Geog 101A Midterm

Front 1

ecological redundancy

Back 1

the given role of a species in an ecosystem can be played by more than one species

Front 2

name an example of an ecosystem with an inverted biomass pyramid

Back 2

grasslands

Front 3

assimilated food energy

Back 3

proportion of energy actually absorbed by an organism from its food source

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population

Back 4

a group of individuals of the same species

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community

Back 5

populations inhabiting a particular environment

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ecosystem

Back 6

a collection of communities interacting with the physical environment

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biomes

Back 7

ecosystems grouped together based on their primary vegetation and animal communities. 6 main classifications: marine, freshwater, forest, grassland, desert, and tundra.

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abiotic components

Back 8

nonliving parts of an ecosystem. ie; light, temperature, wind, water, and soil characterstics.

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soil

Back 9

a combination of inorganic materials (clay, sand, pebbles), and decaying organic matter.

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loams

Back 10

soils containing a mixture of clay and decomposed organic materials

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soil permeability

Back 11

the rate at which water can move through soil

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range of tolerance

Back 12

the range of conditions a species can tolerate and still survive

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niche

Back 13

a specific combination of physical, chemical, and biological conditions needed for a particular species growth

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competitive exclusion principle

Back 14

no two species can occupy the same niche in the same area

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specialist

Back 15

species with relatively narrow niches and are generally more susceptible to population fluctuations

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generalist

Back 16

species with broad niches, more successfully adapted to new environments

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intraspecific competition

Back 17

occurs among members of the same species

Front 18

interspecific competition

Back 18

occurs between different species

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resource partitioning

Back 19

resources are used at different times or in different ways by species with an overlap of fundamental niches

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territory

Back 20

a specific area dominated by a certain individuals

Front 21

parasitism

Back 21

the predator lives on or in the prey (host)

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mutualism

Back 22

the relationship benefits both species

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commensalism

Back 23

relationships that only benefit one species but do not harm the other

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keystone species

Back 24

species with a strong influence on the entire community

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extripation

Back 25

when a species is removed from its community as a result of human activity

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biodiversity

Back 26

the sum of all interactions between abiotic and biotic factors in an ecosystem

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ecological succession

Back 27

the gradual replacement of one assemblage of species by another as environmental conditions change over time

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primary succession

Back 28

the colonization of a previously unvegetated surface

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seed bank

Back 29

seeds that remain dormant until there is suitable conditions for growth

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seral stage

Back 30

growth stages of an ecosystem

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climax community

Back 31

a well defined, stable stage of vegetation in an ecosystem

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disturbances

Back 32

relatively discrete event in time and space that alters the structure and function of populations, communities, and ecosystems, ie; fires, insect infestations, flooding, storms

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cyclic succession

Back 33

a community progresses through several seral stages but is then returned to an earlier stage by natural phenomena

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ecotones

Back 34

the blending of seral stages, contain the highest species diversity

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climatic climax

Back 35

climax vegetation for a given area, controlled by climate

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edaphic climax

Back 36

climax vegetation for a given area as controlled by soil conditions

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secondary succession

Back 37

succession on previously vegetated surfaces, soil is already present

Front 38

intermediate disturbance hypothesis

Back 38

theory suggesting ecosystems subject to moderate disturbance generally maintain high levels of diversity compared to ecosystems that experience low levels or high levels of disturbance

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Gaia hypothesis

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theory that suggests the ecosphere itself is a self-regulating homeostatic system in which the biotic and abiotic components interact to produce a balanced, constant state

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inertia

Back 40

the ability of an ecosystem to withstand change

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resilience

Back 41

the ability of an ecosystem to recover to the original state following disturbance

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alleopathic

Back 42

can directly inhabit the growth of surrounding species through production of chemicals in the soil

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polar amplification

Back 43

a positive feedback loop that increasing temperatures also increase the area of snow-free land in the summer

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synergism

Back 44

when the effect of two or more separate entities together is greater than the sum of of the individual entities

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carrying capacity

Back 45

the number of individuals of a species that can be sustained in an area indefinitely

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biotic potential

Back 46

the capacity of a species to increase in number

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r-strategists

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species which produce large numbers of young early in life and over a short period of time but invest little parental energy in their upbringing

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k-strategists

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species which produce few offspring but devote considerable effort to ensuring that these offspring reach maturity

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evolution

Back 49

a change in the genetic makeup of a population with time

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speciation

Back 50

the process is which a population has undergone so much change that it is no longer able to interbreed with the original population and a new species is formed

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co-evolution

Back 51

changes in one species cause changes in another

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contemporary evolution

Back 52

evolution occurring at a more rapid pace due to the influence of human development

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extinction

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the elimination of a species that can no longer survive under new condition

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matter

Back 54

an item with mass that takes up space

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law of conservation of matter

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matter can neither be created nor destroyed, but merely transformed from one form into another

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nutrients

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naturally occurring elements that are necessary for sustaining life

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macronutrients

Back 57

needed in relatively large amounts by all organisms

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micronutrients

Back 58

needed in lesser amounts by most species

Front 59

biogeochemical cycles

Back 59

how nutrients are dispersed through various components of the ecosphere

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anadromous

Back 60

fish that part of their lives in salt water and part in fresh water

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guano

Back 61

phosphorus returned to the cycle through animal waste

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aerobic

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bacteria in the presence of oxygen

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anaerobic

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bacteria in the absence of oxygen

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nitrogen fixation

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the transformation of atmospheric nitrogen (N2) into usable nitrates or compounds to be filtered through the environment

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denitrification

Back 65

the transformation of nitrates into nitrogen gas to be returned to the atmosphere

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eutrophication

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a natural process of nutrient enrichment of water bodies that leads to greater productivity

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oligotrophic

Back 67

systems with relatively low nutrient levels

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eutrophic

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systems with relatively high nutrient levels

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mesotrophic

Back 69

systems between eutrophic and oligotrophic, average levels of nutrients

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non-point sources

Back 70

sources smaller, various of water contamination that need to be controlled at the source (agriculture/city runoff)

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point sources

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large, single discharge sources of water contamination such as sewage plants of industrial processes

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acid deposition

Back 72

the increase of acidity in the atmosphere due to human interference in the nitrogen and sulphur cycles

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indicators

Back 73

specific facets of a particular system, such as the population of a key species within an ecosystem, that tells us something about the current state of the ecosystem but do not help us understand why the system is in that state

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estuary

Back 74

coastal regions, such as inlets or mouths of rivers, where salt water and fresh water mix

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ecological sustainability

Back 75

the capacity of an ecosystem to maintain essential functions and processes, and retain biodiversity in full measure over the long term

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productivity

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the rate at which energy is transferred into biomass

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chemical energy

Back 77

stored in the bonds of molecules, has no mass and takes up no space

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calorie

Back 78

an amount of heat necessary to raise on gram or millimetre of water one degree celsius, starting at 15oC

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hyper abundance

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when a native species achieves an undesirable abundance