# Seagrass canopy height, water depth, chlorophyll-a concentration and other plant and water quality indicators in Coastal Waters of Texas

## Data Dictionary

### Annual Results, e.g., 2011_results

These folders include raw tier 2 sampling data starting from 2011 for Texas coastal waters related to seagrasses. Parameters measured include chlorophyll a concentration, water depth, dissolved oxygen, light attenuation, pH, salinity, secchi depth, water temperature, total suspended solids, seagrass canopy height, and seagrass percent cover. Typical species represented within the data include Halodule wrightii, Thalassia testudinum, Syringodium filiforme, Halophila engelmannii, and Ruppia maritima. Sampling takes place at 567 permanent stations in Aransas and Redfish Bays, Corpus Christi Bay, and Upper and Lower Laguna Madre.

All annual result files include these columns:

SiteUniqueID - Unique site identifier within the file
Latitude - Latitude in decimal degrees, based on the NAD 83 datum
Longitude - Longitude in decimal degrees, based on the NAD 83 datum

Additional columns per file are described below. Note that each file is prefixed with the year in the format YYYY_MeasurementType.csv, e.g., 2018_Chlorophyll.csv.

#### Chlorophyll.csv

Chla_ugL - chlorophyll-a concentration in micrograms per liter

#### Depth.csv

Depth_m - water depth in meters

#### _DissolvedOxygen.csv

DO_mgL - dissolved oxygen in milligrams per liter

#### _LightAttenuation.csv

Kd_m-1 - diffuse (or downwelling) coefficient of light attenuation measured in units of per meter

#### _pH.csv

pH - pH

#### _QuadratPercentCover.csv

PcovHalodule - percent cover in a 0.25 square meter quadrat of Halodule wrightii
PcovThalassia - percent cover in a 0.25 square meter quadrat of Thalassia testudinum
PcovSyringodium - percent cover in a 0.25 square meter quadrat of Syringodium filiforme
PcovHalophila - percent cover in a 0.25 square meter quadrat of Halophila engelmannii
PcovRuppia - percent cover in a 0.25 square meter quadrat of Ruppia maritima
PcovallGrass - percent cover in a 0.25 square meter quadrat of all seagrasses
PcovBare - percent cover in a 0.25 square meter quadrat of bare areas

#### _Salinity.csv

Salinity - salinity (dimensionless)

#### _SeagrassCanopyHeight.csv

CanopyHalodule_cm - canopy height of Halodule wrightii in centimeters
CanopyThalassia_cm - canopy height of Thalassia testudinum in centimeters
CanopySyringodium_cm - canopy height of Syringodium filiforme in centimeters
CanopyHalophila_cm - canopy height of Halophila engelmannii in centimeters
CanopyRuppia_cm - canopy height of Ruppia maritima in centimeters

#### _SecchiDepth.csv

SecchiDepth_m - secchi depth in meters

#### _Temperature.csv

Temperature_C - water temperature in degrees Celsius

#### _TotalSuspendedSolids.csv

TSS_mgL - total suspended solids in milligrams per liter

### CarbonNitrogenPhosphorus

These data include carbon, nitrogen, phosphorus, and stable isotope measurements in Upper and Lower Laguna Madre Lagoon, and the Mission-Aransas Estuary which is part of the The National Estuarine Research Reserve System (NERR).

The files include:

* HW_isotopeCNP.csv - measurements for Halodule wrightii from 2011-2023
* TT_isotopeCNP.csv - measurements for Thalassia testudinum from 2011-2023

All of these files include these columns:

OID2 - internal identifier
UniqueID - Unique site identifier within the file
System - estuary or lagoon sampled; values include LLM (Lower Laguna Madre), ULM (Upper Laguna Madre), and NERR (Mission-Aransas Estuary, which is part of the The National Estuarine Research Reserve System)
Year - year sampled in YYYY format
Species - species sampled; values include Tt (Thalassia testudinum) and Hw (Halodule wrightii)
PercentC - percent carbon
umoleC_per_mg - micromoles of carbon per milligram
d13C - carbon isotope ratio value
PercentN - percent nitrogen
umoleN_per_mg - micromoles of nitrogen per milligram
d15N - nitrogen isotope ratio value
PercentP - percent phosphorus
umoleP_per_mg - micromoles of phosphorus per milligram
C_to_N - carbon to nitrogen ratio
C_to_P - carbon to phosphorus ratio
N_to_P - nitrogen to phosphorus ratio
Latitude - Latitude in decimal degrees, based on the NAD 83 datum
Longitude - Longitude in decimal degrees, based on the NAD 83 datum

### Little Bay

These data include seagrass measurements as a result of opportunistic sampling in Little Bay.

#### Little Bay 2012-2015.csv

StationsUniqueID - Unique site identifier within the file
Latitude - Latitude in decimal degrees, based on the NAD 83 datum
Longitude - Longitude in decimal degrees, based on the NAD 83 datum
Month_sampled - month sampled in numerical format, e.g., 8 for August
Day_sampled - day of the month sampled
Year_sampled - year sampled in YYYY format
Time - time sampled in 24-hour HHMM format
Depth_m - water depth in meters
SecchiDepth_m - secchi depth in meters
Temperature_C - water temperature in degrees Celsius
Salinity - salinity (dimensionless)
DO_mgL - dissolved oxygen in milligrams per liter
pH - pH
Chla_ugL - chlorophyll-a concentration in micrograms per liter
Kd_m2 - diffuse (or downwelling) coefficient of light attenuation measured in units of per meter
Pcov_Hw - percent cover in a 0.25 square meter quadrat of Halodule wrightii
Pcov_Tt - percent cover in a 0.25 square meter quadrat of Thalassia testudinum
Pcov_Sf - percent cover in a 0.25 square meter quadrat of Syringodium filiforme
Pcov_He - percent cover in a 0.25 square meter quadrat of Halophila engelmannii
Pcov_Rm - percent cover in a 0.25 square meter quadrat of Ruppia maritima
Pcov_Bare - percent cover in a 0.25 square meter quadrat of bare areas
CanopyHeight_cm - canopy height of seagrass in centimeters
TotalSuspendedSolids_mgL - total suspended solids in milligrams per liter
Notes - notes