eBook Chapters

Geomorphometric analysis is the measurement of the threedimensional geometry of landforms and has traditionally been applied to watersheds, drainages, hill slopes, beaches, and other groupings of terrain features. In particular basin morphometric parameters have received a lot of attention from hydrologists and geomorphologists since watersheds (catchments) have been used for analysis of various physical ecosystem processes, including soil erosion, deposition, runoff, stream discharge, sediment yield, sedimentation of streams, irradiation by sunlight, evaporation, evapotranspiration, and nutrient distribution. The study of morphometric parameters, which include variables such as average basin slope, the basin elongation ratio, compactness ratio, basin relief and stream density. Some parameters, such as slope length or stream sinuosity, can be used to represent both basin and hill slope, or basin and stream channel properties.

The main task before geomorphologists is to use an ideal unit of the earth surface for the study of its landforms. The search for an ideal areal unit, within which the collection, processing, organization and interpretation of the data of the geometry of landform, particularly of erosional origin can be made has been the main aim of the geomorphologists right from Fennemen (1914), Horton (1932 and 1945), Strahler (1956 and 1957), Miller (1953), Chorley (1957), Schumm (1956), Shreve (1966), Singh (1981), Sarkar (1995), Schumm and Spitz (1996), Sharma and Amin (1996), Iqbaluddin et al (1997) and Raj et al (1999).

Q. 1 Which of the following is a correct match?
(A) Mole drain = pump drainage
(B) Vertical drainage = well drain age
(C) Pipe drain = well drainage
(D) Horizontal drain = bio-drainage

Drainage is the natural or artificial removal of excess water from a surface or sub-surface from an area or field or soil or greenhouse. The internal drainage of most agricultural soils in greenhouse is good enough to prevent severe waterlogging. Water logging creates anaerobic conditions that harm root growth in absence of oxygen. Soils need artificial drainage to improve production or to manage water supplies in certain conditions. Though the roots need moisture but they need oxygen too and poor drainage is g result in roots rotting and death of plants.

The irrigation water inside the greenhouse may accumulate and cause anaerobic condition. Similarly plants in pots should not accumulate water. Water should not stand in pots and beds for longer period. If it stays longer drainage is poor and needs to be corrected. It is better to have good drainage system in greenhouses or protected structures.

Besides irrigation rains water seeps in the greenhouse. The drainage system prevents running or its accumulation in low lying portion of the greenhouse. Drainage system in greenhouses is a must for avoiding damage to the crops.

A drainage system is a network of structures, channels, pipes, and natural features designed to manage and control the flow of water, primarily rainwater or surface runoff, away from inhabited areas, agricultural land, and infrastructure. The primary purpose of a drainage system is to prevent flooding, erosion, and water logging, thereby safeguarding public health and property, as well as ensuring the efficient use of land.

Surface Water Management: Surface water, which includes rainfall and other forms of precipitation, needs to be managed effectively to prevent damage to properties and the environment. Drainage systems collect this water and direct it away from vulnerable areas.

Catchments: A catchment or watershed is the area of land where rainwater collects and drains into a specific river, lake, or other water body. Understanding catchment areas is crucial in designing drainage systems because it helps determine how much water needs to be managed.

Protected cultivation of vegetable crops refers to creation of favourable environmental conditions around vegetable plants, offsetting or minimizing the detrimental effects of prevailing or expected to prevail abiotic and biotic factors. In open fields, vegetables face several abiotic and biotic stresses, resulting in lower or poor or no yield. This condition is altered by using different protected structures for cultivation and/or nursery production. Vegetables which are transplanted using seedlings should be produced by raising seedlings under protected conditions. Protected conditions ensure production of healthy seedlings. The use of healthy seedlings ensures better and higher production of vegetables both under protected conditions and open field conditions. Nursery grown in nursery trays can be transported long distances and can wait till field is ready or human resources is available for transplanting. Structures are ideal for production of plug plants/transplants in different sizes of portable trays.

Dried Fruits and Pods

The enchanting beauty and usage of fresh pods or fruits need not end up with the season. They are dried and preserved for years. A colorful array of choice dried fruits are very popular in dried arrangements. There are numerous dried fruits and pods used in potpourri and dried flower arrangements.

Dried Grasses

Grasses are easy to collect to dry and use. When the seed-heads have formed, the grass is cut off just above the soil using a sharp knife. They are allowed to lie in a thin layer in the sun for a day or two, turning them over a few times. They should not be allowed to get too damp. After they are dried they are put into a plethora of uses. Bunches of dried grasses can make a wonderful addition to any home or office.

