Environment

Ecosystem and Biodiversity 

Quest. State the significance and scope of environmental education.

1. Through environmental studies, people will understand the concept of need for development without destruction of the environment.
2. To motivate, active participation in environmental protection and improvement.
3. Environmental studies develop concern and respect for the environment.

Quest. Give some important physical hazards and their health effects.

1. Physical hazards are the substance (or) activities that threaten your physical safety.
2. They will be present in most work places at one time or another; they can be detected through your senses of touch or sight.

Quest. Define the environment and ecosystem.

Environment: It is defined as the sum of total of all the living and non-living things around us influencing one another.

Ecosystem: A group of organisms interacting among themselves and with environment for exchanging energy and matter is known as ecosystem.

Quest. Differentiate between biome and an ecosystem.

Biome : A small ecosystem within an ecosystem is called as biome.

Ecosystem : A group of organisms interacting among themselves and with the environment for exchanging energy and matter is known as ecosystem

Quest. Mention the abiotic components.

The non-living components of an ecosystem called abiotic components.
Examples: climate, soil, water, air, energy, nutrients, etc.

Quest. Define primary and secondary production.

Primary production: The primary function of all ecosystems is to absorb sunlight and manufacture of starch.

Secondary production: The secondary function of all ecosystems is distributing energy in the form of food to all consumers or the energy stored by the consumer.

Quest. What is the major significance of biodiversity?  

1. We depend on plants, micro-organisms, earth’s animals for our food, medicine and industrial products.
2. Biodiversity protects the fresh air, clean water and productive land.

Quest. What is ecological succession?  

The progressive replacement of one community by another till the development of stable community in a particular area is called as ecological succession.

Quest. Define species diversity?

Species diversity is the diversity between different species. The sum of varieties of all the living organisms at the species level is known as species diversity.

Quest. India as Mega diversity nation – Account.

India is one among the 12mega-diversity countries in the world. It has 89,450 animal species accounting for 7.31% of the global faunal species and 47,000 plant species which accounts for 10.8% of the world floral species. The loss of biodiversity is about 33%.

Quest. Differentiate the food chain and food web with suitable examples.  

Food Chain: A food chain is a picture or model that shows the flow of energy from Autotrophs to a series of organisms in an environment. A food chain only follows just one path as animals find food.eg: A hawk eats a snake, which has eaten a frog, which has eaten a grasshopper, which has eaten grass.

Food web: A food web is several food chains connected together. A food web shows the many different paths plants and animals are connected. eg: A hawk might also eat a mouse, a squirrel, afrog or some other animal The snake may eat a beetle, a caterpillar, or some other animal.And so on for all the other animals in the food chain..

Quest. Define Ecological succession. 

“Ecological succession” is the observed process of change in the species structure of an ecological community over time. Within a y community some species may become less abundant over some time interval, or they may even va ish from the ecosystem altogether. Similarly, over some time interval, other species within the commu ity may become more abundant, or new species may even invade into the community from adjacent ecosystems. This observed change over time in what is living in a particular ecosystem is “ecological succession”.

Quest. What are the threats to Indian biodiversity?

Threats to Indian biodiversity- deforestation, destruction of wetlands, habitat fra mentation, raw material, production of drugs, illegal trade and developmental activities.

Quest. What do you understand by endangered species and endemic species?

Endangered and endemic species :–

Endemic species, which are found only in a particular region.

Endangered species, species is said to be threatened or endangered when its number has been reduced to a critical level.
Unless it is protected and conserved it is in immediate danger of extinction.

Quest. Explain threatened and endangered species.

Threatened and endangered species. –species is said to be threatened or endangered when its number has been reduced to a critical level. Unless it is protected and conserved it is in immediate danger of extinction.

Natural Resources

Quest. Distinguish Renewable and Non-renewable energy sources.

Renewable energy sources :Resources capable of being regenerated within a reasonable time period.
Example: Solar energy, wind energy.

Non-renewable energy sources: Resources not capable of being regenerated by ecological processes.
Example: Coal, petroleum.

Quest. Write the effects of timber extraction on forest & tribal people.  

1. Large scale timber extraction causes deforestation.
2. It also leads to loss of tribal culture and extinction of tribal people.
3. Timber extraction reduces thickness of the forest.

Quest. Mention the major environmental impacts of mining?  

1. Mining reduces the shape and size of the forest areas.
2. Pollution of surface and groundwater resources due to the discharge of waste minerals in water.

Quest. Explain overgrazing.

ANSWER: Overgrazing– A process of eating away of forests without giving it a chance to regenerate.

Quest. State the reasons for the overexploitation of forests. 

1. Shifting of Cultivation – 300 million people – 5 lakh hectares of forest for slash and burn culture
2. Fuel requirement
3. Raw materials for industrial use
4. Developmental projects
5. Growing food needs
6. Overgrazing
7. Forest fires

Quest. Write the ways of drought management. 

1. Selecting appropriate crop or plantation depending upon the climate, soil type .
2. Afforestation

Quest. Mention the major environmental impacts of Mining.

Impacts of Mining are:

1. Soil erosion,
2. Contamination of soil,
3. Loss of biodiversity,
4. Formation of sinkholes.

Quest. What are the changes caused due to overgrazing?  

The changes caused due to overgrazing: Overgrazing leads to

1. Loss of biodiversity,
2. Loss of minerals,
3. Soil erosion,
4. Leads to desertification.

Quest. What are the harmful effects of land degradation? 

Harmful effects of land degradation. –

1. Soil structure and texture are deteriorated,
2. loss of soil fertility due to loss of valuable nutrients,
3. increase in water logging, salinity, alkalinity, acidity problems.

Quest. What are Mineral Resources? Give its types.

Mineral resources are natural occurring substances having definite chemical composition and physical properties.

