eChapters

Introduction

Arid lands are among the world’s most fragile ecosystems, made more so by periodic droughts and increasing over exploitation of meagre resources. Arid and semi-arid lands cover around one-third of the world’s land area and are inhabited by about one billion people, a large proportion of whom are among the poorest in the world (Malagnoux et al. 2007). Arid environments are extremely diverse in terms of their land forms, soils, fauna, flora, water, and human activities. Aridity is usually expressed as ratio of mean annual precipitation (P) to the mean annual potential evapotranspiration (EPT) where potential evapotranspiration is calculated by method of Penman, taking into account atmospheric humidity, solar radiation, and wind speed. UNEP (1997) has recognized four main classes of aridity: hyper-arid (P/EPT < 0.03), arid (0.03 < P/EPT < 0.20), semi-arid (0.20 < P/EPT < 0.50), and dry sub-humid (0.50 < P/EPT < 0.65). Of the total land area of the world, the hyper-arid zone covers 4.2 %, the arid zone 14.6 %, and the semi-arid zone 12.2 % (FAO 1989). Therefore, almost one-third of the total area of the world is “arid land”. 

Introduction

India has a long tradition of agroforestry which is widely practiced in all ecological and geographical regions of the country. Traditional agroforestry systems are broadly based on indigenous knowledge and the species are selected as a part of the cultural patterns of the community. The farmers and land owners in different parts of the country integrate a variety of woody perennials in the crop and livestock production systems depending upon the agro-climatic conditions and local requirements.

Introduction

Two types of interactions, i.e. competitive and complementary, are found in ecosystems and agroecosystems (Callaway 1998), which shape community structure, plant diversity and system’s functions (Callaway 1995; Pugnaire et al. 1996; Bruno et al. 2003). Competitive interaction in ecosystems (Wedin and Tilman 1993) and agro-ecosystems (Pandey et al. 1999) is well documented. Mechanism of complementary interaction, however, is not much understood so far. Some studies (Bertness and Callaway 1994; Callaway 1998) argue that complementary interaction is facilitative, either facultative or obligatory, and occur generally in harsh physical environments. This suggests that habitat amelioration by neighbours is a common denominator of positive interactions (Bertness and Callaway 1994; Callaway and Walker 1997). Other studies report that complementary interaction is mutualistic (Boucher et al. 1982). Irrespective of whether facultative or mutualistic, it is now well established that complementary interaction is evolutionary (Bertness and Callaway 1994). But, it is still inconclusive how two species exist together in ecosystems and agroecosystems (Bertness and Callaway 1994).

Introduction

Human civilization used to undergo several form of disasters throughout its life history. Most of such events are unpredictable, sudden and short in duration, and such events can easily classifiable as either natural (e.g. cyclones, earth quake, natural forest fires and tsunami) or manmade such as spread of toxic chemicals (e.g. Bhopal disaster 1984), nuclear explosions, civil war, diseases (Minamata, itaiitai, etc.). However, climate change is a real time prolonged disaster which is caused by both natural (caused by variation in solar irradiance, variations in orbital parameters of earth, volcanic activities, natural forest fire, methane release from thawing of permafrost from ocean floor, natural wetlands and cattle) and anthropogenic means (by greenhouse gases resulted from human activities-all kinds of combustion, industrial production of greenhouse gases and agricultural water lodging activities such as paddy cultivation and artificial wet lands, and deforestation).

Introduction

Throughout the arid zones, there is no dearth of problems, but rapidly increasing desertification (some call it land degradation) is a problem of worldwide dimension. Water is a scare commodity in arid zones. Much of rainfall is lost by evapo-transpiration and as a result, ground water recharged only by seepage through soil profile. However, it is a common phenomenon in arid zones of the world that ground water is frequently used at the rate that exceeds recharge. The situation in arid tropics of India, which is spread over an area of 31.7 million ha, is no more different. Considering the role of agriculture in the social and economic progress of developing countries, the vulnerability of agricultural systems to the impacts of climate change has received considerable attention from the scientific community (Fischer et al. 2002; IISD 2003; Kurukulasuriya and Rosenthal 2003). Much of the available literature suggests that the overall impacts of climate change on agriculture especially in the tropics will be highly negative, although in a few areas there may be minor increases in crop yields in the short term (Maddison et al. 2007). Research on agroforestry as an adaptation to climate change and as a buffer against climate variability is in the process of evolving.

Introduction

Rain fed agroecosystem occupies 68% of India’s cultivated area and supports 40% of the human beings and 65% of the livestock population. It produces 44% of food requirements, thus has and will continue to play a critical role in India’s agriculture (Singh et al. 2004). Besides their well established role in agriculture, livestock have crucial role in food security and as risk aversion mechanism for sustaining family, whenever there is crop failure. Indian hot arid zone which is about 12% of total geographical area of the landmass of 0.32 million km2 has maximum covering in western Rajasthan i.e. 61% of the total area whereas the other areas in arid region are available in the states of Gujarat, Punjab, Haryana, Andhra Pradesh and Karnataka accounting for 20, 5, 4, 7 and 3% of hot arid area whereas the cold arid area of 8.4 million ha lies in the state of Jammu & Kashmir covering the Leh and Ladakh region.

