Environment, Sustainable Development and Disaster Management · Chapter 1

Ecosystems, Biodiversity and Conservation

What to remember

An ecosystem is a living community plus its non-living surroundings, linked by energy flow and nutrient cycling. Energy moves one way; nutrients move in cycles.
India has four of the 36 global biodiversity hotspots, and Andhra Pradesh holds parts of the Eastern Ghats, the Godavari-Krishna deltas, and the Seshachalam hills. Conservation is done in-situ (in nature) and ex-situ (outside nature).
Protected areas have different legal status: national parks have the strongest protection, sanctuaries allow some human activity, and biosphere reserves are zoned into core, buffer and transition areas.

Ecosystem concepts

An ecosystem has two parts. The biotic part has producers (green plants, algae), consumers (herbivores, carnivores, omnivores) and decomposers (bacteria, fungi). The abiotic part has sunlight, water, soil, air and temperature.

Ecosystems are grouped as:

Terrestrial: forest, grassland, desert, tundra.
Aquatic: freshwater (ponds, lakes, rivers, wetlands) and marine (oceans, estuaries, coral reefs, mangroves).
Artificial (man-made): crop fields, aquarium, reservoirs.

Ecotone is the transition zone between two ecosystems, such as a mangrove edge between land and sea. It often has more species than either neighbour. This is called the edge effect.

Productivity is the rate at which biomass is made. Primary productivity is made by producers. Gross primary productivity (GPP) minus plant respiration gives net primary productivity (NPP).

Food chains, food webs and pyramids

A food chain is a single line of feeding: grass, then grasshopper, then frog, then snake, then eagle. A food web is many food chains joined together. Webs are more stable than single chains.

Grazing food chain: begins with green plants.
Detritus food chain: begins with dead matter, eaten by decomposers and detritivores. In many ecosystems more energy flows through this chain than through the grazing chain.

Lindeman's ten percent law: only about 10 percent of energy passes from one trophic level to the next. The rest is lost as heat in respiration. That is why food chains have only four or five levels.

Pyramid	Shape in a grassland	Can it be inverted?
Number	Upright	Yes (one tree feeding many insects)
Biomass	Upright	Yes (in a pond, small producers, larger consumers)
Energy	Always upright	Never

Biomagnification is the rise in concentration of a persistent toxin (like DDT or mercury) at each higher trophic level.

Biodiversity

Biodiversity has three levels:

Genetic diversity: variation within a species (many rice varieties).
Species diversity: variety of species in an area.
Ecosystem diversity: variety of habitats in a region.

Biodiversity is usually higher near the equator and falls towards the poles. India is one of the mega-diverse countries.

Threats: habitat loss and fragmentation, poaching, invasive species, pollution, climate change and over-exploitation. The mnemonic is "HIPPO".

Biodiversity hotspot: an area with at least 1,500 species of endemic vascular plants that has lost at least 70 percent of its original habitat. Norman Myers proposed the idea in 1988. Conservation International later refined it.

India's hotspots: Himalaya, Indo-Burma, Western Ghats and Sri Lanka, and Sundaland (Nicobar Islands). The Eastern Ghats are not a hotspot, but are rich in endemic plants such as red sanders (*Pterocarpus santalinus*) in the Seshachalam and Nallamala hills.

Conservation

Type	Meaning	Examples
In-situ	Protecting species in their natural habitat	National parks, sanctuaries, biosphere reserves, sacred groves
Ex-situ	Protecting species outside their habitat	Zoos, botanical gardens, gene banks, seed banks, cryopreservation

Protected area categories in India (under the Wildlife (Protection) Act, 1972):

National park: no grazing, no private rights, boundaries fixed by law.
Wildlife sanctuary: limited human activity may be allowed.
Conservation reserve: government land next to parks or sanctuaries, declared by the State.
Community reserve: private or community land, declared with the community's consent.
Tiger reserve: notified under the Act after Project Tiger (1973), with core and buffer areas.

Biosphere reserves come under UNESCO's Man and Biosphere (MAB) programme. They have a core zone (strictly protected), a buffer zone (limited research and education) and a transition zone (people live and work). Their aim is conservation, development and logistic support.

