Quiz 3 Flashcards
What are two threats to Biodiversity?
Habitat Loss and Invasive Species
Habitat Loss
Deconstruction of habitat due to land conservation from agriculture, development, and deforestation
NUMBER ONE THREAT TO BIODIVERSITY
*Iowa Prairies lost 97% to corn and soy beans
Percentages of habitat loss
32% loss- Temperature Deciduous Dorest
44% loss- Tropical Rain Forest
66% loss- Marine Environments
97% loss- Tallgrass Praire
Invasive Species
Outcompete native species because no predators, diseases, or parasites to keep population under control
*Garlic Mustard and European Buckthorn
Types of ecosystem services
Provisioning, Regulating, Supporting, and Cultural services
pleaseriseslowlycourt
What are ecosystem services?
positive benefits provided by biodiversity that supports humans and other life!
-FREE FOR US
*Food
ex:
-Epibetadine- strong pain killer from poison frog
-Caddisfly silk- superglue for wet tissues in surgery
Provisioning Services
Biodiversity providing materials needed for survival and development of human societies
Regulating Services
Functioning ecosystems needed to support life
-providing clean water, purifying air, forming soils
*contains Resistance and Resilience
Resistance
ability of ecosystems to RESIST change
-increased species richness increases the resistance of the habitat
Resilience
the ability of ecosystems to RECOVER from change
-increase in species richness increases resilience
Supporting Services
support other categories
-1/3 bites of food you eat require POLLINATION
-need BEES, moths, butterflies, beetles
Cultural Services
How we integrate nature into our lives
-ecotourism
Ecotourism
travel for educational purposes
-aesthetics
-recreation
-education
Values of Biodiversity
1) ecosystem services
Stand
informal term used when describing an area of forest
Plot
the sampling unit used in estimating abundance (usually a circle or rectangle of 100-200 m2 for sampling trees)
Density
number of individuals/ area (units used are # trees/ ha)
dbh
diameter at breast height, a standard measure of tree size (measured in cm)
Relative Density
density for a species/ total density for all species (no units; this is a proportion)
Basal Area
cross sectional area of stump at dbh (units are m2)
Dominance
basal area of all trees in a given area (units are m2/ ha)
Relative Dominance
dominance of a species/ dominance of all species (no units)
Praires
grasslands without trees, where fire would frequently burn
-rare now in NE IOWA
savannas
grasslands with scattered fire-tolerant bur oaks, quite common in this area
*dissapeared from NE IOWA
Woodlands
open forests, look up and there are gaps in canopy to allow sunlight to reach the forest floor
*have noe become filled to be forests in NE IOWA
Forests
have highest density of trees, few gaps as you look up from forest floor
*changed in species that grow there now in NE IOWA
Species composition, density, and age structure of deciduous forests in NE IOWA vary because….
different tree species respond to differences in
-temperature
-moisture
-light availability
-fire history
Steep North facing slopes have…
sure
mama
bake
raisin
orcas
-sugar maple, basswood, red oak
-mesic forests with high diversity of shrubs and rich display of wildflowers
-plant species have adapted to cool, moist, shady conditions and don’t tolerate fire
ex: Twin Springs. Phelps Park
South or West facing slopes have…
-oak and hickory
-Drier and warmer climate on flatter parts of the landscape
-fire has played more of a role
example: Parts of Hickory Ridge Woods (HRW)
What is under the canopy of mature trees at HRW?
a sub canopy of saplings (young trees) and ironwood, a species that never gets tall enough to reach the canopy
What is the shrub layer?
spare, characterized by pickle species (gooseberry and prickly ash) and several invasive species (European buckthorn and Japanese barberry)
What is the herbaceous layer?
most interesting in spring when dozens of plant species are in bloom, including woodland phlox, wood anemone, and showy orchis
Environmental factors that affect woody species
-amount of sunlight (imp)
-nutrient and moisture availability in soil
-disturbance (type and frequency)
-herbivory
-disease
*plant species differ on how well they grow under different environmental conditions, resulting in interesting patterns in species disturbances
Common tree species in HRW can be ranked by their….
shade tolerance and (fire tolerance) is important to note to when a tree is first growing or at the establishment stage
two natural disturbance agents in the region are…
wind and fire
fire breaks
in hilly areas, steep slopes and river valleys stop spread of fire
What is the most fire resistant tree?
bur oak (older than 15 years with thick bark)
What do severe windstorms create?
knock down trees and create gaps in the canopy
wolf trees
oak trees with low spreading branches that are signs of open savanna or woodland environment
-grew up when there were few other trees around them so spread arches to capture the abundant sunlight available
Overarching theme of climate and biomes
the distribution of organisms is dependent on both biotic and abiotic factors such as climate
weather
the specific, short term atmospheric conditions like temp, precipitation, sunlight, wind, humidity
climate
the prevailing long-term weather conditions in an area
-30 yr avg of weather conditions
What affects climate?
