Biological test (Bioassessment)
test for pollution using living organisms, more accurate for determining long term impact
Chemical test
A procedure or chemical reaction used to identify a substance
Physical Measurements
Measurements of physical characteristics of the water body such as temperature, turbidity, rate of flow etc.
EPT / Midge Ratio
A biological test that looks for the presence of 3 orders of insects that are fairly sensitive to pollutants. If these indicator species are present the water is probably fairly clean, if no then there are likely problems. The species are Ephemeroptera, P
Simpson diversity index
Often used to quantify the biodiversity of a habitat. Takes into account the number of species present, as well as the abundance of each species
Pollution tolerance index
A Biological Test that looks at the number of species present that are tolerant to pollution in a waterway to determine if the water is clean or not.
Nitrate
any compound containing a nitrate group. It is needed by aquatic plants and plankton for growth. Too much of it is a sign that the waterway may have sewage or fertilizer runoff and may be prone to artificial eutrophication.
Alkalinity
Measures the natural buffering capacity of the body of water. Water with higher alkalinity is better able to neutralize acids and bases when they are added to the water and thereby keep a stable pH.
Eutrophic
lakes that are rich with organic matter and vegetation that are typically murky
Oligotrophic
a condition of a lake or other body of water characterized by low nutrients, low productivity, and high oxygen levels in the water column.
Dissolved oxygen
oxygen dissolved in water, dissolved oxygen is important for fish and other aquatic animals
Biological Oxygen Demand (BOD)
The amount of dissolved oxygen needed by decomposers to completely break down the organic matter in a water sample at 20 degrease over five days. A high BOD measurement is a sign of poor water quality and leads to low dissolved oxygen levels.
Phosphate
An essential nutrient for plant/algal growth. Usually in limited supply. Excess phosphate, such as that caused by fertilizer from agricultural runoff, can cause algal blooms because algae doesn't require much phosphate and grows rapidly when it is in larg
Macroinvertebrates
multicellular organisms that are visible to the naked eye, invertebrates areorganisms that lack a backbone such as insects, crawfish, worms
Watershed
Land area that delivers water, sediment, and dissolved substances via small streams to a major stream (river).
Dichotomous key
a key for the identification of organisms based on a series of choices between alternative characters
Secchi disc
a circular disk used to measure water transparency in rivers and lakes; measures turbidity
Turbidity
muddiness created by stirring up sediment or having foreign particles suspended
Field guide
a guidebook describing natural objects of some type that might be encountered in the field
Productivity
The synthesis of new organic material. That done by green plants using solar energy is called primary productivity.
Topography
The surface features of a place or region. The topography of a region includes hills, valleys, streams, lakes, bridges, tunnels, and roads.
littoral
the region of the shore of a lake or sea or ocean
limnetic
open water of a lake, no rooted plants but light penetrates
profundal zone
zone in a freshwater habitat that is below the limits of effective light penetration
Benthic zone
bottom of an aquatic ecosystem; consists of sand and sediment and supports its own community of organisms
Abiotic
nonliving, physical features of the environment, including air, water, sunlight, soil, temperature, and climate
Biotic
Pertaining to life; environmental factors created by living organisms
the optimal pH for aquatic organisms
A pH between 6.5 and 8.2 is optimal for most aquatic organisms.
mayfly
Ephemeroptera. slender insect with delicate membranous wings having an aquatic larval stage and terrestrial adult stage usually lasting less than two days. Intolerant of pollution
caddisfly
Trichoptera/Aquatic insect whose wings are shaped like a tent. Intolerant of Pollution
stonefly
Plecoptera. Primitive winged insect with a flattened body. Has an aquatic larval stage. Intolerant of pollution
Relative Humidity
the percentage of water vapor in the air compared to the maximum amount the air could hold.