eChapters

Air Constantly moves from place to place due to pressure differences which are caused by difference in temperature.

Wind has been defined as air in horizontal motion. According to Byers, “The wind is simply air in motion, usually measured only in its horizontal component”. According to Trewaitha, “Wind is simply air moving in a direction which is essentially parallel with the Earth’s surface.

There are two types of movement of wind in the atmosphere.

1. Horizontal movement

2. Vertical movement (Currents)

The primary wind circulation in Northern and Southern hemispheres is seen in figure on page 51.

Cloud has been defined as a visible aggregation of minute water droplets and / or ice particles in the air, usually above the ground level.

CLASSIFICATION OF CLOUDS

Though confusion apparently arises from the number of kinds or species, the genera seems reasonably clear out, if we are able to recognize their main characteristics.

Clouds are usually classified according to their height and appearance. For convenience, we list them in descending order. High clouds, middle clouds and low clouds are some forms do not fit in any of these categories. But fortunately their particular characteristics make them easily identifiable as vertical development clouds. We must exercise some caution in studying on height. There is some seasonal as well as latitudinal variation and there is some overlapping from time to time. However, the appearance of clouds is quite distinctive for each height category.

Abstract

Cultivation of cash crops of good quality potent to give good economic returns depends largely upon adoption of modern practices in agriculture. The region under test consideration is completely irrigated and cultivates mostly the crops of grapes and sugarcane. A field testing that was carried out for the pumps used by local farmers, revealed glaring inefficiency in pump operation. This is attributed to numerous reasons, the standout of them-being improper pump selection and deviation from operating point. Survey of the farming pattern helped to establish nexus between the energy usages per acre for the two crops. Carbon Footprint was determined for the electricity utilized in these farms. Adoption of selection methodologies and efficient practices would lead to considerable saving in electrical power consumption. The impact of adoption of efficient practices was therefore quantified.

Keywords: Agriculture, Carbon Footprint, Pumps

Abstract

A study on colloids in groundwater and its relationship with the geochemical parameters is reasonably essential because of its facilitating nature to transport radionuclides in groundwater. Colloid sampling has been carried out in the coastal aquifers of southeast coast of India. Two different bore wells were selected based on the distance from the coast to collect groundwater samples. On the basis of the result achieved from this study, a reliable representation is emerging. The values of pH and EC are governed by the different size fraction of colloids. In this study, the relation between different size fractions of groundwater colloids and its pH, TDS and EC were carried out. These parameters were analyzed in the lab and its influence with four fractions of colloid like 1.2, 0.8, 0.45 and 0.22 µm have been discovered by smooth scatter plot. The accumulation of particles weighting by normal weighing instrument. There is an higher accumulation of particles found in Kalpakkam than Anupuram in all the size fractions. For separation of particles high frequency pressure was used by ultrasonic cleaner had been carried out. This method is very simple and more reasonable than any other methods.

In his classic book ‘The Ascent of Man’, Bronowski has written, “When I was a young man, we all thought that mastery came from man’s domination of his physical environment. Now we have learned that real mastery comes from understanding and moulding the living environment.” Our Biosphere, the living environment that supports us all, has problems and we humans are mainly responsible. We do not live ‘gently’ on the earth. The seven billion of us require air, water, food, energy, housing and amenities and we have developed the earth to provide them and have also created problems. That the problems exist are serious is the bad news. That we are recognizing them and that man has shown ability to organize and grow in ascending order from time to time is the good news.

Reducing the input costs in farming, especially agrochemicals and improving the yields of farm products in environmentally sustainable way, is one of the most important challenges. World over, the understanding of alternative eco-friendly inputs and intelligent integration of such products with the farming practices are the areas which need to be emphasized, understood and demonstrated. Our experience of working with farmers in different regions has convinced us that they all are looking for alternative, eco-friendly and cost effective inputs and the only way to convince them is practical demonstrations. 
Eco safe farming is a global challenge and needs combined efforts of NGO_s and farmers bodies, private and public sector industries and scientists in the institutions and universities. There are many challenges and many success stories and some typical once are listed here.

Indian Government has several developmental programmes to promote agriculture and rural sector. It includes Drought Prone Area Program, Antodaya Programme, Integrated Rural Development Programme, Hill Area Development Programme, Desert Development Programme, Intensive Jawahar Rojgar Yojna and Employment Assurance Scheme, Indira AwaasYojna, Integrated Waste Land Development Programme, National Food Security Mission, National Horticulture Mission, etc. Mahatma Gandhi National Rural Employment Guarantee Scheme (MGNREGS) has the main focus to provide guaranteed employment for 100 days in a year to every rural household. Since 2014, the Swachh Bharat Abhiyan has been a major initiative by the Government of India.

