ecology pt 2 Flashcards
(93 cards)
1
Q
succession
A
gradual and directional change in community structure through time
2
Q
describe
early successional species ( pioneer species)
A
high growth rates, small size, high degree of dispersal: r-strategists
3
Q
late succesional species
A
lower rates of dispersal and colonization, slower per capita growth rate, larger, K- strategists
4
Q
primary succession
A
occurs on a site previously unoccupied by a community
5
Q
secondary succession
A
occurs on a previously occupied sites but after a disturbance
6
Q
where does primary succession occur?
A
sites that have never supported a community
rocks, outcrops, cliffs, sand dunes
7
Q
what are the most successful pioneering plants?
A
grasses
8
Q
climax community
A
assemblage of characteristic plants that define an ecosystem
9
Q
intermediate disturbance hypothesis
A
species diversity is at its best when disturbance isn’t too constant or too rare
10
Q
organismic concept of communities
A
- transitions between communities are narrow
- communities have few species in common
- common evolutionary history and simialr fundamental responses and tolerances
11
Q
individualistic/continuum concept of community
A
- species associate bc of similairties in the tolerance
- species do not cluster along enviornmental gradients
- trasitions are gradual and difficult to identify
12
Q
landscape
A
an area that is heterogenous in at least one factor of interest
13
Q
habitat patches
A
relatively homogenous community types that differ from their surroundings in physical structure
14
Q
fragmentation
A
when large patches of habitat are reudced to small isolated patches
15
Q
what results in habitat fragmentation
A
human activity (amongst other things but mainly humans)
16
Q
mosaic
A
landscape with different kinds of patches
17
Q
edges
A
perimeters of each patch
dynamic and may change through time
18
Q
types of patches
A
- narrow and abrupt
- wide with tranistion zone/ecotone
- straight
- concoluted
- perforated
19
Q
the edge effect
A
phenomenon where edge communites are often diverse
19
Q
what are some possible problems with the edge effect?
A
- attraction of more predators (ecological trap)
- restricts dispersal
20
Q
corridor
A
particular strips of landscape differing from adjacent land on both sides
- incr. gene flow, promote reestablishment of locally extinct populations, incr. species diversity
- may provide habitats
21
Q
ecotone
A
transitional zone between two communities
ex: fencerows, forest to marshlands transitions, land-water interfaces,
22
Q
characteristics of ecotones
A
vegtational sharpness, physiognomic change, occurrence of a spatial community mosaic, many exotics species, species richness higher or lower on either side of the ecotone
23
Q
matrix
A
“background ecological system” of a landscape
24
connectvity
measure of how connected or spatially continuous a corridor, network, or matrix is
25
what is dispersal important for
- gene flow
- recolonialization of extinct habitat patches
- shifting ranges in response to climate change
26
what is dispersal between habitat patches affected by
- plants: seed size and dispersal vector (wind, animal, humans)
- animals: dispersal behavior( vagility) and resitance of matrix
27
theory of island biogeography
number of species on an island represents a dynamic equilibrium between the immigration of new species and extinction of established ones
28
what are the inputs and outputs of photosynthesis
Carbon dioxide, light energy and water -> oxygen and glucose
29
inputs and outputs of respiration
glucose + oxygen -> carbon dioxide + energy
30
gross primary productivity (GPP)
total rate of photosynthesis or the energy assimilated by autotrophs
31
net primary productivity (NPP)
rate of energy storage as organic matter after respiration
32
net primary productivity equation
NPP = GPP -R
| net primary productity = gross primary producivty - respiration
33
standing crop biomass
amount of organic matter present at any given time
## Footnote
= mass of organic matter/area= g/m^2
34
transpiration
- 90% of plant water use
- allows plants to transport water and mineral nutrients from the soil to growth regions
- exhalation of water vapor
35
evapotranspiration
loss of water from the soil both by evaporation and transpiration from the leaves
36
factors that influence productivity
- disturbances (herbivory fire)
- seasonal variations ( cold winter= lower productvity)
- nitrogen availability incr. productivty
37
bioaccumulation
with each trophic level, molecules increase in concentration
## Footnote
DDT
38
secondary productivity
energy put towards growth and reproduction
39
how much energy is tranfered in a trophic level
10%
40
decomposition
breakdown of chemical bonds of organic molecules
41
nutrient cycle
movement and exchange of organic and inorganic matter into the production of living matter
42
decomposers
organisms that feed on dead organic matter or detritus
43
detrius
non-living matter (feces + dead woods, animal tissue etc)
44
mineralization
transformation of nutrients contained in organic compounds into inorganic forms
45
net mineralization rate
difference between the rates of mineralization and what is used by the decomposers
46
retranslocation/resorption
process of recyling nutrients within the plant
47
main reservoir of hydrologic cycle
oceans (97%)
48
aquifers
underground reserviors of water
49
effects of human activities on the water cycle
- withdrawing large amounts of freshwater
- polluting
- contributing to climate change
50
where is majority of freshwater
glaciers
51
what percentage of water is freshwater
2.5%
52
where is most carbon on earth
buried in sedimentary rock, not actively involved
53
where is the greatest accumulation of organic matter?
