eChapters

Introduction

Definition of ‘urban’ areas varies from country to country. Consequently, it is difficult to provide a universally acceptable meaning of the term. The difficulty has been summarised by UN (1998) as follows: “because of national differences in the characteristics that distinguish urban from rural areas, the distinction between urban and rural population is not amenable to a single definition that would be applicable to all countries” (UN, 1998). In many cases the divide between a rural and an urban area is based on the minimum population, but the number varies widely between the countries, e.g., 200 in Iceland, 2000 in some countries of West Asia, 5000 in India, and 10000 in Italy! Despite this challenge, most towns and cities are historical phenomena and have their defined administrative boundaries for services and other purposes, including municipalities. These places straight away qualify as the urban centres.

In India, the word has been defined by the Census of India (2001) as: “(a) All statutory places with a municipality, corporation, cantonment board or notified town area committee, etc.; (b) A place satisfying the following three criteria simultaneously: (i) a minimum population of 5,000; (ii) at least 75 per cent of male working population engaged in non-agricultural pursuits; and (iii) a density of population of at least 400 per sq. km (1,000 per sq. mile).” This definition was adopted for the 2011 Census.

Abstract

The UAE Space Reconnaissance Center (SRC) is accounted as a major national and regional source of up-to-date geospatial data, with direct reception of IKONOS, IRS and KOMPSAT satellite imagery as well as access to some other satellite and aerial imagery resources; an activity which covers the whole Middle East region. The main concern in monitoring the environment of UAE and surrounding countries is the desertification process, the monitoring of which requires careful watching of the sand movement and some other relevant features.

This paper throws light on the role of various types of satellite images in monitoring desertification, by utilization of IKONOS, IRS Pan and Landsat TM images covering part of Liwa and Alain areas, representing the two main dune regimes; Liwa and Manadir, which constitutes the northeastern edge of the Empty Quarter sand sea.

The availability of high resolution images makes it possible to detect the yearly or even seasonal sand movements, being controlled by the prevailing wind conditions and distance from the main sand source. The results clarify that movements of up to 25m was encountered at some small sand dunes and about 10m for larger sand dunes, towards the SSE and SSW in Liwa area. In Rimah area a movement of up to 30m was noticed at a small sand dune towards the ENE and about 12m shift in the hinge of a larger sand dune towards the NW. Temporary or permanent ? movement of thin sand sheets can reach 100’s of meters, was easily detected on Landsat images; ~ 25km NE of Alain city. The 5m panchromatic images, on the other hand, helped in tracing sand movements measured in few 10’s of meters, and interpretability of such images was enhanced by merging them with Landsat imagery.

Abstract

The Western Desert covers approximately 700,000 km², which is more than two-thirds of the total area of Egypt. This immense desert, to the west of the Nile, spans the area from the Mediterranean Sea to the Sudanese border. The Great Sand Sea lies within the desert’s plain and extends from Siwa Oasis to Jilf al Kabir plateau. Scarps and deep depressions exist in several parts of the Western Desert. Limited agricultural production, the presence of some natural resources, and permanent settlements are found in the western desert oases (Siwa, Bahariya, Farafra, Dakhla and Kharga), all of which have fresh groundwater. Siwa Oasis, close to the Libyan border, is isolated from the rest of Egypt but has sustained life since ancient times. The Siwa’s cliff-hung Temple of Amun was renowned for its oracles for more than 1,000 years. Herodotus and Alexander the Great visited the temple in the pre-Christian era. The Oasis is a natural depression about 23 meters below sea level. It covers an area of about 1050 km² (2,50,000 acres); of which only 87.95 km² (20,940 acres) are currently cultivated. The total numbers of inhabitants in Siwa were 21,482 in 2006. The main activity in Siwa oasis is agriculture which depends on the groundwater that outflows from about 1199 wells and springs giving a total annual discharge of about 255 million cubic meters from which, about 222 million cubic meters are lost due to evaporation and evapotranspiration, while the remainder goes to the natural lakes of Siwa Oasis. This has led to a continuous rise in the water table level and soil salinity.

