eChapters

6.1 Introduction

The change in climatic factors over the years is affecting the entire ecosystem. According to Intergovernmental Panel on Climate Change (2007), the global surface temperature is predicted to increase between 1.4 and 5.8 ^oC by the year 2100. Microbial and plant metabolic processes are often dependent on environmental factors (for e.g. temperature and moisture), enzyme activity, and nutrient availability all of which are likely to be affected by climate change (IPCC, 2007). The global atmospheric concentration of carbon dioxide, an important greenhouse gas (GHG) largely responsible for global warming, has increased from a pre-industrial value of about 280 ppm to 389 ppm at present. Similarly, the global atmospheric concentration of other important GHGs like methane and nitrous oxides has also increased considerably. The increase in GHGs was 70% between 1970 and 2004.

Rising atmospheric CO₂ is able to change the physiological activities of plants and soil micro organisms which in turn control the flow of carbon (C) and nitrogen (N) in terrestrial ecosystems. The change in climatic factors also alters the beneficial plant-microbe interactions, which may be positive, negative, neutral or having variable effects. The survival and activity of microorganisms in the rhizosphere mainly depend on the flow of carbon in the root exudates. The composition of these root exudates is affected by various environmental factors such as soil type, pH, light intensity, oxygen status, soil temperature, soil moisture and nutrient availability. Diverse microbial activities pose a major challenge to predict the response of microbial community to global climate change. These changes in microbial activity have larger impacts on vital ecological processes such as nutrient cycling.

7.1 Introduction

The current atmospheric CO₂ concentration is the highest during last 650,000 to 800,000 years (Luthi et al., 2008), and also probably in the last 20 million years (Pearson and Palmer, 2000). Since last two decades, it is increasing at a rate of about 2 ppm/yr with the current concentration of 389 ppm in 2010 (WMO, 2011). The current trend of energy use based on fossil fuel consumption may raise it to 900 - 1100 ppmby the end of 21^st century (Kiehl, 2011).

8.1 Introduction

Earth’s temperature has increased significantly due to the rise in concentration of greenhouse gases in its atmosphere. Naturally occurring greenhouse gases include water vapour (H₂O), carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O) and ozone (O₃). Prior to industrial revolution, the amount of greenhouse gases released into the atmosphere matched what could be absorbed by the natural sinks. Industrialization catapulted the addition of anthropogenically emitted gases to the environment, much beyond the natural levels. These greenhouse gases are building up, thus creating the effect of ‘global warming’. Global warming is a consequence of two major phenomena - depletion of the ozone layer and increase in greenhouse gas emission (Ishler, 2008).

9.1 Introduction

Background increase in anthropogenic emissions of Greenhouse gases, associated climate change and its global consequences are issues of concern. The Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (FAR) reveals that warming of the climate system is evident from the increase in global average air and ocean temperatures, widespread melting of ice and the rising global average sea level. The report states that the global mean temperature may increase between 1.4 and 5.8^oC by 2100, which will have severe impact on the global hydrological system, other ecosystems, the sea level, and agriculture. The impact could be particularly severe in tropical countries including India. Thus climate change is unavoidable and associated weather extremes such as high temperature and heat waves; increase frequency of droughts and high intensity rainfall causing flood are the issues of concern for Indian Agriculture.

10.1 Introduction

The IPCC predicts the global average surface temperature to increase by 1.4 – 5.8 ^oC by 2100 with the increased atmospheric carbon dioxide (CO₂) concentration from 540-970 ppm over the same period. The atmospheric CO₂ concentration and temperature, both, showing a steep rise since last three decades and their impacts experienced across all sectors of agriculture. Serious concerns have been raised about the effects of global environmental change on community and ecosystem functioning. Climate change scenarios generated from General Circulation Models (GCM) with a doubling of atmospheric CO₂ predicted various extreme weather events viz., warming temperatures, increase in anti-cyclonic behaviour during the summer which may result in 20% increase in the precipitation, and long periods of drought between rain bearing storms.

