Goal 3: Determine the relative effects, mechanisms of activity, and management implications of multiple stressors in aquatic ecosystems.
(a) Determine the effects of contaminants on degradation of stream ecosystems, which contaminants have the greatest effects in different environmental settings and seasons, and evaluate which measures of contaminant exposure are the most useful for assessing potential effects.
(b) Determine the levels of nutrient enrichment that initiate ecological impairment, what ecological properties are affected, and which environmental indicators best identify the effects of nutrient enrichment on aquatic ecosystems.
(c) Determine how changes to suspended and depositional sediment impair stream ecosystems, which ecological properties are affected, and what measures are most appropriate to identify impairment.
(d) Determine the effects of streamflow alteration on stream ecosystems and the physical and chemical mechanisms by which streamflow alteration causes degradation.
(e) Evaluate the relative influences of multiple stressors on stream ecosystems in different regions that are under varying land uses and management practices.
Goal 4: Predict the effects of human activities, climate change, and management strategies on future water quality and ecosystem condition.
(a) Evaluate the suitability of existing water-quality models and enhance as necessary for predicting the effects of changes in climate and land use on water quality and ecosystem conditions.
(b) Develop decision-support tools for managers, policy makers, and scientists to evaluate the effects of changes in climate and human activities on water quality and ecosystems at watershed, state, regional, and national scales.
(c) Predict the physical and chemical water-quality and ecosystem conditions expected to result from future changes in climate and land use for selected watersheds.
SOURCE: Design of Cycle 3 of the National Water Quality Assessment Program, 2013-2023: Part 2: Science Plan for Improved Water-Quality Information and Management
3c, and 3d) because of their scientific importance but also partly because the scientific activities described in these objectives are intimately linked with one another (i.e., one cannot proceed without the other). Basic status and trends monitoring is critical to the proposed understanding studies. Thus, this assessment should also be considered within the committee’s overarching recommendation to, first and foremost, maintain status and trends assessment of water quality (i.e., Goal 1).