eChapters

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.

ABSTRACT

Granite in the present day context is popularly known as the principal raw material in construction industry and also known for its value addition product as Dimension Stone in the global market. India is in pride possession of much sought granite varieties of the world. No doubt the demand for such granite varieties is quite high both for local and export markets but in reality the failure rate of granite quarries is also high, The technical reasons attributed for such failures being lack of application of proper scientific skill both in selection and mining ofgranite deposits. The past experience in the fieldof granite exploitation has thought us a lesson for application of geological knowledge in selection of right deposits and in adopting the right techniques. The selection criteria for construction purpose and for export market though looks simple, is more complicated in the case of dimension stone granite deposits, the reasons being the requirement of thorough knowledge in petrography,structure,geotechnical characters of the deposit. Considering the importance of the scientific knowledge, the present paper focuses on the various parameters for valuation of granite deposits. In other words, it emphasizes on arriving at a logical conclusion by applying the scientific knowledge in successful exploitation of the much valued granite deposits.

Vector data analysis is performed to convert raw input vector data to output that provides new and meaningful information which ultimately supports decision making and disclose hidden patterns. There are various techniques to analyse vector data like buffering, intersect, union, and so on. Some of the most commonly used techniques with their R-code examples are explained in this chapter.

First of all, you need to import all the packages which are required for performing this exercise. These packages include rgdal and sp for importing and re-projecting vector data as well as raster and rgeos for performing vector analysis operations.

Vector data consists of points, lines and polygons with x, y coordinates known as vertices representing the geographic location i.e. latitude and longitude. Vector data depicts the shape of the spatial feature. Points consist of single x, y locations. Examples of points are tower location, sampling location, etc. Lines represent 1 – dimensional features like roads, streams, etc., and are composed of many or at least two connected points or vertices. Polygons denote 2 – dimensional features like boundaries with three or more vertices that are connected and closed. The vector data are represented in the following figure (fig. 5.1).

Abstract

Visualisation of geological process raises special issues for scientists and animators. The degree of physical movement of a rising arch or along a fault line may be very small compared to the normal terrain variation. Over a long time period the major changes in the environment may come from the more substantial surface manifestations of changing draining regimes. In Tamil Nadu State in South-Eastern India there are continuing tectonic movements arising from the collision of the subcontinent with the greater Asian land mass. Over comparatively recent times (7000 years) these movements have had a major impact on drainage and other hydrological outcomes. The Cauvery River in particular has migrated several hundred kilometers over this period. A mosaic was made from recent satellite imagery and then manipulated to create surface textures for dates between -7000 years and +1000 years. Changes in the terrain surface, such as rising arch structures and descending grabens, have been modelled and animated. The combination of terrain movement and surface change provides a visual history of the period.

Introduction

The continued northward movement (5±6 mm per year) of the subcontinental land mass of India induces substantial tectonic pressures all over India. In the southeast, primarily within Tamil Nadu, there is significant differential movement, both vertical and horizontal, of portions of the existing land mass. This is producing a number of effects:

This chapter introduces the readers about volcanoes and associated features and hazards. Volcanic disasters are like any other geohazards in causing dangerous impacts. However, volcanic explosions are preceded by many surficial expressions that can be detected through satellite imageries, thermal sensors, change in magnetic and gravity anomalies, disappearances of vegetation, sudden appearances of anomalous water vapor, thermal springs and abnormal behavior of animals. Hence, unlike other geohazards, volcanic hazards could be forecast with fairly accurate time limits that may allow evacuation and precautionary safety measures. While avoidance is the best mitigation measure, proper land use planning, provision of scientifically designed damming and diversion methods could save lives and infrastructure from lava flows. Though, atmospheric contamination by volcanic gases, ash cloud and pyroclastic materials could not be thwarted and controlled and thus they could cause havoc.

INTRODUCTION

The term “Volcano” is derived from the name of Roman mythical God of fire “Vulcan”. A volcano is an opening of different shapes, through which, molten rock and gas get ejected either violently or simply flow over earth’s surface. The molten rock and gaseous materials are drawn from deep inside of crust or mantle of the Earth. Repeated ejection of molten materials through vent, fissures or plate margins forms volcanic mountains on earth’s continental or submarine regions.

