Ecology and its Principles/Ecological Succession
Ecology and its Principles Ecological Succession
Ecology and its Principles
Ecology is defined as a scientific study of the interaction of living organisms with each other and with their environment. It deals with the ways in which organism are surrounded by their environment, how they make use of environmental resources including energy flow and mineral cycling.
The study of ecology has presently contributed a lot to the socio-economic and political issues of the world as it plays an important role in agriculture, fishery, pest control, conservation of soil, forests and water resources. All the international issues of environment such as pollution and resource management need a sound knowledge of ecology. Ecology is a human science as well. 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, economics, basic and applied science, and human social interaction (human ecology).
The study of ecology has presently contributed a lot to the socio-economic and political issues of the world as it plays an important role in agriculture, fishery, pest control, conservation of soil, forests and water resources. All the international issues of environment such as pollution and resource management need a sound knowledge of ecology. Ecology is a human science as well. 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, economics, basic and applied science, and human social interaction (human ecology).
LEVELS OF ORGANIZATION
Ecologists study nature on different levels, from a local to a global scale. These levels reveal the complex relationships found in nature.
Ecologists study nature on different levels, from a local to a global scale. These levels reveal the complex relationships found in nature.
• Organism: An organism is an individual living thing, such as an alligator.
• Population: A population is a group of the same species that lives in one area, such as all the alligators that live in a swamp.
• Community: A community is a group of different species that live together in one area, such as groups of alligators, turtles, birds, fish, and plants that live together in the Florida Everglades.
• Ecosystem: An ecosystem includes all of the organisms as well as the climate, soil, water, rocks, and other nonliving things in a given area. Ecosystems can vary in size. An entire ecosystem may live within a decaying log, which in turn may be part of a larger wetland ecosystem.
• Biome: A biome (BY-ohm) is a major regional or global community of organisms. Biomes are usually characterized by the climate conditions and plant communities that thrive there. Ecologists study relationships within each level of organization and also between levels. For example, researchers may study the relationships within a population of alligators, as well as the relationships between alligators and turtles in a community.
• Population: A population is a group of the same species that lives in one area, such as all the alligators that live in a swamp.
• Community: A community is a group of different species that live together in one area, such as groups of alligators, turtles, birds, fish, and plants that live together in the Florida Everglades.
• Ecosystem: An ecosystem includes all of the organisms as well as the climate, soil, water, rocks, and other nonliving things in a given area. Ecosystems can vary in size. An entire ecosystem may live within a decaying log, which in turn may be part of a larger wetland ecosystem.
• Biome: A biome (BY-ohm) is a major regional or global community of organisms. Biomes are usually characterized by the climate conditions and plant communities that thrive there. Ecologists study relationships within each level of organization and also between levels. For example, researchers may study the relationships within a population of alligators, as well as the relationships between alligators and turtles in a community.
ECOLOGICAL PRINCIPLES
• Principle 1: Protection of species and species’ subdivisions will conserve genetic diversity.
At the population level, the important processes are ultimately genetic and evolutionary because these maintain the potential for continued existence of species and their adaptation to changing conditions. In most instances managing for genetic diversity directly is impractical and difficult to implement. The most credible surrogate for sustaining genetic variability is maintaining not only species but also the spatial structure of genetic variation within species (such as sub-species and populations). Maintenance of populations distributed across a species’ natural range will assist in conserving genetic variability. This ensures the continuation of locally adapted genetic variants. Retaining a variety of individuals and species permits the adaptability needed to sustain ecosystem productivity in changing environments and can also beget further diversity (future adaptability).
• Principle 1: Protection of species and species’ subdivisions will conserve genetic diversity.
At the population level, the important processes are ultimately genetic and evolutionary because these maintain the potential for continued existence of species and their adaptation to changing conditions. In most instances managing for genetic diversity directly is impractical and difficult to implement. The most credible surrogate for sustaining genetic variability is maintaining not only species but also the spatial structure of genetic variation within species (such as sub-species and populations). Maintenance of populations distributed across a species’ natural range will assist in conserving genetic variability. This ensures the continuation of locally adapted genetic variants. Retaining a variety of individuals and species permits the adaptability needed to sustain ecosystem productivity in changing environments and can also beget further diversity (future adaptability).
• Principle 2: Maintaining habitat is fundamental to conserving species.
A species habitat is the ecosystem conditions that support its life requirements. Habitat can be considered at a range of spatial and temporal scales that include specific microsites (e.g., occupied by certain invertebrates, bryophytes, some lichens), large heterogeneous habitats, or occupancy of habitat during certain time periods (e.g., breeding sites, winter range areas). Therefore conserving habitat requires a multi-scale approach from regions to landscapes to ecosystems to critical habitat elements, features and structures
A species habitat is the ecosystem conditions that support its life requirements. Habitat can be considered at a range of spatial and temporal scales that include specific microsites (e.g., occupied by certain invertebrates, bryophytes, some lichens), large heterogeneous habitats, or occupancy of habitat during certain time periods (e.g., breeding sites, winter range areas). Therefore conserving habitat requires a multi-scale approach from regions to landscapes to ecosystems to critical habitat elements, features and structures
• Principle 3: Large areas usually contain more species than smaller areas with similar habitat.
The theory of island biogeography illustrates a basic principle that large areas usually contain more species than smaller areas with similar habitat because they can support larger and more viable populations. The theory holds that the number of species on an island is determined by two factors: the distance from the mainland and island size. These would affect the rate of extinction on the islands and the level of immigration. Other factors being similar (including distance to the mainland), on smaller islands the chance of extinction is greater than on larger ones. This is one reason why larger islands can hold more species than smaller ones.
The theory of island biogeography illustrates a basic principle that large areas usually contain more species than smaller areas with similar habitat because they can support larger and more viable populations. The theory holds that the number of species on an island is determined by two factors: the distance from the mainland and island size. These would affect the rate of extinction on the islands and the level of immigration. Other factors being similar (including distance to the mainland), on smaller islands the chance of extinction is greater than on larger ones. This is one reason why larger islands can hold more species than smaller ones.
