eChapters

Introduction

Climate is one of the main determinants of agricultural production. Throughout the world there is significant concern about the effects of climate change and its variability on agricultural production. Researchers and administrators are concerned with the potential damages and benefits that may arise in future from climate change impacts on agriculture, since these will affect domestic and international policies, trading pattern, resource use and food security. The climate change is any change in climate over time that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere in addition to natural climate variability observed over comparable time periods (IPCC, 2007).

Introduction

The current population of our country is about 1.27 billion and the world population is predicted to grow from 6.9 billion in 2010 to 8.3 billion in 2030 and to 9.1 billion in 2050. By 2030, food demand is predicted to increase by 50% (70% by 2050). The main challenge facing the agricultural sector is not so much growing 70% more food in 40 years, but making 70% more food available on the plate (UNDESA, 2014). This rising food demand automatically put burden on the shoulder of formers especially for ASEAN countries such as India where population growth rate is high while resources are limited. India has about 141 million hectares area under cultivation out of its geographical area which 329 million hectares (Raghuwanshi, 2012; Parikh and James, 2012). Consequently, agriculture is, thus, one of the most important factors contributing to the economic growth of India (Kniivila, 2007). The production of the agricultural produce should be up to the mark to maintain this contribution. In order to enhance the crop production, fertilizers are needed because they supply the nutrients to the soil. By adding fertilizers, crop yields can often be doubled or even tripled.

Introduction

The vast majority of climate change impacts and the overall impact of climate change on rice production are likely to be negative. Overwhelming scientific research and evidence have shown that the climate is ongoing. According to the International Food Policy Research Institute (IFPRI) report Climate Change: Impact on Agriculture and Costs of Adaptation forecasts there will be an increase in the net price of rice between 32 and 37% as a result of climate change by 2050. They also show that yield losses in rice could be between 10 and 15%. While there is still ongoing scientific exploration into climate change, IRRI recognizes two universal trends predicted by all climate change models viz., temperatures will increase, resulting in more heat stress and rising sea levels and there will be more frequent and severe climate extremes.

Introduction

Climate change and climate variability have become a reality. Recent climate changes have widespread impacts on human and natural systems including agriculture. According to Inter-Governmental Panel on Climate Change (IPCC, 2007), climate change refers to a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended period (typically decades or longer). For example, it could show up as a change in climate normal (expected average values for temperature and precipitation) for a given place and time of year, from one decade to the next. Climate change may be due to natural internal processes or external forcing, or to persistent anthropogenic changes in the composition of the atmosphere or in land use. In last 130 years (1880-2012), the global averaged combined land and ocean surface temperature has increased by 0.85 [0.65 to 1.06] °C (IPCC, 2014). This increase in temperature is disturbing global climate system as a result we are observing climate change on entire continent. IPCC has projected the temperature increase between 1.1 °C and 6.4 °C by the end of the 21st Century (IPCC, 2007).

Introduction

Ground water (GW) resources in most areas of world are shrinking at an alarming rate and may not meet the ever increasing demands from agriculture and industry in future. Large decreases in GW levels (up to 200 m in some places) have been observed due to over exploitation (Toze, 2006). It accounts for more than 65% irrigation water and 85% of drinking water supplies lies in a critical state. Many areas of the world, already experiencing stress on water availability, which placed severe strains on existing resources with resulting environmental impacts. Half of the population of the developing world suffers from at least one disease caused by insufficient water supply and sanitation.

Introduction

Global food production, already under the credit crunch, must double by 2050 to level off hunger. According to the UN World Food Programme (WFP), this will be possible only if food security is given top priority. The food security has become a complex issue influenced by climate and non-climate induced stressors which operate independently or in combinations are tackled appropriately. This climate induced stress is further augmented by climate change which affects agriculture and food production in complex ways. It affects food production directly through changes in agro-ecological conditions and indirectly by affecting growth and distribution of incomes, and thus demand for agricultural produce. Climate change has emerged as a major challenge in achieving goals of sustainable agriculture. Climate change refers to any change in climate over time, whether due to natural variability or/and as a result of human activity (IPCC, 2007). Agriculture impacts climate change with greenhouse gas emissions, and is at the same time impacted by effects of climate change as well. Amongst elements of climate change, the most important relate to increasing uncertainty in availability of water due to increasing frequency of drought and/or excess water events resulting in uneven water availability over time and space. Drought is a normal, recurring feature of the climate in most parts of the world. Drought is defined as the absence of rainfall or supplemental irrigation for a period of time sufficient to deplete soil moisture and injure plants. According to USDA drought occurs when annual precipitation is 75 percent of normal, or monthly precipitation is 60 per cent of normal. Drought stress results when water loss from the plant exceeds the ability of roots to absorb water and when the plant’s water content is reduced enough to interfere with normal plant processes.

