Biochar-mediated reductions in greenhouse gas emissions from soil amended with anaerobic digestates

This investigation examines nitrous oxide (N2O) fluxes from soil with simultaneous amendments of anaerobic digestates and biochar. The main source of anthropogenic emissions of N2O is agriculture and in particular, manure and slurry application to fields. Anaerobic digestates are increasingly used as a fertiliser and interest is growing in their potential as sources of N2O via nitrification and denitrification. Biochar is a stable product of pyrolysis and may affect soil properties such as cation exchange capacity and water holding capacity. Whilst work has been conducted on the effects of biochar amendment on N2O emissions in soils fertilised with mineral fertilisers and raw animal manures, little work to date has focused on the effects of biochar on nitrogen transformations within soil amended with anaerobic digestates. The aim of the current investigation was to quantify the effects of biochar application on ammonification, nitrification and N2O fluxes within soil amended with three anaerobic digestates derived from different feedstocks. A factorial experiment was undertaken in which a sandy loam soil (Dunnington Heath series) was either left untreated, or amended with three different anaerobic digestates and one of three biochar treatments; 0%, 1% or 3%. Nitrous oxide emissions were greatest from soil amended with anaerobic digestate originating from a maize feedstock. Biochar amendment reduced N2O emissions from all treatments, with the greatest effect observed in treatments with maximum emissions. The degree of N2O production and efficacy of biochar amelioration of gas emissions is discussed in context of soil microbial biomass and soil available carbon

Internet delivery of intensive speech and language therapy for children with cerebral palsy: A pilot randomised controlled trial

Objectives: To test the feasibility of recruitment, retention, outcome measures and internet delivery of dysarthria therapy for young people with cerebral palsy in a randomised controlled trial. Design: Mixed methods. Single blind pilot randomised controlled trial, with control offered Skype therapy at end of study. Qualitative study of the acceptability of therapy delivery via Skype. Setting: Nine speech and language therapy departments in northern England recruited participants to the study. Skype therapy was provided in a university setting. Participants: Twenty two children (14 M, 8 F) with dysarthria and cerebral palsy (mean age 8.8 years (SD 3.2)) agreed to take part. Participants were randomised to dysarthria therapy via Skype (n=11) or treatment as usual (n=11). Interventions: Children received either usual speech therapy from their local therapist for six weeks or dysarthria therapy via Skype from a research therapist. Usual therapy sessions varied in frequency, duration and content. Skype dysarthria therapy focussed on breath control and phonation to produce clear speech at a steady rate, and comprised three 40-minute sessions per week for six weeks. Primary and secondary outcome measures: Feasibility and acceptability of the trial design, intervention and outcome measures. Results: Departments recruited two to three participants. All participants agreed to random allocation. None withdrew from the study. Recordings of children’s speech were made at all time points and rated by listeners. Families allocated to Skype dysarthria therapy judged internet delivery of the therapy to be acceptable. All families reported that the study design was acceptable. Treatment integrity checks suggested that the phrases practiced in one therapy exercise should be reduced in length. Conclusions: A delayed treatment design, in which dysarthria therapy is offered at the end of the study to families allocated to treatment as usual, is acceptable. A randomised controlled trial of internet delivered dysarthria therapy is feasible