Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
115 Cards in this Set
- Front
- Back
What are the 9 terrestrial biomes?
|
1. tropical moist forest
2. tropical seasonal forest 3. tropical savannas and grasslands 4. deserts 5. temperate grasslands 6. temperate shrubland 7. temperate forest 8. boreal forest 9. tundra |
|
tropical moist forest
|
warm and wet year-round
|
|
tropical season forest
|
annual dry seasons
|
|
tropical savannas and grasslands
|
dry most of the year
|
|
deserts
|
hot or cold but always dry
|
|
temperate grasslands
|
rich soils
|
|
temperate shrublands
|
summer drought
|
|
temperate forest
|
evergreen or deciduous
|
|
boreal forest
|
lie north of the temperate zone
|
|
tundra
|
can freeze in any month
|
|
what environmental conditions control their distribution
|
temperature and precipitation
|
|
How does vertical stratification differentiate life zones in oceans?
|
Vertical stratification is a key feature of aquatic ecosystems. Light decreases as it gets lower, it depends on the temperature and oxygen amount to figure out which organisms can survive in the different zones
|
|
Why are coral reefs, mangroves, estuaries, and wetlands biologically important?
|
Because they have incredible diversity and help stabilize shorelines and they also provide critical nurseries for marine ecosystems.
|
|
What do we mean by biodiversity
|
Biodiversity is the number and variety of species in the ecosystem they occupy.
|
|
What are several regions that have high biodiversity
|
Yellowstone, Mt. Whitney, rain forests, coral reefs
|
|
What are four major benefits of biodiversity
|
All of our food comes from other organisms, rare species provide important medicines, biodiversity can support ecosystem stability, and has authentic and cultural benefits
|
|
What are the major human-caused threats to biodiversity
|
Extinction, habitat destruction, fragmentation reduces habitat, invasive species, pollution, human population growth, overharvesting and commercial collection (hunting and fishing), and predator and pest control
|
|
How can we reduce threats to biodiversity
|
Hunting and fishing laws protect reproductive populations, the endangered species act protects habitat and species
|
|
What portion of the world’s original forests remain?
|
Less than 10%
|
|
What activities threaten global forests?
|
overpopulation and deforestation
|
|
What steps can be taken to preserve the forests?
|
forest protection and watching the population size
|
|
Why is road construction a challenge to forest conservation?
|
they want to tear down the forests to build roads
|
|
Where are the world's most extensive grasslands?
|
The Great Plains and the Prairie Provinces in Canada
|
|
How are the world's grasslands distributed?
|
Grasslands are attractive for human occupation and are frequently converted to cropland, urban areas, and other human dominated landscapes
|
|
What activities degrade grasslands?
|
overgrazing
|
|
What are the original purposes of parks and nature preserves in North America?
|
Provides natural space for recreation and to preserve natural environments
|
|
What is a wilderness?
|
where animals are free, where they can roam
|
|
Why are wilderness areas both important and controversial?
|
Important because animals need to have natural habitats, controversial because they can extend into areas that have been urbanized and can hurt themselves and hurt others
|
|
What are some steps to help restore natural areas?
|
a.To maintain essential ecological processes and life-support systems (such as soil regeneration and protection, nutrient recycling, and water purification) on which human survival and development depend
b.To preserve genetic diversity essential for breeding programs to improve cultivated plants and domestic animals c.To ensure that any utilization of wild species and ecosystems is sustainable |
|
What are two goals of conventional agriculture?