• Principle 4: All things are connected but the nature and strength of those connections vary
Species play many different roles in communities and ecosystems and are connected by those roles to other species in different ways and with varying degrees of strength. It is important to understand key interactions. Some species (e.g., keystone species) have a more profound effect on ecosystems than others. Particular species and networks of interacting species have key, broad-scale ecosystem-level effects while others do not. The ways in which species interact vary in addition to the strengths of those interactions. Species can be predator and/or prey, mutualist or synergist. Mutualist species provide a mutually beneficial association for each other such as fungi that colonize plant roots and aid in the uptake of soil mineral nutrients. Synergistic species create an effect greater than that predicted by the sum of effects each is able to create independently.
Species play many different roles in communities and ecosystems and are connected by those roles to other species in different ways and with varying degrees of strength. It is important to understand key interactions. Some species (e.g., keystone species) have a more profound effect on ecosystems than others. Particular species and networks of interacting species have key, broad-scale ecosystem-level effects while others do not. The ways in which species interact vary in addition to the strengths of those interactions. Species can be predator and/or prey, mutualist or synergist. Mutualist species provide a mutually beneficial association for each other such as fungi that colonize plant roots and aid in the uptake of soil mineral nutrients. Synergistic species create an effect greater than that predicted by the sum of effects each is able to create independently.
• Principle 5: Disturbances shape the characteristics of populations, communities, and ecosystems.
Natural disturbances have played a key role in forming and maintaining natural ecosystems by influencing their structure including the size, shape and distribution of patches. The more regions, landscapes, ecosystems and local habitat elements resemble those that were established from natural disturbances, the greater the probability that native species and ecological processes will be maintained. For example, high frequency, low intensity fires have shaped ponderosa pine ecosystems while low frequency, high intensity fires have shaped lodgepole pine ecosystems. Maintaining these ecosystems means restoring fire and/or designing management practices such as harvesting to reduce the differences between a managed landscape and a landscape pattern created by natural disturbance.
Natural disturbances have played a key role in forming and maintaining natural ecosystems by influencing their structure including the size, shape and distribution of patches. The more regions, landscapes, ecosystems and local habitat elements resemble those that were established from natural disturbances, the greater the probability that native species and ecological processes will be maintained. For example, high frequency, low intensity fires have shaped ponderosa pine ecosystems while low frequency, high intensity fires have shaped lodgepole pine ecosystems. Maintaining these ecosystems means restoring fire and/or designing management practices such as harvesting to reduce the differences between a managed landscape and a landscape pattern created by natural disturbance.
• Principle 6: Climate influences terrestrial, freshwater and marine ecosystems.
Climate is usually defined as all of the states of the atmosphere seen at a place over many years. Climate has a dominant effect on biodiversity as it influences meteorological variables like temperature, precipitation and wind with consequences for many ecological and physical processes, such as photosynthesis and fire behaviour. Because of the key role of climate, rapid climate change profoundly changes ecosystems.
Climate is usually defined as all of the states of the atmosphere seen at a place over many years. Climate has a dominant effect on biodiversity as it influences meteorological variables like temperature, precipitation and wind with consequences for many ecological and physical processes, such as photosynthesis and fire behaviour. Because of the key role of climate, rapid climate change profoundly changes ecosystems.
OTHER TERMS ASSOCIATED WITH ECOLOGY
a) Habitat: Habitat is the physical environment in which an organism lives. Each organism has particular requirements for its survival and lives where the environment provides for those needs. The features of the habitat can be represented by its structural components namely (1) space (2) food (3) water (4) and cover or shelter.
a) Habitat: Habitat is the physical environment in which an organism lives. Each organism has particular requirements for its survival and lives where the environment provides for those needs. The features of the habitat can be represented by its structural components namely (1) space (2) food (3) water (4) and cover or shelter.
b) Niche: The term niche means the sum of all the activities and relationships of a species by which it uses the resources in its habitat for its survival and reproduction.
c) Species: A species is defined as; “a group of similar populations of organisms whose members are capable of interbreeding, and to produce fertile offspring (children)”. A tiger, a lion, a lotus and a rose are examples of different species.
d) Speciation: Speciation is the process by which new species are formed and evolution is the mechanism by which speciation is brought about.
Indus Valley Civilization Sites/Harrapan Culture
Indus Valley Civilization Sites Harrapan Culture
Indus Valley Civilization Sites
• The earliest excavations in the Indus valley were done at Harappa in the West Punjab and Mohenjodaro in Sind.
• Both places are now in Pakistan.
• The findings in these two cities brought to light a civilization which was first called the ‘The Indus Valley Civilization’.
• But this civilization was later named as the ‘Indus Civilization’ due to the discovery of more and more sites far away from the Indus valley.
• Also, it has come to be called the ‘Harappan Civilization’ after the name of its first discovered site.
• An alternative term for the culture is Saraswati-Sindhu Civilization, based on the fact that most of the Indus Valley sites have been found at the Halkra-Ghaggar River.
• R.B. Dayaram Sahni first discovered Harappa (on Ravi) in 1921 and R.D. Banerjee discovered Mohenjodaro or ‘Mound of the Dead’ (on Indus) in 1922. Sir John Marshal had played a crucial role in both these.
• Harappan Civilization forms part of the proto history of India and belongs to the Bronze Age.
• Mediterranean, Proto-Australoid, Mongoloids and Alpines formed the bulk of the population, though the first two were more numerous.
• According to radio-carbon dating, it spread from the year 2500 – 1750 BC. Copper, bronze, silver, gold were known but not iron.
• Both places are now in Pakistan.
• The findings in these two cities brought to light a civilization which was first called the ‘The Indus Valley Civilization’.
• But this civilization was later named as the ‘Indus Civilization’ due to the discovery of more and more sites far away from the Indus valley.
• Also, it has come to be called the ‘Harappan Civilization’ after the name of its first discovered site.
