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Green Earth
Exam 3
34
Science
Undergraduate 2
12/02/2009

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Term
What are the human factors relating to decreased biodiversity?
Definition
Habitat loss, degradation, invasive species, hunting/poaching/overfishing, sale of exotic species, pollution climate change
Term
What are invasive species, and how do they affect biodiversity?
Definition
Invasive species are non-indigenous species that can affect biodiversity by outcompeting indigenous species, hybridizing with indigenous species thus removing them from the ecosystem, and genetic pollution.
Term
What example of human factors does the passenger pigeon represent?
Definition
The passenger pigeon represents human overhunting, which eventually lead to the bird's extinction, and therefore a decrease in biodiversity.
Term
What are some of the utilitarian uses of biodiversity that humans depend on?
Definition
economic goods such as food, fuel, fiber, lumber and MEDICINE, photosynthesis, pollination of crops, soil maintenance, nutrient recycling, detox. Basically, the diverse organisms in ecosystems are responsible for keeping them stable, and with a decreased variety, agriculture, health, recreation and research industries could be affected.
Term
What do the non-intrinsic uses of biodiversity relate to?
Definition
the value in existence, and aesthetic beauty found in a diverse ecosystem.
Term
What are the three key ways of measuring biodiversity?
Definition
1)GENETIC DIVERSITY 2)SPECIES DIVERSITY 3)ECOSYSTEM DIVERSITY
Term
What are the three key ways of measuring species diversity?
Definition
1) SPECIES RICHNESS (population density) 2)SPECIES ABUNDANCE (how many different species are there?) 3) TAXONOMIC DIVERSITY (how related are the species?)
Term
What changes can be seen in species diversity, geographically?
Definition
Closer to the equator: MORE diversity, decreased elevation: MORE diversity, deeper in the see down to 2000m: MORE diversity
Term
Where are some of the most species rich environments?
Definition
tropical rainforests and lakes, the deep sea and coral reefs
Term
What are the four key types of species in an ecosystem?
Definition
Native, non-native, keystone, and indicator
Term
What is an indicator species, why is it important to an ecosystem, and which species usually play this role?
Definition
Indicator species are species that show early warning of ecosystem damage. They are important because they are the first to exhibit response, and are very sensitive to change. This can help monitoring biologists to take precautions in the event of a change. Decline in bird and fish species usually signifies a effective habitat loss, or water pollution.
Term
What is a keystone species, and why is it important to the ecosystem?
Definition
A keystone species has a disproportionate effect on its environment relative to its abundance. These species affect many other organisms in an ecosystem and help to determine the types and numbers of various others in a community. THese include: PREDATORS (population control), MUTUALISTS(pollination), ENGINEERS(habitat modification).
Term
What are the 3 key ways to measure extinction rates?
Definition
Minimum viable population estimates, minimum dynamic area, and population viability analysis (risk assessment)
Term
What does minimum viable population refer to?
Definition
the minimum population number to ensure the survival of a species in a certain time and area. Usually involves a few thousand individuals.
Term
What does minimum dynamic area refer to?
Definition
The minimum area of sustainable habitat to sustain the minimum viable population.
Term
What does population viability analysis refer to?
Definition
Population viability analysis is a sort of risk assessment, based on reproduction rates, interactions with other species, genetic variability, and resource needs to analyze the viability (mainentance) of a species.
Term
What are the three key types of extinction?
Definition
1)Local extinction: species extinct from a local area. 2)ecological extinction: so few exist, they have no role in ecosystem. 3)biological extinction: gone.
Term
What characteristics make species prone to extinction?
Definition
Low reproductive rates, special niches (habitats), commercial value, narrow distribution
Term
What outside stressors can lead to species extinction?
Definition
environmental stress, large disturbances, extreme conditions, resource limitations, invasive species
Term
Within an ecosystem are communities. What does this refer to?
Definition
An ecosystem refers to all of the organisms in a specific place, and the environment with which they interact. communities is more specific, and refers to the different populations of species found in the ecosystem.
Term
What are autotrophs and why are they important?
Definition
Autotrophs are primary producers: they capture energy from the environment by way of chemo and photosynthesis. They are important because they convert the energy into substances that heterotrophs can process.
Term
What are the 3 trophic levels, and how do they interact?
Definition
1st: primary producers (autotrophs) 2nd: primary consumers (herbivores) 3rd: secondary consumers. These trophic levels are important because they are what essentially form the food chain.
Term
What is succession? what are the three stages of succession?
Definition
succession refers to the change that ecosystems experience over time. the first stage is induced by the pioneer species: the first to move in and colonize. The climax stage is the most stable stage of the ecosystem. secondary succession is the effect of a disturbance.
Term
How many mass extinctions were there, and how many species were wiped out?
Definition
5, and 50%
Term
What was the Lacey Act of 1900 and why was it important?
Definition
the lacey act prohibited any transport of any wild animal, dead or alive, across a state border, It was important because it protected wildlife.
Term
What is the endangered species act?
Definition
The endangered species act protected endangered species so that they could not be hunted or killed, also promoting habitat protection and recovery plans.
Term
CITES
Definition
stopped trading of endangered species, hard to enforce, small fines.countries can exempt themselves.
Term
What is the sanctuary approach to wildlife conservation?
Definition
This approach attempts to set up habitats for species in which they can thrive. Old military bases, as well as zoos and parks are potential places for these sanctuaries. NATIONAL WILDLIFE REFUGE SYSTEM
Term
What are some of the approaches used in zoos and aquariums to ensure the protection of species?
Definition
captive breeding programs, AI
Term
Even aged vs. Uneven aged management of trees
Definition
even: same age and size plantations. Uneven: maintain variety of sizes, selective cutting, long term sustainability
Term
What are the 5 main harvesting techniques for loggers?
Definition
1)build a logging road, 2)clear cutting 3) selective cutting, 4)shelterwood cutting (remove older treas in 2 cuttings over 10 years), seed-tree cutting
Term
Soltuions to deforestation
Definition
use of alternative fuels other than wood. maintain sustainable agroforestry: multilayered cultivation, strip cut forests with LONG cycles.
Term
What does the US currently do to maintain diversity?
Definition
long rotations, selective cutting, strip cutting, minimize fragmentation, reduce road building, leave dead trees
Term
What are some of the main factors of an ecostystem to consider when trying to decide how to manage it?
Definition
shape(circular is best), size(one large vs. many small), heterogeneity(is it all the same? sustainable?), bufferzones(to protect interior).
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