Species programmes: Project Tiger (1973), Project Elephant (1992), and crocodile conservation projects. The Red Data Book of IUCN lists threatened species. Categories include Extinct, Critically Endangered, Endangered, Vulnerable, and Least Concern.

Andhra Pradesh protected areas

Nagarjunasagar-Srisailam Tiger Reserve: one of the largest tiger reserves in India by area. It covers the Nallamala forests near Srisailam. Gundla Brahmeswaram Wildlife Sanctuary lies in this landscape.
Sri Venkateswara National Park: in the Seshachalam hills near Tirupati and Tirumala. It protects rare plants and animals, with Talakona waterfall inside.
Papikonda National Park: along the Godavari gorge in the Eastern Ghats.
Seshachalam Hills Biosphere Reserve: notified as a biosphere reserve in 2010. It is the home of red sanders.
Coringa Wildlife Sanctuary: mangroves in the Godavari delta near Kakinada. It supports fishing cats and many water birds.
Krishna Wildlife Sanctuary: mangroves in the Krishna delta.
Kolleru Lake: a large freshwater lake between the Godavari and Krishna deltas. It is a wildlife sanctuary and a Ramsar site, famous for migratory birds such as pelicans.
Pulicat Lake: a large brackish water lagoon shared with Tamil Nadu. India's largest lagoon is Chilika in Odisha.
Nelapattu Bird Sanctuary: a pelican and spoonbill nesting site.
Rollapadu Wildlife Sanctuary: known for the great Indian bustard.
Kambalakonda Wildlife Sanctuary: a forest sanctuary near Visakhapatnam.

Mangroves: salt-tolerant trees with stilt roots and pneumatophores (breathing roots). They protect coasts from storms and are nurseries for fish and prawns. In AP they are found mainly in the Godavari and Krishna deltas.

Succession, nutrient cycles and ecosystem services

Ecological succession is the slow, orderly change in the species of a community over time.

Primary succession starts on bare rock or new land with no soil. The first living things are pioneer species, such as lichens.
Secondary succession starts where soil already exists, for example after a fire or on abandoned farmland. It is faster.
The stable final stage is the climax community.

Nutrient (biogeochemical) cycles return elements to the living world. The carbon cycle moves carbon between air, plants, animals, soil and oceans. The nitrogen cycle uses nitrogen fixation (by Rhizobium in legume roots), nitrification, and denitrification. Nitrogen cannot be used by most plants directly from air. Phosphorus has no gas phase; it cycles through rocks, soil and water.

Ecosystem services are the benefits people get from nature:

Provisioning: food, timber, medicine, water.
Regulating: climate control, flood control, pollination.
Supporting: soil formation and nutrient cycling.
Cultural: recreation, sacred groves, tourism.

Extinction, endemism and local conservation

Endemic species live in one region only. Keystone species have a very large effect on their ecosystem compared with their numbers. Flagship species (like the tiger) are used to attract support for conservation. Indicator species show the health of a habitat.

Extinction is a natural process, but human action has made it much faster. Island species are most at risk, as are those with small ranges.

Sacred groves are patches of forest protected by local belief. They are a traditional in-situ conservation system found in many parts of India, including the Eastern Ghats region.

Wetlands act like kidneys of the landscape. They store floodwater, filter pollutants and give a home to migratory birds. India has many Ramsar sites, and Kolleru in Andhra Pradesh is one of them.

Man-wildlife conflict occurs when animals enter farms or villages. Responses include barriers, early warning, compensation, and safe corridors for elephants and tigers. Wildlife corridors are strips of habitat that link two protected areas.

Convention and management bodies in brief

IUCN (International Union for Conservation of Nature) publishes the Red List.
WWF works on species and habitat conservation.
Wildlife Institute of India (Dehradun) trains and researches.
National Tiger Conservation Authority oversees tiger reserves.