11.1 Introduction

Agriculture sector contributes 19% to the total greenhouse gas (GHG) emission in India. Combined with land use change and forestry (LUCF), it is the second largest source of GHG emission in India. Initial efforts at dealing with the problem of global warming concentrated on mitigation, with the aim of reducing and possibly stabilizing the GHG concentrations in the atmosphere (UNFCCC, 1992). Even if this stabilization was achieved, sea level rise and global warming would continue to increase over centuries because of the inertia of the earth systems. Mitigation activities are traditionally employed as natural resources conservation measures, but they generally serve the dual purposes of reducing the emission of GHG from anthropogen sources, and enhancing carbon ‘‘sink’’. Forestry sector holds the key to the success of mitigation efforts, and has great potential to sequester carbon through reduced emissions from deforestation and degradation (REDD), afforestation and reforestation, and forest management. India’s vast area of croplands, through cropland management, could be an important area for sequestering carbon in soils. India being the largest producer of rice and livestock in the world, appropriate management can contribute to a reduction of methane emission from rice production and enteric fermentation.

12.1 Introduction

The concentration of greenhouse gases (GHGs) in the atmosphere has been rising from historical levels, primarily due to fossil-fuel burning and land-use changes. These gases have the potential to trap energy from the sun, which may result in global warming, and this has sparked a world-wide concern that emissions of these gases should be reduced below the 1990 levels by the year 2012 (Kyoto Protocol). The international community has recognized the need to stabilize/reduce CO₂ and other GHG emission. The types of farm power, farm equipment and machinery have a significant influence on intensification and optimization outcomes, and on profit. However, until now, agricultural intensification generally had a negative effect on the quality of many of the essential resources such as soil, water, land, biodiversity and the ecosystem services which caused a decline in the yield and factor productivity growth rates. Another challenge to agriculture is its environmental food print and climate change. Agriculture is responsible for about 30% of the total greenhouse gas emissions, while being directly affected by the consequences of a changing climate. It is estimated that global conversion of all croplands to conservation tillage (CT) could sequester 5 billion tones of carbon annually.

In India significant efforts are underway to develop and popularize agricultural machinery and tools for resource conservation through the combined efforts of several State and National Institutions, particularly Rice-Wheat Consortium for Indo Gangetic Plains. The new technologies are encouraging the farmers to take up innovative ways of managing their resources for higher productivity and also providing a way to the scientific community to solve emerging problems of climate change. The farm machinery in conservation agriculture (CA) can reduce the emissions of fossil fuels compared to conventional agriculture by up to 60%. However, the largest contribution to mitigate climate change with CA can be obtained from carbon (C) sequestration and the storage of atmospheric carbon in the soil. The C -sink potential of soils varies depending on climate and production system. On an average 0.1-0.5 t. ha^-l y^-l of organic carbon can be sequestered under humid temperate conditions. Farm equipments like straw shavers and rotavators play a role in residue incorporation in the soil.

13.1 Introduction

Greenhouse gas (GHG) emissions have become an increasingly important topic worldwide due to their effects on global warming and climate change. The effects of GHG emissions on the ecological and socioeconomic vulnerability have already been noticed and will continue to grow regionally and globally in the years to come (IPCC 2007). Carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), hydrofluorocarbons, perflourocarbons, and sulfur hexafluoride are the important GHGs that are monitored by the United Nations Framework Convention on Climate Change (UNFCCC 2008). Global GHG emissions due to human activities (anthropogenic) have grown since the beginning of the industrial revolution with an increase of 70% between 1970 and 2004 (IPCC, 2007).

