(d) Both A and R are incorrect.

(b) A is incorrect R is correct.

(c) R explains A.

(a) Chlorella
(b) Scenedesmus
(c) Chroococcus
(d) Chlamydomonas

Chipko Movement and Appiko Movement

A non-native species to the ecosystem or country under consideration that spreads naturally, interferes with the biology and existence of native species, poses a serious threat to the ecosystem and causes economic loss.
e.g., Eichhornia crassipes

Deforestation	Afforestation
The conversion of the forested area into a non-forested area is known as deforestation	Afforestation is a planting of trees where there was no previous tree coverage and the conversion of non- forested lands into forests by planting suitable trees to retrieve the vegetation.

Social forestry refers to the management of forests and afforestation on barren lands with the purpose of helping the environmental, social and rural development and benefits.

Agroforestry is an integration of trees, crops, and livestock on the named plot of land. The commercial Agroforestry trees are casuarina and Eucalyptus.

The International treaty called the Montreal Protocol (1987) was held in Canada on substances that deplete ozone layer and the main goal of it is gradually eliminating the production and consumption of ozone depleting substances and to limit their damage on the Earth's ozone layer.

Man-made sources include nylon and nitric acid production, use of fertilizers in agriculture, manures cars with catalytic converter and burning of organic matter.

CO₂, CH₄, N₂O and CFC

Casuarina, Eucalyptus, Teak, Malai vembu.

(a) Increased global warming.
(b) Loss of livelihood for forest dwellers.
(c) Loss of bio-diversity
(d) Decrease in soil fertility.
(e) Decline in annual rainfall.

(a) Cloth / Jute bags
(b) Plantain leaves, palmyra plates as plates
(c) Metal cups
(d) Earthen pots or ceramic wares
(e) Paper made flags

The act of observing and assessing the current state and ongoing changes in ecosystem, biodiversity components, landscape including natural habitats, populations and species. An agricultural drone is an unmanned aerial vehicle applied to farming in order to help increased crop production and monitor crop growth. Agricultural drones let farmers see their fields from the sky. This bird’s eye-view can reveal many issues such as irrigation problems, soil variation and pest and fungal infestations. It is also used for cost effective safe method of spraying pesticides and fertilizers, which proves very easy and non-harmful.

Lakes as storage of rainwater provide drinking water, improves groundwater level and preserve the fresh water bio-diversity and habitat of the area wherein occurs.
In terms of services, lakes offer sustainable solutions to key issues of water management and climatic influences and benefits like nutrient retention, influencing local rainfall, removal of pollutants, phosphorous and nitrogen and carbon sequestration.

In-situ conservation means conservation and management of genetic resources in their natural habitats. Here the plant or animal species are protected within the existing habitat. Forest trees, medicinal and aromatic plants under threat are conserved by this method. This is carried out by the community or by the State conservation which includes wildlife, National park, and Biosphere reserve. The ecologically unique and biodiversity-rich regions are legally protected as wildlife sanctuaries, National parks and Biosphere reserves. Megamalai, Sathyamangalam wildlife, Guindy and Periyar National park, and Western Ghats, Nilgiris, Agasthyamalai, and Gulf of Mannar are the biosphere reserves of Tamil Nadu.

Chipko Movement:
The tribal women of Himalayas protested 'against the exploitation of forests in 1972. Later on, it transformed into Chipko Movement by Sundarlal Bahuguna in Mandal village of Chamoli district in 1974. People protested by hugging trees together which were felled by a sports goods company. Main features of Chipko movement were,
(i) This movement remained nonpolitical
(ii) It was a voluntary movement based on Gandhian thought.
(iii) It was concerned with the ecological balance of nature
(iv) Main aim of Chipko movement was to give a slogan of five F's - Food, Fodder, Fuel, Fibre and Fertilizer, to make the communities self-sufficient in all their basic needs.

Prosopis juliflora is used to arrest wind erosion and stabilize sand dunes on coastal and desert areas. It can absorb hazardous chemicals from soil and it is the main source of charcoal.

Clean Development Mechanism (CDM) is defined in the Kyoto protocol (2007) which provides project-based mechanisms with two objectives to prevent dangerous climate change and to reduce greenhouse gas emissions. CDM projects help countries to reduce or limit emissions and stimulate sustainable development.
An example of CDM project activity is the replacement of conventional electrification projects with solar panels or other energy efficient boilers. Such projects can earn Certified Emission Reduction (CER) with credits/scores, each equivalent to one tonne of CO₂, which can be counted towards meeting Kyoto targets

(i) Coal based power plants, by the burning of fossil fuels for electricity generation.
(ii) Combustion of fuels in the engines of automobiles, commercial vehicles, and air planes contribute the most of global warming.
(iii) Agricultural practices like stubble burning result in emission of CO₂.

(i) Rise in global temperature which causes sea levels to rise as polar ice caps and glaciers begin to melt causing submergence of many coastal cities in many parts of the world.
(ii) There will be a drastic change in weather patterns bringing more floods or droughts in some areas.
(iii) Biological diversity may get modified, some species ranges get redefined. Tropics and sub-tropics may face the problem of decreased food production.