Introduction

A number of researchers have used morphological descriptors such as growth habit, leaf, shoot, flower, fruit morphology to classify and discriminate different varieties/cultivars and or detect inter and intra-specific variations in different tree species of economic importance (Saran et al. 2006; Holland et al. 2009). Such morphological descriptors are quite homogenous and often found insufficient to distinguish varieties within morphological groups. The choice of suitable cultivars is of paramount importance for its success. The lack of breakthrough has been due to under utilization of genetic variability for superior quality and high yield potential. Most of the fruit tree species demonstrates a rich genetic diversity mainly through natural cross pollination due to self incompatibility (Godara 1980). The elite plant types with desirable traits have been released as varieties, mass multiplied and propagated through standard vegetative multiplication. However, the authenticity of cultivar identification remains unclear (Devanshi et al. 2007).

Introduction

The area under salt-affected soils in India is estimated to be 6.73 Mha spread over a number of states across the country. This 6.73 million ha are lying barren or produce very uneconomical yields of crops due to excessive accumulation of salts. These soils are agriculturally unproductive because of the high content of soluble salts which had harmful effects on plant growth due to moisture stress and toxicity/deficiency of some of the ions and the exchangeable sodium ions in clay complex lead to the unfavorable physical conditions of for the plant growth and water movement (Bhumla 1977). Saline and sodic soils have excess concentration of either soluble or exchangeable sodium, calcium and magnesium primarily in the form of chlorides and sulphates. Salt affected areas an expected to increase with spread of waterlogging and salinity due to increase in canal irrigation, and intensive exploitation of poor quality ground waters for agriculture in non canal commands. Certain states like Rajasthan and Haryana located in the western part of the country are endowed with 84 and 62% of poor quality ground waters, respectively. Continuous use of such waters for irrigation to agricultural crops is bound to increase the problem of salinity and sodicity in India (Yadav 1989; Minhas and Bajwa 2001). Introduction of irrigation without making proper provision for drainage is the major cause for the development of salinity in canal commands.It is severe on irrigated lands of the dry zone. It reduces crop yield and in severe cases causes complete abandonment of agriculture (Joshi and Dhir 1989; Joshi et al. 2000; Mahesh Kumar et al. 2016). The present paper deals with extent, causes, characteristics and management options of these soils for sustainability of agriculture in the area.

Introduction

Desertification is affecting the livelihoods of millions of people, mainly poor in the dry lands, which occupy nearly 41% of the Earth’s land area and are the residence of more than 2 billion people of the world. In India, the western part of Rajasthan is mostly affected by desertification process dominated by wind erosion. Kar et al. (2009) reported that 15.2 mha land in western Rajasthan is affected by wind erosion out of total 22.96 mha area under desertification. A brief account on issues and priorities related to wind erosion processes in Thar desert was reported in Santra et al. (2006). Plenty of incident solar energy in the region makes the desert surface very hot especially during summer months. Wind speed also remains very high in the region for most of the time in a year. Therefore, the loss of top fertile soils through wind erosion process is very active in the region. Eroded dust particles during severe wind erosion events commonly known as dust storms not only create the soils poor but also pose several environmental threats through generating aerosols in atmosphere. 

Introduction

The world demand for wood is continuously increasing due to increase in population. The ever increasing population has led to depletion of existing timber reserves and the forestland base has been reduced by increased allocation of forest areas to urban, agricultural, recreational and other uses. The growing awareness towards development of plantations has generated a voluminous increase in the demand for quality planting material. Conventionally, propagation is achieved through sexual (seeds) or vegetative methods (rooting of cutting, grafting, layering, etc). Propagation through seeds is routinely used for production of planting material but it generates immense genetic variability which is not desirable while propagating perennial tree species. In order to propagate selected trees with desirable features vegetative propagation methods like rooting of cuttings, grafting, layering etc have been developed. These methods can produce genetically identical off springs thereby preserving the advantageous traits;

Introduction

Trees play an important role in ecosystem in all terrestrials and provide a range of products and services to rural and urban people (Gogoi 2015). As natural vegetation is cut for agriculture and other types of development, the benefits that trees provide are best sustained by integrating trees into agricultural system - a practice known as agroforestry. Agroforestry focuses on the wide range of trees grown on farms and other rural areas. Among these are fertilizer trees for land regeneration, soil health and food security; fruit trees for nutrition; fodder trees for livestock; timber and energy trees for shelter and fuel wood; medicinal trees to cure diseases and trees for minor products viz. gums, resins or latex products. Many of these trees are multipurpose, providing a range of benefits. Although effective and valuable tools have been introduced to evaluate the risk to construction in areas prone to geo-hydrological hazards, fewer steps have been made in the field of ordinary land use planning at different scales. 

Introduction

There is a growing interest in the role of different types of land use systems in stabilizing the atmospheric CO₂ concentration and reducing the CO₂ emissions or on increasing the carbon sink of forestry and agroforestry systems. Forestry has been recognized as a means to reduce CO₂ emissions as well as enhancing carbon sinks. There is considerable interest to increase the carbon storage capacity of terrestrial vegetation through land-use practices such as afforestation, reforestation, and natural regeneration of forests, silvicultural systems and agroforestry (Brown 1996; Canadell and Raupach 2008). Agroforestry systems are very important given the area currently under agriculture, the number of people who depend on land for their livelihoods, and the need for integrating food production with environmental services (Garrity 2004; Makundi and Sathaye 2004).

Introduction

Agroforestry is a land-use management system where trees or shrubs are grown around or among crops or in pasture lands. It combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy, and sustainable land use systems.
India has been at the forefront of agroforestry research ever since organized research in this area started worldwide about 25 years ago. Considering the country’s unique land use, demographic, political and socio-cultural characteristics as well as its strong contributions to agricultural and forestry research, India’s experience in agroforestry research has proved important to agroforestry development especially in developing countries.

