• Energy Research

This dataset contains time series observations of surface-atmosphere exchanges of net ecosystem carbon dioxide exchange (NEE), sensible heat (H) and latent heat (LE), and momentum (τ) measured at a field of winter wheat in Lincolnshire, UK during the 2012 growing season. Turbulent flux densities were monitored using the micrometeorological eddy covariance (EC) technique between 5th April 2012 and 8th August 2012. The dataset includes ancillary weather and soil physics observations, as well as variables describing atmospheric turbulence and the quality of the turbulent flux observations. Turbulent flux densities were calculated from the raw EC data using the EddyPRO® Flux Calculation Software Version 6.1. Quality Control of EC data involved removal of statistical outliers and tests that theoretical requirements for the successful application of the EC technique were not violated significantly. Data gaps in EC data (NEE, LE, H) and the partitioning of NEE into gross ecosystem production and total ecosystem production were performed using the REddyProc Package for R (Reichstein et al., 2019). Further details are available in the supporting documentation.

Soil cores of 8cm diameter and depth were collected from each plot near the base of Calluna vulgaris on the 1st April 2015, then transported back to Bangor at 4°C. Cores were cut from the top into 1 cm deep subsections. Each subsection was soaked and agitated to break up the root/soil clumps. Roots confidently identified as C. vulgaris were removed by hand and thoroughly washed in tap water. Necrotic or rotting roots were discarded. WinRHIZO version 3.2 was used to measure the length and diameter of cleaned subsection roots on a flatbed scanner. Roots were positioned without overlapping, submerged in 5 mm tap water to improve scanning accuracy. Acquisition parameters were set using the TWAIN interface in professional mode: positive film, 24 bit and 300 dpi. Post scanning, ten of the finest roots were manually selected from each subsection for microscopic investigation. The remaining roots were oven dried at 70°C for 24 hours, producing dry weight data for those < and > 2mm in diameter. All core fragments for microscopic assessment were soaked over 20 hours in 10% Potassium hydroxide (KOH). Roots were thoroughly rinsed in deionised water and heated in a water bath at 90°C for 15 minutes in 5% vinegar-ink solution. Roots were rinsed in three changes of tap water, acidified and de-stained by soaking in tap water with a few drops of vinegar for a further 20 minutes. A compound microscope was used to estimate proportional colonisation using the magnified intersection technique, with a scale bar cuticle instead of cross-hair and at a 40x magnification. Roots were cut approximately 1-2 cm in length, with 2 mm passes made along each root length. All cortical cells were examined for Ericoid mycorrhizae (ErM) and dark septate endophyte (DSE), working through the plane of focus. Each interval was categorised based upon ErM colonisation into 0 %, < 1 %, < 10 %, < 50 %, > 50 % and > 90 % colonisation. Data were transferred into an Excel spreadsheet. Data were exported as a comma separated value file for ingestion into the EIDC. This dataset contains root length, biomass and fungal colonisation data for Calluna vulgaris from control, drought and warming treated soils from the long term climate change experiment in Clocaenog forest. Soil samples were collected from the climate change experiment in Northeast Wales during April 2015. Roots were separated from the soil, their length and biomass measured and then analysed using microscopy for Ericoid mycorrhizae (ErM) and dark septate endophyte (DSE) colonisation of Calluna vulgaris. The experimental field site consists of three untreated control plots, three plots where the plant canopy air is artificially warmed during night time hours and three plots where rainfall is excluded from the plots at least during the plants growing season (March to September). The Climoor field experiment intends to answer questions regarding the effects of warming and drought on ecosystem processes and has been running since 1999. The root length and fungal colonisation data aims to understand how changes in soil hydrological and chemical properties have influenced Calluna vulgaris rooting behaviour and interactions with the soil microbiome. This work was supported by the Natural Environment Research Council award number NE/R016429/1 as part of the UK-SCAPE programme delivering National Capability.

The data resource comprises of two datasets. The first dataset comprises of fortnightly measurements soil respiration, soil temperature, soil moisture and photosynthetic activity. The second data set comprises of fortnightly measurements of rainfall, throughfall and water table depth. Data were collected from the climate change field site Climoor that is located in Clocaenog forest, Northeast Wales during 2015 and 2016. The experimental field site consists of three untreated control plots, three plots where the plant canopy air is artificially warmed during night time hours and three plots where rainfall is excluded from the plots at least during the plants growing season (March to September,) All measurements of this dataset have been carried out every fortnight if not indicated otherwise. Rainfall in millimetres (mm) was measured at the site using a ground-level rain gauge. Rain throughfall (in mm) was measured in each plot using a funnel-bottle construction to collect rain water in the plant canopy. Water table depth was measured for each plot using a measuring tape. Soil respiration and related soil temperature and soil moisture were measured in three areas of each plot. Soil respiration was measured in pre-installed opaque soil collars (20 centimetre diameter) that were installed in 1999. An infra-red gas analyser (EGM-4) was used. Photosynthetic active radiation was measured above the canopy while the soil respiration measurement was conducted. The measurements were carried out by different groups of CEH Bangor staff. The Climoor field experiment intends to answer questions regarding the effects of warming and drought on ecosystem processes. Plot level soil respiration measurements are important to investigate soil carbon dynamics and changes in soil carbon cycling and storage under the imposed climatic treatments. More detailed information about the field site, measurements and related datasets can be found in the supporting documentation. Soil respiration data for 1999-2015 are available from https://doi.org/10.5285/4ed6f721-b23b-454e-b185-02ba54d551f0 Rainfall was collected using a ground-level rain gauge at the site that was emptied fortnightly. Volumes were recorded in millilitres (mL) and converted to millimetres (mm). Throughfall was measured in each plot using a funnel-bottle construction. Volumes were recorded in mL and were converted to mm. Water table depths was measured in pre-installed tubes using a measuring tape. The distance from the water surface to the soil surface was measured and subsequently converted to water table depth in centimetres.. Soil respiration was measured in pre-installed soil collars in three location in each plot using an infra-red gas analyser. The soil respiration measurement took 120 seconds and was recorded in grammes of Carbon dioxide per square metre per hour (g CO2-C m-2 hr-1). Values were then converted to mg CO2-C m-2 hr-1 and the three plot measurements were averaged to a plot average. Soil temperature and soil moisture were measured alongside the soil respiration measurement close to the pre-installed soil respiration collars. Soil temperature was measured using a thermometer, soil moisture was measured with a hand-held Theta-probe. Photosynthetic active radiation was measured above the canopy using a pyranometer. All results were entered into Excel spreadsheets. Results from all the analyses were combined into one Excel spreadsheet. Data were then exported from this combined Excel spreadsheet as .csv files for ingestion into the EIDC.