eChapters

There is a range of thermal conditions within which animals are able to maintain a relatively stable body temperature by means of behavioral and physiological means. Heat stress results from the animal?s inability to dissipate sufficient heat to maintain homeothermy. High ambient temperature, relative humidity and radiant energy compromise the ability of animals to dissipate heat. As a result, there is an increase in body temperature, which in turn initiates compensatory and adaptive mechanisms to re-establish homeothermy and homeostasis. These readjustments, generally referred to as adaptations, may be favorable or unfavorable to economic interests of humans, but are essential for survival of the animal. Thus, an increase in air temperature, such as that expected in different scenarios of climate change, would affect directly animal performance by affecting animal heat balance. Potential direct and indirect impacts of climate change on livestock production have not been thoroughly explored. Changes in crop availability and quality, which have been the primary focus of previous studies, affect animal production through changes in feed supplies. Analyses of direct impacts of climate change on livestock production are few. Changes in climate would directly lead to reductions in summer season milk production and conception rates in dairy cows. Because voluntary feed intake (VFI) is the primary factor influencing the production capacity of livestock, accurate prediction of the feed consumption of livestock under heat stress is a precursor to accurate assessment of changes in production resulting from changes to a warmer climate. Quantification of potential impacts of climate change on livestock production allows producers to gain a better understanding of the magnitude of the changes in production levels faced under climate change. Projected economic losses resulting from temperature-induced reductions in production may justify mitigation of these temperature increases through changes in management practices, such as installation of shades or sprinklers in feedlots or evaporative cooling of barns. With severe economic losses predicted in livestock as a result of climate change, it?s very essential to understand the different intricacies of climate and its impact on livestock production. This will help us to prepare ourselves better for ameliorating the adverse impact of weather parameters on animal production. This will intern prevent the severe economic losses incurred in livestock industry as a result of changing climate.

Domestication of animals was followed by the provision of shelters for protection which also modified the climate to suit the species housed for improving the productivity and reproductive efficiency. Climate is the long term average condition of the meteorological variables in a given region. The climate is divided into macro climate and micro climate. Macro climate is the general large scale climatic conditions of the open atmosphere in a large area. Micro-climate is the climatic conditions directly surrounding the animal or the physical environment in the immediate vicinity of the animal. The environment includes all the combination of conditions under which the animal lives. The immediate variables that affect the production and reproduction of animals are its micro climatic variables. The animals have requirements of their own. The environment influences where and how animal lives. Domestication has resulted in man dictating where and how animal lives. Thus breeds of livestock evolved in temperate regions have been introduced into tropical area with high rainfall, humidity and temperatures. Homeotherms are a group of animals which maintain their deep body temperature essentially constant. All the domestic animals are homeotherms. In the case of an inert body, basic thermodynamic forces establishes an equilibrium in which the body attains the same temperature of the surrounding environment. The same law applies to homeothermic animals also. Therefore, these animals will have to make compensatory physiological and behavioural adjustments to keep a constant deep-body temperature. While digestion of food takes place in the body of animals, a portion of the energy in the feed is converted into heat. This metabolic heat plus the heat gained from the environment through conduction, convection and radiation results in excess heat gain to the animal, which has to be dissipated, if heat balance is to be maintained. For this the animal depends on various physiological and behavioural functions. This balancing act by which a constant normal core temperature is maintained is known as homeothermy. Heat production is regulated by hormonal secretions, changes in muscle tone, shivering and by voluntary muscular activity. Heat loss is controlled by vasodialatation, increasing the cutaneous circulation and evaporative loss. The animal reduces its feed intake as well as production, drink more water. In long term the hair coat becomes lighter with less insulation. The animal will also exhibit postural changes and behavioural adjustments. They will try to increase surface area, reduce physical activity and seek shade.

The influence of the vagaries of weather on all species on the earth is ubiquitious. It exerts its profound influence on the health, moods and activities of the humans, on all the Agriculture operations right from the seeding stage to the harvesting stage and on the health, behaviour and production of the animal life. Crop growth, is influenced by the variation of the meteorological parameters such as temperature, rainfall and wind etc. It is estimated that in some countries the losses due to adverse weather conditions amount to as much as 30% of the annual agricultural production. This type of losses, many times prove disastrous in the countries whose economy is mainly agriculture based, like that of ours. While the favourable weather conditions increase crop yield, the adverse weather, damages the crop giving rise to very low yield. The weather elements play an important role in governing the crop performance. Similarly weather elements also found to be controlling the Livestock production. It hence becomes necessary for the agriculturists and the veterinarians to have some basic knowledge of Meteorology to get better equipped for problem solving in their respective fields. All the weather phenomenon whether beneficial or disastrous are enacted in the natural theatre which is called the atmosphere. Hence to start with one has to study the characteristics of the atmosphere before proceeding further in meteorology.

The atmosphere is a thin layer of gases surrounding the Earth?s surface, which is retained by the earth?s gravity. The atmosphere protects life on the earth by absorbing ultra violet solar radiation and reduces the temperature extremes between the day and night. The atmosphere has no abrupt cut-off. It slowly becomes thinner and fades away into space. There is no finite boundary between the atmosphere and space. Three quarters of the atmosphere by mass is within 11 km of the planetary surface. In fact half of the atmosphere is contained within 6km from the surface. The Karman line, at 100 km is frequently used as the boundary between the atmosphere and space. The atmosphere contains by volume roughly 78% nitrogen and 21% of oxygen, trace amount of other gases and water vapour. This mixture of gases is known as air. The atmosphere also contains water vapour in smaller quantities. The amount of all these gases except water vapour is more or less constant while the water vapour is highly variable and yet its presence is essential for the development of any weather phenomenon. Based on the thermal characteristics, chemical composition, movement and density, the atmosphere is divided into four distinct layers. They are troposphere, stratosphere, mesosphere & thermosphere. The first 64–80 km above the earth contains 99% of the total mass of the earth?s atmosphere and is generally of a uniform composition, except for a high concentration of ozone, known as the ozone layer, at 12–30 mi (19–50 km). Because of the pull of gravity the density of the atmosphere and the pressure exerted by air molecules are greatest near the earth?s surface. Air pressure decreases quickly with altitude, reaching one half of its value at about 5.5Km. The density of air at sea level is about 1.2 kg/m³. The atmospheric density decreases as altitude increases.

It is necessary to consider both micro and macro climate while planning scientific livestock management strategies. Thermal comfort of animals is the most important environmental consideration affecting the production performance of domestic animals in general and the dairy cattle in particular. Various components of climate like air temperature, humidity, solar radiation, wind velocity and precipitation affect the thermal comfort of animals and their performance. As these factors produce a combined effect rather than each component alone thermal indices involving two more of these factors are useful for rational decision making information for livestock managers. Considering only the direct effects of microclimate will be an over simplification of the problems because the indirect effects of the macroclimate operating through feed supplies, feed quality, parasitism, and other factors are equally or more important. These factors confound the direct effects of climatic elements and under many situations far overshadow their effects. Thus, evaluation of the direct and indirect effects of climate independent of each other is necessary. We will also examine each factor separately for easiness of understanding keeping in mind that the heat exchange of the animals with their environment is a combined effect of all these intertwined with complex biological and physical factors. Yamamoto (1983) concluded “Heat exchanges between animal and their environment are not readily explainable in terms of physical principles because the relationships are considerably modified by animal factors”. The combined effects of the climatic factors involved in heat exchange between any homoeothermic animal and its surrounding has led to the development of Thermal Indices as a basis for assessing the biological effect and consequent impact of thermal environment (Hahn 2003). Studies on the thermal environment and methods to represent in reliable indices are more important in the tropical world in general and hot tropical humid world in particular.

