eChapters

We do not know when intercropping began nor why early civilizations fostered its use. Whether by design or accident, intercroppinq dominated early agriculture and is still practiced in many areas of the world. With the advent of “modern” agriculture, intercropping began disappearing from many areas. This shift was driven primarily by mechanization and specialization. Despite pressures to abandon intercropping, it has survived and flourished Inereasing interest in sustainability and environrnental concerns have drifted attention back to intercropping as a means of better utilization of resources while preserving the environment.
Through intercropping, farmers can achieve the full production of the main crop and also an additional yield (bonus) associated with an increased plant population of the second component. Hence, intercropping can increase incomes obtained by smallholder farmers in areas where labor is not shortage, through reduction of economic risk and market fluctuation resulting from growing a single crop which is more prone to natural hazards and helping the farmers in better utilization of land by having more than one crop produced per unit area. Though all intercrops produced higher productivity, the farmers could better use the appropriate population of component crops in intercropping systems in order to maximize yield of both crops as well as total productivity. It is, therefore, important to support intercropping systems with appropriate agronomic practices such as timely irrigation, pest protection and the likes to sustain the cropping system in the countries where labor is not problem for proper management in general even though sometimes sole cropping may became more productive.

MOST OF THE ENERGY FOR LIFE COMES FROM SUNLIGHT

Total rate of energy delivery from sun to earth (at the top of the atmosphere) = 175,000 terrawatts

Terrawatt = 10^12 watts

Rate of energy capture by plants from the sun = net primary productivity (NPP) = 100 terrawatts

Only ~ 0.06% of sunlight is captured

Captured in chemical bonds, especially in sugar

Small amounts of energy are available to specialized microorganisms from chemical reactions not linked to sunlight

It is estimated that 99% of the energy used by living cells comes from the sun

Incorporation of sunlight into chemical bonds occurs through the process of photosynthesis

“Invented” by cyanobacteria about 2 billion years ago

Photosynthesis- the word photo refers to light and synthesis means preparation. Thus, photosynthesis is the process by which the green plants use light energy of the sun to synthesize carbohydrates. Carbohydrates like simple sugars (glucose) can be stored as starch.

The green plants are eaten by the herbivores, which in turn are consumed by carnivores. Ultimately, the decomposers derive their nutrition from the dead plants and animals. Thus, all organisms are dependent directly or indirectly on green plants, which synthesize food by photosynthesis. Thus, photosynthesis is the most important life sustaining process of nature (Calvin, 1976; Emerson and Arnold, 1932). Photosynthesis is a series of biochemical reactions, which can be essentially summarized as follows:

Photosynthesis is a very important parameter in plant physiological studies. It is the only process in nature which utilizes solar energy and converts it into chemical energy. It has a direct bearing on plant productivity. By understanding the process of photosynthesis, manipulation of productivity can be made possible.

1. Measurement of Photosynthesis Rate

Measurement of CO₂ uptake provides an alternate and direct method of measuring productivity, with important advantages over measurements of change in dry weight. It is instantaneous and non-destructive.

Infra Red Gas Analyzer (IRGA) is an equipment which is most widely used for the measurement of photosynthesis in situ in the field or in detached leaves under laboratory conditions. It is less time consuming and reliable. It can also be used for the measurement of rate of respiration and CO₂ compensation concentration (CO₂ CC), provided a little alteration is made in the chamber.

1. Introduction
Water is the most essential resource for life, supporting the survival of allliving beings, including humans, and playing a crucial role in food productionand economic progress. Currently, many cities around theworld are facingsignificant water shortages. About 40 % of global food production dependson irrigation, and countless industrial operations rely heavily on water. Theavailability and quality of water, whether surface or groundwater, have amajor impact on environmental health, economic development, and societagrowth. Human activities like urban expansion, population increase, industrialoutput, and climate shifts are causing a decline in water quality. As nationsdevelop, industrial activities increasingly lead to the pollution of watersources, resulting in negative consequences such as widespread disease and
diminished beauty of water bodies. This pollution is a significant threat toboth the planet and its inhabitants. Higher temperatures are interfering with themetabolic processes of aquatic life, while changes in water pH create unstableconditions. Additionally, increased cloudiness in water reduces oxygen levels,affecting deep-water species and contributing to health issues for both animalsand humans. Polluted water also hinders growth and development in allliving organisms Haldar et al., 2015 and Arif et al., 2020. A study conductedby Halder et al. (2015) highlighted severe health challenges faced bylocalcommunities due to pollution in the Turag River, Dhaka, caused by thedischarge of untreated wastewater into the river. It was revealed that elevatedpH levels in the water, resulting from the use ofcaustic chemicals such assoda ash and caustic soda in industrial processes, were associated with skinirritation and sores. Dietary exposure to polluted crops and fish was found
to contribute to stomach ailments, including gastric ulcers. Concerns wereraised about potential groundwater contamination through the infiltration ofindustrial waste. Microbial contamination was identified as a likely cause ofdiarrhoea and dysentery. The use of river water for bathing and laundry wasobserved to facilitate the spread of waterborne diseases. Outbreaks of yellow
fever, cholera, dengue, malaria, and other epidemics were noted as prevalent inthe area. Respiratory problems and foul odours were attributed to air pollutioncaused by industrial discharge. Maternal and child health in riverbank slumsfound to be vulnerable, emphasizing the urgent need for interventions to addressthese public health concerns.Wastewater produced by industries, agriculture,and domestic activities contains high levels of nutrients, heavy metals, andchemicals, which harm the environment by polluting land, air, and water,