• An alternative term for the culture is Saraswati-Sindhu Civilization, based on the fact that most of the Indus Valley sites have been found at the Halkra-Ghaggar River.
• R.B. Dayaram Sahni first discovered Harappa (on Ravi) in 1921 and R.D. Banerjee discovered Mohenjodaro or ‘Mound of the Dead’ (on Indus) in 1922. Sir John Marshal had played a crucial role in both these.
• Harappan Civilization forms part of the proto history of India and belongs to the Bronze Age.
• Mediterranean, Proto-Australoid, Mongoloids and Alpines formed the bulk of the population, though the first two were more numerous.
• According to radio-carbon dating, it spread from the year 2500 – 1750 BC. Copper, bronze, silver, gold were known but not iron.
ORIGIN AND EVOLUTION
• The archaeological findings excavated near the Indus Valley revealed the gradual development and four important stages or phases of evolution and they are named as pre-Harappan, early-Harappan, mature-Harappan and late Harappan.
• The pre-Harappan stage is located in eastern Baluchistan. The excavations at Mehrgarh 150 miles to the northwest of Mohenjodaro reveal the existence of pre-Harappan culture. In this stage, the nomadic people began to lead a settled agricultural life.
• In the early-Harappan stage, the people lived in large villages in the plains. There was a gradual growth of towns in the Indus valley. Also, the transition from rural to urban life took place during this period. The sites of Amri and Kot Diji remain the evidence for early-Harappan stage.
• In the mature-Harappan stage, great cities emerged. The excavations at Kalibangan with its elaborate town planning and urban features prove this phase of evolution.
• In the late-Harappan stage, the decline of the Indus culture started. The excavations at Lothal revealed this stage of evolution. Lothal with its port was founded much later. It was surrounded by a massive brick wall for flood protection. Lothal remained an emporium of trade between the Harappan civilization and the remaining part of India as well as Mesopotamia.
• The archaeological findings excavated near the Indus Valley revealed the gradual development and four important stages or phases of evolution and they are named as pre-Harappan, early-Harappan, mature-Harappan and late Harappan.
• The pre-Harappan stage is located in eastern Baluchistan. The excavations at Mehrgarh 150 miles to the northwest of Mohenjodaro reveal the existence of pre-Harappan culture. In this stage, the nomadic people began to lead a settled agricultural life.
• In the early-Harappan stage, the people lived in large villages in the plains. There was a gradual growth of towns in the Indus valley. Also, the transition from rural to urban life took place during this period. The sites of Amri and Kot Diji remain the evidence for early-Harappan stage.
• In the mature-Harappan stage, great cities emerged. The excavations at Kalibangan with its elaborate town planning and urban features prove this phase of evolution.
• In the late-Harappan stage, the decline of the Indus culture started. The excavations at Lothal revealed this stage of evolution. Lothal with its port was founded much later. It was surrounded by a massive brick wall for flood protection. Lothal remained an emporium of trade between the Harappan civilization and the remaining part of India as well as Mesopotamia.
GEOGRAPHICAL EXTENT
• Indus Valley Civilisation was the biggest of the contemporary ancient civilizations of the Nile or Tigris-Euphratus valleys in the west or the Yellow River Valley in the east.
• It formed a triangle and accounted for about 12,99,600 km with Sutkagendor in Makran coast, Alamgirpur in Meerut district of U.P., Manda in Jammu and Daimabad forming its western, eastern and northern and southernmost points, respectively.
• From east to west it is a distance of 1,550 km and from north to south it extends over 1,100 km.
• Major sites in Pakistan of Harappan civilization are Harappa (on Ravi in W Punjab), Mohenjodaro (on Indus), Chanhu-Daro (on Sindh), etc. In India, major sites are Lothal, Rangpur and Surkotda (Gujarat), Kalibangan (Rajasthan), Banwali (Hissar), and Alamgirpur (Western UP). Largest and the latest site discovered in India is Dholavira in Gujarat.

INDUS VALLEY CIVILIZATION SITES
So far nearly 1000 sites of nearly, mature and late phases of the Indus Civilization are known in the sub-continent. But the number of the sites belonging to the mature phase is limited, and of them only half a dozen like Mohenjo-daro, Harappa, Kalibangan, Lothal, Chanhu-daro and Banwali can be regarded as cities.
Of these, Mohenjo-daro and Harappa situated at a distance of 483 km and linked together by the river Indus are most important, both on account of their size and the diversity of the finds, which excavations have revealed.
• Indus Valley Civilisation was the biggest of the contemporary ancient civilizations of the Nile or Tigris-Euphratus valleys in the west or the Yellow River Valley in the east.
• It formed a triangle and accounted for about 12,99,600 km with Sutkagendor in Makran coast, Alamgirpur in Meerut district of U.P., Manda in Jammu and Daimabad forming its western, eastern and northern and southernmost points, respectively.
• From east to west it is a distance of 1,550 km and from north to south it extends over 1,100 km.
• Major sites in Pakistan of Harappan civilization are Harappa (on Ravi in W Punjab), Mohenjodaro (on Indus), Chanhu-Daro (on Sindh), etc. In India, major sites are Lothal, Rangpur and Surkotda (Gujarat), Kalibangan (Rajasthan), Banwali (Hissar), and Alamgirpur (Western UP). Largest and the latest site discovered in India is Dholavira in Gujarat.

INDUS VALLEY CIVILIZATION SITES
So far nearly 1000 sites of nearly, mature and late phases of the Indus Civilization are known in the sub-continent. But the number of the sites belonging to the mature phase is limited, and of them only half a dozen like Mohenjo-daro, Harappa, Kalibangan, Lothal, Chanhu-daro and Banwali can be regarded as cities.
Of these, Mohenjo-daro and Harappa situated at a distance of 483 km and linked together by the river Indus are most important, both on account of their size and the diversity of the finds, which excavations have revealed.
Mohenjo-daro
• Literally, the ‘mound of the dead’ is situated in Larkana district of Sind on the right bank of the River Indus. Mohenjo-Daro was first excavated by R.D. Banerjee in 1922.