The advantages and disadvantages of thermal indices and how it can be used as useful guide for environment management of dairy cows are illustrated in this paper through examples. Many salient basic aspects were noted by Thomas C.K. way back in 1969 but the exact use of this information for the farmers is a far cry.

One of biggest challenges facing animal science is to increase the production in the context of climate change. Animal performance may be limited by adverse climatic focus (Sejian et al., 2010; Sejian et al., 2012). The economic impact of climate changes in relation to livestock production are widely reported, and several losses are predicted if current management systems are not modified to reflect the shift in climate. Climate change poses formidable challenge to the development of livestock sector in India (Sejian et al., 2013; Naqvi et al., 2013). Global warming could increase water, shelter and energy requirement of livestock for meeting projected milk demands. The anticipated rise in temperature between 2.3 and 4.8°C over the entire country together with increased precipitation resulting from climate change is likely to aggravate the heat stress in dairy animals, adversely affecting their productive and reproductive performance, and hence reducing the total area where high yielding dairy cattle can be economically reared. A preliminary estimate indicates that global warming is likely to lead to a loss of 1.6 million tonnes in milk production in India by 2020.

Seasonal variations in climatic conditions impact the availability of feed in the livestock (Sejian et al., 2014; Bagath et al., 2016). Over and above the effect of seasonal variations that cause considerable economic hardship, it is the unforeseen and unexpected periods of inclement and severe weather conditions which exacerbate the gross economic losses in livestock industry (Sejian and Srivastava, 2010; Sejian et al., 2010). In addition to mortalities of livestock associated with severe climatic conditions, reductions in reproductive and productive performances generate sizeable economic setback. Impressive advances in research have been made to assess the impact of climatic stressors on the physiological and dynamic responses of livestock (Shaji et al., 2015; Maurya et al., 2015). At the same time livestock managers and farmers continue to search for management options which can alleviate and reduce the effects of severe weather on livestock performance and productivity. This chapter will address in detail the impact of environmental stresses on livestock production and reproduction. These attempts will help the scientific fraternity to develop appropriate mitigation strategies to improve ruminant livestock production in these agro-ecological zones. This might pave way to improve the livelihood securities of poor and marginal farmers of this tropical environment via an appropriate universal research agenda.

All animals have a range of ambient environmental temperatures termed as thermo-neutral zone. This is the range of temperatures that are conducive to health, performance and well-being. The upper critical temperature is the point at which heat stress begins to affect the animal adversely. There are a number of climatic factors like temperature, humidity, wind speed and radiant energy/sunlight that influence the degree of heat stress. Heat is also produced by metabolism within the body, which includes maintenance, growth and production. Heat production is affected by body weight, species and breed, level of production, level of feed intake, feed quality and, to a lesser extent, by the amount of activity and exercise. Excluding temperature of the air ventilating the house, heat is also added from the roof and walls. Heat stress can be defined as the point where the animal cannot dissipate adequate quantity of heat to maintain body thermal balance. During the periods of heat stress, most of the productive energy is diverted to thermoregulatory adaptations that results into decreased weight gain, poor immunity, oxidative stress predisposing animals to various infectious diseases and high mortality rates. In order to characterize and quantify thermal comfort zones according to animal species, several thermal comfort indices or heat stress indices were developed.

The primary focus for livestock and poultry has been on heat stress indices to provide guidelines for environmental management and risk assessment for losses through linkages with physiological responses (Eigenberg et al., 2005) or performance (Baccari, 2001). The linkage is based on observations of a selected performance criterion (e.g., growth, milk or egg production) made concurrently with measures of the warm environment. These serve as inputs for the selected heat stress index and thus an empirical relationship can be developed which is termed as ?biological response function?. These indices recognize the ability of the animal to cope with environmental stressors by adjusting physiologically, behaviourally and immunologically to minimize adverse effects or even compensate for reduced growth and production performance during moderate environmental challenges. When the intensity and duration of potential stressors exceed thresholds, coupled with limited opportunity for recovery, animals are unable to cope and therefore are affected adversely. Nevertheless, the heat stress indices have served as useful surrogates for the complex interactions between the physical and biological components (Hahn et al., 2003).

The most of the animal population of the world?s lies in regions where frequent seasonal stressors adversely influence the health and productivity. The adaptation of animals to thermal stress is a physiological; biochemical process under endocrine control opens new opportunities to use of endocrine regulation as means of improving thermal tolerance. The animals raised in the semi-arid tropics, usually exhibit low productivity because of shortages of feed and harsh climatic conditions (Maurya et al., 2004). Heat stress can impact animal production and profitability in dairy cattle by lowering feed intake, milk production and reproduction. The animal production is affected by elevated ambient temperature which intern affects the availability of quality feed fodder and water. The indirect effects of climate driven changes in animal performance result mainly from alterations in the nutritional environment of the grazing livestock (Topp and Doyle , 1996). In tropical region most of the time is being spent by animals in the search of feed and fodder. The excess walking stress in the livestock reduces their body condition score and oftenly animal exposed to negative energy balance (Maurya et al., 2010). Under present climate conditions, the lack of ability of animals to dissipate the environmental heat determines that, in many areas in the world, animals suffer heat stress during, at least, part of the year. Heat stress has a variety of detrimental effects on livestock (Fuquay, 1981), with significant effects on milk production and reproduction in dairy cows (Johnson, 1987). The severity of stress and milk production by a cow depends on THI, length of heat stress period, air flow, size of cow, dry matter intake, water availability and coat colour.

At the moment India is world leader in milk production, closely followed by the USA, with a production volume of 84 million tons. More than half of the milk is produced by buffaloes. India has about three times as many ?dairy? animals as the USA, the vast majority (over 80 percent) being kept in herds of 2 to 8 animals. Annual milk yield per dairy animal is about one tenth of that achieved in the USA and about one fifth of the yield of a New Zealand dairy cow. As per India?s National Dairy Development Board (NDDB), the country produced 121 mt of milk in 2010-11 fiscal, which comprised about 17% of global production.

Livestock are homeotherms and has to maintain their body temperature at a fairly constant level through various means of heat gain and heat loss mechanisms. In order to survive in an environment for longer period the energy gain must equal to energy loss. The remarkable interaction has occurred between climate, soil, plants and animals during course of evolution. The maintenance of high level of production in hot regions is difficult as the large amount of heat has to be dissipated besides heat imposed by the environment. Similarly in cold regions, the animal has to produce extra heat to meet the thermoregulatory demand. Considerable variations occur between different species, and between different individual within a species in their capacity to adjust to environmental stress. The farm animals prefer an internal body temperature range from 36-40°C. Normal body temperature of livestock species are:

Cattle: 101-102^oF, Buffalo: 100.5-102°F, Sheep: 102-103°F and Goat: 102.5-103^oF

All the metabolic reactions are under control of various enzymes. The optimum ranges of temperature for activities of these enzymes incidentally fall in the range of normal body temperature. The body keeps its core temperature constant at about 37°C by physiological adjustments controlled by the hypothalamus. A group of neurons, located in anterior hypothalamus, are sensitive to change in skin as well as blood temperature. This hypothalamic centre acts as a “thermostat”. When core body temperature deviated from the thermostat temperature, numerous thermoregulatory mechanisms are initiated to bring back the core body temperature normal. However, in certain instance eg. fever the set point temperature of thermoregulatory control centre is raised. The hypothalamic thermostat works in conjunction with other hypothalamic, autonomic and higher nervous thermoregulatory centers to keep the core temperature constant. Some of these thermoregulatory responses are involuntary, mediated by the autonomic nervous system, some are neurohormonal and others are semi-voluntary or voluntary behavioral responses.

