Biodiversity Chapter 9

4/7 major threats to biodiversity in chapter 9

• Habitat destruction

• Habitat fragmentation

• Habitat degradation

• Global climate change

Human Activities that cause threats include

• Agriculture

• Logging

• Fisheries

• Industry and fossil fuel use

• Urbanization and road construction

• International trade

Results of human activities

• Loss of biodiversity

• Extinction of species in populations

• Degradation of ecosystems

• Erosion of genetic Diversity and evolutionary potential

• Loss of ecosystem services

• Erosion of support systems for human societies

Three ways humans dominate the global ecosystem

1. Land surface

2. Nitrogen cycle

3. Human use of fossil fuels And deforestation

Human domination through land surface

• Human resource needs and land use, mainly agriculture And forestry, have transformed as much as half of the earths ice free land surface

Humans Domination through the nitrogen cycle

• Each year human activities release more nitrogen into terrestrial systems than is added by natural biological and physical processes

Human domination through use of fossil fuels and deforestation

• By the middle of the century, this will have resulted in a doubling of the level of carbon dioxide in the earths atmosphere

In the last 164 years, the population has increased from 1 billion to

• 8.2 billion people

The increase from 1, billion to 8.2 billion people is

• The route to destruction of biodiversity

Globalization

• The increasing interconnectedness of natural resources and labor markets

Ecological footprint

• The influence of a group of people on the surrounding environment and locations across the globe

Greatest threat to All of the worlds species

• Habitat loss and degradation

Mammal’s greatest threats following habitat loss and degradation

• Over exploitation

• Intrinsic Factors

Bird’s greatest threats following habitat loss and degradation

• Overexploitation

• invasive species

Amphibian’s greatest threat following habitat loss and degradation

• Pollution

• Intrinsic factor

• Disease

Gymnosperms greatest threats following habitat loss and degradation

• Over exploitation

• Intrinsic factors

Intrinsic factors

• Aspects of species biology such as behavior

Habitat destruction

• the process by which a natural landscape is altered or cleared to the point that it can no longer support its native flora and fauna

Percent of land that is suitable on earth for farm/agriculture already been converted

• 98%

What can we do to meet the population increase demand for food?

• Increase crop out

• Changed the way we purchased items

• Change our throwout mentality

Tropical moist/rainforest occupy ____ of the Earth surface

• 7%

Tropical moist/rainforest our home to ______ of the Earth species

• >50%

____ of the tropical rainforest are in the Brazilian Amazon

• 40%

Rainforest to remain in 2050

• New government policies

• Stricter enforcement of logging regulations

Shifting cultivation//and burn agriculture/swidden agriculture

• This technique is about cutting and burning then plant crops into the soil is no longer

• Field is abandoned and new patches are cut and burned

Examples of displacement of rainforest for agricultural purposes

• Indonesia

• Malaysia for mono culture, such as oil palm

• Forest cleared in Rondonia from 1985 to 2001

Major monocropping products

• Coffee

• Chocolate

• Palm oil

• Soy beans

• Meat products

• Citrus products

• Timber

Indonesian Borneo and Sumatra in Southeast Asia

• 42% of Forest cleared between 1990 and 2005

• Cash Crops , such as Palm oil

Animals affected by Palm oil

• Orangutan

• Sumatran rhino

• Sumatran tiger

• Proboscis monkey

• Clouded leopard

• Sun bear

• Flathead cat

• Big cat

• Malaysian tapir

• Asian elephant

• Gibbon

• Fishing cat

Endangered and vulnerable species due to palm oil production

• Cotton top monkey

• Chimpanzee

• African forest elephant

• Tiger

• Orangutan

• Gibbon And sun bear

• Tree kangaroo and cassowary

Why palm oil producers looking for other customers and lowering their prices doesn’t work

• Increase demand for Markets which have less interest in sustainability

• Reduce reduces the incentive to produce environmentally sustainable palm oil

Why having companies use alternative oils doesn’t work

• Other oils use up to nine times as much land as palm oil

• Increases natural habitat loss, species loss and other impacts

Attainable goals for decreasing destruction

• Locally grown resources

• Home gardens

• Sustainable development

• Polycultures

• Reduce reliance on meat and meat products

Other threatened habitats

• Tropical deciduous forest

• Grasslands

• Wetlands

• Mangroves

• Coral Reefs

Tropical deciduous forest

• Regions with heavy rainfall for part of the year, followed by a marked dry season

• Average temperature is about 50°F

• Dense and lush during wet summers

• Dry during dry winters where trees shed their leaves

Why are tropical deciduous forests so appealing as areas for development?