Normally we associate our agriculture and food supply with farms and villages. The new trends of greener cities and urban and peri urban horticulture (UPH) are emerging very fast. Towns and cities in the world’s developing countries are growing at great speed. Ten years ago, an estimated 40 percent of the developing world’s population or 2 billion people lived in urban areas. Since then, their numbers have expanded twice as fast as total population growth, to more than 2.5 billion. By 2025, more than half the developing world’s population of 3.5 billion will be urban. Again most of the world’s fastest growing cities are in Asia and Africa with young population.

Since many decades environmentalists have warned of perils of chemicalised sports grounds, golf courses and cricket fields. They warn that our health is inextricably linked to the widespread use of toxic chemicals and also complain about the non-availability of safe alternatives.
Eco-sustainable sports fields must use the methods : 
    ·    That do not pollute
    ·    That are environment-friendly and effective
    ·    That economize on the use of water and energy

The Late Dr. APJ Abdul Kalam is described as a great patriot, visionary leader and the 11th President of India ( 2002 – 2007 ). The country would have celebrated his 84th birth day on 15th October 2015. To many like me, he was the most ideal role model that the youth of India needed, in recent time. He emerged as a complete human-being who touched the lives of people.

My first meeting with him was when he visited IPCL in eighties - as the DRDO Chief to discuss about Carbon Fiber and Composites. I was heading GSFC’s R&D Centre and other facilities like engineering plastic Nylon – 6 and their Composites and hence was invited to join the discussions. That interaction left a strong impression in my mind. Later when I became Vice Chancellor of Gujarat Agricultural University, I had many more opportunities to meet him and was often surprised at his deep rooted interest and knowledge in every sphere of Science & Technology. Subsequently, to my delight, I received an invitation from his office on the eve of 26th January evening - at home with the President and later was given more time for a one-to-one meeting the next day. Walking across the corridors of the Rashtrapathi Bhavan, the atmosphere looked rather formal and uneasy for me, but, as I was ushered into his room, I saw Dr. Kalam wearing his favourite blue shirt and smiling. He moved forward and greeted me with the same friendliness and warmth. As we started talking about Agriculture scenario, the work I was planning and the future prospects, I marveled at his understanding and insight and left the room truly inspired. 

Groundwater is a precious renewable resource which gets replenishment from the precipitation. Total water resources of the world are estimated at 1.37 x 10⁸ million ha-m. Of these, about 97.2% is salt water, mainly in oceans, and only 2.8% is available as fresh water. And, out of this 2.8%, about 2.2% is available as surface water (2.1% is fresh water in glaciers and icecaps, 0.1% is available in lakes and reservoirs, 0.0001% in streams) and 0.6% is available as groundwater. Only 50% of groundwater resource is economically extracted with available technology. Presently, 1.3 x 10⁴ million ha-m fresh water in reservoirs and 41.1x10⁴ million ha-m groundwater is theoretically available to provide usable water for drinking, domestic use, irrigation, etc., to mankind. Groundwater is the largest source of fresh water excluding the polar icecaps and glaciers. The amount of groundwater within 800 m from the ground surface is over 30 times the amount in all fresh water lakes and reservoirs, and about 3000 times the amount in stream channels, at any one time.

Introduction

Salinity in India is a major issue affecting the sustainability of irrigated as well as non-irrigated areas particularly in the states of Rajasthan, Gujarat, Haryana, Uttar Pradesh, West Bengal and Orissa. Salt affected soils are unproductive unless excess salts are reduced or removed. These soils occur most extensively in arid and semi-arid climates, but these soils are also found in coastal sea areas where soils are unundated by ocean or sea water. Soils are said to be saline if they contain an excess of soluble salts and sodic or alkali if they contain an excess of sodium salts. Again soils are said to be saline-sodic or saline-alkali if they contain appreciable amounts of both soluble salts and sodium. The impact of salinity manifests itself in several ways. As the salinity increases, not only does the productivity decline but sensitive crops also go out of cultivation and are replaced by salt-tolerant, low value crops and other plant species.

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.