Exam traps

1. A food chain is one line; a food web is many chains joined.
2. Energy pyramid is never inverted; number and biomass pyramids can be.
3. National park (no human rights) is different from sanctuary (some activity allowed).
4. Hotspots are defined by endemic plants and habitat loss, not by size.
5. The Eastern Ghats are not a hotspot; the Western Ghats are.
6. Kolleru is a freshwater lake; Pulicat is a brackish lagoon.
7. Coringa mangroves are in the Godavari delta; Krishna sanctuary is in the Krishna delta.
8. In-situ means "on site"; zoos and seed banks are ex-situ.

One-liners

1. Producers are also called autotrophs.
2. Decomposers recycle nutrients to the soil.
3. About 10 percent of energy passes to the next trophic level.
4. Norman Myers introduced the hotspot concept in 1988.
5. Project Tiger began in 1973.
6. Project Elephant began in 1992.
7. The Wildlife (Protection) Act was passed in 1972.
8. Biosphere reserves have core, buffer and transition zones.
9. Seshachalam Hills is the biosphere reserve of Andhra Pradesh.
10. Mangroves have pneumatophores.
11. Kolleru is a Ramsar wetland.
12. Seed banks and gene banks are examples of ex-situ conservation.

Practice questions

Which part of an ecosystem is made up of decomposers?
1. The abiotic component
2. Only the producers
3. The climate
4. The biotic component
Answer
D. The biotic component
Bacteria and fungi are living, so they belong to the biotic part.
The transition zone between two ecosystems is called a(n)
1. biome
2. niche
3. ecotone
4. climax
Answer
C. ecotone
An ecotone lies between two ecosystems and often has high species richness.
About what share of energy passes from one trophic level to the next, according to Lindeman's law?
1. 10 percent
2. 50 percent
3. 25 percent
4. 1 percent
Answer
A. 10 percent
Most energy is lost as heat; only about a tenth is passed on.
Which ecological pyramid is always upright?
1. Pyramid of numbers in a tree ecosystem
2. Pyramid of energy
3. Pyramid of numbers
4. Pyramid of biomass in a pond
Answer
B. Pyramid of energy
Energy is lost at each level, so the energy pyramid cannot be inverted.
A food chain that begins with dead organic matter is called a
1. grazing food chain
2. parasitic food chain
3. detritus food chain
4. predator chain only
Answer
C. detritus food chain
Detritus chains start with dead matter eaten by decomposers and detritivores.
Which of the following is NOT a biodiversity hotspot of India?
1. Indo-Burma
2. Himalaya
3. Western Ghats and Sri Lanka
4. Eastern Ghats
Answer
D. Eastern Ghats
The Eastern Ghats are rich in endemic plants but are not one of the recognised hotspots.
The concept of biodiversity hotspots was first put forward by
1. Raymond Lindeman
2. Norman Myers
3. Arthur Tansley
4. Eugene Odum
Answer
B. Norman Myers
Myers introduced the idea in 1988.
A biodiversity hotspot must have lost at least what share of its original habitat?
1. 70 percent
2. 90 percent
3. 30 percent
4. 50 percent
Answer
A. 70 percent
The two criteria are 1,500 endemic vascular plants and 70 percent habitat loss.
Variation among the many varieties of rice is an example of
1. habitat diversity
2. species diversity
3. ecosystem diversity
4. genetic diversity
Answer
D. genetic diversity
Variation within a species is genetic diversity.
Zoos and botanical gardens are examples of
1. habitat restoration
2. in-situ conservation
3. ex-situ conservation
4. community reserves
Answer
C. ex-situ conservation
They protect species outside their natural habitat.
Which protected area category is declared on private or community land with the community's consent?
1. Community reserve
2. National park
3. Biosphere reserve
4. Tiger reserve
Answer
A. Community reserve
Community reserves are set up under the Wildlife (Protection) Act on community or private land.
In a biosphere reserve, which zone is strictly protected?
1. Buffer zone
2. Transition zone
3. Manipulation zone only
4. Core zone
Answer
D. Core zone
The core zone is kept free of disturbance.
