Aquatic Ecology final Flashcards Preview

Biology > Aquatic Ecology final > Flashcards

Flashcards in Aquatic Ecology final Deck (324)
Loading flashcards...
121

EBS zooplankton ∂15N

must be determined for baseline
higher in N EBS- upwelling? predatory?

122

Juvenile Sockeye Salmon ∂15N, EBS

warm years- up to 2 levels above zoop. = piscivory
cool years- remain small, stay near shore, can't grow enough to move up food chain

123

Juvenile Pink Salmon Trophic position above zooplankton, EBS

pink salmon normally zooplanktivorous..
in wam years- up to 2 levels above zoop., piscivorous

124

Juvenile Chum Salmon trophic position above zooplankton, EBS

chum usually feed on jellies
warm event- up to 2levels above zoop., piscivorous

125

Signatures in northern Bering Sea

warm year- less negative ∂13C, near terrestrial loading (from Yukon river)
cool year- more negative ∂13C, pelagic source
not really a pattern in ∂15N

126

Signatures in Southern Bering sea

Warm- higher ∂15N, higher trophic position, trophic enrichment
Cool- lower ∂15N, lower trophic position

127

sediment ∂15N profiles from NH lakes

26 profiles, almost all show drop in ∂15N since 1900 = depleted N signature from fertilizer use! recall (fertilizer is from atmospheric N2)

128

global fresh water

3%
99.7% of that 3% is unavailable (glaciers, deep aquifers)

129

Where is our available water

80% is in 20 large lakes
95% is in 145 lakes

130

water demand per person

1400-1800m^3/person/year
(1.4-1.8million L)

131

unequal distribution of water

little water in some parts of China, France, unglaciated US
abundant in Canada, Scandinavia, NZ, Russia

132

Water required for some crops

70L for 1 apple
50L for 1 orange
140L for 1 cup coffee
2300L per kg rice
15,500L per kg beef

133

water exchange times, lakes basin

days - centuries
balance of inflow, precipitation, evaporation

134

water balance affected by

dams, diversions

135

Aral Sea

1.3million km^2 watershed
before 1960, 4th largest lake in world 67,000km^2
Kazakhstan and Uzbekistan

136

Aral Sea, 1920s

water diversion for agriculture (especially cotton), storage for hydroelectric power

137

Aral Sea ppt

historically- 10ppt
Now- 34ppt (Ocean salinity!)

138

Aral Sea, since 1960s

85% volume lost (42,000km^2 lost)
65% SA lost
lakeside towns now 100-150km away
former lake area dry, saline

139

Affects of Aral Sea changes

all fish species gone
60,000 fishing jobs lost
massive ecological change- species extinctions
local climate substantially changed

140

Aral sea historic harvest

48,000T/yr
largest fish processing plant in USSR

141

Aral Sea 2000's

area 24,000
volume 175
salinity 65-70
separated in to two lakes in 1993
2010, only 1 lake left

142

Economic Consequences of Aral Sea loss

fishing, agriculture, cost of water rights

143

Health Consequences of Aral sea loss

highest child mortality in former USSR
life expectancy decrease 64-51yrs (in ~60yrs)
highest world rate of esophageal cancer
widespread DNA damage
birth abnormalities 5X EU, infertility

144

What's causing the health consequences, Aral Sea

large volume of agricultural chemicals, waste
carcinogenic salt/chemicals transported by wind

145

Pesticide use in Aral sea area

72kg/ha
compared with US- 1.6kg/ha

146

Valiant Dam Italy

265m concrete arch dam, steep walled mountain valley
built in 1960
limestone/clay layers = slides as reservoir filled

147

Vainont Dam, 1963

debris slide
displaced 30x10^6 m^3 water over dam (1/4 of contents)
2500 deaths downstream

148

China, S-->N water diversion

un-uniform water distribution
divert water from major S rivers to industrial in low water N
3X cost of Three Gorges
3 separate routes

149

Three Gorges Dam, China

once largest in world
flood control, diversion of water to N, hydro power, transportation

150

Three Gorges Dam problems

loss of agriculture, historical sites
changes to climate, public health, soil stability