Volcanism is a threat not only to the lives and infrastructure, but it also drastically alters landscape, impacts atmospheric quality and renders forests, cities and villages and cultivation lands useless. In addition, volcanic eruptions are capable of causing changes in global atmospheric cycles. For example, the eruptions of El Chicho’n in Mexico in 1982, Laki volcano in Iceland and Asama Volcano in Japan in the year 1783 and Krakatau volcano of Japan in the year 1883 have all impacted global climate and atmorpheric dynamics.

The productivity of waste lands is extremely low, and the individuals who own them are impoverished and compelled to work for pay. Wastelands are therefore seen as a potent weapon for combating the problems of poverty and backwardness.
Definitions
Water and land are essential for the development of agriculture. Wasteland is eventually created when there is a decrease of vegetation cover, which causes erosion to take place. Waste lands are large areas of land that have been degraded and are rather difficult to plough.
The National Wasteland Development Board (NWDB) and the Planning Commission established a Technical Task Group. According to this group, wastelands are areas of deteriorated land that are currently underutilized due to various constraints, withthe exception of current use  (CSIR 1990). Depending on the random elements, the wastelands could be categorized under
1. I.erosion caused by water
2. Erosion caused by wind and
3. The Alkalinity and Salinity
The arid, stony, steeply sloped, and snow-covered wastelands are examples of the uncultivated wastelands.

Introduction

Normally, water is a liquid substance made of molecules containing one atom of oxygen and two atoms of hydrogen (H₂O). Pure water has no colour, no taste, no smell, turns to a solid at 0°C and a vapour at 100°C. Its density is 1 gram per cubic centimetre (1 g/cm₃), and it is an extremely good solvent.

An extraordinary property of water is its ability to dissolve other substances. There is hardly a substance known which has not been identified in solution in the earth's waters. Were it not for the solvent property of water, life could not exist because water transfers nutrients vital to life in animals and plants.

A drop of rain water falling through the air dissolves atmospheric gases. When rain reaches the earth, it affects the quality of the land, lakes and rivers.

Water Scarcity Issues
The world is running out of clean water. The subsurface water table decreases and surface runoff rises as a result of deforestation. The amount of water stored underground is decreasing as wells are being dug deeper and deeper. As a result of desertification and deforestation, perennial rivers are turning seasonal. There is not enough potable drinking water because of abuse and overuse.
Conserving Water
• In certain situations, manipulating plants, harvesting water, and other techniques might increase the availability of water supplies.
• Water use reduction achieved by the application of water efficiency or conservation techniques; alternatively,
• Better techniques for managing water can either decrease or increase the useful use of water.
• Any activity, behavioral modification, tool, technology, or better design or procedure used to lower water loss, waste, or use is referred to as a water conservation method.
• One method of conserving water is water efficiency.
Among the Objectives of Water Conservation Initiatives
• The goal of sustainability is to guarantee that water extracted from an ecosystem will not be lost faster than it naturally replaces itself for future generations.
• The pumping, delivering, and treating of water results in energy conservation.
• Habitat conservation includes limiting the amount of water used by humans, which lessens the need to construct new dams and other water diversion infrastructure while also preserving freshwater habitats for nearby species and migratory waterflow.

Ours is a Living Planet because ours is a Water Planet. The health of the Living Planet depends on the health of its water resources. Ironically, the health of its water resources is at stake. And so of its life! The waters of the Earth are in the grips of pollution. Much of the water is already polluted and the rest is increasingly becoming polluted. Water pollution, indeed, is one of the worst problems life on Earth is faced with. Water pollution is halting human progress and is phenomenally affecting all walks of human civilization. Water pollution is even putting a question mark on our sustainable future. This chapter presents the causes, magnitude, and consequences of water pollution and also suggests ways and means to prevent and control water pollution and also attempts to manage water resources.