13.1 Introduction
Drying is the process of evaporation separating a liquid from a substance or mixture of components. Either solid or solid–liquid phase describes the product to be dried. The separation follows a solid and a gas phase pattern. “Milk Product” is a product derived from milk processing that might include food additives and other substances functionally required for the milk product as approved in the laws (FSSAI Milk standards). Made to increase the storage life of the product, lower bulk so as to cut packaging and shipping costs, etc., dried milk products are created.
13.2 Dried milk
“Dried milk or milk powder is the product generated by the removal of water by heat or the equivalent means, to produce a solid containing five percent or less moisture. Dried whole milk or whole milk powder (WMP) from whole milk; and from skim milk is known as Dried Skim Milk or Skim Milk Powder (SMP), or Non-fat Dry Milk (NFDM); respectively
13.3 Whole Milk Powder
Dehydrating milk from cows, buffaloes, or a combination of both or from milk that has been standardized results in whole milk powder. Up to 0.3% of the weight of the product might be calcium chloride, citric acid, sodium citrate, and sodium salts of orthophosphoric and polyphosphoric acids; also included butylated hydroxy anisole up to 0.01% by weight. The label does not have to list these additions. Milk powder must to have a fat level at least 26.0 percent and a moisture level no more than 5.0 percent. Measured as lactic acid, its overall acidity should not be more than 1.2 percent. The Coliform count should not be more than 90 per gram; the normal plate count should be just 50,000 per gram. For roller-dried goods and spray-dried goods, the solubility index shouldn’t be higher than 15.0 or 2.0.

Flowers and plants are associated with mankind from the dawn of civilization. In the modern era these have become an integral part of human life, as love for flowers and ornamental plants is a common natural instinct in human beings. The catchy flowers glowing and glowing in all their grandeurs with simplicity always make them tempting to wish the season to continue for never ending, but it may be beyond reach of human beings. However, the answer for it could be by producing and preserving ever-lasting or long-lasting flowers and other attractive ornamental plant parts. These are now becoming favorites especially with the adventurous flower lovers across the globe. The beauty and fresh look of cut flowers and cut foliage is generally lost due to microbial activities and biochemical changes thus these are retained only for a few days even by using the best techniques of post harvest management (Datta, 1999). The charm of dried ornamental plant parts can be maintained from a few months to years with lesser cost if protected from the damage of high humidity as in dried flowers, the microbial activities in the aging process come to stand still.

The main characteristics of dried ornamentals are novelty, longevity, aesthetics, flexibility and year-round availability. The dehydrated or dried ornamentals are generally inexpensive and are sought for their everlasting and attractive appearance globally (Smith, 2000). Being largely focused on the qualities of attractive flowers, living plants and plant parts, floriculturists generally pay little attention to dried and preserved flowers and plants. Therefore, these products remained overlooked and underrated throughout the world. These are overlooked in the sense that their considerable economic importance is generally unrecognized and these are underrated in the sense that their aesthetic contribution is largely discounted. In contrast to other areas of floriculture including post-harvest management, relatively very little public funded research and development projects were undertaken on the dried flower industry across the globe (Joyce, 1998). This has slowed the pace in optimizing the dehydration technology and quality of the produces. Privately funded research and development work has sustained, but such findings are usually kept secret and limited information are available to the common man. Thus, this component of floriculture industry has remained ill defined with respect to the processes, products and organizations in the developed and developing countries. As we see in major cut flower crops, there are defined standards available for judging the quality, however these are lacking in dried ornamentals. There is an urgent need to start war- footing efforts and awareness on the dried ornamentals to attract greater public support to conduct concentrated research and development with more professionalism in the trade of these products.

Dried Petals

Many types of dried petals are used for making pot pourii eg., land lotus petals, rose petals, mahogany petals, lily petals and lotus petals. Flowers are dried for everlasting beauty. They add an elegant touch to the room and are dried for everlasting beauty. Preserving blooms is a wonderful way to preserve memories and enjoy long lasting splashes of color. Many flower parts are used in dried form. A vibrant and thrilling range of dried petals are used to embellish greeting cards, folders, books, and other personal belongings.

Driftwood is wood that has been washed onto a shore or beach of a sea or river by the action of winds, tides, waves or man. It is a form of marine debris or tide wrack.

In some waterfront areas, driftwood is a major nuisance. However, the driftwood provides shelter and food for birds, fish and other aquatic species as it floats in the ocean. Gribbles, shipworm sand bacteria decompose the wood and gradually turn it into nutrients that are reintroduced to the food web. Sometimes, the partially decomposed wood washes ashore, where it also shelters birds, plants, and other species. Driftwood can become the foundation for sand dunes.