Present research paper on land degradation processes relates to the improper management of water and land resources in Siwa Oasis, Egypt.

Abstract

Three seepage tests were carried out for an earth canal at Rawakeeb Research Station (RRS)-west of Omdurman and an average seepage rate of 3.4 m/day was obtained. This value suggests that irrigation canal at RRS should be lined. In addition to that preliminary economic evaluation showed that canal lining is imperative in RRS. A concrete slab form was well designed for lining of RRS canal. Precasting technique and construction technique provided the required water tightness. Economic evaluation was done for RRS canal to investigate the extent of occurrence of supposed advantages, and to estimate costs and benefits and rate of return to lining. The capital expenditure (C), net present worth (NPW) and benefit/cost ratio were found to be 2600.4, 1961.9 and 1.3 respectively which offers a good indicator to adopt the technique.

Abstract

Before 1960’s, UAE was a poor developing country and almost there were no real signs of civilization. During the 1970’s two important things happened: H. H. Sheikh Zayed Bin Sultan Al Nahyan, the president of UAE, and the other Emirates rulers united together and established the United Arab Emirates and considerable oil findings were discovered. The UAE Leadership has proved to have deep future vision; in three decades the country jumped from a relatively backward scattered emirates to a well developed and civilized country.

Development is very obvious : from tents and sandy tracks to tower buildings and highways, from desert to green belts of palm trees and vegetables in all parts of the country, and most important, education, healthcare and all other services became the best in the region. Urban development was so sharp; someone who left the place 10 years ago can hardly know his location and services in all sectors became the best at the international level. The oil money was properly invested in development.

UAE Air Force Space Reconnaissance, used satellite and aerial images for the past 20 years and successfully utilized images from various sources including aerial photographs, Russian satellites images, SPOT and Landsat

Abstract

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

Introduction

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.

Introduction

A society constitutes of several social system and institution such as family, school, religion etc. Every activity of these social systems and institution affect our environment in some way of other. There are various factor bring changes in the society. They are biology, environment, psychology, culture, demography and technology. All these factors collectively contribute to the changes in our society.

Auguste Gomte the father of sociology - defined sociology as the science of society. Sociologist believes that one can study society and understand the laws of society by applying the tools of natural sciences. We need to understand the nature as environment, its nature of work and our interaction with it, to understand and improve the efficiency of working with the nature. The Global deterioration the humanity is facing today is unprecedented in the annals of human history. We are already facing grave, water crisis disasters of all kinds, food, energy and ethical crisis etc. The solution is not visible and may not be visible in near future too. Environmental pollution means contamination in water, air, and land due to the various human activities. Man exploits natural resources to earn more and more profits. Forest is being cut down, the land is spoiled, and the air is becoming fuel and water being polluted. So nature has lost its balance such a situation has leaded us to what can be called as Environmental crisis. The changing lifestyle of our society is one of the main reasons for this crisis.

But unplanned execution of work and excessive industrialization and many other human activities has brought us to an alarming stage. In the face to live a luxurious life style we have been destroying the natural ecological balance.

Introduction

Present work report the study on Jakekur dam situated 4 km. from Omerga

The degradation of dam has occurred not only due to influents inflow but also by sanitation, domestic sewage, agricultural waste, and other activities around the dam like washing cloths, cattle, vehicles, and dumping of solid waste. Apart from it a large number of heavy metals is contributed by corrosion of metal pipe, runoff water from surrounding area during rainy season discharge of decorative paints in water bodies.

Geographical and morphological features of Jakekur dam.

Catchments area : 2110 hector

Gross storage : 10.17 TM C

Full reservoir level : 10 meter.

Length of the dam : 21.25 km.

Height of the dam : 14.80 meter.

