2. Environmental Science............................................................................................................. 3
Introduction..........................................................................................................................................................3
Ecosystem Structure and Function .......................................................................................................................4
Natural Resource Conservation ............................................................................................................................4
Environmental Pollution Control ..........................................................................................................................4
Environmental management ................................................................................................................................5
The scope of environmental studies in industry...................................................................................................5
Research and development ..................................................................................................................................5
Social Development ..............................................................................................................................................5
Need for public awareness Ecosystems Concept...............................................................................6
Structure of Ecosystem.....................................................................................................................6
(a) Abiotic Component..........................................................................................................................................6
(b) Biotic Component............................................................................................................................................7
1. Autotrophic Components or Producers............................................................................................................8
2. Heterotroph Components or Consumers .........................................................................................................8
Functions of Ecosystem....................................................................................................................9
Restoration of damaged ecosystems ..................................................................................... 10
Disturbance.........................................................................................................................................................10
Genetics ..............................................................................................................................................................10
Succession...........................................................................................................................................................10
Community Assembly Theory.............................................................................................................................10
Landscape Ecology..............................................................................................................................................11
Application..........................................................................................................................................................11
Biodiversity ........................................................................................................................... 12
Definition ............................................................................................................................................................12
Genetic diversity .................................................................................................................................................13
Species diversity..................................................................................................................................................13
Ecosystem diversity ............................................................................................................................................13
Description at national and global level.......................................................................................... 13
Biodiversity, business and industry.................................................................................................................13
Biodiversity, leisure, cultural and aesthetic value ..............................................................................................14
The Eastern Himalayas ................................................................................................................... 14
Biodiversity in Australia ......................................................................................................................................15
Threats Conservation Natural Resources ............................................................................... 15
Threats................................................................................................................................................................15
Conservation Natural Resources.........................................................................................................................16
This unique degree offers two majors................................................................................................................16
Renewable..................................................................................................................................... 16
Non- Renewable ............................................................................................................................ 17
Material cycles............................................................................................................................... 17
3. Carbon cycles......................................................................................................................................................17
Carbon Cycle One: Long-term Cycle ...................................................................................................................18
Nitrogen Cycle.....................................................................................................................................................19
Sulfur Cycle .........................................................................................................................................................19
Conventional and Non-conventional Energy Sources...................................................................... 21
Conventional Sources of Energy .........................................................................................................................21
Non-Conventional Sources of Energy .................................................................................................................21
Hydroelectric energy...................................................................................................................... 21
Biomass energy.............................................................................................................................. 22
Solar energy................................................................................................................................... 22
Wind energy .................................................................................................................................. 23
Biodiesel energy............................................................................................................................. 24
Hydrogen as an alternative fuel ............................................................................................ 24
Environmental Science
Introduction
Environmental science is a multidisciplinary academic field that integrates physical, biological
and information sciences, (including but not limited to ecology, physics, chemistry, zoology,
mineralogy, oceanology, limnology, soil science, geology, atmospheric science, geography and
geodesy) to the study of the environment, and the solution of environmental problems.
Environmental science provides an integrated, quantitative, and interdisciplinary approach to the
study of environmental systems. Related areas of study include environmental studies and
environmental engineering. Environmental studies incorporates more of the social sciences for
understanding human relationships, perceptions and policies towards the environment.
Environmental engineering focuses on design and technology for improving environmental
quality in every aspect. Environmental scientists work on subjects like the understanding of earth
processes, evaluating alternative energy systems, pollution control and mitigation, natural
resource management, and the effects of global climate change. Environmental issues almost
always include an interaction of physical, chemical, and biological processes. Environmental
scientists bring a systems approach to the analysis of environmental problems. Key elements of
an effective environmental scientist include the ability to relate space, and time relationships as
well as quantitative analysis.
4. Definition
Environmental science is the study of nature and the facts about environment. Basically
environment can be defined as “all the social, economical, physical & chemical factors that
surrounds man” (or) “all abiotic and biotic components around man-all living and non living
things surrounds man”.
Scope
Because of environmental studies has been seen to be multidisciplinary in nature so it is
considered to be a subject with great scope. Environment are not limited to issues of sanitation
and health but it is now concerned with pollution control, biodiversity conservation, waste
management and conservation of natural resources. This requires expert eyes and hence are
creating new job opportunities. The opportunities in this field are immense not only for scientists
but also for engineers, biologists. There is a good chance of opportunity to find a job in this field
as environmental journalists. Environmental science can be applied in the following spheres:
Ecosystem Structure and Function
The study of ecosystems mainly consists of the study of the processes that link the leaving
organism or in other words biotic component to the non-living organism or abiotic component.
So for the study of environment we should aware with biotic and abiotic components.
Natural Resource Conservation
For managing and maintenance of forests which are natural resources and for the maintenance of
wildlife forms task under natural resource conservation. It is also a scope of environmental
studies.
Environmental Pollution Control
With the knowledge of environmental science everybody can control the pollution. He/she can
handle the waste management and also look for ways to control pollution on the aspect of
pollution control.
5. Environmental management
There are several independent environmental consultants who are working with Central and State
pollution control Board. They offer advice to solve the problems of environment the optimum
solution for the upcoming problems. They give direction for controlling pollution due to
industrial development. There are several current consultants who are working with government
pollution control boobs, involved in policy making, pollution control, maintenance of ecological
balance.
