OXYGEN IN LAKES, STREAMS,
AND RESERVOIRS
SOLUBILITY OF OXYGEN IN WATER
RELATIVE TO PRESSURE
SOLUBILITY OF OXYGEN IN WATER
RELATIVE TO TEMPERATURE
OXYGEN
SOURCES
• ATMOSPHERE
• PHOTOSYNTHESIS
LOSSES
• CHEMICAL
– HUMIC ACIDS
– IRON
• COMMUNITY METABOLISM
RED MUD – BLACK MUD
ORTHOGRADE OXYGEN CURVE
CLINOGRADE OXYGEN CURVE
CHANGE IN SEASONS IN A DIMICTIC
LAKE
HOW COULD TWO SIMILAR LAKES
HAVE SUCH DIFFERENT OXYGEN
PROFILES IN SUMMER?
CHANGE IN OXYGEN PROFILE
THROUGH A SUMMER SEASON
HETEROGRADE OXYGEN CURVES
SUPPOSE A LAKE HAS THE FOLLOWING
CLINOGRADE OXYGEN CURVE AT THE
END OF THE SUMMER SEASON
CASCADE OF EVENTS LEADING TO
TURNOVER WITH CHANGE IN OXYGEN
PROFILE
OXYGEN CONCENTRATION UNDER
CLEAR ICE
LATER IN WINTER
WARMING OF A LAKE DURING SPRING
AND EARLY SUMMER
LONGITUDINAL OXYGEN
CONCENTRATION IN A STREAM
DAILY OXYGEN CYCLE
OXYGEN CYCLE IN LAKE ERIE BASIN
LAKE NASSER
• Surface area [km2]
6,000
• Volume [km3] 162
• Maximum depth [m]
110
• Mean depth [m] 70
• Water level Regulated
Normal range of annual
water level fluctuation
[m] 25
• Length of shoreline
[km] ca. 9,000
• Catchment area [km2]
2,849,000
LONGITUDINAL PROFILE OF LAKE
NASSER
LAKE NASSER OXYGEN
OXYGEN DEFICIT INCREASES WITH
• INCREASED PHYTOPLANKTON PRODUCTION
• INCREASED PHOSPHATE
• INCREASE IN HYPOLIMNETIC VOLUME
OXYGEN DEFICIT PROPORTIONAL TO THE INVERSE
OF THE EPILIMNETIC TRANSPARENCY
Example: Diamond Lake in Oregon
DO DYNAMICS IN SURFACE WATERS
(WETZEL, TABLE 9-2)
STREAM
RESERVOIR
LAKE
DO
USUALLY HIGH
HIGH HORIZONTAL
VARIABILITY,
USUALLY WARMER
SMALL
HORIZONTAL
VARIABILITY,
USUALLY COOLER
OXYGEN UPTAKE
FROM
ATMOSPHERE
HIGH
MODERATE
VARIABLE TO LOW
DIURNAL
VARIATION IN
OXYGEN
HIGH
MODEST
LOW