eChapters

Field capacity may be defined as the amount of water held in soil after excess water has drained away and the rate of downward movement of water was materially decreased which usually taken place within two to three days after heavy rain or irrigation. In this condition water was moved out of the macropores and air has moved into take its place. 

The soil water plays an important role in the physical, chemical and biological activities taken place in the soil which directly or indirectly affects the crop growth. The water content of the soil can be measured by different methods. These methods are gravimetric method, neutron scattering method and electrical resistance method.

Primary particles tend to adhere under natural condition so as to form secondary unit called aggregates. It is very difficult to determine the diameter of the individual aggregated particle. So the mean weight diameter is calculated as a single value constant, which indicate the wetted average value for a group of aggregates.

Pore space or porosity : Porosity is an index of the relative pore volume in the soil or volume fraction of pores. Its value generally lies in the range of 0.3-0.36 (30-60%). Coarse textured soils tend to be less porus than fine textured soil, though the mean size of individual pores is greater in the former than in the latter. The total porosity, in any case, reveals nothing about the pore size distribution which itself is an important property.

Soil texture is the relative proportion of sand, silt and clay in soil by weight. As per the classification of the inorganic soil particle by the International Society of Soil Science, diameters of the sand, silt and clay particles vary from 2 to 0.02 mm, 0.02 to 0.002 mm and less than 0.002 mm, respectively. There are 3 broad textural groups i.e sand, loam and clay and each broad textural group is subdivided into different textural classes depending upon the proportion of sand, silt and clay.

Aim of the Experiment: The composite soil samples, collected, are air-dried and processed before analysis in the laboratory.

Soil testing identifies various constraints in soil that limit crop production. Fertilizer recommendation and soil management practices to be adopted are based on the soil test report. Soil testing starts with collection of soil samples from the field
and ends with interpretation of soil test results leading to necessary recommendations for increasing crop production.

With the invention of bitcoin in 2008, the world was exposed to a new technology paradigm called blockchain. Blockchain was conceptualized by an unknown person named as Satoshi Nakamoto in 2008. The identity of Satoshi Nakamoto is still not known. Nakamoto proposed the design of blockchain which uses digital signature and timestamps to enable secure and trusted online transaction without the need of any trusted regulatory or third party.

Big Data refers to extremely large, very fast, highly diverse, and complex data that cannot be managed with conventional data management systems, tools or processes. In the perfect world, Big Data may include all kind of data, which can deliver the right information, to right person, in the right quantity, at the right time, to help in making the right decisions.

The term ‘geo’ is a Greek word, it means the earth, and the term ‘spatial’ means parameter/feature measured, mapped or modeled with reference to distance or space. The geospatial technology refers to the technology that measure, model, analyze, map, or predict the features or phenomena that occur on earth and its surface.

The term robot is czech word, first time used by play write Karel Capek, in year 1920, applicable to the forced labour or serfs or slaves. The first commercial, digital and programmable robot, named ‘Unimate’ was built by George Devol in 1954.

One of the major goals in agricultural crop management is to achieve maximum yield with minimum investment while maintaining a good quality of the crop produce. Crop infestation due to insects, diseases, and weeds are some of the major factors responsible for loss in crop yield. Further, an efficient Precision Agriculture Crop Management System is one, which is capable of precisely detecting the crop yield indicators (or crop health parameters) at an early stage and can predict the yield at any point of time of the crop cycle.

Sending a message from one place to another place, which are physically separated from each other, is called Communication. The Communication Engineering or Communication Technology deals with the design and development of engineering systems to transmit information from its source, and at the same time, to receive the same information at a remote destination with reliability, accuracy and quality.

The human civilization and environmental eco-system are the two most important components of real world. The technology intervention to safeguard human civilization and the environment has always been the foremost priority of scientific and engineering community through their innovative expeditions.

