eChapters

Wind stress at the sea surface not only causes horizontal movement of water (Ekman Net transport), but also leads to vertical motion (Ekman Pumping). This horizontal movement of water leads to the occurrence of upwelling and down welling throughout the oceans both at coastal boundaries as well as in the open ocean. As divergence of surface water causes rising, convergence of the surface water causes sinking. This rising and sinking of water are called upwelling and down welling.

Harald Ulrik Sverdrup (1888-1957), a Norwegian who began his career studying meteorology with Vilhelm Bjerknes in Oslo, was appointed director of Scripps Oceanographic Institution in 1936. His 1947 paper “Wind-driven currents in a baroclinic ocean”, which showed the link between meridional currents and the curl of the wind stress, began the modern era of dynamical oceanography and initiated large-scale modeling of ocean circulation.

While circulation is a measure of tendency of fluid rotation, vorticity is the same property of fluid for an infinitely small area.

Sverdrup’s contribution could not take into account of the western boundary and so could not explain about the circulation what happened along the west coast of the ocean. Thus his circulation, as shown in Fig.8.1c in the chapter 8, is incomplete. This problem was solved by an American Oceanographer, Henry Stommel, in 1948.

Munk (1950) built upon Sverdrup’s theory, using both the vertical and lateral eddy viscosity. Munk combined the basic features contributed by Ekman, Sverdrup and Stommel to provide the first comprehensive solution of the wind driven circulation, using the real wind field Munk included the effect of eddy viscosity in both the horizontal and the vertical dimensions (both A_h and A_z).

As water consists of two positively charged hydrogen ions and a single negatively charged oxygen ion, water is arranged as a polar molecule having positive and negative sides. This molecular polarity leads to water’s high dielectric constant (ability to withstand or balance an electric field). Water is able to dissolve many substances because the polar water molecules align to shield each ion, resisting the recombination of the ions.

The wind blows over the water, changing its surface into ripples and then to waves. Thus most of the normal waves are wind-driven. As waves grow in height, the wind pushes them along faster and higher. Sometimes waves can become unexpectedly strong and destructive. As waves enter shallow water, they become taller and slow down, eventually break on the shore.

Small amplitude wave theory was based on the premise that motions are sufficiently small to allow the free surface boundary condition to be linearized. Finite amplitude wave theories or Stokes’ higher order theories are similar as per the concept in which additional higher order terms that were neglected in the Airy’s theory are included. In general, the higher the order of the wave theory, higher will be the limiting wave height for which it would be valid.

In order to understand the generation of tides first we should understand the motions of earth with respect to sun and moon. Tides are affected by the orbit of the moon around the earth and, less so, by the earth around the sun. The orbital motion of earth with respect to sun and the orbital motion of moon with respect to earth are as shown in Fig.15.1.

The word estuary is derived from the latin word ‘aestus’ meaning tide and the adjective ‘aestuarium’ means tidal. This means low ground covered by the sea at high water.

The world population is expected to reach 9 billion by 2050. This population growth of 2 to 3 billion people over the next 30 years, combined with the changing diets, would result in a predicted increase in food demand of around 70% by 2050 (UNDESA 2009).

Insecticides are one of the key control measures to combat the insect pests for sustainable agricultural production in the world. Synthetic insecticides have been only strategy to control the resurgent and resistant insect population in of high value crops not only in India but also in the world. The advent of synthetic insecticides in the mid-20th century made the control of insect and other arthropod pests easy and much more effective, and such chemicals remain essential in modern agriculture despite their environmental issues.

The biocontrol use had almost completely disappeared due to the growth and success of the synthetic pesticide industry in the mid-1940s. The publication of Rachael Carson's 'Silent Spring' (Carson 1962) which condemned the use of agricultural pesticides and emphasized their harmful environmental effects on wildlife. Due to public outrage over this controversial book, there was a need for pesticide alternatives, which presents an opportunity for wider use of biological control (Barratt et al. 2010; Gay 2012).

Three kinds of biocontrol products are being used in India which include 1) Microbial biopesticides, 2) Plant-derived botanical pesticides, and 3) Pheromones or other natural insect growth regulators. Microbial biopesticides consist majorly of fungi, bacteria, viruses or entomopathogenic nematodes as bioactive principles.

Biopesticides are pesticides that are produced naturally by plants, animals, microbes, and other minerals. These represent less of a harm to humans and the environment than chemical insecticides. Nanotechnology is a rapidly developing scientific topic that has numerous uses in numerous industries, including agriculture. The transport of plant hormones, seed germination, water management, transfer of target genes, nano barcoding, nano sensors, and controlled release of agrichemicals are now being investigated as applications for nanotechnology in agriculture (Worrall et al. 2018).

Insecticide based plant protection in India as well as in the world resulted in wide variety of environmental and health issues. Insecticides although gave satisfactory control of target pests initially, have posed serious issues such as resistance, resurgence and residue and also contamination of water bodies, food chain leading serious ill effects in humans, mammals, soil beneficial microbiota etc. After thorough examination of scientific evidences and facts on ill effects of synthetic organic insecticides, much emphasis was given for biological control including parasitoids, predators, entomopathogens, biopesticides, microbial control etc. in order to overcome above ill effects.