14.1 Introduction

Atmospheric concentration of CO₂ has increased from 280 ppm in pre-industrial era to 385 ppm in 2008 (+ 37.5%) and is presently increasing at the rate of 2 ppm yr^-1 or 3.5 Pg yr^-1 (1 Pg or petagram = 1 Gt = 1 gigaton = 1 billion metric ton). The increase in CO₂ emission by human activity is attributed to fossil fuel combustion, deforestation and biomass burning, soil cultivation and drainage of wetlands or peat soils. Increase in fossil fuel combustion is caused by high global energy demand of 475 Quads (1 quad = 1015 BTU) and increasing at the rate of 2.5 % yr^-1, especially in emerging economies including China, India, Mexico, Brazil, etc. The world population of 6.7 billion in 2008 is increasing at the rate of 1.3 % yr^-1 and is projected to be 9.5 billion by 2050 before stabilizing at 10 billion towards the end of the 21^st century. There exists a strong positive correlation between population growth on the one hand and CO₂ emission or the energy demand on the other. The People’s Republic of China accounted for 13% of the world’s C emissions in 2002 and that share is projected to rise to 18% by 2025 (Lal, 2004a).

15.1 Introduction

There is now adequate evidence about the impending global climate change and the consequences thereof. The fourth assessment report of IPCC observed that ‘warming of climate system is now unequivocal, as is now evident from observations of increase in global average air and ocean temperatures, widespread melting of snow and ice, and rising global sea level’ (IPCC, 2007). Though climate change is global in its occurrence and consequences, it is the developing countries like India that are likely to face more adverse consequences. Globally, climate change is seen as a failure of market mechanisms wherein the polluters haven’t had to pay for the negative externalities (Stern, 2007) that their economic activities caused.

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.

1.1 Policy Background

Human activities have resulted in the alteration of the composition of our atmosphere triggering change in the Earth’s climate. The world’s population has grown at an alarming rate with a corresponding increase in demand for natural resources, energy, food, and goods. As a consequence of increase in consumption, vast quantities of gases and effluents are discharged that change the composition of the atmosphere and its capacity to regulate its temperature. The rise in the global temperature is caused by the accumulation of the so-called “greenhouse gases”, namely, carbon dioxide (CO₂), methane, nitrous oxide, and chlorofluorocarbons. Energy received from the sun is absorbed as short wavelength radiation and is eventually returned to space as long wavelength infrared radiation. Greenhouse gases absorb the infrared radiation, trapping it in the atmosphere in the form of heat energy.

2.1 Overview of the CDM Project Cycle

The ultimate governing body of the CDM is the Conference of the Parties/Meeting of the Parties to the Kyoto Protocol (COP/MOP). The COP/MOP is the annual meeting of the signatories to the Kyoto Protocol and is responsible for managing the CDM Executive Board and for overseeing its work. The Executive Board supervises the CDM process under the authority and guidance of the COP/MOP; it is fully accountable to the COP/MOP. The Board decides on rules for the implementation of the CDM, as well as making the final decisions about acceptance of methodologies, registration of projects and issuance of CERs. The Board is composed of 10 members and 10 alternates. The CDM Executive Board created an A/R Working Group to specifically oversee LULUCF under the CDM. The A/R Working Group provides guidance to LULUCF project developers and, using expert reviewers, makes recommendations on acceptance or rejection of LULUCF methodologies.

3.1 Overview of the Global Carbon Market in Pre-Kyoto Protocol Phase

At the First COP in Berlin in 1995, the UNFCCC launched a pilot phase of projects to build experience and “learning by doing”. The pilot phase was termed Activities Implemented Jointly (http://unfccc.int/program/coop/aij/aij_np.html). Under the Activities Implemented Jointly, Annex I Parties could implement projects in other countries that reduced emission of greenhouse gases or enhanced removals of sinks. The number of projects registered under Activities Implemented Jointly has been growing since its launch and as of 2002 (the latest report available) there were 157 projects – 45 percent of which are in developing countries. The total amount of money invested by private sector companies as of 2000 was about $160 million. Because of the expectations that sink projects would be included as a mechanism for achieving targets, several pilot projects were voluntarily implemented involving mostly private sector entities (e.g., electric utility companies, oil companies and environmental non-governmental organisations). Between the beginning of 1996 and the end of 2003, 76 transactions involving carbon sequestration in the LULUCF sector were signed, representing 40 million tCO2-e. Relative to all of the carbon transactions that took place over the same period, sink projects accounted for 21 percent of the total number and 23 percent of the total volume. In volume terms, carbon sequestration projects were the single largest project category, and more than three-quarters of this volume was transacted between 1996 and 1999.

