grasslands Flashcards
(135 cards)
1
Q
what forms grasslands
A
too much rain for true desert but not enough for a forest
2
Q
generalizations about grassland plant species
A
grasses of multiple species and genera but mostly dominated by a few species
most with rhizomes (underground spreading stems that send up shoots and nodes and store starches up to 1/2 of biomass); wind pollination; perennial bunchgrasses
will grow back after fire, grazing, wind, extreme temp
3
Q
temperatures in grasslands
A
huge range from seasons often deep into the negs in winter (more to north), over 100 in summers
4
Q
grassland precipitation
A
6-40in (15-100cm)
5
Q
grassland precipitation season
A
scattered thunderstorms in summer but most rain/snow in winter and cooler times
6
Q
grassland soils
A
mollisols (basic, hummus rich, dark, productive, Ca/Mg)
mollisols are most common soil type in US (21.5%) and 7% of ice free land worldwide
found in W great plains and scattered rest of west
7
Q
grassland growing season
A
typically 120-200 days
8
Q
mollic epipedon
A
dark, fertile region of topsoil
9
Q
grasslands topography
A
flat, some rolling hills, steep canyons
10
Q
grasslands fire
A
frequent due to summer thunderstorms
necessary to maintain ecosystem and keep back trees and shrubs, grasses have survival mechs
11
Q
grasslands fauna
A
grazing animals like deer, elk, bison in large herds
songbirds and small burrowing mammals very common
12
Q
tallgrass prairie
A
usually around 1-3m (3-9ft), deep roots, nearest eastern deciduous forests
precip around 25-40in (65-100cm), usually around 34in
13
Q
Tallgrass prairie problems
A
most plowed and planted w/ wheat/corn; increased drainage and runoff reduces moister areas
14
Q
Tallgrass prairie plants
A
Big bluestem, sand bluestem, indian grass, slough grass, switchgrass
15
Q
mixed grass prairie
A
usually under 4ft (1.3m) in height; usually around 3ft
precip around 14-25in (35-65cm)
mixed with taller grasses growing in slightly wetter areas and shorter ones in drier areas
16
Q
mixed grass prairie species
A
little bluestem grass, june grass, needle grass, dropseed grass, wheatgrass, wild rye
17
Q
mixed grass prairie problems
A
almost entirely planted over with crops such as corn and soybean
18
Q
shortgrass prairie
A
nearest to western deserts, cover most area of the 3 groups in N america; mostly W of latitude 100W
most less than 20in (50cm), usually below 1ft; fewer forbs because lower rain favor grasses; can’t grow bigger bc no water
precip usually around 14-10in (25-35cm)
also called ‘the plains’
19
Q
shortgrass prairie problems
A
some takeover for irrigated corn and crops; mostly just overgrazed for cattle, fenced from native grazers, invasives on ranges
20
Q
shortgrass prairies species
A
buffalo grass, galleta grass, needle grass, grama grass, penn sedge
21
Q
bunchgrass prairie
A
also called palouse prairie (near palouse river in WA)
found in plains N of great basin, colorado, UT, CA, WY, MT
22
Q
bunchgrass prairie species
A
purple needlegrass, sagebrush, bluebunch wheatgrass
23
Q
bunchgrass vs. typical plains grass
A
typical plains grass
bunchgrass sends up new shoots from its base forming a clump
Most prairie grasses have mat-like roots that spread and produce new shoots spread out from one another
24
Q
characteristics of grassland grazers
A
wide set eyes, large herds, camoflage and speed, good vision,
25
characteristics of grassland birds
lots of them (lots of songbirds)
strong fliers due to high winds, nest in tall grasses,
26
characteristics of small grassland mammals
many in colonies, many burrow, many hop for visibility
27
grassland history
during pleistocene/miocene (50-3.5MYA) mountains in N amer make grassland climate more favorable
after pleistocene ice ages, drier/warmer climate expand grasslands
28
savanna
tropical grassland with few uniformly dispersed trees that aren't dense enough to form a closed canopy
