Soil Compaction

Many meadows and pastures suffer soil compaction due to the regular passing of heavy machinery and high stocking rates. This can increase run-off during rainfall events and result in the delivery of fine sediments and nutrients to watercourses that can have significant impacts on river ecology. Soil compaction also has impacts on farm yields. If compaction impedes the root stock from penetrating into the soil layers then plant growth, and nutrient uptake, is reduced. This can result in poor crops of silage and hay which are required for feeding stock through the winter months; which is especially important in upland locations where growing seasons are short and winters long.

There are methods to improve conditions where soil compaction has occured. Sub-soil ploughs can penetrate below the compacted layer and break the soil allowing root penetration. This is not always possible in upland regions where soils can be thin with bedrock and boulders close to the surface. Steep slopes can also hinder the use of sub-soil ploughs. Aerators are often a better solution in such locations. These simple rotary blades penetrate into the soil and through the compacted layer allowing greater yields due to oxygen replensihment of the soil and root growth beyond the compacted layer.

If this is carried out in conjunction with newer methods of slurry spreading then yields can be massively improved. Two methods that appear to improve nutrient uptake are dribble bars and slurry injectors. These reduce the liklihood of run-off and allow improved use of a nutrient resource. If carried out alongside aerators and soil testing, for nutrient levels and pH, then savings in time and money can be passed onto the farm enterprise. Often pH levels can be lower then optimal and testing can identify where lime is required. This raises the pH and improves plant nutrient uptake. Soil testing can also idnetify which fields have high levels of phosphates and so allows the farmer to reduce inputs saving them money on fertiliser purchase.

These kind of options, if built into the farm plan, can be beneficial to the farmer and help improve the ecological condition of rivers. Cost of the machinery can be prohibitive but presently there are grants that can help with purchasing the kit. For example Yorkshire Forward's Farm Resource Efficiency Programme grants (FREP: www.yorkshire-forward.com/helping-businesses/rural-businesses/funding/frep) will pay up to 60% of costs. It will even pay up to 50% of costs for the pruchase of one piece of kit for contractors. These grants can make such options feasible for the farmer, either to purchase the kit directly or through their contractors.

Hay time



Soil profiles can help identify if compaction has occurred



Slurry injector





Dribble bar on umbilical

Species found in the dales rivers

Some of the species found in the upland rivers of the Yorkshire Dales.

Brown Trout



Brown Trout Fry



Bullhead





Stone Loach





White Clawed Crayfish





Cased Caddis Fly



Minnows

Fish passes

Many of the Yorkshire rivers have endured an industrial past that reduced their biological diversity. There are stories that during the industrial revolution the Aire was so heavily polluted on its course through Leeds that it's surface could be set on fire. Thankfully recent years has seen a more enlightened attitude and our rivers have see steady improvements, with some unhelpful dips after pollution events. There are still historic headaches that river managers have to tackle. All the Yorkshire rivers are dotted with weirs built to service the old mills. Whilst these have become a part of the aesthetic nature of riverscapes they pose problems for migratory species including lamprey, eels, salmon and trout that have to navigate their way upstream against barrier after barrier that impedes their rout. In low flows the fish can become trapped behind the smaller weirs. In some locations on the Wharfe, such as at Otley, the weirs effectively stop upstream migration of fish and have drastically altered the food webs of the upstream river system.



The Yorkshire Dales Rivers Trust have recently worked in partnership with the Environment Agency to develop a fish pass with photographic recording equipment at Boston Spa, on the river Wharfe. The pass is now up and running and it is hoped it will enable safe upstream migration for salmon, trout, eels and lamprey. The camera equipment will record each fish that navigates the pass to supply important data on fish movement. Ideally we would aim to provide all the significant unnatural barriers with similar passes but the cost is prohibitive so development of fish passes has to be very selective. In the meantime each fish pass is one more battle won to help improve the river ecosystem.