These data consist of stream water chemistry for selected Welsh upland rivers. The sampling sites were located in sixty one small and medium catchments. Catchments were chosen from the Welsh Acid Water Surveys (WAWS) program (41 sites) and the Wye catchment (20 sites). Results for pH, alkalinity, conductivity and major cation and anion measurements are presented for the WAWS catchments. Results for pH, alkalinity, conductivity and major anion measurements are presented for the Wye catchment. Samples from the Wye catchment were collected in May 2012. Samples from the WAWS catchments were taken during the summer and autumn of 2012 and spring and summer of 2013. The data were collected to characterise water chemistry variation along a gradient of aquatic biodiversity associated with different environmental settings for example land-use intensify and recovery from acidification. Dr Isabelle Durance was responsible for organising the surveys, Dr Hugh Feeley was in charge of collecting and preserving the water samples. Analysis of the water samples was carried out at the Forest Research Laboratories. The work was carried out under Diversity in Upland Rivers for Ecosystem Service Sustainability (DURESS) project (Grant reference NERC NE/J014818/1). DURESS was a project funded by the Natural Environment Research Council (NERC) Biodiversity and Ecosystem Service Sustainability (BESS) programme. Full details about this dataset can be found at https://doi.org/10.5285/d329ca18-c3d8-49f0-b2fd-5243d76dc650

This dataset consists of fish species, fish length and fish weight from samples taken from small and medium catchments across Wales. Samples were collected in the summers and autumns of 2012 and 2013 using electrofishing. All the collected individuals were counted and recorded to represent the fish diversity and abundance of each sampling site and date. The main goal of this survey was to relate fish production with a gradient of aquatic biodiversity associated with different environmental settings (land-use intensify, recovery from acidification). Dr Isabelle Durance was responsible for organising the surveys, Dr Hugh Feeley was in charge of collecting, sorting and measuring the fish samples. The work was carried out under the Diversity in Upland Rivers for Ecosystem Service Sustainability (DURESS) project (Grant reference NERC NE/J014818/1). DURESS was a project funded by the Natural Environment Research Council (NERC) Biodiversity and Ecosystem Service Sustainability (BESS) programme. Full details about this dataset can be found at https://doi.org/10.5285/57f95ff8-e1b0-41b9-866a-feb231aecb67

These data are for macroinvertebrate taxonomy and abundance of Welsh upland rivers. The sampling sites were located in small and medium catchments across Wales. Sampling took place in either spring 2013 for sites in the Wye catchment or during 2012 for the other catchments. At each sampling point, 2-minute kick-samples were taken from river riffles to represent macroinvertebrate composition. Samples were preserved in industrial methylated spirit on site. Samples were then sorted and identified in the laboratory. The main goal of this survey was to characterise a gradient of aquatic biodiversity associated with different environmental settings for example land-use intensify and recovery from acidification. Dr Isabelle Durance was the responsible of organising the surveys, Dr Hugh Feeley was in charge of collecting, processing and sorting the invertebrate samples. Kath Layer was commissioned by Cardiff University for the identification. The work was carried out under Diversity in Upland Rivers for Ecosystem Service Sustainability (DURESS) project (Grant reference NERC NE/J014818/1). DURESS was a project funded by the Natural Environment Research Council (NERC) Biodiversity and Ecosystem Service Sustainability (BESS) programme. Full details about this dataset can be found at https://doi.org/10.5285/8f7b2269-73b1-449f-8590-e36c7c850913