eChapters

African agriculture is in crisis, and Africa’s farmland is losing its fertility at an alarming rate. Farmers grow the same crops in the same fields year. They don’t fertilize, and they don’t terrace their fields. When the soil wears out, the clear a new piece of land (wwww.npr.org). N. Kozana Diamini Luma, the Chairperson of the African Union Commission has emphasized that ‘the year 2014 – the year of Agriculture in Africa’ will be used as an opportunity to accelerate the drive for food security. The major thrust for that has to be on ensuring that the farmers make their profession on economic activity that generate wellbeing for all in a sustainable manner (1, 2).

Large quantities of crop residues are produced and if properly used, they can provide cost effective means for supplying organic matter, plant nutrients and improved soil health. The highly lignocellulosic nature of crop residues indicate their potential role in maintaining soil organic matter and enriching the soils with N-rich microbial biomass resulting from decompositions. However, their indiscriminate handling often burning leads to decline in soil health, air pollution and overall loss. Since most crop residues find use as feed and fuel, efficient recycling of the remaining amount can have very significant and positive effect.

Abstract

The arid Kachchh district, located at the western most part of the Gujarat State in India, is known for its large extent of area under wetland habitat, which is represented by numerous seasonal water bodies and coastal habitats. Vast stretch of grasslands also available in the northern border of the district, the Banni (23⁰ 19’ to 23⁰ 52’ N; 68⁰ 56’ to 70⁰ 32’ E), which encompasses an area of 2,617 km². There are many depressions in Banni, locally known as Dhandh (shallow lakes). During monsoon, rainwater gets collected in these depressions and form shallow lakes. About 34 smaller and bigger size Dhandhs are present in the Banni. Banni communities are highly dependent on the Dhandhs for various purposes. Due to the erratic rainfall in arid Kachchh, Maldharis is highly unstable for livestock in search of fodder and water during drought years. During the normal rainfall years, livestock from neighboring talukas of Kachhh and even from other districts depends on this grassland and Dhandhs. During last decade, the Banni grasslands have seen serious environmental changes due to the invasion of an exotic plant Prosopis juliflora and increasing the salinity are the major issues of Dhandh degradation. Thus, the Banni is gradually losing its capacity to sustain human and livestock population.

Main objectives of the present paper is to examine the local perceptions of wetland and grassland change, socio-economic status, and factors that cause degradation of the wetland and vegetation resources in the Banni grassland.

The recent earthquake in Nepal brings back memories of 26th January 2001. While the nation was busy in celebrating Republic Day, an earthquake shattered Gujarat especially Kutch and Saurashtra regions. A large number of buildings and houses collapsed within moments. Thousands were injured and many lost their lives and many more became homeless.

Kutch received quick responses from all over the world and a large number of individuals, institutions, government and semi-government bodies, professional experts, religious and social organizations etc. sprang into action to bring back some normalcy in the lives. However, long-term rehabilitation program based on scientific planning is most vital after such disasters.

All agriculture universities have three main Directorates – Education, Research and Extension. Of the three, I have often observed that Extension Department comes in for maximum criticism. ‘Loose links’and ‘need to do much more in transfer of knowledge and technology’ are frequently emphasized at various levels – especially in meetings with farmers groups.

This is understandable – as it is said that less than 10% - often less than 6%, of lab scale knowledge and development reach the farmers fields in developing countries and even in many ‘developed’ counties. The situation is much more challenging when we consider a large population of small and marginal farmers – who as we saw can play extremely important role in eco-agriculture. A large percent of such farmers – women and men are practicing eco friendlyagriculture without realizing it. Their ‘ignorance’ can be converted in to advantage and new opportunity. The age old extension practice of reaching farmers through meetings, visit , seminars, camps, demonstrations all have limitations and need to be ‘scaled up’. New developments in information and communication Technology offer a great opportunity for a big jump in reaching the unreached. Again to alarge population of ‘Green Revolution’ – there is a new hope and opportunity.

Abstract

Three seepage tests were carried out for an earth canal at Rawakeeb Research Station (RRS)-west of Omdurman and an average seepage rate of 3.4 m/day was obtained. This value suggests that irrigation canal at RRS should be lined. In addition to that preliminary economic evaluation showed that canal lining is imperative in RRS. A concrete slab form was well designed for lining of RRS canal. Precasting technique and construction technique provided the required water tightness. Economic evaluation was done for RRS canal to investigate the extent of occurrence of supposed advantages, and to estimate costs and benefits and rate of return to lining. The capital expenditure (C), net present worth (NPW) and benefit/cost ratio were found to be 2600.4, 1961.9 and 1.3 respectively which offers a good indicator to adopt the technique.

