eChapters

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

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

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

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.

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".

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

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

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

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".

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

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

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

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 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 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 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 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.

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.

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.

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

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.

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.

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:

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.

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.

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.

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.

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.

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.

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).

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).

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.

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.

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.

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.

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).

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).

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.

5.1 Introduction

In recent decades, human induced changes in climate of the earth have the focus of scientific and social attention. The most imminent of this is the increased concentration of greenhouse gases (GHGs) namely, carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) in the atmosphere. The concentration of CO₂, CH₄ and N₂O have increased markedly by 30%, 145% and 15%, respectively as a result of human activity since 1750, the era of Industrial Revolutions (IPCC, 2007). Between 1750 and 2005, the concentration of CO₂, CH₄ and N₂O in the atmosphere has increased from 280 to 379 ppm, 715 to 1774 ppb and from 270 to 319 ppb, respectively (IPCC, 2007). However, there was a steep increase during the recent years i.e. 70% increase of GHGs between 1970 and 2004.

4.1 Introduction

Circumstantial evidences almost confirm researchers’ on early predictions of a changing climate and a warming world. The trend of changes also establishes the primary influence of increased greenhouse gas concentration on the global warming and the consequential events. The global mean surface air temperature has increased by about 0.74°C over the last 100 years. It is projected to rise 1.4 to 6.4 °C by the year 2100 (IPCC AR4, 2007). Changes will vary from region to region. Eleven of the twelve years in the period 1995-2006 rank among the top 12 warmest years in the instrumental record (since 1880). The radiative forcing of CO₂, CH₄ and N₂O is very likely (> 90% probability) increasing at a faster rate during the current era than any other time in the last 10,000 years. This is because of the increase in the global abundance of the three key greenhouse gases. The atmospheric CO₂ concentration has reached the level of 389 ppm in 2010 (WMO, 2011) from 270 ppm the pre-industrial era. In addition, global abundance of other greenhouse gases such as methane (CH₄) has increased from 700 ppb in the pre-industrial era to 1808 ppb in 2010 and in the same period, nitrous oxide (N₂O) has increased from 270 ppb to 323 ppb.

3.1 Introduction

Ozone (O₃) is present throughout the atmosphere and can have either positive or negative effect depending on where it is found. The stratosphere (15-50 km) has the largest (90%) concentrations of O₃ (Colls, 1997). Stratospheric O₃ is important as it regulates the transmittance of ultraviolet light to the surface of the earth. Hence reductions in stratospheric O₃ in Polar regions, particularly the Antarctic “ozone hole”, are of concern regarding the health effects of exposure to increased levels of ultra violet (UV) radiation. In the troposphere (0-15 km), O₃ is a toxic pollutant of global importance and it is a major constituent of photochemical smog. Interest in pollutant O₃ and in its effects on living organisms has increased in the last decades as a consequence of the rise in its ground-level concentration and of the widening of its diffusion (Ashmore, 2005). Economic growth requires more energy production, which would result in increased production of NOx and volatile organic compounds (VOCs) precursors for O₃ formation (Ghude et al., 2008).

2.1 Introduction

Weather has always been a popular topic but in the recent past it has received wide attention and debate as the public concern has increased about unforeseen changes in our climate. Over the 20^th century the average temperature of the earth has increased by 0.4 -0.8^oC. This increase is expected to continue and by 2100 the average global temperature is likely to be 1.4 - 5.8 ^oC warmer. One of the anticipated effects of climate change is the possible increase in both frequency and intensity of extreme weather events, such as heat waves, cold waves, hurricanes, floods and drought spells. The warming of the earth may fuel interactions between the ocean and atmosphere that will amplify the frequency and intensity extreme weather events. The possible changes in the frequency, distribution and intensity of extreme climate events have a significant influence at local, regional and global scales due to their multi-sectoral impacts on the overall economy.

1.1 Introduction

Greenhouse effect, regulated by the presence of greenhouse gases in the earth’s atmosphere, is a natural process that plays a major part in shaping the earth’s climate. A continued rise in concentration of the greenhouse gases has led to enhanced greenhouse effect resulting in global warming and global climate change. The impact of human activities on greenhouse gases (GHGs) emission through fossil fuel burning, agriculture and industrial processes is important and familiar to people. This chapter addresses basic principles and physics of greenhouse effect and the role of Indian agriculture in GHG emissions. Agriculture is a potential source and sink to GHGs in atmosphere. It is a source for three primary GHGs: CO₂, N₂O and CH4 and sink for atmospheric CO₂ . Management of agricultural land, land use change and forestry has a profound influence on atmospheric GHGs concentration. The two broad anthropogenic sources of GHGs emission from agriculture are the energy use in agriculture (manufacture and use of agricultural inputs and farm machinery) and the management of agricultural land. Large sections of the India’s population depend on biomass resources like wood, crop residues and cattle dung for energy. In the agriculture sector, besides the CO₂ emissions due to burning of crop and animal waste, India’s large ruminant population and rice fields are significant contributors to CH₄ emissions. An understanding of GHG emissions by sources and removal by sinks in agriculture is important to take appropriate mitigation and adaptation strategies and to estimate and create inventory of GHGs.

INTRODUCTION

Aquaculture had undergone rapid expansion and intensification in the recent past and has taken the shape of a full-fledged diversified industry. But the risk involved in aquaculture activity has also increased significantly due to the outbreak of diseases which has a devastating effect on the aquaculture crops. Fish are aquatic and poikilothermic, their existence and performance are dominated by the quality of their environment . The aquatic environment is a complex system subject to constant physical and chemical changes brought about by natural and manmade processes. Therefore, choosing the proper site to develop aquaculture facility is paramount to its success.