Internet of Things (IoT) is networking of physical objects, devices, machines, systems etc to interconnect each other for exchanging data through standard internet protocols. The IoT is also termed as Machine-to-Machine (M-to-M) communication. The term ‘Things’ in IoT includes objects embedded with sensors, actuators, mobile phones, routers, hubs, computers, wearable’s and smart devices etc.

Artificial Intelligence (AI) is technology which can store, retrieve, manipulate, manufacture, transmit or receive, analyze any digital information and can apply machine vision for increasing efficiency and workability of the system. The AI permits systematically scope of ‘3S’ i.e. Safety, Security and Surveillance, which is also known as manmade intelligence. In fact, it needs more reliable and accurate data or information for processing and correction for predicting performance of any system and devices.

Sensor is a physical device used to detect manifestations or variations in a process value and collect data in real time assessment mode for measuring and predicting system/device performance and finally analyzing it to attain a specific task or application. Sensor technology is now-a-days used for interdisciplinary applications for data collection, system analysis and monitoring.

The term digital is derived from the word digit or digitus, a Latin word for finger, as fingers are often used for discrete counting. A variable is discrete when it is countable in a finite time and its instantaneous value at any timing/ instant belongs to a set of finite values.

A disaster is any event natural or manmade which creates an intense negative impact on people goods and services and or the environment and exceeds the affected community internal capability to respond prompting the need to seek outside assistance. In other words a disaster is a serious disturbance of a community or society interfere human resources losses and impacts on economically and environmentally or disaster means simply an event has unfortunate consequences on only on human but also on whole environment. Disaster can be two types’ Natural disaster and manmade disaster.

Environmental Ethics is a conceptual term which consist various aspects of environmental fundaments, Enviromental ethics is responsible to protect and sustain the resources and ecological system.

For the protection of all the factors of environment, laws were formed and amended from time to time as per the requirement. There are many acts according to the main factors and separate laws, for the enforcement. Also, the are some control acts, which can be implemented by states for the local environmental problems.

Sustainable Development A social cause is a problem that influences a considerable number of individuals within a society. There are many environmental issues the India like pollution, waste management sustainable development, rain water harvesting etc.

Solid wastes are all the wastes arising from human and animal activities, that are normally solid and that are discarded as useless or unwanted materials. It consists of the highly heterogeneous mass of discarded materials from the urban community as well as the more homogenous accumulation of agricultural, industrial and mining waste.

Pollution: Environmental pollution in general, may be described as the contamination of the environment with harmful wastes arising mainly from human activities. These activities release certain materials which produce pollution in the atmosphere water and soil. In simple words, environmental pollution may be defined as direct or indirect changes as a result of human activities, which adversely influence the biological and non-biological equilibrium of the environment.

The term biodiversity is used by Walter and Roses in 1985. Biodiversity means the existence of a large number of different kinds of animals and plants which make a balanced environment. According to “Convocation on biological diversity (1992)”-Biodiversity is present in terrestrial, ocean and aquatic ecosystem. This diversity present in between same species, different species and in different ecosystem.

Environment: Environment means “surrounding”. First definition of environment was given by “Ernst Haeckel”. According to this - The relation between all organic and inorganic atmosphere of any animal is called environment.

Natural resources are the resources present naturally in the environment. These resources are used by human being for their survival. Minerals, building stones, forests, and various energy resources are known as natural resources. Natural resources have been extracted and utilized since ancient times but as the population increased, the demand of natural resources are increasing day by day.

A pH meter is very commonly used for the measurement of the reaction of a solution or a medium. The pH determination with the help of a pH meter is based on the measurement of the electromotive force (e.m.f) of a pH cell consisting of an electrode sensitive to W ions and a reference electrode.

The quality of irrigation water is a crucial factor for long-term soil productivity. Poor quality water if used for a long time can make the soil less productive or even barren, depending on the amount and type of constituents present in it and the texture of the soil in question. Low or marginally saline waters sometimes appear to stimulate crop growth because of the higher amounts of nutrient ions present.