Introduction

In the process of creating a hole in the metal surface through a drill, we use a drilling machine. We use a tapper shank and parallel shank to tie the drill to the drill machine. We can also use a drilling machine to do extra experiments i.e., tapping rimming counter shrinking and counterboring. In simple language, we also say that a, it is a machine which is wildly used over world for making a circular hole in various metal workpiece for making desired design or structure.

Crop Water Requirements

In designing an irrigation system, the primary objective is to know the water requirement of crops. Water requirement of crops are determined either by f ield cultivation or by estimation through commonly used empirical formulae such as Blaney Criddle, radiation, Penman or pan evaporation method.

Definitions

Crop water requirement or evapotranspiration (ETcrop ): It may be defined as the rate of evapotranspiration of a disease free crop growing in a field of not less than one hectare under adequate fertility and water supply so that full productive potential can be achieved in prevailing environment. Evapotranspiration requirement of a crop refers the ETcrop and expressed in mm/day.

Reference crop evapotranspiration (ET0 ): It is the rate of evapotranspiration from an extended surface of 8 to 15cm tall green grass of uniform height, actively growing, completely shading the ground and not short of water. ET0 may be computed by using the empirical formulae and meteorological data for the specific period.

Introduction

Drip irrigation is an efficient method of application of water at the plant bottom at a rate nearly equal to the consumptive use rate of the plant, thereby minimizing the conventional water losses like percolation, runoff and evaporation from soil. It is a process of slow application of water on, above or beneath the soil by the surface, sub-surface, bubbler, and spray or pulse system. Fertilizer can also be applied with the drip water. Emitters or applicators are placed closed to the plants and used to spray water in the form of drops, tiny streams or miniature spray. In the drip system water applied from the point source advances in all direction in the soil outward from the source. Drip irrigation is essentially a low rate, low pressure, frequent and long duration application of water in plants root zone area.

Drip irrigation is also called as localized irrigation, trickle irrigation, daily f low irrigation, diurnal irrigation, drop irrigation, sip irrigation, and micro irrigation. A particular name is being popularized in any area depending on the choice of the people of that area. The International Commission for Irrigation and Drainage (ICID) has recommended the term micro-irrigation while the American Society of Agricultural Engineers (ASAE) has preferred drip irrigation. In India it is told as drip irrigation.

Micro irrigation normally called as drip irrigation was introduced in early seventies. Drip irrigation is one of the advanced methods of irrigation, by which water can be supplied directly into the root zone of the soil to achieve considerable saving of water through high water use efficiency, compared to surface irrigation method where water use efficiency is low due to losses in the water distribution system in the field. In micro irrigation method, water supplied at slow rate that is 1.0-2.0 kg/sq cm to the root zone of an individual plant through lets called emitters or drippers fitted with laterals pipes and filters at pump side. The success of micro irrigation is proven and efforts are being made in promoting the same extensively among the farmers in arid areas.

The hot arid regions of India are spread over about 31.7 million ha area mainly in the States of Rajasthan, Gujarat, Andhra Pradesh, Punjab and Haryana, which inhabit on an average 61 persons per square km making up a population of nearly 20 million peoples. The Indian arid zone is characterized by high temperature and low and variable precipitation which limit the scope for high horticultural productivity. However, these conditions greatly favour development of high quality production in number of fruits such as date palm, ber, pomegranate, citrus, aonla, bael, grapes and, guava. The optimized technologies and inputs could increase the existing low productivity. It is now realized that there is a limited scope for quantum jump in fruit and vegetable production in the traditional production areas. The amelioration of the extreme conditions is also considered vital for life support to the inhabitants of this area. The recent awareness regarding the potential of these ecologically fragile lands for production of quality horticultural produce has not only opened up scope for providing economic sustenance for the people of this region, but also for bringing new areas to increase production through horticulture.

The hot arid regions of India are spread over an area of about 31.7 million ha, mainly in the states of Rajasthan, Gujarat, Andhra Pradesh, Punjab, and Haryana, which inhabit an average of 61 people per square km, making up a population of nearly 20 million people. The Indian arid zone is characterized by high temperature and low and variable precipitation, which limit the scope for high horticultural productivity. However, these conditions greatly favor the development of high-quality production in a number of fruits, such as date palm, ber, pomegranate, citrus, aonla, bael, grapes, and guava. The optimized technologies and inputs could increase the existing low productivity. It is now realized that there is a limited scope for a quantum jump in fruit and vegetable production in the traditional production areas. The amelioration of the extreme conditions is also considered vital for the life support of the inhabitants of this area. The recent awareness regarding the potential of these ecologically fragile lands for the production of quality horticultural produce has not only opened up the scope for providing economic sustenance for the people of this region but also for bringing new areas to increase production through horticulture. The scope of expanding water supplies through the development of water resources is very limited since suitable dam sites are fewer, development costs are prohibited, and environmental concerns are too strong. This has led to the realization that saving on the use of water is an option for expanding the water supply.