Introduction

Environmental problems have come to the forefront as one of the most important issues in transport policy. For a number of pollutants the road transport sector is one of the most significant contributors to environmental pollution. Vehicular emissions have been identified as one of the major contributors in deteriorating air quality in the urban centers. The problem has further been compounded by the concentration of large number of vehicles and comparatively high motor vehicle/population ratios in these cities. Substantial SPM, RSPM CO₂ and No_x are emitted. The problem of air pollution has assumed serious proportion in some of the major metropolitan cities of India. Therefore, CPCB has 296 monitoring stations all over India covering major cities.

The air pollution situation in most of the cities is still far from satisfactory. In India the major air pollution reason is automotive smoke and smoke from industries. New channels are also publishing pollution levels in selected metropolitan cities. The most polluted city in Asia is Pune. The SPM and RSPM levels are displayed at various squares to create awareness among the masses.

Smaller cities like Nanded, Parbhani and Yavatmal are not covered under National Ambient Air Quality Monitoring (NAAQM) scheme of Central Pollution Control Board (CPCB). The National Ambient Air Quality Standards for suspended particulate matters (SPM) are based on gravimetric measurement. Standards for Respirable suspended particulate matters (RSPM) are also based on gravimetric measurement. The development in terms of number of vehicles and building construction has also reached at the doors of these cities and towns. Nanded city having population of 5.5 lakhs has total number of Auto rickshaws more than 5,000. In the present study, Nanded city has been selected to check particulate matters and gaseous pollutants. Since, the city is one of the important Pilgrimage and commercial centre.

Introduction

Water is among the most precious gifts of nature to mankind. Most of the ancient towns of the world grew on the banks of the river, and some of the ancient civilizations are known by the names of rivers. Rivers have always been important sources of drinking water and the means of sustaining human, animal and plant life. Whenever one is dealing with water resources development and utilization, it has to be kept in mind that not only quantity of water but also quality of water is very important. The well being and development of our society is dependent on the availability of water. An increase in groundwater development and utilization for industries and urban water supply has created improper disposal of liquid waste. Defective well constructions, sewage and waste disposal in man made lakes with in the city, open quarries with water and failure to seal the abandoned wells in city area have provided possible openings for downward movement of polluted water into subsurface formations without undergoing the process of natural filtration.

Introduction

Water is one of the most complex natural resources demanding a comprehensive understanding of its inherent features in occurrence and distribution for an integrated planning aimed at optimum development for agriculture, health, industry, power, etc. The well being and development of our society is dependent on the availability of water. An increase in groundwater development and utilization for industries and urban water supply has created improper disposal of liquid waste. Defective well constructions, sewage and waste disposal in man made lakes within city, open quarries with water and failure to seal the abandoned wells in city area have provided possible openings for downward movement of polluted water into subsurface formations without undergoing the process of natural filtration.

Introduction

India is having very rich sources of inland water bodies in the form of river, lakes and reservoirs. The reservoirs are constructed by impounding the river system. The reservoirs are constructed for effective utilisation of water for irrigation, power generation and flood control. Reservoir fishery in India is also important from socio-economic point of view as it has the potential of providing employment to about two million people, Kaushal and Sharma (2001). Total area under the reservoirs in India is 3:1 million ha and it is expected to double by 2020. This includes 19,000 small reservoirs with a total water surface area of 14,85,557 ha and about 180 medium and 56 large reservoirs of 5,27,541 and 11,40, 268 ha area respectively.

The Maharashtra is endowed with an area of 1,79,430 ha under reservoir and the Maharashtra produces 516 tonnes of fish through reservoirs. The state fisheries corporation was operating in 6,272 ha of reservoirs and marketing the catches.

Introduction

In India there are about 200 distillery having installed capacity 1555.5 million liters per annum out of which 50% are of 30 KL/ per day capacity about 50% of remaining distillery are of 45 to 60 KL/ per day capacity there are few distilleries which having go 120 KL/ per day capacity. Distillery waste is one of the major industrial waste having high organic and inorganic constituents in the recent past the treatment and disposal of distillery waste has become a subject of debate of each and every forum.

