The pristine conditions and the often simplified biotic communities of the Arctic offer unique opportunities to study aquatic processes and biological interactions. Arctic freshwaters need to be studied not only because of the opportunity to determine fundamental relationships but also to supply information to managers and governing groups so that plans can be made for the best possible use of aquatic resources. Nine investigators will measure changes in the ecology of rivers and lakes in Arctic Alaska caused by experimental manipulations of nutrients and fish populations. The integrating concepts are that changes of rate of nutrient supply at the bottom of the food change and of fish populations at the top of the food chain have direct effects on algal and fish populations, and indirect effects up and down the food chain. Experiments manipulating nutrient and fish concentrations will be conducted using whole and divided lakes, large enclosures, and whole streams. Results will provide a better understanding of how rivers and lakes are regulated and will enable better predictions of how the resources of Arctic lakes and rivers will respond to human disturbances.