29
savanna reqs
20-50in of rain concentrated in 6-8 months followed by long hot drought where fires are common; average daily temp never drop below 64F
30
types of savanna
climactic savannas - classic all rain in one season and fire and drought maintain in rest of year
edaphic savannas - thin or clay soils that inhibit tropical forest growth
derrived savannas - human or elephant deforestation creates critical mass of grass to burn away tree sprouts
31
savanna plants
generally has a dominant grass or few grass/forb species and scattered deciduous trees
grasses: includes elephant grass which is like 10ft
trees: acacia, baobab, candelabra
32
savanna seasons
winter is dry starting October with strong winds, little rains, few lightning
summer is wet
33
savanna fires
during winter dry season
small animals in burrow, insects die, grasses burn but roots ok
34
savanna problems
desertification, clearing for farming, poaching, overgrazing
35
grassland problems
clearance for farming/grazing, species disruption (poaching and overhunting/invasives), hunting
36
savanna locations
brazillian horn highlands, venezualan campos, sahel (lot thicker than shown), E africa and S africa, parts of india and SE asia; N australia
37
Derived savanna
much of the world's savanna is actually tropical forests that were cleared by people and then animals and fire maintained the grasses
38
veldts
grasslands of South Africa
39
puszta
grasslands of Hungary
40
temperate grasslands definition
clearly defined hot summer and cold Winters
41
temperate grasslands distribution
plains of US, pampas in Argentina, eurasian steppes from ukraine through balkash, mongolia and manchuria area, turkey
42
rainfall in temperate grasslands
moderate: 20-35in per year (more rain is taller grass)
mostly late spring early Summer
43
Entisols
soils that show little or no evidence of pedogenic horizon development
44
temperate grasslands soil
mollisols dark and Rich
45
savanna soils
rich but often leached
46
temperate grasslands fire
there is some fire in the drought season in fall or summer, but not as much or as important as savannas
47
temperate grasslands seasons
very hot summer and cold winter
rains in late spring and early Summer and drought for the rest of the year
48
trees in temperate grasslands
some riparian but basically nonexistent in actual grass unlike savanna
49
Riparian
on a river bed
50
temperate grasslands Max and min temperatures
temperate grasslands Max and min temperatures
max over 100f min like -40
51
temperate grasslands problems
destruction for farming and grazing
52
steppe rain
10-20in in winter (30-50cm)
53
steppe
refers to european grasslands; treeless entirely; dry (30-50cm); drought common, feather grasses dominant (feathery flowers, mostly stipa); cold winter, moderate summers where they get most of rain; grasses die back in august and don't revive until spring
54
steppe problems
wheat and grazing destroying it, salinization from irrigation
55
largest intact savanna
N australia
56
list savanna types
tropical, temperate, mediterranean, montane, flooded
57
tropical savanna
synonymous with typical savanna
58
temperate savanna
sketchy term to describe any temperate grassland with sparse trees and shrubs
59
mediterranean savanna
savannas in mediterranean climates with interspersed trees (med, socal)
ie: oak savannas
60
flooded savannas
usually tropical savannas that are flooded part of the year like the pantanel or the okavango
61
alpine savanna
or montane savanna; found above the tree line high up in equitorial areas, elsewhere is just alpine grassland; same as alpine tundra?
62
alpine grassland
found above the treeline or polar direction from treeline but not in permafrost
mostly tussock fescue grasses where temperature never tops 50F in summer
drops 6.5C for every thousand feet up of 3 degrees?
