Defra - Department for Environment, Food and Rural Affairs.

Science Search

Science and Research Projects

Return to Science Search homepage   Return to Project List

N and C mineralisation of soil organic matter and crop residues - NT2101

This project will aim to investigate carbon mineralization rates of harvest residue materials incorporated at different temperatures, validate organic matter mineralization models and review the effect of temperature on microbially- mediated soil nitrogen transformations. The study will be composed of 6 specific objectives outlined as follows, together with ways in which they might be achieved: 1. Measurement of the gross mineralization rate of the harvest residues from 3 different crops (peas, barley, control) at 2 different dates (and hence soil temperatures) by monitoring carbon dioxide efflux; 2. Comparison of the measurement of soil respiration rates by an automated CO2-IRGA system with 2 other methods (hand held IRGA and alkali absorption) at high soil temperature; 3. Validation of organic matter mineralization models. Predicted data generated by the SUNDIAL nitrogen cycle model will be compared with collected experimental data; 4. Assessment of whole datasets from studies NT1504 and NT1513. Datasets will be evaluated in relation to their primary objectives and reported in the most appropriate format for wider dissemination; 5. Production of a review on the effect of temperature on microbially-mediated soil nitrogen transformations. This review will include an executive summary, introduction, evaluation of nitrogen cycle models, literature review and summary; and 6. Generation of a report summarising the results of ADAS mineralization research (1994—1998). Using existing internal reports and published papers, the major findings from each research topic (measurement methods, soil organic matter, arable crop residues, cover crop residues, grassland soils, soluble organic nitrogen) will be drawn together. This review will facilitate incorporation of research findings into practical advice for MAFF and the farming community
Time-Scale and Cost
From: 1998

To: 1999

Cost: £66,545
Contractor / Funded Organisations
Fields of Study
Fertilisers and Nitrate Pollution