Selye, H (1936), the pioneer in stress physiology, defined stressors as noxious stimuli that increase adrenocorticotropic hormone and clubbed these stimuli under the term stress. Rivier and Rivest (1991) and Chrousos and Gold (1992) defined stress as “a state of disharmony, or threatened homeostasis.” Stress challenges homeostasis, but does not disrupt it, in an adapting organism. McEwen (2000) defined stress as a “real or interpreted threat to physiological or psychological integrity that results in physiological and/or behavioral responses.” The following are the various stressors:

Scientists rely on a variety of endocrine, behavioral, autonomic nervous system and immunological end points to measure stress. Unfortunately, none of these measures has proved to be a litmus test for stress. Increased secretion of the adrenal glucocorticoids and cortisol has been found to be associated with stress and investigators frequently cite an increase in circulating cortisol as a proof of stress. Colborn et al., (1991) found that stallions secreted similar amounts of cortisol whether the stallions were restrained, exercised or permitted to mate with a mare. Serum cortisol concentrations are often used to evaluate stress, but due to the marked variability, faecal corticosterone has been used to evaluate stress in cattle (Morrow et al., 2002). Dairy cattle secrets cortisol during restrained and when approached by strangers. So it is difficult to simply use secretion of cortisol or any other hormone to differentiate between non threatening stress and distress. Further, complicating is inter animal variability in stress response. Even among the same breed some cows may produce more cortisol to the same amounts of thermal stressors.

The UNFCCC (United Nation Framework Convention on Climate Change) has defined climate change as “a change in climate which is attributed directly or indirectly to human activity that alters the composition of global atmosphere which is in addition to natural climate variability” (UNFCCC, 2008). Ruminant animals, such as cattle, sheep, buffalo, and goats, are unique due to their special digestive systems which can convert otherwise unusable plant materials into nutritious food and fiber. This same helpful digestive system, however, produces methane (CH₄), a potent green house gas (GHG) that can contribute to global climate change. Livestock production systems can also emit other greenhouse gases such as nitrous oxide (N₂O) and carbon dioxide (CO₂). The most important GHG?s are CO₂, CH₄ and N₂O, which have increased in the last 150 years and have different global warming potential. According to Sejian et al., (2011) and Solomon et al., (2007), the warming potential of CO₂, CH₄ and N₂O are 1, 25, and 310, respectively. Taking into account the entire livestock commodity chain – from land use and feed production, to livestock farming and waste management, to product processing and transportation –Livestock?s Long Shadow attributes about 18 percent of total anthropogenic GHG emissions to the livestock sector (FAO, 2006). The Intergovernmental Panel on Climate Change (IPCC), convened by the United Nations, has reported evidence that human activities over the past 50 years have influenced Global Climate through the production of GHG, which results in increased absorption in the atmosphere of infrared radiations emitted from the earth?s surface. The accumulation of GHG results in increased global temperature which in turn can increase annual precipitation in high rainfall regions and decrease precipitation in regions of low rainfall (Gerstengarbe and Werner, 2008). This will affect water supplies, distribution of deserts and wet areas, the range and number of pests that affect plants or diseases and biodiversity.

Air, water and land constitute our environment and these are technically known as atmosphere, hydrosphere and lithosphere respectively. All these spheres together constitute the biosphere. In the biosphere, apart from human beings, plants, animals, birds, fishes, insects and microorganisms also exist. All these living beings get affected whenever a change, physical or chemical occurs in the biosphere. This change is termed as pollution and the agents that institute these changes are called pollutants. A kind of pollution that has come in to prominence more recently is radiation, causing environmental and health problems of immense magnitude. The radiation may either be natural like cosmic radiation from outer space and sun?s radiations or produced by disintegration of naturally occurring and manmade elements. Such radiation is not visible to our eyes, but can penetrate the body and do immense harm. Man and animals have been continually exposed to different sources of radiation. But the radiation levels were well within the tolerable limits in the past. Yet, since the mid 1970?s human activities have been changing the chemistry of atmosphere in a way that reduces the amount of ozone in the stratosphere which is responsible for protecting the living things from excessive amounts of ultraviolet radiation. Further, it is only after the advent of nuclear power stations that radiations increased to reach harmful levels. Though mankind has benefitted by harnessing nuclear energy for peaceful purposes, one cannot deny the inherent dangers of radiation. Nuclear power plants no doubt help in the production of controlled electricity. However, a worldwide controversy is ragging over the existing nuclear power plants and setting up of new plants particularly since 1986 disaster of Chernobyl nuclear plant in Russia. A fire in the plant allowed massive amounts of radiation to be released into the atmosphere. This fall out drifted into the Scandinavia and Eastern Europe causing enormous damage to crop and livestock.

Foot and mouth disease (FMD) is the most contagious disease of animals and has a great potential for causing severe economic losses in susceptible cloven-hoofed animals. FMD has been classified as a Transboundary Animal Disease (TAD) which is highly contagious or transmissible and has the potential for very rapid spread, irrespective of national borders, and causing serious socio-economic consequences. FMD has constituted a recognised threat to the health of livestock for over 500 years and still remains a serious hazard to the productivity of animal populations throughout the world. The large numbers of virus serotypes and subtypes, the ease of transmission and the limited efficacy of vaccination make control complicated and difficult. Contribution of environmental variables for emergence and distribution of infectious diseases has long been recognized by many researchers. India is largely subject to four seasons: winter (January and February), summer (March to May), a monsoon (rainy) season (June to September), and a post-monsoon period (October to December). There are reports on effect of environmental parameters such as relative humidity, windspeed and air temperature on the spread of the disease. FMD is endemic and at a high prevalence in many countries in Africa, the Middle East and Asia and is also present in parts of South America. Europe, North and Central America, the Pacific nations and the Caribbean are free from the disease. FMD in India is the biggest impediment to growth of livestock sector. FMD outbreaks occur in India throughout the year. The outbreaks occurred round the year with maximum occurrence during October to March, and in May and June (Fig. 15.1). Foot and mouth disease is associated with an aphthovirus (family picornaviridae) which occurs as seven major serotypes: A,O,C,SAT1, SAT2, SAT3 and Asia1. FMD is characterized by fever, profuse salivation, vesicles in the mouth and on the feet and a drastic reduction in milk production; sudden death in young stock may occur (Radostits et al., 2006).

