BCA CCE Environmental Studies - BCASPOT ASSIGNMENT Answer (CY-2013 AY 2013-2014)

TAMIL NADU OPEN UNIVERSITY

School of Computer Science

SPOT ASSIGNMENT (CY-2013/AY 2012-2013)

NOTE : Part A Contains 3 Questions and will carry 5 Marks each, Part B Contain 1 Question and will carry 10 Marks. Students are requested to write 150 words and should not exceed 2 pages each in Part A,  300 words and should not exceed 4 pages in Part B.   Refer TNOU Materials.

Bachelor of Computer Applications

Second Year

Course Code : CCE

Course Title : ENVIRONMENTAL STUDIES

(Total Marks=25)

Part- A- Short Answer Questions

Answer all questions                                                                      (3 X 5 = 15 Marks)

1.      Explain the various components of natural resources.

Answer:

          Natural resources occur naturally within environments that exist relatively undisturbed by humanity, in a natural form. A natural resource is often characterized by amounts of biodiversity and geodiversity existent in various ecosystems.

•        Potential Resources – Potential resources are those that exist in a region and may be used in the future. For example, petroleum may exist in many parts of India, having sedimentary rocks but until the time it is actually drilled out and put into use, it remains a potential resource.

•        Actual Resources – Actual resources are those that have been surveyed, their quantity and quality determined and are being used in present times. The development of an actual resource, such as wood processing depends upon the technology available and the cost involved.

•        Reserve Resources – The part of an actual resource which can be developed profitably in the future is called a reserve resource.

•        Stock Resources – Stock resources are those that have been surveyed but cannot be used by organisms due to lack of technology. For example: hydrogen.

Renewable resources are ones that can be replenished naturally. Some of these resources, like sunlight, air, wind, etc., are continuously available and their quantity is not noticeably affected by human consumption.

Non-renewable resources are resources that form extremely slowly and those that do not naturally form in the environment. Minerals are the most common resource included in this category. By the human perspective, resources are non-renewable when their rate of consumption exceeds the rate of replenishment/recovery; a good example of this are fossil fuels, which are in this category because their rate of formation is extremely slow (potentially millions of years), meaning they are considered non-renewable.

2.      Explain the various components of ecosystem.

Answer:

An ecosystem is a community of living organisms (plants, animals and microbes) in conjunction with the nonliving components of their environment (things like air, water and mineral soil), interacting as a system.] These biotic and abiotic components are regarded as linked together through nutrient cycles and energy flows.As ecosystems are defined by the network of interactions among organisms, and between organisms and their environment, they can be of any size but usually encompass specific, limited spaces (although some scientists say that the entire planet is an ecosystem).

Energy, water, nitrogen and soil minerals are other essential abiotic components of an ecosystem. The energy that flows through ecosystems is obtained primarily from the sun. It generally enters the system through photosynthesis, a process that also captures carbon from the atmosphere. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.

3.      Define the following

a.    “Food Web”

b.    Green house effect

Answer:

Food Web:

A food web (or food cycle) depicts feeding connections (what-eats-what) in an ecological community and hence is also referred to as a consumer-resource system. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs. To maintain their bodies, grow, develop, and to reproduce, autotrophs produce organic matter from inorganic substances, including both minerals and gases such as carbon dioxide. These chemical reactions require energy, which mainly comes from the sun and largely by photosynthesis, although a very small amount comes from hydrothermal vents and hot springs. A gradient exists between trophic levels running from complete autotrophs that obtain their sole source of carbon from the atmosphere, to mixotrophs (such as carnivorous plants) that are autotrophic organisms that partially obtain organic matter from sources other than the atmosphere, and complete heterotrophs that must feed to obtain organic matter. The linkages in a food web illustrate the feeding pathways, such as where heterotrophs obtain organic matter by feeding on autotrophs and other heterotrophs. The food web is a simplified illustration of the various methods of feeding that links an ecosystem into a unified system of exchange. There are different kinds of feeding relations that can be roughly divided into herbivory, carnivory, scavenging and parasitism. Some of the organic matter eaten by heterotrophs, such as sugars, provides energy.

