The importance of soils
· Important for long term viability
· Enables larger plant species to colonise the dunes which leads to increased dune stability
· Nature of the soil changes as the dune progresses backwards from the beach.
· Deep sandy soil
· Large soil particles à good drainage
· Water can easily flow through these spaces à transports nutrients
· Dominated by plants that are sand, wind, salt tolerant and low in demand for nutrients
· Humus accumulates as vegetation grows à increases soil’s water holding ability
· Greater the amount of the organic matter in the soil, the longer it takes to dry out
· Therefore, dunes furthest away from the beach (active zone) have the highest organic content, the highest moisture levels and nutrients.
· The amount of organic matter present determines the nutrient levels of the soil.
As a result, vegetation becomes more diverse from the front of the dune system, inland. Therefore, soil types affect the types of plants that can grow in different parts of the dune system. This affects the stability of the dunes and dictates the nature of change that occurs.