Ecosystem - Material


ECOSYSTEM

 Note: This material is designed and developed by Mr Ramesh, an eminent faculty member from Hyderabad. I express my gratitude for his contributions.

 N. Kalyana Chakravarthy  
     
The term ecosystem was coined by Roy Clapham-1930 and was used by Arthur.G.Tansley-1935 (British ecologists).

·         It was derived from Greek word “oikos- house”. Ecology- house -keeping.

·         DEFINATION: It is a dynamic complex- the study of earth’s house- holds including the plants, the animals, the microbes and the people that live together as intermediate components. (or)

·         The totality of patterns of relations between organisms and environment.


·         ECOLOGY: The scientific study of the relations that living organisms have with respect to each other and their natural environment.

                     OIKOS- House

                      LOGOS-study:        ecology-oekologie
·         In other words ecology simply means the study of house or the place where we are living.
·  
       Ecology is the interdisciplinary field that includes biology and the earth sciences.

·         Ancient Greek philosophers such as Hippocrates and Aristotle laid the foundations of ecology.
·         The word ecology was coined by German scientists ‘Ernst Haeckel’ in 1866.

·         Ecology is not related to environment or environmental history, but is closely related to the evolutionary biology, genetics and ethology.

·         It is a scientific and objective study of animal behavior.

·         Claments in 1969 defined ecology as a science of communities.
·         The focus area of ecological studies is to understand the ecological functions and how they affect the biodiversity.

·         The scope of ecology has widened and now there are many practical applications of ecology in
-conservation biology

-wetland management

-natural resource management ( agro ecology-agriculture, forestry, agro forestry, fisheries)

-city planning (urban ecology)

-community health

-applied science

-human social interaction
·  
       Ecosystem maintains the biophysical feedback mechanism that modulate metabolic rates and evolutionary dynamics between biotic and abiotic components of planet.

·         Ecosystem sustain life supporting functions and produce natural capital through the regulation of

1.      Continental climate

2.      Global biochemical cycles

3.      Water filtration

4.      Soils

5.      Food

6.      Fibers

7.      Medicines and many other natural features of scientific, historical, economic and intrinsic value.

Basic Terminology of Ecology:

1 .BIOSPHERE: The earth ecosystem functioning together on a global scale is called biosphere. It is an amalgamation of all the areas of ecosystem of the earth where life exists.
Generally it is said that the life exists till the elevations of troposphere –average 14-18km above mean sea level, till the abyssal plain i.e to the deepest of the ocean bottom (11.02)

2. BIOME: It includes the total assemblage of the plant and the animal life interacting with the life layer ( biosphere). The green plants dominate the biomes because of the enormous biomass and the biomass are classified by the characteristic life form of the green plants with in it and accordingly 5 principal biomes have been identified on the earth surface.
Ex: Forest biome: with ample water and temperature

 Savannah biome: transmission between forest and grassland

 Grassland biome: moderate shortage of soil water and adequate heat

 Desert biome: extreme adequate heat

 Tundra biome: insufficient heat and water.

3. BIOTIC COMMUNITIES: These are the local associations of plants and animals that are interdependent and often found together i.e they represent a group of animals and plants or the individuals of different species inhabiting a geographical area.

4.POPULATION: A Group of animals belonging to the same species is called as the population i.e the individuals of the same species inhabiting in a geographical area together are called as population.

5. SPECIES: It is a group of organisms i.e the plants and the animals with similar genetic characteristics and they interbreed among themselves and produce fertile off-springs.
Every species is reproductively isolated from such other species and capable of interbreeding.

6.ECOTONE: It is a transitional zone between two different ecosystem, this zone consists of the living organisms from both adjoining biotic communities of its own.
The best natural ecotone can be the brackish water ecotone i.e the creek or the estuary, where we can find both the marine and also the fresh water living things.
Eco= house; tone=tension (Greek). These are places where ecologies are in tension ,Ecotone may be local or regional.

8.ECOLOGICAL NICHE: The status occupied by an organisms in an ecosystem is called Niche.  Ex: human beings are the consumers, plants are the producers.

DEFINATION: Niche is the set of biotic and abiotic conditions in which a species is able to persist and maintain stable population sizes- said 
by Evelyn Hutchinson.

8.ECOLOGICAL SUCCESSION: The biotic communities succeed one another on the way to stable end point referred to an ecological succession.

9. SERE: Serial community, the series of communities that follow one another on the way to stable end stage.

10.PRIMARY SUCCESSION: It is the second community which has taken over the virgin community.

11.PIONEER STAGE: It is the first stage of succession.

12. AUTOGENIC SUCCESSION: The series of communities, succeeding due to the action of plant and animal themselves.

13. CLIMAX: The last stable community at end point is called the climax community, but due the human intervention these communities are getting changed. Ex: teak overtaken by bamboo.
Henry Cowles-1899 wrote climax
Frederic Clements-1900 used the term to describe.



ECOSYSTEM:  
Ecosystem are habitats within the biomes that form an integrated whole and a dynamically responsive system having both physical and biological complexes (George Perkin Marsh -1864)
The totality of patterns of  relations between organisms and environment. Ecosystem is of 3 types

a)      Terrestrial ecosystem

b)      Aquatic ecosystem

c)      Artificial ecosystem( techno ecosystem)

a)TERRESTRIAL ECOSYSTEM: There are 5 principal types of terrestrial ecosystem present, they are
1.      FOREST BIOME: Includes all regions of forest , it is an assemblage of trees growing close together forming an layer of foliage that largely shades the ground.
Frontier forests are the ones which are not disturbed by the human activity, the forest biome often show stratification and they span a wide range of climates and latitudes from the equatorial climate to the boreal forests and 6 types of forests biome are identified.
a) equatorial forests
b) tropical rain forest
c) monsoonal rain forests
d) broad lea evergreen or temperate rainfall or laurel forests
e) mid latitude deciduous or summer green forests
f) needle leaf forests

2.      SAVANNAH BIOME: It consists of combination of trees and grasslands in various proportions, it appearance is like a park, single tree surrounded by the grasses and shrubs.
The crowns of the trees are flattened and the trunks with thick and rough bark. This is to resists the summer in fire.

