The Demonstration Test Catchments (DTC) project is a joint Defra, Environment Agency (EA) and Welsh Assembly Government initiative working in three river catchments – the Wensum in Norfolk plus the Eden (Cumbria) and Avon (Hampshire).
The overall objective of the project is to provide evidence to test the hypothesis that it is possible to cost effectively reduce the impact of agricultural diffuse water pollution on ecological function while maintaining food security through the implementation of multiple on-farm measures across whole river catchments using local expertise to solve local problems. [READ MORE]
What's in the news?
- 14 Nov 2016: Workshop - Innovative ways to improve your farm’s soil, water and profits This free event organised by the Broadland Catchment Partnership attracted 48 attendees from Norfolk, Suffolk, and Cambridgeshire including 26 farmers along with agronomists, other farm advisers and academics. Short presentations from local farmers, agricultural researchers and farm advisers focussed on novel cost-effective techniques and drew on local evidence from the Wensum Demonstration Test Catchment, Morley Agricultural Foundation, Cranfield University and ADAS trials related to cultivations and cover crops. Farmers and advisers had the opportunity to discuss controlled traffic farming, inter-row and tramline management, and the practical benefits and cost savings they can deliver. Attendees were taken by tractor and trailer to see the Estate’s newly installed silt traps for intercepting run-off from roads and a sugar beet pad. For a full account of the event and links to the presentations Click here. (Scroll to the bottom of the page to 'Salle Workshop 2016').
- October 2016: Broadland Catch Up The latest newsletter from the Broadland Catchment Partnership features a lot of the recent work undertaken in the Wensum DTC. Click here to read all about it.
- October 2016: Sedimentary my dear Watson! Three new roadside sediment ponds are being constructed on the Salle Estate to capture soil from damaged road verges, field entrances and areas of concrete hardstanding that is washed down roads during heavy rainfall events and into roadside ditches leading to the river. The ponds are designed to slow the flow of the run-off, allowing sediment to settle in the pond allowing cleaner water to enter the water course. The sediment traps are being funded by the Broadland Catchment Partnerships ‘SlowtheFlow’ project and are due for completion by mid-October. To monitor the effectiveness of the sediment ponds, new high-resolution turbidity probes have been installed upstream and downstream of the site to monitor how the ponds perform during rainfall events.
- October 2016: How will Oilseed Rape compare as a cover crop? Following trials with oilseed radish as a cover crop and different cultivation techniques, all the fields at the Salle Estate that are part of the Wensum DTC study have been sown with oilseed rape. Field drains will be monitored this winter to see how effective oilseed rape is as a winter cover crop compared with oilseed radish at reducing nitrate leaching.
- October 2016: Benefiting from a Biobed A proportion of the pesticides reaching our streams and rivers comes from the preparation and washing of the pesticide spraying equipment. A biobed provides a practical way to deal with pesticide residues that that occur in sprayer handling areas. As part of the work of the Wensum DTC in partnership with the Environment Agency and the Salle Estate, a compost-straw-topsoil biobed was installed which has been shown to reduce total pesticide concentrations in waste machinery washings by over 90%, thus minimising both surface water and groundwater pollution risk. The results of this research has recently been published in the Journal of Environmental Management.
- October 2016: Welcome Maria! Our newest recruit to the Wensum DTC team is Dr. Maria Hernandez-Soriano. An experienced environmental scientist, Maria has recently completed a 3 year post-doctoral fellowship at The University of Queensland (Australia) where she ran projects working on iconic aquatic ecosystems such as the Great Barrier Reef Lagoon.
- October 2016: How to significantly reduce nitrate leaching losses Field trials on the Salle Estate covering 143 ha split into three blocks with differing cultivation techniques and a winter oilseed radish (Raphanus sativus) cover crop, revealed oilseed radish reduced nitrate leaching losses in soil water by 75–97% relative to a fallow block, but had no impact upon phosphorus losses. Average soil nitrate concentrations were reduced by 77% at 60–90 cm depth beneath the cover crop, highlighting the ability of deep rooting oilseed radish to scavenge nutrients from deep within the soil profile. However, employed alone, direct drilling and shallow non-inversion tillage (to <10 cm depth) were ineffective at reducing soil water nitrate and phosphorus concentrations relative to conventional ploughing. Applying starter fertiliser to the cover crop increased radish biomass and nitrogen uptake, but resulted in net accumulation of nitrogen within the soil. In terms of costs, there was negligible difference between the gross margins of non-inversion tillage (£731–758 ha-1) and conventional (£745 ha-1) operations, demonstrating farm productivity can be maintained whilst mitigating diffuse pollution. This work was recently published in the journal Aspects of Applied Biology.
- October 2016: Congratulations Zanist! Who has successfully completed his PhD at UEA. His thesis is titled “Assessment of the application of a cover crop and conservation tillage on soil and water properties and on dissolved nitrous oxide in an arable system” and is based on work undertaken in the Wensum DTC.
To read more about what's been happening see our News page.