threats to biodivefsity

1. Hameedullah kakar

2.  Primary causes spell “HIPPO”:
◦ Habitat alteration
◦ Invasive species
◦ Pollution
◦ Population growth
◦ Overexploitation
 Biodiversity is a measure of the relative diversity
among organisms present in different ecosystems.

3.  The greatest cause of extinction today
 Accounts for 85% of population declines of birds
and mammals
 Habitat change hurts most organisms because
they are adapted to an existing habitat.
 Alteration due to:
 Forest clearing Urban development
 Agriculture Global climate change
etc….

4.  Accidental or intentional introduction of exotic
species to new areas
 Most do not establish or expand, but some do—
likely because they are “released” from
limitations imposed by their native predators,
parasites, and competitors.
 In today’s globalizing world,
 invasive species have become perhaps the second-
worst threat to native biota.

5.  Examples:
◦ Mosquito fish
◦ Zebra mussel
◦ Kudzu
◦ Asian long-
horned beetle
◦ Rosy wolfsnail
◦ Cane toad
◦ Bullfrog
 Gypsy moth
 European
starling
 Indian
mongoose
 Caulerpa algae
 Cheatgrass
 Brown tree
snake
Figure 15.10

6.  Air and water pollution; agricultural runoff, industrial
chemicals, etc.
 Pollution does serious and widespread harm, but is
not as threatening as the other elements of HIPPO.

7.  Human population growth exacerbates every
other environmental problem.
 Magnifies effects of the other elements of HIPPO:
 More people means more habitat change, more invasive
species, more pollution, more overexploitation.
 Along with increased resource consumption, it is
the ultimate reason behind proximate threats to
biodiversity.

8.  Two meanings:
 Overharvesting of species from the wild
 (too much hunting, fishing…)
 Overconsumption of resources
 (too much timber cutting, fossil fuel use…)
 Usually overexploitation is not the sole cause of
extinction, but it often contributes in tandem with
other causes.

9.  People are clearing forests to make
residential colonies, roads between and
within the cities and agriculture use.
 The wood which we gained by forests and
trees people used in building material,
furniture, paper products and is also used
in many rural areas as firewood. in our
rural areas people used this material for
different purpose.
 Deforestation is a real harm for our
ecosystem and environment.
 one of the major environmental issues, not only in directly affected
countries and locations, but also from a global prospective.
 Deforestation means the loss of forest due to overcutting of trees.
 The long term or permanent loss of forest and implies transfer into
another land use.
 Pakistan is included in one of those countries where deforestation
rate is extremely high.
 The main cause of deforestation in Pakistan is the constant increase
in population.

10.  Overgrazing represents an environmental hazard whereby wildlife or
livestock excessively feeds on pasture.
 It is also the practice of grazing livestock on vegetation before it has
recovered from a former grazing state, also known as intensive
grazing.
 Otherwise stated, overgrazing takes place when vegetation or
pasture is repeatedly removed from land and it is not given enough
time to continue growing.
 Intensive grazing thus causes the plant residual matter to decline
and further contributes to numerous negative consequences to both
the animals and the land.
 Consequently, overgrazing signifies a serious
environmental challenge in maintaining the
natural balance of livestock on grazing lands,
which reduces the productivity, usefulness,
and biodiversity of the land.
 The following are the causes, effects, and
solutions of overgrazing

11.  Soil is the earth’s fragile skin that anchors all life on Earth.
 It is comprised of countless species that create a dynamic and
complex ecosystem and is among the most precious resources to
humans.
 Increased demand for agriculture commodities generates incentives
to convert forests and grasslands to farm fields and pastures.
 The transition to agriculture from natural vegetation often cannot
hold onto the soil and many of these plants, such as coffee, cotton,
palm oil, soybean and wheat, can actually increase soil erosion
beyond the soil’s ability to maintain itself.

12.  Desertification is the persistent degradation of dryland
ecosystems by variations in climate and human activities. Home to a
third of the human population in 2000, drylands occupy nearly half
of Earth’s land area.
 Across the world, desertification affects the livelihoods of millions of
people who rely on the benefits that dryland ecosystems can
provide.
 In drylands, water scarcity limits the production of crops, forage,
wood, and other services ecosystems provide to humans.
 Drylands are therefore
highly vulnerable to increases in
human pressures and climatic
variability, especially sub-Saharan
and Central Asian drylands.
 Some 10 to 20% of drylands are
already degraded, and
ongoing desertification threates the
world’s poorest populations and the
prospects of poverty reduction.

13. 
Ecosystem services are the benefits obtained by people from ecosystems,
for instance crops, forage and wood. In drylands, water scarcity limits
the production of such services provided by ecosystems.
 Persistent, substantial reduction in the provision of ecosystem services as a
result of water scarcity, intensive use of services, and climate change is a
much greater threat in drylands than in non-dryland systems.
 Areas most vulnerable to desertification are the sub-Saharan and Central
Asian drylands.
 Desertification occurs as a result of a long-term failure to balance human
demand for ecosystem services and the amount the ecosystem can supply.
 The pressure is increasing on dryland ecosystems for
providing services such as food, forage, fuel, building materials, and water
which is needed for humans, livestock, irrigation, and sanitation.
 This increase is attributed to a combination of human factors (such as
population pressure and land use patterns) and climatic factors (such as
droughts). While the global and regional interplay of these factors is
complex, it is possible to understand it at the local scale.

14.  The introduction of non-native species into
an ecosystem can threaten endemic wildlife
(either as predators or competing for
resources), affect human health and upset
economies.
 What can we do? According to the National
Wildlife Federation, solutions include creating
systems to prevent introduction of invasive
species in the first place, effectively
monitoring for new infestations and swiftly
eradication newly detected invaders

15.  From the burning of fossil fuels (releasing dangerous
chemicals into the atmosphere and, in some cases,
depleting ozone levels) to dumping 19 billion pounds of
plastic into the ocean every year, pollution completely
disrupts the Earth's ecosystems.
 While it may not necessarily cause extinction, pollutants
do have the potential to influents species' habits.
 For example, acid rain, which is typically caused by the
burning of fossil fuels, can acidify smaller bodies of water
and soil, negatively affecting the species that live there
by changing breeding and feeding habits.
 What can we do? The average person can do a number of
things to fight atmospheric and hydrologic pollution, such
as recycling, conserving energy at home and using public
transportation.

16.  Changes in climate throughout our planet's history have, of
course, altered life on Earth in the long run — ecosystems have
come and gone and species routinely go extinct.
 But rapid, manmade climate change speeds up the process,
without affording ecosystems and species the time to adapt.
 For example, rising ocean temperatures and diminishing Arctic
sea ice affects marine biodiversity and can shift vegetation
zones, having global implications.
 Overall, climate is a major factor in the distribution of
species across the globe; climate change forces them to adjust.
But many are not able to cope, causing them to die out.
 What can we do? Individuals can take various steps to fight
climate change, such as reducing their carbon footprints,
promoting education and contacting elected officials..
 International governments and cities can lead the charge,
however, and the 2015 United Nations Climate Change
Conference in Paris will hopefully be a turning point.