Habitat Destruction

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HABITAT
DESTRUCTION
CAUSES AND CONSEQUENCES
HABITAT DESTRUCTION
Every living thing requires somewhere to live, find food and
reproduce.
This is known as its habitat. In order for a species to be viable its
habitat must have sufficient territory, necessary food and water
and a range of necessary physical features. These features can
include tree cover, rocky hills or deep pools, as well as the
organisms and ecosystems that are needed to complete the life
cycle.
Habitat destruction is the process in which natural habitat is
rendered functionally unable to support the species present. In
this process, the organisms that previously used the site are
displaced or destroyed, reducing biodiversity.
Whenever we humans take over natural areas for our own use,
we are encroaching on the habitat of another creature and
progressively we are doing this at an alarming rate.
HABITAT DESTRUCTION
Causes of Habitat Destruction
• Deforestation
• Desertification
• Urbanization
• Introduction of invasive Species of Plants or Animals
• Pollution
• Natural causes such as Wildfires, Volcanism and Climate
Change
FOREST HABITATS
Human activity is responsible for the loss of around half of the
forests that once covered the Earth. Although these can recover
and can even be sustainably harvested, their rate of loss is about
ten times higher than the rate of regrowth.
Because of Rainforest habitat loss it is estimated that at least 120
out of the 620 living primate species (apes, monkeys, lemurs and
others) will be extinct within the next 10 to 20 years.
Example : Gorilla
It is estimated that about 80 percent of the gorilla population
is extinct. Gorillas face threat in wherever place they live.
Destruction of habitat, hunting by humans and diseases
caused by Ebola virus are the reasons for extinction.
FOREST HABITATS
Major Causes of Deforestation in India
•
Agriculture. With raise in the demands for agricultural products, forests are
being destroyed to render space for cultivating crops and building farms, where
especially cultivators are encouraged by the government to work on the areas.
Moreover, the planters use fire in the development, which leads to the emission
of large amounts of carbon dioxide and carbon monoxide in an environment
that creates a pessimistic blow on the biology.
•
Wood Harvesting. Trees are cut down for attaining lumber or timber that is a
wood used for constructing houses and making furniture. It is the most
significant cause of deforestation.
•
Grazing Land. Forests are also cleared for cattle grazing, which have made
them one of the most heavily exploited.
•
Mining. Excavating a diamond or coal means clearing of all woodland cover
with the help of trucks and many other types of equipment
•
Palm Oil. Palm oil has been in great demands in the market and its
intensifying costs making it more priceless. Therefore, farmers are exploiting
acres of land of forests to reap it.
FOREST HABITATS
Example : Bengal Tiger
The Bengal tiger is an extremely endangered species living in the
mangrove forests of the Sundarban regions of India, Bangladesh,
China, Siberia and Indonesia.
At present there are less than 2,500 of this species left, while
there were more than 45,000 in 1900.
Poaching and destruction of habitat are the reasons for this
species getting endangered.
India's National Parks are being mismanaged, and there are not
enough guards to stop the poaching of tigers.
Example : Asiatic Lion
The Asiatic lion currently exists as a single subpopulation, and is
thus vulnerable to extinction from unpredictable events, such as
an Epidemic or Large Forest Fire.
The Gir forest was heavily degraded and used by livestock, which
competed with and restricted the population sizes of native
ungulates.
FOREST HABITATS
Consequences Of Deforestation
•
Loss of Species. Seventy percent of the world’s plants and animals live in
forests and are losing their habitats to deforestation. Loss of habitat can lead to
species extinction.
•
Carbon Emissions. Healthy forests help absorb greenhouse gasses and
carbon emissions that are caused by human civilization and contribute to global
climate change. Without trees, more carbon and greenhouse gasses enter the
atmosphere.
To make matters worse, trees actually become carbon sources when they are
cut, burned, or otherwise removed.
•
Water Cycle. Trees play an important part in the water cycle, grounding the
water in their roots and releasing it into the atmosphere. In the Amazon, more
than half the water in the ecosystem is held within the plants. Without the
plants, the climate may become dryer.
•
Soil Erosion. Without tree roots to anchor the soil and with increased
exposure to sun, the soil can dry out, leading to problems like increased
flooding and inability to farm.
FOREST HABITATS
Example : Red Sandalwood Tree
It is only found in south India in Kadapa, Chittoor, mostly
in the hilly region of Nepal, in Pakistan and in Sri Lanka.
This species is listed as Endangered by the IUCN,
because of overexploitation for its timber.