Species: Acacia, Grotesque, baobab ( the axe beaker), elephant grass etc
In south Americas Savannah biome i.e campo cerrado, the trees are largely broad leaved and evergreen.

3.      GRASSLAND BIOME:  It consists of largely and entirely of herbs i.e grasses and grass like plants, the trees are almost totally absent.
Ex: North .America – Prairies

      South America- Pampas

      Europe- Steppes

      Africa-Veldts

      Australia- Downs

      New Zealand- Canterbury plains

      Hungary-Puztas

Prairies are the tall grasses

Steppes are the short grasses

In America short grasses are called buffalo grasses.

4.      DESERT BIOME: Large surface proportions are bare ground without any vegetation and it is exposed directly to the natural forces, although treeless but contains “scattered woody vegetation”. Desert biome is of 3 types.

a) Thorn tree semi-desert: it has long and hot dry season. Ex: Caatinga in NE Brazil, Dorn veldt in South Africa


b) Semi desert: it has xerophytic vegetation with poorly developed herbaceous layer. Ex: sage brush of southern rockies and colarado


c) Dry desert: with no important degree of ground cover. Ex: in Australia the desert alternatives with porcupine grass
In Mojave – sonorant desert plants are often tree like

ex: saguaro cactus, prickly pear, cactus, ocotillo, cuosote brush, smoke trees
In Sahara desert. EX: Stipa and tamarix these all the trees which maintain dormant state to survive.

5.      Tundra Biome: It also consists of grasses along with abundance of flowering herbs, dwarf shrubs, mosses and lichens. Its ground cover is spotty.
During summers the marshy conditions prevail due to permafrost conditions. The small plants in these areas are annuals, many species flower brightly in summer.
The number of animal species is very small.
EX: Caribou, Reindeer, Artic foxes and polar-bears are predators

Mosquitoes and flies are abundant in July and it is most uncomfortable for humans and other mammals.

The foggy tundra offers an ideal summer environment for many migratory birds.
Forests- ample soil water and heat

Savannah-transitional between forests and grasslands

Grassland-moderate shortage of soil water and adequate heat

Desert- extreme shortage of and water adequate heat
Tundra- insufficient heat


Tropical zone: palms and bananas
Sub- tropical zone– laurels and myrtles
Warm temperature- evergreen forests
Cold temperature- deciduous forests
Sub -arctic –zone of coniferous
Polar- zone of alpine shrubs mosses and lichens.
B) AQUATIC BIOME:  There are many kinds of aquatic ecosystem that differs with regard to all abiotic factors.

The aquatic ecosystem range from an open ocean to small temporary ponds, having fluctuation conditions of salinity, depth and temperature.
The adaption of aquatic ecosystem varies in diversity and degree. Some of them are exclusively aquatic and some are amphibious in nature.
Marine ecosystems are the largest aquatic ecosystem and they include

A) Oceans

B) Salt marsh

C) Inter tidal ecology

D) Estuaries


E) Lagoons

F) Mangroves


G) Coral reefs


H) Deep sea


I) Sea floor

The marine ecosystem cover 2/3rd of surface of earth, they are very important for overall health of both marine and terrestrial environment. They are most productive regions providing food and shelter.

The coral reefs shelter the highest levels of biodiversity in the world. Hence they are called as the rainforests of the tropical oceans. The marine ecosystem oceans contains 97% of the planet water and they generate 32% of the worlds net primarily production.

The marine ecosystem are distinguished by the presence of dissolved compounds specially salts.
FRESH WATER ECOSYSTEM: It is characterized by its low concentration of salts and mineral ions, and they constitute -0.09% of the planet water and they generate 3% of the world’s net primary production. They are of 3 types

1. The Lentic ecosystem: it literally means slow moving water but includes the lake and pond ecosystem., both are characterized by stagnant fresh water bodies and occur practically in every biome.

They also vary in their sizes from less than a hectare to thousands of hectares like Victoria(Africa), Superior(USA), Caspian sea(Central Asia)- these are lakes having rich accumulations of organic compounds called Eutrophic lakes; poor in nutrients  called oligotrophic lakes.

2.The lotic ecosystem: it literally means the rapidly moving water and includes the streams and rivers, both of the differ from each other in volumes of water they carry, the speed of flow, oxygen content, temperature, ph  value and other several physical and chemical conditions.
Even the phytoplankton and the zooplankton population varies.
3. Wetland ecosystem: It is a land area that is saturated with water either permanently or seasonally. The water found in wet land can be saltwater, freshwater, and brackish.
The main wetland type includes ‘swamps’, fogs, marshes, fens. Wetland plays a number of roles in the environment, principally
-water purification, flood control, shoreline stability.
The largest wetland in the world include the

·         Amazon river basin,

·         West Siberian plain

·         Pantanal (Brazil)

FUNCTIONS OF THE AQUATIC 

ECOSYSTEM:

·         They recycle the nutrient

·         They purify the water

·         They attenuate the floods

·         They recharge the ground water

·         They provide habitat for wildlife

·         They provide human recreation

The abiotic characteristics present are temperature, salinity and the flow or discharge and they are the auto and heterotrophs.

·         The salt tolerant organisms are called as Euryhalines. The salt intolerant organisms are called as Stenohaline.

MICRO ECOSYSTEM: They are also called as experimental ecosystems. These are the artificial, simplified ecosystems that are used to stimulate and predict the behavior of natural ecosystems under controlled conditions.


c) ARTIFICIAL AND MANMADE ECOSYSTEM: This include villages, plantations, parks, fishery tanks, aquarium and the agriculture lands.
Agriculture ecosystems are the most important ones.




INTERACTIONS
The interactions among different species of animals in an ecosystem are different. The major components of interactions that prevail in ecosystem are

1. PREDATION: This is a direct food relation between two species of animals; one is predator and capture which feeds on the prey.

2. SCAVENGING: The wolves, Jackals, Hyenas and vultures feed on other organisms which have died naturally or some left overs.