where decomposition is inhibited, frozen or waterlogged soils
54
site of main exchange of carbon dioxide
surface water
55
greenhouse gases
absorb thermal radiation- warms the earth's surface and lower atmosphere
56
FACE Experiment
long term experiment at Duke Experimental forest examining the effect of elevanted CO2
57
what forms is nitrogen available to plants
ammonium nh4+ and nitrate no3
58
Haber-Bosch process
making synthetic ammonia from nitrogen gas and hydrogen, led to the green rev.
59
what can excess nitrogen run off do
eutrophication
60
eutrophication
stimulates algae blooms that deplete the water of oxygen
61
how is atmospheric nitrogen fixated
symbiotic bacteria living with plants, cynobacteria
free living bacteria
62
what is the largest species
Coleopterea (beetles)
63
latitudinal gradient
increase in biodiversity from the poles to the tropics
## Footnote
largest factor is the greatest mean temp. at the equator compared to the poles
64
biodiversity hotspots
region with a high level of endemic species that has experienced greaat habitat loss
65
pleistoncene extinctions
11,000+ years ago many mammals went extinct in North america
## Footnote
human hunting caused/contributed to the extinction of many of the plesitocence large mammal
66
hypotheses for species diversity & latitude
1. spatial heterogeneity of the enviornment
2. climate stability
3. ecosystem productivity
67
spatial heterogeneity of the enviornment
habitats with complex physical structures have more niches than habitats with simple physical structures
68
# hypotheses for species diversity
climate stability
seasonal stability- a constant enviornment can allow species to specialize
historical stability- tropical regions have not been glaciated and have had more time for speciation to occur
69
# hypotheses for species diversity and latitude
ecosystem productivity
greater productivity= greater diversity
70
local (alpha) diverisity
species diversity of individual communities
71
regional (gamma) diversity
total species diversity across all communities within a geographic area
72
beta diversity
change in species diversity from one location to another
73
causes of extinction
overkill, over harvesting
habitat loss
invasive species
climate change
74
what happened to the passenger pigeon
exinct in 1914, from over hunting
75
what is the overall greatest threat to biodiversity
deforestation
76
example of introduced species turned invasive
zebra mussels- cover solld substrates and water intake pipes
asian carp were introduced by catfish farmers to remove alage
77
what is the first species to be place on the endangered species list due to climate change
polar bear
78
ecosystem services
services/goods that the enviornment provides to people
79
kinds of ecosystem services
provisioning
regulating
cultural
supporting
80
what did the brown tree snake do
eliminated a majority of native bird, lizard and bat species in guam
81
white-nose syndrome
fungal pathogen that infects cave hibernating bats and threatens extinction
82
CITES
treaty to protect endangered plants and animals
83
endangered species act of 1973
provides a program for the conservation of threatened and endangered plants and animals and the habitats
## Footnote
cannot take listed animals
84
population viabillity analysis (PVA)
species specific method of risk assessment frequency in conservation bio- determines the probabillity that a population will go extinct within a certain amount of years
85
reintroduction
deliberate release of a species into the wild from captivity where the animal surrvives
86
translocation
movement of wild caught animals from one natural location to anotther
87
peregrine falcon
removed from endangered species list after a 30 year recovery program
88
Aldo Leopold
considered the father of restoration ecology
89
restoration
improves community composition and ecosystem functions to return to a site to as close a natural system as possible
90
reclamation
inital goal is detoxification and terrain stabilization
91
replacement
create a new community entirely different from the orginal, often to replace habitat destroyed nearby
92
Bubbly Creek
reclamation- garbage pit for waste
