New book: Photosynthesis in the Marine Environment

Marine photosynthesis provides for at least half of the primary production worldwide. So Mats Björk, one floor down from The BalticSeaWeed blog, together with Sven Beer and John Beardall have publishyed the book “Photosynthesis in the Marine Environment”, available from Wiley.

Mats bok

“Photosynthesis in the Marine Environment constitutes a comprehensive explanation of photosynthetic processes as related to the special environment in which marine plants live. The first part of the book introduces the different photosynthesising organisms of the various marine habitats: the phytoplankton (both cyanobacteria and eukaryotes) in open waters, and macroalgae, marine angiosperms and photosymbiont-containing invertebrates in those benthic environments where there is enough light for photosynthesis to support growth, and describes how these organisms evolved. The special properties of seawater for sustaining primary production are then considered, and the two main differences between terrestrial and marine environments in supporting photosynthesis and plant growth are examined, namely irradiance and inorganic carbon. The second part of the book outlines the general mechanisms of photosynthesis, and then points towards the differences in light-capturing and carbon acquisition between terrestrial and marine plants. This is followed by discussing the need for a CO2 concentrating mechanism in most of the latter, and a description of how such mechanisms function in different marine plants. Part three deals with the various ways in which photosynthesis can be measured for marine plants, with an emphasis on novel in situ measurements, including discussions of the extent to which such measurements can serve as a proxy for plant growth and productivity. The final chapters of the book are devoted to ecological aspects of marine plant photosynthesis and growth, including predictions for the future.”

This is definetly on MY reading-list for the summer!


Seaweed in general

What is seaweed?

The word ”seaweed” is often used to describe perennial macroalgae. So, what are perennial macroalgae?

The term perennial is used in botany to describe how long a plant lives. Perennial means that the individual lives for several years. The opposite, only living for one year, is called annual.

A macroalgae is an algae we can see with the naked eye (macro – large) as opposed to microalgae (micro – small) where we need a loupe or a microscope to be able to see them.

Finally, we must define the term “algae”. (Hint: There is a very neat page on this on Wikipedia for those of you who wants a longer explanation.)

One of the major diffrences between algae and plants is that algae lack vascular tissue.

Plants have developed an equivalent to our bloodstream in order to transport nutrients and water that is taken up by the roots from the soil to all the parts of the plant. The vasciular system also transports nutrients that is produced in the leaves by photosynthesis to other parts of the plant.

In algae, water and nutrient uptake is directly over the thallus (body), making roots superfluous. Some algae have rootlike hapteres, but these only function as attachment to substrate.
Photosynthesis in algae occurs over the entire thallus, so there is no need for any advanced nutrient transportation system, beyond certain connectivity between nearby cells.

The flying insects evolved on dry land, wich favoured plants with flowers. Some land plants also use the wind to spread their pollen.

Algar do not have flowers. Instead, they reproduce with spores, gametes (egg and sperm) or in some cases cloning (a part of the algae is torn off then re-attaches to another surface, thus forming a new individual).

Some plants have returned to a life in water, but have kept their roots, vascular tissue and flowers. Amongst these are sea grass, water lilies and European bur weed.