Ash-free dry mass (AFDM) of three distinct size fractions of organic matter (>1cm, >1mm and > 0.025mm) collected in quantitative samples of the benthic substrate determined from up to 10 replicate samples at three chalkstream sites in the Wessex chalk area (Nine Mile River, River Till and River Wylye) on each sampling occasion. Data were collected on seven occasions on the Wylye and Nine Mile River and on five occasions on the Till, between October 2012 and October 2013. Data were collected to construct quantified food webs detailing the flux of mass and nutrients between nodes of the food web. This dataset was created as part of work package 3.2 of the Wessex Biodiversity & Ecosystem Service Sustainability (BESS) project.
You must cite: Duerdoth, C.; Arnold, A.; Pretty, J.; Murphy, J.; Hawczak, A.; Jones, J.I. (2017). Benthic organic matter biomass data for three intensively studied Wessex chalkstream sites, England, UK. NERC Environmental Information Data Centre. https://doi.org/10.5285/0446bf29-8f7e-4132-9b34-1b66b9ff5b78
Samples were collected on 7 separate occasions from Nine Mile River and the River Wyle. However samples were only collected on five occasions from the River Till. No sampling occurred in this river during the salmonid breeding season Dec-Mar so as not to disturb redds. Ten replicate samples have been processed from Oct 12, Feb 13, Mar 13 and May 13 sampling. Five replicate samples have been processed from Jul 13, Aug 13 and Oct 13 sampling.
Standard laboratory procedures for determining AFDM content were followed but there was no formal quality assurance procedure, such as repeat analysis of replicate samples from within a replicate Surber sample. Final values were checked for marked outliers (none were found) before calculations were undertaken.