Introduction

The literatures and researcher data showed that there is negative impacts of agricultural expansion, landscape modification and deforestation on biodiversity, ecosystem services, alteringthe species composition and their ecological functions (Tscharntke et al. 2005; Priess et al. 2007; Flynn et al. 2009; Senior et al. 2013; Deguines et al. 2014; Kumar 2016) which can lead to considerable changes in critical ecosystem processes. On the other hand, an increasingly industrialized global economy, rapid population growth, land degradation, land use pattern and role of various human activities have led to dramatically increased the pressure on the natural resources such as the available land for sustaining the livelihoods, and with over exploitation and extraction of the natural resources the ecosystems are becoming unsustainable and fragile since last century (Kumar 2017). Standardization of cultural practices is one of the primary objectives to make the system ecologically, sustainable and economically viable (Gill et al.2009).

Introduction

Forest cover of India has been estimated to be 7,01,673 km2 (70.17 million ha) which is 21.34 per cent of the total geographical area of the country. The tree cover of the country is estimated to be 92,572 km2 which is 2.82 per cent of geographical area. The total forest and tree cover is 7,94,245 km2 which is 24.16 per cent of the total geographical area of the country. Out of this, 9.14per cent forest cover is in the form of open forests and another 1.26 per cent is scrub forests (FSI 2015). According to National Forest Policy 1988, one-third (33.33%) of the land area should be under the forest cover for sound ecological balance. It means that we have to bring another 11.66 % area under forest cover and at the same time improve quality of the degraded forests. However the horizontal expansion of land under tree cover is not possible. In order to increase the tree cover and fulfill the requirements of the people and industries,

Introduction

Homegardens are traditional agricultural systems, particularly common in the tropics characterized by a high plant diversity (Kumar and Nair 2004, 2006; Scales and Marsden 2008; Galluzzi et al. 2010), maintain high level of productivity, stability, sustainability and equitability (Soemarwoto and Conway 1992), serve as a refuge for wildlife (Perfecto and Vandermeer 2008), contributing significantly to the household diet by producing a large variety of food commodities (Kumar and Nair 2004; Wiersum 2006; Pulido et al. 2008; Kortright and Wakefield 2011; Kumar 2017; Kumar and Tripathi 2017), nutritional supplies (Mendez et al. 2001; Perrault and Coomes 2008; Vlkova et al. 2010; Balooni et al. 2014), supplementary cash income for owner (Huai et al. 2011; Arifin et al. 2012; Yang et al. 2014) and important spaces for transmission of cultural heritage (Galluzzi et al. 2010). Many native or endangered species can be found in homegardens (Albuquerque et al. 2005; Akinnifesi et al. 2010; Milow et al. 2013), and they are niches for domesticating semi-wild species (Akinnifesi et al. 2010). Plants grown, intentionally or unintentionally, in homegardens are important for household subsistence and economy.

Introduction

Agriculture expanded and forest dwindled. That eventually occurred with the expansion of civilization. Clearing of forests, granted in past, continued in modern times. Cutting of forests reached to such an alarming level that thinking of people turned back to create more forests. Sometimes over extraction of forest resources made forests unstable to yield perpetually according to necessity in future for which forests are turned unsupportive for livelihood and people tried for innovative means to enhance forest productivity in future (Nair 1993). Also with time agriculture faced the similar unfortunate condition towards intensive cultivation. So, peoples’ thinking turned back in agriculture how to make it stable and more supportive for livelihood year after year. Culturally human societies are connected both with agriculture and as well as forests from the time immemorial.

In contrast to the earlier and existing non-sustainable land use practices, agro forestry presents a more dynamic, productive and sustainable solution to the increasing demand of food, fodder, timber and other agricultural and tree goods. According to the United Nations,the world population was more than 7 billion in 2011 which is expected to go up to 9.3 billion by the mid-century. Consequently food production needs to be increased by over 60% by the year 2050. Agroforestry, which is a multifunctional, ecologically based, natural resource management system can help in dealing with such environmental, economic or social issues.

Evidence over the past few decades has conclusively established that significant changes in climate are taking place worldwide as a result of enhanced anthropogenic activities. The fast pace of development and industrialization and indiscriminate destruction of natural environment, more so in the last century, have altered the concentration of atmospheric gases that lead to global warming. The major cause for climate change and global warming has been ascribed to the increased levels of greenhouse gases (GHGs) like carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), chlorofluorocarbons (CFCs) etc. beyond their natural levels due to the uncontrolled activities such as burning of fossil fuels, increased use of refrigerants, and enhanced agricultural related practices.

Introduction

Increase in atmospheric carbondioxide (CO₂) and other green house gases viz. methane (CH₄), nitrous oxide (N₂O) and CFC (Chloro-Flouro- Carbon) due to fossil fuel burning, rapid industrialization and deforestation, which reduces the amount of earth’s radiation, that escapes to space. Role of these gases to change in climate over a longer period of time is the key issue of climate change. Climate change is a change in climate over time, whether due to natural variability or as a result of human activity (IPCC 2007).

