Healthy soil is fundamental for healthy ecosystems and creates the foundation of life on earth.
What healthy soil is
When soil is functioning well, it sustains sustain plants, animals and humans as part of a living ecosystem.
Damage to soil structure, compaction, soil chemistry, reduced organic matter and ability to use, filter or retain water means that soil can’t function effectively to grow food, support living organisms such as worms, plant roots and fungi, or store carbon (which helps to reduce carbon emissions).
When a soil has limited air spaces, it becomes waterlogged and loses nitrogen, a process known as denitrification (the loss of nitrogen from the system).
If rainfall moves through the soil too quickly or if it can’t get into the soil because it is compacted or dried out, surface runoff increases, taking soil, nutrients and plant protection products with it, and increasing the risk of flooding.
Healthy soils filter water slowly, retaining nutrients. They help to reduce the effects of extreme weather, such as flooding – an increasing issue for Brighton and Hove as the city increasingly feels the effects of climate change.
Our local soil helps to maintain productivity within food-growing systems across the Living Coast Biosphere Reserve and provide healthier food for people.
A teaspoon of soil can contain more living organisms than there are people living on earth.
It takes 2,000 years for natural processes to make 10cm of fertile soil from bedrock. According to the Nature Conservancy, around 24 billion tons of topsoil are lost every year due to agriculture and erosion.
Creating the conditions for healthy soil is a priority for local strategies such as The City Downland Estate Plan which includes a farm carbon toolkit to monitor local soil health and the Community Composting Network that reduces household waste through providing composting solutions and education to local people.
Brighton & Hove is home to networks of allotments which not only improve health but bring people closer to the soil. Allotments contain soils that store 578 more tonnes of carbon than grassland and support between 4 and 54 times more bees and pollinators than other types of council-managed land. (Brighton & Hove Allotment Federation (BHAF) 2021).
Soils play a vital role in storing and purifying water. The Aquifer Partnership works to conserve and enhance the groundwater stored in the chalk under our feet that provides the Brighton and Lewes area with quality drinking water.
We are working hard to combat the effects of water run-off through sustainable urban drainage.
Soil biodiversity is the range of living organisms within the soil such as earthworms and the roots of plants, which contribute towards its health. Nowhere else in nature are species so densely packed as in soil communities.
Our City Downland Estate Plan Farm Carbon Toolkit uses worm numbers as a key indicator of soil health.
The soils around Brighton and Hove are rich in chalk and support a variety of rare wildflowers, insects and animals that make the South Downs their home.
We are restoring rare chalk grassland and improving habitats on a former golf course at Waterhall through Wilding Waterhall.
Soil as a carbon store
Soil contains microbes including bacteria and fungi and decaying material from once-living organisms such as plants and animals. The organic matter in soil is high in carbon. The ability of soil to store carbon helps to reduce emissions in the atmosphere that contribute to climate change.
Soil carbon comes from the growth and death of plant roots, as well as the transfer of carbon-enriched compounds from roots to soil microbes.
Maintaining healthy soil systems directly reduces the impacts of climate change. Soil carbon storage is a priority for The Brighton & Hove Carbon Neutral 2030 Programme which found that 16 kilotonnes of greenhouse gases came from nature, agriculture and land use – around 1% of all greenhouse gases from the city of Brighton & Hove in 2018.
Through the programme we are working to enhance natural areas in and around the city to restore the ecosystems that store carbon within plants and soils.