exam 2 chapter 4

Question 1

Invasive species

Answer 1

Introduced species that increas- es in abundance at the expense of native species.

historical slow threat, compete with active species.

Question 2

synergies of all these threats=

Answer 2

habitat loss

Question 3

deforestation=

Answer 3

right away kills tree

Question 4

7 threats to biodiversity

Answer 4

-There are seven major threats to biodiversity: habitat destruction; habi- tat fragmentation; habitat degradation (including pollution); global climate change; the overexploitation of species for human use; the invasion of exotic species; and the increased spread of disease

-Most threatened species and ecosystems face at least two or more of these threats, which can interact synergistically to speed the way to extinction and hinder efforts at protecting biodiversity (MEA 2005b; Burgman etal.2007).
- All seven threats are the result of an expanding human population’s ever increasing use of the world’s natural resources.

Question 5

Three ways in which humans dominate the global ecosystem

Answer 5

Three ways in which humans dominate the global ecosystem
1.LAND SURFACE
Human land use and need for resources have transformed as much as half of the Earth’s ice-free land surface.
2.NITROGEN CYCLE
Each year human activities, such as cultivating nitrogen-fixing crops, using nitrogen fertilizers, and burning fossil fuels, release more nitrogen into terrestrial systems than is added by natural biological and physical processes.
3.ATMOSPHERIC CARBON CYCLE
By the middle of this century, human use of fossil fuels will have resulted in a doubling of the level of carbon dioxide in the Earth’s atmosphere.

Question 6

Human population growth and its impacts
The major threats to biodiversity area all rooted in the

Answer 6

The major threats to biodiversity area all rooted in the expanding human population.

The greatest destruction of biological communities has occurred over the last 150 years.

During this time human population has increased from 1 billion in 1850 to 7 billions to now.

Question 7

The United States:

Answer 7

The United States:
It has 5% of world’s population

It uses roughly25% of the world’s natural resources

Each year the average US citizen uses 23 times more energy and 79 times more paper products that the average citizen in India.

Question 8

Impact of human population:

Answer 8

Impact of human population:
I=impact felt over a great distance, U.S. uses food, timber that come from other countries and this affects their environment
I = P x A x T
P= number of people
A= average income
T= level of technology
Globalization: Interconnectedness of resources and labor markets (leads to ecological footprint)
Ecological footprint: Influence a group of people has on both, the surrounding environment and location around the globe.

Question 9

Habitat destruction

Answer 9

Main threat to biodiversity
In US only 42% of natural vegetation remains
Certain biological communities have declined by 98% or more

Tropical Rain Forest-most threatened habitat
7% of Earth’s land
50 % of Earth’s species
1/3 has been destroyed
Remaining is being lost at 1% per year

Question 10

-loss of biodiversity is not directly caused by

Answer 10

-loss of biodiversity is not directly caused by human exploitation, it is a result of habitat destruction caused by humans

Question 11

main threat to biodiversity is

Answer 11

habitat loss and degradation, however synergy is also a problem

Question 12

hotspots=

Answer 12

high biodiversity, high threat, richness of species -complex interactions

Question 13

Rain forests also have

Answer 13

Rain forests also have regional importance in protecting watersheds and moderating climate, theyhavelocalsignificanceashomestonumerousindigenouspeoples,and they have global importance as potential sinks to absorb the excess carbon dioxide that is produced by the burning of fossil fuels.

Question 14

shifting cultivation

Answer 14

-slash and burn-> subsistence farming in which trees are cut down and then burned-> soil fertility also diminishes

-most destruction for cash crop plantations oil palm
No rainforests by 2050

Question 15

Increase in human population=

Answer 15

increase in need for agricultural land and output-> results in need to protect biodiversity in need to protect biodiversitity will compete directly against the need for new agricultural lands

Question 16

During the 80s

Answer 16

During the 80s Costar Rica and other Latin American countries had some of the world’s highs rates of deforestation

Conversion of rain forest in cattle ranches

• “Hamburger connection”-> areas in Costa Rica totally destroyed in order to sell beef-> mostly sold to u.S> for inexpensive hamburgers

Question 17

Tropical Deciduous Forest

Answer 17

Tropical Deciduous Forest
Easier than rain forest to clean and burn
Human population density is five times greater in this type of vegetation than in tropical rain forest.
The Pacific Coast of Central America has less than 2% of its original forest.
Less than 3% remains in Madagascar, home of lemurs.

long distance dry season, has a district rainy season
-loose their leaves in dry seasons
-more suitable for agriculture and cattle ranching
-nutrients retains in soil unlike rainforest

Question 18

lemurs

Answer 18

found in Madagascar are all endangered as a result of destruction of Madagascar forests
-only place where lemurs occurring wild
-eventually be extinct by 2020

