tt.nee: Medium frequency concentration data and fluxes from...
In flux: Flux Rate Calculation from Dynamic Closed Chamber Measurements

tt.nee

R Documentation

Medium frequency concentration data and fluxes from non-steady state closed chamber measurements

Description

The data comes from the Trebeltal / Northeastern Germany and has been recorded with flexible transparent and opaque non-steady state closed chambers in 2011.

Usage

data(tt.nee)
data(tt.flux)

Format

tt.nee is a data.frame with 18 variables representing 14388 CO2 concentration measurements from 104 chamber placements.

tt.flux is a results table representing fluxes estimated with fluxx from tt.nee with 28 columns and 104 rows (= number of chamber placements in tt.nee). Contains many variables from tt.nee.

date: Factor giving the date of field sampling, format is "%Y-%m-%d".
time: Factor giving the time of measurement in the field, format is "%H:%M:%S".
session: (Unique) Session number identifying one chamber placement. Integer.
record: Integer, running number of concentration measurement within one session.
spot: Factor identifying the field measurement location.
PAR: Numeric. Photosynthetic photon flux density (PPFD).
t.cham: Numeric. Temperature logged inside chamber during concentration measurements
NEE: Numeric. CO2 concentration in chamber headspace.
t.air: Numeric. Air temperature outside chamber.
t.soil2: Numeric. Soil temperature at 2cm depth.
t.soil5: Numeric. Soil temperature at 5cm depth.
t.soil10: Numeric. Soil temperature at 10cm depth.
area: Numeric. Chamber area.
height: Numeric. Chamber height.
kind: Integer. Chamber kind. 1 = transparent chamber, 3 = transparent chamber with measurement before sun rise, 5 = opaque chamber
volume: Numeric. Chamber volume.
datetime: POSIXlt. Time stamp.
plot: Factor identifying the field plot (all TY1).
all: Factor. Combined unique identifier for chamber placement.
CO2.pv: Numeric. p.value of the fitted regression for the flux estimation.
CO2.r2.f: Logical numeric (0 | 1) giving the r2 flag. See fluxx for details.
CO2.range.f: Logical numeric (0 | 1) giving the range flag. See fluxx for details.
CO2.nrmse.f: Logical numeric (0 | 1) giving the nrmse flag. See fluxx for details.
CO2.ghg: Character. Greenhouse gas as submitted to fluxx via var.par.
CO2.unit: Character. Ouput unit of the flux as specified via out.unit in fluxx.
CO2.flux: Numeric. Flux
CO2.r2: Numeric. R2 of the model that has been used for flux estimation.
CO2.nrmse: Numeric. NRMSE of the model that has been used for flux estimation.
CO2.nomba.f: Numeric. Number of concentration measurements below ambient.
CO2.podpu: Numeric between 0 and 1. Propórtion of data points used.

Details

tt.nee contains medium frequency (measured online) CO2 concentration data from 3 spots with Typha angustifolia and includes data needed for modelling gpp/nne measured with transparent chamber and reco measured with opaque chamber. tt.flux contains fluxes estimated from tt.nee using fluxx.