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Anyone interested to work on Curaçao, Southern Caribbean?
My work evolves around nutrification of coral reefs on Curaçao and the wider Caribbean. From January 2013 onwards I will need up to three students to join me with my project. If you are interested in coral reef ecology, scientific diving and some lab work, please send me an email (j.denhaan1@uva.nl) and we can discuss possibilities. The fieldwork on Curaçao can be integrated into an internship or a BSc / MSc thesis. There are however some requirements you have to meet, e.g. you have to be an Advanced diver with at least 30 dives (see link for all requirements). For more information about the project I am involved in, please scroll down to the paragraphs 'FORCE' and 'Fate of Nutrients Entering Coral Reefs'.
Requirements to work on Curacao
What can you expect working on Curaçao?
On Curaçao we are stationed at the CARMABI Research Station (see link below) where we conduct scientific research in order to answer the questions 'What is the fate of nutrients entering coral reefs?' and 'What is the role of phytoplankton regarding nutrient dynamics?'
Our research is very hands-on. For most experiments we have to dive, which means we spend a lot of time in the water and on a small Boston Whaler boat. There are many small experiments that we conduct on the coral reefs. They include (1) nutrients in seawater, (2) composition of phytoplankton, (3) nutrient limitations, (4) abundance of macroalgae, turfalgae, cyanobacteria and corals, (5) nitrogen fixation of phytoplankton and turfalgae, (6) element ratio analysis, (7) uptake rate of nutrients by benthic communities and phytoplankton, (8) primary production, and (9) Hydrolab profiles where we make a 2-D visualization of the reef regarding light, pH, salinity etc.
CARMABI Research Station
Future of Reefsin a Changing Environment - FORCE
The FORCE project (see website) is an integrated research project which takes an ecosystem approach, linking social and ecological aspects towards managing Caribbean coral reefs in the face of climate change. Being part of the natural sciences group ourselves, we investigate the fate of nutrients entering coral reefs (from land, atmosphere, oceanic). Nutrients entering reef environments are often assumed to be available to stimulate the growth of benthic macro algae but in reality, many of these nutrients may be taken up by phytoplankton and not become directly available. My group looks at the fate of nutrients entering reefs and seeks early warning indicators of nutrification by sampling the phytoplankton community. Outputs will inform whether nutrification events should be modeled as leading to an increase in benthic macro algal growth rates and if so, to what extent. For more information, see paragraph below.
FORCE website
Fate of Nutrients Entering Coral Reefs
The figure below is an oversimplification of nutrient distributions throughout part of the food-web, of which the red arrows are the ones we are most interested in. To investigate whether phytoplankton can function as a type of 'nutrient buffer' before nutrients running off from land become available to macro algae, many experiments are being conducted. With these experiments we hope to give a clear indication of the fate of nutrients entering coral reefs.
About myself: "Being a marine biologist"
It is great to be a marine biologist. I am very fortunate to be able to combine two of my great passions: marine biology and diving. I am very thankful that the University of Amsterdam gave me the opportunity to pursue a PhD in Aquatic Microbiology together with Dr. Petra Visser and Prof. Dr. Jef Huisman. The project we are currently working on is titled 'Fate of Nutrients Entering Coral Reefs', and is part of a much larger project called FORCE. What is very exciting about this FORCE project is that it not only focuses on natural science, but also social science. The ultimate aim of FORCE is to provide coral reef managers with a toolbox of sustainable management practices that minimize the loss of coral reef health and biodiversity in the Caribbean. For more information on FORCE and my own project, please scroll down to sections 'FORCE' and 'Fate of Nutrients Entering Coral Reefs'.
Before going to the University of Amsterdam
I started out as a farmer. In2004 I graduated from the HAS Den Bosch, the Netherlands, where I studied Plant Breeding, mostly flowers and turf grasses. I however felt that this was not truly what I wanted, so I went to the Wageningen University, the Netherlands, where I pursued a MSc in Earth System Science (see link). For my thesis I workedatthe Bonaire National Marine Park (see link) together with Dr. Ramon de Leon where I finally felt I had found what I was looking for. The combination of science and sports (diving) felt great. I however did not have the feeling I knew enough about marine biology, so after finishing my MSc I took off to the University of Guam, Marine Laboratory (see link), where I worked for 1,5 years as a phycologist (one who studies algae). Together with my advisor Dr. Tom Schils (picture below, left side), I participated in many coral reef monitoring studies, scientific articles and even co-authored on a field guide titled 'Marine Plants of Guam'. After my time on Guam I felt I was ready for a PhD, and I am happy I have been given the opportunity now.
Earth System Science - Wageningen University
Bonaire National Marine Park
University of Guam Marine Laboratory
Being a diveinstructor
Teaching new students to dive is very rewarding. You introduce them to a world that isyet unknown to them.Theyusually start outa bit anxious, but once theyhave successfully completed the dive training, they are very excited. I always teach them a bit more than is required. I believe it is important to make them extra aware of the new environment they enter. Coral reefs are very precious and have to remain protected as much as possible. Simple tricks as teaching students not to touch corals and introducing them to the famous saying 'Never take anything from the water but pictures and never leave anything in the water but bubbles' is something I live by. Tourism is something that can be very damaging to coral reefs, but we also need it. Take the Bonaire National Marine Park for example, this national park basically runs on tourism. Sustainable integration is the key.
I am very thankful to the late Larry Klinehoffer, course director at GTDS dive-shop in Guam, who made me a dive instructor (picture above in the center, wearing sunglasses).
Guam Tropical Dive Station (GTDS)
Me and phycology
Phycology is a very interesting field. Most people however under-appreciate phycology, regarding it as 'that slimy stinky stuff'. It is ecologically however veryimportant. I never really saw myself as one who studies (macro-) algae, but Dr.Tom Schils changed all ofthat. His passion formacro algae affected me(in a positive way!)and I will now also call myself a phycologist. Just for those how don't know much about algae check out AlgaeBase.org or phycology.net (see links). 10 points for the person who can tell me which picture directly below is neither an algae nor a cyanobacteria...
www.algaebase.org
www.phycology.net
Answer to algae question above
Below you can see some pictures of macro algae I collected during the 2010 International Excursion Tropical Marine Biology on Curaçao. These algal samples were taken from the field and put into petri-dishes to show students that there is in factawide variety of species, that it can be quite colorful and very interesting. For those interested injoining the International ExcursionTropicalMarineBiology, please visit the website below.
International Excursion Tropical Marine Biology - Curaçao