The scope of environmental studies in industry
Environmental scientists work towards maintenance of ecological balance, they also work
towards conservation of biodiversity and regulation of natural resources as well as on
preservation of natural resources. Most of the industries have a separate environmental research
and development section. These sections govern the impact that their industry has on the
environment. Our environment is being degraded by the rapid industrialization. To combat this
menace there is a growing trend towards manufacture of "green" goods and products. So we can
say that there is a good scope in the field of industry from environmental studies.
Research and development
Research and development has tremendous scope due to increment in public awareness regarding
the environment. Various universities and governmental organizations offer a scope for such
research. These universities conduct research studies in order to develop the methods toward
monitoring and controlling the source of environmental pollution. Due to an increasing threat
from global warming , many steps are being undertaken for the reduction of greenhouse gases
and the adoption of renewable energy resources. They generate awareness now regarding the use
of solar energy for variety of purposes. This provide scope of environmental history in the field
of research and development.
Social Development
NGO ( nongovernmental organizations )help in creating awareness regarding the protection of
the environment and making the masses aware of various environmental issues . They also
generate a public opinion in this field. They work towards disseminating information and in
bringing about changes in political policies that are personally effect the environment. The social
6. dimension of this profession includes controlling population explosion through organizing
advisory awareness camps.
Need for public awareness Ecosystems Concept
Environmental studies helps to maintain ecological balance by providing a basic knowledge of
environmental systems and their processes. By giving information regarding the changes that
take place due to anthropogenic factors environmentally study helps us.
It also helps to gain a skill in using techniques to analyze various environmental systems and the
effect of human activities on that system.
• Environmental studies apply economical methods and concepts to issues of the
environment, management, environmental policy analysis. Environmental study includes
diverse area such as property rights, economic instruments for pollution control, cost
benefit analysis management applications with environmental policy.
• Concepts from environmentally studied can be applied to the study of agriculture and the
design of sustainable production systems.
• We need to a study of physical, biological, chemical and social processes that form the
basic of the problem of environment. Environmentally studies provide skills necessary to
raise the questions and too often obtain answers to some of the environmental problems
from which our planet is facing today.
Structure of Ecosystem
(a) Abiotic Component
1. Components, those are non-living are called abiotic components.
2. They have a strong influence on the structure, distribution, behaviour and interrelationship of
organisms.
Abiotic components are mainly of two types:
(i) Climatic factors: which include rain, temperature, light, wind, humidity pH, organic inorganic
components, minerals etc?
(ii) Edaphic factors: Which includes pH, organic, inorganic components, minerals etc?
7. (b) Biotic Component
1. The living organisms including plants, animals and microorganisms (Bacteria and fungi)! that
are present in an ecosystem form the biotic components.
2. On the basis of their role in the ecosystem the biotic component can be classified into three
main groups.
(i) Producers
(ii) Consumers
(iii) Decomposers or Reducers
(i) Producers:
1. Autotrophic plants are main producers.
2. These are capable of synthesize food from non-living components.
3. In this chemosynthesis bacteria also included.
4. As the green plants manufacture their own food they are known as Autotrophs.
(ii) Consumers
1. The animals lack chlorophyll and are unable to synthesise their own food.
2. Therefore, they depend on the producer, for their food. They are known as heterotrophs. The
consumer's are of four types, namely:
(a) Primary Consumers (Herbivores)
1. These are the animals, which feed on plants or the producers. They are called herbivores.
Examples: Rabbit, dear, goat, cattle, grasshopper etc.
(b) Secondary Consumers or Primary Carnivores
2. The animals, which feed on the herbivores, are called the primary carnivores. Examples: Cats,
dogs, fox, snakes etc.
(c) Tertiary Consumers or Secondary Carnivores
8. 1. These are the large carnivores which feed on the secondary consumers. Examples: Wolves.
(d) Quaternary Consumers or Omnivores
2. These are the largest carnivores, which feed on the tertiary consumers and are not eaten up by
any other animal.
Examples: Lions and tigers.
(iii) Decomposers or Reducers
1. Bacteria and fungi belong to this category. They breakdown the dead organic materials of
producers and Consumers for their food and release to the environment the simple inorganic and
organic substances product as byproducts of their metabolisms
2. The producers resulting in a cycling exchange of materials between the biotic community and
the abiotic environment of the ecosystem reuse these simple substances.
3. The decomposers are known as saprophytes.
On the nourishment standpoint, biotic components may be divided into two groups:
1. Autotrophic Components or Producers
The producers, which are mainly autotrophic green plants and certain photosynthetic or
chemosynthetic bacteria, which can convert the light energy of sun into potential chemical
energy in the form of organic compounds, needed by plant for their development. Thus
producers stand as intermediaries between the inorganic and organic world. They obtain C02
from the atmosphere and release 02 instead. About 99 percent of living mantle of earth is a
producer. They produce oxygen as a byproduct of photosynthesis, needed by all living organisms
for respiration.