A disease is an abnormal condition of an organism caused by infection, inherent weakness or environmental stress; it prevents the organism from functioning normally which ultimately leads to death (Avault, 1998). In an aquatic environment, there is a profound balancing of relationship between host (fish), pathogen and the environment existing and this is the fundamental concept to disease susceptibility of fish (Snieszko, 1973). A disease organism may be present in the environment or host, but will not cause disease as long as the host has high natural resistant or the physical condition of the host is strong. Once the imbalance is created to any of the component, opportunistic pathogen invades the host resulting to the outbreak of disease.

INTRODUCTION

One of the most important changes in the global environment which affects the existence of all living things , is the climate change. The climate change globally and locally also changes the aquatic habitat which, in turn directly and indirectly affects the environment. Anyway, the changes in climate are certain to occur and may be inevitable. The only possible way is to analyze the situation and find out the reasons for such changes and take immediate steps to minimize the impact of these climate changes. Global warming has eventually become synonymous with climate change because almost all the variables of the ecosystem are influenced directly or indirectly at different levels.

Aquatic environment is extremely diverse and influenced by the climate changes to a large extent both locally and globally. The changes in the ocean and its life are well studied at different levels with all possible details compared to the freshwater habitats. Unlike agriculture and animal husbandry, the vast majority of the fish production still comes from the natural habitat or the wild collections. Agriculture and animal husbandry usually focus on few important species but for fisheries, all the species of fishes including most of the aquatic living organisms are commercially important. The media (water) in which the aquatic organisms dwell, is much more important to all living organisms of the earth and so the influence by climate changes on water becomes very much relevant in the present situation. Freshwater habitats are limited and are much more complex to investigate in respect of climate changes due to the variability and diverse micro and macro level interactions. A holistic approach to deal with all these problems has not got much attention both globally and locally even though , it is the need of the hour to address the issues of impact of climate changes in the aquatic environment.

INTRODUCTION

Prediction of helminthic infections is impractical. The aim of any control programme must therefore, ensure that parasite populations do not exceed levels compatible with economic production. The parasitological monitoring (e. g. faecal egg counts or pasture sampling) at intervals, forecasting on the basis of meteorological data and computer simulation may provide an alternate approach to control parasitic infection (Brunsdon, R. V. , 1980) in a given geographical area. The most common gastrointestinal parasite prevalent throughout the year in Meghalaya, India is Strongyle infection. This is because of the high rainfall and humidity prevalent in the North-Eastern region.

As the prevalence of this infection is mainly dependent on rainfall and humidity, study was being initiated to identify the relationship between rainfall/temperature and strongyle infection. The study would be also helpful in predicting/ forecasting the disease occurrence based on the prevailing pattern of rainfall in a particular location.

INTRODUCTION

Livestock plays a very important role in the mixed farming system of the country contributing about 25 per cent of Gross Domestic Products (GDP) from agricultural sector. India has the largest population of cattle and buffaloes and the highest producer of milk in the world. India has also the second largest population of goats and one of the leading countries in poultry sector. There has been a tremendous increase in milk, meat and egg production since independence. However, owing to various reasons viz. , low genetic potential, scarcity of feeds and fodders, diseases, poor management practices etc. , the productivity is quite low. Climatic conditions of a place have also an important bearing on livestock production and productivity. Climatic factors like ambient temperature, humidity, solar radiation and wind velocity are the important ones which make up the physical environment of the animal having direct and indirect influences on animal’s responses towards climate. Temperature and humidity are the most crucial with the former being the most researched one. Extremes of hot and cold weather are creating stress to any animal and the effects are more severe under hot and humid climate. The varied effects of undesirable climate on animals are pertaining to feed and water intake, physiological, biochemical and endocrinological aspects, reproduction, health and productivity etc. Thus, the positive and negative effects of the environment on the livestock have been discussed in a way to undertake some protective measures.

INTRODUCTION

Edible mushrooms are higher fungi occurring seasonally all over the world in various habitats varying from sandy plains to thick forests. About 2000 fungal species in the world have been identified as edible, of which, only a few (20) are cultivated commercially (Chang and Miles, 1991). These mushrooms are generally considered as the good source of protein, vitamins and minerals in addition to their flavour and condiment value. About 3.

INTRODUCTION

India has varied agroclimatic conditions, which favour the cultivation of various horticultural crops. Based on the adaptability and system of cultivation, the horticulture can be grouped into four major class such as Temperate, Sub-tropical, Tropical and Arid. India has become the second largest producer of both fruits and vegetables with a total production of 46. 75 million tonnes of fruits from an area of 4. 56 million ha and 93. 16 million tonnes of vegetables from 6. 30 million ha (2003-2004). Besides, there is a tremendous scope for increasing the production of flowers, spices and condiments, plantation crops and medicinal and aromatic plants. Floriculture has emerged as a viable agribusiness. The commercial cultivation of flowers in open field conditions was much popular than protected cultivation in India. But, now- a-days, the protected cultivation has brought a great revolution in Indian floriculture and it helps for the quality production and export to earn sizeable amount of foreign exchange. India has approximately 350 ha under green house cultivation with export value of approximately Rs. 330 crores during 2003-04(APEDA). On the other hand, the prevailing climatic conditions in India are highly suitable for cultivation of the almost all spices from tropical black pepper to temperate saffron. The major spices are mainly grown in humid tropics like Western Ghats and NE States. Out of 21 agro-ecological sub regions in India, spices are grown in 14 different agro ecological sub regions. Fruits, vegetables, flowers spices and condiments, plantation crops and medicinal plants are widely distributed across the country, while plantation crops are restricted to a few regions.