|
maximize production and maximize profit
|
|
Soil Layers
|
O, A, E, B, C, R
|
|
O Horizon
|
humus
|
|
A Horizon
|
topsoil
|
|
E Horizon
|
eluviation layer
|
|
B Horizon
|
subsoil
|
|
C Horizon
|
regolith
|
|
R Horizon
|
bedrock
|
|
Monoculture
|
large scale farming--industrial approach to maximize output, minimize input and promotes intensive cultivation
|
|
Intensive cultivation
|
inorganic fertilization, irrigation, chemical control of weed/insects pests, and specialized plant varieties
|
|
Synthetic fertilizer
|
low cost, poor long-term soil fertility, and leaching into groundwater contamination and eutrophication
|
|
Irrigation
|
water is limited, impact on regional hydrology, borrowing water from the future, taking water from urban populations and wildlife, leaches fertilizers and chemicals from fields, and soil erosion
|
|
Chemical Pest and Weed Control
|
-Revolutionized agriculture after WWII
-Created a ‘pesticide treadmill’ -Total crop losses have not been decreased in long term -Pollution of groundwater and contamination of food chain |
|
Manipulation of Plant Genomes
|
-Traditional Ag also manipulated genomes
-Hybrid seeds greatly increased yields (Require optimal management and can’t produce seeds for next year) -GMOs are becoming a possibility |
|
Why Conventional Ag is not sustainable
|
-Present vs. future—conflict of interest (affluence vs. stewardship)
-Green revolution has petered out & grain reserves are shrinking -Pressure of food supply weakens stewardship -Resources (soil, water & genetic diversity) are shrinking |
|
Number of wild genes is decreasing
|
-Less chance to respond to changing environment
-Less chance to respond to new pests |
|
Loss of local control of Agriculture
|
Increases short-term goals, decreases stewardship
|
|
Sustainability =
|
change
|
|
Key elements to Sustainability
|
-Minimize negative impacts
-Preserve soils and their fertility -Conserve water -Use resources locally and renewably -Conserve biological diversity -Education of all producers world-wide |
|
Stability is an emergent property
|
Equilibrium and steady-state
|
|
Ecosystems
|
-External energy source, but use confined to trophic pyramid.
-Nutrients stay in -Populations reproduce themselves -Self-sustaining |
|
Agroecosystems
|
-External energy source, but biomass is removed
-Macro- and Micro-nutrients are exported and used up -Population depends on external supply of energy, seed and nutrients -Dependent on human control (stewardship?) |
|
What happens if forest is used for producing crops?
|
won’t last very long because there’s not enough organic crops, we’ll lose the forest because we’ll be cutting it down
|
|
Logging of tropical rainforest?
|
Strip-cutting, clear cutting, selective cutting—trying to get away from clear-cutting because the soil erodes; selective is the best, but more difficult to do.
|
|
Burning of temperate forest?
|
They are natural, burns all the dead stuff and new stuff grows
|
|
Will an abandoned Nebraska Farmstead return to tall-grass prairie?
|
No, after a long time maybe but not right away, will turn into weeds
|
|
a specific biological community and its physical environment interacting in an exchange of matter and energy.
|
Ecosystem
|
|
When a variety of species are present in such an ecosystem, the consequent actions of these species can affect the lives of fellow species in the area, these factors are deemed
|
Biotic Factors
|
|
are essentially non-living components that effect the living organisms of the freshwater community.
|
Abiotic factors
|
|
all members of a species that live in the same area at the same time.
|
Population
|
|
a bunch of different species living in a certain area/species diversity
|
community
|
|
properties that make a system more than the sum of its parts.
|
emergent properties
|
|
the number of species present in a community (species richness), as well as the relative abundance of each species.
|
diversity
|
|
an organism that synthesizes food molecules from inorganic molecules by using an external energy source, such as light energy.
|
autotroph
|
|
an organism that is incapable of synthesizing its own food and, therefore, must feed upon organic compounds produced by other organisms.
|
heterotroph
|
|
an organism that lives in or on another organism, deriving nourishment at the expense of its host, usually without killing it.
|
parasite
|
|
organisms that consume organic litter, debris, and dung.
|
detrivore
|
|
in ecological terms, a dynamic equilibrium among the physical and biological factors in an ecosystem or a community; relative homeostasis.
|
stability
|
|
stability=steady state or
|
dynamic equilibrium
|
|
synthesis of organic materials (biomass) by green plants using the energy captured in photosynthesis.
|
primary productivity
|
|
the nitrogen that plants can use, that legumes make- soybeans
|
'fixed' nitrogen
|
|
most important nutrients , need more of these-N, P, K, Ca, Mg, S
|
macronutrients
|
|
important, but don’t need as many-B, Fe, Mn, Zn, Cu, Cl, Mo, Ni, Se
|
micronutrients
|
|
the land that was either disturbed or land that has never been lived upon that now has organisms living on it
|
sucession
|
|
the top
|
climax
|
|
2 1/2 acres
|
hectare
|
|
How have global food production and population changed?
|
They've both increased
|
|
How many people are chronically hungry?
|
1 in 8.
|
|
Why does hunger persist in a world of surpluses?
|
Because the food does not get distributed evenly, famines, malnourishment
|
|
What are some health risks of undernourishment, poor diet, and overeating?