63
successional grasslands
grasslands maintained by fire and grazing and disturbances that would otherwise be taken over by trees and shrubs
64
temperate vs. savanna
mostly by distance from equator (savanna usually between tropic of capricorn and cancer)
savannas have trees and shrubs while temperate typically little to none
climate: rains and temps
65
savanna woodland
tree canopy covers >50% of area
66
savanna parkland
20-50% of area is covered by tree/shrub canopy
67
savanna grassland
<20% of the area is covered by trees/shrubs
68
prairie
name given to US grasslands
69
california grasslands
used to be sagebrush steppes in owens valley and NE and stipa pulchra (purple needlegrass) bunchgrasslands through central and Socal
bunchgrasses disappeared
70
steppe climate
dry (30-50cm); drought common summer-autumn; precipitation distributed with rain in summer and some snow in winter but dries out fast in summer rains
cold winters below freezing for 5 months; moderate summers up to around 70's (F)
71
steppe plants
dominated by feather grasses (stipa sp); fescue (festuca), oats (avena), sedges (carex), bluegrass (poa bulbosa), tulips (tulipia), sagebrushes (artemisia)
72
forest steppe
where the steppe meets the northern boreal forests in a transition zone where trees more and more dense as north; N of meadow steppe
73
meadow steppe
moister climate; more sedges and feathergrasses (needlegrasses/stipa), often used for livestock
south of forest steppe, north of dry steppe
74
Dry steppe
ground is dry most of the time because rainfall less than amount that can evaporate; mostly shorter feathergrasses/needlegrasses and fescues
merges with desert to south and meadow steppe to north
75
types of steppe
forest steppe: as steppe merges with taiga to north
meadow steppe: wetter steppe S of forest steppe
Dry steppe: drier steppe merging into deserts
76
pampas
south american grasslands in rio de la plata region, Uru and Arg mostly
77
pampas climate
warm summer about 30C and cool winter around 15C; rain varies from 20-40in
78
sterile pampa
dry plain that can give way to deserts; found to western portion up towards andes; salty soil; dominant plants are thornbrushes (ie: chanal); rain around 20in
79
eastern pampas
wetter side closer to sea around 30-40in precip; very productive ag land; dominated by pampas grass (same one invasive in CA), few forbs inbetween but pretty dominant; high fire frequency kills most trees except ombu
80
veld
extends high into mountains; mostly in E S africa and lesotho; rain 20-40in
81
types of veld
high veld towards central in high elevation areas
bushveld is dry savanna-like
cape middle veld is to west of high veld in the middle of S africa
sweet veldt is areas with <25in rain where grasses retain nutrients through winter
sour veld is wetter areas where pull in water during winter dry season
82
veld plants
dominated by red oat grass; bermuda grass, others; mostly taken over by crops like corn now
83
south american savannas
llanos: grasslands around venezuela, dominated by trachypogon; dry winter, rain in summer-fall (40-80in); temp around 80F tiny variation between seasons;
cerrado: around horn of brazil (huge); campo limpo is no tree, campo sujo is few tree; diverse, mostly trachypogon tussock grasses; 70-80F w/ little seasonal variation; 40-70in in summer, winter drough 1/2yr; includes pantanal (largest wetlands)
84
australian grassland types
mitchell grass: N edge of desert center; 15-30in, summer 100+, frosts, acacia; dominated by mitchell grass, bluestem, brigalow
mulga scrub: E-W edges of desert; dominated by mulga (type of acacia) and spinifex grass
saltbrush savanna: atriplex saltbrush; porcupine grass in dune areas stabilize
in general, they're all savanna or desert
85
origin of grasses
55-70mya, not significant until 20-30mya; first around tropics
86
complete soil profile
O1 - organic litter
O2 - partially decomposed organic material
A1-mineral w/ fine bits of organic matter
A2-mineral material with nutrients leached from above
