NEON aquatic organismal sampling: When to sample?

The National Ecological Observatory Network (NEON) is a national-scale research platform designed to assess the impacts of ecological change.  One significant challenge to this effort is defining standardized sampling strategies for streams, rivers, and lakes that are equally effective at sampling aquatic organisms, despite differences in channel morphology or hydrology.  A standardized temporal sampling strategy is necessary to best assess organismal diversity across diverse ecoclimates.  Variables influential to aquatic community structure include stream flow, degree days, and riparian greenness, gathered from published literature to create sampling windows for each site.  Proposed timing includes late winter/early spring, mid-summer, and autumn.