Tag: Seagrass

Counting on … day 203

12th December 2025

Can the acidification of the oceans be reversed? This from Biology Insights

“Reversing ocean acidification involves both natural and engineered approaches. The Earth has self-regulating mechanisms, such as the dissolution of calcium carbonate sediments on the ocean floor and the weathering of rocks on land. These processes release alkaline materials that neutralise acidity, but they operate over thousands of years and are too slow to counteract the current rapid changes.

“Scientists are exploring geoengineering techniques to accelerate this process. One proposal is ocean alkalinity enhancement, which adds alkaline substances like ground olivine or lime to seawater to increase its pH. This method seeks to speed up the natural weathering process to neutralise excess acidity.

“Other methods are more technologically intensive, such as electrochemical approaches that remove acidity directly from seawater. These systems would use electricity to manage ions and reduce acidity, but they face challenges of scale, cost, and energy requirements. The potential for unintended ecological side effects from these engineered solutions is not yet fully understood.” (1)

It is hard to imagine how either the geo engineering or the electrochemical solutions can work at scale. Ditto for proposals that carbon dioxide could be removed from the oceans and stored underground using carbon capture technology.

More promising are projects that focus on planting seaweeds such as kelp and sea grass which as they grow absorb carbon dioxide from the water. (2) At the same time such projects improve marine biodiversity, and indeed are often established as part of Marine Protected Areas. These project are often simply restoring ecosystems that have been degraded by human exploitation. Nevertheless even plants such as seagrass can struggle as temperatures rise and as ecosystems become more unstable. (3) 

Therefore the most important way of protecting our oceans is to to reduce significantly and at speed the amount of carbon dioxide that we emit.

  1. https://biologyinsights.com/is-ocean-acidification-reversible-a-scientific-look/
  2. https://www.mbari.org/news/seagrasses-turn-back-the-clock-on-ocean-acidification/

(3) https://www.mccip.org.uk/sites/default/files/2021-07/mccip-seagrass.pdf

Windows of Opportunity 

8th December 2023

Planting what grows best

Trees, peat bogs, and seaweed forests all absorb and store carbon. Trees provide shade from the sun and protection from the wind and heavy rain. Trees and peat bogs slow the flow of water and prevent flooding. Seaweed forests and mangroves protect the sea bed and vulnerable shore lines. Cutting down trees and clearing forests, and draining bogs and wetlands released carbon and exposes the land to degradation. 

“The Committee on Climate Change (CCC) …advice on the sixth bin budget , covering 2033-2037, estimates that woodland cover in the UK would increase to 17% by 2050 if the Government meets its target of planting 30,000 hectares of trees annually from 2025. The Committee suggest it would be feasible to increase planting to 30,000 – 70,000 hectares of trees from 2035, leading to an increased woodland cover of up to 20%” (1) Woodland cover is currently around 13%.

The Wetlands and Wildlife Trust aims “to bring back some of these vital habitats, calling for the creation and restoration of 100,000 hectares of healthy, well-managed wetlands across the nation.” (2)

“A study earlier this year [2021] concluded that 92% of the UK’s seagrass has been lost in the past two centuries, with 39% disappearing just since the 1980s, thanks to pollution from industry, mining and farming, along with dredging, bottom trawling and coastal development…. A consortium, including Project Seagrass, WWF and Swansea University, has planting more than 750,000 seagrass seeds in Dale Bay in Pembrokeshire, with the aim of eventually restoring 3,000 hectares (12 sq miles) of meadows in the UK by 2030. That area of seagrass could suck up the emissions of 3,000 small cars, create a habitat for billions of small animals, support 4,700 more fish than bare sediment, and increase sediment strength tenfold to prevent erosion.” (3)

(1) https://researchbriefings.files.parliament.uk/documents/CBP-9084/CBP-9084.pdf

(2) ) https://www.wwt.org.uk/news-and-stories/news/the-state-of-global-wetlands-in-2021-new-report

(3) https://www.swansea.ac.uk/press-office/news-events/news/2020/03/750000-seeds-planted-in-wales-inuks-biggest-seagrassrestoration-scheme-.php