eChapters

This chapter introduces soil testing as an essential component of scientific nutrient and land management. It traces the establishment and expansion of soil-testing laboratories in India and explains their role in assessing soil fertility, productivity and physical, chemical and biological conditions. Soil testing helps determine suitable fertilizer and amendment requirements while preventing the excessive or unbalanced application of nutrients. The chapter emphasizes that fertilizer recommendations must reflect differences among soils and fields. It also introduces representative soil sampling as the foundation of dependable laboratory results and outlines important precautions concerning equipment calibration, clean glassware, contamination prevention and safe laboratory practices.

Arsenic contamination is one of the serious concerns for public health throughout the world. During the weathering of rocks and minerals, which are followed by subsequent leaching and runoff, arsenic (As) is released into the soil and groundwater. Additionally, human sources can transfer it into the soil and groundwater. Depending on the geological settings, geochemistry, and geo-environmental conditions of an aquifer, different aquifers may have different adsorption and desorption processes, arsenic species, Eh, pH, solid phase dissolutions, and precipitations. Therefore, rigorous geochemical investigation for an adequate understanding of arsenic geochemistry under different hydrogeological and geo-environmental conditions of aquifers is essentially required for evolving sustainable solutions. All of the arsenic affected river plains have river routes originated from the Himalayan region. Arsenic in groundwater contamination has far-reaching consequences including its ingestion through the food chain, which are in the form of social disorders, health hazards and socioeconomic dissolution besides its sprawling movement, and exploitation of groundwater. Food crops produced with arsenic tainted water are marketed to other locations, including areas where people may eat the tainted food and be exposed to arsenic. The arsenic contamination of groundwater is a form of groundwater pollution which is due to naturally occurring high concentrations of arsenic in deeper levels of groundwater.

1. The unconsolidated mineral or organic material on the immediate surface of the Earth that serves as a natural medium for the growth of land plants. - Soil Science Society of America

Metals are toxic and non biodegradable pollutants released into the environment through effluents from agriculture waste, mining, metal processing industries, pharmaceutical industries as well as domestic and natural activities. Metallic pollutants tend to persist indefinitely and eventually get accumulated in the ecosystem. Metals especially arsenic, copper, cadmium, chromium, lead, mercury, nickel, selenium and silver etc. possess a risk to living systems. Conventional processes applied to remediation of metallic pollutants are often restricted due to technical and economical constraints. Particularly when the metal contamination is at very low concentration the conventional methods become inefficient. In this situation application of bioremediation techniques is a technology of choice for environmental protection and clean up.

Remote Sensing in Oil Exploration

Remote sensing plays a significant role in the oil exploration industry. It refers to the use of sensors and instruments to gather information about the Earth's surface and its environment from a distance. This information can be used to locate and evaluate oil and gas deposits.

There are different remote sensing techniques used in oil exploration, including

Seismic surveys: This technique involves creating sound waves underground and recording their reflection to determine the subsurface structure. It is commonly used in oil exploration to locate potential oil and gas deposits.

Magnetic surveys: This technique uses a magnetometer to measure the magnetic field of the Earth's surface. Magnetic anomalies can indicate the presence of underground geological structures that may contain oil or gas deposits.

Gravity surveys: This technique involves measuring variations in the Earth's gravitational field, which can indicate the presence of underground geological structures.

Practice to calculate the weight / volume of reagents required to prepare the following standard solutions.

Preparation of Standard Solution - (1 M, 0.1 M, 1 N, 0.1 N, 0.5 N, 5%, 10%, 20%, 10 ppm, 20 ppm, 100 ppm)

5.1 Volumetric Techniques or Titrimetric Analysis

Acid Base Neutralization Reactions-Acidimetry & Alkalimetry

Oxidation –Reduction Reactions-Oxidometry (Permanganometry) & Dichrometry

Principle

Equal volumes of all acids / bases containing their gram equivalent weights per litre of the solution react completely with each other.

Principle

Soil moisture content is determined by drying a known quantity of soil sample in an electric oven at 105° C to 110° C and finding out the loss in weight.

Bulk density is the mass per unit volume of soil including pore space. The normal range of bulk density in most soils is ranging from 1.02 to 1.80 g / cm³. The bulk density of coarse textured soils will be on the higher side while organic soils will have lower bulk density.

Particle density is the mass of soil per unit volume excluding pore space. Pore space is that fraction of soil volume not occupied by solid particles.

Principle

The bulk density and percent pore space are determined from the apparent and true volumes of the soil measures by adding a known quantity of water to a measuring cylinder contain a weighed quantity of soil.

(Keen-Rackzowski/Hilgard Apparatus Method)

Principle

With the capillary rise of water, the soil immediately above a water table gets saturated. The height upto which the soil is saturated depends on the texture, structure and packing of the soil mass. The experimental technique discussed herein permits approximation of maximum water holding capacity while determining the amount of water held in the soil at the point of saturation.

The pH is defined as negative logarithm of hydrogen ion concentration or the log of the reciprocal of the hydrogen ion concentration (Sorenson, 1906).

Principle

A glass electrode in contact with hydrogen ions of the solution acquires an electric potential which depends on the concentration of hydrogen ions. This is measured potentiometrically against some reference electrode which is usually a calomel electrode. The potential difference between glass electrode and calomel electrode is expressed in pH units.

