In the limestone valleys of Central Pennsylvania, water quality issues often concern nutrient loading. Although nutrients can be a good thing--all streams need nutrients--too much of this "good thing" can have a huge negative impact on a stream. Excessive nutrients from manure, septic systems, and fertilizers can enter a stream through groundwater and stormwater run off, resulting in expansive blooms of aquatic plants in the stream. When these aquatic plants eventually die, their decomposition can locally deplete the streambed area of oxygen. Animals that can do so, leave these low oxygen settings. Less mobile animals, such as insect larvae and nymphs, cannot escape, and they die. With the annihilation of this potential food source, fish leave these stretches of stream.
Two important measurements of nutrients are concentration and load. The concentration of a nutrient, is its amount in a specific volume of water (often milliliters per liter). The nutrient load is the total amount of the nutrient passing through a particular cross-section of a stream during a specific time interval (often expressed in kilograms per day). Nutrient concentration is controlled by the nutrient load and the discharge of (amount of water flowing through) the stream. Aquatic plants and animals respond to changes in nutrient concentration, but nutrient loads can be important in accessing stream health and improvement.
Since 2002, researchers from the Geology Department of Juniata College have been measuring physical, chemical, and biological characteristics of Spruce Creek and Warriors Mark Run. These data, along with interpretations of spatial and temporal patterns, have been the keystone of completed and ongoing student/faculty research projects. Links to the data, interpretive maps, and research reports can be found below.