2. Heterotroph Components or Consumers
These are mainly animals, including man, which have an intake of organic material as food,
which is provided in the first instance by autotrophs. In heterotrophic components, utilisation,
rearrangement and decomposition of complex materials predominate. The consumers are further
subdivided into two groups:
(A) Macroconsumers:
9. These consist of relatively larger consumers. They all phagotrophs which include chiefly animals
that ingest other organic and particulate organic they are of two types:
(i) Herbivores:
They are primary consumers and feed on the plants. Depending upo nature of plant part eaten by
them, they can be of different types like root f' sucking animals, bark feeders and eaters etc. They
may be large cattle, goats etc.
(ii) Carnivores:
They are secondary and tertiary consumers. They feed on flesh of animals. The carnivores,
which feed on secondary consumers, are known as consumers and so on. The carnivores, which
are not further preyed upon are c top carnivores, e.g., tiger.
(B) Micro Consumers:
These are minute to small and microscopic animals. They three types:
(i) Parasites:
A parasite is an organism that lives on or in the body of another deriving benefit at the expense
of the latter. The organism, which harbours the is called the "host." The parasite is always
benefitted in this association and then injured or harmed.
Functions of Ecosystem
• Aquatic ecosystem
o Marine ecosystem
Large marine ecosystem
o Freshwater ecosystem
Lake ecosystem
River ecosystem
Wetland
• Terrestrial ecosystem
• Forest
• Greater Yellowstone Ecosystem
• Littoral zone
10. • Riparian zone
• Subsurface lithoautotrophic microbial ecosystem
• Urban ecosystem
• Movile Cave
• Desert
Restoration of damaged ecosystems
Disturbance
Disturbance events can occur at many scales and different levels of severity, and some are
natural parts of every ecosystem. Disturbance events can alter species composition, nutrient
cycling, and soil properties. Natural disturbances include severe weather damage, fire, flooding,
treefalls and even volcanic eruptions. Anthropogenic (human-caused) disturbances can alter or
destroy natural habitat (like clearing land for agriculture) and/or ecological functions (like
damming rivers for flood control). Humans can also change natural disturbance events and
cycles (like suppression of wildfires and prevention of periodic flooding). The goal of a
restoration project may be to initiate or speed the recovery of an ecosystem after disturbance.
Restoration activities may also be designed to reestablish natural disturbance regimes.
Genetics
Restoration projects also typically include genetic considerations. Plants (or animals) from local
sources are more likely to be well adapted to the target ecosystem. Therefore, using animals or
plant materials (like seeds or cuttings) collected from local sources may increase the chance of
successful establishment. Including a large number of individual plants or animals can help
ensure genetic diversity in the restored populations. Genetic diversity is thought to be critical to
maintaining the ability of populations to evolve and recover from disturbances.
Succession
Ecological succession is the process by which biological community composition- the number
and proportion of different species in an ecosystem- recover over time following a disturbance
event. Passive restoration means simply allowing natural succession to occur in an ecosystem
after removing a source of disturbance. The recovery of the deciduous forests in the eastern
United States after the abandonment of agriculture is a classic example of passive restoration.
Active restoration involves accelerating the process or attempting to change the trajectory of
succession. For example, mine tailings would take so long to recover passively that active
restoration is usually appropriate.
Community Assembly Theory
Community assembly theory suggests that similar sites can develop different biological
communities depending on order of arrival of different species. In the context of restoration, sites
11. may not always recover toward a desired or anticipated group of species or ecosystem functions.
Composition of seed mixes, planting order and year of planting may be important considerations
for restoration practitioners, particularly when goals include the establishment of certain
ecological communities or the prevention of invasion by weeds or pests.
Landscape Ecology
Restoration draws on several concepts from landscape ecology. Restored areas are often
relatively small and isolated, which makes them especially sensitive to problems associated with
habitat fragmentation. Habitat fragmentation occurs when continuous areas of habitat become
disconnected by natural or human causes (for example, building roads through a forest).
Fragmentation generally leads to small, isolated patches of hospitable habitat. Smaller habitats
support fewer species and smaller populations, which are at greater risk of inbreeding and local
extinction. The theory of island biogeography predicts that populations are more likely to persist
in habitat patches that are large and/or well connected with populations in other hospitable
habitats. This theory assumes that the matrix—the region between habitat patches—is uniform
and inhospitable. The most common examples of this concept are oceanic islands, dots of
terrestrial species’ habitat surrounded by uninhabitable water. More recently, the classic
dichotomy of hospitable versus inhospitable habitat has been modified to include the existence a
multiple types of habitat patches which are juxtaposed to form a patch mosaic. These different
patches within the mosaic may be more or less hospitable for the species, communities and
ecosystem functions targeted by restoration activities.
Fragmentation may also intensify negative edge effects — impacts of one habitat on an adjacent
habitat — by increasing the amount of edge habitat and reducing the distances among edges. For
instance, invasive weeds are more abundant along forest edges, so small forest fragments (which
have more edge habitat) are more likely to be invaded. Restoration activities often seek to
improve connectivity among habitat patches in fragmented landscapes by creating or restoring
linkages. Examples of linkages commonly used to improve connectivity are corridors and
stepping stones. Corridors are relatively narrow, linear strips of habitat between otherwise
isolated habitat patches. Stepping stones are small unconnected patches of habitat that are close
enough together to allow movement across the landscape.