• This city is also an extreme example of conservatism, as despite having been fl ooded almost nine times,they never tried to shift to a safer place. Rather, they came back to the original site whenever the water table receded. Nor did they ever try to build strong embankments to protect themselves from fl oods.
• The major findings here include a citadel, a college, a multi-pillared Assembly Hall, a public bath (the Great Bath) and a large granary (inside the citadel) consisting of a podium of square blocks and burnt with a wooden superstructure.
• The Great Bath was excavated by Sir John Marshal and regarded as the most important public place measuring 11.88 metres, 7.01 metres and 2.43 metres deep approachable by two staircases from north and south; around it was a pillared verandah with dressing rooms. It is an example of beautiful brickwork, bitumen coated with gypsum in mortar made it water proof. Perhaps it was used for ritual bathing.
• A piece of woven cotton; bronze dancing girl; seals of three-headed Pashupati Mahadeo; steatite-statuette of a bearded man supposed to be a priest-king; terracotta figurines of a horse from a superficial level; a seal and two potshed depicting ships; bronze buffalo and ram, etc. are the major findings here.
• Three cylindrical seals of Mesopotamina type have also been found here.
• Literally, the ‘mound of the dead’ is situated in Larkana district of Sind on the right bank of the River Indus. Mohenjo-Daro was first excavated by R.D. Banerjee in 1922.
• This city is also an extreme example of conservatism, as despite having been fl ooded almost nine times,they never tried to shift to a safer place. Rather, they came back to the original site whenever the water table receded. Nor did they ever try to build strong embankments to protect themselves from fl oods.
• The major findings here include a citadel, a college, a multi-pillared Assembly Hall, a public bath (the Great Bath) and a large granary (inside the citadel) consisting of a podium of square blocks and burnt with a wooden superstructure.
• The Great Bath was excavated by Sir John Marshal and regarded as the most important public place measuring 11.88 metres, 7.01 metres and 2.43 metres deep approachable by two staircases from north and south; around it was a pillared verandah with dressing rooms. It is an example of beautiful brickwork, bitumen coated with gypsum in mortar made it water proof. Perhaps it was used for ritual bathing.
• A piece of woven cotton; bronze dancing girl; seals of three-headed Pashupati Mahadeo; steatite-statuette of a bearded man supposed to be a priest-king; terracotta figurines of a horse from a superficial level; a seal and two potshed depicting ships; bronze buffalo and ram, etc. are the major findings here.
• Three cylindrical seals of Mesopotamina type have also been found here.
Harappa
• It is situated in the Montgomery district of Punjab, now in Pakistan on the left bank of the River Ravi.
• It is perhaps the largest Indus site in magnitude and dimension. The structures of Harappa cover 5 km in circuit and in the way is one of the largest of its type in the Bronze Age.
• The vast mounds at Harappa were first reported by Charles Masson in 1826, and preliminary excavation was done by Daya Ram Sahni in 1921.
• Major findings include – a granary (outside the citadel) consisting of twelve oblong blocks in an area 800 sq. metres; between the granary and the citadel have also been found a series of circular platforms probably for the pounding of grain, because wheat and barley have been found in the crevices.
• Little bullock carts and ‘Ekkas’ besides copper or bronze models of carts with seated drivers have also been found.
• It is the only site, which yields the evidence of coffin burial probably of a foreigner from the west. Rigveda (Mandal VI) mentions it as ‘Harupiya’ – a battle site ruins.
• It is situated in the Montgomery district of Punjab, now in Pakistan on the left bank of the River Ravi.
• It is perhaps the largest Indus site in magnitude and dimension. The structures of Harappa cover 5 km in circuit and in the way is one of the largest of its type in the Bronze Age.
• The vast mounds at Harappa were first reported by Charles Masson in 1826, and preliminary excavation was done by Daya Ram Sahni in 1921.
• Major findings include – a granary (outside the citadel) consisting of twelve oblong blocks in an area 800 sq. metres; between the granary and the citadel have also been found a series of circular platforms probably for the pounding of grain, because wheat and barley have been found in the crevices.
• Little bullock carts and ‘Ekkas’ besides copper or bronze models of carts with seated drivers have also been found.
• It is the only site, which yields the evidence of coffin burial probably of a foreigner from the west. Rigveda (Mandal VI) mentions it as ‘Harupiya’ – a battle site ruins.
Kalibangan (Sothi culture)
• It is situated in Ganga Nagar district of northern Rajasthan on the banks of the now dry course of the Ghaggar River and was first excavated by A. Ghoshin 1953.
• Here, the massive mud-brick wall around citadel and lower town was supported by corner tower and ‘bastions’.
• Evidence of furrows land (pre-Harappan) and wooden furrow comes from this site only.
• Evidence of fire-altar in houses suggests the practice of fire-cult.
• Copper was known, as is attested by copper bead as well as a cell and few other objectives.
• The existence of wheel conveyance is proved by a cartwheel having a single hub.
• The pottery has six fabrics, all wheel made, as at Kot-Diji, but unlike Amri, where in the lowest levels, the majority was hand-made.
• The predominant pottery is red or pink with black, or bichrome black white painting.
• Animal sacrifice is suggested by a big public fire-pit altar made of burnt bricks on a platform situated in the outer city containing bones of cattle. At this site evidence of restricted use of bunt bricks confined largely to bathrooms, wells and latrines.
• There is no clear-cut evidence of drainage system here.
• Bones of a camel.
• It is situated in Ganga Nagar district of northern Rajasthan on the banks of the now dry course of the Ghaggar River and was first excavated by A. Ghoshin 1953.
• Here, the massive mud-brick wall around citadel and lower town was supported by corner tower and ‘bastions’.
• Evidence of furrows land (pre-Harappan) and wooden furrow comes from this site only.
• Evidence of fire-altar in houses suggests the practice of fire-cult.
• Copper was known, as is attested by copper bead as well as a cell and few other objectives.
• The existence of wheel conveyance is proved by a cartwheel having a single hub.
