Soils in the UK are finally getting some much needed attention, though funded research, policy changes and the coming together of interested parties who are united in the drive to improve our understanding of this precious resource.
However, there is much still to be learned and indeed policies, regulations and enforcement are not yet up to speed to ensure the survival of high quality soils and our important freshwater fish species such as salmon and trout. The link between soil management and salmon and trout ‘salmonids’ may seem unlikely, but the management of soils directly impacts upon the life cycle of salmonids. Salmonids require clean, oxygenated gravels to spawn, whereas other species of fish such as perch and roach are able to lay eggs on plants or stones that are less impacted by silt (fine soil particles).
For salmonid eggs laid in gravels to survive the winter, they must have water passing through and space around the gravel to breathe. These eggs can become choked or smothered by silt during the winter following soil erosion and run-off. The problem can occur before this stage where no clean gravels are present and initial spawning fails.
These issues are less obvious and chronic than many point pollution events that are often reported, investigated and where appropriate enforced.