What’s it all about?

庫瑪 任

Prof. Ram Kumar

Department of Environmental Science

Central University of South Bihar

ecosystem.kumar@gmail.com

Online lecture (Sem-IV: MSc (2018-29: Biodiversity & Conservation Biology

BIODIVERSITY HOTSPOTS OF THE WORLD

Darwin as an Ecologist

Xanthopan

Angraecum sesquipedale

As one moves from the molecular

and cellular levels to higher levels

of biological organization, each

level reveals properties not evident

at the level below or predictable

from the properties at that level

Biosphere

Ecosystem

Communities

Species

Populations

Individuals

Organs

Tissues

Cells

Macromolecules

Ecologists are often interested,

not in the mechanisms (the

“How?” questions) leading to

a biological event or a process,

but in their significance and

impacts (the “Why?” questions)

at different levels of biological

organization.

Why?

How? Emergent Properties

Ecological organizations

Biomes-

Communities-

Species-

Populations-

individual organisms

• Major life zones characterized by vegetation type (terrestrial

biomes) or physical environment (aquatic biomes)

• Climate is very important in determining why terrestrial

biomes are found in certain areas Leads to formation of

tropical (hot), temperate (moderate) and polar (cold) regions –

deserts, grasslands and forests

A community (biocoenosis) is an assemblage of

populations of two or more different species occupying

the same geographical area and in a particular time.

The largest group of organisms capable of interbreeding and

producing fertile offspring.

The sum total of all the individuals of the same species,

who live in the same geographical area, and have the

capability of interbreeding.

“In the end, we will conserve only what we love,

We will love only what we understand,

We will understand only what we are taught” -Baba Dioum

Natural Capital: Major Components of

the Earth’s Biodiversity

Major terrestrial biomes of the

world

Land 30% of the Earth’s surface

• Climax community

form the matrix of the

biome

• Biome is names after

the climax community

Tundra Biome: Between Arctic ocean and polar ice.

Treeless plain of the Arctic region marshy during

summer and frozen hard during winter.

How thick should the polar bear’s fur be?

Too thin: Does not give enough warmth

Too thick: Increases body weight

Tundra Biome:

• Plant communities are usually composed

of a few species of dwarf shrubs, a few

grass species and Mosses.

• Lichens characteristic arctic tundra

plants are like Reindeer Moss (Cladonia

spp.).

• The principal herbivores in this biome

include caribou, musk ox, arctic hare,

voles, and lemmings.

Boreal coniferous forest

• Mammals, common to the boreal forest

include

moose, bear, deer, wolverine, marten,

lynx, wolf, snowshoe hare, vole,

chipmunks, shrews, and bats .

• Reptiles:

are rare, because of cold temperatures

.

Coniferous

Temperate deciduous

Temperate Deciduous Forest

• Moderate climate and deciduous trees.

• The eastern half of the United States, central Europe, Korea, and China.

• Very extensively affected by human activity, and much of it has been converted into agricultural fields or urban developments.

• Dominant plants include trees like Maple (Acer spp.), Beech (Fagus spp.), Oak (Quercus spp.), Hickory (Carya spp.), Basswood (Tilia spp.), Cottonwood (Populus spp.), Elm (Ulmus spp.), and Willow (Salix spp.). The understory of shrubs and herbs in a mature deciduous forest is typically well developed and richly diversified.

• Brown forest soils characterize temperate deciduous forest ecosystems.

• The surface (Litter layer) is thin due to rapid decomposition.

Grass lands

• Intermediate w forest & Deserts

• Prairies, Srteppes and Pampas

• Bison, Wildhorse, Squirrels, kagaroos, etc.

Grassland

• In central North America are the grass lands, the tall

grass prairie toward the east and the short grass prairie westward.

• In Europe and Asia some grasslands are called Steppes.

• In South America, grasslands are known as Pampas. Prior to modern man, the tall grass prairie was dominated by species of Bluestem (Andropogon spp.)

• Grassland mammals are dominated by smaller burrowing herbivores (prairie dogs, jack rabbits, ground squirrels, gophers) and larger running herbivores such as bison, pronghorn antelope, and elk.

• Carnivores: include badger, coyote, ferret, wolf, and cougar.

Chaparral

Mild, wet winters and hot dry

summers) and wildfire, featuring

summer drought-tolerant plants

with hard evergreen leaves,

• chaparro, Scrub Oaks,

Desert Gobi, Kalahari, Sahara, Thar

Savanna

Forest Biome

1. Tropical rain forest

2. Coniferous

3. Deciduous forest

Tropical rain forest

• The main areas of tropical

rain forest in India are

Andaman and nocobar; The

western Ghats, Asam region.

• Small region in Orissa .

