eChapters

Green manure is defined as fresh organic matter/undecomposed plant material/ real organic matter, natural plant food added to the soil for the purpose of supplying plant nutrients.

CLASSIFICATION OF GREEN MANURES

Nonlegumes: Rape seed, buck wheat, niger, rye, oats and maize

Legumes:

Grain legumes: cowpea, mungbean, pigeon pea, soybean, khesari (Lathyrus sativus)

Dual purpose legumes: cluster bean (Cyamopsis tetragonoloba). pillipesara, Sesbania speciosa.

Non grain legumes: sunnhemp, dhaincha, pillipesera (Phaseolus trilobus), stylosanthes and desmodium.

Introduction 
Nanotechnology has become a highly influential field in science, showcasing diverse applications and promising trends over the past few years. Nanoscience has been a source of inspiration for material science researchers, encouraging the exploration of innovative methods to synthesise novel structures with significant properties and applications(Kolahalam et al. 2019). Nanoparticles are the core of nanotechnology, with “nano” denoting sizes smaller than a billionth of a hair, specifically below 100 nm (Volath et al. 2008).The focus on small-sized nanoparticles (1–100 nm) has become a global research priority attributable to their remarkable applications in physical, chemical, and biological sciences (Jeevanandam et al., 2018). The term “nanotechnology” was coined by Nobel Prize-winning physicist Richard Feynman in his renowned 1959 lecture titled “There’s Plenty of Room at the Bottom.”(Boverhof et al., 2015).Feynman proposed the advanceof smaller devices down to the molecular scale, asserting that it was not the laws of nature but rather the lack of appropriate equipment and approaches that limited progress in working at atomic and molecular scales(Clunan et al., 2014). In recent times, nanotechnology has transitioned into a mainstream and crucial innovation. When materials are manipulated at the nanoscale, their properties undergo significant transformations, leading to remarkable applications in physics, space science, chemistry, medicine, energy renewal, healthcare, environmental science, mechanics, electronics, civil engineering, optics, and more [Figure. 1](Mourdikoudis et al., 2018; Joshi et al., 2008; Suresh Kumar et al., 2019); AarthyePandian et al., 2019).

Introduction

Soil is a non-renewable resource that sustains life, providing ecosystem services such as biomass production, contaminants filtration, raw material supply, nutrient, and hydrological cycle (Panagos et al., 2020). It contributes about 95% to global food production (Borrelli et al., 2020). Soil is a major global biodiversity pool and a large carbon pool on Earth. Therefore, it plays a crucial role in regulating energy and mass flow and their transfer between the biosphere, lithosphere, hydrosphere, and atmosphere (Ferreira et al., 2021). Climate change and unsustainable management practices are threatening the soil’s natural capital resulting in soil degradation occurring simply from erosion to contamination and leading the soil to completely unproductiveness under severe conditions, leading to food insecurity (Ashoka et al., 2017; Syed et al., 2022)

Tourism is a phenomenon, which has taken off immensely in the past three decades. It concerns us all, be it by allowing us to travel long distances as tourists, or by forcing upon us a mass of visitors to our part of the world. In the past, people did not travel half as much. Financial obstacles and responsibilities to land and animals stopped them from doing so. Only in 1845 did Thomas Cook of Leicester, England, organize the first package tour, making this experience available to people outside of the privileged classes by cutting down on expenses. By 1939, an estimated one million people were traveling abroad each year. Nowadays, the population of the Mediterranean swells to double over the summer, from 130 million resident inhabitants during the winter to 260 million in high season. There were about 698 million international tourist arrivals worldwide in 2000. All regions in the world grew, and the fastest developing region continued to be East Asia and the Pacific. Tourism has become the largest industry in the world. And just like all thriving industries, though it has a lot to give, it also takes a lot in turn. Unfortunately, the toll that we pay for it has been rising steadily. While the prospect of people traveling less in the future seems improbable, to say the least, a new idea has already sprung up: If we cannot stop tourism, let us at least travel sensibly.

1.1 Introduction

Greenhouse effect, regulated by the presence of greenhouse gases in the earth’s atmosphere, is a natural process that plays a major part in shaping the earth’s climate. A continued rise in concentration of the greenhouse gases has led to enhanced greenhouse effect resulting in global warming and global climate change. The impact of human activities on greenhouse gases (GHGs) emission through fossil fuel burning, agriculture and industrial processes is important and familiar to people. This chapter addresses basic principles and physics of greenhouse effect and the role of Indian agriculture in GHG emissions. Agriculture is a potential source and sink to GHGs in atmosphere. It is a source for three primary GHGs: CO₂, N₂O and CH4 and sink for atmospheric CO₂ . Management of agricultural land, land use change and forestry has a profound influence on atmospheric GHGs concentration. The two broad anthropogenic sources of GHGs emission from agriculture are the energy use in agriculture (manufacture and use of agricultural inputs and farm machinery) and the management of agricultural land. Large sections of the India’s population depend on biomass resources like wood, crop residues and cattle dung for energy. In the agriculture sector, besides the CO₂ emissions due to burning of crop and animal waste, India’s large ruminant population and rice fields are significant contributors to CH₄ emissions. An understanding of GHG emissions by sources and removal by sinks in agriculture is important to take appropriate mitigation and adaptation strategies and to estimate and create inventory of GHGs.

