UKCEH Countryside Survey state and change soil data for Great Britain, 1978–2023

Abstract. The UKCEH Countryside Survey (CS) represents the longest ongoing integrated national monitoring program for the countryside of Great Britain (GB), providing policy relevant evidence on environmental condition. Through the use of a co-located sampling design across soils, vegetation, woodlands and waterbodies, the data offer a holistic insight into shifts in environmental condition, the drivers of change and the complex patterns that result across ecosystems, to address a variety of research questions. The soils component of CS is arguably one of the world’s most enduring national-scale datasets on soil health, tracking state and change as part of this broader ‘audit’ of the GB countryside. The monitoring program has been active since 1978, with the latest complete monitoring cycle concluding in 2023 and a new monitoring cycle currently underway (2024–28). The primary aim of this paper is to compile and synthesise all published datasets pertaining to soil state and change, whilst bringing the dataset up to date by reporting on data from the latest cycle (2019–2023). The dataset comprises >8600 topsoil samples from 2,233 plots surveyed over nearly five decades. A comprehensive array of physico-chemical properties are regularly updated with each monitoring cycle, including pH, soil organic matter (SOM), soil organic carbon (SOC, concentration and stock), bulk density, gravimetric moisture content and nutrient loading, though nitrogen content (concentration and stock) and plant-available phosphorus (Olsen P). Nevertheless, numerous additional national baseline metrics have been established throughout the years to address specific policy and research inquiries, including indicators of pollution (heavy metals and organics), biodiversity measures such as invertebrate biodiversity and eDNA based biodiversity estimated for bacteria, fungi and plants, and supporting metrics that facilitate interpretation of soils data, such as texture via laser diffraction particle size analysis, total carbon and CaCO3. Further datasets have been established through specific research queries and use of airdried and frozen soils in the UKCEH soil bank. Contextual data is supplied regarding habitat type, land management practices, and soil type, facilitating wider use of the dataset and subsampling according to need. The datasets have been widely used across over 200 publications and are available under an open government licence, facilitating a unique evaluation of soil state and change over time, within the context of a suit of co-located habitat condition metrics from across Great Britain.