|
goiters, obesity, and diabetes
|
|
What are our primary food crops?
|
corn, rice, soybean, wheat
|
|
Describe five components of soil.
|
-Air
-Water -Soil fauna -Humus -Silts/clays -Sand/gravel |
|
What was the green revolution?
|
Started in 1970, improved crop varieties, increased fertilization, irrigation, and pesticide use.
|
|
What are GMO's?
|
genetically modified organisms
|
|
what traits are most commonly introduced with GMO’s?
|
pest resistance
|
|
Describe environmental costs of farming
|
soil erosion
|
|
ways we can minimize environmental costs
|
counterplowing, strip-cropping, terracing
|
|
Explain how soybeans grown in Brazil are improving diets in China.
|
The soybeans are being sent over to China to be fed to the livestock in China, they are benefitting from eating the animals that eat the soybeans. Because meat is the most nutritious.
|
|
Why do nutritionists worry about food security?
|
because of GMO's-they don’t know all the health risks that might come from them
|
|
Who is most likely to suffer from food insecurity?
|
anybody that eats GMO’s
|
|
What three crops provide most human caloric intake?
|
wheat, corn, soybeans
|
|
How can agriculture be sustainable if it causes erosion?
|
Different farming practices, terraces, counterplowing, strip-cropping
|
|
How has agriculture managed to keep up with population growth since 1960?
|
GMO’s, fertilizer, pesticides, made more land by cutting down forests
|
|
With so many choices for food, what strategy can you use for healthy eating?
|
Harvard food pyramid- healthy diets, exercise
|
|
the ability of individuals to obtain sufficient food on a day-to-day basis.
|
food security
|
|
acute food shortages characterized by large-scale loss of life, social disruption, and economic chaos.
|
famines
|
|
a nutritional imbalance caused by lack of specific dietary components or inability to absorb or utilize essential nutrients.
|
malnourishment
|
|
feeding large numbers of livestock at a high density in pens or barns.
|
Confined Animal Feeding Operation (CAFO)
|
|
the A horizon in a soil profile; the soil just below the litter layer.
|
Surface Soil
|
|
a layer of soil beneath the topsoil that has lower organic content and higher concentrations of fine mineral particles; often contains soluble compounds and clay particles carried down by percolating water.
|
subsoil
|
|
peeling off thin layers of soil from the land surface; accomplished primarily by wind and water.
|
Sheet erosion
|
|
the removing of thin layers of soil as little rivulets of running water gather and cut small channels in the soil.
|
rill erosion
|
|
removal of layers of soil, creating channels or ravines too large to be removed by normal tillage operations.
|
gully erosion
|
|
denuding and degrading a once fertile land, initiating a desert-producing cycle that feeds on itself and causes long-term changes in soil, climate, and biota of an area.
|
desertification
|
|
water saturation of soil that fills all air spaces and causes plant roots to die from lack of oxygen; a result of overirrigation.
|
waterlogging
|
|
a process in which mineral salts accumulate in the soil, killing plants; occurs when soils in dry climates are irrigates profusely.
|
salinization
|
|
dramatically increased agricultural production brought about by “miracle” strains of grain; usually requires high inputs of water, plant nutrients, and pesticides.
|
green revolution
|
|
organisms created by combining natural or synthetic genes using the techniques of molecular biology.
|
Genetically modified organisms (GMO's)
|
|
ecologically sound, economically viable, socially just agricultural system. Stewardship, soil conservation, and integrated pest management are essential for sustainability.
|
Sustainable Agriculture or Regenerative Farming
|
|
plowing along hill contours; reduces erosion
|
contour plowing
|
|
planting different kinds of crops in alternating strips along land contours; when one crop is harvested, the other crop remains to protect the soil and prevent water from running straight down a hill.
|
strip-farming
|
|
shaping the land to create level shelves of earth to hold water and soil; requires expensive machinery, but it enables farmers to farm very steep hillsides.
|
terracing
|
|
plants that grow for more than two years.
|
perennial species
|
|
plants, such as rye, alfalfa, or clover that can be planted immediately after harvest to hold and protect the soil
|
cover crops
|
|
plants grown under a canopy of taller trees, which provides habitat for birds and other wildlife.
|
shade-grown
|
|
farming methods that preserve soil and save energy and water through reduced cultivation; includes minimum till, conserve-till, and no-till systems.
|
Reduced tillage systems
|