2.1 Introduction

Water is the most precious gift of the nature and it is also the most crucial element for sustainability of the life in the earth. India is the largest user of freshwater in the world. India’s total water consumption alone is the higher than any other continents. The Agricultural sector is the largest consumer of water followed by the domestic sector and the industrial sector. The role of irrigation water as one of the most essential inputs for crop cultivation can’t be denied. As a traditional productive input, it ensures production by acting as an agent of insurance against inadequate and inconsistent monsoon. Ultimately the outcome provides agricultural production stability. Thus, irrigation is of prime importance in cultivation of vegetable crops as it ensures favourable water balance within the root zone in addition to natural precipitation. It fulfils the crop- water demand and improves the crop production and effectiveness of other agricultural inputs. It is also an important limiting factor of crop yield, because of its association with several factors of plant environment, which directly influence the crop growth and development (Yaghi et al., 2013). The various irrigation methods under different system of irrigation differ with regard to extent of control, timeliness and adequacy of supply of irrigation water for crop cultivation. Consequently, the economic benefits and the costs due to these irrigation methods vary among different irrigation systems. The dominant method of irrigation practiced in large parts of the country is surface irrigation (basin, border and furrow) where the entire soil surface is almost f looded without considering the actual consumptive requirements of the crops. Frequent over or under irrigation create the problems of water stress or water logging leading to reduced irrigation efficiency (less than 30%).

21.1 INTRODUCTION

High population pressure has forced us to plough 46 per cent of our country area for food production. The present productivity is 12.36 tonnes/ha of fruits needs to be raised to 40.0 tonnes/ha by using N : P₂O₅: K₂O with other inputs, since recommended ratio is 0.75:0.50:1.00 only.

Since cost of the inputs like fertilizers and manures are very high, hence, efficient nutrient management is essential for sustainable fruit production and protection of the environment from different types of hazards occurring due to misuse of costly fertilizers.

The soils of India and especially of arid and semi-arid regions are impoverished to plant nutrients. Considering economy, energy and environment, it is imperative to use nutrients effectively by adopting the appropriate doses proper, placement and correct timings of application and to sustain the available nutrients in soil at the optimum level.

Wound healing is defined as any breach in the continuity of skin. Regenerative pharmacology aims to develop new therapeutic module to hasten the healing. Present study was aimed to evaluate the wound healing efficacy of goat milk based ointment vis a vis its molecular pharmacodynamics in full thickness excisional rat model. 96 healthy male Wistar rats were equally and randomly divided into four groups i.e. group I served as Healthy control/Sham Operated, group II served as silver sulphadiazine treated group and group III and IV served as group treated with 0.5 % and 1% goat milk based ointment, respectively. Square shaped wound of ≈ 2×2 cm2 (400 mm2) was surgically and aseptically created on the back of animals till the depth of panniculus carnosus. Animals were examined routinely till 21 day of the experimental study and healing potential of goat milk based ointment was ascertained by planimetric analysis viz. digital photography, wound area measurement, wound contraction percentage and biochemical assay using hydroxyproline, total protein and DNA content at different intervals i.e. on days 3,7,14 and 21 of the study.

In 1920, a 30-year-old Czech writer Karel Èapek, wrote a play called “R.U.R.” (Rossumovi Univerzální Roboti or Rossum’s Universal Robots). For this dystopian work about a bad day at a factory populated with sentient androids, Èapek called the androids “roboti”, as suggested byhis brother Josef, a painter and writer. It was premiered in Prague on 25^th January, 1921.

Èapek was admired for his opinions:

My dear Miss Glory, Robots are not people. They are mechanically more perfect than we are, they have an astounding intellectual capacity, but they have no soul.

But surprisingly he was keen on gardening!

Drivers
• Unique aspects of the local climate and soil.
• Availability of resources and land labor.
• The current level of resource use.
• Economics of the proposed integrated farming.
• Farmer’s management skills

4.2.1. Gear boxes

It is a unit fitted after the clutch. Forms a part of transmission and provides speed and torque conversions from a rotating power source to another device using gear ratios. Its primary function is to change the speed of the tractor to cater to varying field, road and load condition. It also helps in reversing the tractor.

Gears are usually made of alloy steel. Since the tractor has to transmit heavy torque all the time, the best quality lubricants, free from sediments, grit, alkali and moisture, are used for lubrication. SAE 90 oil is generally recommended for gear box.

