Test #2- Lehr

Evolution
consists of genetic changes in population of organisms across generations
Natural selection
process by which inherited characteristics that enhance survival and reproduction are passed on more frequently to future generations than those that do not
mutations
accidental alterations that arise during DNA replication
adaptive trait
a trait that promotes success
artificial selection
process of selection conducted under human direction
Biodiversity
refers to the sum total of all organisms in an area
Population
group of individuals of a particular species that live in a certain area
species
particular type of organism
Speciation
process by which species are generated
phylogenetic trees
treelike diagrams that represent life’s history
fossil
an impring in stone of a dead organism
fossil record
cumalitive body of fossils worldwide
mass extinction events
five events that killed off massive numbers of species at a time
Ecology
study of interactions among organisms and between organisms and their environment
resource partitioning
the species partition, or divide, the resource they use in common by specializing in different ways
Predation
the process by which individuals of one species hunt, capture, kill, and consume individualsof another species
Parasitism
relationship in which organism depends on another for nourishment or some other benefit while simultaneously doing the host harm
herbivory
common expoitative interactions which occurs when animals feed on the tissues of plants
Symbiosis
mutualistic relationship that occurs in close physical contact
mutualism
relationship in which interacting species benefit from one another
Community
an assemblage of species living in the same place at the same time.
trophic level
rank in the feeding hierarchy
Keystone species
A species that has strong or wide-reaching impact far out of proportion to its abundance
Succession
a predictable series of changes that communities undergo when affected by a disturbance
Primary succession
follow a disturbance so severe that no vegetation or soil life remains from the community that occupied the site. A biotic community is built from scratch
Secondary succession
begins when a disturbance dramatically alters an exisitng community but does not destroy all life or organic matter
pioneer species
Species that arrive first and colonize the new substrate
invasive species
non-native organism that can alter a community and is one of the central ecological forces in today’s world
Ecological restoration
restoring an environment to its original state
Biome
a major regional complex of similar communites
Temperate deciduous forest
characterized by broad-leafed trees that are deciduous (lose their leaves in winter)
Temperate grasslands
arise when temperature differences between winter and summer become more extreme and rainfall diminishes
temperate rainforest
heavy rainfall; tall trees grow and forest interior is shaded and damp
Tropical rainforest
characterized by year-round rain and uniformly warm temperatures
tropical dry forest
warm year round, but rainfall is lower overall and highly seasonal
savanna
drier tropical region; precipitation arrives in distinct rainy seasons
desert
waterfall is very sparse; hot
Tundra
Dry; cold; little daylight
Boreal forest
cooler, drier regions; breif intenstly productive summers
chaparral
evergreen shrubs; highly seasonal (mild wet winters, warm wet summers)
IPAT model
Impact on environment = population x affluence x technology
Demography
social science that applies the principles of population ecology to the study of statistical change in human populations
demographical transition
model of economic and cultural change
agriculture
practice of raising crops and livestock for human consumption
traditional agriculture
relies on human and animal muscle power along with hand tools and simple machine
industrialized agriculture
uses large scale mechanization and fossil fuel combustion; irrigation and synthetic fertilizers are also used
soil
plant supporting system consisting of disintegrated rock, organic matter, water, gases, nutrients, and microorganisms
Parent material
base geological material in a particular location
Bedrock
the continous mass of solid rock that makes up Earth’s crust
weathering
the physical, chemical, and biological processes that turn large rock particles into smaller particles
horizon
layer of soil
soil profile
cross-section as a whole of soil
leaching
the process whereby solid particles suspended or dissolved in liquid are transported to another location.
topsoil
consists mostly of inorganic mineral components such as weathered substrate, with organic matter and humus from above mixed in
desertification
a loss of more than 10% productivity due to erosion, soil compaction, forest removal, overgrazing, drought, salinization, climate change, depletion of water sources.
Dust Bowl
The event in which millions of tons of top soil in the Great Plains blew away.
crop rotation
farmers alternate the type of crop grown in a given filed from one season to the next
Contour farming
consists of plowing furrows sideways across a hillside, perpendicular to its slop and following the natural contours of the land
Terracing
farmers cut level platforms into steep hillsides to contain water from irrigation and precipitation
intercropping
planting different types of crops in alternating bands or other spatially mixed arrangments
Shelterbelts
rows of trees or other tall, perennial plants that are planted along the edges of fields to slow wind
irrigation
artificial provision of water to support agriculture
waterlogging
occures when roots are saturated, and deprived of gases and suffocated
salinzation
the buildup of surface salts in surface layers
fertilizer
any of various substances that contain essential nutrients
Inorganic fertilizers
mined or synthetically manufactured mineral supplements
Organic fertilizers
consist of the remains or wastes of organisms and include animal manure, crop residues, fresh vegetation, and compost
overgrazing
when too many animals eat too much of the plant cover, impeding plant regrowth and preventing replacement
food security
guarantee of an adequate and reliable food supply available to all people at all times
monoculture
uniform planting of a single crop
green revolution
a movement of using mechanization and efficient crops to increase crop outputs
pesticides
poisons that target pest organisms
biological control
battling pests with organisms that eat of infect them
integrated pest management
numerous techniques are integrated, including biocontrol, use of chemicals, close monitoring of populations, habitat alteration, crop rotation, transgenic crops, alternative tillage methods, mechanical pest removal
pollination
process by which male sex cells of a plant fertilize female sex cells of a plant
Genetic engineering
any process whereby scientists directly manipulate an organism’s genetic material in the laboratory by changing the DNA
GMO
organisms that have been genetically engineered using recombinant DNA
biotechnology
material application of biological science to create products derived for organisms
precautionary principle
one should not undertake a new action until the ramifications are well understood
aquaculture
raising fish and shellfish in controlled environments
sustainable agriculture
farming and ranching that does not deplete soils faster than they form and maintains clean water
organic agriculture
use no synthetic fertilizers, insecticides, fungicides, or herbicides