The dataset contains hydrochemistry (temperature, specific conductivity, pH, dissolved oxygen) and nitrate-N in the Houzhai catchment (Southwestern, China). Three karst springs were investigated. Data were obtained via sensor approach with 15mins time interval between May 2016 to October 2017. Full details about this dataset can be found at https://doi.org/10.5285/f70596a1-0994-4b08-abab-0c9398af447d

Water quality modelled outputs for daily channel discharge and depth, nitrate-N, ammonium-N, suspended sediment concentration, total phosphorus, and soluble reactive phosphorus for the Mekong River basin. Baseline models for P and N were calibrated over 1998 to 2017. Predictions spanning 2018 to 2098 were modelled based on eight scenarios (2 climate x 2 socioeconomic x 2 population). Please see Whitehead et al (2019) https://doi.org/10.1016/j.scitotenv.2019.03.315 for details. Full details about this dataset can be found at https://doi.org/10.5285/710fc65c-87eb-4932-9d8e-dc8328742232

In two saltmarshes, Old Hall in the Blackwater (southeast England) and Warton Bank in the Ribble (northwest England), we took vegetation and soil samples every six to eight weeks from August/September 2024 to January 2025 to characterise seasonal denitrification and vegetation dynamics. The data includes, vegetation species and diversity; seawater and porewater samples (NO3-, NH4+, PO43-); seawater ion concentrations (Cl-, Na2+, K+, Br-, Mg3+ and Ca2+); moisture and organic matter content in the sediment. A key ecosystem service in coastal systems is the remediation of nutrient pollution through sediment burial, vegetative uptake and microbial processing. Denitrification is a facultative anaerobic process where microbial activity transforms nitrate (NO3-), which in high concentrations can be environmentally harmful, into the environmentally benign dinitrogen gas (N2). Denitrification's magnitude is considered particularly important in saltmarsh systems compared to other habitats, although an intermediate product, nitrous oxide (N2O), can also be given off and contribute to climate change. Full details about this dataset can be found at https://doi.org/10.5285/72962722-bd56-4b3e-b397-90ceec6c821e

Surface snow samples were collected daily from a Canadian high Arctic location at Eureka, Nunavut (80N, 86W) from the end of February to the end of March in 2018 and 2019. The snow samples were collected at several sites representing distinct environments: sea ice, inland close to sea level, and a hilltop ~600 m above sea level. Ion Chromatography (IC) analysis was performed for most of the snow samples. Snow salinity measurement is mainly for surface snow. Surface ozone was measured at sea level (from the Zero Altitude PEARL Auxiliary Laboratory (0PAL)) and lower tropospheric BrO (0-4 km) was measured by MAX-DOAS instrument (at ~610 m located at the Polar Environment Atmospheric Research Laboratory (PEARL)). This study was supported by the UK NERC Arctic office via two UK-Canada bursary programs: "The role of tundra snowpack chemistry in the boundary layer bromine budget at Eureka, Canada" (2018), and "A second investigation of the role of tundra snowpack chemistry in the boundary layer 'bromine explosion'" (2019). The Eureka MAX-DOAS BrO measurements made at the PEARL Ridge Laboratory by the Canadian Network for the Detection of Atmospheric Change (CANDAC) was primarily supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian Space Agency (CSA), and Environment and Climate Change Canada (ECCC).

This dataset contains nutrient data from soils and microbial biomass in soils from an experiment based at Winklebury Hill, UK. The experiment used seeds and plug plants to create different plant communities on the bare chalk on Winklebury Hill and tested the resulting carbon and nutrient cycling rates and compared these to the characteristics of different plant functional groups. The experiment ran from 2013 to 2016 and this dataset contains data from 2014 only. This experiment was part of the Wessex BESS project, a six-year (2011-2017) project aimed at understanding how biodiversity underpins the ecosystem functions and services that landscapes provide. Full details about this dataset can be found at https://doi.org/10.5285/5012d5c1-da82-4773-b286-01222595a8c8

