Powerpoint exploring the locations used in television show Time Clash
Muddy Floods And Compacted Soils – Current And Future
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2. Muddy floods and compacted soils – current and future Paul Sadler Planning and Corporate Services Manager for SW Observatory Land and Food seminar 8 December 2009
6. Compaction - inevitable with high risk crops - inevitable with long periods of wet weather
7. What causes muddy floods? Intense rainfall Compacted soil Extremely intense rainfall Any exposed surface of vulnerable soil type Sufficient slope Sufficient slope Muddy flood
8. What causes compaction and runoff? Machinery Livestock Compacted soil Particularly when soil is wet Rain impact Capped soils (sand/silt soils) Runoff
9. In future what factors might change? Machinery Livestock Compacted soil Particularly when soil is wet More frequent and intense rainfall Crop cover Runoff
17. The role of the Environment Agency Prosecution as a last resort
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Editor's Notes
Pictures taken near Kentisbeare on sandy soils
Picture shows sandy soils vulnerable to soil erosion and runoff. Sandy soils significant in Devon, ridge of sandstone Otter and up into Wellington Somerset and Quantocks, sandy soils-notorious for muddy floods and their effects; freely draining in groundwater so no water courses so ends up on roads…. Capping problem in particular=unstable sand, when it rains battering disperses the sand so it blocks the pores then makes the soil impermeable, any bare sandy soil or soil with high sand content prone to capping; a crust forms across it, can reduce inflitration to 1mm hour (equivalent to drizzle); main way of dealing with it is to anchor the soil with a crop early planting winter cereals, it’s not the crop it’s the drilling late in November crop doesn’t come up soon enough so soil exposed to capping effect
Capping and also compacted layer at depth caused by livestock or machinery when wet
East Devon problem area – surveyed as high risk, others high risk unsurveyed Floods – feniton and ottery looked at every field, then where problem subsoiler, every field treated
Survey goes with the map – soil surveyor, looked at soils in winter, methodologoy for looking at soil condition, severe = erosion (gullies), high = runoff evidence, moderate – might be capped but not causing runoff, MP=mod poor= some evidence of runoff therefore need to do something, low=fine 50% in SW degraded, with wetter winters even worse; Richard Smith 01392352293
1 st picture is subsoiler working maize stubble
2 nd picture is subsoiled land also planted with mustard cover crop to reduce risk of capping Picture also shows edge of field that is not subsoiled showing runoff
Picture shows how crop cover reduce runoff. Lack of crop cover on the left…..cereal crop planted early in the autumn with no runoff, kentisebeare Lack of early maize access and potatoes too – variety’s ; if seed bed left knobbly – when