Seagrass Restoration for a Healthier Planet

 Coastal erosion is accelerating worldwide due to climate change and human activity, threatening homes, habitats, and coastal communities. Seagrass meadows play a vital protective role by stabilising sediment, reducing erosion, slowing wave energy, capturing carbon, and improving water quality. With global seagrass in steep decline, large‑scale restoration efforts, such as those led by Swansea University, UK, are essential to protect coastlines and support planetary health.

                                                   Image by Dr David Buss created using OpenAI

The impact of coastal erosion

Given that nearly 70% of the Earth’s surface is covered by the sea, coastal erosion (the weathering and loss of coastal land, beaches,marshes, rocks, or cliffs caused by waves and tides) has become a serious problem in many parts of the world. Coastal erosion can lead to the loss of homes, natural habitats, infrastructure, and community livelihoods, resulting in huge economic costs and, tragically, sometimes loss of life.

Having been born in an area with a long coastline and now living on an island, I am well aware of its impact. I have witnessed beaches shrink over time and coastal communities become fragmented.

Climate change and human activities play a crucial role in accelerating coastal erosion. Sea levels are rising due to warming oceans and melting ice sheets. Even small increases in temperature can reshape coastlines. Scientists are now recognising that seagrasses could play an important role in preventing erosion.

Seagrass and its impact

Seagrasses are the only flowering plants that grow in marine environments. Several species exist, many with long, narrow leaves resembling land grasses. Their underground roots spread across the seabed, forming extensive underwater meadows that provide habitat for diverse marine wildlife and, during low tide, non‑marine species such as birds. Seagrasses are among the most widespread marine ecosystems on Earth, covering around 300,000 km² of seabed across 159 countries.

Research indicates that seagrass can act as a critical natural defence against coastal erosion. Their root mats trap and anchor sediment, reducing shoreline erosion by up to 70%. Seagrass meadows also slow wave energy, effectively acting as a buffer during storms.

In addition, seagrasses capture carbon from the atmosphere, reportedly up to 35 times faster than tropical rainforests, and absorb pollutants, improving water quality. Overall, they play a vital role in maintaining planetary health. In recognition of this, the United Nations has designated 1March as World Seagrass Day.

Decline of Seagrass

Despite their importance, global seagrass coverage is declining due to human activities such as rampant coastal development, pollution, climate change, dredging, and damage from boat propellers. The UK has lost approximately 90% of its seagrass meadows, with half of that loss occurring in the last 30 years. Seagrasses in the USA are also experiencing extraordinary decline, with losses of over 90% recorded in Florida’s Big Bend.

Seagrass restoration in the UK

Reversing this decline requires active conservation: protecting remaining meadows and restoring those that have been lost. One notable initiative is led by researchers at Swansea University, under Dr Richard Unsworth. They are developing methods to restore seagrass meadows at scale.

With the planting of 2‑hectare meadows, the team is undertaking one of the UK’s largest seagrass restoration projects. They are now involved in restoration efforts in North Wales, the Solent, and the Firth of Forth in Scotland. Working with research partners, they are developing scalable restoration techniques that could help reverse the decline of this endangered ecosystem on which the health of our planet depends.

 

References: 

The UK's biggest seagrass restoration project - Swansea University

Extensive and Continuing Loss of Seagrasses in Florida's Big Bend (USA) - PubMed

Phthalate exposure alters heart muscle cell behaviour and could lead to heart disease

Phthalates, as plasticisers, are ubiquitous in the environment, found in everyday objects such as cosmetics, packaging, pharmaceutical pills, children’s toys, shampoos, detergents etc. In fact, phthalates are so pervasive that measurable levels of many metabolites are found in the urine of the general American population.

Phthalates are easily leached into the environment due to its structure; the process  is hastened as plastics age and breakdown. Exposure of humans occurs largely through diet and through contact with phthalate containing materials.

Phthalate exposures in laboratory animals have been show to affect the reproductive system leading to disruptions of hormones and could be endocrine disruptors. Phthalates have also been linked to behavioral disorders in children.  Previously in our blog, we discussed how phthalate exposure in expectant mothers could lead to aggression, conduct problems, attention problems, and depression in children. Now a new study by scientists from George Washington University, USA, explored the effect of a phthalate Diethylhexyl phthalate (DEHP)  on cardiomyocytes (cells that comprise the heart muscles). DEHP is found in a range of products such as  building materials, medical devices, paints and adhesives and also found in food products due to leaching during food production and storage. The researchers found that  Di(2-ethylhexyl)phthalate (DEHP ) can cause changes in metabolic processes in the cardiomyocytes by increasing the genes that are involved in the transport of fatty acids, oxygen consumption etc.

 So what are the implications of this finding?  Dependence of the cardiomyocytes to fatty acids for energy production could lead to an abundance of lipid intermediates and reactive oxygen species. Phthalate induced change in the heart muscle cells could lead the heart  to be sensitive to injury caused by reduced oxygen and also cause dysfunction of ventricles which could lead to a range of heart diseases resulting in heart failure. 

References:

Posnack NG, Swift LM, Kay MW, Lee NH, & Sarvazyan N (2012). Phthalate Exposure Changes the Metabolic Profile of Cardiac Muscle Cells. Environmental health perspectives PMID: 22672789

Global Forest Resources Assessment 2010

The Food and Agriculture Organisation’s Global Forest Resources Assessment 2010, which surveyed 233 countries, stated yesterday (25th March)that the global rate of deforestation has slowed down over the past decade, from 16 million hectares per annum in the 1990s to 13 million hectares per annum in the 2000s. Natural forest progression and afforestation programmes (mostly in China, India, Vietnam, and the US) have resulted in an addition of more hectares of new forests per annum (Asia had a net gain of 2.2 million ha per annum in the 2000s). Two countries which had the highest deforestation rates in the 1990s, Brazil and Indonesia, have significantly reduced this in the 2000s: from 2.9 million ha p.a to 2.6 million ha p.a in Brazil and from 1.9 million ha to .5 million ha in Indonesia). North and Central America had stable rates, whilst Europe had a slower rate of forest expansion than before. Yet, forested areas around the size of Costa Rica is being destroyed each year, mainly due to clearing lands for agriculture and natural causes. The highest net annual forests loss were in South America (4 million ha) and Africa (3.4 million ha). Primary forests (36% of total forested area) have decreased by more than 40 million ha since 2000. I have referred to some aspects of deforestation in Our Gossamer Planet, but I would like to point out the one great benefit of the forests (currently over four billion hectares)- they act as carbon sinks- absorbing and storing greenhouse gases. There’s more in ‘Biodiversity in India’ in The Ship 09/10, published by St Anne's College, Oxford. The Assessment’s findings are seminal, with 2010 being the UN-designated International Year of Biodiversity. Yet, the aim should be to reduce global annual deforestation rates to the proportions of a school’s playground, or perhaps even less!