eChapters

9.1 Introduction

After knowing when to irrigate and how much to irrigate, next important thing is how to irrigate the crop field. Methods of irrigation plays a very crucial role in deciding how to irrigate the crop fields since all the crops do not require same methods of irrigation. Depending on the sources of water available for irrigation, type of crop to be irrigated, quantity and quality of water to be applied and other economic considerations, methods of irrigation will vary. Irrigation water may be applied to the crops by flooding it on the field surfaces as surface irrigation, by applying it beneath the soil surface as sub irrigation, by spraying it under pressure as sprinkler or overhead irrigation or by applying it in drops around the root zone of the crop as trickle irrigation. The commonly used methods of irrigation are described in schematic diagram as follows

10.1 Application Efficiency and Irrigation Uniformity

All irrigation systems have some non-uniformity. This non-uniformity influences yields and irrigation efficiency especially application efficiency. If the net amount of water applied during irrigation is the same as that required to fill the soil water deficit, then because the distribution of water is never perfect, half of the field will receive too much water while the other half will receive too less water. In such a context, a farmer will try to apply more irrigation water to his field so that a larger fraction of the field has an adequate amount. This will tend to have higher percolation and runoff and thereby declining the application efficiency. An alternative to adding extra water is to improve the uniformity of water application. A major advantage when the uniformity is improved is that the amount of deficit in the area under irrigation is reduced and the potential for water logging and salinization is also reduced.

11.1 Performance of Farm Irrigation Systems

The performance of farm irrigation systems is determined by the efficiency with which water is delivered to the field and utilized to the fullest amount possible with minimum losses due to seepage and percolation, runoff, evaporation and other operational losses. The efficiency of the irrigation system will increase if the conveyance losses, application losses and other losses are reduced to a great extent.

11.1.1 Overall Efficiency

The overall efficiency of a farm irrigation system is defined as the percent of water applied to the farm that is used for irrigation on the farm. Irrigation efficiency otherwise called as overall system efficiency is defined.

1.1 Introduction

Increased emission of greenhouse gases results in climate change which becomes one of the most prominent environmental issues to the world today. Carbon dioxide (CO2) is the major greenhouse gas whereas nitrous oxide (N2O) and methane (CH4) are other substantial contributors to climate change (IPCC, 2014, Tongwane et al., 2016). However, these gases are emitted in minimal quantities in comparison to carbon dioxide but impart more global warming effect by absorbing more infrared radiations (Oertel et al., 2016). The warming potential of one kg of CH4 is 23 times more than one kg of CO2 while  in the case of N2O, it was nearly 300 times more than CO2 (Ramaswamy et al., 2001, Bharti et al., 2019; Biswas et al., 2010). Around one-third of methane and two –thirds of nitrous oxide come from soil (Prather et al., 1995, Tubiello et al., 2015, Smith, 2016).

3.1 Introduction

A Massive increase in population, urbanization and industrialization have led to an increase in the quantity and composition of waste. The waste is increasing day by day and is estimated to reach up to 2.2 billion tonnes by 2025, according to the reports by World Bank. It becomes a necessity for every nation to fore look upon the waste management system for their respective countries. From the collection, segregation, transportation, disposal all have become an important criterion to deal with. Among the available disposal options; the easiest and environment friendly is “Recycling”. 

4.1. Introduction

Presently, in the world, there are 195 countries according to the United Nations, and the number would even go up to 247 if we consider the disputed territories like Isle of Man, Hong Kong, etc. (United Nations, 2016) (Kershner, 2020). But the majority of the countries are still struggling to provide basic life-supporting amenities like nutrition, shelter, and employment. Conjointly, termed as emerging and developing countries such as India, Vietnam, Venezuela, Utopia, etc. (Ahmed and Shimada, 2019). Most of the developing countries are situated mainly in the continent of Africa, Asia and South America. They have got independence for the European countries like England, France, Portugal and Spain in the mid and late 20th century. 