IPCC :The UNEP (United Nations Environment Programme) and WMO (World Meteorological Organization) jointly established IPCC (Inter-governmental Panel on Climate Change) to assess available scientific information on climate change as well as to study its impact during 1988. Since establishment, IPCC has produced five major assessment reports. According to IPCC, climate change is defined as a movement in climate system as a result of internal changes within climate or interaction among its components. Frequency of extreme events (viz. heat waves, intense rain, floods, droughts etc.) are reported to follow increasing trend. Fig.1 is showing natural climatological cycle in the earth throughout different seasons as various components of climate system (IPCC 1996).

Introduction

Agriculture is the mainstay of livelihood activity of about 70% of the state’s population. Madhya Pradesh is an agrarian state and the state’s economy is highly dependent on agriculture. Considering the sector’s sensitivity to climatic parameters it can be easily understood that the sector would be highly impacted by any change in these parameters.

Madhya Pradesh has a subtropical climate with three distinct seasons’ viz. winter from December to February, followed by summer season from March to May and rainy season extending from June to October. During winters the mean temperature remains around 10ºC and mean maximum temperature remains 25ºC and the minimum temperature goes down to 1°C in some regions. During summers, the mean minimum temperature is 22ºC and mean maximum is 38ºC. The maximum temperature during summer can go up to 48ºC, especially in May and June which are the hottest months.

Introduction

Climate is the primary determinant of agricultural productivity. Plant systems, and hence crop yields, are influenced by many environmental factors such as moisture and temperature, may act either synergistically or antagonistically with other factors in determining yields (Waggoner, 1983). In the recent years, climatic change/variability is a biggest challenging factor that affects agriculture in India and elsewhere and concern has been expressed by world community regarding the potential effects of climate change on agricultural productivity. Climate change is expected to influence crop production, hydrologic balances, input supplies and other components of agricultural systems. Agricultural systems are managed ecosystems. The climate change induced atmospheric stress will be the primary cause of crop loss worldwide, reducing average yields for most major crop plants. Environmental stresses such as erratic and insufficient rainfall, extreme temperatures, salinity, alkalinity, acidity, heavy metal toxicity, oxidative stress and others limit yield and productivity of many cultivated crop plants. Drought, extreme temperatures and oxidative stress are interconnected and affect the water relations of a plant on the cellular as well as whole plant level causing specific as well as unspecific reactions (Beck et al., 2007). This leads to a series of morphological, physiological, biochemical and molecular changes that adversely affect plant growth and productivity (Wang et al., 2001).

India has shown to the world that with 2.4 % of the land and 4 % of the water resources available at the global level, it can provide the food security to its millions. A record production of almost 265 million tonnes in 2013-14 is a testimony to the strides taken in the field of agriculture. However, the agriculture sector faces many new challenges in the future and climate change (global warming) is perhaps the most formidable one.

The new emerging demands of the relatively more-affluent Indian population, particularly its middle class, coupled with a net cultivated area unlikely to exceed 143 Mha in 2050 as well as an estimated rainfed agriculture to cover around 45 % of the net sown area, are further compounded with the harsh reality that highly productive agricultural land is being continuously lost out to the industry and urban sectors. How will the country meet the target of 400 Mt of food grain production is the mute question, in a situation where natural resource base is continuously degrading and climate change with its attendant impact is adversely affecting the agricultural production system (Singh, 2014).

Introduction

Rainfed agro-ecosystems occupy a considerable place in Indian agriculture, covering 80 M ha in arid, semi-arid and sub-humid climatic zones; constituting nearly 57% of the net cultivated area. Rainfed areas contribute almost 100% of forest products, 84-87% of coarse-grain cereals and pulses, 80% of horticulture, 77% of oilseeds, 60% of cotton and 50% of fine cereals including rice, wheat, maize, sorghum etc (Srinivasarao et al., 2010; 2011). Rainfed regions support 60% of livestock, 40% of human population and contribute 40% of food grains and several special-attribute commodities such as seed spices, dyes, herbs, gums, etc. (Srinivasarao et al., 2011). It is estimated that even after achieving the full irrigation potential, barring for successful completion of river linking project, nearly 45 to 50% of the total cultivated area will remain dependent on rain. Undoubtedly, the rainfed agriculture would continue to occupy a prominent place in Indian agriculture for a long time to come (Venkateswarlu et al., 2011). Despite the progress made so far, rainfed agriculture in India encounters multiple risks and constraints relating to biophysical and socio-economic issues. Agricultural productivity in rainfed areas continues to remain low and unstable due to weather aberrations, nutrient disorder and poor socio-economic status of farmers.

Introduction

Adoption of green revolution technologies during 1960s led to increased productivity and elimination of acute foodgrain shortages in India. These technologies primarily involved growing of high-yielding dwarf varieties of rice and wheat, increased use of chemical fertilizers and other agrochemicals, and spread of irrigation facilities. This was also accompanied by other modern methods of cultivation, which included maximum tilling of land, virtually clean cultivation with complete removal of crop residues and other biomass from the field, fixed crop rotations mostly involving cereals, and elimination of fertility- restoring pulses and oilseed crops in the highly productive north-western plain zone of the country.

Introduction

Agroforestry offers both adaptation and mitigation options to climate change especially for the poor rural communities in the developing world. It is now getting ample attention from different investors, scientists, policy makers and international bodies due to its multiple benefits to the environment; and remain an important component of sustainable land use in agricultural production. Agroforestry provides economic, environmental, and social security to the vulnerable communities who are dependent on agricultural production for their livelihoods, and on forest/ trees for their energy requirement. Agricultual production is vulnerable to climate change, and there is a need to cushion these communities to be less vulnerable to climate change, or natural hazards. The suitable, sustainable and smart method is agroforestry based agriculture which offer host of ecosystem services to cope the vagaries of climate change, particularly in rural areas.