Two electrodes are used in the determination of pH. One is reference electrode which provides a standard voltage and is usually a saturated calomel electrode which has two layers of saturated solution of KCl and mixture of solid HgCl₂ and Hg. The outer tube is usually 5-15 cm long, 0.5-1 cm in diameter. The mixture of solid HgCl₂ + Hg paste is contained in an inner tube that is connected to the saturated KCl solution in the outer tube by means of small opening. The resistance developed by this type of electrode is 2000-3000 Ohms.

The outer electrode is glass electrode that consists of a tube enclosing a lead wire made up of Ag coated with AgCl. This wire is again enclosed in a wax insulation. To the tube at the bottom is attached a glass bulb made up of a special kind of glass which is sensitive to hydrogen ions. The thickness of the glass membrane varies from 0.03 to 0.1 mm and has a resistance of 50 to 500 mega Ohms.

When these electrodes are dipped in solution, the saturated solution of KCl comes out of reference through small holes and forms an invisible ionic bridge between electrodes through which current passes. The hydrogen ions are absorbed by glass electrode and depending upon the amount of hydrogen ions present in the solution, an electric potential develops between electrodes. This potential difference is measured in terms of pH units by suitable Galvanometer.

The Electrical Conductivity (EC) of the soil is a measure of soluble salts present in the soil and is expressed as millimhos/cm or dSm^-1.

Principle

As the amount of the soluble salts in a solution increases, the electrical conductivity also increases. This electrical conductivity is measured in terms of resistance offered to the flow of current using a conductivity bridge.

It is known that solutions offer some resistance to the passage of current through them, depending upon the concentration of the soluble salts present. Hence, EC is measured in terms of electrical Resistance between parallel electrodes immersed in the soil water suspension.

In such a system, the solution between the electrodes becomes the electrical conductor to which the physical laws relating to resistance are applicable. The electrical resistance ‘R’ is directly proportional to the distance ‘L’ between the electrodes and inversely proportional to the cross sectional area ‘A’ of the conductor.

OBSERVATION

The examination of the IRS - 1A imagery under raw and the digitally enhanced modes vividly display heavy concentration of suspended sediments in certain sectors along the east coast of Tamil Nadu. Such pockets of suspended sediments are seen as long and linear bodies trending parallel to the coast to the strike length of 20 - 30 km and width of 5 - 10 km. Such Phenomenon of suspended sediments concentration are strikingly observed in two sectors. One in between Tuticorin harbour and Vaippar river mouth and the other just at the mouth of Ponnaiyar river along Cuddalore-Pondicherry coast. Both of them are observed along conspicuous (Fig.1& 2) concave coasts.

This chapter explains how representative soil samples should be collected, labelled, transported and prepared for analysis. It identifies essential sampling equipment, including spades, khurpis, augers, trays, sampling bags, markers and polythene sheets. The recommended procedure involves dividing land into uniform sampling units, collecting soil from several well-distributed locations and combining these portions into a composite sample. The chapter describes V-shaped sampling cuts, suitable sampling depths and sample reduction through quartering. It also lists the field information that should accompany each sample. Procedures for air-drying, grinding, sieving and mixing samples are presented, together with precautions for avoiding unusual areas and contamination.

Introduction
The study of energy flow through the ecosystem is known as Ecological Energetic. Ecological Energetic is the scientific discipline that investigates the movement ofenergy within an ecosystem. The process of energy transfer that takes place within a food chain is referred to as energy flow. The functioning of all species in an ecosystem is dependent on the energy they derive from the energy flow. The ecosystemsustains itself and achieves stability through the process of energy transfer.
Energy Transfer/Flow
Solar energy is the primary source of energy that enters the food chain at the level ofproducers, which are plants. Through the process of  photosynthesis, plants utilize solar energy to transform it into chemical energy, which is then used to produce various components of plants such as leaves, flowers, fruit, branches, trunks, and roots. Plants are referred to as producers in the ecosystem because they have the ability to transformthe sun’s energy directly into their tissues, allowing them to thrive. Herbivores consume the plants as nourishment, so obtaining energy. A significant portion of this energy is expended on the metabolic processes of these organisms, including respiration, digestion, tissue growth, blood circulation, and body temperature regulation. Energy is also expended in activities such as foraging, seeking refuge,reproducing, and nurturing offspring. The predators rely on the herbivores as their source of food.

Introduction

In India there are about 200 distillery having installed capacity 1555.5 million liters per annum out of which 50% are of 30 KL/ per day capacity about 50% of remaining distillery are of 45 to 60 KL/ per day capacity there are few distilleries which having go 120 KL/ per day capacity. Distillery waste is one of the major industrial waste having high organic and inorganic constituents in the recent past the treatment and disposal of distillery waste has become a subject of debate of each and every forum.

The resources on the land have started showing sign of faster depletion owing to the population explosion, over exploitation of mineral and water resources and also the improper exploitation and the related wasting of the natural resources. Hence a time has come to search for more and more newer natural resources amongst which the ocean resources gain supreme importance as this treasure is yet to be hunted due to the non - availability of suitable technology for the same.

Such ocean resources mainly include the mineralogical and biological resources. The ocean biological resources, their birth, growth, population and migration greatly depend as chlorophyll content, total dissolved oxygen, total suspended solids, salinity etc. These parameters which constitute the marine environment drastically change in a quick span of time owing to the dynamically changing marine forces.