Seagrass Meadows Key to Climate Change Mitigation

Len McKenzie

May 01, 2016

Len McKenzie
Principal Researcher & Program Leader, Seagrass-Watch
Secretary, World Seagrass Association
Dugong & Seagrass Conservation Project Technical Advisor

Len has over 20 years’ experience as a research scientist on seagrass ecology, assessment and fisheries habitats. He leads the global seagrass research and monitoring program Seagrass-Watch, is the Secretary of the World Seagrass Association, program leader for the Inshore Seagrass component of the Great Barrier Reef Marine Monitoring Programme, and leader of a series of projects assessing the condition, trend and risk in coastal seagrass habitats. Len is based at the Centre for Tropical Water & Aquatic Ecosystem Research (TropWATER) at James Cook University in Cairns, Australia and is a technical advisor to the Dugong and Seagrass Conservation Project.

What’s the difference between seagrasses and algae?
Unlike algae, seagrass are marine flowering plants that have true roots and an internal vascular system.

Tell us 3 top important facts that people should know about seagrass ecosystems
1. Seagrass provide important ecosystem services such as habitat for commercial and subsistence fisheries, nutrient cycling, sediment stabilisation, and food for dugongs and green turtles. Globally, the ecosystem services provided by seagrass have been valued at $2.1 trillion per year.

2. Globally, seagrasses are as important as forests in storing organic carbon and can do so 35 times faster than rainforests.

3. Seagrasses globally are being lost at a rate of two football fields per hour, placing them among the most threatened ecosystems on earth.

What are the main challenges to seagrass ecosystems today? How can people protect them?
Over a billion people live within 50km of a seagrass meadow, and it is human activities that are reducing seagrass resilience and threaten seagrass survival.

The most obvious impact to seagrasses are direct human activities, such as coastal development, land reclamation and dredging. However, the most widespread and pervasive impact is indirect from reduced water quality due to sediments and fertilisers from poor farming practices washing down creeks, and sewage and stormwater from urban developments elevating nutrients and reducing water clarity in coastal waters.

The greatest challenge is raising awareness of the importance of seagrass ecosystems. The general population is oblivious to the fact that some activities on the land can have dire consequences to seagrass ecosystems, with significant follow-on effects to endangered or threatened animals such as dugong and sea turtle. People can protect seagrass ecosystems by considering the consequences of their actions/activities which may directly or indirectly damage seagrass. People can also help by raising awareness and assist by collecting critical information on the status of seagrasses. This information provides an early warning about coastal environmental problems before they become intractable. By working together with scientists and coastal managers, it is hoped that the impacts on seagrass meadows can be avoided. To protect our valuable seagrass meadows, everyone must work together.

If you were the voice of seagrass ecosystems what would you like to say to people?
“You might not notice us, and we may not be the most charismatic when you do, but we play a critical role in nearshore environments providing both direct and indirect services which humans benefit from. We are closely coupled to your health and wellbeing, and we need your assistance to remain healthy and to survive.”

Listen to Len talk more about the amazingly important, yet often overlooked, power of seagrass on Radio Australia, here.

Are Duging fussy eaters? Read Issue 45 of the Seagrass-Watch magazine, dedicated to the Dugong and their seagrass habitats, to find out. Download here.