The description about gear boxes stated below pertains to major tractors manufactured in India. The number of teeth in each of the gear and the engagement between gears of the main shaft and the corresponding gear on the counter/lay shaft also change in different tractors evolved over a period of time. Hence, information hosted in this section is only indicative.

Sambit Sharma, Chairman, CTN Limited (CTNL) received a letter from the Chairperson of 3^rd Pay Revision Committee (PRC) for Public Sector Undertaking (PSU) of India. The letter inter alia sought feedback on existing Performance Management System (PMS) at CTNL and suggestion for its continuity or modification, if any. In past also, CTNL's suggestions on various human resources (HR) matters had been valued by the Committee and many of those suggestions were retained in their final recommendations to the Government of India. Mr. Sharma, off late, had heard many stories, both positive as well as negative, about the PMS within CTNL and was therefore contemplating to thoroughly review the system. He marked the letter to Ratish Agarwal, Director (HR), CTNL to take necessary action.

This chapter traces the history of the electric quadcopter commonly known as the drone, prior to its use in agriculture.

As long ago as 1493, the versatile Italian Leonardo de Vinci, painter, sculptor, machine designer often inspired by his observations of Nature, made a sketch in one of his little notebooks of a screw-like machine next to which he wrote in his mirror-handwriting:

If this instrument made with a screw be well made – that is to say, made of linen of which the pores are stopped up with starch and be turned swiftly, the said screw will make its spiral in the air and it will rise high.¹

Four centuries later, in 1863, the Viscount Gustave du Ponton d’Amécourt, President of The Society for the Encouragement of Aerial Locomotion by Means of Heavier than Air Machines, published a forty-page monograph in Paris, entitled “The Conquest of the air by propeller. Account of a new system of aviation.” In this he took the Greek words helico and pteron, meaning “spiral” and “wing”, and combined them into the word hélicoptère (helicopter). D’Amécourt and his friends were among those very few who were passionately convinced that the future of flying was with heavier-than-air machines. To prove their point, having built a fragile flying machine model driven by clockwork springs, they watched it ascend vertically for a few seconds to a height of less than 3 metres (10 feet), only to crash back to the ground.

Aerial photography is objective of getting panoramic view of earth surface to analyze the features of earth and their interrelation at particular time period which may be changed in further events. In this concerned, the observation may play a vital role in achieving the goals of photography. Undoubtedly it is widely used in social function and so on, but still awaited for scientific or research use. Drone can measure the geometry of ground surface at lower altitude with more accuracy in the form of visual feature in natural colour. flight height of drone mainly limits the large area coverage due to lower flying and drone can work perfectly at low altitude planning with good quality feature/photography.

OVERVIEW OF UNMANNED AERIAL VEHICLE (UAV) TECHNOLOGY
Agricultural drone technology employs drones equipped with cameras and sensors to assist farmers in monitoring crops, applying pesticides, and analyzing soil conditions. This technology assists farmers in making informed decisions, enhancing yields, and minimizing chemical application.
A drone is fundamentally a flying robot that can be operated remotely or autonomously through software-driven flight plans within its embedded systems, which integrate with onboard sensors and a Global Positioning System (GPS).
Drones are remotely operated or autonomous aircraft engineered to function without a pilot on board. They are also referred to as Unmanned Aerial Vehicles (UAVs). They has the capability to function alone or be managed by human operators.
• They have gained significant popularity in recent years owing to their extensive range of applications and uses. Drones are available in a range of sizes and configurations, from compact portable models to larger variants. They possess an array of equipment that enables optimal functionality.
• The fundamental components of a drone consist of motors, propellers, flight controllers, batteries, and remote control systems. The motor and propeller are essential for generating push to elevate the drone from the ground, whilst the flight controller functions as the drone’s brain, responsible for data processing and movement regulation.
• The battery energizes the drone’s electronic components, while the remote control systems enable the operator to maneuver the drone. The drone functions by an integration of electronic components and software algorithms.

Drone

Drones are one of the most innovative new technologies to emerge from the fourth Industrial Revolution. Indian farms may be significantly impacted by drone use in pesticide spraying, hence government cooperation is required for allowing supporting legislative environment.

Advantages

The following are the key advantages of using drones for pesticide spraying:

• Improved agrochemical application efficiency and accuracy. Crop protection products (CPP) are not wasted as a result, which improves pest management and crop output.

• Considerable decrease in operator exposure risk during spray operations.

• Drone-assisted spraying has a field capacity that is nearly 20 times greater in comparison to manual spraying.

• Lower water consumption.