7.1 Introduction

Energy has become a critical input for the economic development of the India because of the wide spread scarcity of oil and electricity and other commercial form of energy.

The rural areas are often the worst affected because of these shortages and the rural population continues to depend on the inefficient non-commercial energy from like fire wood, cow dung, human and animal for meeting their energy requirement for subsistence, production and devolvement needs.

The rural energy crises or “The energy crisis” has been getting increased attention from the policy makers to tackle the problem in a planned and integrated manner.

The rural energy sector is concerned with two major planning issues.

1. Provision of energy for meeting substance needs for cooking, heating and lighting of the rural areas of the country. This problem is also directly linked to the problem of deforestation and environmental destruction being caused in the rural area because of indiscriminate and wide spread use of non conventional energy sources.
2. Meeting energy requirements for production activities which would create employment and productivity in rural areas.

Solid wastes are all the wastes arising from human and animal activities, that are normally solid and that are discarded as useless or unwanted materials. It consists of the highly heterogeneous mass of discarded materials from the urban community as well as the more homogenous accumulation of agricultural, industrial and mining waste.

3.1 What is environment ?

The word environment is derived from a French word “environne” means to encircle or surround. Environment is defined as the circumstances or conditions that surround an organism or group of organisms. It is also defined as the complex of social or cultural conditions that affect an individual or community. Since humans inhabit the natural world and they build social, cultural and technological world, all constitute important parts of our environment.

7.1 What is Pollution?
 
Pollution is a contamination of the environment by man-made substances or energy that has adverse effects on living or non-living matter. In simple terms, pollution can be seen as the wrong substance in the wrong place in the wrong quantities at the wrong time. This implies that harm is caused to the environment if the same substance is present at levels too low.

Types of pollution
Pollution can be categorized according to the medium in which it occurs such as

El Nino is the name given to the occasional development of warm ocean surface waters along the coast of Ecuador and Peru. When this warming occurs the usual upwelling of cold, nutrient rich deep ocean water is significantly reduced. El Nino normally occurs around Christmas and lasts usually for a few weeks to a few months. Sometimes an extremely warm event can develop that lasts for much longer time periods. In the 1990s, strong El Ninos developed in 1991 and lasted until 1995, and from fall 1997 to spring 1998.

Water is indispensable for our life. About 2/3 of earth is covered with water. No organism can survive without water. So keeping water free from any pollutant is very important. Water is said to be  “polluted” when it is hanged in its quality and composition directly or indirectly by man’s activity so that it becomes less suitable for drinking, domestic, agricultural or any other purpose. Polluted water transmits a large number of diseases in man. They are cholera, typhoid, dysentery, jaundice and other bacterial or viral diseases.  Water becomes polluted by the presence or addition on inorganic or organic substances or biological agents. Soil erosion, leaching of minerals from rocks, decaying of organic matter are natural sources of water pollution. There has been an alarming increase in the degradation of water quality in the recent past in the large cities and industrial areas.

Water pollution can be studied under the following heads—  (i) medium in which it occurs (surface water, ground water); (ii) habitat (lakes, estuaries and open seas); and (iii) type of pollutants (bacterial, metallic, thermal and radioactive).

For the hundreds of thousands of years that we lived on earth,there were few rapid changes in the atmosphere. It is only in recent times, particularly since the Industrial Revolution, that our activities on earth began to modify our environment in a significant manner.  Industrial pollution has affected the water we drink, the air we breathe, and in general,the biosphere itself.Now noise has joined the bandwagon of pollutants.

Noise certainly comes within the scope of definition of a pollutant that “..... any undesirable change in the physical, chemical or biological characteristics of our air, land and water that may or will harmfully affect human life or that of any other desirable species or industrial process, living conditions or cultural assets, or that may or will waste or deteriorate our raw material resources.”

For electromagnetic radiation, there are four “laws” that describe the type and amount of energy being emitted by an object. In the following sections, these four laws of radiation e.g. Planck’s law, Wien’s displacement law, Steffan-Boltzman law and Kirchhoff’s law are described briefly.