Application
Applied restoration is a multi-step process, which may include some or all of these stages:
• Assessing the site: A thorough appraisal of the current conditions at the restoration site is
essential for determining what kind of actions will be necessary. In this step, the causes
of ecosystem disturbance and methods for stopping or reversing them are identified.
• Formulating project goals: To determine targets for the restored community, practitioners
may visit reference sites (similar, nearby environments in natural condition) and/or
consult historical sources that detail the pre-disturbance community. Goals may also
12. include considerations of what species will be best suited to present or future climate
conditions.
• Removing sources of disturbance: Before restoration can be successful, forces of
disturbance may need to be removed. Examples include cessation of mining or farming or
causes of erosion, restricting livestock from riparian areas, removing toxic materials from
soil or sediments, and eradicating invasive exotic species.
• Restoring processes/disturbance cycles: Sometimes restoring important ecological
processes such as natural flood or fire regimes is enough to restore ecosystem integrity.
In these cases, native plants and animals that have evolved to tolerate or require natural
disturbance regimes may come back on their own without direct action by practitioners.
• Rehabilitating substrates: This can include any activity aimed at repairing altered soil
texture or chemistry, or restoring hydrological regimes or water quality.
• Restoring vegetation: In many cases, restoration activities involve direct revegetation of a
site. Usually, native species suited to local environmental conditions are chosen for
planting. Seeds or cuttings are generally collected from a variety of sources within a local
region in order to ensure genetic diversity. Vegetation can be planted as seeds, or
seedlings.
• Monitoring and maintenance: Monitoring the restoration site over time is critical to
determining whether goals are being met, and can inform future management decisions.
Observations made at the site may indicate that further action, such as periodic weed
removal, is necessary in ensuring the long-term success of the project. Ideally restoration
projects would eventually achieve a self-sustaining ecosystem without the need for future
human intervention.
Biodiversity
Definition
Biological diversity, or the shorter "biodiversity," (bio-di-ver-si-ty) simply means the diversity,
or variety, of plants and animals and other living things in a particular area or region. For
instance, the species that inhabit Los Angeles are different from those in San Francisco, and
desert plants and animals have different characteristics and needs than those in the mountains,
even though some of the same species can be found in all of those areas.
Biodiversity also means the number, or abundance of different species living within a particular
region. Scientists sometimes refer to the biodiversity of an ecosystem, a natural area made up of
a community of plants, animals, and other living things in a particular physical and chemical
environment.
13. In practice, "biodiversity" suggests sustaining the diversity of species in each ecosystem as we
plan human activities that affect the use of the land and natural resources.
Genetic diversity
This represents the heritable variation within and between populations of organisms. Ultimately,
this resides in variations in the sequence of the four base-pairs which, as components of nucleic
acids, constitute the genetic code.
Species diversity
Perhaps because the living world is most widely considered in terms of species, biodiversity is
very commonly used as a synonym of species diversity, in particular of 'species richness', which
is the number of species in a site or habitat. Discussion of global biodiversity is typically
presented in terms of global numbers of species in different taxonomic groups. An estimated 1.8
million species have been described to date; estimates for the total number of species existing on
earth at present vary from 5 milliion to nearly 100 million. A conservative working estimate
suggests there might be around 12.5 million. In terms of species numbers alone, life on earth
appears to consist essentially of insects and microorganisms.
Ecosystem diversity
The quantitative assessment of diversity at the ecosystem, habitat or community level remains
problematic. Whilst it is possible to define what is in principle meant by genetic and species
diversity, and to produce various measures thereof, there is no unique definition and
classification of ecosystems at the global level, and it is thus difficult in practice to assess
ecosystem diversity other than on a local or regional basis and then only largely in terms of
vegetation. Ecosystems further differ from genes and species in that they explicitly include
abiotic components, being partly determined by soil parent material and climate.
Description at national and global level
Biodiversity, business and industry
14. Agriculture production, pictured is a tractor and a chaser bin
Many industrial materials derive directly from biological sources. These include building
materials, fibers, dyes, rubber and oil. Biodiversity is also important to the security of resources
such as water, timber, paper, fiber, and food. As a result, biodiversity loss is a significant risk
factor in business development and a threat to long term economic sustainability.
Biodiversity, leisure, cultural and aesthetic value
Biodiversity enriches leisure activities such as hiking, birdwatching or natural history study.
Biodiversity inspires musicians, painters, sculptors, writers and other artists. Many cultures view
themselves as an integral part of the natural world which requires them to respect other living
organisms. Popular activities such as gardening, fishkeeping and specimen collecting strongly
depend on biodiversity. The number of species involved in such pursuits is in the tens of
thousands, though the majority do not enter commerce. The relationships between the original
natural areas of these often exotic animals and plants and commercial collectors, suppliers,
breeders, propagators and those who promote their understanding and enjoyment are complex
and poorly understood. The general public responds well to exposure to rare and unusual
organisms, reflecting their inherent value. Philosophically it could be argued that biodiversity has
intrinsic aesthetic and spiritual value to mankind in and of itself. This idea can be used as a
counterweight to the notion that tropical forests and other ecological realms are only worthy of
conservation because of the services they provide.
The Eastern Himalayas
The Eastern Himalayas is the region encompassing Bhutan, northeastern India, and southern,
central, and eastern Nepal. The region is geologically young and shows high altitudinal variation.