Accumulation of nutrient elements in plant tissues indicates the accessibility of the concerned elements from the soil to the plant. Although different plant species and even different varieties of the same species may vary in their nutrient requirements, composition of a part or of the whole plant may well be adopted as a guideline to support the soil-test results for factual assessment of soil’s nutrient supplying power.

Soil sampling is the first step of soil analysis. As very small fraction of the huge soil mass is used for analysis, it becomes extremely important to get a true representative soil sample of the field.

A. CEREALS

1. Rice (Oryza sativa)

RD 60:20:20 kg/acre NPK

(Recommended by TNAU)

While fertilizer injectors that mixes fertilizer solutions with the irrigation water flow in the micro irrigation systems, a scientifically prepared fertigation schedule is the software that farmers need to implement a successful fertigation plan.

Though water soluble fertilizers are a special grade of fertilizers manufactured for fertigation per se; I have been assisting farmers to do fertigation with conventional fertilizers, those are familiar to them; like Urea for N, white muriate of potash (MOP) for K. Only in the case of P source they need to acquire water soluble special fertilizers like Monoammonium Phosphate (MAP) or Phosphoric acid. Historically, fertigation by our small holder farmer began in India just by fertigating Urea alone. And applying P and K as direct dry application to the soil with Single Super Phosphate (SSP) or pink MOP, both are not water soluble. Gradually, when farmers realised that fertigation is giving them more yield of the crop and income they warmed up to the idea of full fertigation and demand for water soluble fertilizers like MAP, White Potash, SOP etc. grew.

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”. 

Introduction

With ever-increasing population growth, waste management has become a major challenge threatening environmental sustainability. The total solid waste generation was recorded to be 1.3 billion tonnes per year by the world’s cities in 2012, with an ecological footprint of 1.2 kilograms per person/day. With the intensity with which the population growth is happening coupled with urbanization, predictions are made that by the end of the year 2025, 2.2 billion tonnes of municipal waste will be generated (The World Bank, 2018). 

8. Introduction

The idea of sustainable development stands on the concept of maintaining the best possible environment within the availability of minimal resources and for the convenience of the society. Now-a-day the term “sustainability” gained a lot of attention due to challenges and problems faced in tackling the current situation of global pollution. One of the vital areas of research needs to be addressed in concern with sustainable development is the new innovations to enhance sustainability (Silvestre and Silva, 2014). 

7.1. Developing Sector in Scientific and Technological Approach of Waste Management

From the very past, many traditional practices have been put into use for waste management like landfilling, composting, and recycling, which are practiced even today. However, the boundless upsurging waste compels the modern world to modify the traditional methods or to introduce innovative techniques with the grace of technology

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). 

Definitions: Before starting the chapter, it is better to understand the basic definitions of the terms commonly used in this chapter.

Waste: Waste is any material or object which is discarded after its primary use by its holder. A holder means the person who produces and keeps the waste. 

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. 

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”. 

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).

1.1. Background Introduction

We live in a world with “throw-away” societies that are involved in a pattern of consuming packaged products that don’t even last past a single use or even a year and discarding the waste. This lifestyle generating waste is negatively impacting public health, environment and imposing socio-economic problems on us. The waste is continuously consuming our land, resources, and energy for storage, management, treatment, and disposal. Solid waste was an urban issue initially but has reached every corner nowadays. 

11.1 INTRODUCTION

The heavy metals which, by definition, are elements having a density greater than five in their elemental form, comprise some 38 elements. However, the term usually, and here, refers to twelve metals that are used and discharged by industry, i.e. Cd, Cr, Co, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sn, Zn. Most of the present discussion will centre on those metals that may represent potential hazards to plants or animals; these are Cd, Cu, Hg, Ni, Pb, and Zn.