Planck’s Law

Planck’s law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature T. The spectral radiance of a body, B_í, describes the amount of energy it gives off as radiation of different frequencies. It is measured in terms of the power emitted per unit area of the body, per unit solid angle that the radiation is measured over, per unit frequency. Planck showed that the spectral radiance of a body at absolute temperature T is given by

Introduction

Solar energy could be converted to electricity both through thermal route and photovoltaic cells but the latter is more advantageous as it has no moving part, it doesn’t require water, a rare commodity specifically in arid regions. Moreover, the maintenance of PV systems is easy, it can be installed right at the place of utility, the system is modular and these are reliable having life more than twenty years and of course eco-friendly.

In photovoltaic cells, generally known as solar cells, charge carriers are generated by the incoming irradiance (energy greater than band gap) and these are separated and swept away by an internal electric field, which is created by either making metal semiconductors contact (Schottky barrier) or p-n junction or MIS (Metal Insulator Semiconductor) or SIS (Semiconductor Insulator Semiconductor) devices. The height of potential barrier at the junction determines the voltage and the flowing charge carriers contribute to the current when connected externally. The choice of material depends on its band gap, absorption coefficient, diffusion length, mobility of charge carriers, ease in contact formation, type of junction with thermal and electronic compatibility, availability of material, toxicity and several other fabricational opto-electronic and practical aspects. PV cells based on single crystal and polycrystalline silicon, amorphous silicon, CdS, CdTe, CuInGaSe, InP, GaAs etc. have been much studied. PV modules of efficiency above 16% on silicon and 10% on CdTe, CuInGaSe and 8-9 % on amorphous silicon are commercially available. Dye sensitized TiO₂ devices have also been receiving more attention with coloured panels for windows. Organic semiconductors are explored and more recently perovskite solar cell has been studied. Flexible solar cell panels based on thin film devices are in use. The applications have gone from solar lighting to operation of pumps, small and medium size equipment, stand alone and grid connected solar power plants, roof top and building integrated PV and now even energizing cars and aero planes. With technological advancement and enhanced production (233 GW in 2015) the cost of commercially available PV modules, which used to be high at one time has been brought down from 30 $/Wp in seventies to about $0.5/Wp at present.

A biomass gasifier is an advanced device designed to convert solid biomass materials-such as wood chips, crop residues, saw-dust, coconut shells, and other organic matter-into a combustible gas mixture known as producer gas. The conversion process, known as gasification, is a thermo-chemical process that takes place in a controlled environment with limited oxygen. Unlike complete combustion, gasification allows only partial oxidation of biomass, producing a gas rich in carbon monoxide (CO), hydrogen (H2), methane (CH4), and nitrogen (N2). This gas mixture can be used as a fuel for internal combustion engines, power generation, cooking, or industrial heating applications.
Principle of Gasification
Gasification involves a sequence of four key thermo-chemical reactions within the reactor, occurring at temperatures ranging from 800–1000°C:
1. Drying Zone: Moisture present in the biomass is evaporated due to the rising heat.
H2O (liquid) ? H2O (vapor)
2. Pyrolysis Zone: Biomass decomposes in the absence of oxygen to form volatile gases, tar, and solid char.
Biomass ? Char + Volatile gases + Tar
3. Oxidation Zone: A small amount of air or oxygen is introduced to partially combust the biomass, generating heat to sustain the process.

Introduction
There are always going to be natural disasters like cyclones, earthquakes, and floods. They are a component of our surroundings. Nonetheless, the amount of damage caused by natural disasters can be reduced if there is a reliable warning system in place
and the impacted population is ready. Thus, while reactive mechanisms constituted the majority of disaster management in the past, a change towards a more proactive, mitigation-based strategy has been gradually observed in the last several years.
The field of emergency and disaster management focuses on mitigating and preventing potential hazards. It is a field that deals with anticipating catastrophes, responding to them (e.g., emergency evacuation, quarantine, mass decontamination, etc.), and helping to rebuild society following natural or man-made disasters. Generally speaking, emergency management is the ongoing process through which all people— individuals, organizations, and communities—manage risks in an effort to lessen the effect of catastrophes that may arise from those risks. The perception of danger by individuals who are exposed influences the actions that are taken.
Definition
The word “disaster” comes from the French word “disaster.”
A disaster is a state brought on by natural factors in which there is a significant disruption of services and infrastructure that has an adverse effect on the environment, the economy, and human life.

