Aquatic macroinvertebrates are water bugs that we can see with our naked eye. Many of these animals make their homes in rocks, leaves and sediment in stream beds. Different types of aquatic macroinvertebrates tolerate different stream conditions and levels of pollution. Depending on the types of macroinvertebrates found in a stream, predictions about water quality can be made. These animals are also an important part of aquatic and terrestrial food chains. Learn more about aquatic macroinvertebrates.
Dissolved oxygen is molecules of O2 that dissolve into water from the atmosphere or from oxygen release from plants during photosynthesis. It is invisible to our naked eye. Dissolved oxygen is what makes aquatic life possible. Without sufficient oxygen many fish and water bugs may die. Even a small change in dissolved oxygen concentration can affect the composition of aquatic communities. Learn more about dissolved oxygen.
Two nutrients that can have large impacts on water quality are nitrogen and phosphorous. Plants are able to use forms of of these nutrients to build proteins and grow. When waterways become over fertilized with nitrogen there can be heavy plant growth. Excessive plant growth can decrease the aesthetic value of the water because of the smelly decomposing mats of vegetation. Also, when bacteria decompose dead plant material they use up dissolved oxygen which is important for the survival of aquatic organisms. Learn more about nutrients.
Turbidity is a measurement of how much suspended material is in the water. Suspended solids prevents sunlight from reaching photosynthesizing plants which may reduce the amount of dissolved oxygen in the water. Fish and other aquatic life need this dissolved oxygen in order to survive. Heavy loads of suspended solids can make it hard for fish to see their pray and even clog fish gills and filter-feeding devices of water bugs. However, turbidity isn't always bad. All streams have a natural level of turbidity. Learn more about turbidity.
pH is a measurement of how acidic or basic something is. It is measured on a scale from 0-14. Acidic values are from 0-7, with 0 being the most acidic. Basic numbers are from 7-14. A neutral pH is 7. The pH scale is logarithmic. This means that each unit change (e.g., 5 to 6) is a tenfold change in the acidity of the substance. Water with a pH of 5 is 10 times more acidic than water with a pH of 6. Water with an extremely high or low pH is deadly. Water with relatively low pH (acidic) may reduce the hatching success of fish eggs and irritate fish and aquatic insect gills and damage membranes. Learn more about pH.
The temperature of water is a measure of how much heat energy the water contains. In the U.S. we usually use the Fahrenheit scale to measure temperature. However, scientists usually use the Centigrade (or Celsius) scale. The metabolisms of fish, bugs, and amphibians are cold-blooded. Their metabolisms speed up and slow down based on the surrounding temperature. If the temperature changes too drastically, their metabolisms may not function as well, decreasing their ability to reproduce and survive. Learn more about water temperature.
There are many types of bacteria that can be found in water. E. coli is a subgroup of coliform bacteria. Coliform bacteria are microscopic organisms. They originate in the intestinal tract of warm blooded animals and may also be found in soil and vegetation. E. coli, however, is only found in the intestines of warm blooded animals. Learn more about bacteria.
Invasive species are non-native species that threaten the diversity or abundance of native species due to their uncontrollable population growth, causing ecological or economic impacts. Not all non-native species are considered invasive species. Many non-native species are not able to spread or reproduce in natural habitats. Invasive species thrive in favorable environmental conditions that lack predators, competitors and diseases. Invasive species are also referred to as "nuisance" or "exotic" species. Learn more about invasive species.
Some examples of Pharmaceuticals and Personal Care Products (PPCPs) are prescription and over-the-counter drugs, cosmetics, sun screen products and vitamins. These products can enter our waterways by being flushed down toilets. Although dosages found in water are extremely low (in parts per trillion) there is concern that these products are contributing to health and environmental problems. Some adverse affects on fish and other aquatic life from this include delayed sexual development, abnormal hormone levels, and impaired reproductive systems and immune systems. Learn how to properly dispose of unwanted prescription drugs and learn more about PPCPs.