Green house effect:

The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases.

If an ideal thermally conductive blackbody was the same distance from the Sun as the Earth is, it would have a temperature of about 5.3 °C. However, since the Earth reflects about 30%of the incoming sunlight, this idealized planet's effective temperature (the temperature of a blackbody that would emit the same amount of radiation) would be about −18 °C. The surface temperature of this hypothetical planet is 33 °C below Earth's actual surface temperature of approximately 14 °C. The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect.

Part- B- Long Answer Question

Answer the following question                                                     (1 X 10 = 10 Marks)

1. a.  Discuss the various legal measures to prevent the environmental          

           pollution.

b.  India as a mega biodiversity country – Discuss.

Answer:

a)      Pollution prevention (P2) describes activities that reduce the amount of pollution generated by a process, whether it is consumer consumption, driving, or industrial production. In contrast to most pollution control strategies, which seek to manage a pollutant after it is formed and reduce its impact upon the environment, the pollution prevention approach seeks to increase the efficiency of a process, thereby reducing the amount of pollution generated at its source. Although there is wide agreement that source reduction is the preferred strategy, some professionals also use the term pollution prevention to include Pollution Prevention With the ever-rising human population, pollution has become a great concern. Pollution from human activities is a problem that does not have to be inevitable. With a comprehensive pollution prevention programme, most pollution can be reduced, reused, or prevented. The purpose of this paper is to introduce a pollution prevention programme that will demonstrate how to stabilize the population growth as well as how to reduce and manage waste to prevent further pollution to the planet. Human Population Numbers With nearly seven billion people in the world, and the fact that the average person produces 4.4 pounds of waste each day, around a ton of waste every year, it is easy to see why pollution is such a huge problem (Recycling Revolution, 2010). In order to slow the growing levels of pollution, the human population needs to stabilize. Population numbers are rapidly increasing in developing countries. It is estimated that “the human population will increase by one billion people in the next decade” The math is staggering when you add a ton a waste per person per year. Growth in these developing countries is partly due to developing countries governments telling their citizens that more numbers are needed to fill in the open spaces as the West has More people equals more natural resources used and waste created. The human population growth is the largest environmental problem the world faces. Slowing the Population Growth What can be done to slow the human population growth? “Experience shows that the most effective ways to slow human population growth are to encourage family planning, to reduce poverty, and to elevate the status of women Such plans and strategies can be converted into policies to ensure sustainability. “Action plans and strategies can be developed to increase public understanding of how rapid population growth limits chances for meeting basic

b)      India as a mega biodiversity country – Discuss.

India is one of the 12 mega biodiversity countries in the world. The country is divided into 10 biogeographic regions. The diverse physical features and climatic situations haveformed ecological habitats like forests, grasslands, wetlands, coastal and marine  ecosystems and desert ecosystems, which harbor and sustain immense biodiversity.

Biogeographically, India is situated at the tri-junction of three realms - Afro-tropical, Indo-Malayan and Paleo-Arctic realms, and therefore, has characteristic elements from each of them. This assemblage of three distinct realms makes the country rich and unique in biological diversity.

The country is also one of the 12 primary centres of origin of cultivated plants and domesticated animals. It is considered to be the homeland of 167 important plant species of cereals, millets, fruits, condiments, vegetables, pulses, fibre crops and oilseeds, and 114 breeds of domesticated animals.

Hot- spots of Biodiversity

A biodiversity hotspot is a biogeographic region with a significant reservoir

of biodiversity that is threatened with destruction.

An area is designated as a hot spot when it contains at least 0.5% of plant species as

endemic.

There are 25 such hot spots of biodiversity on a global level, out of which two are

present in India.

These are:

⇒ Indo- Burma (earlier The Eastern Himalayas) and

⇒ The western Ghats & Sri Lanka

These hot spots covering less than 2% of the world’s land area are found to have about

50% of the terrestrial biodiversity.