As a developing country, India does not have any emission reduction target, but it is able to sell CERs pursuant to the CDM, to large emitters covered by the EU ETS, countries that have emission reduction targets under the Kyoto Protocol, or any other entity that wishes to purchase such CERs for compliance purposes. It can also supply ERs and VERs for the growing voluntary markets.

4.1 Status and Trends

India’s participation in the carbon markets has contributed to the recognition that it is a useful tool in attracting climate friendly investments. India was an early player in the market, and it used the hosting of the Eighth Conference of Parties to the UNFCCC in Delhi in October 2002 to sensitize the business community about the opportunity provided by carbon finance and the modalities of the emerging CDM. In 2004, the growth in the Indian carbon market was fostered by a healthy number of indigenous management and technical consultants, which began to offer services to potential sellers of emission reductions, and the response from primarily the private sector to capacity building initiatives concerning the nascent market. In its capacity as the Designated National Authority (DNA) for the CDM, the Ministry of Environment and Forests (MOEF) also had the foresight to develop simple and transparent rules, whereby project developers can obtain a Letter of Approval (LOA) theoretically within sixty days, which is a key step required for project registration. By the end of 2004, India was the market leader in the forward sale of emission reductions, with 50 % of the supply market. Early successes included the registration of two projects which consisted of the thermal oxidation of HFC-23 generated as a buy-product during the manufacturing of the refrigerant HCFC-22, but also a number of small scale co-generation projects using bagasse, rice husk and mustard crop residues as a source of biomass, and small scale hydropower projects.

There is widespread belief now that forests can be used to reduce the costs of slowing climate change. While the role of forests in the global carbon cycle has long been acknowledged, recent discussions within the context of the United Nations Framework Convention on Climate Change, as well as efforts to write climate change legislation in the United States, have emphasized the role forests might play. The most recent policy efforts have focused on near-term actions to reduce deforestation in tropical countries. The rationale for considering forests at all in the policy mix stems partly from the physical components of the issue. The world’s forest estate is exceedingly large:

RECTAL EXAMINATION

It provides practically all the information required.

It is the simplest, accurate and reliable method with no cost involved.

Things Required

A full arm rubber sleeve with attached glove or disposable plastic glove.
A rubber or plastic apron.
Non-irritant soap or lubricant.

Accurate early diagnosis of pregnancy is essential for successful breeding programme.

Ability is required for successful practice.

Skill is to be developed to indicate the duration within weeks in early and months in late pregnancy.

TRUE ANESTRUS IN A HEIFER OR POST PARTUM COW / BUFFALO

The animal has both ovaries small and inactive

No palpable structures in the ovaries

Animal does not exhibiting estrus signs

CONTRACEPTION DUE TO MISALLIANCE AND TERMINATION OF PREGNANCY IN BITCHES

It is obvious that breeders maintain varieties of breeds but mismating do occur within their own premises and sometimes by unwarranted stray animal.

Misalliance complicates too many other problems.

Incidence of mismating is 15 to 20 percent in canine breeding.

Preliminaries

Section-A : Write True / False

Q.1 Statistics in singular is used to denote a subject (branch) of science.

Q.2 Statistics in plular is used to denote data or methods.

Q.3 The data first time collected is known as primary data.

Q.4 Primary data is collected from published report.

Q.5 Editing of data is not necessary.

Q.6 Consistency must be maintained in data.

Q.7 Baised and unbiased errors are known as statistical error.

Q.8 Arrangement of data in different, rows & columns is known as classification.