Biosphere reserves in India come under which UNESCO programme?
1. Global Tiger Initiative
2. Man and Biosphere programme
3. World Heritage Programme
4. Ramsar Programme
Answer
B. Man and Biosphere programme
The MAB programme designates biosphere reserves.
Project Tiger was launched in
1. 2002
2. 1973
3. 1992
4. 1952
Answer
B. 1973
Project Tiger began in 1973; Project Elephant began in 1992.
Pneumatophores are special roots found in
1. desert plants
2. epiphytes
3. mangroves
4. climbing plants
Answer
C. mangroves
These breathing roots help mangroves get air in waterlogged mud.
Which is the biosphere reserve of Andhra Pradesh?
1. Seshachalam Hills
2. Nallamala Hills
3. Papikonda Hills
4. Araku Valley
Answer
A. Seshachalam Hills
Seshachalam Hills was notified as a biosphere reserve in 2010.
Coringa Wildlife Sanctuary is known for its
1. thorn scrub
2. alpine meadows
3. mangrove forests
4. dry deciduous teak
Answer
C. mangrove forests
Coringa has mangroves in the Godavari delta.
Which water body in Andhra Pradesh is a Ramsar site and a famous bird habitat?
1. Nagarjuna Sagar
2. Srisailam reservoir
3. Pulicat Lake
4. Kolleru Lake
Answer
D. Kolleru Lake
Kolleru is a Ramsar wetland between the Godavari and Krishna deltas.
Rollapadu Wildlife Sanctuary is best known for protecting the
1. great Indian bustard
2. Olive Ridley turtle
3. Bengal tiger
4. Indian rhinoceros
Answer
A. great Indian bustard
Rollapadu is a grassland habitat of the great Indian bustard.
Which Andhra Pradesh sanctuary is a nesting site of pelicans and spoonbills?
1. Rollapadu
2. Nelapattu
3. Gundla Brahmeswaram
4. Kambalakonda
Answer
B. Nelapattu
Nelapattu is a bird sanctuary known for pelicans and spoonbills.
Sri Venkateswara National Park lies in the
1. Araku hills
2. Papikonda hills
3. Seshachalam hills
4. Nallamala hills
Answer
C. Seshachalam hills
It is near Tirupati and Tirumala in the Seshachalam range.
Red sanders (Pterocarpus santalinus) is mainly associated with the
1. Seshachalam and Nallamala region
2. Konkan coast
3. Himalayan foothills
4. Godavari delta
Answer
A. Seshachalam and Nallamala region
Red sanders is endemic to parts of the Eastern Ghats in southern Andhra Pradesh.
Pulicat Lake is best described as a
1. glacial lake
2. freshwater oxbow lake
3. man-made reservoir
4. brackish water lagoon
Answer
D. brackish water lagoon
Pulicat is a coastal brackish lagoon shared with Tamil Nadu.
Which pyramid can be inverted in a tree ecosystem?
1. Pyramid of energy
2. Pyramid of heat
3. None of them
4. Pyramid of numbers
Answer
D. Pyramid of numbers
One large tree supports many insects, so the number pyramid is inverted.
A species whose loss changes an ecosystem far more than its numbers suggest is a
1. flagship species
2. keystone species
3. endemic species
4. pioneer species
Answer
B. keystone species
Keystone species have a disproportionately large effect.
Which of these is a pioneer species in primary succession on bare rock?
1. Lichens
2. Oak trees
3. Tigers
4. Sal trees
Answer
A. Lichens
Lichens colonise bare rock first.
Which statement describes secondary succession?
1. It begins on bare rock
2. It begins where soil already exists
3. It never reaches climax
4. It occurs only in water
Answer
B. It begins where soil already exists
After fire or farming, soil remains, so succession is faster.
Which nutrient cycle has no gas phase in the atmosphere?
1. Water cycle
2. Nitrogen cycle
3. Phosphorus cycle
4. Carbon cycle
Answer
C. Phosphorus cycle
Phosphorus moves through rocks, soil and water only.
Nitrogen fixation in legumes is done by
1. Nitrosomonas only
2. Rhizobium bacteria
3. Mycorrhizal fungi
4. Algae in soil only
Answer
B. Rhizobium bacteria
Rhizobium lives in root nodules and fixes atmospheric nitrogen.
Persistent toxins like DDT become more concentrated at higher trophic levels. This is called
1. bioremediation
2. eutrophication
3. succession
4. biomagnification
Answer
D. biomagnification
Biomagnification increases concentration up the food chain.
A wildlife corridor is meant to