Conservation Agriculture (CA) is defined as a process of ‘sustainable intensification of agriculture’ for enhancing and sustaining production at low cost, without deteriorating soil health and flow of environmental services. The process of agricultural intensification increases food production and spares land for the other uses including eco-system services. In line with the vision of Norman Borlaug, agricultural intensification is also known as ‘The Borlaug Effect’. Frameworks such as ‘Conservation Agriculture’, ‘Ecological Intensification’ and ‘Ever Green Revolution’ share a common view of cropping systems as agro-ecosystems designed to make maximum use of fixed resources (land, light and temperature etc.) with optimum use of agri-inputs for attaining sustainable production levels (Cassman 1999)’. Conservation agriculture is also considered as an important component of the overall strategy for ensuring food security, poverty alleviation, health for all, rural development, enhancing productivity, improve environmental quality and preserve natural resources. With limited scope for further expansion of area under agriculture, production gains can be accomplished through intensification of agriculture, achieved by pursuing one or more strategies (with rationale use of natural resources as well as external production inputs) enumerated as under:

Climate change is a statistical variation in properties of the climate system that includes changes in global temperature, precipitation, etc due to natural or human drivers over a long period of time. It may affect distribution and quality of natural resources thereby influencing livelihood security of the people (Status of Indian Agriculture, 2013). Recent climate change activities is the increase in earth’s temperature by 0.74^ºC between 1906 to 2005 (IPCC 2007) due to increase in anthropogenic emissions of green house gases such as carbon dioxide (CO₂), methane (CH₄), ozone (O₃), nitrous oxide (N₂O) and chlorofluorocarbon (CFCs). Increase in concentration of green house gases influence future climate as well as agriculture (Mall et al., 2006; IPCC, 2001; Aggarwal, 2003: Bhatia et al., 2004). For Indian region under South Asia, Intergovernmental Panel on Climate Change (IPCC), 2007 projected a rise in temperature from 0.5-1.2^ºC by 2020, 0.88-3.16 oC by 2050, and 1.56 - 5.44^ºC by 2080. This may anticipate greater instability in agricultural production (Aggarwal, 2008). Beside this, climate change also affects the dynamics and frequency of extreme events like tropical cyclones, associated storm surges, and rainfall events. Low lying regions are more vulnerable to climate change as increase in temperature melt down the glaciers causing floods, submergence, and degradation of these regions. Therefore, there is a need for a ‘wake up call’ at this stage to aware farmers about the climate change, extreme weather events like hailstorm, heat and cold waves, drought, flash and river floods and landslides, and its affect on crop and agriculture, and strategies to overcome it.

Introduction

Greenhouse gases (GHGs) are the atmospheric trace gases which absorb and emit infra-red radiation and thereby trapping the heat radiated from the earth surface. The commonly known agriculturally important GHGs are carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O). The major anthropogenic sources of CO₂ emission in atmosphere are biosphere, burning of fossil fuels and land use changes in tropical forests. The atmospheric concentration of CO₂ has increased from 280 parts per million by volume (ppmv) in 1750 to 394 ppmv in 2012 and is currently increasing at the rate of 1.9 ppmv year-1 (NOAA, 2012). Atmospheric CH₄ concentration has increased from about 715 to 1826 parts per billion by volume (ppbv) in 2012 over the same period and is increasing at the rate of 7 ppbv year-1 (IPCC, 2007; EPA, 2013). Similarly, the atmospheric concentration of N₂O has increased from about 270 ppbv in 1750 to 325 ppbv and is increasing at the rate of 0.8 ppbv year-1 (IPCC, 2007; EPA, 2013).

Global warming is the most prominent environmental issue across the world. It is caused by the increased concentration of greenhouse gases (GHGs) in the atmosphere and leads to a phenomenon widely known as ‘greenhouse effect’. Amongst various sources of greenhouse effect, agriculture is considered a major contributor primarily through the emission of greenhouse gases such as methane, nitrous oxide and carbon dioxide.

Introduction

In many developing countries including India, agricultural sector is of vital importance to the economy and welfare of the inhabitants. Agriculture contributes to 14% of the Indian GDP and supports the livelihood of two-thirds of the population. Despite tremendous technological developments, vagaries of weather continue to plague the agriculture production. Any shortfall in agricultural production will have its cascading effect on the economy of the country. In recent times, climate change and variability are confounding the troubles already faced by Indian agriculture and the farming community. Loss in crop production and farm income due to unexpected weather hazards is beyond the carrying capacity of resource poor farmers of the country. With the growing commercialization of agriculture, the magnitude of crop loss due to unfavourable weather hazards is increasing leading to suicides of farmers. The State and National governments on their part are coming to rescue of farming community by implementing various relief measures like reduction or suspension of land revenue taxes, loan waiving, relief from calamity relief fund etc. Though these measures are helpful, farmers cannot expect them as a right and they put lot of burden on the country’s exchequer.

In recent past, extreme weather events are causing great concern in different sectors contributing to Indian economy. India Meteorological Department is doing yeomen’s service by providing advance information including monitoring of the extreme events longs with proper advisories to the farming community by using state of art instruments & technology through efficient delivering mechanism of the information and ultimately help the farmers from incurring great loss. In many cases, the most severe impacts are felt when several extreme events occur together. The major extreme weather events related to agriculture are Tropical cyclones, floods, heavy rain and landslides, cold waves, fog, snow storms, Heat waves, Hailstorms, thunderstorms and dust storms, drought.