• The pottery has six fabrics, all wheel made, as at Kot-Diji, but unlike Amri, where in the lowest levels, the majority was hand-made.
• The predominant pottery is red or pink with black, or bichrome black white painting.
• Animal sacrifice is suggested by a big public fire-pit altar made of burnt bricks on a platform situated in the outer city containing bones of cattle. At this site evidence of restricted use of bunt bricks confined largely to bathrooms, wells and latrines.
• There is no clear-cut evidence of drainage system here.
• Bones of a camel.
Lothal
• It is situated in Gujarat on Bhogavar River near Gulf of Cambay.
• It was excavated by Prof. S.R. Rao in 1957. It is a small but interesting site.
• It differs from the other sites so far as the houses open on to the main street and there is no citadel complex.
• An interesting finding here is an artificial brick dockyard (219×37 meters) connected through the Bhogavar River with the Gulf of Cambay.
• It is the only place along with Rangpur where rice husk has been found. Terracotta figurines of a horse are also found here.
• Terracotta model of a ship with a stick-impressed socket for the mast and eyeholes for fixing rigging, which is found here, may suggest sea trade.
• Fire attars have also been found.
• It is the only Indus site, which bears the evidence of joint burial of male and female suggesting the practice of ‘Sati’.
• A ‘Persian Gulf’ type of seal has been found here.
• The site is also known for bead-makers factory.
• It is situated in Gujarat on Bhogavar River near Gulf of Cambay.
• It was excavated by Prof. S.R. Rao in 1957. It is a small but interesting site.
• It differs from the other sites so far as the houses open on to the main street and there is no citadel complex.
• An interesting finding here is an artificial brick dockyard (219×37 meters) connected through the Bhogavar River with the Gulf of Cambay.
• It is the only place along with Rangpur where rice husk has been found. Terracotta figurines of a horse are also found here.
• Terracotta model of a ship with a stick-impressed socket for the mast and eyeholes for fixing rigging, which is found here, may suggest sea trade.
• Fire attars have also been found.
• It is the only Indus site, which bears the evidence of joint burial of male and female suggesting the practice of ‘Sati’.
• A ‘Persian Gulf’ type of seal has been found here.
• The site is also known for bead-makers factory.
Chaunhudaro
• It is situated in Sind on the lefts plains of the Indus about 130 km south of Mohenjo-daro.
• It has no citadel.
• The site is most famous for bead-makers factory.
• The site was a major centre for craft production – seal, shell bead and bangle manufacturing shops.
• Other findings include a small pot, probably an inkpot; evidence of mustard; foot prints of a dog chasing those of a cat across one wet surface of some brickwork; copper or bronze models of carts with seated drivers etc.
• It is situated in Sind on the lefts plains of the Indus about 130 km south of Mohenjo-daro.
• It has no citadel.
• The site is most famous for bead-makers factory.
• The site was a major centre for craft production – seal, shell bead and bangle manufacturing shops.
• Other findings include a small pot, probably an inkpot; evidence of mustard; foot prints of a dog chasing those of a cat across one wet surface of some brickwork; copper or bronze models of carts with seated drivers etc.
Kot-Diji
• It is situated at a distance of 100 miles north-east of Amri on the left bank of the Indus and was excavated in and after 1955 by the Pakistan Archaeological department.
• There are indications at various points that the early settlement was subject to floods and that stones were piled up as a protection against their action.
• The material culture included a chart-blade industry with some serrated blades, and other blades reportedly bearing ‘sickle glass’.
• It is not clear whether there were any objects of copper but a fragment of a bronze bangle is reported.
• The pottery was of a distinctive character, which was decorated to have developed from bands of brownish paint.
• An interesting motif appears to have developed from bands of loops and wavy lines into the well-known fish-scale pattern, which later appears on Harappan pottery.
• With the exception of writing and long stone blades, the Kot-Dijians had everything that Harappans were known for.
• At Kot-Diji the foundations of the fortification wall and houses are of stone.
• There is plenty of evidence to show that Kot-Diji was destroyed of fire.
• It is situated at a distance of 100 miles north-east of Amri on the left bank of the Indus and was excavated in and after 1955 by the Pakistan Archaeological department.
• There are indications at various points that the early settlement was subject to floods and that stones were piled up as a protection against their action.
• The material culture included a chart-blade industry with some serrated blades, and other blades reportedly bearing ‘sickle glass’.
• It is not clear whether there were any objects of copper but a fragment of a bronze bangle is reported.
• The pottery was of a distinctive character, which was decorated to have developed from bands of brownish paint.
• An interesting motif appears to have developed from bands of loops and wavy lines into the well-known fish-scale pattern, which later appears on Harappan pottery.
• With the exception of writing and long stone blades, the Kot-Dijians had everything that Harappans were known for.
• At Kot-Diji the foundations of the fortification wall and houses are of stone.
• There is plenty of evidence to show that Kot-Diji was destroyed of fire.
Amri
• It is situated in Sind west of the River Indus and was excavated under the direction of N.G. Majumdar in 1929 and later by a French team directed by J.M. Casal.
• Here, fragments of copper and bronze, a chart blade industry, wheel thrown pottery showing a wide variety of painted motifs, mainly geometric, in both plain and polychrome styles have been found.
• From this site, comes a beautiful painted humped Indian bull.
• It is situated in Sind west of the River Indus and was excavated under the direction of N.G. Majumdar in 1929 and later by a French team directed by J.M. Casal.
• Here, fragments of copper and bronze, a chart blade industry, wheel thrown pottery showing a wide variety of painted motifs, mainly geometric, in both plain and polychrome styles have been found.
• From this site, comes a beautiful painted humped Indian bull.
Surkotada
• It is a coastal site and is situated at the head of Rann of Kutch in Gujarat.
• It was first excavated by J. Joshi in 1964.
• Here, both citadel and lower town is fortified – the two being connected by an intercommunicating gate.
• The most important finding here are the bones of horse (2000 BC).
• It is a coastal site and is situated at the head of Rann of Kutch in Gujarat.
