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Convergent plate boundary
A region where plates are pushing together and where a mountain range, island arc, and/or trench will eventually form; often a site of much seismic and volcanic activity.
The solid, outer layer of the earth that consists of the crust and the rigid upper part of the mantle
positive feedback loop
Situation in which a change in a certain direction provides information that causes a system to change further in the same direction. For example erosion and population growth.
Occurs when an output of matter, energy, or information is fed back into the system as an input and leads to changes in that system.
negative feedback loop
Situation in which a change in a certain direction provides information that causes a system to change less in that direction.
New properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases.
The buildup over time of nutrients in freshwater lakes and ponds that leads to an increase in the growth of algae, usually due to an excess of nitrogen or phosphate.
The watery areas of the earth, including oceans, lakes, rivers, and other bodies of water
British ecologist who counted the term "ecosystem", particular portion of the world which forms a home for the organisms which inhabit it
Net Primary Production
The gross primary production of an ecosystem minus the energy used by the producers for respiration
The amount of chemical energy in consumers' food that is converted to their own new biomass during a given time period
net primary productivity
The gross primary productivity minus the energy used by the producers for cellular respiration; represents the storage of chemical energy in an ecosystem available to consumers.
The application of ecological principles to the study of land-use patterns; the scientific study of the biodiversity of interacting ecosystems
An area of habitat that differs from its surroundings and has sufficient resources to allow a population to persist
The transition from one type of habitat or ecosystem to another, such as the transition from a forest to a grassland.
A collection of populations that have regular or intermittent gene flow between geographically separate units.
Geographic Information Systems, collection and display of data in an interactive and collaborative way to help organize for scientists to analyze and notice trends.
The process in an ecosystem in which producers take in carbon dioxide from the atmosphere during photosynthesis and consumers, having eaten producers, release carbon into the atmosphere as carbon dioxide
The movement of phosphorus from the nonliving environment into living things and then back into the nonliving environment
The transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere
The assimilation of atmospheric nitrogen by soil bacteria and its release for plant use on the death of the bacteria
nitrogen fixing bacteria
Bacteria that convert nitrogen in the air into forms that can be used by plants and animals.
The oxidation of ammonium compounds in dead organic material into nitrates and nitrites by soil bacteria (making nitrogen available to plants)
A process to synthesize ammonia on an industrial scale. The process has enabled humans to double the natural rate of nitrogen fixation on Earth and thereby increase agricultural productivity, but also altered the nitrogen cycle.
German Chemist. He won the 1918 Nobel Prize in chemistry for the development of the process used for synthesizing ammonia from its elements.
Bacteria which often live in damp soil, and which convert nitrates into nitrogen gas
The paths water take through its various states-vapor, liquid, solid- as it moves throughout the oceans, atmosphere, groundwater, streams, etc...
Subterranean, porous, water-holding rocks that provide millions of wells with steady flows of water.
The upper surface of underground water in an aquifer; the upper boundary of the zone of saturation
The part of the subsurface water that is in the zone of saturation, including underground streams.
A type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together
A type of ingneous rock that generally contains large crystals and forms when magma cools slowly beneath Earth's surface. Best example is Granite
Fine-grained igneous rock that forms when magma cools quickly at or near Earth's surface. Best example is Basalt.
A type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions
The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle
Divergent plate boundaries
Situation with tectonic plates spreading apart, new crust being formed (ex. mid-ocean ridges, rift valleys).
transform plate boundary
Places where crustal plates shear laterally past one another. Crust is neither produced nor destroyed at this type of junction.
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