This dataset provides weekly pollutant concentration and deposition data in cloud and rain samples from the, now retired, Bowbeat field site near Edinburgh, UK. The data were captured approximately weekly between 03/09/2003 and 28/06/2006 using a cloud droplet collector and rainwater collector. They were collected to monitor and model cloud/rain water composition and deposition at high elevation as part of ongoing routine measurements. Full details about this dataset can be found at https://doi.org/10.5285/2dca8f2f-a21b-4f77-bc8c-326269ab58d1

This dataset is from the Northern Ireland (NI) DELTA® Gas and Aerosol Monitoring Network, and consists of monthly atmospheric concentrations of inorganic, water-soluble, reactive gases and aerosols measured with the UKCEH DELTA® method at 4 sites across NI for the years 2019 to 2020. • Gases: ammonia (NH3), nitric acid (HNO3), sulphur dioxide (SO2) • Aerosols: ammonium (NH4+), nitrate (NO3-), sulphate (SO42-), chloride (Cl-), sodium (Na+), calcium (Ca2+), Magnesium (Mg2+) The network is operated jointly by Agri-Food and Biosciences Institute (AFBI) and the UK Centre for Ecology & Hydrology (UKCEH), and funded by the Department of Agriculture, Environment and Rural Affairs (DAERA), Northern Ireland. Full details about this dataset can be found at https://doi.org/10.5285/55ad7cf8-fc40-4b8a-9d35-ce970a915ff6

This dataset contains vegetation survey data and nitrate and ammonium concentrations, microbial biomass data, particle size, and nitrification and mineralisation rates within soils from an experiment based at Parsonage Down, UK. The vegetation survey comprises total species percentage cover and species richness data from four 50 cm by 50 cm quadrats. The experiment investigated the effect of different plant groups on soil carbon stores and nutrient cycling, by using a mixture of hand weeding and herbicide spot spraying to create different plant communities on the species rich grassland at Parsonage Down. The resulting carbon and nutrient cycling rates were compared to the characteristics of the plant groups. The experiment ran from 2013 to 2015 and this dataset contains data from 2013 only. This experiment was part of the Wessex BESS project, a six-year (2011-2017) project aimed at understanding how biodiversity underpins the ecosystem functions and services that landscapes provide. Full details about this dataset can be found at https://doi.org/10.5285/4c7c9343-0624-4249-9ab2-183d49d41fe6

We surveyed two salt marshes in each of six estuaries (Solway, Morecambe Bay, Ribble, Humber, Blackwater, Chichester) between September and November 2024 to characterise national differences in denitrification rates and their relationship with potential drivers. A key ecosystem service in coastal systems is the remediation of nutrient pollution through sediment burial, vegetative uptake and microbial processing. Denitrification is a facultative anaerobic process where microbial activity transforms nitrate (NO3-), which in high concentrations can be environmentally harmful, into the environmentally benign dinitrogen gas (N2). Denitrification's magnitude is considered particularly important in saltmarsh systems compared to other habitats, although an intermediate product, nitrous oxide (N2O), can also be given off and contribute to climate change. Full details about this dataset can be found at https://doi.org/10.5285/26efc506-a265-4bb1-8296-d6988ab8d714

We surveyed two seagrass beds and two mudflats in each of six coastal sites in England (Holy Island, Blackwater, Thames, Chichester, Plymouth, Morecambe) between December 2024 and March 2025 to characterise national differences in denitrification rates and their relationship with potential drivers. A key ecosystem service in coastal systems is the remediation of nutrient pollution through sediment burial, vegetative uptake and microbial processing. Denitrification is a facultative anaerobic process where microbial activity transforms nitrate (NO3-), which in high concentrations can be environmentally harmful, into the environmentally benign dinitrogen gas (N2). Denitrification's magnitude is considered particularly important in saltmarsh systems compared to other habitats, although an intermediate product, nitrous oxide (N2O), can also be given off and contribute to climate change. This data accompanies the technical report "Denitrification dynamics and relationships with potential drivers across English saltmarshes, seagrass beds, and mudflats: Capturing national variation in space and time" Full details about this dataset can be found at https://doi.org/10.5285/ea9811f4-5856-4a7e-bbe6-dcea9c115ea2