• It was first excavated by J. Joshi in 1964.
• Here, both citadel and lower town is fortified – the two being connected by an intercommunicating gate.
• The most important finding here are the bones of horse (2000 BC).
Sulkagendor
• It is on the Makran coast where Sir Aurel Stein dug some trial trenches.
• There is existence of a great fortification around the Harappan outpost here.
• The citadel here was fortified in rubble stone instead of bricks.
• Perhaps the site was a trading port.
• It is on the Makran coast where Sir Aurel Stein dug some trial trenches.
• There is existence of a great fortification around the Harappan outpost here.
• The citadel here was fortified in rubble stone instead of bricks.
• Perhaps the site was a trading port.
Banwali
• It is situated in Hissar district of Haryana on the bank of the now dry course of river Sarasvati.
• It was first excavated in 1974 by R.S. Bisht.
• A good quantity of barley has been found here.
• The sites like Kalibangan also show pre-Harappan and Harappan phases.
• It is situated in Hissar district of Haryana on the bank of the now dry course of river Sarasvati.
• It was first excavated in 1974 by R.S. Bisht.
• A good quantity of barley has been found here.
• The sites like Kalibangan also show pre-Harappan and Harappan phases.
Ropar
• It is situated in the district of the same name in Punjab on the bank of river Sutlej and was first excavated by Y.D. Sharma in 1953.
• Both Harappan and post-Harappan phase have been noticed here.
• It is situated in the district of the same name in Punjab on the bank of river Sutlej and was first excavated by Y.D. Sharma in 1953.
• Both Harappan and post-Harappan phase have been noticed here.
Rangpur
• It is situated in Jhalwar district of Gujarat near Ahmedabad and was excavated by M.S. Vats in 1931.
• All three phases of Harappan culture i.e. pre-Harappan, Harappan and post-Harappan have been found here.
• The most important finding here are rice husks.
• No seal or image of Mother Goddess has been found here.
• It is situated in Jhalwar district of Gujarat near Ahmedabad and was excavated by M.S. Vats in 1931.
• All three phases of Harappan culture i.e. pre-Harappan, Harappan and post-Harappan have been found here.
• The most important finding here are rice husks.
• No seal or image of Mother Goddess has been found here.
Alamgirpur
• It is situated in Meerut district of U.P. and represents the last phase i.e. of post-Harappan culture.
• It is situated in Meerut district of U.P. and represents the last phase i.e. of post-Harappan culture.
Ali Murad
• It is situated in Sind and has yielded a massive stone fort.
• It is situated in Sind and has yielded a massive stone fort.
Dholavira
• It is situated in Gujarat and seems to be a big site but is not much excavated.
• It is situated in Gujarat and seems to be a big site but is not much excavated.
DECLINE OF INDUS VALLEY CIVILIZATION
Traces of general decline in civic standard are noticed towards the last phase of Indus Civilization. Town planning was abandoned and public buildings fell in ruin. Water supply system fell in disrepair. Kiln entered city limits. Dilapidated bricks were roused. Script degenerated. Weights and measures and seals disappeared. External and internal trade declined. Some exotic tools and pottery found in the upper levels indicate foreign intrusion in the north. Several causes have been given for the decline.
• There is no unanimous view pertaining to the cause for the decline of the Harappan culture. Various theories have been postulated.
• Natural calamities like recurring floods, drying up of rivers, decreasing fertility of the soil due to excessive exploitation and occasional earthquakes might have caused the decline of the Harappan cities.
• According to some scholars the final blow was delivered by the invasion of Aryans.
• The destruction of forts is mentioned in the Rig Veda. Also, the discovery of human skeletons huddled together at Mohenjodaro indicates that the city was invaded by foreigners.
• The Aryans had superior weapons as well as swift horses which might have enabled them to become masters of this region.
Traces of general decline in civic standard are noticed towards the last phase of Indus Civilization. Town planning was abandoned and public buildings fell in ruin. Water supply system fell in disrepair. Kiln entered city limits. Dilapidated bricks were roused. Script degenerated. Weights and measures and seals disappeared. External and internal trade declined. Some exotic tools and pottery found in the upper levels indicate foreign intrusion in the north. Several causes have been given for the decline.
• There is no unanimous view pertaining to the cause for the decline of the Harappan culture. Various theories have been postulated.
• Natural calamities like recurring floods, drying up of rivers, decreasing fertility of the soil due to excessive exploitation and occasional earthquakes might have caused the decline of the Harappan cities.
• According to some scholars the final blow was delivered by the invasion of Aryans.
• The destruction of forts is mentioned in the Rig Veda. Also, the discovery of human skeletons huddled together at Mohenjodaro indicates that the city was invaded by foreigners.
• The Aryans had superior weapons as well as swift horses which might have enabled them to become masters of this region.
Weeds
Weeds
Weeds are wild, unwanted plants that compete with normal healthy plants for water, light, soil nutrients and space. Weeds are competitive, persistent, pernicious, and interfere negatively with human activity. There are approximately 250,000 species of plants worldwide; of those, about 3% or 8000.species behaves as weeds.
Negative impacts of weeds are:
• They reduce crop quality by contaminating the commodity.
• They interfere with harvest and reduce the efficiency of farm equipment.
• Weeds reduce the carrying capacity of grazing lands and pastures.
• They serve as hosts for crop diseases or provide shelter for insects during winter. They limit the choice of crop rotation sequences and, cultural practices.
• Weeds produce chemical substances which are toxic to crop plants (allelopathy), animals or humans.
• Weedicides prove to be costly and harmful to the environment. Some weeds are parasites, either partially or totally, on crop plants.
• Weeds impair quality and quantity of plant and animal products. Example: thorny weeds.
• Seeds of some weeds are similar to crop seeds and it is very difficult to separate them, once mixed. Example: Argemone mexicana (Prickly poppy) has seeds resembling to mustard seeds. This adulteration of mustard by poppy has lead to a disease called Dropsy.