Section-A : Write True / False

Q.1 A better and more beautiful way to present the data in a more visual form can be done by means of diagram.

Q.2 Description of data through diagrams and graphs is better for layman.

Q.3 Diagram does not register a meaningful impression almost before we start to think about it.

Q.4 Diagrams are never used by the business man and government agencies for advertisement and educating people.

Q.5 Diagrams do not give visual presentation of data.

Q.6 The diagrams put a rememberance for a longer time in mind of human being.

Q.7 Diagrams facilitate comparison and reveal pattern of data.

Q.8 Diagrams show approximate values of items in data.

Q.9 Diagrams are more attractive, appealing and impressive than tables.

Q.10 Diagrams can be more easily compared and interpreted than the tables.

Q.11 Tables contain precise figures while diagrams indicate approximate figures.

Section-A : Write True / False

Q.1 Dispersion of a given set of values, gives an idea about the homogeneity or heterogeneity of the distribution of values.

Q.2 The measure of scatteredness of a set of values about an average is known as the “measure of variation or dispersion”.

Q.3 The measure of dispersion must be based on all the observations.

Q.4 Measure of dispersion should be amenable to further mathematical treatment.

Q.5 Measure of dispersion should be affected as little as possible by fluctuation of sampling.

Q.6 The measures which express the spread of observations in terms of distance between the values of two selected observations, are known as “distance measures” e.g. range and interquartile range (or quartile deviation).

Section-A : Write True / False

Q.1 If an experiment is repeated under an identical conditions, we generally come to a result (i.e. outcome) which is unique or certain.

Q.2 In an experiment, the result (outcome) may not be unique but it is one of the several possible outcomes.

Q.3 The phenomena described in Ql, are known as “deterministic or predictable”.

Q.4 In deterministic phenomena, the results can be predicted with certainity

Q.5 A deterministic model stipulates that the conditions under which an experiment is performed, determine the ouctome of the experiment

Q.6 The phenomena which do not lead themselves to deterministic approach, are known as “Unpredictable or probabilistic” phenomena.

Q.7 The phenomena frequently occured in business, economic and social science or even in our day to day life, are known as “deterministic phenomena”.

Q.8 A manufacturer can ascertain the future demand of his product with certainity.

Q.9 A sales manager can not predict with certainity about the sales target next year.

Section-A : Write True / False

Q.1 A random variable (r.v) is a real number x connected with the outcomes of a random experiment.

Q.2 In tossing of a balanced die at one time, the number coming on the upper most face of the die is a random variable x which takes any one out of 6 values taken as 1, 2, 3, 4, 5, 6.

Q.3 Let s be the sample space associated with a given random experiment. A real valued function defned on s and taking values in R (-∞,∞) is called one dimensional random variable.

Q.4 In general a n dimensional random variable is simply a function whose domain is S and whose range is a collection of n-tuples of real members (vectors in n-space).

Section-A : Write True / False

Q.1 The average value of a random fenamenon is termed as “Mathematical Expectation” or “Expected value” of random fenamenon.

Q.2 The mathematical expression to compute the expected value of a discrete random variable X with its p.m.f. f(x) is def ned as

Section-A : Write True / False

Q.1 The moment generating function (m.g.f) of a random variable X (about origin having the probability function f (x) is defned as

9.1 Section-A : Write True / False

Q.1 The probabilistic laws for dif erent values of a random variable are made on the basis of given conditions. T ese conditions are known as "prior considerations".

Q.2 If the probabilistic laws are made for dif erent values of a random variable on the basis of results obtained from an experiment, then such results are known as "a posterior inferences".9.1.1 Discrete Uniform Distribution

Q.3 A random variable X is said to have a discrete uniform distribution over the range [1, n] if its p.m.f is written as

Section-A : Write True / False

10.1.1 Normal Distribution

Q.1 A r.v. X is said to have a normal distribution with parameters (μ, σ²) if its p.d.f. is given by the probability law

11.1 Section-A : Write True / False

Q.1 Some assumptions or guesses made about the unknown population parameters, is know as "Statistical hypothesis".