The UN designation of 2013 as the International Year of Water Cooperation aptly demonstrates growing gap between water supply and demand. These symptoms, which are already visible in a few regions around India, are soon to assume a national proportion and may become permanent feature of the water sector in the country, unless suitable policies are adopted quickly to manage water demand and supply at different levels. Water demand is growing fast due to a rapid population growth and economic activity, but water supply is not growing at the same rate because of serious ûnancial and physical limits for supply augmentation. Water resources developed at present amount to about 680 km³, which constitutes 61% of the utilizable potential of 1122 km³. However, it is difficult to add supply beyond this level due to heavy costs, environmental concerns and interstate water conûicts. In contrast, the total demand for water is projected to reach 784–843 km3 by 2025 and 973–1180 km³ by 2050 (Ministry of Water Resources, 2000). Recent research studies predict that, if the demand– supply gap continues to increase, nine basins that have over four-ûfths of the total water use in India will face physical water scarcity by 2050 (see Amarasinghe et al., 2007). For a heavily populated, monsoon-dependent and rural-based country, such as India, water scarcity of this magnitude will not only lead to serious water conûicts among sectors and regions, but also have a devastating effect on the food and livelihood fronts.

Recent increase in extreme climate events threatens disruptive impacts on both animal and agriculture (Battisti and Naylor, 2009). Climate change is a global phenomenon, but its negative impacts are more severely felt by the poor people in developing countries. Moreover, rural poor communities rely greatly for their survival on animal and agriculture which belong to the most climate-sensitive economic sectors. Climate change is expected to intensify existing problems and create new combinations of risks. The incidences of droughts, snow-storms and blizzard like events have increased rapidly. The situation has further worsened due to factors such as widespread poverty, over dependence on rain-fed agriculture, inequitable land distribution, limited access to capital and technology, inadequate infrastructure, long term weather forecasts and inadequate research and extension. The impact of climate change is expected to heighten the vulnerability of animal systems and reinforce existing factors that are affecting animal production systems in many parts of the world.

Increasing evidence over the past few decades indicate that significant changes in climate are taking place worldwide as a result of enhanced human activities. The inventions that were discovered during last few centuries, more so in the last century has altered the concentration of atmospheric constituents that lead to global warming. The major cause to climate change has been ascribed to the increased levels of greenhouse gases like carbon dioxide (CO₂), methane (CH₄), nitrous oxides (NO₂), chlorofluorocarbons (CFCs) beyond their natural levels due to the uncontrolled activities such as burning of fossil fuels, increased use of refrigerants, and enhanced agricultural related practices. The temperature increase is widespread over the globe and is greater at higher northern latitudes. Land regions have warmed faster than the oceans. January 2000 to December 2009 was the warmest decade on recordreported by NASA. These activities accelerated the processes of climate change and increased the average global temperatures by about 0.8°C (1.5°F) since 1880 (NASA,2010). Global average sea level has risen since 1961 at an average rate of 1.8 [1.3 to 2.3] mm/yr and since 1993 at 3.1 [2.4 to 3.8] mm/yr, with contributions from thermal expansion, melting glaciers and ice caps, and the polar ice sheets. Satellite data since 1978 show that annual average Arctic sea ice extent has shrunk by 2.7 % [2.1 to 3.3%] per decade, with larger decreases in summer of 7.4% [5.0 to 9.8%] per decade. Mountain glaciers and snow cover on average have declined in both hemispheres. It has also induced increased climatic variability and occurrence of extreme weather events in many parts of the world.

Global warming is the biggest long term threat to life on earth. Rise in temperature may drive thousands of species to extinction, trigger more frequent floods and droughts and sink low lying islands and coastal areas by rising sea levels. It is the result of rising atmospheric content of CO₂ mainly owing to burning of hydrocarbons or fossil fuels like as petrol and diesel. Destruction of forests and their degradation too contribute to rise in carbon dioxide levels. The IPCC (2006) projected the rate of warming for the 21st century to be between 0.8 and 4.4^ºC at various stabilized CO₂ levels in atmosphere and it is most likely to be 3°C by the end of this century. It could cost global economy almost $7 trillion by 2050, is equivalent to a 20% fall in growth if no action is taken on greenhouse gas emissions. If action is taken, it will cost only $350 billion due to climate change already taken place, just 1% of the global GDP. The winter 2007 was the warmest and recorded 0.85^ºC above average of 12oC and the previous highest was 0.71^ºC, which occurred in 2002 in Northern Hemisphere. The entire Europe Union recorded the warm winter, having more than 2^ºC above average. New York experienced the highest temperature of 21.7^ºC on a day in January, 2007 and the second highest was recorded as 17.2^ºC in 1950. The year 2007 was the warmest winter in the NHS. However, floods and excess rains were also noticed due to hurricanes and tropical storms worldwide in 2007. The year 2010 was the warmest year in India, followed by 2009. It was the second warmest year globally after 1998. It was also one of the wettest years globally in recent years and it was a landmark in annals of climatology.

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.

