Freshwater habitats: Our inland ‘Blue Carbon’ assets

Freshwater habitats: Our inland ‘Blue Carbon’ assets

Freshwater habitats such as wetlands, ponds, and lakes are crucial for carbon sequestration and biodiversity. This blog explores their importance and how they can be managed to provide environmental benefits to communities.

When someone refers to “the lungs of the Earth”, what comes to mind? It’s likely that what comes to mind are forests, and even jungles much further afield than Radnorshire. Of course, the leafy green expanses around the globe are vital for processing carbon and providing us oxygen, and we continue to champion their preservation, recovery and connectivity. However, there’s another precious element that once added to a landscape, creates opportunity for our planet to take ‘breaths’ that help us all out in the race against climate change and biodiversity loss.

So, it is no wonder that within the topic of land management and habitat restoration, some key players get a lot of attention; the inland stretches of squelch such as wetlands, flooded woodlands, the bogs, mires, ponds and lakes. Alongside the Wildlife Trusts, many conservation organisations often advocate for the restoration and expansion of wet habitats. This is not by any means only for goals on biodiversity increase and nature’s recovery.  The win-win of it is that water dominant ecosystems rich in species across taxa can be top powerhouses of sequestering carbon from our atmosphere. You could in fact, name them the true ‘lungs’ of the Earth.

Biodiversity and ‘Blue Carbon’ are our invaluable natural currencies

The array of flora and fauna that wet habitats host is truly outstanding. Whether the habitat is ancient or 6 months old. It’s well known in the conservation sphere that wetlands provide refuge and resources for 40% of all species, with up to 200 new species discovered within them each year (Wildfowl & Wetlands Trust, IUCN, Greenpeace UK). Ponds, according to research by affiliates such as Freshwater Habitats Trust, are often more biodiverse than their larger waterbody counterparts; two in three freshwater species rely on them

Llanbwchllyn Lake, Georgina Hale

Llanbwchllyn Lake, Georgina Hale

Back to ‘blue carbon’. This term was first coined in 2009 to acknowledge and give due recognition to the impressive carbon sequestering capabilities of coastal and marine ecosystems. But what of their inland freshwater habitat counterparts? Working for us in the background, healthy water ecosystems serve us and our overwhelmed atmosphere. Acting as carbon storage, CO2 is removed and fixed into under water sediment, organic matter and aquatic plants, both submerged and surface. Scientists have deemed it long-term storage (thebluecarboninitiative.org), should disturbance and degradation stay minimised.

The true potential of water-dominant landscapes is when a range of minerals, fungi and plants such as mosses are also present. This no doubt brings peatland bogs into the conversation, which cannot be overlooked in the topic of carbon sequestration. The waterlogged, mossy plant matter’s decomposition is slow and doesn’t fully complete, therefore the release of carbon is negligible compared to the amount drawn out of the atmosphere and into the ground. This offset is how a ‘carbon sink’ gets its accolade. Mires, also known as Fens, like at our beloved Pentrosfa, Mynydd Ffoesidoes and Llanbwchllyn Lake, are a type of peatland wetlands fed by sphagnum mosses and sustained by mineral rich groundwater. However, due to human activity, such as extraction from the water table, land drainage to plant crop and trees, plus global warming and draughts, all peatlands are even more precious due to their vulnerability. If water volume is insufficient, peat is extracted for products and habitat is fragmented, the subsequent degradation of peatland rapidly swings the pendulum into carbon emission (UK Centre for Ecology & Hydrology; JH Institute). Thankfully, schemes such as NRW’s National Peat Action Programme (NPAP), help fund the management and of Peatland on Radnorshire Wildlife Trust’s reserves, but this alone cannot tip the balance back.

Pentrosfa Mire, Georgina Hale

Pentrosfa Mire, Georgina Hale

A well-known yet unsung hero, is part of a symbiosis that results in carbon capturing excellence. When a permanent, well-balanced pond or shallow lake is home two high performers: aquatic plants from submerged bed dwellers to floaters such as Duckweed, Water Crowfoot, and the tiny subgroup, Algae (including single-celled Phytoplankton). Aquatic plants’ vital photosynthesis converts carbon dioxide into oxygen and organic matter more efficiently than terrestrial. Their proliferation just needs to be managed. Whereas, although they represent less than 1% of autotrophic biomass, miniscule Phytoplankton contribute to around 50% of the planet’s carbon (C) fixation (Jia et. al 2022; Gilbert et. al 2014) - as well as nitrous oxide (N20).

Creating a mosaic of land with regenerated, expanded and connected aquatic habitats: flood risk is lessened, water storage is maximised and therefore the wider potential of ‘natural capital’ for the people living around them can be realised.

Mid Wales’ network of brooks, streams and rivers that innervate the landscape are our lifeline, a cherished and vital resource for everybody living off this land. The other side to lands being so well-served by water is that when heavy rains come, we are far too often at the mercy of these waterways. Residents are exposed to high risks of flooding, which is ever more prevalent, thanks to climate change. Intervention, nature-based solutions such as creating water habitats (not as counterintuitive as it first sounds) leads to managing flood risk. Paramount for famers and the wider community, encouraging floodplains and pools both ephemeral and lasting, helps mitigate the effects of those erratic seasons that are threatening to make our rivers act the same. The more we can safeguard people against loss of invaluable land and property from the most invasive floods, the more stable life and income can be in to the future. 
 

MidWales Rivers Lakes

[from DataMap Wales] Mid Wales with SSSI (Sites of Special Scientific Interest) and Lake Waterbodies data layers. The rivers – also SSSIs - are highlighted red, clearly highlighting how innervated this land is with flowing water. Lakes are shown in deep blue, main roads in green. Viewing all elements together, shows how the topography of uplands, lowlands, water habitats and human-made infrastructure interact with each other.

So, is wetter always better? The answer usually lies in the delivery, management and strategy. The aim is to slow the flow. Ensuring water is directed and stored with earth staying where it needs to be, both elements doing what they need to do. Keeping soils full of structure and organic matter. Processing more carbon than drier, highly disturbed fields and grasslands that may really have a low species count, with minimal microorganism diversity, leading to low sequestration potential.

This is why scrapes in land for wetland and floodplain formation, pond creation and recognising the potential in ditches and ravines from old glaciers is getting so much talk. Every dip and scar in the landscape can serve as -and often does- the foundation for a habitat where humidity catalyses and supports life, of biological interest and value. Whether land management methods means habitat creation or the revival of ecosystems reliant on water - that have been drained due to climate change and increasing agricultural demands throughout human history.

For people to better experience the benefits of having freshwater habitats around, their preservation and expansion must continue. Whether the financial benefits are acute, such as via green finance, or more subtly developmental due to reducing loss of quality natural capital (land, water, air), rural communities could bring stability into the ever-changing future. Utilising existing landscapes, tweaked to mitigate flood and draught risk, neighbouring with more watery biodiversity hotspots would reveal itself as blue and green carbon potential fulfilled. With healthy and harnessed water, cleansed air and rich soils providing better food for us and livestock, Mid Wales’s is surely a model for richness. Both of health and wealth, from nature-based assets.