DATA_CODE

This item includes data and code used in the manuscript titled <i>A general phytoplankton-transport relationship in coastal aquatic systems </i>by Qubin Qin and Jian Shen.<br>Software needed: Most data were analyzed using MATLAB (version R2018b), and the volumes of the two study regions are calculated from bathymetric data using ArcGIS (version 10.7). <br><br>Data source: Monthly data of chlorophyll a concentration, salinity were collected at the main-channel long-term monitoring stations in Chesapeake Bay and its tributaries by the Chesapeake Bay Program (http://www.chesapeakebay.net/). Except for salinity, only surface data of other variables (0.5 m below the water surface) were used. The river discharge data at the fall-lines were collected by the United States Geological Survey (https://waterdata.usgs.gov/nwis/nwis). The volumes of the two study regions were determined based on USGS/NOAA bathymetric data and navigation charts.<br>Sampling information: chlorophyll a concentration and salinity were measured at fixed long-term monitoring stations during each cruise (one or two cruises for each month). For the upper-middle Chesapeake Bay, data from 1984-2015 were collected at 10 stations within the region. For the tidal freshwater James River Estuary, data of chlorophyll a concentration from 1990-2013 were collected at 6 stations. Such large data sets of multiple years also allow there are enough good and robust data for demonstration even data in a few years are not good due to uncertainties in data collection and calculation.