TERN Ecosystem Surveillance: Soil Pit Sample 

This dataset comprises a comprehensive archive of soil pit samples collected from TERN Ecosystem Surveillance monitoring plots across Australia. Soil is characterised from a 1-meter soil pit located near the southwest corner of each 1-hectare monitoring plot. A soil sample is collected down the soil profile from each recognised horizon, and are collected as part of the soil characterisation process including detailed morphological and profile descriptions. Collected following the standardised Ecosystem Surveillance methodology, the dataset includes over 5,800 soil pit samples archived in the TERN Australia Soil and Herbarium Collection, located at the University of Adelaide's Waite Campus. Each record includes detailed metadata such as voucher barcode for soil collected from each horizon at the soil pit, site and visit information and sampling details. Soil pit samples are accessible and available for loan upon request through the EcoPlots Samples portal via an Expression of Interest. 

We at TERN acknowledge the Traditional Owners and Custodians throughout Australia, New Zealand and all nations. We honour their profound connections to land, water, biodiversity and culture and pay our respects to their Elders past, present and emerging. Datasets funded by TERN include the following statement “This work was jointly funded by the Terrestrial Ecosystem Research Network (TERN), an Australian Government National Collaborative Research Infrastructure Strategy (NCRIS) project. 

TERN Ecosystem Surveillance is a national plot-based field monitoring program that tracks the direction and magnitude of change across Australia’s major biomes. Information on soils and vegetation is collected according to standardised, widely endorsed and consistent protocols across all plots, and includes the collection of soil and vegetation samples and specimens for subsequent analysis. TERN soil pit samples are collected from across the TERN Australia network of 960 monitoring sites nationally, with 410 plot revisits. Large areas of Australia lack sufficient soil information, TERN Ecosystem Surveillance address this gap by collecting standardised soil characterisation information and associated soil samples. Soil pit samples are made available to researchers for future ecological and environmental studies. Soil pit samples enable in-depth characterisation of soil morphology, structure, and stratification, and contribute valuable data to national and international soil information systems. The soil pit samples support the interpretation of soil horizons and physical properties. The archived samples and associated profile descriptions serve as long-term, open-access reference material to support ecological, agricultural, and environmental research across Australia. The samples collected are a once-off snapshot in time. Generally, the quantities allowable for loan are selectable from the following categories (0-10g, 10-20g, 20-60g, 60g-100g). The quantity required for loan will depend on the type of analysis required. The TERN soil pit samples are all archived in the TERN Australia Soil and Herbarium Collection. 

Soil pit samples are collected at intervals down the soil profile (~1m), within horizons at one location in the southwest corner at a plot. Additional supporting data is gathered at the pit and in the TERN lab, including soil classification, bulk density, pH and electrical conductivity (EC). Soil pit samples can be used for physical and chemical analyses. Before storage, samples are oven dried at 40 ^oC for approximately 48 hours, sieved, ground and then stored in sealed containers. Samples are organised by plot location and stored under ambient temperature conditions in the TERN Australia Soil and Herbarium Collection. For each horizon recognised down the soil profile, a sample from each horizon is collected (~500g per horizon). For detailed methods on soil pit sample collection, refer to the AusPlots Rangelands Survey Protocols Manual.