Abstract

Photosynthetic blooms of toxin producing marine algae are often referred to as “red tides”. Proliferations of freshwater toxin-producing cyanobacteria are simply called “cyanobacterial blooms” or “toxic algal blooms.” Biotoxins of cyanobacteria are water-soluble and heat stable and they are released upon aging or lysis of the cells. The primary types of cyanobacterial biotoxins involves three types of toxins: hepatotoxins (microcystin; cylindrospermopsin and nodularin), which are taken up by the liver and cause weakness and anorexia (loss of appetite); neurotoxins (usually anatoxin and saxitoxin), which effect the nervous system and dermatotoxins (aplysiatoxin and lyngbyatoxin, LPS), which cause skin and mucous irritations upon contact. Unlike freshwater toxic algal blooms, marine algal toxins become a problem primarily because they may concentrate in shellfish and fish that are subsequently eaten by humans, causing syndromes known as paralytic shellfish poisoning/PSP (paralysis due to saxitoxin and gonyaulatoxins), diarrhetic shellfish poisoning/DSP (diarrhea due to okadaic acid) , amnesic shellfish poisoning /ASP(memory disturbances due to domoic acid), neurotoxic shellfish poisoning/NSP (paresthesia due to brevetoxin; also bronchial spasms). Coral reef fishes are the vectors of another algal poisoning, the ciguatera fish poisoning/CFP (paresthesia, warm-cold sense inversion etc., due to ciguatoxins and maitotoxin).

Botany

Phyllanthus is an herb common to Central and Southern India. It can grow to 30–60 centimeters in height and blooms with many yellow flowers. All parts of the plant are employed therapeutically. It is a small erect annual herb 10-60 cm tall widespread in tropical areas. Leaves are small elliptical - oblong and flowers are whitish green & minute. It bears ascending herbaceous branches. The bark is smooth and light green. The fruits are tiny, smooth capsules containing seeds.Kizhanelli is a circum-tropical weed, thriving well under tropical conditions. In India, it grows abundantly up to 700m altitude in Punjab, Haryana, Uttar Pradesh, Bihar, West Bengal, Orissa, Madhya Pradesh, Maharashtra, Andhra Pradesh, Karnataka, Tamil Nadu and Kerala.

Major constituents – Phyllanthin (0.4-0.5%) and Hypophyllanthin

Uses- Hepatitis B and Jaundice

9.1. Origin and distribution

• Originates in Tropical America

• Distributed in all tropical and sub-tropical regions

9.2. Economic importance

• Economic part - Whole plant

• Phyllanthin (0.4-0.5%) and hypophyllanthin

• Antioxidant with free radical scavenging properties due to presence of high levels of super oxide dismutase.

• Effective in treatment of peptic ulcer, dyspepsia, diabetes etc.

• Treatment of Hepatitis B and j aundice

Keeping the medical, ecological and economical importance of nematode phylum in mind, it is remarkable to see that nematode systematics is far from established. It has a long history of constant revision and there may be as many classifications as there are nematode taxonomists. Ferris and Ferris (1987) anticipated about the growing sense of excitement pervading systematics as new techniques make it possible a depth of understanding of phylogenetic relationships and affinities never before thought possible. They further stated that Darwin’s ‘genealogical taxonomy’ based on the concepts of descent with modification, is linked directly with two approaches to phylogentic inference, viz., phonetics and cladistics. In both these, patterns of descent take precedence over processes and in classifications based on these procedures, ‘grades’ and ‘gaps’ beloved by the evolutionary systematics are ignored and categories are usually of lesser importance. The phonetic approach deals with ‘natural classification’ based on overall similarity and the belief that the more characters a classification is based on, the more reliable it will be.

