446 Aquatic Ecology Flashcards Preview

Biology > 446 Aquatic Ecology > Flashcards

Flashcards in 446 Aquatic Ecology Deck (279)
Loading flashcards...
31

dissolved P with time

low grazing = very low slope, barely increasing
intense grazing = high slope, increasing

32

why is there higher dissolved P with intense grazing

high grazing = lots of dissolved P b/c not being taken up by algae
size of fish controls [algae] which controls [dissolved vs. particulate P]

33

length of algae as a function of biomass of algae in large grazer system

as biomass increases, size increases (more removed = more nutrients available to the fewer)

34

length of algae as a function of biomass in small grazer system

increased biomass = smaller size (more biomass means higher quantity means less nutrients available to each)

35

algae size and phosphate turnover time

small algae (large grazer system) = slower nutrient turnover = long phosphate turnover time
large algae (small grazer system) = faster Phosphate turnover time

36

when you have large particles, the overall particle load

is made up of more large particles, median is higher
large particles = less small particles

37

add nutrients

overall particle size shift to larger particles
= long phosphate turnover time

38

add nutrients and fish

shift to more smaller particles
= shorter phosphate turnover time

39

so... as average size of plankton declines..

larger slope, uptake efficiency increases, turnover time is shorter
AND transparency declines

40

how changes in biology = changes in physics

thermal structure, penetration of light, accumulated energy/heat content

41

fetch

longest open length of a water body through which wind can blow

42

change in epilimnion with fetch

increased fetch = increased depth of epilimnion (more wind = more wind mixing)

43

downward heating intensity vs. penetration of solar radiation

increasing surface area of water body (fetch) vs. increasing water transparency

44

increasing fetch & transparency

deeper epilimnion, more heat, more energy, greater depth for photosynthesis, more O2

45

role of biology on mixing rate

affects clarity of lake which affects insolation absorption which affects stratification

46

sedimentation, total phosphorus rates highest in

+N (nutrients added, no small fish, large zooplankton)

47

secchi depth highest in

control then +N
deepest when no small fish

48

chlorophyll highest in

+NF (nutrients, small fish, small zooplankton grazers, larger algae)

49

summer O2 profile, control vs. +F

+F higher O2 in epilimnion
lower O2 in metalimnion and hypolimnion
O2 max is higher in water column in +F and goes to 0 with depth

50

summer O2 profile, +N, +NF

+N higher O2 at all depths
+NF goes to 0 in hypolimnion

51

lake St. George

large # planktivorous fish
low secchi depth
smaller daphnia
shallower epilimnion depth
higher TP
higher Chl
strongly eutrophic

52

Haynes lake

less planktivorous fish
deeper secchi depth
deep epilimnion depth
larger daphnia length
lower TP
lower Chl

53

Julian days

continuous count of days since the beginning of the day starting at noon on January 1

54

hypolimnetic oxygen changes with season

oxygen depletion from spring -- summer (lowest O2 with +F)

55

hypolimnetic oxygen chantes in Haynes lake and lake StGeorge

both reach min. in June, S.G. stays at ~0 for rest of summer, H. increases to second max in late July-early August. Lake H. never goes to 0

56

algae size and relative sedimentation rate

small grazer system = short phosphate turnover time = lower relative sedimentation

57

why larger grazer system has higher relative sedimentation

large things sediment more, greater proportion sink, heavier, less efficiently used (P turnover)

58

absolute sedimentation rates

would be higher in small grazer system because there's so much more

59

toxic algal groups

cyanobacteria, dinoflagellates, diatoms

60

problems with algal blooms

toxins, anoxia, habitat loss, recreational loss, health risks