EAAMs (Electric Agricultural Aerial Machines) have emerged from drones used for both aerial filming, as toys and even as racing units. A Price water house Coopers’ study revealed that the global market for drone-powered business solutions was valued at $127.3 billion in 2016. For agriculture, prospective drone applications in global projects were valued at $32.4 billion. Stelios Kotakis and colleagues at market research firm IHS Markit projected that there would be around 400,000 shipments of drones to firms in the agriculture and forestry sectors in 2017. The Food and Agriculture Organization (FAO) of the United Nations projects that by 2050 humanity’s ranks will likely have grown to nearly 10 billion people. Farmers will need to produce more with less, while preserving our environment for future generations. And society has a duty to help them achieve this. Although agriculture is perceived as a traditional economic sector, precision agriculture technologies have already boosted crop yields significantly in the last decades. The same study forecast that agricultural consumption would increase by 69% from 2010 to 2050.

Drought

There is no universally accepted definition of drought. Early workers defined drought as prolonged period without rainfall. Drought is a situation when the actual seasonal rainfall is deficient by more than twice the mean deviation. American Meteorological Society defined drought as a period of abnormally dry weather, sufficiently prolonged for lack of water to cause a severe hydrological imbalance in the area affected.

Prolonged deficiency of soil moisture adversely affected crop growth indicating incidence of agriculture drought. It is the result of imbalance between soil moisture and evapotranspiration needs of an area over a fairly long period as to cause damage to standing crops and to reduce the yields.

Importance

Drought is a climatic anomaly characterized by deficient supply of moisture, which may result from sub-normal, untimely and unevenly distributed rainfall. Among the various hazards of nature, drought is one of the major disasters because it brings innumerable miseries to the mankind. Almost every year some part or the other of the country suffers from such calamities. Drought is a recurring phenomena and its occurrence cannot be avoided. However, its impact can be minimized through application of science and technology by developing drought management plans.

The world’s drylands include hyper-arid, arid, semi-arid and dry sub-humid areas where rainfall is highly scanty and variable. Droughts are common in areas / zones where water is the principal limiting factor for agriculture (https:// www.fao.org/3/t0122e/t0122e03.htm) . Dryland soils are characterized by low levels of moisture, organic matter, and biological activity, consequently such soils are very poor in fertility devoid of plant nutrients. When, these soils suffer further degradation in fertility, resulting in erosion, desertification, and salinization when crops are grown on such soils inappropriately without any scientific basis. However, the major factor limiting agricultural production on drylands is the lack of adequate moisture for crop growth or drought.

Low rainfall or failure of monsoon rains is a recurring feature in India. This has been responsible for drought and famines. The word drought, generally, denotes scarcity of water in a region. Though, aridity and drought are due to insufficient water, aridity is a permanent climatic feature and is the culmination of a number of long term process. However, drought is a temporary condition that occurs for a short period due to deficient precipitation for vegetation, river flow, water supply and human consumption. Drought is due to anomaly in atmospheric circulation.

Introduction

The study of abiotic stresses in plants has advanced significantly in recent years. However, the majority of experiments testing the response of plants to changes in environmental conditions have focused on a single stress treatment applied to plants under controlled conditions. In contrast, in the field, a number of different stresses can occur simultaneously. These may include conditions such as high irradiance, low water availability, extreme temperature, or high salinity and may alter plant metabolism in a novel manner that may be different from that caused by each of the different stresses applied individually. The response of plants to abiotic stresses in the field may therefore be very different from that tested in the laboratory (Cushman and Bohnert, 2000).

Drought is a situation when the demand for water is much greater than the availability of water. Drought is a creeping phenomenon and it is experienced only after it has set in. The scarcity of water compared to demand will have greater impact on every activity of human life including failure of crops, food shortages, decline in ground water table, drying tanks, lakes or reservoirs, acute shortage of drinking water for humans and livestock shortage for cattle etc.

Drought will have very serious impact on economy of households as well as that of nation. There are five different types of droughts depending upon the nature of shortage of water

10.1 Meteorological Drought

Meteorological drought occurs when the water received through rainfall during a given period is much less than long period average rainfall of the area. The meteorological drought is associated with either failure of rain or due to long gap between the successive rainfall events. In India, meteorological drought occurs due to failure of south west monsoon or long breaks in south west monsoon rainfall. In Tamil Nadu the drought occurs due to failure of north east monsoon rainfall during months of October to December.

Introduction

Drought is defined as “when a region receives below average precipitation,  resulting in prolonged shortages in its water supply, whether surface  or ground water or atmospheric. It can have a substantial impact on the  ecosystem and agriculture of the affected region.” When drought arises in  a particular area, obviously it affects the crop and livestock production. In  order to reduce the effect of drought on farm productivity and to stabilize farm  income, farmers have to take some systematic measures, and such measures  are referred to as drought coping mechanisms. The objective of the study was  to identify the determinants of the adoption of drought-coping mechanisms to  balance and stabilize the farm income of the stakeholders. The study also helps  to know how to mitigate the effect of drought on farmer’s livelihoods.