3. PARASITISM: This is a harmful association between two species, which results in the damage or harm to one and benefit to other species

4. SYMBIOSIS: This is a beneficial association where two species benefit from each another

5. COMMENSALISM: This is a relationship which involves struggle among the organisms of same species, where one is benefitted without harming the other.

6. COMPETITION: This is a relationship which involves struggle among the organisms of same species or among the organisms of different species.

7.PROTECTIVE INDEPENDENCE: In a biotic community trees and other plants hide and protect animals by providing shelter from enemies and hostile weather, many of them camouflage themselves to suit the environment.

8. MIMICRY: It is the superficial resemblance of one organism to another to escape itself from the adversities as being harmful which is not actually the case.

STAGES: All the ecosystems present in the world can be put under 3 stages or states in terms of changes with time.

1.GROWTH ECOSYSTEM: This is the ecosystem which is under the process of growing where the successions are still in process.

It is  represented as
 




And it is graphically represented as positive transient stage

2.BALANCED ECOSYSTEM: This is the ecosystem which has reached the balanced stage i.e it has attained the climax stage
 




3.AGENING ECOSYSTEM: This is the ecosystem which has achieved its climax stage and residing  back or dieing off, may be due the un-favourable circumstances of climate.

 



COMPONENTS:

Ecosystem consists of two components namely the abiotic and biotic components.

1.ABIOTIC COMPONENTS: They are non- living components present in the ecosystem, it is of 3 types

a)Inorganic components: They includes the substances like C, N, WATER, etc

b)Organic components: They include like protein, lipids, carbohydrates etc, they are essential for the origin of life. Organic components acts as a link between abiotic and biotic components.

c)Climatic components: They include the physical factors of climate like the temperature, rainfall, pressure conditions etc
These are the physical factors which are responsible for the survival for the living.

2. BIOTIC COMPONENTS:  They are the living components present in the ecosystem and are put under 2 groups.

a)Autotrophic components: These are self-nourishing components present i.e the plants, they are the producers. They fix the light energy and manufacturing the food materials from simple to inorganic substances with the help of chlorophyll

b)Heterotrophic components: Nourishing on others i.e the consumers, they utilize and decompose the complex materials synthesized by the autotrophs.
They are divided into 2 groups.

A)    MACROCONSUMERS: They depend directly or indirectly on producers, they mostly include the animals, which exhibit the zoo-trophic nutrition.
Based on the dietary habits they are of 3 types

(I)Primary Consumers: They are the herbivores animals which directly depends on the autotrophs. Ex: grasshopper, rabbit, cattle, elephant etc

(ii)Secondary Consumers: They are carnivores animals and eat the herbivores, since their food consists of primary consumers, they are called as secondary consumers. Ex: frogs, birds

(iii) Tertiary consumers: They are the consumers of third order, these are top class carnivores, the members of which are not killed and eaten by others.
They depend directly on both primary and secondary consumers. Ex: tigers, lions, sharks, whales etc

B)MICROCONSUMERS: They include the decomposers i.e the microbes like bacteria, fungi.
They are also called as the detritivores because they depend on dead biotic components.
These microorganisms breakdown the complex organic compounds present in the dead plants and animals into simpler substances. They play a very important role by releasing and recycling back the materials into the soil and atmosphere.
Decomposers  comprises a very large and diverse group of organisms which act at different level.

FUNCTIONS:
There are two great principles or laws of general ecology, which are applicable in all the ecosystems and are called as the functional aspects of ecosystem. They are except under extreme conditions, different ecosystems are often able to maintain the same level of productivity under different condition of temperature or other factors.
1.One way of energy flowThe energy flow can be better understood by the productivities of the ecosystems which are of two types
Sunàatmàtreesàleavesàherbivoresàcarnivoresàdecomposers.
   50lakhsà10lakhsà5lakhsà2000à200à40





1.Primary Productivity: The productivity of autotrophs i.e the producers is called as the primary production.
It includes the gross primary productivity of the ecosystem in the total amount of the organic substances prepared by the autotrophs minus the energy utilized by them during the metabolism and catabolism is known as NPP.
NPP=GPP-E

2. Secondary productivity: The productivity of heterotrophs i.e the consumers is called as the secondary productivity.
Net secondary productivity includes the gross secondary productivity i.e the total amount of organic substances utilized by the heterotrophs as food minus the energy utilized and the non-digested food i.e excreta
NSP=GSP-E-NDF
The total food utilized minus the energy spent and excreted is the actual net secondary productivity.

2.Circulation of materials: This is again driven by the flow of energy, the energy which is not utilized will be driving the hydrological cycle and powers the weather system, it is called as the “ energy lost in the transformation”.
As it is evident from the above diagram that the energy flow is unidirectional, this flows and moves along with the food chain from one tropic level to another.

The available energy at a given tropic level is always lesser than that which was available in the previous tropic levels. Hence it goes on decreasing from the producer  to decomposers.

The circulation of the materials in an ecosystem is a continuous process, it involves the cyclic flow of materials i.e the organic and inorganic components between living and non living environment.

The kind of exchange of nutrient materials between the living and non- living world is called as the cycling of matter or” biogeochemical cycles”. Which are mostly helped by the decomposers.

That’s how the different components of ecosystem are interdependent on each other.

TROPHIC LEVEL: The word derived from the GREEK word

     TROPH=FOOD OR FEEDING; 

LEVEL=STAGE

This is nutritional status occupied by the organisms in a food chain.

The ecosystem energy flow biomass and the number of organisms are represented by the pyramids with different trophic levels. The actual triangle is upright, but the pyramid for biomass is becoming reversed in nature.




BIO-GEO CHEMICAL CYCLES

The land of exchange of materials between the living and non -living worlds are called as boo geo chemical cycles or nutrient cycles. They are classified into 2 types

1.      Gaseous

2.      Sedimentary

For the gaseous cycles the reservoir of materials in the atmosphere or the water. There are four major elements in the living organisms which are predominantly gaseous are “carbon”,”Hydrogen”,”Nitrogen”&”oxygen”.



THE CARBON CYCLE:

This cycle is considered as the fars of life ,the carbon is present in all organic matters from fossil fuels to the complex molecules like DNA ribo nucleic acids.