The establishment and the longevity of the organisms from one to complex multiple cells are controlled both by climate and weather in a region. Climate(macro level physical factor) of a region permits a particular organism to initiate its establishment, while the prevailing weather (micro level of the climate factor) which is known to occur within that climate controls the growth and multiplication of the selected organisms and thus proving the immense need of both climate and weather to living organisms. Within this science, when the weather is favorable for a particular organism throughout the year in a region, which cause disease to higher organisms then that region is termed as endemic region to a particular disease, where the management is focused towards strategical(long term) and tactical(short term) approaches. When in a year, from few weeks to few months the weather may be highly favorable for the outbreak of a particular disease, then that region is named as epidemic region for that disease and by establishing scientific link between weather and disease causing organism, it is possible to forecast / predict disease initiation in time and practice tactical management. Among the weather factors, temperature(both maximum and minimum), rainfall (amount and its distribution), relative humidity(both maximum and minimum) wind speed, dew, fog and mist would influence the organisms causing disease in livestock both in positive and negative terms. This is the new emerging area in the field of animal climatology and an attempt has been made to integrate animal diseases with climate and weather factors based on the available literature. Scope for research is vast in this new area and is discussed in a sub-head of the conclusion.

The sole science of meteorology is to deal with weather forecasting while livestock advisory based on weather forewarning is dealt with multidisciplinary approach in the field of livestock meteorology for the benefit of the livestock farmers. In this context, the current status of livestock advisory based on medium range weather forecasting is highlighted so that the tools for livestock advisory can be initiated and developed by the concerned for the benefit of livestock farmers in similar lines. Information on weather forecasting is used in various society linked sectors and animal husbandry component is one of them (Fig. 17.1).

From very early times, humans were astonished, fascinated and frightened by the weather events and the dynamism of changes that weather brought around them. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century. He has tried to predict or forecast the weather mainly based on many indicators around. In the earliest record of weather forecast, the Babylonians have predicted the weather from cloud patterns as well as astrology in 650 BC. In 904 AD, Ibn Wahshiyya, an Iraqi alchemist and agriculturist in his work Nabatean Agriculture have discussed the behavior of plants and animals also along with atmospheric, planetary, solar and lunar signs in weather forecasting. This is perhaps the first work that have discussed about the animal and bird indicators for weather forecast. Though there are a variety of end uses to modern weather forecasts, indigenous knowledge and application of weather forecasts were mainly for agricultural operations. Farmers have to rely on weather forecasts to decide on what work has to be done on any particular day. They are astute weather watchers and are quick to recognize weather that is either favourable or unfavourable to their production systems. In traditional weather forecasting, the farmers has identified a set of indicators and developed a reliability factor for each of them. Predicting weather is also an important cultural component for farmers, as it is common for farmers to discuss weather indicators on the street, markets and with family members.

Farmers have used traditional knowledge to understand weather and climate patterns in order to make decisions about crop and irrigation cycles. This knowledge has been gained through many decades of experience, and has been passed on from previous generations, and the knowledge is also adapted to local conditions and needs. But the scientific forecasts are formulated at a much larger scale and so access to get location specific rainfall forecast to take proper decision at the farm level is very limited. Besides forecasting weather, the farmers has also evolved several coping strategies in rain-fed systems across the world and so today many international development agencies, universities and research institutions have started focusing on indigenous knowledge and have incorporated it in development perspectives.

Weather is the integrated effect of the atmospheric conditions at any given instant. Climate is the collective state of the atmosphere at any given place or over an area within a specified period of time (usually over 30 years? period).The branch of meteorology that deals with the science of climate is known as Climatology. Primarly the elements of climate are sunshine (solar energy), temperature, moisture and winds. Climate elements vary regionally and temporally. The most fundamental control of weather and climate is the unequal heating and cooling of the atmosphere in different parts of the earth. The zone of maximum solar radiation shifts northward and southward during the year, thereby producing seasons. When it is summer in the Northern Hemisphere it is winter in the Southern Hemisphere and vice-versa. Broadly speaking, both the hemispheres have two distinct seasonal climates in a year namely, the summer or comparatively hot climate and the winter or the cold climate. The atmospheric circulation patterns over the two hemispheres also undergo changes during these two distinct seasons. The change is phenomenal in the tropical regions. In the summer monsoon region, there is reversal of wind flow in the lower troposhere, sudden increase of precipitation etc. Besides the change in the general circulation pattern with the season, the climate of a place is affected by variety of local features such as vegetation, nature of the surface, the slope of the land etc. On the basis of climate, the period of a year has been divided into four seasons in India. They are:

Cold weather season (Winter season) – December and January; Pre-monsoon or Hot weather season – March to May; Southwest or Summer Monsoon season – June to September and Post-monsoon season - October to December. Each of these seasons has its own characteristic features of pressure and temperature distributions, winds, precipitation, humidity etc. The major synoptic disturbances in the Indian region also differ with the season.

According to “Artha-sastra”, first book on Governance, Agriculture, cattle breeding and trade, world?s first meteorological Instrument, a “Rain Gauge”, apparently a circular vessel with 20 fingers equivalent width and 8 fingers equivalent depth were installed by Kautilya (Chanakya) during 350-281BC throughout the Mauryan empire (Rainfall measurement:: 1 adhaka = 12mm, I drona = 40 to 50 mm). He is the first person to identify country?s economy depends on Rainfall. Good yield of rain-fed crop requires rainfall of 16 dronas was essential and 4 dronas rainfall is sufficient, also identified rainy season July to December wherein 2/3 annual rainfall receives during Mid-August to October end, now as per IMD norms Southwest monsoon season. He also identified his empire consists of FOUR CLIMATIC zones Tundra/Tropical Rain forest/Semiarid and Arid zones. With the modern seafarers, Columbus (1451-1506) Americus Vespucius (1454-1512) Italian Explorers, James Cook (1728-1779), British Explorer, Ferdinand Magellan (1480-1529), Vasco-de-gama (14601524) Portuguese Explorer and other Navigators of 15th to 18th Century faced severe cyclonic storm and rough weather over high sea felt the need of Meteorological and Navigational equipments. Inventions of modern day instruments started. For Navigators, Quadrant, Mariners Campus (dry), Sand glasses for time measurement (800-900AD) and accurate mechanical Watch (1759) were invented. From the term “NAVAGATHI”, modern term of “NAVIGATION” born. With the introduction of Hot air balloon flight in 18th Century, Air flights (after 1903) our knowledge of weather of upper levels of the atmosphere – knowledge of heights of standard pressure altitudes, Upper Air Temperature, Humidity, Wind direction and speed upto Troposphere. Radio-sonde ascents were commenced in 1936. Radars and Satellite images further increased knowledge about weather and assisting for the preparation of weather inferences useful for Seafarers, flight operators and General Public, Agriculturists, Live-stock managements, national level planners, trade and economists.

21.1 Automatic Weather Station

Automatic Weather Station, popularly known as AWS, is an electronic device and an automated version of the traditional weather station. Numerous weather sensors are connected to the system which automatically records and stores weather data. It is quite useful in remote areas where no frequent access is possible. The system requires hardware as well as software to log in, store, display, retrieve and analyze the data. The digital data recorded from AWS can be downloaded to the laptop through the memory device. The same digital data can be converted to the actual values indicating various weather parameters through the software provided along with the AWS. It should be also maintained in the desktop of PC/AT so that the data are doubly assured. Every AWS has its own software depending upon the manufactures. Time interval can be fixed for recording weather data depending upon the purpose since it is a continuous recorder. Continuous AWS data are integrated at hourly or half-hourly interval for monitoring weather data, otherwise enormous data are continuously stored and no way are used. Of course, continuous weather display is possible for monitoring weather conditions spatially and temporarily.