Introduction
In the global perspective, water contamination is a significant issue. Every day, it is the cause of almost 14,000 deaths. The most valuable natural resource on Earth is water, which makes up more than 70% of its surface.
Definitions
• The term “water pollution” refers to the contamination of water bodies by human activity, which can be detrimental to the plants and organisms that call thesem bodies of water home. It can be characterized as any alteration in the quality of water brought about by human activity that makes it less suitable for any of its positive uses, actual or potential. Excess of any substance or heat that could endanger people, animals, or aquatic lifeMan’s actions alter the quality or composition of water, either directly or indirectly, making it unfit for any purpose.
Sources of Water Pollution
• Point source pollution, which is defined as pollution having a distinct source and point of entry into the water, making it easy to identify. It describes impurities that find their way into a waterway by a covert channel, like a ditch or pipe. For instance, contaminants include metals and organics in municipal and industrial discharge pipelines.

It is estimated that the world requires nearly 70 per cent increase in agriculture production to meet the demand for food by the year 2050 based on current trends in population growth it can be achieved either by increasing land under cultivation (which is not possible), increasing the availability of more water for agriculture and efficient utilisation of available land and water resources. The best available option is to increase in productivity of unit of land for unit water. However, the availability of water for agriculture production cannot be presumed to be same year after year as the major source of water is precipitation more known for its uncertainty due to change in weather patterns from season to season and year to year all over the world. The element of uncertainty is increasing since the beginning of the present century due to climate change under the present circumstance, the crop production is practiced -
• In Irrigated Areas
• In Rainfed Areas
• Under Conserved Moisture Condition Without Any Source Of Irrigation
For increasing crop production under irrigated condition, it is necessary to identify crops and varieties that can produce more yield per unit of water even when there is some decrease in availability of water through irrigation. Therefore, the concept of water production function is used for evaluation of water use efficiency of the crops.

A watershed is an area that provides pathway to the surface or sub surface water flow to a given drainage system. The watershed is a hydrological unit. The area of watershed may vary from few hectares to thousands of square kilometres. The watershed development involves effective management of land and vegetation in order to conserve and improve the quantity of water. The watershed development is a comprehensive and sustainable solution to water conservation (Fig.13.1).
The watershed development has several advantages. It helps in
• Conservation, upgradation and utilization of natural resources particularly land, water and vegetation
• Minimise the inequalities between rainfed and irrigated areas
• Promoting cost effective adoptable simple technologies
• Supply water for domestic ,agricultural and industrial use
• Poverty alleviation and employment generation
• Reducing chemical pollution
• Adopting flood control measures by constructing water storage or impounding structures

Abstract

A huge technical improvement in Information Technology (IT) has made new instruments (e.g. WEB-GIS, Open Source platforms, DBMS with geometric data) available. Distributing geospatial information on the Internet is an enforcing factor for information providers. For dissemination of spatial data, Web-GIS technology can be used, which is amalgamation of several information technologies. Open Source is a philosophy of providing software with better quality, more flexibility, and lower cost. This paper explains the use of Open Source Web-GIS which provides a fast and globally reachable way not only to represent the information about natural resources through maps and statistics but also possibility of processing the information interactively on web.

Keywords : Web-GIS, Open Source, PostgreSQL, PostGIS, GeoServer, Wetlands

1.0 Introduction

India is blessed with diverse and abundant resources. India has been witnessing tremendous growth which has impacted practically every aspect of environment and the common man. Natural resource has been tremendously in use due to increase in population growth, thus generation, dissemination and sharing of information regarding natural resources and data amongst all stake holders have become a necessity. The utilization of modern technologies such as remote sensing, GIS which are effective in management of natural resources as user can store, retrieve and model the spatial information. Web media is playing a vital role in making people aware about the importance and conservation of natural resources. We are presenting such efforts with use of Free and Open Source Software (FOSS) tools.