There are 5 sources of carbon in the world.
      
I.            As the organic molecules of “ biosphere”
    II.            As the gaseous molecules carbon dioxide of “atmosphere”
 III.            As the organic matter in the soil
 IV.            In the “lithosphere” as the fossil fuels and in the form of sedimentary deposits as limestone, chalk etc
    V.            In the “hydrosphere” that is in the oceans as dissolved carbon dioxide and as calcium carbonate shells in the organisms.

       



                         
·         The carbon moves from atmosphere to plants- photosynthesis, i.e CO2 is pulled from air to make food.

·         The carbon moves from plants to animals – animal consumption, i.e through the food chain

·         A carbon moves from plants and animals to ground- decomposition, i.e after the death and decays as fossil fuels.

·         The carbon moves from living things to atmosphere, i.e through respiration

·         The carbon moves from fossil fuels to atmosphere, i.e through combustion

·         The carbon moves from atmosphere to oceans, i.e by sinking and depositions.
Since the industrial revolution the atmospheric CO2 levels have increased by over 30% i.e from 275 ppm in the early 1700 to 365 ppm in 2010, and it is estimated that by 2100 it could reach between 450 to 600 ppm.

This is because of the human interactions in the form of combustion of fossil fuels and by modification of ecosystems. The fossil fuels account for 65% of CO2 and deforestation accounts for 35% of additional CO2 formed in the atmosphere.


THE OXYGEN CYCLE:

All the living things need oxygen for generating of energy in cells. The plants mark the beginning of O2 CYCLE by the process of photosynthesis.i.e the plants breathe in CO2  and breathe out O2.
Animals form the other half of the O2 cycle, during their respiration. During nights plants consume and in day they release it.







                             
THE NITROGEN CYCLE:





The N2 is the essential constituents of the proteins and the nucleic acids, which forms the structural and the functional components of living organisms
The N2 of the atmosphere is not available for the organisms because N2 molecules is relatively inert, to be useful for plants and animals and it should first be converted into more useful forms such as the NH4, NO3 or organic N2 i.e urea.

There are  main processes which cycle N2 through the biosphere, atmosphere and geosphere are
       I.            NITROGEN FIXATION:(ammonification)

This is the process where N2 is converted into NH4 ion  and it is done by process of converting free nitrogen of atmosphere into compounds of nitrogen and done by 3 process.

(a)    Atmospheric fixation by lightening

(b)   Biological fixation by symbiotic relationship of some plants and animals with microbes ( rhizobium, anabaena, azollae, azotobactes)

(c)    Industrial fixation , where nitrogen and hydrogen air made to react with each other at high temperature and pressure

N2+3H2 ----à2NH3at 600c and further processed to form urea and ammonium nitrate

    II.            NITROGEN MINERALISATION:
The ammonium form is again converted into in organic nitrogen by the death and decay of the living things and the process is known as nitrogen mineralization.

Sometimes ammonium and nitrate are also formed during decay
 III.            NITRIFICATION:
The ammonia formed is converted into nitrates and the nitrites, the process of conversion  is called the nitrification.
The ammonia is acted upon by nitrifying bacteria, nitrosomanas,nitrobacteria and is changed to nitrates.


 IV.            DE-NITRIFICATION:

The nitrates and nitrites are converted into nitric  and the nitrous oxides, from where the free nitrogen is released back into atmosphere from the soil by the denitrifying bacteria like the pseudomonas and the Bacillus denitricans present in the soil and water logged condition.
This process of conversion of nitrate etc into nitrogen gas is called denitrification.

    V.            The ammonium form of nitrogen is quickly  incorporated into protein and the other organic compounds.
                 
The following steps are involved in the nitrogen cycle

·         Atmospheric nitrogen into soil by bacteria or the lightening- ammonification

·         The plants absorb the nitrates from the soil and convert them into proteins-assimilation

·         The animals consume plants and plant proteins are used for making animal proteins

·         Proteins of plants and animals are decomposed into ammonia by putrefying bacteria and fungi- ammonification

·         The ammonia is converted into nitrites to nitrates by nitrifying bacteria or nitro factor- nitrification

·         The nitrates of the soil are converted back into free nitrogen gas by denitrifying bacteria- denitrification

Approximately 140 million metric tones of nitrogen is added to the ecosystems every year. The human activities are altering the nitrogen cycle by

(a)    Adding nitrogen fertilizers

(b)   Combustion of fossil fuels

(c)    By the forest fires

(d)   By live- stock and ranching water

(e)    By disposal of sewage waste
For the sedimentary cycles the reservoir of the materials is the lithosphere and the involving minerals are phosphorous, Sulphur and the calcium etc


PHOSPHOROUS CYCLE:
The phosphorous is an essential nutrient for both the plants and animals because it is a part of DNA, RNA, ATP, ADP  and is also useful for strengthening of the bones and teeth.
It is the solvent of all the material cycles, the plants absorb it from the water and the soil, from them plants, they are available to the animals. When animals die, the decomposers release P into the soil again or sometimes into the oceans.
It is not soluble in water and hence when it enter the lakes and the oceans it turns into sedimentary rocks, to be released millions of years later.
The weathering starts the cycle again. The humans apply the phosphate fertilizers to the crops.





SULPHUR CYCLE:

It is a secondary element with calcium and magnesium, it is a component of couple of vitamins and it occurs in two amino acids like cysteine and methionine.

It is also called as important component of co-enzyme-A for cellular respiration. The chemoautrophic bacteria convert the elemental sulphur into sulphates.

2S+H2O+3O2-----à2H2SO4

This sulphates are transformed into a reduced state, the sulphidei.e H2S by sulphur bacteria. 

During the decomposition of animal protein, which is a source of sulphur, the bacteria removes sulphide group

During the anaerobic respiration H2s is oxidized to form H2 and S for release of energy. The volcanic eruptions and the hot springs also release S into atmosphere.


FOOD CHAIN:
The transfer of food energy from the source in plants through of organisms with repeated states of eating and being eaten is food chain. In the food chain always the green plants will occupy the first trophic level.