It has nearly 163 globally threatened species including the One-horned Rhinoceros (Rhinoceros
unicornis), the Wild Asian Water buffalo (Bubalus bubalis (Arnee)) and in all 45 mammals, 50
birds, 17 reptiles, 12 amphibians, 3 invertebrate and 36 plant species. The Relict Dragonfly
(Epiophlebia laidlawi) is an endangered species found here with the only other species in the
genus being found in Japan. The region is also home to the Himalayan Newt (Tylototriton
verrucosus), the only salamander species found within Indian limits.
15. Biodiversity in Australia
Australia was once part of the great southern landmass Gondwana, which also included South
America, Africa, India and Antarctica. Gondwana began to break up around 180 million years
ago, with Australia eventually splitting from Antarctica about 45 million years ago.
Australia is home to large numbers of species that occur nowhere else in the world. Over 80% of
our plants and mammals, and 45% of our birds live only here. These unique species have
evolved largely due to Australia’s long isolation from other continents and their adaptation to
Australia’s varied environments and changing climate.
Australia is identified as one of the world’s 17 “megadiverse” countries. The concept of
megadiversity is based on the total number of species in a country and the degree of endemism,
or the extent to which organisms are unique to that country. Together, these 17 countries harbour
more than 70% of the Earth’s species.
Of those megadiverse nations Australia and the USA are in the highest income category, with
well developed economies, and the resources needed to deal with environmental problems.
This presents an opportunity for us to demonstrate world leadership in biodiversity conservation
and to provide a high standard of biodiversity protection across our continent.
Threats Conservation Natural Resources
Threats
Many of the threats to biodiversity, including disease and climate change, are reaching inside
borders of protected areas, leaving them 'not-so protected' (e.g. Yellowstone National Park).
Climate change, for example, is often cited as a serious threat in this regard, because there is a
feedback loop between species extinction and the release of carbon dioxide into the atmosphere.
The effects of global warming adds a catastrophic threat toward a mass extinction of global
biological diversity. The extinction threat is estimated to range from 15 to 37 percent of all
species by 2050, or 50 percent of all species over the next 50 years. Some of the most significant
and insidious threats to biodiversity and ecosystem processes include climate change, mass
agriculture, deforestation, overgrazing, slash-and-burn agriculture, urban development, wildlife
trade, light pollution and pesticide use. Habitat fragmentation poses one of the more difficult
challenges, because the global network of protected areas only covers 11.5% of the Earth's
surface. Roads are one cause of fragmentation, as well as a direct source of mortality for many
types of animals, but they can also have some beneficial effects. A significant consequence of
fragmentation and lack of linked protected areas is the reduction of animal migration on a global
scale. Considering that billions of tonnes of biomass are responsible for nutrient cycling across
the earth, the reduction of migration is a serious matter for conservation biology.
16. Conservation Natural Resources
Our society depends on the maintenance and protection of ecosystems. Yet resources in many
ecosystems are often over-exploited or managed in non-sustainable ways. Urban development,
agricultural, mineral/oil extraction, fisheries and forestry practices, can threaten the very
existence of some ecosystems and alter or eliminate important habitats, biodiversity, and
people’s way of life. Global climate change presents the largest uncertainty and threat to the
sustainablilty of our present natural resources and ecosystems. To maintain healthy ecosystems
we have to strive to achieve a balance between society’s ever-increasing need for goods and
services and protection of natural environments, and do so in an era of changing climate.The
Natural Resources Conservation Program provides students with skills and knowledge to meet
such challenges. Natural resources conservation is an important issue throughout
BC, Canada and the world. As a society, we choose which natural resources to use, and in what
manner these uses will take place. Conservation science is concerned with the maintenance of
habitats, the persistence of diverse natural resources, an understanding of human behaviours, and
recognizes that a balance is needed among environmental, social, economic, cultural, and
aesthetic values. Conservation scientists help society make the best possible environmental
choices for achieving resource sustainability.
This unique degree offers two majors
The Science and Management Major focuses on the conservation and management of renewable
natural resources, and landscape and local level planning for both terrestrial and aquatic
ecosystems.
The Global Perspectives Major focuses on the conservation and management of renewable and
non-renewable resources, policy formation and planning within a global context.Selecting a
Major: all students are by default in the Science and Management Major of the NRC program.
Students apply at end of year 2 to enter the Global Perspective Major. Because space is limted in
the Global Perspectives Major, the best 27 credits from the year of application will be used to
assess academic standing and to rank applicants.
Renewable
A renewable resource is a natural resource which can replenish with the passage of time, either
through biological reproduction or other naturally recurring processes. Renewable resources are
a part of Earth's natural environment and the largest components of its ecosphere. A positive life
cycle assessment is a key indicator of a resource's sustainability. In 1962, Paul Alfred Weiss
defined Renewable Resources as: "The total range of living organisms providing man with food,
fibers, drugs, etc...". Renewable resources may be the source of power for renewable energy.
17. However, if the rate at which the renewable resource is consumed exceeds its renewal rate,
renewal and sustainability will not be ensured. The term renewable resource also describes
systems like sustainable agriculture and water resources. Sustainable harvesting of renewable
resources (i.e., maintaining a positive renewal rate) can reduce air pollution, soil contamination,
habitat destruction and land degradation. Gasoline, coal, natural gas, diesel and other
commodities derived from fossil fuels, as well as minerals like copper and others, are non-
renewable resources without a sustainable yield.