Introduction

“Food insecurity is an enormous challenge at a global scale, with strong implications both for environmental management and for socio-economic development” (Rockstrom, 2003). This is exaggerated by persistent drought and uneven distribution of rainfall resulting in low crop yield. As the results, millions of lives are threatened with starvation caused by food shortages particularly in the arid and semi arid regions where majority of population still rely on rain-fed agriculture to secure food security (Ntsheme, 2005).

The majority of the affected population threatened with starvation resides in the rural areas with little or no income at all. It is projected that large number of population will be without food in coming years. This is exacerbated by slow economic growth and poor performance in the agricultural sector. It is likely that the increment of the food gap will occur in the near future intensifying the shortage of food in the region (Kundlande et al, 2004).

Introduction
Climate change has become an issue of global concern and has a direct large scale impact on land and marine biosphere. The expected and unlikely events like increase in temperature, melting of glaciers and rising of sea level, increase in magnitude  and frequency of drought and floods, cyclones/tsunamis, desertification, heat and cold waves, snow fall are most threatening challenges that are being witnesses in the present era. Rain fall is likely to decline by 5-10 % over southern parts of India where as 10-20% increase likely over the other regions. There is probable decrease in number of rainy days over major parts of the country pointing at likely increase of extreme events of floods or drought. In India, salt affected soils currently estimated to be 6.73 M ha in different agroecological regions and  the area is likely to be almost turn to 20Mha by 2050. Framing breeding strategies to develop climate resilient varieties is necessary to mitigate adverse effects of climate change.

Introduction

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

Introduction

Increasing evidence over the past few decades indicate that significant changes in climate are taking place worldwide and its effects are surreal. Major cause to climate change has been ascribed to the increased levels of greenhouse gases like carbon dioxide (CO₂), methane (CH₄), nitrous oxides (N₂O), chlorofluorocarbons (CFCs) beyond their natural levels due to the uncontrolled human activities such as burning of fossil fuels, increased use of refrigerants, and enhanced agricultural activities. 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 polar ice sheets. The climatic changes are resulting in erratic weather patterns and the impacts are already being manifested in many parts of the world and coastal agricultural systems are nearing crisis point. The IPCC has projected that during the 21st century the global surface temperature is likely to rise a further by 1.1 to 2.9 °C as per their lowest estimation model and by 2.4 to 6.4 °C as per their higher estimation model.

Introduction
 
Food production systems in India are becoming increasingly vulner-able to climate variability and change which are largely characterized by altered frequency timing and magnitude of precipitation and temperature that trigger a series of other devastating events. High rates of snow and glacial melting, frequent floods and droughts, heat waves, hail and increased incidence of pests and diseases are already causing widespread damage and losses to agricultural sector in tropical and sub-tropical countries including India. Overwhelming direct damage to crops and livestock within few minutes can be caused by extreme weather events such as hail, wind­storm, or heavy frost. While occurrence, losses and post disaster management have been discussed extensively for natural calamities such as excess rainfall, drought and flood, little attention has been given to hail storm.

Introduction

Climate change is a big phenomena, it is having a huge impact on agriculture from ancient to present time. It has received wide attention and debate as the public concern has increased about unforeseen change in climate. The impact of climate change on Indian agriculture will be significant since more than 60% of Indian population depends on agriculture for their livelihood with the contribution of agriculture to GDP is approximately 20 percent. In recent decades, human induced changes in climate has the focus of scientific and social attention.

Introduction

Much of the world’s agricultural biodiversity is found in environments marginal for agricultural production. It is in such environments where management of high levels of diversity can become a central part of the livelihood management strategies of farmers and the survival of their communities. Abiotic stress can be termed as the negative impact of environmental factors on the organisms in a specific situation. It is a natural phenomenon that occurs in multiples and interdependent, and its impact varies across the sectors of agriculture. Abiotic stress is the primary cause of crop loss worldwide, reducing average yields for most major crop plants by more than 50%. Drought and salinity are becoming particularly widespread in many regions, and may cause serious salinization of more than 50% of all arable lands by the year 2050 (Wang  2003). Environmental stresses such as erratic and insufficient rainfall, extreme temperatures, salinity, alkalinity, aluminium toxicity, acidity, stoniness and others limit yield and productivity of many cultivated crop plants. Not only are such problems serious today, it seems they are inevitably worsening.

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.

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.

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.

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

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).

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.

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: