Aquatics: 1_Hydrology and Aquatic Environments Flashcards
(20 cards)
What is Thermal Stratification?
The formation of distinct layers of water in a lake due to differences in temperature and density.
What is the Epilimnion?
The shallowest, warmest, and most oxygenated layer of water in a stratified lake.
What is the Hypolimnion?
The deepest, coldest, and densest layer of water in a stratified lake, often with low dissolved oxygen.
What is the Metalimnion?
The transitional zone between the epilimnion and hypolimnion in a stratified lake.
What is the Thermocline?
The point within the metalimnion where the greatest temperature (and density) difference occurs.
What is Lake Turnover?
The process where a lake’s water layers mix, typically in the fall and spring, allowing for the redistribution of oxygen and nutrients.
What are Hydrogeological Regions?
Areas defined by similar physiography, geology, and climate that influence groundwater movement, availability, and quality.
What are Buried Valley Aquifers?
Permeable sand and gravel deposits located within ancient bedrock valleys that were subsequently buried by glacial sediments, serving as important groundwater sources.
What is Diamicton?
A type of sediment containing a mixture of particle sizes, from clay to boulders.
What is Till?
A diamicton specifically deposited by glacial ice.
What is an Aquitard?
A geological layer that restricts groundwater movement, though it may contain localized aquifers.
What is an Aquifer System?
Several geological layers that collectively function as an aquifer.
What are PAHs (Polycyclic Aromatic Hydrocarbons)?
A group of chemical compounds produced by the burning of organic matter, often found after wildfires.
What is Hydrophobicity?
The property of soil to repel water, which can occur after severe wildfires due to the condensation of gases from burning vegetation.
What is Turbidity?
The cloudiness of water, often increased after wildfires due to increased sediment and ash runoff.
What is Reservoir Sedimentation?
The accumulation of sediment in reservoirs, which can reduce their storage capacity and useful life.
What are Ecosystem Engineers?
Organisms that significantly modify their habitat, like beavers.
What are Beaver Channels?
Excavated pathways by beavers within and extending from ponds, increasing pond perimeter and volume.
What are Riparian Edges?
The transitional areas along the margins of water bodies where land and water meet.
What are Pond Levellers?
Devices consisting of pipes and a cage placed through a beaver dam to maintain a constant pond level and prevent flooding while allowing the pond to remain.