A tremendous change in the Indian biopesticide industry and market has reflected on increased global trade in agricultural commodities, a healthy revolution in the consumers and stack-holders with adequate understanding on negative effective of chemical pesticides in plant protection. Currently biopesticides comprise approximately 3-5% of the Indian pesticide market, with at least 15 microbial species and 970 microbial formulations registered through the Central Insecticides Board and Registration Committee (CIBRC).

Worldwide, various biopesticides have been created and are in use, including viruses, microorganisms (bacteria, fungi, etc.), microorganism derived products, animal derived goods (pheromones, hormones, insect-specific toxins, etc.), plant derived products, and genetically modified organisms (Nicholson 2007; Erlandson 2008; Mazhabi et al. 2011; Islam and Omar 2012).

The single piece of legislation under the Indian Government that regulates the import, manufacturing, sale, transportation, distribution, and use of all varieties of insecticides, including biopesticides, is the Insecticide Act (1968). Various parameters like shelf life, cross-contamination, moisture content, and packaging are significant factors that must be addressed before a biopesticide is registered. According to Organization for Economic Co-operation and Development’s (OECD) recommendations, CIB simplified the protocols and listed the infrastructure needs for manufacturing of biopesticides. Information required to generate toxicity calls a strenuous effort.

Pest and pathogen incidence is a natural occurrence that frequently goes unreported. However, they become a concern when their spectra expand and cause significant losses. Chemical pesticides are now commonly used in agricultural techniques to lessen the impact of such severe damages. Without a question, the use of chemical pesticides has put human health, ecological health, and sustainability at danger.

Regulations should make it easier to utilise creative, long-lasting solutions, allowing for the selection of the most environmentally friendly pest management method. This can be accomplished by using expedited registration, priority registration, and a combination of comparative evaluation of pest control techniques and the substitution principle, which allows a natural pest control technique to take the place of a synthetic pesticide.

Accidental sampling: Accidental sampling as quota sampling is based upon the convenience in accessing sampling population. While quota sampling attempts comprise people possessing an obvious/visible characteristic, accidental sampling makes no such effort. Any person that comes across can be contacted for participation in the study. Collecting data are stopped when reaching the required number of respondents decided to have in the sample.

Bar chart: The bar chart or diagram is one of the ways of graphically displaying categorical data. A bar chart is identical to a histogram, except that in a bar chart the rectangles representing the various frequencies are spaced, thus indicating that the data is categorical. The bar diagram is used for variables measured on nominal or ordinal scales.

Canonical analysis: The canonical analysis can be used in the case when both measurable and non-measurable variables for the purpose of simultaneously predicting a set of dependent variables from their joint covariance with a set of independent variables.

Data Analysis: In the process of data analysis, connections or differences supporting or clashing with unique or new hypotheses should be subjected to statistical tests of significance to decide to what validity data can be said to show any conclusions.

Economy consideration: Economy consideration suggests that some tradeoff which is needed between the ideal research project and that which the budget can afford. The length of measuring tool is an important area where economic pressures are quickly felt. Even though more items give superior reliability, but in the interest of limiting the interview or observation time, the research worker is to take only a few items for his study purpose.

Factor analysis: Factor analysis is the most commonly employed multivariate procedure in the research studies when there is a systematic interdependence among a set of observed or manifest variables and the research worker is interested in finding out something more fundamental or latent which creates this commonality.

General article: A general or popular article is like a short review paper based on an area of public interest. The author can incorporate his own idea on the particular topic in this article.

Halo effect: When making an observation, some observers may be influenced to rate an individual on one aspect of the interaction by the way he was rated on another. This is similar to something that can happen in teaching when a teacher’s assessment of the performance of a student in one subject may influence his rating of that student’s performance in another.

Illuminative evaluation: The primary concern of illuminative or holistic evaluation is a description and interpretation rather than measurement and prediction of the totality of a phenomenon. It fits with the social–anthropological paradigm. The aim is to study a programme in all its aspects: how it operates, how it is influenced by various contexts, how it is applied, how those directly involved view its strengths and weaknesses, and what the experiences are of those who are affected by it.

Judgment sampling: Judgment sampling is utilized frequently during qualitative research to develop hypotheses rather than to generalize to larger populations. The research worker’s decision is used for selecting items which are considered as representative of the population in judgment sampling.

Karl Pearson’s coefficient: Karl Pearson’s coefficient of correlation (also simple correlation) is the most widely used methods of measuring the degree of relationship between two variables. This coefficient assumes that there is a linear relationship between the two variables; the two variables are causally related which means that one of the variables is independent and the other one is dependent; and a large number of independent causes are operating in both variables so as to produce a normal distribution.

Latent Structure Analysis: Latent Structure Analysis shares both of the objectives of factor analysis to extract latent factors as well as an express relationship of observed (manifest) variables with the factors as their indicators and to classify a population of respondents into guanine types. This analysis is suitable if the variables involved in the study do not possess dependency relationship and happen to be non-metric.

