eChapters

ABSTRACT

India is blessed with large reserves of strategic and economically important heavy minerals such as ilmenite, rutile, leucoxene, zircon, monazite, garnet and sillimanite. These deposits are mostly located in the coastal stretches of Peninsular India especially between the high tide line and 200-250m inland, with the exception of few inland deposits. Ilmenite is the largest constituent of the Indian beach sand deposits, followed by sillimanite and garnet. These minerals are one of the largest and higher grades in the World. The Indian Ilmenite resource base totals 348 million tones (Mt), along with 18 Mt of rutile, 21 Mt of zircon, 8 Mt of Monazite, 107 Mt of garnet and 107 Mt of sillimanite. Although Indian heavy mineral resources are one of the largest in the world, it is observed that the Production to Reserve Ratio (PRR) is a meager 0.0013; that is insignificant compared to other countries with similar resources.

Abstract

The Remote Sensing and the followed up field based investigations show that the Tamil Nadu coast, India, is facing series of geoenvironmental problems due to tectonic movements and morphodynamic processes. Such problems pose a challenge to the engineering geologists. The paper discusses such challenging engineering geological problems and plausible remedial measures.

ABSTRACT

Sedimentological studies such as textural, heavy mineral and clay mineralogy have been carried out for Warkalli Formations at Varkala, situated in the southern part of Kerala, India. The X-ray diffraction study reveals that kaolinite is the only clay mineral present in all the samples with trace amounts of gibbsite and goethite. The higher amount of kaolinite and gibbsite indicates warm and humid paleoclimatic conditions. The textural analysis shows that the sediments are moderate to poorly sorted, nearly symmetrical to fine skewed and lepto to mesokurtic in nature. A plot of skewness against sorting shows fluvial trend. The major heavy minerals present in the samples are magnetite, ilmenite, rutile, sillimanite, anatase and zircon. It can be inferred from these studies that these sediments would have been deposited in a lagoon by fluvial action. During that time, the source region has experienced tropical humid climate with mean annual precipitation (MAP) above 200 cm and intensive chemical weathering. Heavy mineral assemblage indicates medium to high grade metamorphic source rocks.

Aristotle (384 to 322 BC), an ancient Greek philosopher and scientist (Fig. 1.1) developed the concept of meteorology as a study of the lower atmosphere. Over the years meteorology developed as a science of atmosphere which deals with the physics, dynamics and chemistry of the atmosphere and their effect upon the earth’s surface, oceans and thereby life in general either directly or indirectly.

As the atmospheric conditions change from time to time in a given area and from place to place in a given time, climatology was developed as a science which studies the average conditions of the weather and its variability over a long period of time.

All most all the human activities are greatly influenced by the weather and climate to a greater extent. Therefore, the scope of meteorology encompasses various activities which are of considerable economic significance as detailed here below;

1.1 Housing

The design and construction of houses, buildings, industrial structures etc. depends upon the weather and climate of the region. Orientation of doors, windows roofs of the buildings are usually designed to provide maximum comfort and convenience to the people.

Introduction

Agriculture has historically been the primary source of income in India. It has the potential to alleviate poverty, increase income, and enhances food security for 80% of both the world’s poor and people who reside in rural areas primarily work in agriculture. One of the most effective strategies to eradicate extreme poverty, increase shared prosperity, and feed an estimated 9.7 billion people by 2050 is agricultural development. Compared to other modes, the agro - based sector’s progress is two to four times more successful in enhancing the earnings of the poorest people (www.worldbank.org).

Nearly 5 billion hectares, or 38% of the world’s land surface, is used for agriculture. Around one of this is devoted for farming, and the remaining two thirds are pastures and meadows for grazing animals. Over 10% of cropland is assigned to permanent crops like cocoa plantations, oil palm plantations, and fruit tree orchards. Yet another 21% of land is primed for irrigation, a crucial agricultural land management technique.