Types:

1. Identified resources,
2. Undiscovered resources,
3. Reserves.

Quest. What is eutrophication?

A large proportion of nitrogen and phosphorous fertilizers used in crop fields is washed off by the runoff water and reaches the water bodies causing over nourishment of the lakes. The process of accumulation of nutrients in the water bodies is known as eutrophication.

Quest. Define Water-logging. Write its consequences?

Water-logging is the land where water stand for most of the year. During water-logged conditions, pore-voids in the soil get filled with water and the soil air gets depleted. In such a condition the roots of the plants do not get adequate air for respiration. So mechanical strength of the soil decreases and crop yield falls.

Quest. What is land degradation? What are the causes of land degradation? 

Land degradation is the process of deterioration of soil or loss of fertility of the soil.

Causes:
Increase in population, fertilizers & water-logging.

Quest. What is desertification? Give any two reasons for it?

Desertification is a progressive destruction or degradation of arid or semiarid lands to desert. Desertification is characterized by DE vegetation, depletion of ground water, salination and soil erosion.

Quest. What is the role of an individual in conservation of natural resources?

Role of individual in the conservation of natural resources. – duty of every individual to conserve natural resource in such wa that it is available for future generations also.

Due to advancement IT technology and population growth, the present world is facing lot of problems on degradation of natural resource.

Quest. What is environmental biochemistry?

Environmental biochemistry involves approaches to treat polluted air, waste water and solid waste using metabolic activities of micro-organisms.

Environmental Pollution

Quest. Define Environmental Pollution.

Environmental Pollution is defined as any undesirable change in the physical, chemical, or biological characteristics of any component of the environment (air, water, soil) which can cause harmful effects on various forms of property.

Quest. Suggest four important sources of air pollution.

The sources of air pollution are volcanic eruptions, fest fires, biological decay, thermal power plants, vehicular emissions etc.,

Quest. What is meant by BOD and COD?

Biological Oxygen Demand (BOD): BOD is the amount of oxygen required for the biological decomposition of organic matter present in the water.

COD: COD is the amount of oxygen required f chemical oxidation of organic matter using oxidizing agent.

Quest. Name the sources and effects of marine pollution.

Effects:

The continuous oil films inhibit photosynthesis and absorption of oxygen. This inhibits the growth of plankton. All aquatic animals depend either directly indirectly on plankton, which is the basis of the tropic chain. 

Sources: Dumping the waste, oil pollution and shipment.

Quest. Mention the sources of soil pollution. 

Domestic wastes include garbage, rubbish material like:

1. glass, plastics, metallic cans, paper,
2. fibers, cloth bags, containers, paints, varnishes etc.

Quest. Define the greenhouse effect. 

The greenhouse effect, is a naturally occurring process that makes the earth warmer by trapping more energy in the atmosphere. The green house gases absorb and hold heat f om the sun, preventing it from escaping back into the space; much like a green house absorbs and holds the sun’s heat. Industrial wastes are the effluents discharged from chemical industries, paper and pulp mills, tanneries, textile mills, steel industries, distilleries, refineries, pesticides and fertilizer industries, pharmaceutical industries, food processing industries, cement industries, thermal and nuclear power plants, mining industries etc.

Quest. List the ozone-depleting chemicals. 

 ANSWER: Chlorofluorocarbons (CFC) are responsible for ozone layer depletion.

Quest. Define the term Noise Pollution.  

Noise pollution is the disturbing or excessive noise that may harm the activity or balance of human or animal life. The source of most outdoor noise worldwide is mainly caused by machines and transportation systems, motor vehicles, aircraft, and trains.

Quest. Define biological oxygen demand and chemical oxygen demand. Write its environmental impacts.  

Biological Oxygen Demand (BOD) is defined as the amount of DO required to aerobically decompose biodegradable organic matter over a period of 5 days at 20○C.
Chemical oxygen demand (COD) is commonly used to indirectly measure the amount of organic compounds in water.

Increase in BOD and COD values degrades the quality of water. It is harmful to aquatic organisms and causes toxic effects at various levels of food chain.

Quest. What are the effects of Global warming?  

a) More heat waves
b) Expansion of desert area
c) Natural fires in forestlands
d) More evaporation of water from oceans and water bodies
e) Melting of ice caps in Arctic and Antarctica regions
f) More cloud formation in the atmosphere.
g) Shorter and warmer winters and longer and shorter summer.
h) Changes in pattern of rainfall i) Rise in sea level

j) Flooding and submergence of low lying coastal areas

Quest. Give the effect of noise pollution on human beings. 

1. It causes contraction of blood vessels, makes the skin pale, leads to excessive secretion of adrenalin hormone in to blood stream which is responsible for high blood pressure.
2. It causes muscles to contract leading to nervous breakdown, tension etc.,

Quest. Define thermal pollution.

Thermal pollution is defined as the addition of excess of undesirable heat to water that makes it harmful to man, animal aquatic life otherwise causes significant departures from the normal activities of aquatic communities in water.

Quest. Mention the effects of solid waste.

Effects of solid waste.

1. Spreading of fungal diseases;
2. Bad odours;
3. Burning of waste produce chemicals which are harmful to human life;
4. Contaminates water &
5. Affects the characteristics of soil.

Quest. What are the damages caused by nuclear radiation?

Genetic damages – The damage is caused by radiations, which induce mutations in DNA. The damage is often seen in the offsprings and may be transmitted upto several generations.

Somatic damage – This includes burns, miscarriages, eye cataract, bone cancer etc.

Quest. Mention the activities involved in solid waste management.

1. Waste generation,
2. onsite handling, storage and processing
3. collection
4. transfer and transport
5. processing and recovery and disposal

Source:| NCERT | Wikipedia |

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