Question 19

grasslands
wetlands

Answer 19

Grasslands
Easier than rain forest to clean and burn.
Between 1800 and 1950 98% of North America’s tall grass prairie was converted to farmland.
Worldwide only 4% of grasslands are protected.
Remaining is highly fragmented.
-almost completely destroyed by human activity
-easy to convert to farmland and cattle ranches
-“bread basket” area

Wetlands: habitats in which land and water meet
50 % of wetlands in US have been destroyed
98% of the streams in US have been degraded
60-70% of wetlands in Europe have been lost
Yangtze River, China: development projects
-important for wellbeing of fish, amphibians, birds
-waste reducing, water purification
-known for high levels of endemism-tendency of species found in these systems to be unique and not found anywhere else
China- three gorges dam-clean and renewalable energy -destroy biological communities and job

Question 20

Marine Coastal Wetlands

Answer 20

Marine Coastal Wetlands
More than 20% have been degraded or highly modified.
Pollution, dredging, sedimentation, destructive fishing practices, rising sea temperatures and water levels, growing acidity of ocean, and invasive species.
Mangrove and Coral reefs are in serious danger Remaining is highly fragmented.

Question 21

Mangroves
Coral reefs

Answer 21

Mangroves
High economical value: fish, shrimp.
Protect coastal areas from storms and tsunamis
35% of the world’s mangroves ecosystems have been destroyed.

Coral reefs
1/3 of ocean’s fish species in only 0.2% of its surface
20% have been destroyed.
Pollution, costal development, climate change.
-philipines-90% of coral reefs are dead or dying

Question 22

Desertification

Answer 22

Desertification
Human man deserts
9 million km2 of arid land have been converted to human made deserts.
Solution: improving sustainable agricultural practices, elimination of poverty, stabilization of civil society, and population control.

-seasonally dry climates, grasslands, tropical deciduous forests, temperate shrublands
-initially support Agriculture but repeated cultivation especially during dry and windy years leads to soil erosion and loss of capacity to hold water

Question 23

Habitat fragmentation
Edge effect:
Fragments vs original habitat:

Answer 23

Habitat fragmentation is the process whereby a large continuous area of habitat is both reduced in area and divided into two or more fragments.

Edge effect: Altered environmental and biological conditions at the edges of a fragmented habitat.

Fragments vs original habitat:
Have a greater amount of edge per area of habitat
The center of each habitat fragment is closer to an edge
Have smaller populations

Question 24

fragmentation almost always

Answer 24

Fragmentation almost always occurs during a severe reduction in habitat area, but itcan also occur ifhabitat area isonly minimally reduced, as when itisdivided by roads, railroads, power lines, fences, or any barrier that prevents animals from moving freely (Figure 4.8B).

Question 25

ex: reindeer affected by fragmentation

Answer 25

-last remaining pop. found in Norway
-used to be one continuous freely herd
-now because of fragmentation=26 herds unable to interact

Question 26

Habitat fragments differ from original in three ways

Answer 26

1. before- continuous habitat large pop.
   now- fragments of habitats-small pop.
2. have more edge per area of habitat fragmentation=greater exposure to edge effects
3. center of each fragment is closer to an edge

Question 27

Habitat fragmentation increases

Answer 27

It increases edge effects – changes in light, humidity, temperature, and wind that may be less favorable for many specie living there.

edge effects execrable problems of fragmented habitat

Question 28

Pollution

Answer 28

Pollution of the air, water, and soil by chemicals, wastes, and the by products of energy production destroys habitats in insidious ways.

-not immediate damage
-most subtleand universal form of environmental degradation
-affect human health as well not just species
-not visually apparent

Question 29

Pesticide pollution

Answer 29

Pesticide pollution
Biomagnification: magnification of concentration of pesticides as they ascend in the food chain.
DDT-rachel Carson, banned after research

-used to kill insects on crop plants, kill mosquitos by spraying on standing water, harms other life exposes them to dot birds who feed on fish in water lay thin eggs

Question 30

eutrophication, dead zones

Answer 30

Eutrophication Process of degradation in aquatic environments caused by nitrogen and phosphorus pollution and characterized by algal blooms and oxygen depletion
Dead Zones

in soil, runoff into river-> lake-> ocean. (algal blooms) block the sun-> no oxygen, algal blooms gets thicker, lower layers sink and die-> decomposers feed-> more nitrogen, no oxygen

Question 31

Air Pollution
Acid Rain
Ozone
Toxic metals

Answer 31

Air Pollution

Acid Rain is produced nitrogen oxides and sulfur oxides released in the air combine with moisture in the atmosphere: nitric and sulfuric acids.
-lowers the pH

Ozone(important in filtering out ultraviolet radiation) and photochemical smog is produced when hydrocarbons and nitrogen oxides react in the presence of sunlight.

