00:00This plant might not look like much, but looks are deceiving.
00:06To me, seagrass is an incredible plant, a real superstar.
00:11Seagrass is special, but it's often overlooked.
00:14It's well worth a closer look.
00:18Seagrass protects coasts, shelters thousands of species and stores CO2.
00:23But around the world, these underwater meadows are disappearing.
00:26Since the late 19th century, almost 30% of the world's seagrass meadows have vanished.
00:33What happens when one of our most valuable marine ecosystems disappears?
00:38And can we bring it back?
00:43Conservationists in northern Germany are preparing for an unusual mission – planting seagrass.
00:48It's a major undertaking, but an important one.
00:51Here, on Germany's Baltic coast, seagrass has declined dramatically.
01:00I've been diving for more than 30 years, many of them in the Baltic.
01:04We've seen the changes.
01:06Being able to bring something back to make a real difference, that's what matters most.
01:13The divers carefully lift chutes from a donor meadow, keeping the roots intact.
01:19They take just a few from each spot, so the gaps can quickly close.
01:28Then we bring them underwater and plant them at a suitable spot we've already picked out.
01:36Now the real work begins. One shoot at a time, the divers plant seagrass into the seabed.
01:44Will it become a new meadow? That depends on the conditions.
01:48Sandy sediment, shelter from waves and currents, enough light and enough oxygen in the water.
01:53It's a delicate balance. The young plants need all of these to stand a chance.
02:03Seagrass grows along the coasts of more than 150 countries.
02:08There are around 70 species. Some grow just below the surface, others 60 metres deep or almost 200 feet.
02:16These underwater meadows feed and shelter fish, crabs, shellfish and many other species.
02:22They improve water quality and slow waves, helping protect shores from erosion.
02:30Seagrass has another superpower.
02:33It stores carbon in the seabed.
02:3630 to 50 times faster than forests.
02:40Worldwide, the top 30 centimetres, or about a foot, of sediment beneath seagrass
02:46hold on average almost 90 tonnes of CO2 per hectare.
02:50But how much is stored depends on the species, the site and the sediment.
02:59At Geomar in Kiel, researchers study how seagrass stores carbon in Germany's Baltic waters.
03:08These are samples from the sediment cores we took.
03:13You can also tell there's carbon in here by the smell.
03:16It smells strongly of sulphur, a bit like rotten eggs.
03:27Carbon storage varies from place to place and from species to species.
03:35Some countries have far more seagrass, particularly in the Indo-Pacific.
03:39There, it can play a major role in their carbon balance.
03:44But seagrass' value goes beyond carbon storage.
03:48Its meadows are among the Baltic's most valuable habitats.
03:52They shelter wildlife, stabilise the seabed and help clear the water by trapping particles and nutrients.
04:01Scientists estimate that around 60% of the Baltic coast's seagrass meadows have disappeared.
04:06That's the bad news. The good news is that the decline has stopped.
04:11Less fertiliser now washes from farmland into the Baltic.
04:15But it's still a major problem. Excess nutrients feed algae, which block the light seagrass needs to grow.
04:25So, how do you get people to care about a habitat most never see?
04:31That's the idea behind Snorkeling City.
04:34Daniela Kluge helps children discover what's hidden on their doorstep in the bay near Kiel.
04:39They learn about nature with masks and snorkels, instead of sitting in a classroom.
04:47We hope that once students have seen everything living and growing here in the Baltic for themselves,
04:52especially in the Kiel Fjord, they'll feel more connected to it.
05:03I really enjoyed it. We saw new things I wasn't expecting, and we learned how much life there is underwater.
05:10There's much more than just sand.
05:15For children today, learning about nature really matters.
05:21This generation will have to deal with climate change, water shortages, a lot of challenges.
05:26These problems will be even bigger for them than for us.
05:30We all have to work on them. And you can only protect what you know.
05:38Seagrass is a flowering plant. Its roots hold the sand in place.
05:44So when there's a strong current, lots of wind or a storm, the sand stays here instead of being washed
05:50away.
05:53Seagrass helps protect our coasts from erosion. But how can we restore these natural barriers on a larger scale?
06:01That's what Reinhard Helbig is working on.
06:03The startup co-founder helps restore marine habitats, including seagrass meadows damaged by offshore activity, such as wind farm construction.
06:13His work begins on the beach.
06:19Stormy weather helps us. Waves and currents wash seagrass out of the seabed.
06:24A day or two later, it washes up here, still fresh.
06:30The collected shoots are grown and multiplied in aquaculture. Several months later, the new shoots are laid on a planting
06:37support.
06:39Dried seagrass and a little sediment form a bed to help them take root at sea.
06:49We plant here on land to cut down on underwater work. That means fewer dives and we can do the
06:56painstaking work on shore.
07:00A specially developed machine binds the planted strands with biodegradable thread. The resulting lengths can be laid on the seabed
07:08with less diving work.
07:11Our product is the strand with the plants. We place it under water and together with the aquaculture, that's how
07:18we create a new seagrass meadow.
07:20The goal? Less work by hand and seagrass planted across larger areas.
07:29Our approach helps protect nature and store CO2, all the usual benefits of seagrass. But our planting support can do
07:37more.
07:37It also helps prevent erosion in harbours and along beaches.
07:43It can be used around wind turbines or cables to restore habitats damaged by construction.
07:53Researchers at the Geomar Helmholtz Centre in Kiel are also testing new ways to restore seagrass over larger areas.
08:03One approach starts with seeds.
08:0810% of the plants in our meadows produce seeds. Here you can see them in the seed pouch.
08:16Some are still flowers that will be fertilized. Then the seeds sit in a row like pearls on a string.
08:26The big advantage of restoring meadows from seed is greater genetic diversity.
08:32And in the future we should be able to sow seeds over much larger areas.
08:40Time is short. Warmer waters and other effects of climate change are already putting seagrass under pressure.
08:49Right now we think the most promising way to grow meadows that can withstand climate change is to plant individual
08:55shoots as a foundation,
08:57then sow seeds between them to increase genetic diversity.
09:04But will the method actually work? The answer comes underwater after months or even years.
09:15Today we're visiting the first seagrass meadow planted in Germany's Baltic waters.
09:20It was planted in 2021. We're checking how well it's grown.
09:27The divers count shoots, check how densely they grow and record how the meadow has developed.
09:39Then they compare it with the donor meadow, the healthy meadow that supplied the plants.
09:45Only that comparison reveals whether the new meadow has merely survived or is beginning to function more like a natural
09:51one.
09:54We just checked the seagrass meadow and it's really dense.
09:59We counted lots of shoots per square meter. It's looking good.
10:06Seagrass takes time to recover. Restoring it takes work, patience and money.
10:12But every shoot is an investment in healthier seas, stronger coastal ecosystems and a more resilient future.
10:20But everyone, I can't see as many of us, we've decided the nemesis of a different stream of water.
10:20We don't have to go into any area.
10:22We're trying to push us out as many of us, please.
10:23We're just going to get to the next tier one in the South.
10:23The sooner of the United States has been promoted in a friendly space,
10:24The older of the first was the first of the Pirate Empire, the new one is living in the state.
10:24We in the state of the United States.