The sequence of eating and being eaten in an ecosystem is known as food chain.

All organisms living or  are potential foods for some other organisms and thus, there is essentially no waste in the functioning of a natural ecosystem.

Depending on its nutritional status, each organisms in an ecosystem is assigned a feeding on trophic level.

It is a dynamic part of ecosystem which facilitates the continuous flow of energy. The food chain are of two types.



1.      GRAZING FOOD CHAIN:

It states with the autotrophs i.e the grasses or the green plants, from them it goes through the herbivores and then finally culminates in carnivores.
2.      DETRITUS FOOD CHAIN:

It starts with dead organic matter which the detrivores and the decomposers consume.

The partially decomposed dead organic matter and even the decomposers are consumed by the detritivores and their predators.

The leaf fragments are eaten by saprotrophs( theyare the organisms which feed on dead organic matter)

Ex: leaf litterà algaeàcrabsàsmall carnivores fishàsmall carnivores fish –Mangrooves ecosystem

Dead organic matteràfungiàbacteria—Forest ecosystem.

The food chain is explained by “Y” shaped energy model flow by considering both the types of food chains.

Grasslandsàplants: 50% herbivores-predators, 50% detritus-predators

Mature forestsàplants: 10% herbivores- predators,90% detritus-predators.

Ecosystem have become particularly important politically since the CBD convention on biological diversity, which was ratified by 192 countries for the protection of ecosystems, natural habitats and maintenance of variable populations of species in natural surroundings.






BIODIVERSITY

It refers to the incredible variety of life found on our planet. Biodiversity is the shortened term for biological diversity.

It is an umbrella term used to describe the number of varieties and variability of living organisms in a given assemblage.

Biodiversity, therefore embraces the whole of life on the earth.

It is described as the totality of genes, species and ecosystems corresponding to 3 fundamentals and hierarchically related levels of biological organization.

The concept of biodiversity was introduced by W.G.Rosen in 1985 and was popularized by Manus and Norse.

The life on earth is so diverse that we really have no idea that how many species are there.
The estimates fall in between 15-30million species of plants and animals and only 1.5-1.8 million species have been identified majority of them are un-indentified. Out of 34known animal phyla, only one phylum lives exclusively on land, 14 of them in oceans and rest 19 are amphibians in nature.

Approximately 7,50,000 insects, 41,000 vertebrates, 2,50,000 plants are described.

Biodiversity is the focal point to our existence  because

We derive the food which was once wild and we rely on the wild to improve the domesticated ones.

We derive the medicines from plants and animals to develop new drugs for treatment of various diseases. The human civilization continued for several thousands of years, was on the herbal medicines and even now we are extracting the required chemical formulae from the plant species.

The biodiversity provides a vast gene pool and the genetic resources for increasing the vigor by hybridization. Change in the gene pool may cause the depletion of the species themselves by the pests and insect attack. Ex: rice

The natural ecosystems in the form of national parks and sanctuaries are providing recreation for the distressed souls.

By the study the biodiversity the conversation of the endangered species, the links in the food webs can be done. Which may make available of more bigger gene pool and more chances of human survival.

TYPES OF BIODIVERSITY:

 There are 4 types of bio-diversities identified.

1.BIOLOGICAL DIVERSITY: It means the full range of variety and variability with in and among the living organisms and the ecological complexes in which they occur. (or)  it is a variety of life and its processes in the ecosystems.

2.GENETIC DIVERSITY:

It refers to the variation of genes within the species.
Ex: 10,000’s of rice varieties present in India.

3.SPECIES DIVERSITY:
It is a variety and abundance of different types of organisms which inhabit a geographical area. It is the species richness of an area and it is also called as taxonomic diversity.

Ex: An island with two species of birds and one species of lizard has great taxonomic diversity than an island having 3 species of birds present.

4.  ECOSYSTEM DIVERSITY:

It includes the variety of habitats that occur in a region. It is harder to measure.

Ex: the grass land ecosystem, deserts, savannahs etc.

Newly even the Agro biodiversity and microbial diversity are added.

Since 2000, 53 new species of primates have been described.

Ex: Brazilian monkey, Mura’s saddle back tarrarin etc.
               



BIODIVERSITY VALUE:

The biodiversity has got 3 values namely.

ECOLOGICAL VALUE:

All living organisms are supported by the interactions among organisms and ecosystem. The loss of biodiversity makes ecosystem less stable and more vulnerable and also weakens its natural cycles.


ECONOMIC VALUE:


Everything we buy and sell originates from the natural world. Nature provides the raw materials which we need for survival.
At least 1650 known tropical forest plants have the potential to be grown as the vegetable crops. Nature is a source for many medicines etc.


CULTURAL VALUE:

Most people feel connected to nature, often the reasons are hard to explain. Some feel strong spiritual bond and others are inspired by its beauty.




BIODIVERSITY DIVISIONS:

The are 2 important divisions of biodiversity namely

ALPHA-DIVERSITY: ( or within the habitat diversity)
This refers to a group of organisms interacting and also competing for the same resources and sharing the same environment.

BETA DIVERSITY: ( or between habitat diversity)
This refers to a group of organisms living in different habitats, but interacting and competing for the same resources by encroaching into each other or different habitats.             


                                                   PATTERNS:

The patterns of diversities change in relation to space and time.

IN SPACE:

We know that species diversity declines with increasing distance from the equator and the rich biodiversity of tropics is due to
the tropics remained relatively undisturbed ( no frequent glaciations ), so it had a long evolutionary time for species diversification.

More solar energy means more productivity which indirectly contributes to more diversity.

More the variable the habitat, greater is the species diversity in that habitat.


IN TIME

SEASONAL PATTERN: Diversity of species will vary during different seasons of the year. Since, the birds  and animals have the different breeding seasons, migratory behavior etc.


SUCCESSIONAL PATTERN: After the disturbances of ( fire and agriculture ), the plants and animals begin to reoccupy the habitat.
In this process other species out compete the original inhabitants.


EVOLUTIONARY PATTERN: Around 225 mya and phyla stopped increasing. 66 mya, the new classes stopped increasing whereas the new orders, families, genera and species are going on increasing.