6.1 Introduction

Urbanization is now a global phenomenon, but in developing countries the implications are more pronounced. Natural growth of population, reclassifications of habitation and migration trends are important in urban population in India. The population of India, which accounts for 27 per cent of the total population, was 285 million according to 2001 census. International experience shows that the pace of urban development accelerates when a country’s urban population crosses close to 25 percent of the total population (like in India).(Kumar and Chakrabarti, 2010). 

10.1 Introduction

The consistent process of rapid urbanization and expeditious developmental activities have severely impacted the environmental components and thereby the quality of life. With limited natural resources, individuals and societies have to learn to bring in attitudinal changes in order to accomplish environment sustainability (UNESCO). From the Book “Our Common Future” (Brundtland Report), the concept of Sustainable Development can be understood as the “development that meets the needs of the present, but does not threaten the ability of future generations to meet their own needs”. 

Geographic location of India is in Northern hemisphers and located between 80 4' & 370 6' N latitude and 640 7' & 970 25' E longitude. Extent of area is 329 M Ha or 329 x 104 Sq.Km or 3.29 MSq.Km. The physiography of India can be broadly grouped into triangular plateau, mountains, Indo-gangetic plains and islands. India is divided into twenty agro ecological regions and sixty five agro ecological sub regions as per NBSS and LUP. Agro ecological regions( AER) is referred to identification and demarcation of land units having comparable landform, soils, bioclimatic conditions and the length of growing period (LGP).

India is an agriculture based country which is one of the few developing countries in the world. It successfully achieved Green Revolution during the late 1960s (1967-68). At present, agriculture is a principal means of livelihood for over 58.4 per cent of Indiaís population directly or indirectly (Anonymous, 2011). It is worthwhile to mention that although agriculture continued to be the mainstay of the Indian economy previously (Anonymous, 2010b) yet now its share in the Indian economy is declining year after year (Anonymous 2013d). After Independence, agricultureís sector contribution to GDP swings between 50-60 per cent. Even in 1950-51, it was 55.1 per cent, but fell to mere 17-18 per cent in 2008-09 (Mahajan and Gupta, 2009).

Agricultural production has made rapid strides in the past four to five decades and has enabled India to achieve self-sufficiency in food grain production. This was only through ìGreen Revolutionî which ushered during 1967-68 onwards, when use of old agricultural practices were mostly done away with. Neglect of old or indigenous agricultural practices such as use of organic manures (farm yard manure - FYM, compost, green manure), cultural control methods like sanitation, tillage/removal of weeds, adjusting sowing/harvesting time crop rotation, trap crops, water and fertilizer management and host plant resistance, and use of plant based insecticides like neem or nim (Azadirachta indica), drek (Azadirachta indica), nirgudhi or bana (Vitex negundo) vis-a-vis biological control measures, has resulted in outbreak of ill-effects in human beings and animals through contaminated food stuffs (Gupta, 2006a).

In modern times, soil tillage has emerged as an integral part of a crop system. Soil tillage or soil surface management has been found important in alleviating soil related constraints encountered in crop production. An important effect of soil tillage on crop productivity is through its influence on soil processes, soil Soil Tillage 39 properties and crop growth. At the same time, soil tillage has its impact on the environment e.g. soil degradation, water quality, emission of green house gases from soil related processes etc.

Water is precious, but it is a finite natural resource. Although it accounts for about three-fourth of the earthís surface yet very small fraction of it i.e., only 2.7 per cent of the global water is available as fresh water. Around 2.8 billion people live in areas of high water scarcity (Anonymous, 2014d). Out of the total amount of the fresh available water merely 30 per cent is withdrawn to meet the water requirements of the human and livestock population while the remaining 70 per cent is required to produce food crops that fuel human activities.