Example : Kulavetti Tree
In 1998 the International Union for Conservation of Nature (IUCN)
listed the tree species as in extreme danger of extinction when
less that 200 were reported from Kerala, the only place in the
world where the tree grows. The primary cause of this loss was
habitat destruction.
MARINE HABITATS
Most areas of the world's oceans are experiencing habitat loss.
But coastal areas, with their closeness to human population
centers, have suffered disproportionately and mainly from
manmade stresses.
Habitat loss here has far-reaching impacts on the entire ocean's
biodiversity.
These critical areas, which include estuaries, swamps, marshes,
and wetlands, serve as breeding grounds or nurseries for nearly
all marine species.
MARINE HABITATS
Sea Corals
They are an important part of the
ocean's ecosystem. Coral gives other
sea creatures protection and a place
to breed and spawn.
ocean acidification and bottom
trawling commercial fishing are its
major threats.
Hawksbill Turtle
Found in the tropical regions of all the world’s
oceans, gulfs and seas, this Hawksbill Turtle’s
population has been estimated to have declined
by 80% over the last century.
Known to be a subject of heavy trafficking in the
tourist trade in tropical regions for its meat and
shells, these are being killed mercilessly for quite
a period of time.
MARINE HABITATS
Causes Of Marine Habitat Loss
•
Hurricanes and typhoons, storm surges, tsunamis and the like can cause
massive, though usually temporary, disruptions in the life cycles of ocean plants
and animals.
Human activities, however, are significantly more impactful and persistent
•
Wetlands are dredged and filled in to accommodate urban, industrial, and
agricultural development
•
Cities, factories, and farms create waste, pollution, and chemical effluent and
runoff that can wreak havoc on reefs, sea grasses, birds, and fish
•
Inland dams decrease natural nutrient-rich runoff, cut off fish migration routes,
and curb freshwater flow, increasing the salinity of coastal waters
•
Destructive fishing techniques like bottom trawling, dynamiting, and poisoning
destroy habitats near shore as well as in the deep sea
•
Tourism brings millions of boaters, snorkelers, and scuba divers into direct
contact with fragile wetland and reef ecosystems.
•
Container ships and tankers can damage habitat with their hulls and anchors
•
Spills of crude oil and other substances kill thousands of birds and fish and
leave a toxic environment that can persist for years
MARINE HABITATS
The Pondicherry Shark
This Shark is heavily endangered due to
the large, expanding, and unregulated
artisanal and commercial fisheries.
It was found in the Indo-pacific region in
shallow coastal seas.
The Blue Whale
The largest living mammal on earth, the blue
whale could be found migrating from both poles
in the oceans around the world.
But the excessive commercial hunting has helped
its population decrease drastically and now has
posed a threat to its mere existence even though
an international ban was constituted in 1966.
MARINE HABITATS
Prevention and Conservation
•
Marine Protected Areas (MPAs): marine sites such as sanctuaries, fisheries
management areas, state conservation areas, and wildlife refuges established
to protect habitats, endangered species, and to restore the health of marine
ecosystems in areas jeopardized by habitat and species loss.
•
Marine Reserves: marine sites that provide a higher degree of ecosystem
protection by prohibiting fishing, mineral extraction, and other habitat-altering
activities. Marine Reserves are far more effective than MPAs, but unfortunately,
they are not as common.
•
Land use and development regulation: An integrated approach to land use and
management based on scientific knowledge is needed to protect coastal areas.
Policy makers need to be informed on the impact coastal development is
having on marine habitats through accessible and evidence-based information.
•
Monitoring and reporting: some conservation efforts are empowering the
citizens with the responsibility for monitoring water quality in their coastal
communities through sampling and testing, photographing fouled areas, and
providing information to local policy makers for action.
EFFECTS ON HUMANS
Habitat destruction vastly increases an area's vulnerability to natural
disasters like flood and drought, crop failure, spread of disease, and water
contamination.
Agricultural land can actually suffer from the destruction of the surrounding
landscape. Over the past 50 years, the destruction of habitat surrounding
agricultural land has degraded approximately 40% of agricultural land worldwide
via erosion, salinization, compaction, nutrient depletion, pollution, and
urbanization.
Humans also lose direct uses of natural habitat when habitat is destroyed.
Aesthetic uses such as birdwatching, recreational uses like hunting and fishing,
and ecotourism usually rely upon virtually undisturbed habitat. Many people value
the complexity of the natural world and are disturbed by the loss of natural habitats
and animal or plant species worldwide.
Across the globe, poor people suffer the most when natural habitat is destroyed,
because less natural habitat means less natural resources per capita, yet
wealthier people and countries simply have to pay more to continue to receive
more than their per capita share of natural resources.
THANK YOU
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