 LOSS OF BIODIVERSITY:

The loss of biodiversity is most fundamental, it is natural and also irreversible.

All the species have a finite span of existence, so species extinction is a natural process which occurs without human intervention.

It is beyond the doubt that extinctions caused by human are occurring at a faster rate and far exceeds the natural rate and far exceeds the natural rate.

The global convention on biological diversity of 1992 “ The Earth Summit”.

It has devised 10 policy fields causes for the loss of biodiversity and one of that is mankind, is destroying the natural heritage at an incredible speed.

The biodiversity is facing threats. There are 4 major causes for the loss of biodiversity.


HABITAT LOSS AND FRAGMENTATION:

One of the most cause for the extinction of plants and animals is habitat loss and fragmentation, it is due to the human activities like expansions of the habitations, construction of transportation arteries in the forests, diverting the channels of rivers etc.

Ex: the rainforests are once covered more than 14% of the land surface now it is decreased to 6%

So when large habitats are broken up into the smaller fragments, the birds and the animals requiring large territories are badly effected leading to the population decline.

Ex: Great Indian Bustard in MP, Gujarat & Rajasthan; loin failed macaque in Western ghats.

OVER-EXPLOITATION:

Humans have always depended on nature for food and shelter, but need turns to greed it leads to over exploitation of natural resources
Ex: several species got extinction in the past 500 years due to over exploitation like the pigeons, sea-cows etc.
Shrinking the biodiversity leads to more vulnerability to diseases and lesser adaptability to climatic change.



INTRODUCTION TO NEW SPECIES:

Among the major threats faced by the native plant and animal species is the one posed by the invasive alien species, its only the second to the habitat loss.

Ex: Alien aquatic weeds like water hyacinth, lantana and carrot grass
Illegally introduced catfishes and big head craps adversely affected the native weeds and fishes.
Accidental entry of silver crap into Govind sagar Dam, over shadowed the native catla and mahseer fish.
In 1859, a farmer in S. Australia imported a dozen pairs of wild European rabbits, which by 1995 reached every corner of the country.


CO-EXTINCTIONS:

When species become extinct, the plant and animal species associated with it also become extinct.
Ex: cutting of huge trees causes the mini diversity lost like the birds, the insects, the creepers and the shrubs - under its shade are all lost.
Apart from the above
The climate change is also significant threat to biodiversity, because it will alter the growth, the reproduction, and the host –pathogen relationships in both the plants and the animals.

The raising sea levels are already submerging some of the islands leading to rapid loss of biodiversity.
Unsustainable use of natural resources, climate change, inappropriate fire regimes, changes to aquatic environment and water flows.




 HOTSPOTS:

The regions with a significant reservoir of biodiversity, that is under threat from humans.

They are biologically rich areas with high diversity and large percentage of endemic species.

The concept of Hotspots was forwarded by British ecologists “Norman Myers” in 1988.The area to be qualified as a hotspot:

a)It should support 1500endemic plant species i.e 0.5% of the global total

b)It must have loot> 70% of its original habitat
Accordingly there are 34 hotspots scattered, which are representing around 1.4% of the land area, 44% of the plant species, 35% of all the terrestrial vertebrates.

4 of the hotspots are present in North and Central America, 4 in Europe and C. Asia, 5 in S. America, 8 in Africa, 13 in Asia pacific ( 2 in India: Indo-Burma and Western ghats-Srilanka)

The world wild life found as devised a conservation strategy to save the biodiversity hotspots

Global 200 is the list of eco regions identified by world wildlife fund as the priorities of conservation, and a total of 238 “G200” regions have been identified.
142 (60%) are terrestrial.
53 (22%) are fresh water.
43 (18%) are marine habitat types.



 CONSERVATION:

There are many reasons for biodiversity conservation which are grouped into 3 categories

NARROWLY UTILITARIAN REASONS:
The narrowly utilitarian arguments for bio can are from the selfish point of view, humans should be concerned about saving biodiversity because of the benefits it provides us like biological resources and ecosystem services, the nature also provides the social and the spiritual benefits as well.
Biological resources; fall into several categories like food, medicines, fiber, wood products and more.

Ex: over 700 species of plants are used for food, although we heavily rely on only 12 major crops.
Ex: opiate pain relievers are from poppies
-aspirinàwillows
Quinineàchinchona
Rosy periwinkleàvinca rosea
Pacific yawàtexa bravifolia
Both provide substances used for inhabiting cell growth of cancerous cells.
Ex: shark skin provides the model for hydrodynamic swimming suites.
Glues used by sand castle worm, was the inspiration for the glue that mends the fractured bones. Spider silk to design a strong, lightweight fibers.
Ecosystem services: these are the processes provided by nature that support human life. The activities included are the decomposition of waste pollination, water purification, moderation of the floods and renewal of soil fertility,That the humans derive a countless economic benefits from nature, such as foods and products of medicinal importance.
Ex: 25% of the drugs of the world are derived from plants. 25000 species of plants contribute to traditional medicines.

Bio prospecting: exploring the molecular, genetic and species level products of economic importance from the living organisms called as bio prospecting.

The nations endowed with rich bio diversity can expect to reap enormous benefits.


BROADLY UTILITARIAN REASONS:

The broadly utilitarian argument says that the biodiversity plays major role for all.
Ex: amazon produce 20% of the total oxygen into earth’s atmosphere.

THE ETHICAL ARGUMENT:

 It is that because we share this planet along with millions of plants, animals and microbes etc. we owe and have moral duty to care for their wellbeing.
It is the philosophically or spiritually caused intrinsic values. Many biologists agree that we are in the midst of a mass extinction, the last great mass extinction was 65 million years.   ( when the dinosaurs went extinct at the end of the cretaceous period)
ICUN : The international union for the conservation of nature estimates that
22% of the known mammals
32% of the amphibians
14% of the birds and
32% of the gymnosperms are threatened with extinction.

The species that were abundant with in the last 200 years have gone extinct.