Introduction

India has one of the world’s largest agricultural production areas of land. The net sown area is 140.1 million hectares, the net irrigated area is 49% of this, which is 68.4 million ha as per 2014–15 land-use statistics (Agriculture Research Data Book 2019). While the proportion of Indians employed in agriculture is decreasing, agriculture, along with its allied sectors such as livestock, forestry and fisheries, remains India’s primary source of income. As per the Lok Sabha Standing Committee on Agriculture (2019–20), agriculture and allied industries employed 54.6 percent of India’s total workforce. Approximately 70% of rural households still rely primarily on agriculture for a living. Agriculture and allied sectors’ share of the country’s Gross Value Added (the value of goods and services produced in an area, industry, or sector of an economy) has fallen from 18.2 percent in 2014-15 to 16.5 percent in 2019-20. As per current trends, 60% of India’s population (more than 10% of the world’s population) will face severe food shortages by 2050.

Clouds play very important role on weather and climate. The formation of clouds takes place when water condenses in the sky. Clouds are visible accumulation of tiny water droplets and ice crystals in the Earth’s atmosphere. The moisture is always present in the atmosphere though it may not be visible. Clouds form when air becomes cooler until the water vapour present in it condenses to liquid form. The condensation over oceans occurs around solid particles like salt, dust, smoke etc. suspended in the atmosphere. The type of clouds depends upon temperature and wind. The clouds are classified based on physical appearance and the height at which clouds are formed (Fig. 7.1).

ABSTRACT

The geological and geomorphological features could be clearly demarcated in and around Salem area using IRS -IB LISS II satellite data. Geologically,the study area is classified into four major rock types fissile hornblende biotite gneiss, banded magnetite quartzites, peninsular gneiss, charnockites and quartzites. The geomorphological study reveals the buried pediments medium, buried pediments deep, bazada zone, along with lineaments. Intersections of the lineaments are the most prospective zones for further groundwater targeting. Shallow pediments and pediments are the less groundwater prospective zones. But detailed geophysical survey as required to sink new bore well, dug well, dug cum bore wells.

33. GEOTECTONICS

Introduction

Geotectonics is the branch of geology which deals with the structure and movements of the earth’s crust. It includes the study of large-scale features like mountain chains, mid-oceanic ridge and oceanic trenches. Investigation regarding the form, pattern and genesis of these, and other tectonic units have enabled geo-scientists to ascertain the important characteristics of earth’s crust and reconstructs its evolution and geological history.

ABSTRACT

The present paper discusses about the Geoelectrical response over Charnockite rocks and Biotite Gneiss rock types of Sankaran kovil and Tenkasi Taluks of Tirunelveli District, Tamilnadu. The study area is adjoined to the Western Ghats which geologically comprises Archean crystalline hard rocks. In this attempt, about 7 Vertical Electrical Soundings (3 in Gneiss and 4 in Charnockite) have been carried out in both terrains. The VES values were interpreted with Schlumberger Sounding Dada Processing and Interpretation Program .The resistivity values varied from 68 m to 808 m with the layer thickness of 10m, 20 m and 29m in the biotite gneiss terrain. Similarly, the resistivity values varied from 48 m to 444 m with the layer thickness of 4m, 6m, 9m,18m & 29m in the charnockite terrain. But the depth to massive rock for both the rock types has been observed below 29m. In this study, a difference in resistivity with high resistivity values in gneissic terrain and lower values in charnockite terrain have been observed. The observed resistivity differences are mainly due to the presence of resisting minerals such as biotite and hornblende. Besides, other factors like weathering and water table also influence the resistivity values. Hence, it is summerised that the geoelectric methods are the best methods to understand the subsurface lithostudies.

33. GEOTECTONICS

Introduction

Geotectonics is the branch of geology which deals with the structure and movements of the earth’s crust. It includes the study of large-scale features like mountain chains, mid-oceanic ridge and oceanic trenches. Investigation regarding the form, pattern and genesis of these, and other tectonic units have enabled geo-scientists to ascertain the important characteristics of earth’s crust and reconstructs its evolution and geological history.

1.0 Overview

Natural resources sustain life and are critical for economic development of nations. In developing countries like India where more than half the population is rural, economic development is inextricably linked with agricultural development. In these countries, the food and livelihoods security of the poor are critically associated with access to the services provided by the natural resources - land, soil, water, biodiversity and climate resources. The natural resources are finite, and with increasing population, economic growth, urbanization, and demands for food and other agricultural commodities, these are being increasingly strained. As a result, the productive capacity of the natural resource base is shrinking and deteriorating. Sustaining the productive capacity of natural resources for future generations, while meeting the food and other demands of the growing populations, is the major development challenge of the twenty first century.