Automatic Weather Station consists of a datalogger, rechargeable battery, telemetry (optional) and the meteorological sensors with an attached solar panel. The system may report in near real time via GPRS or save the data for later recovery. Majority of automatic weather stations possesses normally Thermometer Sensor for measuring temperature; Anemometer for measuring wind speed; Wind vane for measuring wind direction; Hygrometer for measuring relative humidity; Barometer for measuring atmospheric pressure; Rain gauge for measuring rainfall and Pyranometer for measuring solar radiation. Automatic weather stations are based around a programmable datalogger that measures the sensors, then processes, stores, and transmits the data. Dataloggers have wide operating temperature ranges, on-board instructions, programmable execution intervals and input channels for commonly used sensors. Wind vector, wet bulb, histogram and sample on maxima or minima are standard in the datalogger instruction sets. Most sensors can be measured directly without external signal conditioning. Data are typically viewed and stored in the units of your choice(e.g., wind speed in mph, m/s, knots). Measurement rates and data recording intervals are independently programmable, allowing calculation of 15 minute, hourly, and daily data values from 1 minute or 1 second measurements, for example. Conditional outputs, such as rainfall intensity and wind gusts, can also be recorded. The program can be modified at any time to accommodate different sensor configurations or new data processing requirements.

The Agromet/Livestock advisories are issued on the basis of weather forecasts made at the meteorological centers. These forecasts are made by numerical methods which employ the process of solving the equations governing the motion of the air. For solving the equations, observations of various meteorological parameters such as pressure, temperature, wind direction and speed and other weather variables are required. The observations are taken at specified times called synoptic hours in all the observatories located throughout the World. The instruments used to measure the weather parameters are housed in the observatory. Instruments used for the measurement of different elements are given below:

In old days, Statistics is considered as a method for collected numerical information. In general, Statistics deals with concepts, principles and methods dealing with collection, summarization, analysis and interpretation of data. Data means a collection of numerical facts. Data is plural and singular is datum. Generally there are two classifications for data, quantitative and qualitative. In the case of quantitative character the individuals are measured. While in the case of qualitative character, the individuals are distinguished by some quality. Data collected by the investigator for the purpose of the investigation are known as primary data. E.g., data obtained in a population census. Data collected by others for some other purpose and is used by the investigator are known as secondary data. E.g., Annual Reports, Official publication etc. The aggregate of all the observations pertaining to a character is called a population. Sample is a part of the population selected according to some definite rule. Usually the sample is used to make an inference about the population. In other words sample is a miniature of the population. The methods by which we analyze the data are called statistical methods. At the end of the enquiry, the investigators will naturally left with a large number of filled up schedules and a very efficient statistician couldn?t interpret anything from it unless it is classified and extracted. When we classify based on the quality like colour, sex, religion etc. which can?t measure directly, the classification is qualitative. But characteristics such as height, weight, length, time etc. can be easily measured using a scale. Such are called quantitative characteristics. The quantitative characteristics may be discrete or continuous. In the case of numerical values like number of petals in a flower, number of days in which rain occurred in a month etc. are whole numbers and are called discrete variables. If there may occur many values with in an interval, we call it as continuous variables.

In the existing planetary system, life was established and growing over millions of years on earth. If we track down to the history of evolution, beginning with a living unicellular organisms Amoeba, growing to a gigantic size of Dinosaur and stabilizing at well adaptable stage of an Elephant in animal kingdom or to reach the present status of the intelligent human being, throughout these developmental stages the climatic/meteorological factors play a crucial and supportive role. Further the Development of plant/Animal kingdom is making rapid strides in tropical climatic zones where the temperature ambient ranges between 20⁰C to 40⁰C and the rain fall/humidity factors are moderate. We are fortunate enough that India is geographically located in tropical zone. This classic location advantage of the country in the world geographical map helped the country in keeping India as number one milk producer in the world, no 3 producer in poultry egg production, number 5 in horticulture production i.e fruits and vegetables. Climate change affects livestock both directly and indirectly. Direct effects from temperature, humidity, rainfall, wind speed and other climate factors, aggravates the heat stress in dairy animals, and influences animal performance badly: in growth factors, milk production in Dairy animals, mutton production/ wool production in case of sheep. egg and meat production in poultry, and reproductive aspects in all the species. The indirect impact of these factors on livestock may result on economic, nutritional and health aspects of human society and also its contribution to the economy of the country.

Rearing poultry industrially is a necessity in the present condition where the demand is high and the land holdings for extensive rearing is diminishing. All over the world the poultry industry is growing rapidly. The poultry industry in India is growing at around 8 per cent per annum. The poultry population of the country mainly consists of chicken, ducks, quails, ornamental birds and ratites. Chicken form is the major component of the industry. They are mainly reared as broilers for meat purpose and as layers for eggs. The climatic variations and their effects on profitable poultry rearing are an important topic of study in the current situation, where intensive rearing and global warming are being discussed with equal importance. The welfare aspects of the birds are also a matter of concern all over the world. Thus the knowledge of normal physiology of poultry, the effects of the tropical climate on them and the measures to alleviate detrimental effects produced by adverse climatic conditions have been discussed in detail here.

Sheep and goats in temperate regions are seasonal breeders with breeding activity mostly restricted to short day seasons of the year (Maule 1962). Endocrine mechanisms regulated by the variations of the day length stimulate reproductive activity to have maximum conceptions during the period of shorter days and correspondingly maximum births during longer day periods after a 5 months gestation (Hafez, 1987). Thus, essence of seasonal breeding is to ensure maximum births during the period congenial for survival of young ones, including availability of feeding materials and favorable climate. In tropical regions with minimum variation of day length and less distinct seasons, feed availability is not much affected by seasons in particular. Hence most species of animals maintains reproductive activity throughout the year (Devendra and Burns 1983). However there found to have influence of various locally relevant factors affecting comfort of living such as feed availability, weather and other environmental factors. Accordingly, there occur seasonal peaks and periods of restricted reproductive activity and pattern of the same can vary according to the local situations prevailing year to year (Goel and Agarwal, 1988 and Wani et al. 1980).

Climate change in particular global warming affect the health of the animals both directly and indirectly. Direct effects include temperature associated diseases like heat stroke and death and morbidity of animals during extreme weather conditions. Indirect effects include those deriving from attempt to adapt to changing environment or influence of climate on microbial populations, distribution of vector borne diseases, host resistance to infectious agents, feed and water shortages or food borne diseases. Among infectious diseases vector borne diseases and diseases caused by agents who have a stage in the environment are more likely to be affected than other diseases. The assessment of impact of climate change on animal diseases is challenging because there are several factors affecting the disease dynamics. But once the risk of potential diseases and their transmission routes are identified, the disease forecasts can be generated and control measures can be implemented to reduce the risk of such diseases.