Introduction

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

Introduction

It has been observed that the surface waters are getting polluted due to improper disposal of domestic and industrial wastewaters. Most of the River basins which are major supply of water for human activities are polluted. Even the groundwater in not spared because of the incessant growth of the population in India. In Maharashtra the number of bore wells has been increased to 5 Lakhs from 1 Lakhs from few decades only. Out of total area of Maharashtra, 82% is covered by the basaltic rocks made up of lava. That’s why the quantity of the groundwater is comparatively less than the Indo-gangetic plane.

Groundwater in the north region of the Tapi River is found to be hard, unfit for the human consumption. The residences of district like Buldhana, Jalgaon and Dhule have to use hard water for consumption. Rampant extraction of the groundwater for agriculture might have caused alternation in chemical qualities of the groundwater. It has been also well documented that in Marathwada region, groundwater content higher concentration of fluoride and total Hardness.

Fluorine the most electro-negative element is of great interest and importance to human health because of its curative and harmful effects. Fluorides are released by various natural sources and anthropogenic activities into the aquatic environment (that is surface as well as groundwater). Fluoride can enter the human body through drinking water, food, toothpaste, mouth rinses and other dental products, drugs and fluoride containing salts and hydrofluoric acid. It may cause Fluorosis – a crippling and painful disease such as dental fluorosis, skeletal fluorosis and non-skeletal fluorosis.

Introduction

Lonar Lake, near Lonar town in the Buldhana District, India is not just the source of excitement for the visitors but also for the scientist community. Lonar is the third largest natural salt-water lake in the world, with a diameter of 1800 meter. Fredrickson, et al (1973) found that, about 50000 year back a massive meteor entered into the Earth’s gravitational forces ranging 60 meter long and weighing 2 million ton. It was racing at a speed of 25 kms per second towards the planet earth. When it struck the earth the energy released was equivalent to that released by six-megaton atom bombs. The impact was so severe that rocks from all sides came on the surface and reached the height of 20 meters. This impact left a massive crater 170 meters deep and with 1800 meter in diameter. Today it is natural salt-water lake.

Introduction

Reservoirs constitute the prime inland fishery resource in the country by virtue of their numerous production potential. These man-made ecosystems offer enough scope for stock manipulation through ecological maneuvering, paving the way for production hikes at a relatively low-capital investment. Unlike the aquaculture systems, where the development is capital intensive, a reservoir fishery development is labour productive and ensures employment for some of the weakest sections of our society.

Introduction

The tropical evergreen forests of the Sahyadris or the Malnad region of Karnataka is one of the richest plant areas (“hot spots”) on earth and crucial to the oxygen supply of the world. More than 30,000 varieties of wildlife and plants and over 8,000 said to unique are reported to lie here. Unless reckless deforestation is halted soon, some scientists fear that within the next 100 years this virgin forest could become an arid wilderness.

Agriculture is one of the major age-old occupations of human beings providing food to the people and also supplies raw materials to a number of agro based industries. However the expansion of agricultural fields in the dense woody forest areas has brought about many environmental problems and thereby degraded the quality of environment in ecologically most sensitive areas like Uttar Kannada District. In India, agricultural practices are primarily based on the traditional system of intensive subsistence forming. It is also observed that more and more available area (forest) has been brought under cultivations to feed the population which has been growing at an alarming rate. The agricultural expansion and population growth, in forest areas of Uttar Kannada Districts have degraded the quality of environment.

Industrial revolution took place in England during the period of 1760-1830. Accordingly, the production prior to demand was introduced. Many countries all over the world adopted industrial policies favouring industrial sector to achieve the fast development of the nation. Government of India also contributed its efforts in the same direction and issued the industrial policy of 1948, 1956, 1977 and so on making several financial and non financial facilities available to have substantial growth and development of industries in particular and nation in general.

Under the name of globalization and making the economy internationally competent, India took a revolutionary decision to follow new industrial policy 1991 opening the doors for investment from foreign countries and private sector even. In addition to this economic reforms have been adopted and advocated for the sake of national development. Three ‘D’ programme consisting of devaluation, decontrol and disinvestment, were also put on the national agenda, to achieve the set targets.