• Land more suitable for agriculture and cattle ranching

• Land easier to clear and burn

• Human population density greater compared to rain forests

Example of tropical deciduous forest vulnerability

• Pacific coast of Central America has only 2% remaining

Example of animal affected by habitat destruction of tropical deciduous forest

• Indri lemur

• Primate found only on Madagascar

Grasslands

• Areas where vegetation is dominated by grasses

• Sedge, rush, and legumes can be found

• Occur naturally on all continents except Antarctica

Why are grasslands Threatened?

• Almost completely destroyed by human activity

• Easy to convert to farmland in cattle ranches

• Only 4% are protected worldwide

____ of North America’s Prairie have been converted to farmland

• 98%

Wetlands

• distinct ecosystem that is flooded by water either permanently or seasonally

• Oxygen free processes prevail

• Characteristic vegetation of aquatic plants adapted to the unique hydrate soil

Examples of wetlands

• Marsh

• Swamp

• Bog

• Fen

• Mangrove

Why are Wetlands important?

• Habitat for fish, birds, reptiles

• Flood control

• Drinking water

• Power production

• Carbon sink

Why are wetlands appealing for development?

• Can be filled in or drain

• Can be altered with channels for shipping goods

• Are in Areas of high human density

Over last 200 years more than ____ of the wetlands in the US have been destroyed

• Half

Louisiana has maintained ___ of the wetlands in the US

• 42%

San Diego country Wetlands

• More than 97% of the vernal pools have been destroyed

Wetlands in Europe

• 60 to 70% have been lost

Japanese Wetland

• Only two of their 30,000 rivers are without dams or other major modifications

Mangroves

• groups of trees and shrubs that live in Coastal intertidal zone

• About 80 different species of trees

• Trees grow in areas with low oxygen soil

• Slow moving waters, allow settlements to accumulate and have brackish to saline water

Why are mangroves important?

• Habitat for fish, birds, reptiles, manatees

• Important breeding ground for shrimp and fish

• Flood protection from tsunami’s

• Carbon sinks

Why are mangroves appealing for development?

• They can be converted for race cultivation

• Developed into shrimp and prawn hatchery

• Are in area areas of high human density

• Humans over harvest their wood

Habitat destruction endangered species for mangroves

• Manatees

• Tigers

• Sloths

• Proboscis Monkey

Coral reefs

• Underwater ecosystem

• Rebuilding corals from colonies of coral polyps Held together by calcium carbonate

• A.k.a. rainforest of the sea

• Species rich with fish, Mollusk, Worms, crustaceans, echinoderm, sponges, sea turtles, and sharks

Why Are coral reefs important?

• Home to 1/3 of the ocean’s fish

• Important feeding grounds with many invertebrates and vertebrates

• Carbon sink

Why are coral being destroyed or degraded?

• Destroyed by explosives during over fishing and over harvesting

• Zooxanthalle can’t withstand warmer water temperatures associated with global warming

___ of Coral reefs have already been destroyed

• 20%

Coral reefs in the Philippines

• 90% are dead or dying

• Most severe location of destruction

Desertification

• Seasonally, dry, climates and communities that are susceptible to human destruction and degradation

• Turned into full-blown deserts

Climates susceptible to desertification

• Grasslands

• Shrub lands

• Deciduous forest

Habitat suffering from desertification do not function as deserts

• Become wasteland, lacking flora and fauna

• Soil degraded, and land can’t support the growth of resources

Places with high vulnerability to desertification

• Western United States

• Eastern Brazil

• Middle of Africa

• Spain

• Iraq

• Iran

• India

• Part of Australia

Habitat fragmentation

• Process whereby a large continuous area of habitat is both reduced in area and divided into two or more fragments

• Patchwork of fragments are left behind

Edge effect

• Edges of fragments and land experience severely altered set of conditions

• Reproduction and adaptation to new environment extremely difficult

Example of edge effect

• SE Asia 1970 to 1990

Palm oil habitat fragmentation Example

• Sumatra over last 100 years

Colorado habitat fragmentation

• 1957 to 1994

Wood thrush

• 20% chance of sighting in small forest fragments

• 80% chance of sighting in large block of Forest

How does habitat fragmentation affect populations?