The annual milk production in Tamil Nadu during 2009-10 from crossbred cows, non-descript cows and buffaloes were 42.28,7.89 and 7.61 lakh tones, respectively. Tamil Nadu had 59.83 lakhs crossbred female cows in the year 2007 as against 41.47 lakhs in 2003 with an annual growth rate of 9.59 per cent (Anon, 2010). With the increasing crossbred cattle population and average annual production, better management of the high producers becomes a necessity. Production and health of animals depend mostly on environment in which they live. A satisfactory environment for any farm livestock is the one that ensures not only optimal productivity but also meets the health and behavioral needs of the animals. A satisfactory environment is the one that satisfies the following four criteria: thermal comfort, physical comfort, disease control and behavioral satisfaction. The most important environmental interventions done in recent days are those that have been done in housing and other attempts to ameliorate the thermal environment. The effort of the body to maintain a stable internal environment to challenges from widely variable environments was first described by Claude Bernard (1878) and later referred to as homeostasis (Cannon, 1932). An environment in which stressors are minimized would likely be favorable for efficient production of products derived from domestic farm animals and for helping ensure the well-being of those species.

Heat or thermal stress occurs when it becomes increasingly difficult for dairy cow to maintain a normal core body temperature of 101.5 to 102.8° F (rectal temp.). The thermo neutral or comfort zone (TNZ) for cow is at an environmental temperature of 41 to 77° F. Within the TNZ, heat production from normal metabolic functions is about equal to the heat loss from the body and maintaining a normal body temperature is relatively easy. Extent of heat stress can be measured by the Temperature Humidity Index (THI). A THI level above 75 is considered stressful for dairy animals. Two sources of heat impact the cow as the environmental temperature and the heat produced internally from basal nutrient metabolism. Heat produced from nutrient metabolism is a lesser factor than environmental heat sources. However, as milk production and feed intake increase, more heat from nutrient metabolism is produced aggravating any heat stress being incurred from environmental sources. Therefore, higher milk producing cow will be more affected by heat stress than low milk producing or dry cow. 

The camel is an important animal component of the fragile desert eco-system. With its unique bio-physiological characteristics, the camel has become an icon of adaptation to challenging ways of living in arid and semi-arid regions. The proverbial Ship of Desert earned its epithet on account of its indispensability as a mode of transportation and draught power in desert but the utilities are many and are subject to continuous social and economic changes. The camel has played a significant role in civil law and order, defence and battles from the ancient times till date. The world famous Ganga-Risala of erstwhile Bikaner State was accepted as Imperial Service Troup and participated in World War I and II.

The Fourth Assessment Report of the United Nations Intergovernmental Panel on Climate Change (IPCC), after analysis of more than 6000 peer reviewed publications has assessed potential effects of changing climate on various spheres of life (Solomon et al., 2007). Under different scenarios, the estimated temperature rise of 1.1 to 6.4 °C in the global surface temperature is predicted at the end of 21st century (period 2090-2099 relative to 1980-1999). Global average sea level in the last interglacial period (about 125,000 years ago) was likely 4 to 6 m higher than during the 20th century, mainly due to the melting of ice in the polar regions. It has been detected in changes of surface and atmospheric temperatures in the upper several hundred metres of the ocean, and in contributions to sea level rise (Solomon et al., 2007). The change in climate is concurrent with the changes in global levels of carbondioxide, methane, oxides of nitrogen etc, loss of biodiversity, natural habitat and other natural resources. The IPCC report also estimates a confidence level of 90% that there will be more frequent warm spells, heat waves and heavy rainfall and a confidence level of 66% that there will be an increase in drought, tropical cyclones and extreme high tides. The magnitude of the events will vary depending on the geographic zones of the World (Solomon et al., 2007).

Yak (Poephagus grunniens)is the most remarkable and multipurpose domestic animal living at high altitudes of the Himalayas. Features common to the environment in which yak live are extreme cold, mountainous terrain, high altitudes with reduced oxygen in the air, high solar radiation and short growing seasons for herbageanda variable assortment of herbage, sparse insome areas. Generally, the yak habitat ranges from 3000-6000 m abovemean sea level (msl), where the alpine pastures are found and there is no absolutely frost-free period during any part of the year. Wilted herbage provides some sustenance for the yak at other times of year, but not insufficient quantity for their requirements (Fig. 9.1). Many of thecharacteristics of the yak can be regarded as adaptations to these conditions, in which cattle of other species have difficulty in surviving (Wiener et al., 2003).The yaks are considered as the life line of the highlanders in remote terrain because yak is the only sustainable livelihood due to non-availability of arable land for major agriculture. Yak husbandry is one of the important and indispensable aspects of the Indianstates, namely, Arunachal Pradesh, Himachal Pradesh, Jammu and Kashmir, Sikkim and Garhwal hills of Uttarakhand where other livestock species can hardly live but yaks can survive, reproduce and produce milk, meat, wool and other by-products.

Mammals are homeothermic, meaning that they have the ability to control their body temperature within a narrow range in an environment whose temperature may change over a wide range.

India is experiencing a phenomenal spurt in the growth of livestock and poultry sectors through various timely and quality measures scientifically over a few decades. Milk production rose by a large leap from about 17.0 million tones in 1950 to about nearly 100 million tones in 2005 standing first in the world for maximum quantum of milk production. From about a ‘naught’ during 1950, the commercial layers have increased to 220 millions in 2005 producing 4500 crores of eggs every yearranking 5th in the world. The meat production is absolutely fascinating with 20 million birds in 1960 to about 2100 million in 2005 (Table 10.1).