• Semi ever green rain forest is

more extensive than the

evergreen formation

• Partly because evergreen

forests tend to degrade to

semi-evergreen with human

interference.

Tropical Rain foprest

"jewels of the Earth" and the “ World’s largest

pharmacy” It is likely that there may be many millions

of species of plants, insects and microorganisms

• A tropical rainforest is an ecosystem type that

occurs roughly : 28 degrees N / south of the equator

(in the equatorial zone between the Tropic of Cancer

and tropic of capricorn).

• High average temperatures and a significant amount of

rainfall.

• In Asia, Australia, Africa, South & Central America,

Mexico and on many of the Pacific Caribbean and

Indian Ocean islands.

Tropical Rain foprest

Tropical Rain foprest

• A/c to WWF’s biome classification, tropical rainforests are

thought to be a type of tropical wet forest (Tropical moist

broad leaf forest) also referred to as lowland equatorial

evergreen rainforest.

• Characterized in two words: warm and wet.

• Mean monthly temperatures exceed 18 °C (64 °F) during all

months of the year.

• Average annual rainfall is no less than 168 cm (66 in) and

can exceed 1,000 cm although it typically lies between

175 cm and 200 cm.

• This high level of precipitation often results in poor soils due

to leaching of soluble nutrients.

• Unique in the high levels of biodiversity.

• Around 40% to 75% of all biotic species are indeginous

to the rainforests.

• Rainforests are home to half of all the living animal and

plant species on the planet.

• Two-thirds of all flowering plants can be found in

rainforests.

• A single hectare of rainforest may contain 42,000

different species of insect, up to 807 trees of 313

species and 1,500 species of higher

Tropical Rain foprest

Coral reefs

• Sea anemones and corals : clade Anthozoa (flower

animals)

• Solitary or colonial forms

• Many species secret hard external skeleton of calcium

carbonate

• Coral reefs to tropical seas: rainforest to tropical land

• Habitat for many other species

• Sensitive to temperature; Optimum temp: 18-20 to 30°C

• Deep sea corals less known: 200-1,500m deep

Optimum Chemical environment for Corals

• Require High Oxygen levels

• Excluded by high inputs of freshwater and nutrients

Optimum Geologic features:

• Requires a solid substrate for attachment

• A typical coral reef begins as a fringing reef on a young,

-high island forming an offshore barrier reef later in

the history of the island and -becoming a coral atoll as

the older island submerges.

Coral reefs

Heterotrophs: Corals a diverse group of cnidarians, Very

high fish and invertebrate diversity’

Human impacts: • Collection of coral skeletons and overfishing reduce

populations of corals and reef fishes

• Global warming and pollution may be contributing to

large –scale coral death.

• Development of coastal mangroves for aquaculture

also reduced spawning grounds for many species of

reef fishes.

Autotrophs in Coral ecosystems: Unicellular algae

within coral tissues: mutualism, Multicellular red and green

algae, growing on the reef

Coral reefs

Mangrove ecosystems

• A special type of vegetation found in saline soils;

• Commonly found in estuarine delta and sea-coasts.

What is it?

• A tree or shrub (families Rhizophoraceae and

Verbenaceae /Avicenniaceae) that grows in muddy, chiefly

tropical coastal swamps,...

• A tidal swamp that is dominated by mangroves and

associated vegetation

Mangroves

• Mangroves are essentially the rainforest of the sea, and

are unique in both the plant and animal life they support.

• Mangroves are found practically in almost all the

continents, excepting Europe, the Arctic and Antarctic.

• Luxuriant patches of mangroves are found on all the other

continents but the best mangroves are found in Asia,

especially in India and Bangladesh - the Sunderbans are

the largest mangrove forest in the world both in size

as well as biodiversity

Ecological communities:

Requires following ecological conditions:

i. Shallow water

ii. Thick mud

iii. High rainfall

iv. High humidity and cloudy weather

v. Water logged saline soil/loose soil with large amount of

organic matter

Groups of tropical trees or shrubs that grow in swampy

ground along river banks, with branches that spread and send

down roots, thus forming more trunks and causing growth.

Mangroves in India

• The total area of mangroves in India is about 6,740 sq.

km, (~ 7% of the world's total area of mangroves).

• 80% are present along the east coast, mostly forming

the Sunderbans, Bhitarkanika and the Andaman &

Nicobar mangroves.

• The Gangetic Sunderbans is about 4,000 sq. km whereas

Andaman & Nicobar is about 700 sq km.

• Large rivers like Mahanadi, Krishna, Cauveri, Godavari also

harbour major mangroves in their estuarine regions.

The remaining 20% mangroves are scattered on the west coast from Kutch to Kerala.

Wetlands: Definition types and role