Since the last decade discussion regarding ecology is being heard. A campaign with a great planning has launched by holding seminar conferences and meets. The ecological problem became a matter of tremendous panic and anxiety. Not only in India but also in entire world this problem is being discussed through all school, colleges and universities on international scale all over world, since it became universal issue now a days. The word ecology was not known to the people 20 years ago, never the less it became familiar even among the villages today. The people in villages are making thorough study of the subject. The experts of ecology from all over the world have been surprised to learn the exhaustive study of the same done by the Indian scholars. We have instituted a separate ministry to look after the environmental problems. The activities injurious to environment are prohibited. An act is there to restrict antienvironmental deeds what made scientists all over the world to take this matter so seriously. Does it mean that the very existence of mankind has been jeopardized by it Let us see what our ancient literature say about the ecology and pollution.

Introduction

The natural hazards like floods, cyclones, droughts, landslides and earthquakes are not rare or unusual phenomenon. India is among the world’s most disaster prone areas and a large part of the country is exposed to such natural hazards, which often turn into disasters causing significant disruption of socio-economic life of communities leading to loss of life and property. It would not be considered as a disaster unless it resulted in actual damage to human life or property. According to data accumulated over past 25 years, natural disasters in Asia accounts for about 40% of the world’s total disasters while the death toll ratio is about 50% and the number of people affected is about 90%. The latter figure is about 2.2 times the ratio of number of occurrences in Asia. The figures vary widely over the decades, a result that can be attributed to a few particularly terrible disasters. Such as the 1976 Tangshan Earthquake in China, which killed about 250,000, and a series of severe cyclones that hit Bangladesh in 1970 with a death toll of about 500,000. The death toll resulting from wind and flood disasters jumped by an order of magnitude in the 1990s. But this sudden increase affected Asia’s ratio to the world total by about 15 percentage points because there was a worldwide surge in this type of disaster. Clearly, there is an extreme concentration of victims of such disasters in Asia, Another substantial increase is clear in the value of damage caused by typhoons and cyclones; it is now running at 10 times the level of the 1980s. Again, however, the ratio has remained almost unchanged, at about 40%, because hurricanes in Central and North America account for more than 50% of the world total (51.2%, 58.5%, and 54.4% in the 1970s, 1980s, and 1990s,respectively). It is sadly worth noting that there has been conspicuous growth in the absolute value of damage in both Asia and the Americas.

Introduction

Disaster is defined as a serious disruption of the functioning of a community or a society causing widespread human, material, economic or environmental losses, which exceed the ability of the affected community or society to cope using its own resources (ISDR 2002).

Disaster in Global context - The impact of natural disasters in terms of human and economic losses has risen in recent years, society in general has become more vulnerable to natural disasters. Those usually most affected by natural and other disasters are the poor and socially disadvantaged groups in developing countries as they are least equipped to cope with them (IFRC 2001).

Introduction

Natural Disasters are inevitable, and Indian subcontinent is prone to all type of Natural Disaster either it is flood, drought, cyclone, earthquakes, tsunami or forest fires etc. Disasters can be classified in several ways. A possible sub-division of disaster is: (i) Natural Disasters; (ii) Human made disasters; (iii) Human induced disasters. Another sub-division is related to the main controlling factors leading to a disaster. These may be meteorological, geomorphological/geological, ecological, technological, global environmental and extra terrestrial. Another useful distinction that can be made between disasters is regarding their duration of impact and the time of forewarning. Some disaster strikes within a short period with devastating outcomes; others have a slow onset period with equally or more serious repercussions. According to the available statistics 60% of the total area of Indian subcontinent is venerable to seismic activity of varying intensities, 16% of the country’s total area is drought prone. In India 68% of total sown area of the country is drought prone. Coastal areas of India is exposed to tropical cyclones, tsunami in recent years and among all the disaster occur in the country, River floods are the most frequent and often the most devastating.