Agriculture is world’s single largest employer and probably the most weather dependent of all human activities.  Climate and its variability have been and continue to be, the principal source of fluctuations in global food production. Throughout history, extreames of heat and cold, droughts and floods, and various form of violent weather have wretched havoc on the global agricultural production. With the unprecedented increase in population over past few decades, clearly the mankind faces undertaking task to ensure food and nutritional security for all, considering reduced per capita land, reduced availability of water, depleting biodiversity and need to preserve ecology and environment. In India, of the total geographical area of 328 m ha, about 175 m ha (53 % of total) are categorized as degraded land, of which 150 m ha are subjected to serious water and wind erosion (Singh et al. 1981). Crops are sown in about 180 m ha annually. Since it seems very much impossible to bring more area under cultivation we need to achieve greater efficiency in the natural resources use while conserving the environment by placing greater emphasis on understanding and exploiting climatic resources for the benefits of agriculture.

Abiotic Environment

The physical or abiotic environment includes all those physical and non-living chemical aspects, which exert an influence on living organisms. The abiotic components are soil, water, air and energy from various sources. These provide both habitation and raw material for the synthesis of organic food.

6.1 Biodiversity

Biodiversity means biological diversity. It measures the variety of the earth’s animal, plant and microbial species; of genetic difference within species and of the ecosystems that support the species in its widest. Biodiversity is virtually synonymous with “life on earth”, this word was coined in 1985. Biodiversity is the degree of variety in nature and not nature itself.

To a layman, wasteland is a piece of land, which is lying uninhabited or uncultivated. These lands are also commonly perceived to produce much less than their potential. Depleted of the green cover and productivity, such lands are often in a critical condition. Broadly, wastelands may be defined as land where the production of biomass is less than its optimum ‘productivity. Wasteland also refers to lands, which are economically unproductive, ecologically unstable and subject to environmental deterioration.

In November 1992 a document entitled Warning to Humanity was released, signed by 1500 scientists from around the world, including 99 Nobel laureates, and the Director General of the United Nations Educational, Scientific and Cultural Organization (UNESCO). The document stated that “human beings and the natural world are on a collision course,” which “may so alter the living world that it will be unable to sustain life in the manner that we know.”

1. Introduction

Cold-Arid areas are unique eco-systems lying in the north-western Himalaya. The Himalayan mountain ranges can broadly be grouped in two categories 1) the Himalayan ranges extending to the south of the main range including the greater Himalaya and 2) the trans-Himalayan ranges to the north of it. The cold-arid areas are situated in the Trans-Himalayan ranges which comprise of the Zanskar Range, the Ladakh Range and the Karakoram Range. The Ladakh region is situated in the rain shadow of the Himalaya and is dry and arid. To its south lie the Himalayan mountains, in west lies the Kashmir, in east lies the Tibet and the northern boundaries are flanked by the Karakoram ranges.

Abstract

Soils of various depth ranges were identified at the experimental farm of Central Arid Zone Research Institute, Regional Research Station, Kukma-Bhuj, Gujarat. Different depth range of soils included in this study were shallow soil (effective soil depth <15 cm), moderately deep soil (effective soil depth15- 25 cm), deep (effective soil depth 25-70 cm), and very deep (effective soil depth 70 to >1m). The soils are developed from calcareous and ferruginous sand stone and mud stone. A field experiment was carried out to study the performance of different crops and grasses under variable soil depths. Crops namely, clusterbean (Maruguar), greengram (K 851), sesame (GT2), groundnut (GG2) and pearl millet (Pusa 23) and grasses C .ciliaris (CAZRI-75) and L. sindicus (CAZRI 30-5) were grown in these four different soil depths.

Abstract

The experiment, conducted at research farm of Central Arid Zone Research Station, Bikaner during 2009 on sandy loam soil. The study revealed that in agri-horti system different irrigation levels significantly affected the growth parameters (plant height, stem girth and tree canopy) of fruit trees which was highest at 80% ETc irrigation level in intercropping of moth bean and cluster bean and it was significantly higher over no intercropping. Intercropping of sonamukhi gave 24.8% lower plant height of citrus over no intercropping. Highest fruit yield of citrus was recorded (40% fruiting) with intercropping of moth bean at 80% ETc irrigation level which was 51% higher over intercropping of sonamukhi.

Abstract
 
Pop sorghum, apart from popping qualities has also shown the potential fodder yielding abilities. A field experiment was conducted at University of Agricultural Sciences, Dharwad, Karnataka during kharif 2001 under rainfed situation.