-solar radiation
-global circulation patterns
-water bodies
-topography
solar radiation
light from the sun warms the earth (ground) and then warms the air above the ground
air (atmosphere)
a mix of 02,N2, CO2, and other gases
-holds moisture (water vapor- H20)
-the water vapor is responsible for trapping heat
intensity
varies on the planet depending on location
-most intense at the equator
-the angle of sunlight changes the intensity
Hot air
rises
-less dense
-absorbs and holds more water vapor
cool air
sinks
-more dense and holds less water
-if air has moisture in it when it cools it drops it’s water
Relative Humidity
how full is the air with water vapor at a certain temp
What causes rain
hot air at the equator, rises, cools, condenses, and then drops water vapor
seasonality
the tilt of the axis influences solar intensity and causes seasons
Global Circulation Patterns
-Hadley Cells
-Coriolis Effect
Hadley Cells
Areas where most intense radiation warms air and it rises and rains
-deserts 30 degrees
-rainforest at 0 degrees (equator)
Coriolis Effect
The Earth is spinning towards the east, this deflects the flow of hadley cells moving N or S
-in the N hemisphere they deflect to the right
-in the S hemisphere they deflect to the left
*merri-go-round: you spin faster on the outside edge and slower in the center
What way do objects deflect when viewing the pole from the top and entering an object in from the left?
deflects to the right
*gets accrued by the surface of planet and maintains its momentum but the area its going over on Earth changes speed
What causes bands of wind and which was does the weather move where we live?
the Coriolis effect
-we are in the W to E weather
Water Bodies
oceans and lakes hold heat and moderate weather conditions near by
-fairly stable as air heats and cools
Gyres
large ocean currents
Coastal Climates
areas influenced by nearby bodies of water
-coasts are cooler during the summer because breeze is cool coming from water
-coasts are warmer in the winter because breeze is warm coming from the water
as wind blows across water, water vapor gets picked up into the air and effects what?
precipitation pattern
Continental Climates
have no large bodies of water around and are far from coasts
-experience extreme temp. fluctuations
Topography
the physical elevational difference on the landscape and features of the landscape
-mountain ranges influence weather
Rain Shadow
an area with high evaporations in the shadow of the mountains
-on the downside of mountains
ex in north) black hills in the east
ex in south) andes in west
What defines terrestrial biomes
rainfall
-forests: >30” of rain/yr
-grass lands: 10-20” rain/yr
-deserts: <10”/yr
NE Iowa Climate
has temperature and precipitation fluctuations
-“founded where river, woodlands, and prairie meet”
Avg temp for Decorah
47 degrees F
Avg precipitation for Decorah
37.2”/yr
Aspects of NE Iowa location
-in the driftless, karst topography
-on an ecotone between temperature deciduous forest and prairies of Great Plaines
-pre-settlement: oak savanna and tallgrass prairie
ecotone
a transition from 2 biological communities (can be big- like temperate deciduous forest to prairies of Great Plain) (or small, like Anderson prairie to HRW)
what does Deciduous mean?
leaves drop and change color
How do we know what pre-settlement plant communities were here?
we look at pollen cores and public land survey records
pollen core
hollow tube into ground, analyze the layers of soil
pollen
male gametes (sperm) plants use to reproduce
2800 yr before present- present
about 50/50 pollen from trees and herbs so OAK SAVANNA
5400 yrs before present to 2800 years before present
little tree pollen, mostly herb prairie pollen so PRAIRIE
12,000 years ago to 5400 yrs before present
lots of tree pollen with herb pollen being mostly spring ephemerals (spring wildflowers) so DECIDUOUS FOREST
Where did historic reports come from?
Early explorers and early settlers
Public Land Survey Records
-Mid 1800s
-survey teams mapped out landscape, created maps, established a grid system in order to find where property was
Winneshiek County Land Survey
-20 townships
-6x6 miles
-each 1x1 mile section (36 per township)
How did people know where each section was?
at each cross section and each 1/4 of each cross section they used rocks and trees around to “bear witness”
What goes into “bearing witness” of a tree
-tree species
-diameter (size)
-distance from point
witness trees
the distance and point and species will tell us the plant community present
Tree Density numbers
<0.5 (praire) 29%
0.5-47 (savanna) 49%
47-99 (woodland) 10%
>99 (closed forest) 12%
ha
hector, 100 meters by 100 meters
Which factor best explains the distribution of plant communities?
precipitation, topography, rivers, and fire (all of these)
avg precipitation we get here and what that equivolates too
30-40”/yr = oak savanna
topography
shape and features of land surfaces
-north and south facing slopes
rivers
diff species of trees
ex) box elders and cottonwoods
-most river-bottoms and the river itself act as a BURN BREAK
fire
burns uphill and downwind
-in the past by lightning or Native Americans
-fire suppression, or not allowing fires to burn, have changed grasslands on hills here to forest
Forest
Tree Density: >99 trees/ha
Fire Frequency: Very low
Description: Trees may grow close together; many shade tolerant species such as basswood and maple
Cause: Without fire to kill young trees, a dense forest results. Shade intolerant species cannot persist.
Occurred in Iowa near rivers, on north facing slopes.
woodland
Tree Density: 47-99 trees/ha
Fire Frequency: Moderate (fires every few years, with gaps)
Description: Trees, but with some spacing. White oak, hickory
Cause: Fire occurs often enough that fire intolerant species cannot become big enough to survive. Was common in NE Iowa.
Savanna
Tree Density: 0.5-47 trees/ha
Fire Frequency: Frequent (fires usually every 2-5 years, but some gaps)
Description: Grassland, with scattered bur oaks
Cause: Frequent fires kill young trees; fire tolerant oaks establish when gaps occur. Was very common near Decorah.
Prairie
Tree Density: <0.5 trees/ha
Fire Frequency: Very frequent (few gaps, every 2-5 years)
Description: Grassland without trees except in sheltered areas, such as near streams or in rocky areas
Cause: Fires kill young trees; gaps are too short for even fire tolerant species to become large enough to survive. Most of Iowa west of Decorah.
biome
a large naturally occurring community of flora and fauna occupying a major habitat
ex) forest or tundra
nature deficit disorder
we are spending less time outside playing and exploring the natural world