• They reduce crop quality by contaminating the commodity.
• They interfere with harvest and reduce the efficiency of farm equipment.
• Weeds reduce the carrying capacity of grazing lands and pastures.
• They serve as hosts for crop diseases or provide shelter for insects during winter. They limit the choice of crop rotation sequences and, cultural practices.
• Weeds produce chemical substances which are toxic to crop plants (allelopathy), animals or humans.
• Weedicides prove to be costly and harmful to the environment. Some weeds are parasites, either partially or totally, on crop plants.
• Weeds impair quality and quantity of plant and animal products. Example: thorny weeds.
• Seeds of some weeds are similar to crop seeds and it is very difficult to separate them, once mixed. Example: Argemone mexicana (Prickly poppy) has seeds resembling to mustard seeds. This adulteration of mustard by poppy has lead to a disease called Dropsy.
Methods of Weed Control
• Chemical control involves the use of herbicides. Herbicides control weed plants either by speeding up, stopping or changing the plant’s normal growth patterns; by desiccating (drying out) the leaves or stems; or by defoliating the plant (making it drop its leaves).
• Mechanical control is the use of powered tools and machinery to manage weeds. It is suitable for larger infestations because it reduces the weed bulk with less manual effort. Care should be taken to minimize soil disturbance.
• Biological control involves the use of insects or pathogens (diseases) that affect the health of the weed. Usually, these bio-control agents are from the same country of origin as the weed species.
• Manual control is the use of the hands or handheld tools to deal with weeds. An advantage of manual control is that it minimizes soil disturbance, and decreases the likelihood of erosion and weed seed germination.
• Chemical control involves the use of herbicides. Herbicides control weed plants either by speeding up, stopping or changing the plant’s normal growth patterns; by desiccating (drying out) the leaves or stems; or by defoliating the plant (making it drop its leaves).
• Mechanical control is the use of powered tools and machinery to manage weeds. It is suitable for larger infestations because it reduces the weed bulk with less manual effort. Care should be taken to minimize soil disturbance.
• Biological control involves the use of insects or pathogens (diseases) that affect the health of the weed. Usually, these bio-control agents are from the same country of origin as the weed species.
• Manual control is the use of the hands or handheld tools to deal with weeds. An advantage of manual control is that it minimizes soil disturbance, and decreases the likelihood of erosion and weed seed germination.
Environmental Crime In India
Environmental Crime In India
• Environmental crimes i.e. the crimes manipulating environment inter-alia involves air pollution, water pollution, and the illegal transportation, storage, and disposal of hazardous waste, which causes most serious threat to public health and natural resources. One of such serious crimes is ‘poaching’ i.e. illegal wildlife trade.
• While data is easily available on pollution levels and emissions, statistics on crimes against the environment are harder to come by. So, in 2014, the National Crime Records Bureau (NCRB) compiled data on environment-related offences.
• Offences against the environment are registered under the following five laws
a) Water (Prevention & Control of Pollution) Act, 1974 (as amended in 1988)
b) Air (Prevention & Control of Pollution) Act, 1981
c) Environmental (Protection) Act, 1986
d) Wildlife Protection Act, 1972
e) Forest Act, 1927
b) Air (Prevention & Control of Pollution) Act, 1981
c) Environmental (Protection) Act, 1986
d) Wildlife Protection Act, 1972
e) Forest Act, 1927
• Wildlife and forest crime has a serious role in threat finance to organized crime, and non-state armed groups including terrorist groups.
• International enforcement collaboration, such as the International Consortium on Combating Wildlife Crime (ICCWC), which includes CITES, UNODC, INTERPOL, the World Bank and WCO, together with increased collaboration amongst agencies, such as with UNEP, and with countries, has created a more effective structure to provide support to countries in the fields of policing, customs, prosecution and the judiciary. These initiatives have revealed important and significant early results.
• However, the scale and coordination of the efforts must be substantially increased and a widened effort implemented. They must be combined with efforts on good governance, management and consumer awareness to ensure a long-term demand reduction.
• In India Wildlife Crime Control Bureau has been formed in 2007, by amending the Wildlife (Protection) Act, 1972, a special Act to protect the wildlife in the country. The bureau would complement the efforts of the state governments, primary enforcers of the Wildlife (Protection) Act, 1972 and other enforcement agencies of the country.
• It is mandated to collect and collate intelligence related to organized wildlife crime activities and to disseminate the same to State and other enforcement agencies for immediate action so as to apprehend the criminals; to establish a centralized wildlife crime data bank; co-ordinate actions by various agencies in connection with the enforcement of the provisions of the Act; assist foreign authorities and international organization concerned to facilitate co-ordination and universal action for wildlife crime control; capacity building of the wildlife crime enforcement agencies for scientific and professional investigation into wildlife crimes and assist State Governments to ensure success in prosecutions related to wildlife crimes; and advise the Government of India on issues relating to wildlife crimes having national and international ramifications, relevant policy and laws. It also assists and advises the Customs authorities in inspection of the consignments of flora & fauna as per the provisions of Wild Life Protection Act, CITES and EXIM Policy governing such an item.
Use of Microbes
Use of Microbes
Microorganisms are very tiny living things. Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and some algae. Microorganisms are used for various purposes.
1. Microbes in sewage treatment
• The municipal waste-water known as sewage contains large amounts of organic matter and microbes. These microorganisms are used for treatment of waste water.
• In the primary stage of waste water treatment physical removal of particles from the sewage through filtration and sedimentation occurs.
• In the secondary stage of waste water treatment the primary effluent is passed into large aeration tanks, this allows vigorous growth of aerobic microbes into flocs.
These microbes consume the major part of the organic matter in the effluent. This significantly reduces the BOD (biochemical oxygen demand) of the effluent. BOD is a measure of the organic matter present in the water. The greater the BOD of waste water, more is its polluting potential.
• Further in the anaerobic sludge digesters bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide. These gases form biogas.
• The municipal waste-water known as sewage contains large amounts of organic matter and microbes. These microorganisms are used for treatment of waste water.