Abstract

A field experiment was conducted at Mechanized Commercial Farm, College of Agriculture, Junagadh Agricultural University, Junagadh (Gujarat) during the Kharif-Rabi seasons of 2006, 2007 and 2008 to study the effect of tillage practices on yield of rainfed castor (Ricinus communis). The experiment was laid out in Randomized Block Design with four replications. The six treatments comprised viz., T_1- Conventional tillage (Cultivator + blade harrowing), T_2-Ploughing followed by cultivator and blade harrowing, T_3-Tillage through rotavator, T_4-Furrow opening through sub-soiling, T_5-Furrow opening through V-notch cultivator and T_6-Zero tillage (pre and post emergence herbicides + 2 hand weeding). Among the different treatments, the different growth and yield attributing parameters viz., plant height, number of spikes per plant, length of main spike, number of capsules per spike and test weight, seed and stalk yields, higher gross and net returns were recorded when field was prepared by ploughing followed by cultivator and blade harrowing. It also improved soil moisture content which was closely followed by tillage through rotavator (T₃) and furrow opening through sub-soiling (T₄).

Abstract

India’s livestock sector is one of the largest in the world. It has 56.7% of world’s buffaloes, 12.5% cattle, 20.4% small ruminants, 2.4% camel, 1.4 % equine, 1.5% pigs and 3.1% poultry. Dairy Entrepreneurship can be one of the important subsidiary occupations for farmers in rural areas. Since agriculture happens to be mostly seasonal in nature, thereby providing employment opportunities for the people on seasonal basis, there is a possibility of finding employment for many persons throughout the year through dairy farming. The farm income can be enhanced through this subsidiary activity.

Abstract

The paper presents the innovation of solar tunnel dryer; it is a walk in type semi-cylindrical poly house framed structure with UV-stabilized polythene sheet, where products on large scale could be dried under controlled environment. Chilly drying in solar tunnel dryer to reduce the moisture content from 83.4 % (w.b.) to about 9 % (w.b.) and Aonla pulp from moisture content of 81 %(w.b.) to safe moisture content 9.5 %(w.b.) successfully dried. 20-30^ºC of higher temperature was obtained in solar tunnel dryer over the ambient temperature, depends on product. In comparison to open sun drying to obtain the same level of moisture contents resulting in a net saving in drying time of 40-50% for solar tunnel dryer over open sun drying.

Abstract

This paper portray the generation of spectral signature library for semi arid area crops using hyperspectral data and the scope of the application of the generated digital library for the classification of the satellite imagery of similar regions.

Hypersprctral data have narrow bands which help to provide additional information related to observed features. In case of this agriculture study crop related information are gathered using hyperspectral sensors The variation in the observations are due to physic-chemical characteristics such as biochemical composition, physical structure, water content and plant ecophysical status. Using the hand held spectroradiometer the reflectance is captured for the bajra, moong, moth crops from the Rajasthan, India’s semi arid region. The observations have been taken for different dates considering the phenology of the crops. Hyperion data from EO-1 satellite have been used to implement the classification operation based on the spectral signature library of bajra. It is observed that the image with the crops can be classified according to the phenology difference.

Abstract

Droughts are normal recurring climatic phenomena that vary in space, time, and intensity. The spatial and temporal variability and multiple impacts of droughts provide challenges for mapping and monitoring on regional scales. Large historical datasets are required in drought studies to understand the complex inter-relationship between the climatic and meteorological data. Extraction of valuable information from such large data archives demands an automated and efficient way. Data mining is answer to above problem as it has the potential to search for hidden pattern and identify the relationship between the datasets. For the current research, rainfall data from 1951-2006 was used to compute Standardized Precipitation Index (SPI) and NOAA-AVHRR NDVI images for the period 1981-2006 was used to calculate Vegetation Condition Index (VCI). SPI and VCI were used as input parameters in the Apriori Algorithm for generating the association rules. Interesting rules were developed identifying the relationship between user-specified target episodes and meteorological events. Therefore, spatial and temporal pattern of drought was achieved with 88% confidence.

