chapter 11,12,13 EXAM Flashcards
exotic species
organisms that live outside their historic range
ex:
- zebra mussels
- silver carp
invasive species: organisms that spread quickly across and area (one f the causes of the 6th mass extinction)
clear cutting
removing all the trees from an area in a single cutting
pros:
- easy to harvest
- most economic way to harvest
- trees grow back fast bc they are the same species
cons:
- fragmentation
- less biodiversity (same species tree)
- loss of soil nutrients
- increase water temperature
- herbicides are used before replanting
biosphere reserves
protected areas consisting of zones that vary in the amount of permissible human impact
maximum sustainable yield
-the amount of a renewable resource that can be harvested w/o compromising the future availability of the resource
( y-axis: pop. size , x-axis: time )
endangered species act (1973)
authorized the U.S fish and wildlife service to determine which species can be listed as endangered and prohibits the harming and trading of these species.
-organisms such as the gray wolf was benefited from this act
CITES
CONVENTION ON INTERNATIONAL TRADE IN ENDANGERED SPECIES
- an international agreement between 175 countries
- developed in 1973
problems:
- not everyone signed it
- no standard enforcement of punishment fro not following
- some countries do not have enough money to enforce
first national park in U.S?
yellowstone national park
national parks
managed for scientific, educational or recreational uses
-fishing, hiking, camping, boating, mining and oil drilling
-managed by the national park service (NPS: manages for ecosystems)
national forests
- used for logging, mining, livestock, grazing, farming, recreation, conservation and oil and gas extraction
- managed by the U.S forest service
wildlife refugee
- protect habitats and breeding areas but are also used for hunting, fishing, mining, logging and farming.
- managed by the U.S fish and wildlife service
national wilderness areas
-set aside land to preserve tracts of intact ecosystems or landscapes
- managed by the U.S wilderness society
- most areas in the U.s are loaded in the western states (California, Oregon, Washington)
fire management
-suppressing forest fires could lead to a build-up of undergrowth and liter, which if caught on fire, will cause more damage then if the fuel supplies were low.
controlled / prescribed burns: a small fire that is purposely set when conditions are just right in order to keep fuel supplies low
country w the highest deforestation rate?
-malaysia, indonesia or brazil
type of organisms going extinct
(in order from most to least threaten w extinction)
- fish
- mammals
- reptiles
- plants
- birds
forest fragmentation
- when a forest area is reached and divided into smaller patches. this also divides the organisms into smaller groups.
- species become more vulnerable to extinction when this happens
debt-for-nature
finical transaction in which a portion of a developing foreign nation’s debt is forgiven in exchange fro local investments in environmental conservation measures.
seed and gene banks
- preserve genetic biodiversity in a species
- store seeds as a source for future planting
- seeds may be from a rare species or accent varieties of seeds not used in commercial processing
cons:
- expensive to operate
- seeds may not survive in the further environment
botanical gardens
- conservation of plant species
- used for research and to educate people about plant con.
cons:
- have little storage capacity
- too little funding
arboreta
a place where an extensive variety of woody plants (trees) re cultivated for scientific or educational purposes.
zoos
-used as captive breeding sites, conserving rare and endangered species and used for public education
cons:
- animals that are kept in captivity usually don’t survive once put back into the wild
- organisms got through abuse from visitors
biodiversity hot-spot
a biogeographic region that is both a significant reservoir of biodiversity and is threatened with destruction.
urban, suburban and rural areas
- most if the U.S population lives in SUBURBAN areas
- the populations were equal in all three in the 1960s
- greatest overall growth rate: SUBURBAN
yellowstone national park: gray wolves
w/o wolves:
- overgrazing due to increased elk, moose and antelope populations
- major soil erosion
- threatened niches
with wolves:
- decreased (back to stable) elk, moose and antelope populations
- more beavers returned to ecosystem
- grizzly bear population grew
- aspen and willow tress started to grow back
BLM lands
- natural resource lands used for mining, oil and gas extraction and livestock grazing
- managed by the BLM AKA the bureau of land management
