature, which could be used for identification much like a finger print. Remotely sensed spectral signatures could be utilized for recognizing and mapping for all kinds of features. This can be done to a limited extent with conventional multispectral scanners that operate in a few broad bands of visible and infrared energy. However, broad spectral bands often do not distinguish between similar features. To overcome this limitation, a more sophisticated approach toward spectral signatures has arisen during the past few years. This approach is called image spectroscopy or hyperspectral analysis, which is based on scanning hundreds of closely spaced and very narrow spectral bands. With this technique, it is possible to create continuous spectral response curves, which may be used to identify many objects positively.

5.1 Introduction
One of the main methods for cost avoidance and prevention is value engineering/ value analysis. “Society of American Value Engineers (SAVE)” states that value Analysis is the systematic use of known procedures which determine the function of a product or service, define a monetary value for the function, and provide the essential function reliably at the lowest overall cost. If these are applied to a new product, it is called value engineering. By analysing the function of any product, material part, component, system, or service, it is possible to find extraneous expenditures connected with them and effectively remove them without compromising the product’s quality, functional dependability, or ability to provide services. The principles and steps of value analysis/ value engineering will supplement the effort of design thinking.
5.2 Symptoms for Introducing Value Analysis (VA)
If one or more of the following symptoms exist, starting a VA programme is expected to yield very positive effects.
i. Sales of the company’s products are declining.
ii. The prices of the products of the company are greater than those of the products of its rivals.

Introduction

Soil is a dynamic natural body, characterized by high degree of spatial variability due to combined effect of physical, chemical or biological processes that operate with different intensities at different scales (Goovaerts 1998). Reports have shown that there is large variability in soil properties, crop yield, disease, weed etc., not only in large-sized fields (Godwin and Miller 2003,Vrindts et al. 2005), but also in small-sized fields (Bhattacharya et al. 2008). Therefore, knowledge of hydro-physical properties of soils is crucial for management practices for all kinds of agricultural practices for efficient utilization of input resources. Plant growth and development is highly related to soil hydro-physical properties, which not only depend on soil intrinsic textural and chemical characteristics (Hamza and Anderson 2005) but also on soil management.

Soil physical properties which change with the variation in soil structure include bulk density, total porosity, pore geometry (size distribution, shape, continuity and tortuosity), penetration resistance and aggregate stability, consequently affecting soil hydraulic properties such as water retention characteristics, plant available water capacity, infiltration capacity and saturated hydraulic conductivity. These soil properties are dependent on seasonal climatic conditions, management practices, crop development and biological activity (Reynolds et al. 2007). The hydro-physical properties of soils, i.e., water retention and water permeability in both saturated and unsaturated zones not only shape soil water balance but also decide the conditions for plant growth, development and yield. They also determine water availability for the plant root system and the transfer of water with chemical compounds dissolved in it into deeper layers.