Introduction

Precise and continuous measurement the greenhouse gases (GHGs) fluxes/ emissions in agricultural systems are required for accounting and budgeting of carbon. Further, the long-term measurements of GHGs fluxes are equally important as precise measurement. Therefore, high frequency and long-term measurement of GHGs across the cropping systems are essential for chalking out the GHGs emissions mitigation strategies. Various technologies with definite working principles are used for estimation of GHGs emissions in agriculture.

Greenhouse Gases Estimation Techniques

Two basic principles are followed to estimate greenhouse gases in agriculture. One is the collection of GHGs from the field and subsequent analysis of the concentration of gases through gas chromatography (GC). Another principle is based on sensors measurement with the help of infrared gas analyze (IRGA). The two techniques used for the measurement are (i) ‘closed chamber method’ (manual/automatic), and (ii) ‘sensor-based method’. Generally, the GHGs fluxes in agricultural crop field are estimated by ‘closed chamber method’ for methane (CH₄) and nitrous oxide (N₂O). And for carbon dioxide (CO₂) measurement either soil respiratory chamber or canopy chamber is used that measures CO₂ with the help of infrared gas analyzer (IRGA).

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 Chemistry of greenhouse gases (ghgs)

Greenhouse gases (GHGs) are atmospheric-gases that have capabilities to absorb and radiate-back the infrared (IR) radiation in the earth-atmosphere system (Figure 3.1). In this process the atmospheric-gases absorb and radiate- back IR radiation in lower atmosphere effectively emitting and absorbing heat energy heat energy. They maintain the heat budget of earth-atmosphere and keep our plant warm. If we typically see the chemistry of those gases, the key point is that they should have dipole moments. This is the property which makes them capable to absorb and radiate-back the range of IR radiation. In a molecule when valence-electrons are not equally shared in a bond between the two atoms, a slight positive charge is developed above one atom and a negative charge on the other atom. That charge difference of the different atoms in a molecule generates the dipole moment. For instance, in water vapour (H₂O- vapour), an unequal sharing of electrons and or separation of charge causes dipole moment. In H₂O, the centre has a positive charge at the hydrogen atoms and negative charges are located on the oxygen atom. The magnitude of dipole- charges, vibration and stretching of O-H bond generates certain frequency of the oscillating dipole moment that actually regulates the absorption capacity of IR radiation by H₂O vapour.

Naturally Greenhouse gases are cover as blanket on the Earth and kept it about 33⁰C warmer than it would be without these gases in the atmosphere. This is called as the “Greenhouse Effect”.

Over the past century, the Earth has increased in temperature by about 0.5⁰C and many scientists believe that this is because of an increase in concentration of the main greenhouse gases viz., carbon dioxide, methane, nitrous oxide and fluorocarbons. People are now calling this climate change over the past century the beginning of “Global Warming”.

Landscaping is both science and art and is an aspect of the environmental impact of a hotel that needs to be addressed. Understanding and blending the elements of both nature and construction is effective landscaping. Whether Landscaping is extensive or small consumes a large amount of water, fertilizers and herbicides and generates solid waste.

Ecogreen’s Greenscaping Operation provides cost-efficient and environmentally friendly solutions for landscaping. Greenscaping operation deals with two aspects:

1. Solid Waste Management, and

2. Water Conservation

This chapter deals with the findings of the study along with the discussion based on the analysis. This study tried to represent its findings as per the objectives of the study. At the end of this chapter, interrelation has been made, an explanation has been tried to put out down and an attempt has been done to reveal the cause behind it. The results and their pertaining discussion are presented according to the specific objectives of the study.

Introduction

Large scale exploitation of groundwater using modern deep well boring technology and powerful pumps is the order of the day in India and elsewhere. Increase in agriculture area and year around cultivation of water intensive crops, frequently failing monsoons (Fig.5.1) all have led to drying up of surface water and increased dependence on groundwater.

Thus, given the scenario of over exploitation of the available groundwater, it is essential that proper storage and management of available groundwater resources be identified.

Introduction

The science of hydrogeology is defined as hydrology with emphasis on geology. This chapter is to refresh your geology knowledge. The key words are highlighted to assist a quick review.

The Crust and its Composition

The thin outermost layer of the earth is called the crust and ranges in thickness from about 8 km under the oceans to about 25 km on land. It extends under both oceans and continents, and forms the source for all the soils, vegetation, and gases in the atmosphere.

The crust is primarily composed of two elements: silicon and oxygen which account for 75% of the earth’s crust. Note that these are the two elements found in quartz (e.g., sand), which suggests this is the most common of all minerals.

Introduction

Groundwater investigation has a long history. In the past a waterman in the village would walk around the investigation area with a Y shaped wooden fork and identify the location for digging the wells. Certain trees and organic landforms like termite mounds were considered as indicators. The native intelligence of local topography should have played a role in identifying potential location. Successful or otherwise the method can be said to lack scientific objectivity. The optimal groundwater surveying method is no doubt drilling. This method ensures that all necessary information is being brought up from the geological formations. However, in order to obtain a desired degree of information from the subsurface of an area, drilling alone is normally not a feasible alternative.