• Limits dispersal and colonization

• Division of populations

• Restricts access to food and mates

Habitat fragmentation limits dispersal and colonization

• Birds, mammals and insects won’t cross open space even for a short distance

• Susceptible to predation

• Animals attempting to crossroads often to come to death from cars

Habitat fragmentation causes divisional populations

• Species can be subdivided and become vulnerable to inbreeding

Habitat fragmentation restricts access to food and Mates Examples

• Fragmentation breaks up area for Gibbons to forage for fruits

• Fences prevent migration patterns of wildebeest and bison

• Plants produce less seeds if butterflies and bees can’t migrate to pollinate

Edge effects can also include the following:

• Changes in micro climates

• Increased incidents of fire

• Increased vulnerability of species invasion

• Increase susceptibility to disease

Changes in micro climate effects:

• Amphibians like frogs, salamanders, toads and newts

Edge effects can cause these disease:

• Black leg tick disease

• Lyme disease

Reindeer in southern Norway

• Formally roamed throughout the mountains with only one break in the range

• Now has 23 isolated self populations

• Tend to keep 5 km away from humans

Examples of habitat degradation

• Pesticide pollution

• Water pollution

• Air pollution

Rachel Carson

• Book called Silent Spring

• Pesticide pollution by DDT

• Affecting hawks, eagles, fish, dolphins, polar bears, and farm Workers and people consuming seafood

Water pollution

• Runoff of pesticides, herbicides, oil, products, heavy metals, detergent, PCBs, industrial waste, and Pharmaceuticals

USA threatened by water pollution

• 90% of endangered fish and freshwater muscles

pharmaceutical water pollution effects

• With hormones negatively affect Fish physiology and reproduction

Mercury accumulation effects in water

• Seen in swordfish, shark, tuna

Eutrophication

• Process of degradation and aquatic environments caused by nitrogen and phosphorus pollution

• Characterized by algal blooms and oxygen depletion

• Create dead zones, where only species who can adapt to polluted waters and low oxygen survive

Air pollution effect on trees

• Makes them more susceptible to attack by insects, fungi, and disease

Flora sensitive to air pollution

• Lichens and mosses

Acid rain

• Produced an industries release Huge quantities of nitrogen and sulfur oxide into the air

• Causes tree deaths, increases toxins in aquatic systems, decreasing fish production and killing amphibians

pH range safe for most fish

• 5 to 9

pH of acid rain

• 2 to 5

Air pollution from 1990s to 2011

• improving pollution controls, creating cleaner burning fuels, and reducing economic activity

• Lower levels of acid rain

Photochemical smog

• Ozone and secondary chemicals produced when hydrocarbons and nitrogen oxide released from automobiles, power plants, and industrial activities are present with sunlight and react with the atmosphere

• Severe in China and Asian countries

Toxic metals

• lead

• Zinc

• Mercury

Activities that produce toxic metals

• Use of leaded gasoline

• Mining

• Smelting operations

• Coal burning industry

Greenhouse gases

• Gases in the atmosphere that are transparent to sunlight, but that trap near the Earth surface

• Primarily carbon dioxide and water vapor

greenhouse effect

• Warming of earth by greenhouse gases in the atmosphere that allows the sun’s radiation to penetrate and warm earth trapping heat near the surface, raising the planets temperature

Global warming

• Current and future increases in temperatures caused by higher levels of greenhouse gases produced by human activities

Global climate change

• Climate characteristics that are changing now and will continue to change in the future

• Resulting apart from human activity

Intergovernmental Panel on Climate Change (IPCC)

• Group of leading sciences, organized by the United Nations to study the impact and implications of human activity on climate and ecosystems

Carbon dioxide into the atmosphere do the human activities

• 70,000,000 tons

Evidence for global warming

1. Increased temperatures and heat waves

2. Melting of glaciers and polar ice

3. Rising sea levels

4. Earlier spring activity

5. Shifts in species ranges

6. Population declines