1. collect tourist fees
2. fence a national park
3. link two protected habitats
4. grow timber
Answer
C. link two protected habitats
Corridors let animals move between habitats.
Consider the statements: 1. In a national park, grazing and private rights are generally not allowed. 2. A wildlife sanctuary has stronger protection than a national park. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
A. 1 only
National parks are more strictly protected; sanctuaries may allow limited activity.
Consider the statements: 1. Energy flows in a cycle in an ecosystem. 2. Nutrients move in cycles in an ecosystem. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
B. 2 only
Energy flows one way; nutrients cycle.
Consider the statements: 1. Mangroves protect coasts from storms. 2. Mangroves are found only in freshwater. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
A. 1 only
Mangroves are salt-tolerant and live in coastal tidal areas.
Consider the statements: 1. Kolleru is a Ramsar wetland. 2. Pulicat is a freshwater lake. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
A. 1 only
Kolleru is a Ramsar site; Pulicat is a brackish lagoon.
Consider the statements: 1. The Seshachalam Hills is a biosphere reserve in Andhra Pradesh. 2. Coringa sanctuary protects mangroves in the Godavari delta. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
C. Both 1 and 2
Both statements are correct.
Consider the statements: 1. Biodiversity hotspots are identified only by their area. 2. Hotspots need high plant endemism and heavy habitat loss. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
B. 2 only
Hotspots are defined by endemism and habitat loss, not size.
Consider the statements: 1. Seed banks are in-situ conservation. 2. Sacred groves are traditional in-situ conservation. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
B. 2 only
Seed banks are ex-situ; sacred groves are in-situ.
Consider the statements: 1. The Wildlife (Protection) Act was passed in 1972. 2. Project Elephant was launched before Project Tiger. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
A. 1 only
Project Tiger was in 1973 and Project Elephant in 1992.
Consider the statements: 1. Net primary productivity is gross primary productivity minus plant respiration. 2. Decomposers are part of the abiotic component. Which of the statements is/are correct?
1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2
Answer
A. 1 only
Decomposers are living organisms, so they are biotic.
Match the sanctuary with its feature. 1. Coringa 2. Rollapadu 3. Nelapattu 4. Kolleru A. Great Indian bustard B. Pelicans C. Mangroves D. Freshwater lake
1. 1-A, 2-C, 3-B, 4-D
2. 1-D, 2-A, 3-B, 4-C
3. 1-C, 2-B, 3-A, 4-D
4. 1-C, 2-A, 3-B, 4-D
Answer
D. 1-C, 2-A, 3-B, 4-D
Coringa has mangroves, Rollapadu has bustards, Nelapattu has pelicans, Kolleru is a lake.
Match the term with its meaning. 1. Endemic 2. Flagship 3. Indicator 4. Keystone A. Reveals habitat health B. Found in only one region C. Rallies support for conservation D. Strong effect on ecosystem
1. 1-C, 2-B, 3-A, 4-D
2. 1-B, 2-A, 3-C, 4-D
3. 1-B, 2-C, 3-A, 4-D
4. 1-D, 2-C, 3-A, 4-B
Answer
C. 1-B, 2-C, 3-A, 4-D
Each term was matched with its standard meaning.
The edge effect refers to
1. energy loss in food chains
2. fewer species at habitat borders
3. poaching at park borders
4. greater species variety at an ecotone
Answer
D. greater species variety at an ecotone
Edge zones often have more species because two communities overlap.
Which type of ecosystem is a crop field?
1. Natural aquatic ecosystem
2. Grassland biome
3. Artificial ecosystem
4. Desert ecosystem
Answer
C. Artificial ecosystem
Crop fields are made and managed by people.
Gundla Brahmeswaram Wildlife Sanctuary lies in the landscape of the
1. Pulicat lagoon
2. Godavari delta
3. Papikonda hills
4. Nallamala forests
Answer
D. Nallamala forests
It is in the Nallamala forest area linked with the Nagarjunasagar-Srisailam Tiger Reserve.

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