In India, during the last forty years the net sown area under agriculture has remained nearly constant at 141 million ha. In the same period, the population has more than doubled (from 541 million in 1970 to 1186 million in 2010) and per capita income grew by more than 3.5 times (from Rs 14824 in 1970 to Rs 53331 in 2010). As available land resources for agriculture are finite, increases in agricultural production to meet the growing demands of the population have to come from intensification of agriculture on the same lands. As a result, the quality of soils on these lands is gradually deteriorating both at the farm and ecosystem levels. The major threats to soil quality come from loss of organic carbon, erosion, nutrient imbalance, compaction, salinization, water-logging, decline in soil bio-diversity, urbanization, and contamination with heavy metals. More than 100 million ha of the total cultivated land of 141 million ha is stated to be under some form of soil degradation.

Similarly, utilizable fresh water resources of India are finite at about 1123 billion cubic meters (BSM), of which about 690 BCM are from surface water resources and 433 BCM are from groundwater. This supply is shared among multiple uses: human and animal consumption, agriculture, urban uses, industry and for provision of environmental services. The total water demand in 2010 is estimated at 710 BCM and is projected to increase to 1180 BCM by 2050. Several parts of India are already facing severe water shortages as a result of the growing demand for water. The quality of water resources is also impacted by agricultural intensification and development, and is increasingly a matter of concern. By the year 2050, when population is expected to stabilize, the shortages will only intensify. The country as whole can be on the verge of becoming a water scarce country, with nearly all the presently estimated utilizable water resources being put to use.

Biodiversity natural resources refer to the abundance of different species and ecosystems in nature. These resources are the primary sources of present and future productive agriculture and human well being, as they provide the basic resources for use in breeding crops and livestock, soil formation and structure, soil fertility, nutrient cycling and the provision of water services. India is among the 12 mega diversity regions of the world. It is known to have more than 18,000 species of higher plants including, 160 major and minor crop species and 325 of their wild relatives. Increasing pressure from human population growth, agricultural intensification, urbanization, pollution and degradation of land, soil and water resources are having a negative impact on the plant, animal and microbial biodiversity resources of the country and their productivity.

Abstract

Soil Resource Appraisal helps in characterizing the existing land resources, assessing their suitability for various land uses and then helping the user to prepare a rational land use plan suitable for the integrated development of the area. Application of Remote Sensing (RS) and Geographical Information System (GIS) helps not only in the characterization of the resource base, but also in the generation of various thematic maps and preparation of land use and action plans for effective implementation of various developmental plans at farm level.

Keywords : Soil Resource Appraisal, Land Use Plan, Farm level Developmental Plans

1.0 Introduction

A thorough knowledge and understanding of soils is basic to the development and management of agricultural resources. About 100 years ago, man began systematic study of soils in the field and tried to separate, classify and map their geographic distri­bution. Today we have sufficient knowledge about soils; however the characterisation, classification and mapping of soils is still tedious, time consuming and costly affair. Therefore the need for adopting new and more rapid and accurate methods of mapping soils has resulted in the use of satellite images with image interpretation techniques for soil survey and map­ping.

In India for the country as a whole, soil and other land resources information is available at 1:1 M scale, which was generated from the state level mapping done at 1:250,000 scale under the Soil Resources Mapping Project of India during the period from 1986 to 1995. This information is of general nature and useful for planning on a wide canvas and not particularly useful for farm or watershed level planning in the country. For site-specific needs and for developmental works at watershed level, we need detailed farm level database at 1:10,000 scale. Once this type of information is generated at village/watershed level, this will be useful for identifying site specific constraints, generation of area and site specific agro technologies, land-use options based on soil site suitability assessment, wasteland identification, identification of prime farm lands and farm clusters for zoning and Strategic planning, preparation of farm level development plans by line departments and proactive advice and technology transfer to farmers.

Abstract

Remote sensing is the art and science of obtaining information about an object or phenomenon without having any contact with the object concerned. Geographical information system is a tool to create, manage, retrieve and query spatial databases. Remote sensing in conjunction with Geographical Information System (GIS) has wide applications in all spheres of life and especially in agriculture. Specifically, this paper reveals some of the applications of remote sensing and GIS in the field of crop condition assessment viz., crop type classification, crop stress detection, crop yield estimation and pest and disease monitoring.