Soil fertility -importance

From edaphological point of view soil is a medium for plant growth. It holds and nourishes the plants. Soil fertility refers to the ability of soil to supply plant nutrients. Soil fertility and fertilizers are very much closely related terms; and cannot be neglected one from the other in their function. Soil fertility acts as a ‘SINK’ where in plants can draw nutrients for maximum productivity, where as fertilizer, acts as a ‘SOURCE’ wherein we can apply continuously different nutrients. The importance of soil fertility and nutrient management is being increasingly recognized in all countries recently to meet the demand for food and other agricultural raw materials. Intensive use of fertilizer, intensive cropping and high yielding seeds have no doubt increased the food production and reduced the food shortage but it has also ushered in innumerable problems of soil fertility, soil and water pollution. On the other hand, fast depletion of nutrients due to over exploitation, a wide spread deficiency of N, P, K and S coupled with micronutrients deficiencies specially Zn, B and Mo is taking place. Further deforestation, shifting cultivation, burning of crop residues, trees, bushes, grasses and cow dung, soil erosion, nutrient losses and imbalanced nutrient application, leaching losses etc., have aggravated the depletion of soil fertility status. The productivity of Indian agriculture solely depends on scientific management of soil fertility along with judicious and efficient use of fertilizers integrated with organic sources.

Fertilizer

Fertilizers are defined as materials having definite chemical composition with a high analytical value that supply essential plant nutrients in available form. They are usually manufactured by industries and sold with a trade name. They are commonly synthetic in nature and also called as chemical fertilizers/inorganic fertilizers/commercial fertilizers other than lime and gypsum. Most of the chemical fertilizers are inorganic in nature.

Abstract

The Mesozoic sediments contribute around 54% of the oil and 44% of the gas reserves of the world (Bois et al. 1982). Indian Mesozoic basins occupy an area of about 400 x 103 sq. km and are characterized as frontier basins under category II - IV. These basins are mostly overlain by the Deccan Traps of Late Cretaceous age and are least explored. Deccan Syneclise is one of the largest Mesozoic basins in India, covering an area of ~ 273 x 103 sq. km. Geophysical studies have inferred hidden sub-trappean Mesozoic sediments with thickness up to 2.5 km. It is considered that requisite heat generation due to Deccan Trap volcanism soon after the Cretaceous sedimentation may have acted as a catalyst in hydrocarbon generation. Surface geochemical prospecting surveys along with carbon isotopic studies have been used to assess hydrocarbon generation potential of this part of the basin. The area adjoining Nandurbar beneath Narmada-Tapti region of Deccan Syneclise was selected for geochemical studies where geophysical studies have shown considerable sediment thickness. Surface geochemical studies indicate the generation of light gaseous hydrocarbons, C1 and SC2+ in the range of 3 to 1187 ppb and 1 to 1449 ppb, respectively. The carbon isotopic signatures of selected soil gas samples dC13 CH4 in the range of - 24 to -39.4‰ PDB) suggest thermogenic origin

Abstract

The groundwater behaviour in hard rock aquifer systems has always remained enigmatic owing to the heterogeneity of the aquifer systems. This is the reason why there are a lot of failures in groundwater targeting and management in hard rock aquifer systems even after the employment of many modern technologies. For precise groundwater targeting in hard rock aquifer systems various parameters like lithology, the type and the degree of structural deformation, the degree of weathering, geomorphology, etc., will have to be analysed which involves spatial analysis of voluminous data. In the sphere of spatial modelling, GIS plays an important role. Hence, a newer study has been carried out in parts of Madurai, Dindigul and Theni districts, Tamil Nadu, to identify the groundwater provinces and their functions using GIS. In the said study, GIS images were generated on the groundwater targets through GIS integration of transmissivity, permeability, storage co-efficient and water level. Such GIS image showing groundwater maxima was overlaid with GIS image of fracture maxima, subsurface geology maxima and the geomorphology maxima and thus by various GIS based spatial manipulations, aquifers controlled by structure, geomorphology, subsurface geology, and combinations of the above various variables were brought out. This has provided potential method for precise targeting of groundwater.

Abstract

It is evident from the previous studies that, in the crystalline terrain, the Fractures / lineaments act as master conduits for the groundwater movements and also act as favorable loci for groundwater storage. Because of this, the mapping of fracture patterns has become very popular among geoscientists. However, after witnessing failures and the fractures turned out to be water barren at many instances, geoscientists have started concentrating more on understanding the origin and the morphology of the fractures for precise groundwater targeting. In this context, a study has been conducted in parts of Western Ghats in Madurai, Dindigul and Theni districts of Tamil Nadu, South India, using remote sensing and geographic information system (GIS). In the said study, the maxima zones of transmissivity were studied in relation to fractures systems, which are normally reflected as lineaments in satellite images in the area. This study in general indicates that the transmissivity is controlled by the fractures, which are interestingly the active faults of the Quaternary period in the area.