Introduction

Disasters are the natural and man made extreme events which exceeds the tolerable magnitude of any event, where adjustment is difficult. These events are catastrophic and results in the loss of life and property on a huge scale. These abnormal events form the headlines to the newspapers and media a world and national level.

These processes are beneficial to the human beings because they form the earth and habitable planet for the evolution of life. However, these processes within a short time limit forms, hazardous and such activities adversely affect the human beings and human related activities on a very large scale.

Amongst the three important types of disasters viz. natural, anthropogenic and technological, the first and the foremost natural disaster mainly includes the geological atmospheric and other related natural types viz. floods, earthquakes, cyclones, tsunamis etc.

Introduction

A disaster is the result of an immediate situation or the result of a long, set process, which disrupts normal human life in its established social, traditional and economic system. This is due to the destruction of environment which is caused by extraordinary natural destructive phenomena or human-induced hazards resulting in human hardship and suffering beyond recovery unless external aid is brought in.

Introduction

Earthquakes are the most destructive among all the natural hazards. Most of the time, they occur without any warning, which makes them most feared and unpredictable natural phenomena. Globally, on an average two earthquakes of magnitude 8 are known to occur every year. Some of the countries like Japan, China and United States have suffered several damaging earthquakes in the past. India has also experienced a number of high intensity earthquakes in the recent past and more than 650 earthquakes of magnitude >5.0 have been reported in India since 1890. Sixty-nine earthquakes in Delaware (U.S.A.) have been documented or suspected since 1871. Refer to Baxter (2000) for more details about the DGS Seismic Network and for documentation of earthquakes. In the 1930s Charles Richter developed a magnitude scale (Richter scale) which was an objective way of discriminating between large and small shocks using the seismic wave amplitude recorded by seismographs (Richter, 1958).

Introduction

The state of Maharashtra now again reels under the scarcity of water. Geologically, major part of the state is covered by Deccan basaltic flows. This basaltic terrain, as such, has been labelled notorious as far as the availability of groundwater is concerned. Uncertain availability of groundwater in the terrain is due to heterogeneity in the nature of piles of basaltic flows which adversely affects the geohydrological characters of the rocks.

The area understudy is unfortunately, a part of basaltic terrain in which no storage structures like major dams or medium projects have been constructed across the existing rivers. Consequently, the irrigation in the area and domestic needs of the people solely depend on whatever water is available in the existing dug wells. The wells do not suffice the need of the people because the percolation of water in the wells is not adequate in major part.

Introduction

On 26^th December 2004, the Indian coastline experienced the most devastating tsunami in recorded history. The tsunami was triggered by an earthquake of magnitude Mw 9.3 at 3.316ºN, 95.854°E off the coast of Sumatra in the Indonesian Archipelago at 06:29 hrs making it the most powerful in the world in the last 40 years. In recent years increasing the vulnerability to natural disasters of developing countries is a major reason for concern. The potential loss of human lives and property due to natural hazards is very high in the urban areas of these countries. The Information obtained from conventional tsunami hazard maps does not always provide sufficient data for users .needs. The difficulty in presenting more significant information on tsunami hazard maps in conventional paper format is due to the limited available physical space of that format. Printing more information on such paper maps tends to confuse rather than provide more needed information to users. Furthermore, these kinds of maps provide little opportunity for users to ask for additional information, to determine the relationships between different kinds of information and important quantitative analyses. Furthermore, Tsunami hazards have important temporal attributes. Presenting these attributes on the map; e.g. the sequence of volcanic eruptions in a region or the frequency of tsumani in a particular area during a particular period of time is very difficult.

Introduction

The Rispana river is a order of stream forming a tributary of Ganga. Its watershed covers an area of approximately 53.6 Km in the northern part of Dehradun city lies between 78^º30’ to 78^º15⁰’ longitude and 30^º15’ to 30^º 30’ latitude in top sheet No is 1/3. The area is covered in IRS - IC Pan of 13 Jan 1998 and LISS-III of 7 March 1997.