The heavy metals are widely distributed in the environment, in soils, in plants and animals and in most of their tissues. The concentrations of individual metals in living tissue are ordinarily very low and must be maintained within narrow limits to permit the optimum biological performance of most organisms. Some heavy metals are essential in trace amounts, namely Co, Cu, Fe, Mn, Mo, Zn for plants and, in addition, Cr, Ni, Sn for animals; Cd, Hg, and Pb, have not been shown to be essential for either plants or animals. Deficiencies of the essential metals have been frequently reported and substantial benefits have arisen from correcting these by addition to the soil and subsequent transfer from soil to plant is for most increasing concern about the entry into soil of some heavy metals and the possible adverse effects that they might have on plants and animals and, in turn, on human health. The main sources of these heavy metals are: (i) urban industrial aerosols, created by combustion of fuels, metal ore refining and other industrial processes; (ii) liquid and solid wastes from animals and man; (iii) mining wastes; or (iv) industrial and agricultural chemicals. Although in some circumstances there are direct atmospheric inputs to plants, addition to the soil and subsequent transfer from soil to plant is for most heavy metals the major route of entry into the living tissues of plants, animals, and man. The fate of heavy metals added to soils, including their mobility and reactions in the soil and their subsequent uptake and distribution in plants, is therefore of critical importance in relation to man’s health.

10.1 INTRODUCTION

The fate of plant nutrients in fertilizers added to soils is to be: (1) taken up by crops; (2) retained by the soil; (3) removed in solution in drainage water; (4) lost as a gas; or (5) removed by erosion. These five processes are discussed in this chapter. The purpose of using fertilizers is to increase crop growth and they fail in this unless they are taken up by plants. Table 10.1 gives FAO (1972) data which show that large fertilizer use is restricted to the developed countries which use 65 times the amount used per hectare in developing countries. Within the group of ‘developed’ countries most of North-West Europe uses much fertilizer; outside of Europe large use per hectare is confined to a few countries such as Japan and USA. It is in the developed countries where much fertilizer is applied that efficient uptake of plant nutrients is already important to national economies, and where nutrients lost from agriculture cause eutrophication of natural waters and are regarded as pollutants.

9.1 INTRODUCTION

The annual production of organic carbon by photosynthesis on land is about 6x 10¹⁰ tonnes (Table 9.1), most of which eventually decomposes on or in the top 50 cm of the soil. This organic matter can be in lumps as big as a mature oak tree (say 0.5xl0²m³) or as small as a bacterium (0.5 x 10~¹⁸m³). It can be in material as resistant to decay as oil palm nuts, which persist for years in soil in the humid tropics, or as transient as mammalian protein. Yet in the long run, no fraction of the organic matter in plants and animals can withstand decomposition to carbon dioxide and water. If this were not so, any completely resistant fraction would by now cover the surface of the earth. Although under normal conditions organic matter does not accumulate indefinitely in soil, exceptions can occur, as, for example, when a soil becomes permanently waterlogged. When a geologically stable surface has been under the same vegetation for a long time, the soil approaches steady state conditions, with the annual losses of organic matter balancing the annual input. Thereafter the organic matter content of the soil remains constant, until the next vegetational change or geological catastrophe. This process, in which losses and gains proceed simultaneously, is described as turnover and may be defined (for carbon) as ‘the flux of carbon through the organic carbon in a given sample of soil’. Turnover time is then the amount of carbon in the soil system (or part of that system) divided by the annual input of carbon into the system (or part of that system). Turnover and turnover time will be discussed more fully in Section 9.2.5.

8.1 INTRODUCTION

The development of a soil profile involves the mobilization of major and minor elements and their subsequent deposition elsewhere in the profile or removal in the drainage water. For a full understanding of these processes we need to know what are the forms and reactivities of the soil constituents, the nature and mode of action of the mobilizing agents, the forms in which the mobilized material is transported—whether colloidal or in true solution, whether in ionic or complex form, whether alone or in association with other soil constituents—as well as its stability towards oxidation and reduction, microbial action, pH, and sorption and coprecipitation. The availability of micronutrients to plants is presumably governed by factors such as these. The current concern with problems of soil contamination has brought to the attention of soil chemists numerous toxic metals that were previously regarded as essentially the province of the geochemist.

