Time series data of carbon release in disintegrations per minute are presented for different nitrogen and phosphorus treatments with a high glucose concentration substrate added as a carbon source to soil samples from six depths (0-15, 15-30, 50-100, 100-150, 150-200 and 250-300 centimetres). Soil cores were collected from a field experiment in the Conwy catchment in July 2016 and returned the laboratories of the School of Environment, Natural Resources and Geography, Bangor University. A high molecular weight substrate was added as a carbon source to the samples and the rate of 14C-substrate mineralization measured. All the work was carried out by trained members of staff from Bangor University and the Centre for Ecology & Hydrology. The measurements were taken to improve understanding of the relationship between microbial activity and soil properties and depth of sampling, under differing nutrient availability. The data were collected for the NERC project 'The Multi-Scale Response of Water quality, Biodiversity and Carbon Sequestration to Coupled Macronutrient Cycling from Source to Sea' (NE/J011991/1). The project is also referred to as Turf2Surf. Full details about this dataset can be found at https://doi.org/10.5285/a15c35d7-0247-4ea3-820b-f6f20cc5ffed

In-lake temperature data for a peatland headwater lake of the Conwy catchment, North Wales are presented from November 2006 until December 2008. The Lake for which the data represents is Llyn Conwy situated on the Migneint blanket bog within Snowdonia National Park. The data is from a temperature string suspended from a buoy anchored above the deepest part of the lake. Temperature is recorded at 2 metre intervals throughout the lake profile from 1 to 19 m. The purpose of this data is to investigate water column stability and to determine when, and to what degree stratification/mixing occurs and to make inferences about the effect of this on productivity, nutrient and chemical cycling. Note: there are gaps in this data set due to equipment/battery failures and/or freezing of the lake surface which meant it was not accessible. Full details about this dataset can be found at https://doi.org/10.5285/7bb6c7df-7630-4621-a0d4-eacc3ec2202b

Discharge data and in-stream temperature for a peatland headwater stream of the Conwy catchment, North Wales are presented from March 2008 until July 2011. The stream for which the data represents is the Nant y Brwyn situated on the Migneint blanket bog within Snowdonia National Park. The purpose of the data is to calculate annual run-off estimates for the Nant y Brwyn catchment and to provide support for estimating fluvial carbon fluxes. Note: there are gaps in this data set due to equipment/battery failures and/or freezing of the stream. Note dates added to dataset name on 22/06/2017 Full details about this dataset can be found at https://doi.org/10.5285/cd7db09f-edf6-4b06-b878-f1be6c649e3a

Surface water quality data for the Conwy catchment, North Wales are presented. The data cover stream and estuary survey locations sampled manually from 2007 to 2011 at varying intervals between fortnightly and quarterly. Survey locations were selected as draining the main landscape classes in the catchment, which include upland (>300m) and lowland (<300m) environments under trees, moorland or improved agriculture. Also included are a suite of locations on the major rivers, and in the estuary. The purpose of the data is to provide support for estimating loads and testing hypotheses relating to the relationship between subcatchment properties and water quality, and the relative importance of mixing and in-stream processes in influencing downstream water quality. Streams draining peat, with high dissolved organic carbon concentrations, are well represented. Upland drainage is generally acidic, and lowland circum-neutral. The lowland rivers are not heavily contaminated with nutrients, although they show evidence of some loss of nitrates in particular. There is little industry in the catchment beyond agriculture and tourism, though there is some legacy contamination from metal mines in a small part of the catchment. Measurements are provided for major cations and anions, pH, alkalinity, DOC, Al, Fe and conductivity for most samples, with values for a wide range of trace elements for a limited number of samples. Full details about this dataset can be found at https://doi.org/10.5285/c53a1f93-f64c-4d84-82a7-44038a394c59

The data consists of plant structural plant community measurements from fifteen sites located in the Conwy catchment (North Wales) and from two sites in North West England. Annual aboveground net primary productivity (NPP), canopy height (cht), bryophyte cover (Bcov), leaf dry matter content (LDMC), leaf mass area (LMA) and specific leaf area (SLA) were measured on the dominant plant species. Data were collected in 2013 and 2014. The sites were chosen to represent habitat types and the terrestrial productivity gradient in Britain from intensive agriculturally managed lowland grasslands through to montane heath. Plots within the sites were located using a stratified random sampling design. Plant trait values were taken from existing published databases or were directly measured in each plot for the two species contributing the highest percentage cover. NPP (grams of dry mass per square metre per year) was measured using a variety of methods according to the plant functional types present. SLA and LDMC was measured on site focussing on the dominant vascular plant species in each plot defined as the two species contributing maximum standing biomass in the year of sampling. Leaf area was calculated based on scanned photographs analysed using Image J software v1.46r. Plant parameters were tested across a land use intensification gradient to detect parameters that can predict aboveground biomass production across different land management types. Data were used to enhance the predictions of biomass production in the Joint UK Land Environment Simulator model (JULES). Measurements informed the improvement of the nitrogen cycle component in the model. Measurements were undertaken by trained members of staff from Bangor University, the Centre for Ecology & Hydrology and Exeter University. This data was collected for the NERC project - The Multi-Scale Response of Water quality, Biodiversity and Carbon Sequestration to Coupled Macronutrient Cycling from Source to Sea (NE/J011991/1). The project is also referred to as Turf2Surf. Full details about this dataset can be found at https://doi.org/10.5285/8899768c-cc5a-4885-a88b-c08374ee568e