CONCLUSION: Pass our biological legacy in perfect order to our future generations.
The biodiversity conservation is accomplished in a number of ways, but are put under two broad headings

EX SITU METHODS:

Which focus on the species conservation in botanic gardens, zoos, gene banks and captive breeding programs.

It involves the conservation of the living organisms not in the site; that not in their natural habitat.

ZOOS: These contribute to the conservation of individual animal species, at present 90% of the critically endangered species are present in the zoos alone.

GENE BANKS: These are the store houses which are maintained under controlled temperature conditions, and in general the seeds of different species are stored.

Under such controlled conditions the preservation of seeds can be done for 100’s of years.

Ex: Svalbard seed vault (Norway) has got all known variety of seeds. àNational seeds bank is also established in Lehn.

BOTANIC GARDENS: These are also called as the field gene banks 1600 BG’s in world. Usually the plants that doesn’t produce seeds or the seeds which doesn’t germinate are conserved in the botanical gardens and the nurseries etc.

CAPTIVE BREEDING PROGRAM: The wild is very vast and the due to the depletion of species, there are no potent mates available for reproduction and the hence the animals are put together and are seen that they mate.

THE CRYO PRESERVATIONS: It includes the low temperature preservations, where the organs or the tissues are preserved in the liquid nitrogen at -172 c.


TISSUE CULTURE: This includes the growing of plants in the laboratories, may be in the test tube or conical flashes etc in the nutrient agar medium.

It is a type asexual reproduction, where the mass cloning of the single plant is multiplied either from the leaves or the stem etc.



IN SITU METHODS:
On the site, in the place which use the conservation areas as warehouses of biological information.

In situ methods are generally recognized as being more secure and financially efficient. The main conservation strategies includes
Expansion of the protected area network, in the form of national parks, sanctuaries and bio reserves etc.

This facilitates the gene flow through the creation of corridors, introduction of new genetic stock, translocation of the animals etc

Establishing minimum target population goals
Distributing founders through the captive breeding programs.

Improved protection efforts and landscape approach to conservation
Mapping the distribution of habitat type
Establishment of associating groups of species with different landscape elements.

Assessing the threats to the species because of on going commercial landscape changes.
Assigning conservation priorities to species on the basis of threats, rarity, endemism and taxonomic distinctiveness.
Assigning conservation priorities of different types of habitats etc.






  INDIAN BIODIVERSITY


India is the one of the 8 vavilovians centers ( origin of wild ancestors)

It ranks in top 10 species rich nations of the world.
India offers a wide range of habitat types with large variety of biodiversity.

According to IUCN of nature and natural resources, world conservation union, India has a total of 91,200 species of animals, 45,500  species of plants, à species of birds ( 9th in world); à500 species of mammals (7th in world);à 100’s species of reptiles(5th in world and is 47%);à 100’s of species of amphibians (7th in position its 61.2% of the world total)


Nearly 15% of the Indian biodiversity  is considered as “endemic” i.e these species are local and not found in other parts of the world.
The great problem faced by the biodiversity of India is that they are either 1. Getting endangered or2. In the stage of extinction.




ENDANGERED SPECIES:

The species whose life is threatened and known as endangered species.  Ex: Indian lion, snow leopard, wild buffalo, great Indian bustard, Nilghai, Niligiri Langur, Bengal tiger, Kashmiri stag, Musk deer, cheetah, wildars and the Gazelle etc


According to the Red data book of IUCN INDIA has 413 globally threatened species it is 4.9% of the world’s total.


The fast dwindling of the forest of western ghats and Himalayas etc , the human activities is adversely affecting the biodiversity and this trend is disturbing the ecological balance.



  RED DATA BOOK:

The IUCN is now called as the world conservation union, it has its headquarters at Morges, Switzerland is maintaining the “Red book data” or “red list”, which is a catalogue of taxa(species) facing risk of extinction.
The red book was initiated in 1963 to provide the

a)The awareness of threat to biodiversity

b)Provide a global index about already declined biodiversity

c)Guidelines for identification and documentation of species which are at high risk of extinction and for preparing conservation priorities and help in conservation action

d)To have the information about international agreements like convention on biological diversity CBD and the convention on international trade in endangered species of wild fauna and flora cities etc.

Red list 8 categories of species:

EXTINCT: The taxon which have been completely eliminated or died out from earth. Ex: dodo.dinasaurs

EXTINCT IN WILD: The taxon is absent in any of its natural or expected habitats in the wild. A number of domesticated animals and plants have become extinct in the wild.

CRITICALLY ENDANGERED: The taxon is facing very high risk of extinction in the wild and can become extinct in any moment in the immediate future.
Their number worldwide is 925 animals and 1014 plants (10%-mammals, 9%-birds, 15%-reptiles, 16%-amphibians, 16%- angiosperms). The number of critically endangered animals and plants in India is 18 and 44 respectively.
Ex: sus salvanius (pigmy, hog) berberis, nilghirienris, podo-phyllum etc

ENDANGERED: It is facing a high risk of extinction in the wild in the near future due to either

a)Decrease in its habitat

b)Excessive predation

c)Poaching etc

In India 54animals and 113 plants are endangered.
Ex: The Asiatic wild ass( asinus hemionus khur) restricted to Runn  of Kutch, the lion tailed macaque etc

VULNERABLE: Presently the population is sufficient, but if proper careis not taken they may undergo depletion.

Out of the total threatened species 34-51% are vulnerable with 34% mammals, 36% birds, 43% reptiles, 48% amphibians, 51% angiosperms.
In India their number is 143 animals and 87 plants. Ex: antelope cervicapra (black buck); cupressus cashmeriana- Indian gazelle etc


LOWER RISK: They are the threatened species which have lower risk of extinction, with less attention they become normal flourishing species

The percentage of lower risk species, out of the total threatened ones is 37% mammals, 38%-birds, 21% reptiles, 16%amphibians, 14% angiosperms. In India their number is 109 animals, 73 plant species.

DATA DEFICIENCY: The data for making direct and indirect assessment of risk of extinction is deficient.


NON EVALUTED: The taxon has not been evaluated for risk or extinction.


