Responses of freshwater ecosystems to crude oil impaction

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5663671

Werner, M D

Responses of two freshwater lake ecosystems of the Intermountain West to crude oil impaction were investigated. Effects of crude oil on an ecosystem established in three phase laboratory microcosms (gaseous-aqueous-sediment), which simulated the natural lakes, were studied. Notable responses of the microcosm ecosystem to oil impaction included: an increased oxygen demand by the biological community, nutrient immobilization, a reduction in plant biomass accumulation and a heterotrophically dominated ecosystem. Nutrient immobilization, rather than toxic effects of oil on plants, was the primary factor leading to the long-term imbalance between autotrophs and heterotrophs following oil impaction. Crude oil reduced the rate and extent of in situ litter decomposition, but activity of oil-litter associated decomposer communities was greater than or equal to that of unoiled-litter over a year's period. Differences in the degree of crude oils' impacts between litter types and lakes were explained by factors such as biochemical structure of the plants, sediment types of the lakes and physical energy (e.g., wind) to the lakes. Increased rates of oxygen utilization because of the crude oil were identified as a potential primary detrimental effect of oil pollution. Crude oil did not affect the nutrient content of plant litter at any given stage of litter decomposition, but the rate of nutrient loss from the litter was reduced because of a reduction in the rate of litter decomposition.Of the nitrogen and phosphorus lost from plant litter, much less was released to ambient water in inorganic form from oiled litter than from unoiled litter. Nitrogen limitation to decomposers may have been the primary factor reducing the rate of oiled litter decomposition. Environmental ramifications of oil pollution concerning litter-environment nutrient exchange are discussed.

• OSTI ID: 5663671
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020900 -- Petroleum-- Environmental Aspects
520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AQUATIC ECOSYSTEMS
BIOLOGICAL EFFECTS
CHEMICAL REACTIONS
CONTAMINATION
DECOMPOSITION
ECOSYSTEMS
LAKES
MICROCOSMS
NUTRIENTS
OIL SPILLS
PLANTS
SURFACE WATERS