Blog 8 - All you need for healthy beaches & dunes: the 3Ss
SAND, SPACE and SPECIES
(No! not sun, sand and sea, we’ll get to that later)
Even though we all love our trips to the beach, we seldom give a second thought to how the beach is feeling (stick with me this is going somewhere!). Until that is, we can clearly see the beach or dunes are in a bad state, stressed and battered by winter storms maybe, or just looking a bit dishevelled and in need of some care. While they may not have feelings we can certainly think of them in the sense of being healthy or in bad health. As coastal scientists we try to better understand how they work: what are the factors that support healthy growth, or the causes of deterioration over time.
I can now reveal – for the first time – that +100 years of this science can be boiled down to just 3 words, the 3Ss: Sand, Space and Species.
The key though is that the health of the beach & dunes is the focus here, and we are not (that’s a tough one because it goes against our mindset for the last 80 years on this little planet). We do however reap huge rewards froutting the beaches and dunes 1st.
SAND
Ok, this is the easy one. We need sand. Beaches can actually make do with larger particles of sediment (like pebbles and cobbles), but dunes are made by wind and so usually need the smaller particles that are sand-sized. Sand comes and goes though, and that is where we need to be aware of anything that may hinder or cut off that supply.
For example dammed rivers can no longer supply sediment to the coast to replenish beaches; seawalls and promenades are often built directly on top of dunes, those sands are no longer there to feed the beach; marinas and harbours can stop the flow of sands along the coast – see an example in this image.
If you are ever talking to “the experts”, don’t let them bamboozle you with jargon and fancy analyses. Keep asking the same question until you get a straight answer:
“Do we have enough sand to maintain the beach and dune in the long-term?”
SPACE
A vital part of climate change solutions that can last for decades is the idea that we should be ‘working with natural processes’, not trying to stop them (beach-dunes as coastal protection link). Continual coastal development gobbles up our coastal dunes on the landward side, while sea-level rise is causing beach and dune loss at the seaward side. This ‘coastal squeeze’ is a serious threat to our natural coastal heritage. There is a need to allow space and time for nature to function, but also to manage these resources to allow for our multiple shared uses, like sunbathing, fishing, sandcastle building, horse-riding, dog-walking, beach volleyball, nature walks, surfing (the list is endless). If planned properly there is no reason that healthy systems cannot support nature and allow our more practical and recreational needs, while at the same time recover naturally from storm events.
The question for the “experts”:
“Have we left enough space for sand to move by wind and waves?“
SPECIES
Healthy beach-dunes have both physical and living components. The physical part is made up of the shapes the sands make, flat beaches, gently or steeply sloping, little hills of sand, ripples, beach or dune ridges, large hills tens of metres high with deep hollows. This diversity of shapes results in a variety of wind speeds, temperature, saltiness, shading and freshwater levels. And so has a big part to play in what plants and animals can survive there.
They need to be pretty specialised to adapt to this harsh environment, and often this means they are highly valued for conservation (nearly all of Ireland’s dunes are designated as Special Areas of Conservation). One particular trait of many of the plants is their long roots. These root networks are great at binding the sand in place giving the dunes stability and robustness against erosion.
Although tough, dune plants are also quite fragile. They cannot take very much trampling from our activities: walking, camping, running, picnicking. While some of our past-times destroy them directly – for example campfires or quad-biking. As we damage the plant cover, it dies off and sand is no longer held in place – free to blow away on the wind. In this way we lose the dunes ability to protect us from coastal storms, we lose the biodiversity and habitat value (in some cases small disturbances are good, but …), we lose the beauty and visual richness so valued by tourism, we lose so many things we take for granted, but get for free (some examples here: https://www.youtube.com/watch?v=PgtkM7wim9Q). [Dune plants image from www.field-studies-council]
The question for the “experts”:
“Are we giving plants and animals time and space to survive?”
Don't be intimidated
Beaches and dunes are complex places. They become more complicated when we factor in the demands we place on them. And on top of that we need to consider the wickedness of climate change. But don’t feel overwhelmed by it all, just remember it’s really pretty simple. We just need to keep returning to three themes – the 3Ss: Sand, Space and Species.
Activity
It also works great as a chant, as you march the kids down to the beach on a summer’s day
What do we need? SAND
What do we need? SPACE
What do we need? SPECIES
What do we need? SAND SPACE SPECIES,
SAND SPACE SPECIES,
SAND SPACE SPECIES ...
(Repeated until they reach their destination!)
In the coming months I’ll expand on these three themes, with a blog post dedicated to each one.
Hijacking the 3Ss
You may know of the 3Ss already as sun, sand and sea. That sales motto for Mediterranean holidays has been a death-knell for our beautiful beaches and dunes, because every attempt is made to eradicate the living, messy, annoying parts of these environments – the plants (labelled weeds) and animals (labelled pests), to the point where they become sterile and useful only for our needs. While it is not necessarily a motto that is used for non-Mediterranean beaches its essence has most certainly spread world-wide. We desperately need to push back against this mindset and begin to work with nature. The new 3Ss is a step in that direction.
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