Most abundant gas - CO₂
Effect of CO₂ on the growth of plants
(i) Change in flowering seasons and pollinators
(ii) Change in Species distributional ranges
(iii) Species extinction
(iv) Low agricultural productivity in tropics
(v) Frequent heat waves (Weeds, pests, fungi need warmer temperature)
(vi) Increase of vectors and epidemics
(vii) Strong storms and intense flood damage
(viii) Water crisis and decreased irrigation

Every human activity leaves a mark just like our footprint. This Carbon footprint is the total amount of greenhouse gases produced by human activities such as agriculture, industries, deforestation, waste disposal, burning fossil fuels directly or indirectly. It can be measured for an individual, family, organization like industries, state level or national level. It is usually estimated and expressed in equivalent tons of CO₂ per year. The burning of fossil fuels releases CO₂ and other greenhouse gases. In turn, these emissions trap solar energy and thus increase the global temperature resulting in ice melting, submerging of low lying areas and imbalance in nature Iike cyclones, tsunamis, and extreme weather conditions. To reduce the carbon footprint we can follow some practices like
(i) Eating indigenous fruits and products
(ii) Reduce use of your electronic devices
(iii) Reduce traveling
(iv) Do not buy fast and preserved, processed, packed foods.
(v) Plant a garden
(vi) Less consumption of meat and seafood. Poultry requires little space, nutrients and less pollution comparing cattle farming.
(vii) reduce the use of Laptops (when used for 8 hours, it releases nearly 2 kg. of CO₂ annually)
(viii) Line dry your clothes. (Example: If you buy imported fruit like kiwi, indirectly it increases CFP. How? The fruit has traveled a long distance in shipping or airliner thus emitting tons of CO₂)

Eichhornia crassipes is an invasive weed native to South America. It was introduced as aquatic ornamental plant, which grows faster throughout the year. Its widespread growth is a major cause of biodiversity loss worldwide. It affects the growth of phytoplankton and finally changing the aquatic ecosystem.
It also decreases the oxygen content of the waterbodies which leads to eutrophication. It poses a threat to human health because it creates a breeding habitat for disease-causing mosquitoes (particularly Anopheles) and snails with its free-floating dense roots and semi submerged leaves. It also blocks sunlight entering deep and the water ways hampering agriculture, fisheries, recreation, and hydropower.

Afforestation Objectives:
(i) To increase forest cover, planting more trees, increases CO₂ production and air quality.
(ii) Rehabilitation of degraded forests to increase carbon fixation and reducing CO₂ from atmosphere.
(iii) Raising bamboo plantations.
(iv) Mixed plantations of minor forest produce and medicinal plants.
(v) Regeneration of indigenous herbs/shrubs.
(vi) Awareness creation, monitoring, and evaluation.
(vii) To increase the level and availability of water table or ground water and also to reduce nitrogen leaching in soil and nitrogen contamination of drinking water, thus making it pure not polluted with nitrogen.
(viii) Nature aided artificial regeneration.

Effects of deforestation:
(i) Burning of forest wood release stored carbon, a negative impact just opposite of carbon sequestration,
(ii) Trees and plants bind the soil particles. The removal of forest cover increases soil erosion and decreases soil fertility. Deforestation in dry areas leads to the formation of deserts.
(iii) The amount of runoff water increases soil erosion and also creates flash flooding, thus reducing moisture and humidity.
(iv) The alteration of local precipitation patterns leading to drought conditions in many regions. It triggers adverse climatic conditions and alters water cycle in the ecosystem.
(v) It decreases the bio-diversity significantly as their habitats are disturbed and disruption of natural cycles.
(vi) Loss of livelihood for forest dwellers and rural people.
(vii) Increased global warming and account for one-third of total CO₂ emission.
(viii) Loss of life support resources, fuel, medicinal herbs, and wild edible fruits.
Benefits of agroforestry:
(i) It is an answer to the problem of soil and water conservation and also to stabilize the soil (salinity and water table) reduce landslide and water run-off problem.
(ii) Nutrient cycling between species improves and organic matter is maintained.
(iii) Trees provide a micro climate for crops and maintain O₂ - CO₂ balanced, atmospheric temperature and relative humidity.
(iv) Suitable for dry land where rainfall is minimum and hence it is a good system for alternate land use pattern.
(v) Multipurpose tree varieties like Acacia are used for wood pulp, tanning, paper, and firewood industries.
(vi) Agroforestry is recommended for the following purposes. It can be used as Farm Forestry for the extension of forests, mixed forestry, shelterbelts, and linear strip plantation.

Afforestation is planting of trees where there was no previous tree coverage and the conversion of non-forested lands into forests by planting suitable trees to retrieve the vegetation. Example: Slopes of dams afforested to reduce water run-off, erosion and siltation. It can also provide a range of environmental services including carbon sequestration, water retention.
The Man who Single handedly Created a Dense Forest
(i) Jadav "Molai" Payeng (born 1963) is an environmental activist has single-handedly planted a forest in the middle of a barren wasteland.
(ii) This Forest Man of India has transformed the world's largest river island, Majuli, located on one of India's major rivers, the Brahmaputra, into a dense forest, home to rhinos, deers, elephants, tigers, and birds.
(iii) And today his forest is larger than CentraI Park.

Rain Water Harvesting - RWH (Solution to water crisis - A ecological problem)
Rainwater harvesting is the accumulation and storage of rainwater for reuse in-site rather than allowing it to run off.
Rainwater can be collected from rivers, rooftops and the water collected is directed to a deep pit.
The water percolates and gets stored in the pit.
RWH is a sustainable water management practice implemented not only in the urban area but also in agricultural fields, which is an important economic cost-effective method for the future.


Environmental benefits of Rain Water Harvesting:
(i) Promotes adequacy of underground water and water conservation.
(ii) Mitigates the effect of drought.
(iii) Reduces soil erosion as surface run-off is reduced.
(iv) Reduces flood hazards.
(v) Improves groundwater quality and water table / decreases salinity.
(vi) No land is wasted for storage purpose and no population displacement is involved.
(vii) Storing water underground is an eco- friendly measure and a part of sustainable water storage strategy for local communities.