Non- Renewable
A non-renewable resource (also known as a finite resource) is a resource that does not renew
itself at a sufficient rate for sustainable economic extraction in meaningful human time-frames.
An example is carbon-based, organically-derived fuel. The original organic material, with the aid
of heat and pressure, becomes a fuel such as oil or gas. Fossil fuels (such as coal, petroleum, and
natural gas), and certain aquifers are all non-renewable resources. Metal ores are other examples
of non-renewable resources. The metals themselves are present in vast amounts in the earth's
crust, and are continually concentrated and replenished over millions of years. However their
extraction by humans only occurs where they are concentrated by natural processes (such as
heat, pressure, organic activity, weathering and other processes) enough to become economically
viable to extract. These processes generally take from tens of thousands to millions of years. As
such, localized deposits of metal ores near the surface which can be extracted economically by
humans are non-renewable in human timeframes, but on a world scale, metal ores as a whole are
inexhaustible, because the amount vastly exceeds human demand, on all timeframes. In this
respect, metal ores are considered vastly greater in supply to fossil fuels because metal ores are
formed by crustal scale processes which make up a much larger portion of the earth's near-
surface environment than those that form fossil fuels, which are limited to areas where carbon-
based life forms flourish, die, and are quickly buried. These fossil fuel-forming environments
occurred extensively in the Carboniferous Period.
Material cycles
Carbon cycles
It is believed that most of the carbon now on Earth was originally released from the interior of
the Earth as CO2, a gas which now makes up about 0.03 to 0.04 percent by volume of air, and is
responsible for maintaining the Earth as a greenhouse with temperature conditions suitable for
life. CO2 is the most available form of carbon for living organisms. Molecules containing carbon
18. may keep the carbon fixed over millions of years or may cycle the carbon through quickly. The
atmospheric cycling and effects of CO2 on climate are discussed in the Atmospheric System.
Thus, carbon exists in the biosphere as the central element of life, in the lithosphere as coal
(carbon) or limestone (Calcium Carbonate, CaCO3 ), in the atmosphere as CO2, in the
hydrosphere as dissolved CO2 , as well as in other complex forms. The versatility of carbon
compounds and the vital role of carbon as the basis of life is described in Biological/Ecological
Systems. The atmosphere contains about 750 billion tons of carbon in the form of CO2.
Photosynthesis by plants removes about 120 billion tons of carbon from the air per year, but
plant decomposition returns about the same amount. Living plants and animals contain 560
billion tons of carbon (mostly forest trees). Plant remains and organic matter buried in the soil
contain about 1400 billion tons. About 11,000 billion tons are trapped in compounds which are
complexes of methane (CH4) and water, found on ocean floor. The oceans contain another
38,000 billion tons of carbon, most of it in the form of dissolved CO2.
With the onset of the Industrial Revolution about 200 years ago, we began burning massive
amounts of fossil fuels and releasing large amounts of the earthbound carbon into the
atmosphere, primarily as CO2. The burning of fossil fuels adds about 22 billion tons of CO2 per
year (?), containing about 6 billion tons of carbon. Deforestation adds a further 1.6 to 2.7 billion
tons, by not removing this amount. The rapid growth of synthetic organic chemicals contributes
to the amount of CO2 released.The main reservoirs for carbon are sedimentary rocks, fossilized
organic carbon including the fossil fuels, the oceans, and the biosphere. Carbon goes primarily
through three cycles with different time constraints:
1. A long-term cycle involving sediments and the depths of the lithosphere.
2. A cycle between the atmosphere and the land.
3. A cycle between the atmosphere and the oceans.
The last two cycles are faster and subject to human intervention.
Carbon Cycle One: Long-term Cycle
This cycling between atmosphere, oceans, and sediments involve a slow dissolution of
atmospheric carbon and carbon from rocks via weathering into the oceans. In turn, the oceans
deposit sediments, and then some of the sediments are thrown back into the atmosphere through
volcanic action.
19. Nitrogen Cycle
The nitrogen cycle is dominated by the N2 gas in the atmosphere. Nitrous oxide, N2O is the
second common form. N20 (the gas commonly known as laughing gas) is a greenhouse gas.
Seventy-nine percent of the atmosphere is nitrogen in the form of N2 gas. Because N2 has low
reactivity, it offsets the high reactivity of oxygen, O2, the other major constituents of the
atmosphere. For example when we light a match, the nitrogen does not burn with the oxygen. It
does not react with any other element or common compound under ordinary conditions. This
property of nitrogen has been called the "fire insurance" of our atmosphere. If the nitrogen was
not "diluting" the flammability of 02, every spark from a match could lead to a large fire! Due to
its different valences (3,4,5,), nitrogen can form a multiplicity of compounds into the same
element. For example, it can combine with oxygen to form N2O, NO, NO2, or N2O5! As a
group, these oxides are (except for N2O5) denoted by NOx. NOx compounds form an important
category of air pollutants, for example, as a result of the nitrogen and oxygen combining in the
extremely hot environment of an automobile engine. Nitrogen oxides and hydrocarbons, in the
presence of sunlight, give rise to the photochemical smog and tropospheric ozone problems,
described in the Atmospheric System. Natural and anthropogenic nitrogen oxides also contribute
to acid rain.
