Apart from coastal bathers who’ve gingerly waded through its tickling stems or sailors who snared their anchors in its undergrowth, few of us are aware of the 60-plus species of marine flowering plants that constitute seagrass. Fewer of us still appreciate that, like their submarine cousin coral, seagrass orchards are under threat. “The problem with seagrass is that it’s not a charismatic habitat like your coral reef or tropical mangrove,” says Project Seagrass’ Leanne Cullen-Unsworth of the family marine plants that grow in shallow and sheltered coastal waters across the globe.

Seagrass provides a range of services to terrestrial ecosystems: food and habitat for marine organisms, maintaining water quality and stabilising the seabed. Most importantly, seagrass meadows are the hidden stars of carbon sequestration; absorbing atmospheric carbon at quicker and higher rates than ecosystems such as tropical forests, one hectare of seagrass can store around 400 kg of carbon dioxide per year, up to 40 times more than a hectare of dry-land forest. (Making it second only to arctic tundra in its capacity as a carbon sink.)

Partly this is down to seagrass’ marine habitat, where oxygen-free sediment traps the carbon in plant material which then remains buried for hundreds of years after the plant dies (unlike the carbon in forests, which can readily be released by burning for fuel).

So seagrass’ loss is a problem for all of us. And sadly, in most global contexts these hard-working marine flora are receding. It is estimated that 92 percent of seagrass in British coasts has been lost in the last century, much of this erosion having occurred by the mid 20th century, when poor water quality borne of rapid industrialisation led to a wasting disease that scientists believe decimated seagrass meadows. Sediments and turbidity have also played their part in seagrass’ demise, as has physical damage from anchors and fishing nets, commercial seaweed production and the tourist industry, where aesthetics of pristine sands and transparent seas reign supreme.

“In tourist spots in the Indo-Pacific it’s common for seagrass to be torn up so a beach looks like the picture postcards,” Cullen-Unsworth says, who is however at pains to point out that seagrass conservation is not simply pitted against human activity – it provides a nursery habitat for commercial fish stocks such as tiger prawn, conch, Atlantic cod and white-spotted spinefoot. Cullen-Unsworth is one of the founders of Project Seagrass, a nonprofit that’s working to raise awareness of this underrated habitat and is undertaking pilot projects to explore how to best regrow eroded seagrass orchards.

Project Seagrass’ first large-scale project, Seagrass Ocean Rescue, is a partnership between Project Seagrass, Cardiff and Swansea universities and Pembrokeshire Coastal forum that aims to reestablish 20,000 square metre seagrass meadow in Dale, West Wales to demonstrate its environmental and biodiversity benefits, and serve as a model that could be replicated anywhere in the world where seagrass meadows are under threat. Costing GB£40,000 [US$52,000], the project is funded by charitable donations and the first of three ocean sites in Wales and England where Project Seagrass plan to restore native seagrasses in coming years.

The project involved volunteer divers harvesting two million donor wild seagrass seeds from extant meadows around the coast of the United Kingdom. The seeds were then planted in biodegradable hessian bags, by volunteers including Welsh schoolchildren, and these bags were launched into the sea at ideal sites off the Pembrokeshire coast. The chief limitation of the project is that native seagrasses take years to reach maturity, making data-gathering on best methods for replanting a slow process. The final seed bags were deployed in December 2020, says Cullen-Unsworth and though it’s early days she’s hopeful.

“We’re already seeing signs of germination,” she says. “It might be five to 10 years before we can absolutely demonstrate evidence of benefits in terms of carbon sequestration and biodiversity support, but still it’s all very exciting.”

Seagrass Ocean Rescue is one of a handful of global projects seeking to reseed lost seagrass meadows, including a 20-year project to restore native eelgrass meadows at Chesapeake Bay in the US and a University of Gothenburg-led project to restore seagrass meadows along Sweden’s West Coast. Cullen-Unsworth believes that this underwater climate hero will soon get the attention it deserves.

“Britons used to be maritime people who were fully aware of marine habits like seagrass and their role in helping ecosystems to thrive. My hope is that seagrass will once again be as appreciated as grasslands and forests.”

Author: Sally Howard, The India Story Agency for Sacred Groves

The post Saving a Sub-Marine Climate Star appeared first on The Sacred Groves.

Under the azure waters of the Andaman Sea, sturgeon, parrot fish and stingrays swim past a strange new structure close to a coral reef formation. Above, a small solar panel bobs on the water’s surface. This is an artificial reef built by Indian environmental charity ReefWatch. The founders of this tiny non-profit outfit are passionate about the conservation of the magnificent coral atolls in India’s Andaman and Nicobar Islands, training local divers to collect naturally broken coral fragments and implant them on to an artificial metal reef. There is, they soon realised, one basic problem with building new coral reefs: “Coral reefs grow between 0.5-7 cm per year,” says Nayantara Jain, Executive Director of the programme. “At this rate, it will take artificial reefs decades to flourish.”

So ReefWatch implemented a simple, radical strategy to enable coral to grow faster. “We hook our artificial metal reefs to a small floating solar panel,” explains Jain. The mild electric current generated by the floating solar panel helps speed up coral growth by seven to twelve times by enabling faster accretion of calcium carbonate. And the electric current leaves the coral with more of an energy budget that it can use to survive warmer temperature spells and coral disease. Jain and her small team, which includes three local youth, predict these artificial reefs could have a far-reaching impact. Just before the lockdown, the team developed a new solar panel design to make coral accretion even more efficient. With the old accretion system, coral would start re-growing within three months. “Now, perhaps it will grow faster,” Jain says. The team also creates diverse natural habitats under each artificial reef using rocks, shells and aquatic plants. “Consequently, we see an immediate uptick in marine life as soon as the artificial reef is set up,” she says.

In the long term, ReefWatch plans to develop a replicable model for coral reef regeneration which involves local stakeholders. Some of their work involves education: through workshops in schools, colleges and elsewhere, they are spreading awareness about how coral reefs protect the fragile local ecology and bulwark these islands against tsunamis and high tides. “We’re also employing local divers to salvage broken coral and maintain our new reefs,” she says. “Hopefully, this will encourage them and others in their community to look after their habitat.” Jain plans to make the project volunteer tourism-driven and hopes to entice divers and beach enthusiasts to spend some time in these picturesque islands and help build artificial reefs. “If protecting their biodiversity could generate higher tourism revenues,” she says, “the programme could eventually be taken over by the local community entirely, leaving us free to replicate this project elsewhere.”  

ReefWatch has built nine reefs so far, all positioned near natural coral formations. In time, these will mature, merge and support diversity of marine life. Each reef costs around US$2,000 and requires regular maintenance in the first few years of its installation. On World Oceans Day in June 2020, ReefWatch launched the first edition of its Adopt A Reef programme, inviting people to sponsor part of an artificial reef for US$470 per year. Within six weeks, all their existing reefs found sponsors. “The government has now allowed us to work in other areas in the Andaman Islands,” says Jain. “We want to build more reefs now…”

Images Credit: ReefWatch Marine Conservation
Author: Geetanjali Krishna, The India Story Agency for Sacred Groves

The post Recreating Rainforests of the Deep, One Reef at a Time appeared first on The Sacred Groves.