Abstract

Three villages were selected randomly representing the flood affected areas of Dhemaji district of Assam. Analysed data on climatic parameters like rainfall(mm), temperature(oC), potential evapotranspiration (mm), relative humidity (%) of last 10 years collected authentic sources and depth of ground water table  was collected from the well water depth from the three villages for twelve months showed that the length of growing period was more than 300 days and during July to September the ground water table is above the soil surface i.e. there is flood in this period, but during January to March, it is very low and water becomes inadequate for growing crops. Other climatic parameters are most suitable for both Kharif and Rabi crops, but annual flooding affects the crop during July to September. From the study it was concluded that short duration varieties of different crops like that of paddy, pulses, oilseeds etc. may be grown at pre and post flood condition.

Abstract

Climate change and variability can adversely affect the poultry production in India, because birds can only tolerate narrow temperature ranges. Thermal stress on poultry is major concern. Heat and clod stress can cause immunosuppression and make birds more prone to infectious diseases. Climate change affects the occurrence, distribution and prevalence of poultry diseases.  Nutritional strategies aimed to alleviate the negative effects of heat stress by maintaining feed intake, electrolyte and water balance or supplementation of micronutrients such as vitamins and minerals to satisfy the special needs during heat stress have been proven advantageous. Ventilation and cooling methods are essential for birds to survive high summertime temperatures. Tunnel ventilation coupled with evaporative cooling is very effective in keeping birds cool during hot weather. The increasing proportion of poultry production in tropic and subtropical region makes it necessary to reconsider the selection strategy and potential use of naked neck and frizzle genes for improving heat tolerance in chicken.

Macroclimate : It deals with the study of atmosphere over large areas of the earth and with the large scale atmospheric motions that cause weather. It helps in forecasting weather. OR Climate of a continent or over the complete globe.
 
Macrometeorology : A branch of meteorology concerned with the study of large scale meteorological phenomena over a continent or the entire globe.

Macroscale : The meteorological scale covering an area ranging from the size of a continent to the entire globe.
 
Marine climate : Almost similar and on many occasions used as a synonym to maritime climate. The climate is basically influenced by adjacent seas and oceans.
 
Maritime Climate : The climate experienced in areas and regions near the oceans and seas. It is characterised by hot dry summers and mild wet winters. The diurnal variations of temperature are small and air is with high relative humidity.

Pan Coefficient (Kp) : It is the ratio between reference evapotranspiration (ET_o ) and water loss by evaporation from an open water surface of a pan (E_pan ).
    K_p = ET_o / E_pan

Peat soil : An organic soil containing more than 50 per cent organic matter.

Pan Evaporation : is the value of evaporation from an open pan evaporimeter (usually from standard USWB, class ‘A’ pan evaporimeter) during a day or specified period at a place.

Parcel : A volume of air small enough to contain uniform distribution of its meteorological properties and large enough to remain relatively self-contained and respond to all meteorological processes.

Walker Circulation : A thermally driven longitudinal cellular circulation over equatorial oceans, particularly Pacific Ocean, Peruvian coast, etc. These circulations rise in the West and sink in the East.
 
Warm Air : If the temperature of air is relatively warm as compared to an underlying surface or another adjacent air column or within itself, then the air is said to be warm air.

Warm Front : A front whose movement is such that the warmer air mass is replacing colder air mass.
 
Warm Sector : The state of lower troposphere in between a warm front and the following cold front. 

Wind influences the plant life both physiologically and mechanically. Wind affects plant directly by increasing the transpiration and intake of CO₂. Thus raising the supply of CO₂ to the plants and thereby increase in photosynthesis. However, the increase in photosynthesis is again upto a certain wind speed beyond which its rate become constant. The warm and dry winds increase evaporative loss and cause moisture stress. Lodging is one of severe injury caused by strong winds which causes great yield loss depending upon the stage of crop. This injury is common in paddy, maize, wheat, sorghum and sugarcane. Strong winds damage fruit trees extensively by breaking leaves and twigs and causing fruit drops.