Entrepreneur

The word “Entrepreneur” is derived from the French verb ?Entreprendre?. It means ?to begin something? or ?to undertake?. In the early 16th century the Frenchmen who organized and led military expeditions were referred as ?Entrepreneurs?. In the early 18th century French economist Richard Cantillon used the term entrepreneur to business. Since that time the word entrepreneur means one who takes the risk of starting a new organization or introducing a new idea, product or service to society. An entrepreneur is a person who starts an enterprise. He has right to own his business and to make a profit. Some economist says that entrepreneur is one who is willing to bear the risk of a new venture if there is a significant chance for profit. Others emphasize the entrepreneur?s role as an innovator who markets his innovation. Still other economists say that entrepreneurs develop new goods or processes that the market demands and are not currently being supplied. Different researchers have elaborated qualities of Entrepreneurs. Schumpeter said that entrepreneurs are innovators who use a process of creative destruction of the established ways of creating/doing existing products and services, to set up new products, new services. David McClelland proposed that an entrepreneur is a person with a high need for achievement. He is energetic and a moderate risk taker. Peter Drucker said that an entrepreneur searches for change, responds to it and exploits change as an opportunity. In the words of Albert Shapero, Entrepreneurs take initiative, accept risk of failure and have an internal locus of control. Entrepreneurship as explained by various scholars laid emphasis on a wide spectrum of activities such as self employment of any sort, creation of organizations and innovation.

Livestock entrepreneur is a person who undertakes livestock based activities such as livestock rearing, production of livestock/ livestock products, processing and other inputs of livestock business. He finds ways and means to create and develop a profitable livestock business. Livestock entrepreneurs see their farming as a business and as a means of earning profits. So they are willing to take calculated risks to make profits and to grow their businesses. They are also motivated to improve livestock production through mechanization and application of technologies in the field of dairy, small ruminant, poultry and allied enterprises. Livestock entrepreneur is determined and creative person, always looking for opportunities to improve and expand his business. He likes to take calculated risks, and assumes responsibility for both profits and losses. An entrepreneur is passionate about growing his business and is constantly looking for new opportunities.Enterprising farmers are also innovators. They always look for better and more efficient and profitable ways to do things. Being innovative is an important quality for a farmer-entrepreneur, especially when the business faces strong competition or operates in a rapidly changing environment. They look for better ways to organize their farms. They try, better animals, and alternative technologies to increase productivity, diversify production, reduce risk and to increase profits.

Techno economic feasibility of livestock enterprises under different conditions

The technical and economic feasibility part examines the possible technical and economic aspects of a proposed livestock project. In this chapter we would be studying techno economic feasibilities of various livestock based enterprise

1. Technical and Economic Feasibility of a Dairy unit

2. Technical and Economic Feasibility of a Goat Farm

3. Technical and Economic Feasibility of a Pig Farm

4. Technical and Economic Feasibility of a Feed unit

Once entrepreneurship is decided upon, there are three main routes an entrepreneur may follow. He can start a new livestock business, he can also purchase an existing livestock business or he can take over a family livestock business. In the first case the entrepreneur begins from scratch on all his own ideas, as there are no existing problems or concerns from a previous owner. He has the freedom to start the business in his own way. However, the risk is higher and he has to devote time, effort, and money—especially for startup expenses such as equipment, building, etc. When the entrepreneur purchases an existing business he has advantages of smaller startup costs and building on the existing goodwill or loyalty of established customers. This option is good if the entrepreneur does not have a great deal of business experience. Disadvantages might include inheriting existing problems such as poor location, stiff competition, fluctuating market, equipment problems, and poor reputation. In the third instance an entrepreneur takes over family business. In this situation, an entrepreneur has the support and training available from the family members, creating trust and togetherness that bonds the business as one entity. Maintaining separate family and business relationships is the biggest obstacle to overcome, making it difficult to get away from the business. Personality conflicts, different interests, changed values, and burnout are a few reasons that familyowned businesses don?t survive to the second generation. A person who grows up in the family business may be ready to spread his or her wings and explore new career aspirations.

Demand of livestock products is on the rise in India. India?s demand forecast for milk, mutton, egg production is more than the current supply of these products. To meet this demand entrepreneurship initiatives are need of the hour .Further, younger generation of India seems more interested in commercial dairy farming rather than subsistence based farming. Therefore, entrepreneurial training to farmers is essential. An average entrepreneur faces several barriers to start a new enterprise. Some of them are as under

Setting up livestock enterprise be it a small dairy unit, goat unit, milk and meat processing plant, selling parlor requires capital. Lack of access to credit to expand the herd is a critical problem for farmers. There is little access to formal credit through the cooperatives or banks. Informal credit is available from private traders and agents of private companies, but the interest rate is very high. Keeping this situation in mind and to provide financial support from banks few major dairy entrepreneurship schemes have been developed and implemented by banks with the support of state animal husbandry departments across different parts of the country. National Bank on Agriculture and Rural Development (NABARD) is the lead bank for financial support of such schemes.

Expectations from Veterinarian as Extension Officer to Promote Entrepreneurship

The veterinarian has to act as facilitators to exchange experiences, share knowledge and information and participate in joint problem-solving. This requires linking farmers with the right support institutions and individuals who have expertise to deal with their specific concerns. Therefore, extension workers need to understand the training needs of the farmers and to identify the best trainers or training institutions to meet those needs. Part of this involves creating awareness about the training programme and explaining the objectives and content to potential trainees.

Extension workers should also assess the impact of the training on the behaviour of the participants and on the farm business Impact assessment is essential because it is the true indicator of the relevance and effectiveness of the training programme.

Extension workers can also provide more general support in the form of study visits, study tours. Farmers observe ?good entrepreneurial practices?, and learn from the practices of others. Farmers are taken on a tour. See markets first-hand, visit input suppliers and buyers, and make contacts. Farmers also visit farmers in other areas to exchange experiences and see new techniques. Such visits can transform a farmer?s view on production and marketing. Visits should be followed up with periodic evaluations to assess the impact of the visit and the use of new practices and techniques. They can also arrange seminars with possible topics like entrepreneurship, farm business management, market possibilities, successful case studies, new technologies, price assessments and market-oriented production techniques. Extension workers can also facilitate farmers working with producer organizations. Producer organizations can make useful contributions to developing entrepreneurship among farmers.

Livestock rearing is central to livelihoods and survival of millions of people of India. It is estimated that approximately 100 million people derive their livelihood from livestock rearing as primary or secondary source of income. Livestock related activities help to maintain regular in flow of income for these households. Small farmers in India generate nearly half of their income from livestock and the value of cattle represents a significant part of their wealth, so the death of cattle poses a significant risk and affects farmers? net worth and income.

Type of Risks to Livestock based Livelihoods

Large animals are expensive and thus carry higher risk exposure. These risks are in form of losses due to the disease, accident, theft, natural calamity which can cause significant losses to these households. Sometimes owners are forced to sell their animals due to incurable disease/ disorder/ fodder and water scarcity and later they are unable to rebuild their stock. Many times animal losses force them into poverty trap from where they are unable to recover.

Livestock rearing provides triple benefits of income, employment and nutritional security to the society and is important source of subsidiary income to small/marginal farmers and agricultural laborers. Finance is a prerequisite and of paramount importance for setting up of a livestock enterprise whether a dairy farming unit for milk production, sheep or goat unit, piggery unit, dairy/poultry processing unit etc. Provision of credit/loans for the purchase of livestock, feed, veterinary services and insurance against the loss of valuable productive assets play an important role in encouraging new investments in the sector and also in coping with difficult problems such as draught and diseases. Decisions about credit are often most important judgments that people in the livestock enterprise must make. These decisions often determine whether individuals operating in input, production, processing and services based livestock enterprise would succeed in making profit.

