Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: Nitrogen and Phosphorous Estimates from Fertilizer and Manure, 2012
Description
This tabular data set represents estimated loads of nitrogen and phosphorous from fertilizer and manure applied on agricultural land for the year 2012 compiled for two spatial components of the NHDPlus version 2 data suite (NHDPlusv2) for the conterminous United States; 1) individual reach catchments and 2) reach catchments accumulated upstream through the river network. This dataset can be linked to the NHDPlus version 2 data suite by the unique identifier COMID. The source data for estimated loads of nitrogen and phosphorous from fertilizer for 2012 was produced by Brakebill and others, (USGS, 2017) and the source data for estimated loads of nitrogen and phosphorous from manure for 2012 was produced by Gronberg and others, (USGS, 2017). Units are kilograms. Reach catchment information characterizes data at the local scale. Reach catchments accumulated upstream through the river network characterizes cumulative upstream conditions. Network-accumulated values are computed using two methods, 1) divergence-routed and 2) total cumulative drainage area. Both approaches use a modified routing database to navigate the NHDPlus reach network to aggregate (accumulate) the metrics derived from the reach catchment scale. (Schwarz and Wieczorek, 2018).