1. Botanical Name : Physalis minima Linn.

2. Family : Solanaceae

3. Common Name : Ground Cherry, Sun berry

4. Name in Indian languages

Rasbhari, Chirpati (Hindi), Chirboti, Ran-popti (Marathi), Kupanti (Tamil), Notinotta (Malayalam), Kupanti (Telugu), Gadde hannu (Kannada), Bantepariya (Bengali), Popti (Gujarati).

5. Description

Sunberry is an erect, much-branched, annual plant growing around 50cm tall. The edible fruit is sometimes gathered from the wild and used locally. This is a popular wild fruit to pick and eat. The taste of the ripe berry is sweet and distinctive. The berries are ripe when the husk turns brown and the berry inside takes on a yellowish cast. The plant also has a range of medicinal uses. Physalis minima is commonly found on the bunds of the fields, wastelands, around the houses, on roadsides, etc. where the soil is porous and rich in organic matter. It is an annual herbaceous plant having a very delicate stem and leaves.

Introduction to Nano-materials

Nano-sized materials are naturally present from forest fires and volcanoes, but are also generated unintentionally from anthropogenic sources as a by-product of combustion and deliberately as manufactured nanomaterials. Nanoparticles have been used for centuries. The coloured glass that we see in many old cathedrals from the middle age was made of gold nanosized clusters that created different colour depending on the size of the nanoparticles. The most prominent example of engineered nanoparticulate material is carbon black which has been around us for decades in applications like printing inks, toners, coatings, plastics, paper, tires and building products.
 
Two of the major factors why nanoparticles have different properties (optical, electrical, magnetic, chemical and mechanical) than bulk material are because in this size-range, the quantum effects start to predominate and the surface area to volume ratio is increased.

Milk is a complex colloidal dispersion, the physical and physicochemical properties of which depend on intrinsic compositional and structural factors, extrinsic factors such as temperature, and post-milking treatment.

There is no clear dividing line between physical properties and physicochemical properties. However, physical properties may be thought of as the measure of the bulk behaviour of milk and of how milk interacts with energy, while physicochemical properties are measures of how bulk behaviour and energy interactions depend on the constituent colloidal particles, molecules, atoms and ions in milk.

Knowledge of physical properties is of importance particularly in the technological and engineering design and control of milk processes and processing equipment. Knowledge of physicochemical properties provides the basis for the design of modern methods of milk analysis, determination of milk microstructures and elucidation of the complex chemical reactions that occur in milk.

In the dairy industry measurements of the physical properties of milk and milk products are made to secure data necessary for the design of dairy equipment (e.g., heat conductivity and viscosity) to determine the concentration of a component (e.g., specific gravity to estimate solids-not-fat or freezing point to determine added water), or to assess the extent of a physical or chemical change (e.g., titratable acidity to follow bacterial action or viscosity to assess aggregation of protein micelles or fat globules). The great advantage of physical measurements for such purposes is their speed and simplicity as well as their potentialities for automation.

Use of physical property to measure concentrations or changes in degree of dispersion demands knowledge of the contribution of the several components to that property. Furthermore, the natural range of variation of the property in milks or products is of major interest. The precision and suitability of possible methods of measurement are also of prime importance.

Physical Chemistry of Foods

    1.    Thermodynamics is primarily concerned with energy and entropy. Energy, also called internal energy (U), comprises heat and work; it is measured in joules (J).

    2.    Energy may be recalled that work generally equals force times distance (in N_·m = J) and that force equals mass times acceleration (in kg ·m· s^-2 = N).

    3.    According to the first law of thermodynamics, the quantity of energy, i.e., heat (q) work (p) potential energy, is always preserved.

    4.    Entropy (S)  is a measure of disorder; it is given by   
        S = K_B ln Ω
        Where K_B is the Boltzmann constant (1.38 ×10^-23 J × K^-1) and W is the number of  ways in which the system can be arranged, also called the number of degrees of freedom.

    5.    Colligative solution properties : The lowering of the chemical potential of a solvent by the presence of a solute causes changes in a number of physical properties: vapor pressure, boiling point, freezing point, osmotic pressure, etc. (the magnitudes of these changes all are proportional to the mole fraction of solute).

10.1 Different practices for different purposes

There are so many different practices used in erosion control that to describe them needs some form of grouping. For a long time mechanical protection was used to describe all the methods which involved earth moving, such as digging drains, building banks, levelling sloping land, and so on. Anything else was lumped together under biological methods for want of a better title.