Toxic metals leaded gasoline, mining and smelting operations, coal burned, etc., release lead, zinc, mercury and other toxic metals into the atmosphere.

Question 32

global warming
vs.
climate change

Answer 32

global warming-increase in temp.
climate change-humidity, wind patterns, precipitation. Involves everything. an average of conditions overtime

Question 33

greehouse gasses, greenhouse effect, global climate change

Answer 33

Greenhouse gases: Carbon dioxide, methane,
-gases that trap energy radiation from earth as heat, slowing rate at which heat leaves the earths surface and radiates back to space, good for warming earth- too much is bad

Greenhouse effect: Warming of Earth
-more gas, more heat, increases plants surface temp

Global warming: Increase of temperature from the greenhouse effect.

Global Climate Change: patterns on temperature, precipitation and wind that are changing now and will continue changing in the future.
- Intergovernmental Panel on Climate Change-study group of leading scientists agree that greenhouse gasses have increased worlds climate increase climate in the future
http://ipcc.ch/

Question 34

principle cause of destruction

Answer 34

habitat destruction

Question 35

Some evidence for global warming

Answer 35

Some evidence for global warming
2.MELTING OF GLACIERS AND POLAR ICE
Examples: Arctic Sea summer ice has declined by 15% in area over the past 25 years. Since 1850, glaciers in the European Alps have disappeared from more than 30-40% of their former range.
3.RISING SEA LEVELS
Example: Since 1938, one-third of the coastal marshes in a wildlife refuge in Chesapeake Bay have been submerged by rising seawater.
4.EARLIER FLOWERING OF PLANTS
Example: Two-thirds of plant species are now flowering earlier than they did several decades ago.
5.EARLIER SPRING ACTIVITY
Example: One-third of English birds are now laying eggs earlier in the year than they did 30 years ago, and oak trees are now leafing out earlier than they did 40 years ago.
6.SHIFTS IN SPECIES RANGES
Example: Two-thirds of European butterfly species studied are now found farther north by 35 to 250 km than recorded several decades ago.
7.POPULATION DECLINES
Example: Adelie penguin populations have declined by one-third over the past 25 years as their Antarctic sea ice habitat melts away.

Question 36

Overexploitation

Answer 36

Intense harvest of a resource or species that result in its decline or lost.

CITES: Convention on International Trade in Endangered Species. Protect species from further explotation.

Question 37

kyoto protocol

Answer 37

-commits its members to reduction in greenhouse gas emissions, U.S. not in agreement

Question 38

bush meat

Answer 38

meat from wild animals
-bush-meat crisis-extensive hunting of animals
eating apes and chimpanzees will increases disease

Question 39

illegal and legal wildlife trade

Answer 39

responsible for decline of many species

Question 40

Chinese overexploits

Answer 40

seahorses-use as a symbol of dragon for healing power, treaty foster and Vincent-protect seahoreses

Question 41

sustainable yield

Answer 41

-the greatest amount of resource that can be harvested each year and replaced through population growth without detriment to the population

Question 42

bycatch

Answer 42

organisms caught by accident and then discarded, or when habitats on seafloor are scoured by dredges and trawls

Question 43

exotic species

Answer 43

-species that are present outside their natural ranges because human activities have distributed species throughout the world, obscuring past regional differences.
-become invasive species if they establish themselves in new habitat, they increase in abundance out of the expense of native species and impact endangered species.

Question 44

we don’t know there’s invasive species until

Answer 44

its too late

Question 45

invasive species

Answer 45

An introduced species that increases in abundance at the expense of native species.
Compete
Alter habitat
Economical impact- can use a biological control but can become invasive (prickle pear example)
Islands-isolated habitat usually drive natives to extinction
Aquatic habitats-isolated habitat like islands, drive natives to extinction
-invasive species become dangerous since they don’t have their predators to control them
Exotic Vs. Invasive species

Question 46

genetic swamping

Answer 46

invasive species and native species reproduce, blurs identitity of distinct species

Question 47

control of invasive species
GMOS

Answer 47

Ability of species to become invasive

Control of Invasive species- train citizens to monitor vulnerable habitats-use biological control

Genetically Modified Organisms (GMOs)- gene transfer. In such organisms, scientist have added genes from a diff. species into the genetic code of GMO using recombinant DNA technology
-can harm non crop species such as insects, birds that live near agricultural fields

http://www.youtube.com/watch?v=mUssO68D2eM

Question 48

Disease

Answer 48

Increasing incidence of infectious disease threatens wild and domestic species as well as humans. Transfer of diseases between different species is a subject of special concern.

increase in habitat destruction= increase in susceptibility to disease
-introduced diseases can decimate (kill or destroy) even widespread and abundant species.