It is probably true to say that no one of the factors listed above can be considered in isolation, but so far as any one factor is of dominant importance, this is nature of the mobilizing species; this determines the form in which the metal is transported, and its ultimate fate in the soil or in the drainage water.

This chapter is an attempt to summarize our present knowledge of the processes responsible for the mobilization and immobilization of metals in soils.

7.1 INTRODUCTION

An understanding of the processes of oxidation and reduction in soils and the associated changes and practical implications requires a knowledge firstly of soil respiration and the movement of O₂ and CO₂ in soils, and secondly an appreciation of the significance of the changes which occur when, as a result of the use of all the O₂ in a given zone of the soil, respiration changes from aerobic to anaerobic. This results in marked changes in the biochemistry of the system. A basic knowledge is therefore needed of the microbiology and biochemistry of aerobic and anaerobic respiration and of the physics of gas movement, as well as of the chemistry of the system.

6.1 INTRODUCTION

This chapter is concerned with the interactions which retain mobile chemical species in the soil environment. Emphasis is centred on the binding of small organic chemicals to soil particles of colloidal dimensions, and on the associations between polymeric materials and inorganic colloids which strongly influence the physical and chemical behaviour of soils. These interactions are also involved in the retention by soil of water, discussed by Farmer (1978) in the companion volume to this book, and in ion and ligand exchange reactions, and in mass flow and diffusion discussed in preceding chapters.

The term colloidal refers to particles and discontinuities of matter (e.g. pore spaces or thin films) of dimensions in the range of 1 nm to 1 jxm (IUPAC, 1972). For such finely divided systems the properties of the interfaces are very important because these largely control the behaviour of the colloidal systems. The term phase is used to describe the homogeneous parts of a system and an interface or surface is the boundary region between any two phases; the relevant interfaces are solid/gas, solid/liquid, liquid/liquid, and liquid/vapour. Where none of the solid, liquid, or vapour phases in a system are finely divided the ratios of the interfacial areas to the bulk volumes of the phases are small, and the effects of the interface between neighbouring phases can be neglected.

The most extensive surfaces in soils are contained in domains and micro- aggregates of colloidal particles (cf. Greenland and Hayes, 1978; Greenland and Mott, 1978), These surfaces are accessible from the pore spaces between solid particles. Under normal field conditions these spaces remain filled with water. Thus, although modern fertilizers, and chemicals for the control of plant growth, pests, and diseases are applied to soils as solids, liquids, and gases, most of the interactions with the soil colloidal constituents take place at the solid/liquid interface. We shall be primarily concerned here with uptake from the liquid phase by solid soil components, although interactions at the solid/gas interface can sometimes be important.

5.1 INTRODUCTION

One of the generalizations that can be made about soils is that the particles of which they are composed together have a nett negative charge. There are exceptions: for example, some iron- and aluminium-rich tropical soils can attain a positive charge at low enough pH, but such cases are rare. It is nonetheless a fact that most anions are held strongly by the soil complex, and it is the purpose of this chapter to look at some of the reasons why this is so. Historically, the impetus to research in this area has largely been the practical necessity to understand the behaviour of applied phosphate fertilizer, and it is some indication of the complexity of the problems involved that, even after decades of effort by soil chemists and agronomists, this understanding is still far from complete. The reason for this is partly that the soil surfaces themselves are, as has been described by Greenland and Mott (1978) in the companion volume, the product of a ‘dirty’ environment. This generally means that phosphate added to the system has to exchange on sorption with an inadequately characterized suite of anions presorbed on ill-defined surfaces. There are also in the case of phosphate, possibilities of simultaneous precipitation. Faced with these problems, the trend in the literature over the past ten years or so has been to investigate in detail the physical chemistry of the sorption of anions onto simple surfaces which are fairly well understood, in the expectation that this will lead to ultimate comprehension of behaviour in the natural system. The results of many relevant experiments have only recently been published, and so some parts of the account are still at the discussion stage in the literature. This is especially true of phosphate, which looks destined to be a joker in the anion pack for some time to come.