Book Review: Rhodolith/Maërl Beds: A Global Perspective


This new book on Rhodolith/Maërl Beds* has been much anticipated by the rhodolith research community. With over four years in the making, it is a volume tributed to Prof. Rafael Riosmena-Rodríguez, who dedicated 25 years particularly to the study of the taxonony of coralline algae and sadly passed away earlier this year. Prof. Riosmena-Rodríguez will be very much missed by the rhodolith research community and this book is an important tribute.

The book begins with the role of rhodolith/maërl beds in modern oceans, with chapters on natural history and biodiversity around maërl beds, rhodoliths as climatic archives, modern day threats of ocean acidification on maërl and economic importance. The role of rhodolith in historical oceans and the geological significance is explored by the following section, with a particular focus on the Mediterranean area as well as the North Atlantic sedimentary dynamics. The final part of the book covers the conservation status of rhodoliths globally and serves to be an important summary of current state of regional knowledge of rhodoliths in the major geographic areas.

“These marine beds occur worldwide, from the tropics to the poles, ranging in depth from intertidal to deep subtidal habitats and they are also represented in extensive fossil deposits.”

Overall, this is a much needed edition for marine biology libraries around the world and highly recommended for students of one of the four macrophyte dominated benthic communities. I made a blog post about attending the International Rhodolith Workshop in Granada and one of the key conclusions of the 2015 workshop in Costa Rica was that international recognition is needed for rhodolith habitats to ensure their protection. This book is an important step required to make this possible. It serves to be a useful and comprehensive introduction summarizing the multidisciplinary study of global rhodoliths/maërl beds.

*The term maerl originally refers to the branched growth form of Lemoine (1910) and the term rhodolith is sedimentalogical or genetic term for both the nodular and branched growth forms (Basso et. al, 2015).


Basso (2015) Monitoring deep Mediterranean rhodolith beds. Aquatic Conservation Marine and Freshwater Ecosystems. 26:3. doi:10.1002/aqc.2586.

Lemoine (1910) Répartition et mode de vie du maërl (Lithothamnium calcareum) aux environs de Concarneau (Finistère). Annales de l’Institut Océanographique. 1: 1–29.

Riosmena-Rodríguez, R., Nelson, W., and Aguirre, J. (Editors) (2016) Rhodolith/Maërl Beds: A Global Perspective, Coastal Research Library 15, VIII, 368pp.DOI: 10.1007/978-3-319-29315-8


Before the Flood

“Before The Flood is the product of an incredible three-year journey that took place with my co-creator and director Fisher Stevens. We went to every corner of the globe to document the devastating impacts of climate change and questioned humanity’s ability to reverse what may be the most catastrophic problem mankind has ever faced. There was a lot to take on. All that we witnessed on this journey shows us that our world’s climate is incredibly interconnected and that it is at urgent breaking point.”

-Leonardo DiCaprio, UN Messenger of Peace on Climate Change (Source: Wikipedia)

Watch the full film “Before the Flood” on YouTube till 6th November.

World Oceans Day Quiz


Happy World Oceans Day 2016! This year for World Oceans Day (8th June) we have prepared a special World Oceans Day Quiz! Some answers can be found dotted around this blog, with others about topical issues affecting the oceans today. Try the quiz today and test your knowledge of the oceans and its habitats!

Question 1: Why do the oceans appear blue in colour?
because the oceans scatter red light and absorb blue light.
Try again! Hint: If the oceans absorb it than it doesn’t reach our eyes!
because the oceans scatter both red and blue light.
Try again! Hint: If the oceans scatter red light than the oceans would appear red
because the oceans absorb red light and scatter blue light.
Correct! The oceans scatter blue light so they appear blue when the light reaches our eyes! Further more, red light does not reach the deep sea as it is absorbed so many deep sea creatures are red in colour, so they appear black to predators and prey.
Question 2: Where are the largest rhodolith beds in the world found?
South Western Australia.
Abrolhos Shelf in Eastern Brazil.
The Abrolhos Shelf rhodolith beds cover an estimated 21 000 square km area- an area nearly the size of El Salvador! More can be found at the blog post link below.
At the Mouth of the Amazon.
Incorrect, although newly discovered rhodolith beds have been found in this area
  Rhodolith beds (© Rodrigo L. de Moura)
Question 3: Coral bleaching is caused by…
Predatory sea stars such as the crown-of-thorns starfish who eat the coral
changes in conditions causing the coral to expel symbiotic algae from their tissue.
Correct! When corals are stressed by changes in temperature, light or nutrients they expel the symbiotic algae living in their tissue (known as zooxanthellae), turning white.
the presence of symbiotic animals such as worms living in the coral.
This answer is incorrect!
  Coral Bleaching Photograph by XL Catlin Seaview Survey Copyright of National Geographic reproduced for Educational Use only

Continue reading “World Oceans Day Quiz”

Book Review: “The Sea Around Us” by Rachel Carson


“We live in a scientific age; yet we assume that knowledge of science is the prerogative of only a small number of human beings, isolated and priest-like in their laboratories. This is not true. The materials of science are the materials of life itself. Science is part of the reality of living; it is the what, the how, and the why of everything in our experience. It is impossible to understand man without understanding his environment and the forces that have molded him physically and mentally. The aim of science is to discover and illuminate truth. And that, I take it, is the aim of literature, whether biography or history or fiction. It seems to me, then, that there can be no separate literature of science. My own guiding purpose was to portray the subject of my sea profile with fidelity and understanding. All else was secondary. I did not stop to consider whether I was doing it scientifically or poetically; I was writing as the subject demanded. The winds, the sea, and the moving tides are what they are. If there is wonder and beauty and majesty in them, science will discover these qualities. If they are not there, science cannot create them. If there is poetry in my book about the sea, it is not because I deliberately put it there, but because no one could write truthfully about the sea and leave out the poetry.”

– Rachel Carson during her acceptance speech of the Non fiction award at the National Book Award 1952

Rachel Carson’s second book in the sea trilogy; “The Sea Around Us” is a classic work published in 1951. Described as one of the most successful books written about the natural world, this is a poetic narrative about the life history of the oceans. The Gray Beginnings shares with us the shadowy, primeval beginnings of the Earth and its early environment, exploring the geological theories as well as the evolutionary milestones throughout the history of life. The Pattern of the Surface starts off at the surface waters of the oceans and wonderful world of the plankton- wandering through the interlocking food webs and seas of the world. The Changing Year poetically talks about the changing realm of the sea; the response of marine life through day and night; seasons; and years.The Sunless Sea is about the history of deep sea exploration and Hidden Lands discusses early hydrographic surveying to chart the depths of the continental shelf. The Long Snowfall details the phenomenon of marine snow and Globigerina oozes. The Birth of an Island and The Shape of the Ancient seas ends the Part One entitled Mother Sea.

The Restless Sea begins with Wind and Water a poetic narrative about the life history of the waves and coastal seas, leads on to Wind, Sun, and the Spinning of the Earth; about ocean currents and their oceanographic discovery. The Moving Tides looks at the tidal rythms and the intertidal creatures. Part Three about Man and the sea about him starts off with The Global Thermostat looks at the close relationship between climate and the pattern of ocean circulation. Wealth from the Salt Seas looks at the minerals in seawater and The Encircling Sea starts off with a quote from Homer and the Ancient Greek view of the ocean. With an Afterword updating some of the science by marine biologist Jeffrey Levinton, this book is an imaginative and sensitively emotional account of the sea around us. An absolute joy to read! 


Americal Scientist

The Guardian