Q.2 For the normal distribution N(μ, σ²), the statement (1) μ = 25.0 and (ii) σ² = 37.0, are known as statistical hypotheses.

Q.3 Let p = 0.5 is the probability of getting a head in single throw of a coin. Ten, this statement is not a statistical hypothesis.

Q.4 The statistical hypothesis under consideration (under test), is known as "Null hypothesis".

Q.5 The null hypothesis is denoted by "Ho".

12.1 Section-A : Write True / False

Q.1 Almost all biological data e.g. crop yield, plant height, seed weight, seed size, protein content in pulse, oil content in oil seed etc. are assumed to be normaly distributed.

Q.2 Let X be a normal variable with N(μ, σ²). The random variable Z def ned as Z = (x - μ)/σ, is known as standard normal variable.

Q.3 The standard normal variable Z is denoted as Z ~ N (0, 1).

Q.4 The p.d.f. of random variable Z is given as

13.1 Section-A : Write True / False

Q.1 The square of a standard normal variate is known as Chi-square variate with one d.f.

Q.2 If X ~ N(μ, σ²) and Z = (x - μ)/σ then Z² is known as Chi-square variate with 1.d.f.

Q.3 If Xi ~ N(μi, σi), i = 1,2,...., n are n independent normal variates then

14.1 Section-A : Write True / False

Q.1 If sample size n is small ie n < 30, then the small sample test is applicable.

Q.2 The exact sample test (small sample test) can be applied to large sample test but the converse is not plaussible.

Q.3 If (x²1 , x²2 ) are two independent chi-square variates with (V1, V₂) degree of freedom then F statistic is def ned as

15.1 Section-A : Write True / False

Q.1 In bivariate distribution if the change in one variable afects a change in the other variable, the variables are said to be correlated.

Q.2 If the change in both the variables takes place in the same direction then the variables are said to have a positive or direct correlation.

Q.3 The pair of variables say, Income and expenditure in house hold or the height and weight of a group of children possess the direct correlation between them.

Q.4 If the change in both the variables takes place in oposite directions, then the variables are said to have "Negative or inverse" correlation.

Q.5 The pairs of variables say (i) Price and demand of a commodities or (ii) Volume and pressure of a perfect gas" have a negative correlation.

Q.6 The two variables are said to have a perfect positive correlation if the deviation in one variable is followed by a corresponding and proportionate deviation in the other variable.

Q.7 There are some funny combinations of variables between which the correlation are said to be "spurious or nonsense".

Introduction

Water preceded all forms of life on earth and is believed to be the very origin of all organic life forms. For ages water was forming oceans, separating landmasses and shaping the terrain. It further influenced the emerging atmosphere of the young planet. The first organism formed and began to evolve in the primeval oceans. Mankind entered into the scene several million years later. The history is rather too long and infinitely complex. Variety of models with different degrees of certitude and consensus attempt to cogently explain what could have happened. But in spite of all the differences on the course of evolution, there is a universal consensus that water played a decisive role in the changes.

Across the globe, mankind managed to establish different civilizations with dissimilar cultural and material advancements much later. But then invariably all civilizations considered water holy and water bodies were sacred places. Holy wells, springs, rivers, cenotaphs were held in awe all through human history. The mysterious properties of water are studied from time immemorial. And water indeed is a strange compound! Availability of water for consumption and agriculture has determined the zenith and nadir of surviving and extinct civilizations.

Ancient Indian temples as part of design, have a prominent sacred well or a pond with an associated purana/myth narrating the mystical properties of the theertha / waterbody. It is still is a living tradition. In the west wishing wells survive from remote antiquity.

Introduction

The science of hydrogeology is defined as hydrology with emphasis on geology. This chapter is to refresh your geology knowledge. The key words are highlighted to assist a quick review.

