Predicting Light Regime Controls on Primary Productivity Across CONUS River Networks

Solar radiation is a fundamental driver of ecosystem productivity, but widespread estimates light available for primary producers in rivers are lacking. We developed model to predict river and used it estimate production across the contiguous United States (CONUS). Successively accounting riparian water column processes improved predictions as function light. calculated ratio width tree height this metric whether zones or most limit productivity over 2 million reaches. Water limited 50% nation's length 80% its surface area, with variations ecoregions related forest cover. Our findings facilitate large-scale stream well understanding controlling networks.