The Doon Valley is enriched with numerous seasonal and perennial streams. Which forms the lifetime or the inhabitants . The Rispana river is the part of the Ganga system of Drainage of the valley. The river originates from the Mussoorie hills, which are full of natural springs. The droplets from the springs collect and form numerous streamlets and these streamlets are joined to be these and they form the famous Shekhar Falls (north of Shahanshai Ashram about 5 Km away). Then the Rispana flows along Rajpur road over the Doon Gravels and then river passes through the tiny hamlets Nalapani, Raipur, Chanderroad, Defence colony, Amwala, Tapowan, Dandadhoran Adohiwala, Dalanwala, Gujram, Ajabpur and finally its contribute the water to the suswa River which intern joins the Ganga.

Introduction

The Himalayan Moutains that is relatively a younger formation and geologically a very complex occupies most of the Arunachal Pradesh. The mountain terrain covers an area of about 86000 sq. km with elevation ranging from 400 to 6000 m above mean sea level (Satapathy and Dutta 1999). The wet tropical and sub-tropical climate which prevails in most part of the Arunachal Pradesh, there is usual phenomenon of erosion and land degradation by the action of water. It is estimated by the application of USLE for Arunachal Pradesh that the total amount of about 669.35 million tones of soil is eroded annually with an average rate of 90.7 tonnes /ha/year (Singh, 1999).

Arunachal Pradesh falls under upper Brahamaputra river system constituted by 10 major river basins. They are Tawang, Kameng, Dikrong, Subansiri, Siang, Sesseri, Dibang-Tellu, and Tirap-Tiso. In Arunachal Pradesh, Dikrong river is named after joining of two main rivers Pachin and Para . In the catchments of Dikrong river light textured unstable soils with the prevalent practice of Jhum Cultivation makes the entire catchments susceptible to erosion. In every monsoon the river Dilrong carries tremendous amount of silt, gravel, small boulder and causes flood in some parts of the catchments susceptible to erosion. Singh (1999) observed that loss rate through Dikrong River was 100.98 tones/ha/year. This indicates serious threat to soil resources and there is need for urgent treatment for sediment control in Dikrong river bash.

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

The debate on climate change is going on. From the report of the Inter Governmental Panel on climate change (IPCC), a premier organization set up in 1998 by the World Meteorological Organisation and United Nations Environment Programme, it is known that the average surface temperature has increased over the 20th century by about 0. 6ºC. The number may seem insignificant but it is an unprecedented rise. In the past 150 years, the 11 hottest years were witnessed. It says that 1990s was the warmest decade and 1998 the warmest year since 1861. Worse, the Artic is warming twice as rapidly as the rest of the world and there is a distinct possibility of the Greenland Ice Sheet collapsing altogether and pushing up sea levels by several metres. It is predicted that 2035 is the year when Himalayan glaciers may totally disappear causing catastrophic disruptions. Unfortunately, India is among the countries that will suffer the most serious consequences as a result of global warming. Following is the probable effect of global warming.

INTRODUCTION

Research in agriculture and allied activities and the subsequent technological innovations are important requisites for enhanced productivity and generating income for the farmers. In India, farming is a way of livelihood to 65 per cent of nearly 1. 1 billion population. Our farm population is increasing annually by 1. 84 per cent. The average farm size is becoming smaller each year and the cost-riskreturn structure of farming is becoming adverse with the result that farmers are getting increasingly indebted. There is no option except to produce more food and other commodities under conditions of diminishing per capita arable land and irrigation water resource. Hence, we must harness the best in frontier technologies, thus integrate them with traditional wisdom and thereby launch an eco-technology movement.

The productivity in agricultural sectors is dependent on several bio physical and socio-economic factors. The significant biophysical factors are weather parameters, soil health, water resources, crops/ varieties and pest environments. In order to monitor the impact of weather parameters, we need to have weather forecasts and the accuracy of which to harvest the economic benefits should be given top priority. Only fifty years ago, weather forecasting was an art which was derived after interpretation of data received from land based observing stations, balloons and aircraft etc. Now, modern technology particularly computers / weather satellites / radars has resulted in enormous improvements in the accuracy of weather forecasting with the help of various coordinated meteorological observing networks.