Introduction
Health patterns were impacted by environmental changes. Aspects of human health, including quality of life, that are influenced by environmental physical, chemical, biological, social, and psycho-social elements are collectively referred to
as environmental health (WHO). It describes the theory and practice of identifying, addressing, preventing, and managing environmental conditions that have a negative impact on the health of current and future generations.
The illness rickets is caused by the overcast atmosphere, which blocks off sunlight and prevents people from obtaining vitamin D from the sun. In Europe, the air quality that suppresses smoke and turns mist into smog is the cause of both lung cancer and chronic bronchitis. However, fair skin types with low pigmentation are more susceptible to skin cancer in bright sunlight. Cold and moisture have been linked to rheumatism. Ruminant animals get infections as a result of the absence of trace elements in the soil. Humidity and temperature have an impact on disease vectors. Malaria, yellow fever, dengue, encephalitis, filariasis, and other diseases are spread by mosquitoes.
Types of Diseases
The following is a classification of the primary illnesses that people suffer from:
• Deficiency diseases: These are conditions brought on by a person’s diet lacking in certain vital nutrients, such as vitamins, minerals, or amino acids. For example: Vitamin A deficiency, anemia, rickets, osteomalacia, and gum and tooth disorders.

1.1 Weather

Firstly, what is weather? Simply, the conditions in the atmosphere above the earth is called weather. It refers to the conditions such as wind, rain and temperature, prevailing at a particular location during periods of hours or days. We often ask “what’s the weather like today”? Any individual can answer to this question as it requires only a short term experience or say exposure to the atmosphere. The TV news forecasters predict weather each day and inform about the temperature, cloudiness, humidity, or possibility of storm in the next few days. Weather is localised, say, it’s a hot and cloudy weather in one part of the country and dry and windy on the other part.

1.1.1 What are the factors that influence weather?

Before we try to understand the factors that influence weather, we must understand what the components that describe a weather conditions are? Is it the rains, or the air temperature or both? The answer to this question is not so easy, and it’s a bit complicated. There are many components that constitute weather. Weather components include rain, cloud cover, sunshine, winds, hail, snow, sleet, storms, thunderstorms, heat waves and many more. These components are sometimes referred as weather parameters or climate elements. Each of these components define weather patterns of a particular area. These components determine the status of local atmospheric conditions. Again, as a basic definition, weather is the state of the atmosphere and majority of weather phenomena occur in the lowest layer of the atmosphere, called as the troposphere. Does it mean that ground conditions such as the topography, water bodies and vegetation of a particular area has nothing to do with it? No, it is not so. The state of the atmosphere is subjected to various processes taking place not only in the atmosphere but also in the ocean, the sea-ice, the vegetation, etc. Weather parameters or the components of weather form a sequence of events, and the influences are far reaching and they do not remain solely in the atmosphere. For example, terrestrial radiation impacts the air temperature, air pressure and humidity. The terrestrial location also influences the cloud formation. The clouds may or may not turn into precipitation depending on the outcome (cloud or rain), which is by and large governed by troposphere. Likewise, a lack of precipitation affects not only weather conditions, but also soil moisture conditions that may result in lowering of water levels (ground water table) in soil. Wind speed and direction are governed by the atmospheric pressure and air temperature. So, all these parameters or components are interrelated and the weather conditions are the outcome of their interactions. Therefore, we can say that, the three main components of weather are temperature, precipitation and solar radiation. These components are influenced by different factors.

Climate change is caused by both natural as well as anthropogenic causes and it has been changing since the inception of earth-atmosphere (Figure 2.1). In a broader sense, anthropogenic activities (human activities) also must be considered as natural one in longer time scale as human and their activities are also a part of natural-ecosystem-functions. Among the natural phenomena, volcanic eruptions and continental drifts significantly affect the earth’s precipitation and temperature. A huge volume of CO₂ is released due to volcanic eruption at a little span of time-period which heated up the earth-atmosphere. Climate variability is primarily governed by rise in sea temperature, movement of warm water from the Western Pacific towards Peru, and El Nino which occurs at an intervals of 3-7 years. Climate variability also influenced the alteration in temperature and precipitation world wide. And persistent climate variability cause long term climate change. Therefore, basically three drivers that causes climate change are, the alteration in the energy of sun received by earth-atmosphere (natural causes), variations of ref lectivity of earth-surface- atmosphere system (natural as well as anthropogenic causes) and fluctuations in the greenhouse effect (natural as well as anthropogenic causes).