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)

The greenhouse effect is thought to be due to the absorption of solar infrared (IR) radiation by gases and the earth’s surfaces, which, as a result, is heated and then reemit IR radiation at low frequency with a high absorptive power. In fact greenhouse gases in the atmosphere are essential for maintaining life on earth, as without them the planet would be permanently frozen because all of the incoming heat from the sun would be radiated back into space by the earth’s surface (Moss, 1993). The threshold concentration of these gases at which their greenhouse effect would be minimized is not known, but it is accepted that their concentrations in the atmosphere should not be allowed to continue to rise. In recent years, there has been an increase in public concern over environmental damage originating from animal feeding operations.

The arid and semi-arid regions of India are drought prone and the availability vegetation of these regions is more acute during summer when the quality of the pastures becomes vulnerable. Small ruminants in the semi-arid regions need to adopt special physiological function to maintain thermal equilibrium. The reproductive efficiency of different breeds of sheep inhabiting in the semi-arid regions of India is relatively low (Arora and Garg, 1998).The nature of nutritional resources and management problems differs with climate, soil and vegetation, the physical process which governs the animals reproductive performance are the same; the female must reach puberty, show behavioral estrus and shed one or more ova which have then to be fertilized. Dietary nutrition promotes the programming and expression of the metabolic pathways that enable animals to achieve their genetic potential for reproduction. Nutrition has an important impact on the reproductive performance in sheep, but the magnitude of the effect on reproduction may vary with the season (White et al., 1983). Sheep are more prone to neglect compared to cattle and often suffer from lack of feed and fodder. The animals during the grazing are exposed to combined stress (Sejian et al., 2010 ab, and 2011) .This leads to decrease in body weight and loss of reproductive functions. Concurrently, Rhind and Mc Neilly (1986) showed that ewes with low body fat reserves had fewer large ovarian follicles and therefore the potential for subsequent maturation and ovulation declined. 

The demand for agricultural and livestock products is rising and the challenge to feed 8 billion people in 2020 is considerably enormous. Further, it is also hard to imagine meeting 2050-projected demand by raising twice as many poultry, 78% more small ruminants, 58% more cattle and 37% more pigs, without further damaging natural resources (Rivera and Lopez, 2012). Hence, sustainable development based on balance of ecology, economics, norms and values are to be considered at various levels of the scale: between food and farming systems, regions, nations and continents (Zipp, 2003). The food systems encompass activities related to the production, processing, distribution, preparation and consumption of food; and the outcomes of these activities contributing to food security (Fig. 14.1).The interactions between and within bio-geo-physical and human environments influence both the activities and the outcomes.

In India, being predominantly an agricultural country, livestock is emerging as a driving force in the growth of agricultural sector. Contribution of livestock to agriculture GDP has been rising steadily during the last three decades from 13.88% in 1980-81 to 27.28% in 2010-11 (BAHS 2012). About 70% population of the Country is engaged in agriculture and more than 50% of people below poverty line are associated with livestock production. India is blessed with a rich genetic resource of bovines, with an estimated number of 304.76 million (Livestock Census, 2007), which is 19% of the world. India continues to be the highest milk producing country in the world with an estimated production of 121.8 million tonnes during 2010-11 of which more than 53% is contributed by buffaloes (105.34 millions). Similarly, India ranks first in buffalo, second in cattle and goat, third in sheep, fourth in duck, fifth in chicken and sixth in camel population of the world. India is the third largest egg producer in the world (BAHS 2012). India posses a large treasure of domestic animal biodiversity with 37 breeds of cattle, 13 breeds of buffalo, 23 breeds of goat, 39 breeds of sheep, 6 breeds of horse/pony, 8 breeds of camel, 2 breeds of pig and 15 breeds of chicken registered under National Bureau of Animal Genetic Resources, Karnal.

Livestock farming is an integral part of crop farming and contributes substantially to household nutritional security and poverty alleviation through increased household income. Indian agriculture is an economic symbiosis of crop and livestock production with cattle as the foundation. Dairy animals produce milk by converting the crop residues and by products from crops which otherwise would be wasted. Dairy sector contributes by way of cash income, drought power and manure. Livestock provides for human needs by way of food, fibre, fuel, fertilizer, skin and traction. India has the largest livestock populations in the world. It has 57 per cent of the world’s buffalo population and 16 per cent of the cattle population. It ranks first in respect of cattle and buffalo population, third in sheep and second in goat population in the world. 70 per cent of the livestock are owned by 67 per cent of small and marginal farmers. 76 per cent of the milk is produced by weaker sections of society. Out of total livestock in the country, 37.28 per cent are cattle, 21.29 per cent are buffaloes, 12.71 per cent are sheep, 2640 per cent are goats and only 2.01 per cent are pigs. All other animals are less than 0.37 per cent of the total livestock. The species-wise breakup of livestock population in India (Table 16.1)

“Terra”per se is an extraordinarily complex, messy geophysical system with dozens of variables, most of which change in response to one another. The basic proposition behind the science of climate change is also rooted in the floral and faunal cohabiting with the Homo sapiens. Livestock and related fodder cultivation and the green waste generated in a farming enterprise are of extreme significance when we ponder over the climate change. Confusion and complacency reigns the thinking process and planning process related to climate change. Confusion in the sense, that risk communication in this regard is so placid. Complacency, we say due to the lackadaisical attitude of our policy makers. To make it very plain, fodder production sector as well as farm sector will suffer the most in Kerala for want of scientific thinking, planning and execution.