This is appropriate for large mechanized farms where the approach is to use machines to do the earth-moving and follow up with improved farming methods. But this division does not suit the concept of erosion control through better land husbandry supported by mechanical protection, and the division is artificial when we start talking about progressive terracing using grass strips or live hedges.

An approach more suited to today’s thinking is to group methods and techniques according to their main objective. All have an element of saving soil loss, but an important difference is the handling of surface runoff. This chapter identifies three kinds of water management objective and two types of soil management on sloping land.

5.1 Introduction
Since the early days of human interaction with the environment, particularly in industrial settings, humans have continually been “shaped” to meet the demands of their surroundings. Historically, people have often endured significant discomfort and limitations without much complaint. In metaphorical terms, individuals have adapted by extending their reach to operate controls that were difficult to access, pushing their perceptual abilities to detect faint sounds or invisible signals, and compressing their bodies to fit into cramped workspaces. Cognitive abilities have also been stretched to accommodate monotonous or tedious tasks. However, as both work environments and machines have grown more complex, these challenges have become increasingly significant. A poor “fit” between the human operator and their environment has led to countless accidents, decreased productivity, and errors in many industries. The primary goal of ergonomics is to assess human capabilities and design the environment to align with these capabilities. Instead of attempting to adapt humans to jobs, ergonomics strives to “fit the job to the person.” This approach aims to optimize safety, efficiency, and comfort by aligning machine requirements with the operator’s abilities. By establishing a connection between humans and machines, ergonomics ensures that machines communicate information to the operator through their sensory systems, prompting a response that may alter the machine’s state. Key environmental factors such as temperature, humidity, lighting, sound, and visual conditions have a direct impact on both human well-being and the quality of production. The design of both the human workspace and the equipment used can be highly effective if the environment is conducive to the operator’s needs. Therefore, it is essential to study each environmental factor from an ergonomic perspective to ensure a comfortable and productive environment for workers. This includes designing jobs, equipment, and considering human anthropometric measurements in the design process.
5.2 Heat
Heat stress occurs as a result of the combined effects of environmental conditions, physical exertion, and clothing. The key environmental factors influencing heat stress include air temperature, humidity, radiant heat, and air movement, all of which can significantly affect work performance. Heat strain refers to the

9. WEATHERING

The general process of production of rock waste partly by mechanical breaking and partly by chemical decomposition is known as weathering. The resulting products of weathering accumulate in the same place from which they are derived and there is no transport involved in the process.

Agents and types of weathering : The agencies which are involved in the process of weathering are atmosphere, water and organisms. The whole process of weathering may be conveniently divided into two types : mechanical or physical weathering and chemical weathering. Mechanical weathering involves those processes which bring about disintegration of rocks and minerals without any chemical activity. Chemical weathering involves various chemical processes which slowly decompose the rocks and minerals. In nature two processes are intimately associated and only under extreme conditions, they do occur as a separate entities. Mechanical weathering breaks down the rock creating more surface area and facilitates chemical weathering. Chemical weathering weakens the rock and makes it more susceptible to mechanical break down. Thus the two processes are always complementary to each other.

Defintion

Management of plant diseases using physical means is called physical management.

Also called physical therapy or thermotherapy.

It is mostly curative in nature.

PRINCIPLES

The principles involved in thermotherapy is that the pathogens present in seed material are inactivated or eliminated at temperatures nonlethal for the host tissues.The exact mechanism by which heat inactivates the pathogen is not fully understood. However, it is universally accepted that heat causes inactivation and not immobilization of the pathogen by heat. Thrate at which the pathogen is inactivated is determined by temperature, the higher the temperature, the faster is the inactivation.

Principles
The principles involved in thermotherapy is that the pathogens present in seed material are inactivated or eliminated at temperatures nonlethal for the host tissues.The exact mechanism by which heat inactivates the pathogen is not fully understood. However, it is universally accepted that heat causes inactivation and not immobilization of the pathogen by heat. Th rate at which the pathogen is inactivated is determined by temperature, the higher the temperature, the faster is the inactivation. At constant temperature, the drop in the density of pathogenic inoculum.
Methods
Following physical methods are employed for reduction or elimination of primary inoculums that may be present in seed, soil, or planting material.
i. Hot water treatment (HWT)
Hot water treatment is widely used for the control of seed borne pathogens, especially bacteria and viruses. A list of various important diseases claimed to have been controlled by hot water treatment is given in Table-1.

It is classified asbottom-up manufacturing which involves building up of the atomor molecular constituents asagainstthetop methodwhich involves making smaller and smaller structures through etching from the bulk material as exemplified by the semiconductor industry.