Bio-fertilizers, as the name indicates, are the fertilizers of biological origin (Gupta, 2012). In strict sense, real bio-fertilizers are green manures and organics - materials of biological origin which are added to supply plant nutrients present in them. However, in restricted scope, the term ìbio-fertilizersî or ìmicrobial inoculantsî are preparations of living organisms in alone or in combination, which may help in increasing crop productivity by way of fixing atmospheric Use of Bio-Fertilizers in Sustainable Agriculture 175 nitrogen in soils, solubilizing of insoluble plant nutrients, stimulating plant growth or decomposing of plant residues. 

Ever increasing use of chemical fertilizers without an adequate organics has deteriorated the fertility and productivity of soil and also aggravated multi-nutrient deficiencies in soil and plant system (Gupta and Singh, 2006). Further, change in the cropping pattern, intensive cultivation and indiscriminate use of pesticides with an objective to obtain more and more crop yield, has not only made agriculture a profitable commercial venture but has also brought in several problems of pests and diseases, and ecological crises. As the nitrogenous fertilizers are soluble and as such they may leach down into ground water as for example presence of nitrate in underground waters of some parts of UP, Haryana, Punjab, Gujarat, has become a potent source of blue baby disease (Gupta, 2005).

Agriculture is the main stay of Indian economy as more than 60 per cent of the people of India are dependent upon this evocation and allied disciplines for their livelihood. Even today, at the dawn of 21st century, the Indian agriculture has continued to be the backbone of our National economy, representing countryís about one seventh of Gross Domestic Product (GDP). Thus, farming families consisting both of men and women, boys and girls, known as the pillars of our agriculture constitutes backbone of the Nation. The support and contributors made by the rural women in agriculture, consisting 50-60 per cent of farm work force are, however, not less than those performed by the men, and therefore they become spine of the rural economy.

In spite of the fact that the forests are the wealth of a nation and play a vital role in the economy of the country, not much attention has been paid to their promotion, protection and conservation. The forests of India have been reduced to 19.27 per cent (Gupta and Khajuria, 2000) and/or 23 per cent including 20.55 per cent forest cover and 2.48 tree cover (Sharma, 2005). It is much less than as prescribed in the National Forest Policy (1952), according to which onethird i.e. 33 per cent of the total land area of the country must be under forest.

North Eastern Himalayan Region comprises mostly of seven states viz. Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura (Gill, 2005). This Himalayan Region stands entirely different from the rest of the country not only in language, dress, food habits and festivals but also differs in agricultural practices. Among agricultural practices shifting cultivation locally known as ìJhumî or ìBunî is the most important. According to Ministry of Agriculture, Arunachal Pradesh stands first in the ìJhumî cultivation followed by Assam, Manipur, Meghalaya (Agnihotri, 2003). In Meghalaya, the problem has assumed an epidemic proportion in Gargo hills where tracts of forests are burnt. The farmers of Khasi and Jainta Hills usually practise the ìBunî cultivation.

It is an established fact that there is no further scope for horizontal expansion of area under plough, as the per capita land is decreasing every year due to unabated increase in human population. Hence, the future need of food has to be met through vertical expansion i.e. more intensification of agriculture. Nearly 40 million tonnes of nutrients in the form of chemical fertilizers will have to be utilized to feed upon an estimated population of 1.5 billion by 2050 AD (Sakai, 2001). However, presently the crop productivity especially rice and wheat has stagnated not only in India but in other South Asian countries also (Mahajan and Gupta, 2009). 

Agriculture is the lifeline of India that provides livelihood to about 70 per cent of its population dwelling in about 6 lakh villages. In spite of so many projects, programmes and schemes launched from time to time after independence by Government of India through Ministry of Agriculture and Indian Council of Agricultural Research, State Agricultural Universities and Departments of Agriculture, agricultural food grains production was not realized on ìsustainable basisî. Even ìGreen Revolutionî which came to fore during 1967-68 in the irrigated areas alone, could not sustain the productivity of rice and wheat. Rather, the productivity of these crops has either got declined in many cases and/or in other cases it has stagnated.