11.1 Introduction

The laws governing the flow of water in wells are referred to as the hydraulics of wells. Just like surface water flows from a higher elevation to a lower elevation by gravity, groundwater also flows from a region of higher water table to a region of lower water table. This difference of water table measured by any two piezometers divided by the longitudinal distance between them is called as hydraulic gradient. Hydraulic gradient plays a dominant role in deciding the flow of groundwater. This hydraulic gradient together with the hydraulic conductivity of the aquifer material forms the main law of well hydraulics called as Darcy’s law. An understanding of Darcy’s law together with some other laws as discussed subsequently in this chapter is essential in order to know the discharge of a well in a particular formation. Darcy’s law is valid for studying groundwater flow in alluvial formations. However, it is not valid for aquifers having hard rock areas.

Introduction

Wells are vertical shafts excavated or holes drilled in earth to the level of water table for extraction. Digging of wells is an age old practice. Shallow dug wells supported communities in the past. Well water is drawn to the ground manually or mechanically using variety of containers made of metal, leather, canvass and wood or a combination of them. Draught animals or electrical power are used to draw water for irrigation.

Water table (Fig.6.1) wells extend below the groundwater table and extract free water. Pumping water from these wells lowers the water level. The well first gains water from the water bearing material in its immediate proximity. Subsequently a cone of depression is formed in the immediate vicinity of the well. Water outside the cone of depression but with in the area of influence is diverted to replace the body of groundwater finding its way in to pumping well.

Abstract

The present study discusses the cropping pattern changes in Andhra Pradesh agriculture will leads to crop diversification and crop concentration using with Geographical Information System (GIS). Crop data were compiled for the triennium ending period 1980-81, 1990-91, 2000-01 and 2004-05 from various statistical abstracts of Andhra Pradesh. For measuring the crop diversification indices, we have used the Herfindahle index and for crop specialization is measured by using the Location quotient method. The level of crop diversification in the some districts of the state in the eighties is very high. However with the advent of green revolution, there had been a moderate crop unification or crop concentration in the eighties. This trend of crop unification is found to be reversed after 1990-91, though the magnitude of the change is not very striking. The crop diversification is observed to differ across the districts. The level of crop diversification is high in the agricultural backward regions of Rayalaseema and Telangana districts and low in the agriculturally progressive Coastal Andhra districts. During the period 1990-91 to 2004-05, the major trends in crop concentration are increase in the concentration of rice in the districts where it is popularly grown and decline in the concentration of coarse cereal crops, pulses and oilseeds. The concentration of spice crops and fruits and vegetables are also on an increasing trend, which they are popularly grown in their respective districts.

Keywords : Cropping Pattern, Diversification, Location Quotient, Andhra Pradesh, GIS

Abstract

The continental drifting and the movement of Indian plate to the tune of 6500 km in a time frame of 65 million years towards north north-easterly, its collision with Eurasian plate, the rise of mighty Himalayan mountains, the still prevalent northerly directed compressive force which has originally drifted the Indian plate and the disseminated intraplate seismicities have been the proven facts. In this context, a remote sensing based study carried out using IRS satellite images revealed that the whole Indian plate is whirling like a worm with series of alternately arranged E-W trending arches and deeps and N-S extensional/block faulting, NE-SW & NW-SE strike slip faults and E-W trending fracture swarms from Cape Comorin in the South to foot hills of Himalayas in the north. These ongoing tectonic activities have displayed hierarchy of geomorphic anomalies in the fluvial, coastal and hydrological systems and these suggest that the whole Indian subcontinent warrant detailed studies to understand the post drift kinematics and its impacts over the ecosystems, natural resources and natural disasters.

Introduction

Consequent to the continental drifting, the Indian plate has moved towards north northeasterly and collided with Eurasian plate, thus resulting into the rise of Mighty Himalayan Mountains along the junction of these two plate boundaries as demonstrated by many earlier Geoscientists. But the behaviour of the Indian plate, both during the collision and after that, has not been comprehensively studied and understood as to whether it has remained as an inert plate or suffered any mid plate deformations. However, disseminated information has been brought out by many earlier workers on the post trappean arches, deeps, horsts and grabens within the

Indian plate. Some of such tectonic grains from north to south in the Indian Peninsular are: