Forests play an integral part in keeping our streams and rivers clean. Tree canopies shade and cool streams. Aquatic species depend on the oxygen that is dissolved in their water. Cooler stream temperatures mean more oxygen is available to the life within that stream. Unshaded streams result in warmer water temperatures that can increase the rate of photosynthesis by aquatic plants and algae, often allowing exponential growth in warm seasons.

Root systems cycle nutrients and trap sediments. Nitrogen and phosphorus are taken into the trees, rather than washed into our rivers. Without trees and streamside vegetation, nutrients wash downstream from creeks to rivers and ultimately, in this region of the country, to the Gulf of Mexico, where their overabundance has created a Dead Zone, where nothing survives.

Deep in UK’s Robinson Forest flows Cole's Fork, a headwater system for a 6,000-acre watershed, the largest in the Cumberland Plateau geographic region. Department of Forestry and Natural Resources students and researchers have taken a weekly water sample from Cole’s Fork for more than 50 years, measuring temperature, conductivity, dissolved solids, dissolved oxygen, pH, and oxidation reduction potential (a measure of the water's ability to neutralize contaminants). FNR’s long-term, continuous hydrological monitoring has resulted in data that the Environmental Protection Agency and the Kentucky Division of Water turn to for determining what water quality from undisturbed forest land should be.

Over the years, the data has revealed environmental trends. In the 1980s, acid rain had become a serious threat to our environment and our health. Acid rain can acidify streams and soils and change aluminum in the soil from a solid to a liquid that can be taken up by trees and ingested by fish. This not only results in death to vegetation and stream life but poses a health hazard for all the animals and humans who eat those fish.

To address the issue, new regulations were added to the Clean Air Act in 1989. Through both water and soil studies, FNR scientists were able to track the success of the new measures through their data. After the regulations went into effect, our researchers measured a 50% reduction in sulfates in the Cole’s Fork stream system.

The department has also conducted long-term logging studies in Robinson Forest to determine best management practices (BMPs) that protect water quality in our forests by reducing sediment runoff. Those BMPs have now been codified into law.

With both a resident hydrologist on its research and teaching faculty and an extension water quality specialist for outreach, our students and the wider community benefit from FNR’s research and outreach. Improving water quality for all Kentuckians is another part of our land-grant mission, a mission we take seriously.