Matching: The matching is a technique that is used to form two groups of subjects to set up an experiment–control study to test the effectiveness of a treatment. From a pool of subjects, two subjects with identical predetermined attributes, characteristics or conditions are matched and then randomly placed in either the experimental or control group.

Narratives: The narrative technique of gathering information has even less structure than the focus group. Narratives have almost no predetermined contents except that the research worker seeks to hear the personal experience of a person with an incident or happening in his life. Essentially, the person tells his story about an incident or situation and the research worker, listen passively, occasionally encouraging the respondent.

Objective- oriented evaluation: The objective- oriented evaluation is the evaluation when it is designed to ascertain whether or not a programme or a service is achieving its objectives or goals.

P.C. Method of factor analysis: Principal-component’s method or simply P.C. Method of factor analysis, was developed by Hotelling. This \method searches to maximize the sum of squared loadings of each factor extracted. Accordingly P.C. factor determines more variance than would the loadings obtained from any other method of factoring.

Qualitative approach to research: Qualitative approach to research is concerned with subjective assessment of attitudes, opinions and behaviour. This type of approach to research generates findings either in non-quantitative form or in the form which are not concerned with the rigorous quantitative analysis. Commonly, the techniques of focus group interviews, projective techniques, and depth interviews are used.

Random design: In a random design, the study population groups as well as the experimental treatments are not predetermined, but randomly assigned to become controlling or experimental groups. Random assignment in experiments means that any individual or unit of the study, the population has an equal and independent chance of becoming a part of the experimental or control group or, in the case of multiple treatment modalities; any treatment has an equal and independent chance of being assigned to any of the population
groups.

Sample: A sample is a subgroup of the population, which is the focus of research inquiry and is selected in such a way that it represents the study population. A sample is composed of a few individuals from whom the required information is collected. It is done to save time, money and other resources.

Table of random numbers: Most books on research methodology and statistics have tables that contain randomly generated numbers. There is a specific way of selecting a random sample using these tables.

Uncontrolled observation: Uncontrolled observation is the observation when it takes place in the natural setting and the situations cannot be controlled by the research worker.
Unethical: Any professional activity that is not in accordance with the acceptedcode of conduct for that profession is considered unethical.

Validity: The concept of validity can be applied to every aspect of the research  process. In its simplest form, validity refers to the appropriateness of each step in finding out what is set out to. However, the concept of validity is more associated with measurement procedures.

Wilcoxon Matched-pairs Test: The Wilcoxon Matched-pairs Test can be used if the research situations where two-related samples, i.e. case of matched pairs such as a study where husband and wife, or the output of two similar machines or some subjects are studied in context of before-after experiment, the magnitude of difference between matched values in both the directions are to be determined.

χ^2-test: The χ² test (chi square test) is based on the assumption of normality. The χ^2-test is based on chi-square distribution and as a non-parametric test, it is used for comparing a sample variance to a theoretical population variance.

Yates’ correction: Yates has suggested a correction for continuity in χ² value calculated in a 2×2 table, predominantly when cell frequencies are small and χ² is just on the significance level. The correction suggested is known as Yates’ correction, which involves the reduction of the deviation of observed from expected frequencies that reduces the value of χ².

z-test: The z-test is based on the assumption of normality. The z-test is based on the normal probability distribution and is used for judging the significance of several statistical measures, particularly the men.

Mentzer et al. (2001) defined SCM as ‘the systematic, strategic coordination of the traditional business functions within a particular organization and across businesses within the supply chain, for the purposes of improving the long-term performance of the individual companies and the supply chain as a whole’. According to Walters and Lancaster (2000), supply chain management is the management of the interface relationships among key stakeholders and business functions that occur in the maximization of value creation which is driven by customer needs satisfaction and facilitated by efficient logistics management.

An agriculture supply chain system comprises organizations/cooperatives that are responsible for the production and distribution of vegetable/Fruits/Cereals/ Pulses or animal-based products. In general, we distinguish two main types:

‘Agriculture food supply chains for fresh agricultural products’ (such as fresh vegetables, flowers, fruit). In general, these chains may comprise growers, auctions, wholesalers, importers and exporters, retailers and speciality shops and their input and service suppliers. Basically, all of these stages leave the intrinsic characteristics of the product grown or produced untouched. The main processes are the handling, conditioned storing, packing, transportation and especially trading of these goods.

Agricultural policies in the past have witnessed a series of iterative changes following the economic reforms during the 1990s that marked a Division of Agricultural Economics. Though many of the reform processes were not initiated to directly affect the agriculture sector, it was affected indirectly (Chand, 2004). The mounting stock of food grains has partly been due to the weak purchasing power of the poor in the country. Nevertheless, the problem associated with buffer stock management and degradation of natural resources in some regions has triggered a debate to redefine the agricultural policies. As a remedial measure, it has been suggested that India should diversify its agriculture and get a foothold in the world market (Radhakrishna and Reddy, 2004).