Project Appraisal : Assessing Project Benefits

Project appraisal helps to determine which among various projects one is to accept and which to reject. This is however possible only when costs and benefits have been identified, priced, and valued. A number of techniques of project appraisal can be discussed under two heads :

Marketing channel can be defined as the path that a livestock commodity follows from the farmer?s gate to the consumer?s plate. A marketing channel involves a set of separate but interdependent organizations involved in the process of making a product available to consumers.

Importance of Marketing Channels

1. Little attention by companies or enterprises to marketing channels may damage profit, brand and number of customers.

2. Companies can change their products, advertising and pricing easily but it is not easy to change marketing channels.

3. Marketing channels are particularly convenient when the producer does not have time or financial means to carry out direct marketing.

4. Intermediaries in marketing channels are usually able to make the product widely available and accessible because they are specialized, have experience and contacts. They also have a better understanding of the market. Intermediaries take the risks involved in marketing and also pay for the produce immediately.

Standardization

Standardization means establishment of standards for matters such as quality, size, weight and color. Once standards are set grading is possible using the criteria established in the standards. Thus, standardization involves establishment and maintenance of uniform measurements of produce quality and/or quantity.

Grading

Grading follows standardization. It is a sub-function of standardization. It is a method of dividing products into certain groups or lots in accordance with predetermined standard. Grading before sale enables farmers to get a higher price for their produce .Consumer get standard quality products at fair prices. It is easier for them to compare the prices of different qualities of a product in the market. It minimizes their purchasing risk, for they will not get a lower quality product at the given prices .e.g. eggs are graded into different categories based on set standards. Similarly cattle feed is also sometimes categorized into different grades based on established standards.

Sales management as the term implies means management of sales. Initially the concept consisted of managing the sales workforce. Now-a-days, it includes managing of all the sales related activities like advertising, sales promotion, physical distribution, pricing and product merchandising.

Abstract

The article briefly narrates the initiatives taken by the Department of Science and Technology, Govt. of India, New Delhi in providing solutions to rapidly growing Landslide Disasters in India. Duly considering the importance of the issue, the DST has embarked on a National Landslide Programme more than two decades ago and brought voluminous information on Landslide Vulnerability Mapping, Site Specific Landslide Investigations, Landslide Kinematics, Instrument Based Forewarning etc. by funding large number of research projects to various Academic/Research institutions in the country. In addition, the bilateral collaborative programme launched on Geohazards between India & Norway, resulted in bilateral flow of knowledge and capacity building amongst various tiers of the Academic, Research and the Planning Hierarchy, yielding tangible benefits.

Keywords: Landslides in India, DST’s Initiatives.

INTRODUCTION

Landslides cause extensive damages to roads, bridges, human dwellings, agricultural lands, forests and other establishments year after year resulting in immense losses of life and properties. The entire Himalayan region has been the target of intense development activities for the last few decades. Hence the instabilities along the natural slopes are accentuated by the human activities since the development schemes are often not properly planned and implemented (Valdiya 1980; Thakur 2001). This has become the case in most of the mountains in India. Keeping in view of the stability of the slopes, the need of the hour is to achieve sustainable development of the hilly regions while implementing various developmental schemes. So there has to be a major S&T role to play to minimize the landslide problems. This should include all possible corrective and preventive measures to minimize the losses due to this disaster.

Abstract

Landslides have become a recurring phenomenon in most of the mountainous regions of the world. In Indian peninsular, the landslides which were mostly confined to the tectonically active Himalayan Mountains once, have started spreading over to the other mountain belts of the Peninsula. The Tirumala – Tirupati hills, which is drawing millions of pilgrims from all over the world is facing landslides especially along the newly built southern uphill ghat road. The geology of the area, studied using Geomatics tools like Remote Sensing, SRTM based Digital Elevation Models, GPS Survey, etc., showed that Tirumala hills is under the grip of upward tectonic movements as evidenced from the N-S and E-W oriented Pleistocene faults, intensely dissected Plateau top Cuddapah Quartzites, retreating escarpments, exhaustive debris slope, extensive valley fills along the slopes, colluvial fills in lower slopes, palaeo debris flows along the southern and western obsequent slopes of the Tirumala hills etc. All these indicate the inherent landslide vulnerability of the slopes. The E-W trending dykes which are piercing the slopes and protruding as ridges add further landslide vulnerability to such fragile slopes. So, the new ghat road laid along such southern slope is obviously facing landslides. However, the detailed Geomatics based studies show that the dykes, valley fills and steep slopes are particularly more vulnerable to landslides. Though remedial measures have been broadly evolved, abandoning the southern uphill new ghat road and widening the older northern downhill ghat road seems to be the better and long term feasible alternative to prevent Landslides in the area.

Abstract

Northeastern part of the Indian subcontinent is seismically an active region, and is further prone to excessive rainfall and frequent landslides, which cause disruption of the road networks during the monsoonic months every year. The region owns a typical morphotectonic setup where many active thrusts and faults have carved out the landforms and physiography of the major part of the region. The creeping phenomenon of the N-S trending prominent strike-slip fault, namely the Churachandpur - Mao Fault (CMF), is one of the triggering factors for the frequent landslides and low magnitude earthquakes. The life line of Manipur, the national high way NH39, traverses along and in close proximity to this fault in Manipur, and hence the life is paralysed in the area during the monsoonic months. From the GPS campaign mode studies on the western and eastern sides of the CMF, it is observed that there is a change in the crustal velocities from 16 - 22 mm/yr in the east to 33 - 42 mm/yr in the west. Micro-deformations are also observed in the form of displacements respectively with the vertical, N-S and E-W components of–0.111 mm/yr (downward), 0.03 mm/yr (northward) and –0.011 mm/yr (westward). The net displacement is 0.126 mm/yr with an azimuth of N 85° and dipping of 13° towards west. Neotectonic movements along the CMF, as per the GPS measurements, suggest an aseismic nature of the fault with dextral component. Fault plane solutions of the earthquakes show northerly directed principal P-axis indicating the extension (T-axis) along east-west. The resultant creeping of micro-deformation towards the western slopes of the terrain is aligned with the principal T-axis. The creeping triggers the micro seismicity as well as the landslides along the CMF.

Abstract

The Sonapur landslide located in the south eastern fringe of Shillong Plateau falls in NH44 connecting Shillong with Agartala. The slide is repeatedly active and massive debris flows occur during every monsoonic season since 1999. The studies carried out under the NRDMS funded project shows that the slide falls in the tectonically active E-W Dauki fault system, which not only forms the southern boundary of the Shillong plateau but also the near vertical plane along which the Shillong plateau has been uplifted due to the northerly compressive force and the collision of Indian plate with Eurasian plate. Such post collision tectonic uplift and the southerly tilt of the Shillong plateau in its southern part, monoclinal southerly dipping sediments south of Dauki fault, Sylhet trough, occurrence of NE-SW sinistral (shears) and NW-SE dextral faults in Sonapur area, high seismic activity and rainfall are responsible for the Sonapur Landslide.