Keywords : Remote Sensing, GIS, Yield Forecasting, Crop Stress, Pest and Disease Monitoring

1.0 Introduction

Remote sensing is the art and science of obtaining information about an object or phenomenon without there being any physical contact. The information is so collected using a device called a sensor. The sensors are mounted on a platform at an advantageous position. Accordingly the remote sensing is called ground based (sensor is hand held or mounted on mast), air borne (sensor is on a balloon or aero plane) or space borne (sensor is mounted on a satellite). The basic principle in remote sensing is that each and every object has unique reflecting property like human thumb impression and when the solar energy is falling on an object a part of it gets reflected, which carries the information about the object. The reflected light is converted in to reflection percentage of incoming solar radiation. This percentage of reflection can be used to work out the vegetation indices which are surrogate measure of crop condition.

Geographical Information System (GIS) is software system which enable Collection of large volume of data with spatial relation Integration of data from different source is possible Analyze such data for our requirement Present the data in different formats (maps, table and reports)

Introduction

Canopy management is defined as managing plant architectural design as per need, using their inherent characteristics which is in accordance with a given set of conditions and resources to perform the plant maximum (Nath et al, 2014).The modern principles of sustainable fruit production systems focused on optimal use of natural resources (light, water, soil fertility) where the input (labour, energy, fuel, other material) and output (yield) are well balanced and the resources remain renewable.

Fruit orchards can be considered as artificial ecosystems converting the energy of photosynthetic active radiation (PAR) into edible, marketable fruits for human consumption. The core of this system is the bio-factory of leaves driven by the absorbed PAR. Several data support that the light interception is the basic factor for the modern orchard systems. Factors as LAI (Leaf area index), tree spacing, training and pruning systems, fruiting wood development, rootstocks and genotypes also have an important bearing on orchard efficiency.

The main objectives of canopy architecture is to develop strong tree framework, maximize utilization of light, accommodate more number of trees per unit area, maintenance of tree orchard uniformity and induce and sustain proper amount of well distributed fruiting terminals.

In order for the fruit production system to remain sustainable, the orchard system should favour the contributory role of an input of natural origin to the maximum possible extent, in improving the yield in the early years and provide high yields after the trees are mature until the planned age of the orchard. Recent development in the tree architecture has produced some promising tree training and pruning systems as well for high density fruit orchards.

ABSTRACT

Identification and mapping of fractures/lineaments and hydrogeomorphic units is prerequisite for undertaking ground water exploration and development in any terrain. Remote sensing and GIS techniques have been used for ground water potential mapping in Theni District. The study area has been divided into various geomorphic units based on visual interpretation of LISS III and PAN merged data in false colour composite on 1:50,000 scale. Ground water potential of each of the geomorphic units was assessed and correlated with geology, structure and recharge factors prevailing in the Theni District.

Introduction

We are blessed with solar energy in abundance at no cost. The solar radiation incident on the surface of the earth can be conveniently utilized for the benefit of human society. Solar energy can be used as thermal energy for water heating, cooking, drying, distillation, space heating, cooling and power generation or it can be converted to electricity through photovoltaic cells, commonly known as solar cells. One of the popular devices that harness the solar energy is solar hot water system (SHWS). Flat plate collectors are used for low temperature applications (below 100^oC) while concentrators are preferred for higher temperatures. The most efficient application of flat plate collector is for getting hot water. Hot water in winter is an essential requirement for domestic uses such as bathing, cleaning of utensils and washing of clothes. In rural areas hot water is also required for softening of animal feed. Generally it is obtained by using firewood and cow dung cake in rural areas or using kerosene, liquid petroleum gas, coal or electricity in urban areas. Therefore, the use of solar water heaters will conserve lot of commercial and non-commercial fuels which are being wasted in merely getting hot water. A solar water heating system (SWHS) is made of several important elements: one or more solar collectors, a pump, a heat exchanger, a storage tank (or multiple tanks) and a back-up storage tank. The Solar heating system can be classified as passive or active. For water heating purposes, the general practice is to use flat plate solar energy collectors (FPC). The evacuated tube collectors (ETC) and evacuated tube heat pipe collectors (ETHP) are more efficient, though, the initial cost is comparatively higher. There are three type of water heaters extensively studied by various workers viz. natural circulation, collector-cum-storage and forced circulation in all over the world.