                                                  EFFORTS:

International efforts for conserving the biodiversity several, international agreements and global initiatives have focused on bio conservation like “ Earth summit” at Rio de Janerio 1992 Brazil promoted convention on biological diversity CBD”

UNESCO United nations educational scientific and cultural organization, in 1971 has began the man and the biosphere program aimed to improve relationship

The plan was to establish at least one (ideally 5 or more), biosphere reserves in each of the Earths 193 bio-geographical zones.

Convention concerning the protection of the world cultural and natural heritage, it was adopted by 
UNESCO 1972
It seeks to encourage the identification, protection and preservation of cultural and natural heritage. A number of sites in the heritage list are the nature parks, reservoirs etc, that conserve biodiversity.
RAMSAR: This is the convention for the protection of wet lands in Iran-1971
CITIES: Convention and international trade in endangered species wild fauna and flora has begun in 1975 with 21 countries.

But by 2010-175 signatories were present. This bans the hunting capturing and selling of the endangered or threatened species.

It lists over 900 species of live specimen or wild life products cannot be traded.
It restricts the international trade of 29000 other species that are potentially threatened.

UNCLOS: United nation’s convention on the law of the sea. This is to protect the marine biodiversity of accounting.
In 1980 three organizations, they are UNEP, ICUN, WWF

(a)UNEP: United nation’s environment program

(b)IUCN: International union for conservation of nature and natural resources

(c)WWF: World wild fund for nature have prepared a world conservation strategy.

The plan was to conserve biodiversity, preserve vital ecosystems and their processes and develop sustainable uses of organisms.

CBD: Convention on biological diversity was approved in 1992 at the Earth summit and came into force in 1993.

As on 2010 end 193 countries are parties to the convention. It has 3 goals

Conservation on biodiversity

Sustainable use of components of biodiversity
Nagoya program: It is on access to genetic resources and the fair and equitable sharing of benefits from their utilization, 29th,oct,2010
Sharing the benefits using from the commercial and other utilization of genetic resources in a fair and equitable way

It is the main international agreement for conserving global biodiversity because of the abundant diversity, conservation is important for not only for the country but also for the rest of the world and India is the secondary home for species.

CARTAGENA PROTOCOL: (On biosafety) this aims the safe handling of the bio aspects, while they are in transit, UN Nairobi office in 2000 with 166 signatories.( NGO- GREEN PEACE)

ICCMSB: International convention for the control and management of ships ballast water and sediments are adapted by 75 countries in 2004
Under this convention ships must have facilities to treat the ballast water before releasing them into foreign water.

NATIONAL EFFORTS FOR CONSERVATION:
India is a particularly and signatory country to all the major international conventions, the protocols and programs for conserving the biodiversity.
As soon as the idea was  mooted by UN, India actively participated and also brought out several acts for protecting biodiversity like:
National board for wild life 1952, for protection and conservation of wild life and to advice the government for constitution of national parks, sanctuaries and zoological gardens along with promoting public awareness

Under this board 99- national parks, 515 wild life sanctuaries, 53 tiger reserves, 18 biospheres, 19 zoological parks were been established.

Wild life protection act,1972: for conservation of wild life, protection of endangered species, breeding programs for endangered species, control of poaching and illegal trading of wildlife etc
Project tiger: it was launched in 1973 because the tiger population dwindled from 40,000 in the beginning of 20th century to just 1700 in 2010
There are 53 tiger reserves of which 17 are getting 100% cental assistance (largest Nagarjuna sagar).
National wildlife action plan: it was adopted in 1983. It provides framework and program for wildlife conservation

Project elephant was launched in 1992 and implemented in states and UT’S.
Wildlife crime control bureau-2008 was established.

Integrated forest protection scheme was introduced in 10th five year plan.
It has been renamed as the intensification of forest management in 11th five year plan, for conserving the uniue vegetation and ecosystem.
National biodiversity act came into effect from 2002.



 BIOSPHERE

The biosphere program is a part of international program, its idea was mooted by UNESCO in 1973-74

AIMS: For preserving the genetic diversity and integrity of all living organisms

To provide education on environmental awareness, for the initiation of ecological developmental process.

The 1st biosphere zone identified in India was Niligiris-1984, subsequently 17 more were added to the list and at present there are 18 biospheres in India, they are

Niligiri-                               1984 - TAMILNADU- 5500

Nokrek-                                 1988-  Meghalaya- 800
Nandadeir-                          1988 – UK- 5900
Great Nicobar-                                1989- A&N- 900
Gulf of mannar-                    1989- TN- 10500
Manas-                                       1989- ASSAM-2800
Sunderbans-                                  1989- WB- 9600
Simlipal-                                       1994- ORISSA- 4400
Dibru-saikhowa-                            1997- ASSAM- 770
Dehang – debang-                              1998- AR.P- 5100
Panmarhi or pach man –                      1999- MP- 4900
Kanchanjunga-                                  2000- SIKKIM- 2600
Agasthyamalai-                             2001- KERELA- 1800
Achanakamar-Amarkantak-                       20 05-MP-CHATTISGARH- 3800
Kutch-                                                2008- GUJARAT- 12500
Pin valley national park( cold desert)-                 2009- HP-
Seshachalam hills-                                             2010- AP-
Panna-                                                                    2011- MP
Each biosphere reserve has
a)Core and natural zone: no human activity
b)Buffer zone: limited human activity is allowed
c)Transition zone: it is also called manipulation zone. In this zone there is  active cooperation present between the local and forest officials for doing certain economic activities without disturbing ecology
The 1st protected area was the Hailey National park i.e.,JIM CORBETT National park which was established in 1935-36 in UK.
The biosphere is put under 3rd category of protected areas



MAN AND BIODIVERSITY PROGRAM:

It is an intergovernmental scientific program for the improvement of the relationship between the people and environment, launched in 1970 and began in 1971.

Till 2010 there were 562 biosphere reserves present in 109 countries.

4 of the India’s biospheres were included in the world network of biosphere reserves they areà Suderbans, Gulf of Mannar, Nilgiri, Nandadevi
4 more are considered for inclusionàManas, Simlipal, Pachmarhi, Kanchenzonga.