Reed in the outlet of Lake Lockne.
The environmental quality of lakes and streams are measured on the basis of "ecological status" that can be "high," "good," "moderate," "unsatisfactory" or "bad". An assessment is made based on established parameters, which together lead to an overall picture of the environment. The aim is that all lakes and streams that are not artificial or heavily influenced by, for example, infrastructure or hydropower, should keep good ecological status. Good ecological status means that flora and fauna, streams, ground structures, beaches, and water quality must not show more than small deviations from what is considered natural conditions.
Both Lake Näkten and lake Lockne have "moderate ecological status" which means that the environment needs to improve to reach the objective – good ecological status. Lake Revsund reaches "good ecological status".
The clear water in the lakes is due to low proportion of wetlands in the basin, low levels of nutrients (nitrogen, phosphorus) and low concentrations of organic matter. When nutrients are added, for example by wastewater or surplus from fertilized agricultural land, it increases the amount of organic matter in the water by increased production of phytoplankton. The water becomes cloudy, the growth of reed increases and the oxygen content at the bottom decreases as the decomposition of organic matter consumes oxygen.
It should be noted that the natural concentrations of nutrients in these lakes are extremely low. This means that the lakes are particularly sensitive to raised nutrient levels. Even very small amounts will affect the ecosystem. Long turnover times (Näkten and Lockne lake) makes it especially important to work proactively to limit the introduction of nutrients and organic matter.