Abstract

The landslides have become the fast spreading disaster all over the Indian sub-continent. As such landslides were mostly occurring in the Mighty Himalayan Mountains, it was all along attributed to active tectonics. But when it started occurring in most of the mountain belts of India, various geological parameters, the anthropogenic phenomenon and rain fall were inferred to be the main causes for the landslides. Hence when this concept emerged, and again the Remote Sensing and the GIS technologies have phenomenally evolved, different types of variables, again on different resolutions and different methodologies have been adopted to prepare landslide vulnerability maps and this has started yielding varying types of outputs. As the landslide vulnerability zonation mapping (LVZ) is the first step in landslide studies it is essential to evolve a suitable methodology for the same. So the present study was carried out in a test site of around 300 sq.km in between Coonoor and Otacamund, Nilgiri mountains, Western Ghats, South India. In the said study, a set of 12 Earth System Parameters/Variables which could contribute to landslide vulnerability were prepared as GIS raster databases from the data interpreted from satellite MSS data and field geological and geophysical data sets. Similar GIS database was generated on 144 landslides. These landslides were superposed over such 12 Earth system parameters data and landslide vulnerability weightages were assigned to each subvariables of these Earth system parameters. In assigning weightages using such landslide incidence data various methods viz; slope, integrated terrain, information value, weight of evidence, index overlay and BIS methods were used and landslide vulnerability zonation maps were prepared adding all the 12 weightages assigned Earth system variables. In this, all the 12 earth system parameters were having same resolutions. Then the outputs were compared which revealed that the information value method is the best suited method for LVZ mapping followed by weight of evidence method.

Abstract

Prediction of the occurrences of Landslides requires a set of complex analyses, involving multitude of factors which are to be studied systematically in order to evaluate the landslide vulnerability. The increasing availability of computer-based tools and data storage capabilities are found to be useful in landslide vulnerability mapping. One such significant tool in landslide studies is Geographic Information System (GIS). In this article some approaches were made to model the land slide hazard for Sirumalai Hills, Dindigul District, Tamil Nadu, India using Geographical Information Systems and the same is presented in this paper.

Abstract

Landslides are the most common hazards in hilly regions. Rapid development and the resultant uncontrolled interactions with ecosystems are the major reasons for the landslides, besides the rainfall. So, the assessment of landslides hazard vulnerability is a prerequisite before making any developments related to settlements, hill resorts, hydropower projects and the related network of Ghat roads. The present study deals with the assessment of landslides in two different sites; Site-1 located in the Ghat section of Yercaud hills between 10/4 and 29/6 km stones in the southwestern slopes of Shevroy hills, Salem, and the Site-2 located in the Ghat road between Lower camp and Kumuli in Theni districts, Tamil Nadu. The Theni ghat road in the National Highway-220 is connecting Tamil Nadu with Kerala and is the lifeline for Sabarimala, Tekkadi and Munnar. Besides, a series of pan stacks conveying water from Periyar reservoir in Kerala to the power house located at Lower camp in Tamil Nadu also lie in this stretch of hills. Landslide vulnerability mapping was carried out in an area of 130sq.km in Site-1 and 6.7 sq.km in Site-2 by assigning numerical values to the causative factors of slope instability such as lithology, structure, slope morphometery, relative relief, land use and land cover, and ground water conditions following the BIS code No. 14496 (1998) for preparing landslide hazard zonation maps. The study in Yercaud hills revealed that out of 12 slope facets, facet 1 to 6, 9 and 12 fall under moderate landslide hazard zone whereas facets 7, 8, 10, and 11 fall under high hazard zone. The area falling in facets 3, 4 and 5 of Kumuli ghat section fall under high landslide hazard zone, the slope facets 1, 2, 9 and 10 fall in the moderate hazardous zone and other facets in low hazardous zone.

Abstract

Similar to other north eastern states of India, the state of Manipur is also prone to recurring landslides. The National Highway 150 and the state Highway in Ukhrul, Nunghar and Paorei sectors often witness landslides due to geological complexities, rainfall and anthropogenic activities. So a study was conducted to prepare the landslide hazard zonation map for the region using the method developed by Bureau of Indian Standards, which indicates that 67.32 km² (nearly 56%) fall under high hazard zone. The RMR and SMR studies carried out in five test sites in such high hazard zone show that four sites fall under highly unstable category (class IV) and one under partially unstable category (class III). The kinematic analysis indicates dominant wedge failure. The improper landuse, lack of adequate drainage and toe removal for road widening are the major causative factors for the recurring landslides.

Abstract

The softer rock types belonging to Tertiary period, intense deformation and the related more frequent tectonic weak planes, high degree of weathering and extensive road cutting are the inherent systems in provoking Landslides in Noney-Nungba segment of NH-53 in the state of Manipur. So Landslide Hazard Zonation mapping was carried out in this segment using BIS method and also geotechnical investigations were carried out in Awang Khull part-II slide and Raungdai slide and on the basis of type of failure and the morphotectonic conditions mitigation strategies were suggested.

Abstract

The state of Nagaland located in the northeastern part of the Indian subcontinent is also prone to landslides similar to the other north eastern states due to the softer lithologies, intense deformation and extensive anthropogenic activities. So in order to understand the landslide vulnerability and to evolve remedial measures, a 12 km stretch of the NH-2 from Kohima town in the south to Zhadima junction in the north was studied. The study comprises the preparation of landslide hazard zonation map using BIS method and detailed studies in six major landslides involving RMR, SMR and Kinematic analysis and also the suitable remedial measures for such landslide phenomenon.

Abstract

Due to fragile lithology belonging to Disang and Barail groups of the Cretaceous-Tertiary period, intensive structural deformation related to collision tectonics, extensive weathering and the anthropogenic activities in the form of slope cutting for the development and widening of roads lead to frequent landslides in the state of Manipur, India. In this connection, the road section between Tengnoupal and Sita has been studied to understand the landslides vulnerability and to evolve mitigation strategies. The study involved the Petrochemical analysis to elucidate the weathering potential of the rocks, kinematic analysis to understand the network of joints and the strain, slope stability analysis to prepare Land Hazard Zonation mapping and estimation of factors of safety in selected locations. On the basis of these studies, long & short term remedial measures were suggested to mitigate the landslide hazards.

Abstract

Geological conditions in the Tertiary mountainous areas of the western and eastern hill ranges of Manipur often cause landslide movements. These repeatedly occur mostly in old landslide regions during rainy seasons on a large scale, causing considerable economic loss and injuries and deaths of humans. In order to improve such landslide hazard assessment of the region for effective mitigation, Electrical resistivity surveys were conducted using Schlumberger array technique on the very unstable and problematic frontal part of the Kotland landslide, NH-37, Manipur along three profiles. Electrical resistivities aided the characterization and quantification of the subsurface rock units, structure and tectonic conditions of the Landslided area which can contribute for the better planning of mitigation strategies. The results lead to the elucidation of depth of the different litho-units and the geometry of failure surface. The probable failure surface was observed between 10 and 22m depth, characterised by low resistivity (< 150 Ωm) and geometry of the sliding surface was rotational. In addition, a fault was also inferred in the resistivity pseudosection model and hence the area may be highly vulnerable to landslides.