The Crust and its Composition

The thin outermost layer of the earth is called the crust and ranges in thickness from about 8 km under the oceans to about 25 km on land. It extends under both oceans and continents, and forms the source for all the soils, vegetation, and gases in the atmosphere.

The crust is primarily composed of two elements: silicon and oxygen which account for 75% of the earth’s crust. Note that these are the two elements found in quartz (e.g., sand), which suggests this is the most common of all minerals.

Introduction

Groundwater investigation has a long history. In the past a waterman in the village would walk around the investigation area with a Y shaped wooden fork and identify the location for digging the wells. Certain trees and organic landforms like termite mounds were considered as indicators. The native intelligence of local topography should have played a role in identifying potential location. Successful or otherwise the method can be said to lack scientific objectivity. The optimal groundwater surveying method is no doubt drilling. This method ensures that all necessary information is being brought up from the geological formations. However, in order to obtain a desired degree of information from the subsurface of an area, drilling alone is normally not a feasible alternative.

There are a number of efficient and inexpensive geophysical surveying methods available to the hydrogeologist. It is worth noting at this point that these are, without exception, indirect methods. This implies that no method measures directly what we are actually looking for. With geophysical surveys, the target features are therefore invariably associated features. This implies that unless we understand the water context of these features, our geophysical surveys will be less than meaningful.

Objective methods of investigating groundwater are discussed in this chapter.

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.

Introduction

Large scale exploitation of groundwater using modern deep well boring technology and powerful pumps is the order of the day in India and elsewhere. Increase in agriculture area and year around cultivation of water intensive crops, frequently failing monsoons (Fig.5.1) all have led to drying up of surface water and increased dependence on groundwater.

Thus, given the scenario of over exploitation of the available groundwater, it is essential that proper storage and management of available groundwater resources be identified.

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.

Introduction

The need for water for human consumption and the industry keeps spiraling up in the cities in the wake of rural diaspora and urban sprawl. Groundwater is exploited at an unsustainable rate leading to depletion of aquifers. Worse still is the intrusion of salt water from adjoining coast into the aquifers leading to total wastage of remaining water.

Introduction

Fresh water, a renewable but not an infinite resource, is becoming increasingly scarce. The amount available for use to the world today is almost the same as it was 4500 years ago but global demand has been increasing exponentially. Since 1950, the renewable supply per person has fallen 58 percent as world population has swelled from 2.5 billion to 6 billion. Moreover, unlike oil and most other strategic resources, fresh water has no substitute in most of its uses. It is essential for growing food, manufacturing goods, and safeguarding human health.

According to a World Policy Forum report, the largest and most combustible imbalance between population and available water supplies will be in Asia, where crop production depends heavily on irrigation. Asia today has roughly 60 percent of the world’s people but only 36 percent of the world’s renewable fresh water. China, India, Iran, and Pakistan are among the countries where a significant share of the irrigated land is now jeopardized by groundwater depletion, scarce river water, a fertility-sapping buildup of salts in the soil, or some combination of these factors. Groundwater depletion alone places 10 to 20 percent of grain production in both China and India at risk.

Introduction

All models are but approximations of reality. When we approximate there is always room for uncertainty. The preference of a particular model over the other is the relative degree of uncertainty acceptable to the objective and budget of the study. With the advent of computers, hosts of modeling software promising a lot to the researcher have arrived on the horizon. It is not in the scope of the book to enumerate all the techniques of hydrogeological modeling. Physical modeling using sand tanks was the earliest attempted modeling technique, about 107 years ago. Most recent and significant modeling technique practiced by many in groundwater potential identification is Geographic Information System (GIS) based modeling. After a brief treatment of physical models, concepts of mathematical models and GIS modeling are elaborated. The modeling techniques have involved mathematics and or software specific instructions. Hence it is recommended that relevant text books for individual techniques be referred. This chapter deals more on modeling concepts.