INTRODUCTION

Inspite of recent technological developments which have helped to increase agricultural production in many countries, growth of plants and animals continue to depend to a large extent on the weather conditions. Each plant has its own climatic requirements for growth and development and any large scale deviation from it exert negative influence.

Growth of plants is most sensitive to temperature just above a threshold value and near the maximum value, where growth normally stops. Therefore, periods of extreme temperature i. e. low temperatures below the threshold value and high temperatures above the maxima are hazardous to plant development and growth. Extreme temperature conditions during cold spells cause stress and frost; high temperatures lead to heat stress, and both affect agricultural production. Snow and ice storms in late spring or early autumn are very hazardous to many temperate crops.

Similarly extremes of moisture conditions namely dry desiccating winds, drought episodes and low moisture conditions as well as very humid atmospheric conditions including wet spells tend to affect agriculture. High soil moisture situations of water logging and flooding associated with heavy rainfall and tropical storms have adverse effect on plant growth and development since they influence the rate of transpiration, leaf area expansion and ultimately plant productivity. Drastic changes in rainfall variability can have very significant impact, particularly in climatically marginal zones such as arid, semi-arid and sub-humid areas where incidence of widespread drought is frequent. Dry desiccating and strong winds reduce agricultural production as a result of very high evapotranspiration rates. It also causes mechanical damage to plant with weak stems by lodging such as the sugarcane and the banana.

INTRODUCTION

In spite of technological developments for the last few decades, Indian agriculture is still rain dependent. Extreme weather events such as drought in 2002, cold wave during 2002-03, heat wave in the year 2003, increased temperatures during rabi 2003-04 and 2004-05, deficit rainfall in many parts of the country during 2004 and excess rains in 2005 (100cm in Mumbai, floods in MP, Gujarat, Orissa, AP, Tamilnadu and Karnataka) could affect the food grain production considerably. The spatial and temporal changes in important weather parameters such as rainfall, temperature, wind, cloud cover, humidity, etc. would influence crop yields by affecting farmers’ decision in selection of cultivar, use of inputs, crop management practices, etc. These decisions significantly influence the aggregate agricultural output, which , in succession has an impact on the economy of the country as a whole. Thus, the timely and accurate weather based agro -advisories is the need of the hour for sustainable agricultural production.

Further, the quality of utility of agro-advisories can be improved through value addition to the agromet information including forecast and demonstration of economic benefits accrued due to the following of the advisories. Thus making farmers to adapt weather-based advisories for (i) Increasing the quality and quantity of produce, (ii) Efficient utilization of resources, (iii) Minimizing losses due to adverse weather, (iv) Effective utilization of favourable weather events, and (v) Reducing cost of cultivation to enhance profits.

INTRODUCTION

The discipline of Agrometeorology, an applied science is less than fifty years old. Its services are operationally used by individual farmers in developed countries, and by agricultural or development services in more than half of the countries of the world. Its contribution to agricultural production by examining forecast is sought in virtually all countries. In many countries, the respective governments have expressed the desire to use meteorological information to a much larger extent in day-to-day farm planning and operations. The climate database is used for the development of practical criteria in planning and management of irrigated and rainfed crop production system (Martin Smith, 2000).

Though a huge set of Agromet data exists in India, its utility has not been effective due to the scattered location of these data sources and the impediments for free flow of data to the users to analyze and interpret for real-time decision making in agriculture. There is also a considerable time lag between the actual observation and data availability. In view of the importance and the immediate exigency to centralize the database system for helping the researchers and planners, a central agrometeorological databank facility funded by DST from 1998 to 2003 and later by ICAR with the following objectives was established at Central Research Institute for Dryland Agriculture (ICAR), Hyderabad.