A3/B1-transitional layer
B2-nutrient accumulation
B3-transitional layer
C-parent material
R-bedrock
87
laterite
rock-soil clumps that are clay-like and have iron and aluminum oxides; tropical soil type
88
grasslands storms
strong and often short, water evaporates
89
gullies
large canyons from rills; form in grasslands bc grass usually break force of rain but when gone, erosion rapid into rills then gullies
90
how many grass species
9k in poaceae
91
origin of grass
first 60mya, all continents but rare by 45mya (mostly forest edge, tropical)
15mya: first grasslands appear S amer then E afr; wind patterns shift making dry seasons in continental interior; 2.5mya great plains
92
Match the type of ecosystem service to the example of an ecosystem service
Provisioning = Food security
Regulating = Climate stability
Supporting = Productive soil
Cultural = Inspirational landscape
93
The spirit of Aldo Leopold's Land Ethic
Caring for the land is caring for ourselves
94
C3 photosynthesis
cool season plants use this and work best at 50-70 degrees f
95
C4 photosynthesis
warm season plants use this and work best at 70-90 degrees f
96
Meristematic tissue at base of plant
allows plants to regrow rapidly after defoliation
97
Silica bodies in cell wall
Allows plants to tolerate herbivory
98
sod-forming grass
tillering primarily from belowground rhizomes and aboveground stolons
99
Annual grass
populations maintained mainly via sexual reproduction from seed each year
100
Perennial grass
populations maintained mainly via asexual clonal growth of tillers
101
The basic unit of a grass plant is the
phytomer
102
phytomers are comprised of a
blade, collar, and sheath
103
phytomers are comprised of a blade, collar, and sheath attached to the stem at nodes where _________ meristematic tissue allows stem elongation to occur
intercalary
104
Wildlife in Grasslands
Includes eagles, coyotes, bison, and prairie chickens.
105
Plant Life in Grasslands
Includes buffalo grass, sunflowers, and clover.
106
Savanna Dry Season
Period with minimal rainfall, peaks in January.
107
Savanna Wet Season
Crucial for regrowth, occurs before dry season.
108
Savanna area
Covers 5 million square miles globally.
109
Savanna Summer Temperature
Ranges from 78° to 86° F (25° - 30° C).
110
Savanna Winter Temperature
Typically 68° to 78° F (20° - 25° C).
111
Savanna Average Rainfall
76.2-101.6 cm (30-40 inches) annually.
112
Savanna Soil Composition
Porous soil with rapid drainage and low humus.
113
Savanna Soil pH
Usually between 4.8 to 6.3; acidic.
114
Savanna Fauna
Includes giraffes, zebras, lions, and elephants.
115
Savanna Flora
Dominated by grasses and acacia trees.
116
Savanna Size
Approximately 20% of Earth's surface.
117
Animal Adaptations
Includes camouflage, hibernation, and migration.
118
Plant Adaptations
Deep roots, thin leaves, and water storage.
119
Threats to Savanna
Includes poaching, overgrazing, and land clearing.
120
Edaphic Savanna
Savanna influenced by soil conditions, not fire.
121
Prairie Conditions
Grassland ecosystem, often fertile and flat.
122
Steppe
Dry grassland with hot summers and cold winters.
123
Average Steppe Rainfall
Receives 25.4-50.8 cm (10-20 inches) annually.
124
Steppe Temperatures
Summer can reach 45 °C (115 °F); winter -55 °C (-65 °F).
125
Steppe Soil Composition
Deep, dark, nutrient-rich soil from grass roots.
126
Steppe Animal Adaptations
Rodents store dry plant parts for winter.
127
Steppe Plant Adaptations
Plants withstand drought and grazing conditions.
128
Genetic Diversity
Variety of genes within a species population.
129
Species Diversity
Number and abundance of species in an area.
130
Dust Storms
Caused by loose soil during droughts post-plowing.
131
Prairie Regions
Most converted to farms or grazing land.
132
Prairie Plant Species
Includes asters, sunflowers, and wild indigos.
133
Microclimate
Hundreds of flower species grow among grasses.
134
Cottonwoods
Trees found in river valleys of grasslands.
135
Exclave
Pannonian steppe located mostly in Hungary.