Introduction

Environmental Assessment is taken up in this exercise as a rapid assessment technique for determining the current status of the environment and identifying impact of critical activities on environmental parameters. EIA is a relatively new planning and decision-making tool first enshrined in the United States in the National Environmental Policy Act of 1969. It is a formal study process used to predict the environmental consequences of any development project. EIA thus ensures that the potential problems are foreseen and addressed at an early stage in project planning and design. Creation of Environmental Impact Assessment (EIA) system is vital to conform socio-economic development projects to environmental safety and thereby ensure sustainable economic development. In view of the fact that development is an ever-growing process, its impact on the environment is also ever increasing, leading to rapid deterioration in environmental conditions. As such Environmental Assessment provides a rational approach to sustainable development.

It also enables us in carrying out Environmental Cost-Benefit Analysis of projects at an initial stage. It is thus a precursor to detailed analysis of environmental impacts, which are taken up only if a need for the same is established.

Introduction

In the last two decades global climate change has perceptible and marked impact on the monsoon pattern in India. Delayed and inadequate monsoon has become a recurrent feature and the country is in the grip of drought-flood cycles. Right from the beginning of large scale irrigation that brought green revolution and food self sufficiency to the country, there is a strong feeling that full potential of rivers of the country is not tapped (Table 1).

Metals are toxic and non biodegradable pollutants released into the environment through effluents from agriculture waste, mining, metal processing industries, pharmaceutical industries as well as domestic and natural activities. Metallic pollutants tend to persist indefinitely and eventually get accumulated in the ecosystem. Metals especially arsenic, copper, cadmium, chromium, lead, mercury, nickel, selenium and silver etc. possess a risk to living systems. Conventional processes applied to remediation of metallic pollutants are often restricted due to technical and economical constraints. Particularly when the metal contamination is at very low concentration the conventional methods become inefficient. In this situation application of bioremediation techniques is a technology of choice for environmental protection and clean up.

The Tuppa area, which is located 10-12 km away from Nanded city, and covers an area of about 66 km² was blessed with good , quality of water before industrialisation in this area. With the advent of industries more and more people from this region started complaining about the bad taste & quality of drinking water from dug and bore wells. From 1997 to1999 there was continuous increase in the lateral extent of pollution, with deeper bore wells more contaminated than the dug wells (Kaplay, et al. 2004).

Introduction

Impact Assessment can be broadly defined as the prediction or estimation of the consequences of a current or proposed action (project, policy, technology). Emergence of EIA can be related to National Environmental Policy Act (NEPA) of 1969 in the USA. This act is now considered as model legislation for implementation all over the world. Today we have more than 100 countries that have adopted EIA legislation. EIA requirements of aid agencies and funding agencies are typically based on the principles included in the NEPA. In any project planning, along with the traditional technical (engineering) and economic considerations the NEPA requires environmental impact considerations. Environmental impact statements (EISs) are prepared as action forcing mechanism in NEPA that describe the environmental consequences of major actions which significantly affect the quality of human environment. Thus, the primary purpose of EIA is to encourage the environmental considerations in planning and decision making process. Finally, it is expected to arrive at actions which are more environmentally compatible.

Introduction

The town Paithan is famous by it’s name Dakshin Kashi. Godavari river has pristine glory and great significance for Hindus.

Nath temple is situated on the bank of Godavari river. It is a holy place and that’s why it becomes a place of public gathering on Ekadashi, Aashadi Ekadashi, Poornima, Deepawali, Dasera etc. Every year during Chaitra lakhs of people gather.

But at the time of Sheshti, which occurs once in a year is a special event. Hence many fold increase of congregation compared to other melas. The particular small stretch of river near temple was highly polluted, due to mass bathing and other polluting activities. The warm weather shall alter the photosynthesis rates, biodegradation and affect BOD, DO, pH etc. Recent Nath Sheshti at Paithan during 20^th March to 22^nd March 2006, drew about one lakh of pilgrims and had a few special aspects of interests from an environmental point of view.

Considering all the above aspects, it was decided to assess the changes in quality of river Godavari during Nath Sheshti.