There are a number of efficient and inexpensive geophysical surveying methods available to the hydrogeologist. It is worth noting at this point that these are, without exception, indirect methods. This implies that no method measures directly what we are actually looking for. With geophysical surveys, the target features are therefore invariably associated features. This implies that unless we understand the water context of these features, our geophysical surveys will be less than meaningful.

Objective methods of investigating groundwater are discussed in this chapter.

Groundwater is a precious renewable resource which gets replenishment from the precipitation. Total water resources of the world are estimated at 1.37 x 10⁸ million ha-m. Of these, about 97.2% is salt water, mainly in oceans, and only 2.8% is available as fresh water. And, out of this 2.8%, about 2.2% is available as surface water (2.1% is fresh water in glaciers and icecaps, 0.1% is available in lakes and reservoirs, 0.0001% in streams) and 0.6% is available as groundwater. Only 50% of groundwater resource is economically extracted with available technology. Presently, 1.3 x 10⁴ million ha-m fresh water in reservoirs and 41.1x10⁴ million ha-m groundwater is theoretically available to provide usable water for drinking, domestic use, irrigation, etc., to mankind. Groundwater is the largest source of fresh water excluding the polar icecaps and glaciers. The amount of groundwater within 800 m from the ground surface is over 30 times the amount in all fresh water lakes and reservoirs, and about 3000 times the amount in stream channels, at any one time.

Introduction

Fresh water, a renewable but not an infinite resource, is becoming increasingly scarce. The amount available for use to the world today is almost the same as it was 4500 years ago but global demand has been increasing exponentially. Since 1950, the renewable supply per person has fallen 58 percent as world population has swelled from 2.5 billion to 6 billion. Moreover, unlike oil and most other strategic resources, fresh water has no substitute in most of its uses. It is essential for growing food, manufacturing goods, and safeguarding human health.

According to a World Policy Forum report, the largest and most combustible imbalance between population and available water supplies will be in Asia, where crop production depends heavily on irrigation. Asia today has roughly 60 percent of the world’s people but only 36 percent of the world’s renewable fresh water. China, India, Iran, and Pakistan are among the countries where a significant share of the irrigated land is now jeopardized by groundwater depletion, scarce river water, a fertility-sapping buildup of salts in the soil, or some combination of these factors. Groundwater depletion alone places 10 to 20 percent of grain production in both China and India at risk.

Introduction

All models are but approximations of reality. When we approximate there is always room for uncertainty. The preference of a particular model over the other is the relative degree of uncertainty acceptable to the objective and budget of the study. With the advent of computers, hosts of modeling software promising a lot to the researcher have arrived on the horizon. It is not in the scope of the book to enumerate all the techniques of hydrogeological modeling. Physical modeling using sand tanks was the earliest attempted modeling technique, about 107 years ago. Most recent and significant modeling technique practiced by many in groundwater potential identification is Geographic Information System (GIS) based modeling. After a brief treatment of physical models, concepts of mathematical models and GIS modeling are elaborated. The modeling techniques have involved mathematics and or software specific instructions. Hence it is recommended that relevant text books for individual techniques be referred. This chapter deals more on modeling concepts.

Key words : Groundwater Modelling, GIS, PMWIN, ArcInfo Interface Con2grid, Interface Programme, ArcMacro Language.

Introduction

Groundwater is an important source of irrigation in India and has played a major role in increasing the food production. About 50 per cent of total irrigated area in the country is dependent on groundwater (Central Water Commission (CWC), 2000). Productivity of groundwater is normally more than the surface water due to the fact that it is available at the point of use, requires minimum conveyance infrastructure, is available on demand and maximizes the application efficiency. However, in past few years, excessive and unplanned groundwater pumping in certain parts of the country has resulted in depletion of groundwater resources. Water table in these region is going down day by day and making it beyond the reach of poor farmers. Therefore, keeping the water table in the desirable range is a major concern. This can be achieved by adopting proper pumping rate and pumping schedule. Groundwater modelling has successfully been used for deciding the pumping rate and pumping schedule. Groundwater modelling refers to simulation of groundwater behaviour under varying pumping and recharge conditions. A groundwater model is simply a set of equations, which describe the physical processes active in the aquifer subjected to certain assumptions. While the model itself obviously lacks the detailed reality of the groundwater systems, the behaviour of the validated model approximates that of the aquifer.

Introduction

Water is one of the most complex natural resources demanding a comprehensive understanding of its inherent features in occurrence and distribution for an integrated planning aimed at optimum development for agriculture, health, industry, power, etc. The well being and development of our society is dependent on the availability of water. An increase in groundwater development and utilization for industries and urban water supply has created improper disposal of liquid waste. Defective well constructions, sewage and waste disposal in man made lakes within city, open quarries with water and failure to seal the abandoned wells in city area have provided possible openings for downward movement of polluted water into subsurface formations without undergoing the process of natural filtration.