The change of state of water form solid or liquid to gaseous form is known as evaporation. It may be defined as the water loss in vapour form from a soil/water surface. The energy used in this process is called as latent heat. The energy of 540 cal/g of water is used in this process. This process plays a major role in the redistribution of thermal energy between the earth and the atmosphere. Water vapour diffuses into the atmosphere from the different natural surfaces like ocean, river, lake, pond, soil and plant etc. It is difficult to measure the evaporation from the natural surfaces. To measure the evaporation from open water surface is easy and is normally in practice. The rate of evaporation is dependent on the size of the measuring surface (Pan) at constant wind speed below saturation point. Therefore a measured surface (Pan) is designed to measure the evaporation.

Dew acts as a source of moisture for the crop plants. It causes reduction in transpiration rate and saving of soil moisture reserves. Dew fall helps in insect-pest and diseases spread in crop plants.

14.1 Dew and Conditions for Dewfall

The radiational cooling during night causes the moisture to saturate and further cooling results into condensation and depositing this moisture in the form of tiny droplets on the grasses, vegetative and other non-conducting surfaces. This deposition form is known as dew. Clear nights, low wind velocity in the order of 1.0 to 3.0 m/s, presence of moderate to high moisture (RH = 75%) and sufficient radiational cooling are the four necessary and conductive conditions for the occurrence of dew.

Pressure of air at a given place is the force exerted against a surface by continuous collision of gas molecules. Pressure may be defined as the force per unit surface area.

Climate change and its variability imposed a great threat to agriculture production and ultimately on food security. Understanding of anomalies in climatic variables is essential to make agriculture sector resilient. Jharkhand state, geographically located at 220 28’ N – 250 30’ N latitude and 830 22’ – 870 40’ E longitude with an altitude up to 1142 m above msl and having humid to sub-humid tropical monsoon type of climate, has a number of agro-climatic/physiographic constraints. The state has 3 agroclimatic sub-zones viz; Central and North Eastern Plateau sub zone (zone IV), Western Plateau sub-zone (zone V) and South Eastern Plateau sub-zone (zone VI) falling under agroecological regions XI, XII and XIII. Zone IV is having 15 districts; Zone V has 6 and Zone VI have 3 districts. Agriculture in Jharkhand is very tedious due to topographical, physiographic and climatic constraints. Vagaries of climate put greatest limitation before the agricultural production system in the State.

Increasing evidences over the past few decades indicate that significant changes in climate are occurring across various regions of the globe in the form of increased occurrence of extreme weather events. The significant cause to this sustained increase in climate variability, known as climate change has been a resultant of increased level of greenhouse gases (GHGs) in the atmosphere. The reason for this increase is mainly ascribed to enhanced human activities such as industrialization, uncontrolled burning of fossil fuels, increased use of refrigerants and changed land use patterns and practices. Most significantly, the concentrations of GHGs like CO₂ has already crossed the 400 ppm mark, while other potential contributors like methane and nitrous oxide also show significant rise. As a result of the heat absorbing capacity of these gases, there has been a considerable rise in global mean temperatures, more so in the recent decade and more. The increase in mean air temperatures of the globe was 0.76^ºC during the past 100 years. This rate of increase has been higher during the past two decades and the recent period recorded the warmest years in sequence, the latest being the 2017.

Climate change has become real and tangible affecting people. It is a major challenge for agriculture, food security and rural livelihoods. Climate change impacts on vulnerable groups have social, economic, political, and environmental implications. The impacts of climate change are global. India is more vulnerable in view of the high population depending on agriculture, which in turn is dependent on the seasonal monsoons. India is confronted with the challenge of sustaining rapid economic growth amidst the increasing global threat of climate change. Government of India has accorded top priority for addressing climate change related concerns.

Introduction

Agriculture plays a crucial role in ensuring food security, accounting for a significant share of India’s Gross Domestic Product (GDP). Agriculture is not just about food production alone, since it is a complex multi-dimensional and multi-faceted sector which concerns the efficient use of the natural resources, productivity enhancement, and preservation of the ecosystems in a manner that can sustain the needs and improvements of human livelihoods (Devendra, 2012). It is also a most vulnerable sector to climate change which has been recognized as one of the most serious challenge for the world- its people, the environment and its economies. Increased incidence of abiotic stresses (drought, high & low temperature, salinity, submergence and oxidative stress) and biotic stresses (pest and diseases) have became major cause for stagnation of productivity in major crops (Grover et al., 2011). Abiotic stresses are directly correlated with the change in climate while biotic stresses are indirectly correlated as the pattern and incidence of disease varies with the variation in climatic condition. Also, crop productivity rely on extent and type of stress in the particular area.