Sulfur Cycle
Sulfur is mainly found on Earth as sulfates in rocks or as free sulfur. The largest deposits of
sulfur in the United States are in Louisiana and Texas. Sulfur also occurs in combination with
several metals such as lead and mercury, as PbS and HgS. Sulfur appears as the yellow aspects
of soil in many regions. Sulfur was mined early in the form of the yellow element and used for
20. gunpowder and fireworks. While bacteria digest plant matter, they emit H2S, hydrogen sulfide, a
gas that has the "rotten egg" smell characteristic of swamps and sewage. Sulfur is an essential
element of biological molecules in small quantities. Sulfur and its compounds are important
elements of industrial processes. Sulfur dioxide (SO2) is a bleaching agent and is used to bleach
wood pulp for paper and fiber for various textiles such as wool, silk, or linen. SO2 is a colorless
gas that creates a choking sensation when breathed. It kills molds and bacteria. It is also used to
preserve dry fruits, like apples, apricots, and figs, and to clean out vats used for preparing
fermented foods such as cheese and wine. Sulfuric acid, H2SO4, is a very widely used chemical.
Over 30 million tonnes of sulfuric acid are produced every year in the U.S. alone. The acid has a
very strong affinity for water. It absorbs water and is used in various industrial processes as a
dehydrating agent. The acid in the automobile battery is H2SO4. It is used for "pickling" steel,
that is, to remove the oxide coating from the steel surface before it is coated with tin or
electroplated with zinc.Sulfur is also a biologically important atom. Although only small
amounts of sulfur are necessary for biological systems, disulfide bridges form a critical function
in giving biological important molecules specific shapes and properties. (See Biological
Systems.) Sulfur is released into the atmosphere through the burning of fossil fuels --especially
high sulfur coal--and is a primary constituent of acid rain. Sulfuric acid (H2SO4) is the primary
constituent of acid rain (see Atmospheric System) in about all regions other than California.
Sulfur dioxide and carbonyl sulfide (COS) occur in small quantities in the atmosphere; but due to
its high reactivity, sulfur is quickly deposited as compound (sulfates) on land and other surfaces.
Figure S1: The Sulfur Cycle.
21. Conventional and Non-conventional Energy Sources
Conventional Sources of Energy
I. The sources of energy which have been in use for a long time, e.g., coal, petroleum, natural gas
and water power.
II. They are exhaust able except water.
III. They cause pollution when used, as they emit smoke and ash.
IV. They are very expensive to be maintained, stored and transmitted as they are carried over
long distance through transmission grid and lines.
Non-Conventional Sources of Energy
I. The resources which are yet in the process of development over the past few years. It includes
solar, wind, tidal, biogas, and biomass, geothermal.
II. They are inexhaustible.
III. They are generally pollution free.
IV. Less expensive due to local use and easy to maintain.
Hydroelectric energy
Although this technology is not new, its wide application to small waterfalls and other potential
sites is new. It is best suited to high falls with low volume, such as occur in high valleys in the
mountains and in the High Selva. Thus ELECTROPERU (1979) conservatively estimates that at
least 1,000,000 KW could be generated in hydroelectric plants producing 100 to 1,000 KW. The
investment needed to provide this electricity to 1,186 isolated locations in Peru is high -
approximately US$1,500 per KW. The ELECTROPERU 1979-1985 Program of Investment for
Small Hydroelectric Plants has considered the construction of 14 plants in the high and low
forest regions, which would consume 25 percent of the total investment for small hydroelectric
plants during this period (Table 15-2). These plants are classified by power and size of waterfall
in Table 15-3.
INVESTMENT PROGRAM IN SMALL HYDROELECTRIC 1979-1985 (Peruvian Selva)
Locality Location Power
KW
Total Investments
(US$ thousands)
22. Pedro Ruiz Amazonas 230 -
Chincheros Amazonas 60 -
Satipo Junin 750 -
Mazamari Junin 400 500
Pichanaki Junin 500 400
Pozuzo Pasco 110 300
Paucartambo Cuzco 874 240
Quincemil Cuzco 500 400
Lamas San Martin 360 200
San Jose de Sisa San Martin 257 200
Tabolosos San Martin 400 300
Tres Unidos San Martin 200 00
Luya San Martin - 250
Jumbiya San Martin - 200
TOTAL $3,190
Biomass energy
The combustion of firewood, forest residues, and other cellulose residues produced by urban and
rural industry is the oldest process employed by man to provide energy for both domestic and
industrial purposes Firewood and agriculture and livestock residues (husks and manure)
contributed 33.8 percent of the primary energy consumed in Peru in 1976. This energy was not
used commercially, but was almost entirely employed in domestic and cottage industries, where
it would be more useful and efficient if first transformed to charcoal, a dry combustible material
of higher calorific value. As either wood or charcoal, it would be burned in the home in heat-
efficient stoves which can be made in cottage industries or factory-made classic stoves of iron.
Wood ovens can be used in small industries such as ceramics, brick-making, construction
materials for bread making, smelting and others.