The existing literature on the adoption of drought coping mechanisms is  quite meager. Akwango et al., (2016), Chandan Kumar Jha et al., (2017),  Emmanuella Ellis (2017), Ronald Twongyirwe et al., (2019) assessed the adoption strategies by considering multinomial logistic regression and the  results state that the use of different tree planting, crop varieties, soil and water  conservation, early and late planting, and furrow irrigation. The data related to  the adoption of any agriculture technology have qualitative response variables  with two or more categories. Most of the studies used qualitative response  models such as the logit model, probit model, and multivariate techniques like  discriminant analysis to measure the farmer’s perception toward the adoption  of any agriculture technology. In this study, we chose machine learning models  such as Decision tree, to assess the classification ability and to determine the  factors influencing adoption.

5.1 Introduction

Out of the many climatic events that influence the earth’s environmental fabric, drought is perhaps the one that is most linked with desertification. Drought is a natural hazard originating from a deficiency of precipitation that results in a water shortage for some activities or some groups and is often associated with other climatic factors (such as high temperatures, high winds and low relative humidity) that can aggravate the severity of the event. Drought differs from aridity in that the latter is restricted to low rainfall regions and is a permanent feature of the climate. Drought occurrences are common in virtually all climatic regimes.

Widespread and severe drought conditions in Asia, Latin America and the Caribbean in 2000 have raised serious concerns about the continuing vulnerability of the world community to extended periods of droughts and water shortages. In 2000, major droughts affected much of south-eastern Europe, the Middle East, and the area through central Asia to northern China. Especially hard hit was Afghanistan, Bulgaria, Iraq and the Islamic Republic of Iran and parts of China. In North America, months of above-average temperature coincided with below-normal precipitation through northern Mexico and much of the southern and western regions of the USA, leading to one of the worst wildfires in the past 50 years.

By August 2001, much of Western Asia, Central Asia, and the Middle East was suffering the third year of a continuing drought that severely reduced many countries’ crop yields. The countries most affected were Afghanistan, India, Islamic Republic of Iran, Pakistan, and Tajikistan.

1. Introduction
Drought’ which apparently means lack of water, is one of most vulnerable natural hazards. It alone causes a huge crop loss annually. But history says it not only affects crop but destroys human lives.in the year 1972 almost 600000 people died due to starvation caused by huge drought in Northern India. In simple language drought means shortage of water mainly caused by abnormal climatic condition and damaging to the environment. Ideally there is no such proper definition of drought because it should be region specific and circumstances specific. A per McMahon and Diaz Arenas (1982) define drought as “a period of abnormally dry weather sufficiently prolonged for the lack of precipitation to cause a serious hydrological imbalance, carrying connotations of a moisture deficiency with respect to man’s usage of water”. Apart from these several general definitions have been provided by many authors. Beran and Rodier (1985) gave a definition based on hydrological aspect of drought that, ‘The chief characteristic of a drought is a decrease of water availability in a particular period and over a particular area’. India meteorological department (IMD) has defined drought as a situation in a subdivision in a year when the actual rainfall is less than 75% of the normal annual rainfall. Basically, to define drought the impact on environment and society and their complex interaction must be considered. Drought is defined as a state of total water capacity being within the range of 12-20% for a period of 16 days and can be distinguished from water deficit, which is the state of water capacity falling below 30%. Drought affects crop development, production, productivity and quality and on other hand soil physical, chemical and biological properties.
2. Classification of Drought
As per the hydrological point of view drought can be classified into different Categories: i) On the basis of source from which water is available: -a. Meteorological Drought b. Hydrological drought c. Agricultural Drought. ii) On the basis of time of occurrence: - a. permanent drought area b. Seasonal Drought Area contingent drought. iii) On the basis of medium: - a. soil drought atmospheric drought.

There are reports in financial newspapers that the ongoing (2010) drought affecting nearly 200 districts in the country may not have much effect on GDP, since the farmers in the drought-affected areas contribute hardly 3 per cent to GDP.  It is sad that such a measure of the impact of drought on the lives and livelihoods of millions of rural families is even considered. It is this mindset, typical of the growing insensitivity to human suffering in our country, that is responsible for India being the home for the largest number of undernourished and malnourished children, women and men in the world.  No wonder we are finding it difficult to achieve the first among the UN Millennium Development Goals, namely, reducing hunger and poverty by half by 2015.  Unless we realise that agriculture in India is not just a food- producing machine, but is the backbone of the livelihood of over 60 per cent of our population, rural deprivation and suffering will not only continue to persist, but will get worse, leading to severe social unrest.