Introduction

Sustainable agriculture is the production of food, fiber, or other plant or animal products using farming techniques (including agroforestry) that protect the environment, public health, human communities, and animal welfare. This form of agriculture enables us to produce healthy food without compromising future generations ability to do the same. Sustainable agriculture describes farming systems that are capable of maintaining their productivity and usefulness to society indefinitely. Such systems must be resource-conserving, socially supportive, commercially competitive and environmentally sound. It is a system of agriculture that will maintain its productivity over the long run. Sustainable farming could be organic farming, biodynamic, perma-culture, agro-ecological systems and low input. The goal of sustainable agriculture is to minimize adverse impacts to the immediate and off-farm environments while providing a sustained level of production and profit. Sustainable agriculture is influenced by environmental climate, soil types and the various crops and types of farm practices employed (Olorunfemi, 2013).

Introduction

In order to define climate it is important to distinguish it from weather. The weather that we experience on a day-to-day basis is a momentary atmospheric state characterized by temperature, precipitation, wind, and so on, and seems to vary in an irregular way, not following any particular pattern. Climate is a very general term that has a variety of closely related meanings. Usually, climate refers to the average weather conditions observed over a long period of time for a given area. In contrast to the instantaneous conditions described by weather, the timescale upon which climate statistics are calculated is typically thirty years. There can be variations in climate from year to year, or one decade to another, one century to another, or any longer time scale. The climate of a region depends on many factors including the amount of sunlight it receives, its height above sea level, the shape of the land, distance from the equator and how close it is to oceans. Generally speaking, the climate remains stable over long periods of time if the various elements within the system remain stable. However, if one or more of the components of the system is altered, the stability of the whole system is compromised and can lead to uncharacteristic behaviour and give rise to weather, which is outside the usual range of expectations. This situation can be described as climate change.

Heat stress induced by climate change is a serious issue of livestock industries worldwide (Bajagai, 2011). When environmental temperatures move out of the thermo-neutral zone (or comfort zone) animals begins to experience either heat stress or cold stress. Both these stresses require the animals to increase the amount of energy used to maintain the body temperature so that less energy is available for productive processes. Atmospheric temperature, relative humidity, air movement and solar radiation are the major factors that determine the heat load on animal. Thermoregulation is the ability of the animals to maintain their body temperature in cold or hot environments. It consists of behavioural, physiological and anatomical responses that affect energy metabolism. At lower temperature as a physiological adjustment to maintain the body temperature the animal increases the metabolic heat production by increasing the basal metabolic rate and uncoupling of oxidative phosphorylation. Hence the maintenance energy requirement of animals increases in a cold environment, which reduces the amount of energy available for production. From a practical point of view higher temperatures are much more dangerous for producing animals than a cold environment. Temperatures exceeding the higher critical level compromise animal performance not only by changing the energy and nutrient metabolism, but also by upsetting the body homeostasis, with detrimental consequences both for immune competence and for product quality. In general, livestock with high production potential are at greatest risk of heat stress, and require most attention.

Climate change is one of the most serious and long standing challenges facing livestock around the world and has moved up to the top of agenda among scientific community, civil society, business and government. Majority of scientific experts around the world believe that the climate change is already occurring by human activities, by use of fossil fuel, deforestation and agricultural practices, livestock rearing and that the developing countries in particular would be more vulnerable to the continuously changing climate. Rise in temperature due to climate change is likely to affect livestock production and health. Large deltas and low lying coastal areas would be inundated by a rise in sea level along with increased precipitation intensity. (DFID, 2004).Major contributors to the climate change are the man-made greenhouse gases, such as carbon dioxide, methane and nitrous oxide and hydroflurocarbons in the atmosphere. The accumulation of gas is causing the climatic change globally, as evident from the increased frequency of floods, droughts, cyclones and torrential rains in the recent past. The green house gases (GHGs) emission from agriculture sector alone accounts for 25.5% of global emission and over 60% from anthropogenic sources (FAO,2009)

One Health is defined as “the collaborative effort of multiple disciplines working locally, nationally, and globally to attain optimal health for people, animals and the environment.” The concept of ‘One Health’ dates back to the Greek physician Hippocrates (ca. 460 BCE–a.370) who in his text “On Airs, Waters and Places” stated:

Whoever wishes to investigate medicine properly, should proceed thus: in the first place to consider the seasons of the year, and what effects each of them produces, for they are not all alike, but differ much from themselves in regard to their changes.