Solar energy
The Peruvian Central Selva and the Amazonian humid tropics in general receive high amounts of
solar radiation. There are so many trees hiding the sun, however, that it was once thought too
difficult to directly exploit solar energy. Today, however, it is understood that such endeavors
could enhance integrated development in Central Selva. Solar energy can be used in low potency
thermal generation. For example: Heating of water is necessary for industrial and cottage
23. industry requirements, such as making cheese and preserves. Flat collector technology is widely
known, with many brands existing in the national marketplace. One of these is made in Peru,
licensed by ITINTEC which has been conducting research in this field since 1975. Solar
dehydration of agricultural products is the most promising solar energy option for the Central
Selva, considering the enormous difficulties that confront small farmers when preparing such
products as rice, bananas, and manioc for the market. A program to distribute appropriate solar
dehydration techniques to farmers can use equipment that optimizes the use of transparent plastic
in place of glass and that also dries products (rice) by creating forced air convection that is
heated by solar radiation of the product stored in vertical silos. Industrial concerns in Brazil can
provide and install such operations. Solar heating, on the other hand, is not practical in
households, but can be used for some production and livestock purposes. Potent thermal
generation also is possible using solar energy. Techniques exist to focus solar radiation on a
single point, which can transform the latent heat of liquid vaporization into closed primary
circuits. The absorbed heat is transferred to secondary circuits in series with mechanical works
(turbines), eventually generating electric energy (helioelectric plants). At present, these
techniques are in the experimental phase and are not yet competitive because of the very high
cost of their sophisticated mirror systems that move synchronously by computer to derive
maximum benefit from solar energy.
Photovoltaic generation is a technology that directly converts solar energy to electric energy
through the use of cells with monosilica and polycrystalline surfaces that act as semi-conductors.
It can probably supply the limited energy demands of remote and rural areas in the near future.
The technological advances appearing day after day in developed countries have reduced the cost
of energy produced by photovoltaic panels by five times since 1976; therefore, production has
increased, the products are of better quality, and their manufacture is now automated and uses
less expensive materials. Photovoltaic generation has its place in the integrated development of
the Central Selva, particularly in providing energy for telecommunications and television and for
water pumps and electrical service to homes in remote areas.
Wind energy
There is little potential for wind energy in Peru. Although no map exists that illustrates wind
patterns in the Peruvian forest, recent reconnaissance of the High Selva in San Martin, Pucallpa,
and Satipo did not detect winds with energy-producing potential. Nevertheless, before discarding
this option, and taking into account its unpredictability, wind velocity should be evaluated where
wind is being considered a potential energy-producer. Wind's application for mechanical (mills)
or electrical (aerogenerators) purposes would depend on the presence of continual wind; the
demand (water to be pumped or KW required); the design and dimensions of the equipment and;
whether equipment is produced nationally or locally.
24. Biodiesel energy
Biodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl
(methyl, ethyl, or propyl) esters. Biodiesel is typically made by chemically reacting lipids (e.g.,
vegetable oil, animal fat (tallow) with an alcohol producing fatty acid esters.Biodiesel is meant to
be used in standard diesel engines and is thus distinct from the vegetable and waste oils used to
fuel converted diesel engines. Biodiesel can be used alone, or blended with petrodiesel in any
proportions. Biodiesel can also be used as a low carbon alternative to heating oil.The National
Biodiesel Board (USA) also has a technical definition of "biodiesel" as a mono-alkyl ester
Hydrogen as an alternative fuel
Hydrogen is the ideal alternative fuel for Army After Next (AAN) platforms. However, while
hydrogen offers many benefits, there are two drawbacks to using it as a fuel with current
technology. Liquid hydrogen, the preferred form of hydrogen, requires four times the storage
space of conventional petroleum-based fuels. The other problem is that hydrogen production
depends on the availability of a nonrenewable resource, petroleum. Currently, hydrogen is
produced from raw petroleum for industrial use, but petroleum supplies may become limited in
the near future. Liquid hydrogen is the best alternative fuel for AAN platforms; however, further
research is needed to move the hydrogen fuel technologies from prototypes to usable military
hardware and to optimize power outputs from internal combustion engines (ICE's), gas turbine
engines, and fuel cells. Petroleum production is expected to decrease significantly by 2025, the
year that AAN concepts and force structures are scheduled to be operational. Current oil
production is 25 billion barrels of oil per year; by 2025, annual oil production most likely will be
between 18 and 19 billion barrels—less than the annual production during the oil shortages of
the 1970's. The predicted decrease, as well as possible interruption of imported oil due to
political instability in the Middle East, will result in increased petroleum prices. On the other
hand, high speed and high mobility will characterize the AAN battle force, and speed and
mobility mean high fuel consumption. The 1998 AAN Annual Report states, "An absolute
imperative exists to develop alternative fuels (nonfossil) . . . for AAN-era forces." The report
goes on to say that there are numerous alternatives to fossil fuels but does not specify what those
fuels are. In the January-February 1999 issue of Army Logistician, Lieutenant Colonel Allen
Forte recommends " . . . new systems [ought] to examine alternatives to fossil fuels as their first
option for a power source." Other writers have recommended that AAN planners develop
hydrogen as the fuel for AAN platforms; one unequivocally states, "The development of
hydrogen-based vehicles is a national imperative."
