DOI: 10.23637/rothamsted.99192
title: CO2 fluxes from three different temperate grazed pastures using Eddy covariance measurements

description: This dataset contains gap-filled carbon dioxide (CO2) fluxes, non gap-filled methane (CH4) fluxes, and all wind, meteorological and QC variables from three different pastures to produce 30-min mean flux rates of Net Ecosystem Exchange (NEE) for 2017-2019. The pastures were part of the North Wyke Farm Platform, and differed in the species they contained; each were grazed by cattle and sheep. Raw data, collected by eddy covariance and other instrumentation, included CO2, photosynthetic active radiation, incoming and reflected radiation, humidity and air temperature, soil heat exchange, soil moisture and temperature, and precipitation. These data were processed by gap-filling where necessary, using external data sources. 

The raw data are available elsewhere (http://resources.rothamsted.ac.uk/farmplatform). A full description of methods, and summary information for the years 2017 and 2018, can be found in the manuscript https://doi.org/10.1016/j.scitotenv.2022.154819. The code used to process the raw data (written in R) is available at https://rpubs.com/North_Wyke_Farm_Platform/970790.
description: The three pasture fields surveyed in this dataset are part of the North Wyke Farm Platform (NWFP). The NWFP has various production systems, or farmlets, which each operate in the manner of a separate farm in regards to inputs and outputs. Each farmlet is hydrologically isolated and contains a wide range of instrumentation, which together with additional surveys, provide data on hydrology, nutrient cycling and productivity of the farmlets. During the period covered by this dataset, the farmlets were as follows. The ‘green’ farmlet was permanent pasture, which had been in place since before 2011. The ‘red’ farmlet was sown with high sugar grass (perennial ryegrass, Lolium perenne cv. AberMagic), and the ‘blue’ farmlet was sown with white clover (Trifolium repens cv. AberHerald) and Lolium perenne cv. AberMagic. The fields were grazed by beef cattle and sheep, and cut for silage. The three fields in this dataset were one from each of the three farmlets and were part of a ‘triplet’ system, meaning that the timing of grazing or silage operations on the fields were coordinated as far as was practical to do so. Full details of the design of the NWFP can be found at https://doi.org/10.23637/rothamsted.98y1x. Fertilizer application data can be found on the NWFP data portal (http://resources.rothamsted.ac.uk/farmplatform), and a guide to the field events data is at https://doi.org/10.23637/rothamsted.98y4z. 

Eddy covariance towers were installed on each of the fields in 2016. A full description of the data collection from them, including their heights and locations, are given in a report (https://doi.org/10.23637/rothamsted.98y52) and a manuscript based on this dataset (https://doi.org/10.1016/j.scitotenv.2022.154819). Briefly, the eddy covariance measurements include a fast ultrasonic 3-D anemometer and a closed path CO2 analyser. Data collected in late 2016 were used for validation purposes, and continuous eddy covariance measurements commenced in Jan 2017. Alongside the eddy covariance measurements, the following data were collected: photosynthetic active radiation (PAR), incoming and reflected radiation, humidity and air temperature, soil heat exchange, and soil moisture and temperature. Precipitation data were also recorded at an automated weather station close to all three fields, for more details see https://doi.org/10.23637/rothamsted.98y4w. These raw data are available on the NWFP data portal (http://resources.rothamsted.ac.uk/farmplatform).
description: For full details, please refer to the associated manuscript https://doi.org/10.1016/j.scitotenv.2022.154819 and the R code for processing this data https://rpubs.com/North_Wyke_Farm_Platform/970790.