Seagrasses of Australia

Benefits and Uses

Seagrass ecosystems provide habitats for a wide variety of marine organisms, both plant and animal. They serve as important nursery areas for juvenile marine animals, as well as providing food and shelter.

Mangroves, seagrasses, and saltmarshes only occupy about 1% of the seafloor, it is estimated that they capture and store up to 70% of the carbon in the marine environment.

In Western Australia, the very high productivity of seagrass communities supports the multi-million dollar Western Rock Lobster fishing industry.

Seagrass beds colonise and grow in areas of shallow water especially in the presence of unstable mud, silt and sand. The seagrass canopy reduces wave and current velocities, which reduces erosion and enhances sedimentation on the sea bed.

Seagrasses can improve water quality. Fast moving water stirs up the sediment on the bottom, which makes the water cloudy. When flowing water hits seagrass, it slows down allowing particles to settle. Seagrasses can also help by acting like a filter if there are too many nutrients in the water or sediment..

Seagrass wrack (leaves detached from the original plant) also plays a vital role as a microhabitat both in the water and along the shoreline. The accumulation of decaying seagrass on the shoreline provides food and habitat, and is a source of nutrient cycling for inshore estuarine ecosystems. When seagrass dies and begins to break down micro-organisms, such as bacteria, create fragments of decaying seagrass. This is then consumed by other micro-organisms and by prawns and other invertebrates. Other animals,including shore birds and fish, will then eat these invertebrates.

Dried seagrass was commonly used as housing insulation, until well into this century. Seagrass material was popularly used to thatch roofs in rural coastal areas in Europe and the UK from the seventeenth century.

Seagrass was extensively used to bind clay and soil, for example in the dikes of the Netherlands. Now seagrass drift is being used to produce a mulch applied to sand dunes to help with their stabilization.

It has also been used as a fertilizer for sandy soils and as a stock feed supplement.

Much of the literature about seagrasses state that " It is used as a material for stuffing pillows, mattresses and upholstery. It also used to make furniture, rope, woven baskets, matting and even shoes."

In fact the plants used for these and other crafts are generally freshwater and brackish water reeds which are abundanf China and SE Asia. he plants used for these and other crafts are generally freshwater and brackish water reeds which are abundant in China and SE Asia.

These are not classed as seagrasses, and don’t belong in the Families of true seagrasses: http://www.seagrasswatch.org/seagrass.html

The leaves and rhizomes of most true seagrasses do not have high lignin contents, and are not fibrous or resilient enough to make woven products.

The brackish and freshwater reed Phragmites australis, found in large natural stands in coastal and inland China, and species of Cyperus reed in South East Asia, are used for weaving into a range of products, including mats, shoes, baskets, etc.

The misconception has been long held, and would be very difficult to correct. The term “seagrass matting” has continued to be attractive across marketing and consumer sectors worldwide. Some marketing sites go as far as ascribing true seagrasses as the source product in seagrass matting.he plants used for these and other crafts are generally freshwater and brackish water reeds which are abundant in China and SE Asia.

These are not classed as seagrasses, and don’t belong in the Families of true seagrasses: http://www.seagrasswatch.org/seagrass.html

The leaves and rhizomes of most true seagrasses do not have high lignin contents, and are not fibrous or resilient enough to make woven products.

Thanks to Warren Lee Long, Environment & NRM Specialist, E: warrenleelong@bigpond.com for this information.