Lakes, Reservoirs, Physical Properties, and Water Chemistry Vocabulary

Vocabulary practice flashcards covering lake formation, morphometry, physical properties of light/heat, watershed features, and freshwater hydrochemistry concepts.

Lentic Ecosystem

A standing or still water ecosystem, such as a lake, pond, or reservoir.

Lotic Ecosystem

A flowing water ecosystem, such as a river, stream, or creek.

Paternoster Lakes

A series of glacial lakes connected by a single stream that resemble a string of rosary beads.

Tarn

A mountain lake or pool formed in a rock basin or cirque excavated by a glacier.

Moraine Lake

A lake formed when glacial deposits dam a valley or basin, preventing drainage.

Kettle Lake

A shallow, sediment-filled body of water formed by melting ice blocks left behind by a retreating glacier.

Caldera Lake

A volcanic lake formed by the collapse of land following a volcanic eruption.

Oxbow Lake

A U-shaped lake created when a wide meander of a river is cut off from the main channel.

Littoral Zone

The shallow shoreline area of a lake where light reaches the bottom, supporting rooted aquatic plants.

Pelagic Zone

The open water zone of a lake away from the shore where light penetrates for photosynthesis.

Profundal Zone

The deep water area of a lake located below the effective penetration depth of light.

Benthic Zone

The bottom region of a body of water, including the surface sediment and subsurface layers.

Bathymetric Map

A map that illustrates the underwater topography, depth contours, and physical shape of a lake bed.

Shoreline Development Index ($D_L$)

The ratio comparing the shoreline length of a lake to the circumference of a circle with an area equal to the lake.

Dimictic Lake

A lake that undergoes complete water mixing and turnover twice per year, typically during spring and fall.

Monomictic Lake

A lake that undergoes complete water turnover and mixing once per year.

Meromictic Lake

A lake that does not mix completely ($0$  times per year) due to permanent density or chemical stratification.

Polymictic Lake

A shallow lake that mixes frequently or continuously throughout the year.

Fetch

The continuous length of open water over which wind blows in a constant direction to generate waves.

Langmuir Circulation

Wind-driven vertical circulation in upper water layers forming parallel counter-rotating cells with alternating convergence and divergence zones.

Seiche

A standing wave in an enclosed or semi-enclosed body of water, causing water levels to rock rhythmically up and down.

Refraction

The bending of light as it passes from one medium to another of different density (such as air to water).

Attenuation

The logarithmic decrease in light intensity with increasing depth in a water column.

Watershed

The entire land area drained by a stream system or river network into a common outlet.

Paleolimnology

The scientific study of past inland water environments using physical, chemical, and biological sediment records.

Bicarbonate Equilibrium Diagram

Graph demonstrating the relative proportions of inorganic carbon species ($\text{CO}_2$, $\text{HCO}_3^-$, $\text{CO}_3^{2-}$) in freshwater across varying pH levels.

Dissolved Organic Carbon (DOC)

Organic carbon molecules in water small enough to pass through a filter with a pore size of less than $0.45\,\mu\text{m}$.

Particulate Organic Carbon (POC)

Organic carbon particles in water retained by a filter with a pore size greater than $0.45\,\mu\text{m}$.

Coarse Particulate Organic Carbon (CPOC)

Organic carbon particles in aquatic systems larger than $10\,\text{mm}$ in size.

Fine Particulate Organic Carbon (FPOC)

Organic carbon particles in aquatic systems ranging from $0.45\,\text{mm}$ to $1.0\,\text{mm}$ in size.

Liebig's Law of the Minimum

Ecological principle stating that organism growth is controlled not by total resources available, but by the scarcest essential nutrient.

Redfield Ratio

The atomic ratio of carbon, nitrogen, and phosphorus ($106:16:1$) required for balanced phytoplankton growth.

Stoichiometry

The study of the relative concentrations and quantitative balances of chemical elements in biological and ecological systems.

Nitrogen Fixation

The biological process of converting atmospheric nitrogen gas ($\text{N}_2$) into bioavailable ammonia ($\text{NH}_3$) or related forms.

Nitrification

The biological oxidation of ammonium ($\text{NH}_4^+$) into nitrite ($\text{NO}_2^-$) and subsequently nitrate ($\text{NO}_3^-$) by bacteria.

Denitrification

The microbial conversion of nitrate ($\text{NO}_3^-$) back into unreactive nitrogen gas ($\text{N}_2$) released into the atmosphere.

Oligotrophic

A freshwater classification describing low nutrient content, low biological productivity, clear water, and high dissolved oxygen.

Eutrophic

A freshwater classification describing high nutrient concentrations, high biological productivity, and abundant plant/algal growth.

Eutrophication

The process of excessive nutrient enrichment in a water body leading to algal blooms, light reduction, and oxygen depletion.

Point Source Pollution

Contaminants entering a water body from a single identifiable localized origin, such as a discharge pipe.

Nonpoint Source Pollution

Diffuse runoff pollution entering water bodies from broad, unlocalized areas, such as farm fields or urban surfaces.

Total Dissolved Solids (TDS)

The quantitative measure of all dissolved inorganic and organic substances present in a given volume of water.

Conductivity

The measure of water's ability to conduct an electrical current, which increases with higher dissolved ion concentrations.

Salinity

The total concentration of all dissolved mineral salts present in water.

Turbidity

A measure of the relative clarity or cloudiness of liquid caused by suspended particulate matter, expressed in Nephelometric Turbidity Units (NTU).

Dissolved Oxygen (DO)

The concentration of free, non-compound oxygen gas dissolved in water, expressed in $\text{mg/L}$ or percent saturation.

Anoxic

An aquatic environment completely lacking dissolved oxygen.

Supersaturation

A condition where water holds a concentration of dissolved gas greater than its equilibrium concentration at a given temperature and pressure.