Improving water use efficiency or enhancing agricultural water productivity is a critical response to growing water scarcity, including the need to leave enough water in rivers and lakes to sustain ecosystems and to meet the growing demands of cities and industries. Rainfall is the main source of water for the existence of life on the earth. Timely onset of rainfall and its distribution during the crop growing season determine the success of agriculture and food production. Unfortunately, the human life has hardly any control over nature and prevailance of delayed onset of monsoon and dryspells during different stages of crop growth are commonly observed in the dryland agriculture. Drought is a weather-related natural disaster which makes greater impact on food production and it reduces life expectancy and the economic performance of large regions or entire countries. Drought is a recurrent feature of the climate. It occurs in virtually all climatic zones, and its characteristics vary significantly among regions. Drought differs from aridity in that drought is temporary; aridity is permanent characteristic of regions with low rainfall. Drought is related to a deficiency of precipitation over an extended period of time, usually for a season or more. This deficiency results in a water shortage for some activity, group or environmental sector. Drought is also related to the timing of precipitation. Other climatic factors such as high temperature, high wind and low relative humidity are often associated with drought.

Drought, a recurring and often devastating feature of climate variability, presents a unique challenge due to its slow onset, complex nature, and farreaching consequences. Unlike hazards with clear event boundaries, drought manifests across diverse spatial and temporal scales and impacts nearly every facet of the environment and human activity. Effectively understanding and managing this phenomenon necessitates an equally comprehensive approach: drought monitoring. This chapter introduces the essential concepts and methodologies underpinning this critical field, highlighting the remarkable breadth required to capture the full picture of drought conditions. • The scope of drought monitoring is inherently vast. Geographically, it spans from tracking localized water stress affecting a single farm or watershed to assessing conditions across entire regions, nations, and continents. Temporally, monitoring efforts must consider short-term deficits unfolding over weeks or months (critical for agriculture) as well as long-term hydrological imbalances developing over seasons, years, or even decades (impacting reservoirs and groundwater). Understanding current conditions crucially relies on comparing them against a deep historical context, requiring decades of baseline data

Drought is a complex and multifaceted issue that affects various aspects of the environment, economy, and society. Its far-reaching consequences underscore the need for a comprehensive and collective approach to mitigate its impacts. 2.1 Drought Prone Area Delineation Drought-prone area delineation involves using scientific criteria like low and erratic rainfall, groundwater potential and agricultural indicators to identify regions susceptible to drought. Modern methods use GIS (Geographic Information Systems) to integrate data from satellite imagery, weather patterns, soil conditions, and vegetation to precisely map drought-vulnerable zones. This spatial analysis allows for targeted interventions such as improved water management techniques and sustainable agricultural practices in the most affected areas. Here are some additional details on the universal nature of drought and the benefits of a global response:

Introduction

Drought is the most common adverse environmental factor which limits crop production in different parts of the world. Often drought is accompanied by relatively high temperatures, which promote evapotranspiration, and hence could accentuate the effects of drought and thereby further reduce crop yields. Since these events occur more frequently in tropical and semitropical regions where most of the developing countries are situated, droughts are often associated with food shortages and an overall setback to developmental activities. Therefore, raising of drought-resistant crops is common sense to achieve stability in production and to enhance the possibility of self-suficiency in food. Consequently, breeding for drought resistance is a major objective of many research programmes in the international and national institutions. This has been so for the past several decades. But, it is disappointing that, there has not been any measurable success in these programmes compared with the success achieved in breeding for yield; or breeding for disease resistance or breeding for quality attributes. In fact, this was amply expressed by Arnon (1980) when he stated “Breeding for drought resistance has been a consistent theme for as long as I remember and probably the greatest source of wasted breeding efforts in the whole field of plant breeding.” However, the fact remains that we do hear of drought resistant varieties in many crops. For example, C-306 in wheat, Lalnakanda in rice and M 35-1 in Sorghum are some of the better known examples in India. It is also claimed that a large number of cultures among the Assam Rice Collection exhibit a considerably high degree of drought tolerance. Many land races and wild relatives of several crop species are said to contain drought resistant traits, which could be profitably utilised in breeding programmes. This situation is not unique to India alone but is a common experience in different parts of the world. However, to afirm a conviction a short questionnaire to assess the current state-of-art on breeding for drought resistance was distributed to 75 distinguished plant breeders and plant physiologists all over the world. The questionnaire and a summary based on the responses is as follows: