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The contribution of cover crops incorporated in different years to nitrogen mineralisation - NT1526

Description
To reduce nitrate pollution of drinking water, cover crops are used to immobilise nitrogen over winter. However, no account is taken of nitrogen that is immobilised by cover crops and subsequently remineralized, as there is only limited data on the subject. This project will aim to provide such information by extending an existing experiment (at ADAS Gleadthorpe and ADAS Terrington) which is already investigating mineralization of cover crops that have been incorporated in 3 separate years. In a proposed fourth year, cover crops will be grown on an area different to that used for incorporation. Assessments will be made of: soil mineral nitrogen to 90 cm at incorporation and following crop harvest; potential mineralizable nitrogen to 30 cm at incorporation and following crop harvest; dry weight of grain and straw of the following test crop; and nitrate leaching in the winter after harvest of the following test crop. Mineralization of a single cover crop material will be measured in the season following incorporation up to harvests of the following crop. The contribution of cover crops incorporated in each of 4 consecutive years to mineralization following the fourth year up to harvest of the following crop will be estimated. Cover crop mineralization will be interpreted in terms of the carbon: nitrogen ratio of the cover crop, environmental variables and soil properties.
Project Documents
• Final Report : The contribution of cover crops incorporated in different years to nitrogen mineralisation   (668k)
Time-Scale and Cost
From: 1998

To: 1999

Cost: £60,052
Contractor / Funded Organisations
ADAS UK Ltd.
Keywords
              
Fields of Study
Fertilisers and Nitrate Pollution