Exam 3 Flashcards
stratification of lakes
layering of water based on temperature
epilimnion
surface water, warmest in summer, coldest in winter
metalimnion
middle layer of lake
hypolimnion
bottom layer of water, coldest, oxygen deprived
low productivity of water
oligotrophic, clear
high productivity of water
eutrophic, not clear
middle productivity of water
mesotrophic
littoral zone
close to shore, terrestrial plants
limnetic zone
open water
benthic zone
bottom of lake
pelagic zone
portion of euphotic zone with oxygen and light
photic zone
light can penetrate
aphotic zone
no light can penetrate
riverine zone in reservior
farthest from dam
high flow, shallow, narrow, turbid, organics from outside
lacustrine zone in reservior
closest to dam
minimal flow, deep, wide, clear, organics from within
when are nutrients highest in reservior?
highest after flooding event, trophic upsurge then trophic depression
ecological roles of wetlands
Essential fish and wildlife habitat
Water storage to mitigate flooding and erosion
Reduce sediment and nutrients to improve water quality
Sequester atmospheric carbon
Groundwater recharge
what do fish use wetlands for?
Spawning, nursery, migration
ephemeral wetland
wet only in spring
important functions of riparian zone on streams
link food webs, reduce erosion
effect of clear cutting on riparian zones
increase sediment loading and temp
common stream degradation issues
Sedimentation
Habitat loss
Increased BOD
Altered channel morphology
Flooding
Fish death
toxins
point-source pollution
problem attributed to specific location
non-point source pollution
no one single source can be identified
which species of trout is more tolerant of low DO and warmer temps
brown trout
trout distribution in streams
Brook are more prevalent in headwaters
Brown are further downstream in wider, warmer waters
what kind of trout survives better in streams
wild trout
common harvest regulations for trout in wisconsin
Creel and length limit
Gear restrictions
Stream specific
some reasons for removal of wildlife
Overpopulation
Nuisance
Increase growth
Exotic species
Disease control
Undesirable effects on habitat
Reduce competition with desired species
introductory stocking
introducing new species or to new area
maintenance stocking
limited or no natural reproduction
supplemental stocking
response to poor recruitment, game popularity
creel/bag
number of animals that can be taken in a day
possession limit
number of animals you can have at one time
why are creel limits uneffective
do not control effort or pressure
exploitation of walleye
35%
are gavis point paddle fish open or limited entry
limited entry
how to catch a paddlefish
snagging
why did Lake Oahe regs not protect larger walleyes
larger walleye did not have enough food so would have died anyway
causes of collapse in whitefish fishery
logging and overfishing
causes of whitefish recovery
Sea lamprey control through lampricides and trapping
Clean water act in 1972
challenges of managing whitefish
Whitefish move around a lot
Different user groups: commercial and recreational fishing
Inter-jurisdictional management: MI, WI, CORA
how can diversity be quantified
5 to 10% species
10 to 20% genera
15 to 30% family
two effects of inadequate soil volume on tree growth and longevity
Small growth and reduced longevity
benefits of the urban forest
Shade water interception energy conservation
Aesthetics air pollution reduction reduction in violence
Human health
four variables used to account for the compensatory value of a landscape tree
Size
Condition
Location
Species
Where should the structural roots (first set of roots that originate from the stem) be at planting
1-3 inches of the soil surface
symptom
plant expression to problem
sign
actual agent (insect, fungus, the thing that causes the plant disorder)
dutch elm disease symptoms
canopy leaf flagging, leaf yellowing to browning
oak wilt symptom
canopy leaf loss and outer leaf tanning and inner leaf often green
how is dutch elm disease passed
fungus spores travel on elm bark beetle
how is oak wilt passed
root grafts from infected trees
sanitation
taking care of diseased trees
sustained yield
Management intensity that provides for perpetual production of outputs
sustainable forestry
Capacity of forests to maintain their health, productivity, diversity, and integrity in the long run in the context of human activity and use
manage wetlands for wildlife
Preserve existing and reclaim altered wetlands
Maintain food and cover for desired species
Manipulate waters levels and vegetation
effects of flooding wetland
set back succession and draw water birds
effects of drawdowns
speed up succession, attract terrestrial wildlife
why are wetlands important for wildlife
half of endangered species live in wetlands
when did urbanization occur
8,000 years ago
urban exploiter
occur throughout urban areas, flexible needs, highest densities in urban areas
urban avoider
sensitive to human activities, rarely occur in margins/remnants
urban tolerant
use anthropogenic resources, but don’t take full advantage, suburbs, low densities
urban dependants
need humans to provide food/cover, urban core rarely elsewhere
What causes wildlife to be listed as endangered or threatened?
Species depletion from habitat loss/degradation and overexploitation
California condor
lead poisoning, DDT, habitat degradation
black footed ferret
habitat loss (depletion of prairie dogs) and disease
Endangered species act, 1973
Goals: Self-sustaining wild populations, maintain species integrity
Listing criteria
Protect critical habitat
Develop recovery plans
CITES: convention on international trade of endangered species
Designed to prevent animal trafficking
No trade: threatened with extinctions
Regulated trade: unlikely to go extinct
Countries list native species within their border