• In the primary stage of waste water treatment physical removal of particles from the sewage through filtration and sedimentation occurs.
• In the secondary stage of waste water treatment the primary effluent is passed into large aeration tanks, this allows vigorous growth of aerobic microbes into flocs.
These microbes consume the major part of the organic matter in the effluent. This significantly reduces the BOD (biochemical oxygen demand) of the effluent. BOD is a measure of the organic matter present in the water. The greater the BOD of waste water, more is its polluting potential.
• Further in the anaerobic sludge digesters bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide. These gases form biogas.
2. Microbes in production of biogas
• Certain bacteria, which grow anaerobically on cellulosic material, produce large amount of methane along with CO2 and H2
• These bacteria are collectively called methanogens, and one such common bacterium is Methanobacterium. These bacteria are commonly found in the anaerobic sludge during sewage treatment and produces biogas.
• Certain bacteria, which grow anaerobically on cellulosic material, produce large amount of methane along with CO2 and H2
• These bacteria are collectively called methanogens, and one such common bacterium is Methanobacterium. These bacteria are commonly found in the anaerobic sludge during sewage treatment and produces biogas.
*Methogens are also present in the rumen (a part of stomach) of cattle. A lot of cellulosic material present in the food of cattle is also present in the rumen. In rumen, these bacteria help in the breakdown of cellulose and play an important role in the nutrition of cattle.*
• The technology of biogas production was developed in India mainly due to the efforts of Indian Agricultural Research Institute (IARI) and Khadi and Village Industries Commission (KVIC).
3. Microbes as biocontrol agents
• Biocontrol refers to the use of biological methods for controlling plant diseases and pests.
• In agriculture for controlling pests natural predation methods should be used rather than use of chemicals.
• An important part of the biological farming approach is to become familiar with the various life forms that inhabit the field, predators as well as pests, and also their life cycles, patterns of feeding and the habitats that they prefer. This will help develop appropriate means of biocontrol.
• Some examples:
• Biocontrol refers to the use of biological methods for controlling plant diseases and pests.
• In agriculture for controlling pests natural predation methods should be used rather than use of chemicals.
• An important part of the biological farming approach is to become familiar with the various life forms that inhabit the field, predators as well as pests, and also their life cycles, patterns of feeding and the habitats that they prefer. This will help develop appropriate means of biocontrol.
• Some examples:
– Lady bird – to control aphids
– Dragon fly – to control mosquitoes
– Bacillus thuringiensis (Bt Cotton) – to control wide range insects
– Trichoderma (fungi) – protects root system and control plant pathogens.
– Baculoviruses (Nucleopolyhedrovirus) – to attack insects and other arthropods.
– Dragon fly – to control mosquitoes
– Bacillus thuringiensis (Bt Cotton) – to control wide range insects
– Trichoderma (fungi) – protects root system and control plant pathogens.
– Baculoviruses (Nucleopolyhedrovirus) – to attack insects and other arthropods.
• This is especially desirable when beneficial insects are being conserved to aid in an overall integrated pest management (IPM) programme, or when an ecologically sensitive area is being treated.
4. Microbes as biofertilisers
• Biofertilisers are organisms that enrich the nutrient quality of the soil. The main sources of biofertilisers are bacteria, fungi and cyanobacteria.
Bacteria: Symbiosis – Rhizobium with root nodules of leguminous plants; Free living (in the soil) – Azotobacter and Azospirillum.
Fungi: Symbiosis – Mycorrhiza with root system of genus Glomus and absorb phosphorus and water from the soil for the plant growth.
Cyanobacteria: Symbiosis – Anabaena in Azolla; Free living – Nostoc, Oscillatoria and Blue green algae.
• Biofertilisers are organisms that enrich the nutrient quality of the soil. The main sources of biofertilisers are bacteria, fungi and cyanobacteria.
Bacteria: Symbiosis – Rhizobium with root nodules of leguminous plants; Free living (in the soil) – Azotobacter and Azospirillum.
Fungi: Symbiosis – Mycorrhiza with root system of genus Glomus and absorb phosphorus and water from the soil for the plant growth.
Cyanobacteria: Symbiosis – Anabaena in Azolla; Free living – Nostoc, Oscillatoria and Blue green algae.
5. Production of alcohol and wine
Microorganism such as Yeast is used for the large scale production of alcohol, wine and acetic acid (vinegar).
Microorganism such as Yeast is used for the large scale production of alcohol, wine and acetic acid (vinegar).
6. Production of antibiotics
• Antibiotics are chemical substances, which are produced by some microbes and can kill or retard the growth of other (disease-causing) microbes such as Penicillin.
• Antibiotics are even mixed with the feed of livestock and poultry to check microbial infection in animals. They are also used to control many plant diseases.
• Antibiotics are chemical substances, which are produced by some microbes and can kill or retard the growth of other (disease-causing) microbes such as Penicillin.
• Antibiotics are even mixed with the feed of livestock and poultry to check microbial infection in animals. They are also used to control many plant diseases.
7. Production of Amino acids
• It is used for production of amino acids on a commercial scale. They are used in food industry as flavor and taste enhances (Eg: Glutamic acid), as artificial sweeteners in soft drink industry (Eg: Glycine, Aspartame), in pharmaceutical industry (Eg: Ornithine- treatment of liver disease, Histidine and Glutamine- therapy for ulcers).
• It is used for production of amino acids on a commercial scale. They are used in food industry as flavor and taste enhances (Eg: Glutamic acid), as artificial sweeteners in soft drink industry (Eg: Glycine, Aspartame), in pharmaceutical industry (Eg: Ornithine- treatment of liver disease, Histidine and Glutamine- therapy for ulcers).
8. Production of Chemicals, Enzymes and other Bioactive Molecules
• Microbes are being used for commercial and industrial production of certain chemicals like organic acids, alcohols, enzymes and other bioactive molecules.
• Microbes are being used for commercial and industrial production of certain chemicals like organic acids, alcohols, enzymes and other bioactive molecules.
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