Researching Algae, the Unsung Heroes of Aquatic Food Webs

[The original version of this post is published on the Wading Through Research blog of the Florida Coastal Everglades Long Term Ecological Research program]

Why is it important to study algae? To start with, algae produce ~ 50% of the oxygen on planet Earth, they are food for small and large animals that in turn are eaten by people, but they also recycle nutrients and absorb CO2 from the air; by existing and doing their own thing, these microorganisms provide these so called ecosystem services to human beings (Fig. 1). Moreover, as algae reproduce fast and are often adapted to specific environmental conditions, understanding how many species of algae, and which ones, live where and why give us cues as to the health of aquatic ecosystems, such as rivers, lakes, and wetlands.

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Fig. 1. Simplified scheme of the role of algae in food webs (from my Ph.D. Thesis).

How did I get to do research on algae? For my Environmental Science MSc dissertation project, I worked in the northern Italy’s Alps studying Passerine bird migration, then my career path took me to office-based research on air quality and climate change. Wanting to go back to field research, I got a Ph.D. opportunity at University College London to study the biodiversity and biomass of microscopic algae in the Okavango Delta, a subject and a place I didn’t know much about, apart from biology courses and natural science readings. Between 2009 and 2010, I spent ~3 months in Maun (NW Botswana), to carry out the necessary sampling in this incredible, remote, and near pristine wetland in the middle of the Kalahari; another ~ 70 months were needed to master and apply taxonomy and microscope skills, conduct statistical analyses, read, think, and write my Thesis, as well as working to support my graduate studies.

Fast-forward 8+ years, here I am in sunny Miami, some 8,000 km away from the cold and misty mountain pass where I did my MSc research and 12,200 km from the Okavango, to work on another amazing wetland, the Everglades, as part of a Postdoctoral Associate contract in Dr. Evelyn’s Gaiser laboratory at Florida International University (FIU). After a few months at FIU putting together a database for the Comprehensive Everglades Research Plan Monitoring and Assessment Plan (CERP-MAP) and planning my publications, I decided, with my postdoc and Ph.D. advisors, to undertake an ambitious comparative study of patterns and drivers of species richness and life-history strategies in the Okavango and Everglades. We estimated that, the Okavango hosts, on average, ~80 species of algae in each sampling site, the Everglades have ‘only’ ~ 20 (Fig. 2). This is likely due to phosphorus scarcity, habitat fragmentation due to water diversion schemes, and nutrient pollution in the Everglades whereas the Okavango is still a near pristine wetland. Moreover, Florida is a long peninsula, while the Zambezi ecoregion in Africa has been historically well connected so that organisms may be able to better disperse to and from this wetland than in the Everglades. For more information, our paper “Algal richness and life-history strategies are influenced by hydrology and phosphorus in two major subtropical wetlands” is published in this month’s issue of Freshwater Biology.

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Fig. 2. Map of estimated algal richness and photos from the air: Okavango (above) and Everglades (below; photo by Franco Tobias). Okavango (site averages); UPH= Upper Panhandle; LPH=Lower Panhandle; XAK=Xakanaxa; BOR=Boro; SAN=Santantadibe.Everglades; LKO=Lake Okeechobee; LOX=Loxahatchee; Out_ENP=Outside of Everglades National Park (including the Water Conservation Areas, WCA 2 and 3); ENP=Everglades National Park.

Although, in the Okavango, the flooding cycles have a stronger influence on species richness, as compared to phosphorus in the Everglades, maintaining and restoring the natural hydrology in these wetlands is critical for the preservation of algal communities, and thus for the health of food webs. Due to their outstanding geographic features and biodiversity, both these wetlands are protected as World Heritage sites, and are included in the Ramsar Convention on Wetlands of International Importance, and so it is critical to keep monitoring these ecosystems.

What’s next?

I am currently researching how algal dominance changes with nutrients and hydrology in the Everglades, which is relevant for freshwater flow and water quality restoration scenarios. I am also trying to create opportunities for comparative research in other subtropical wetlands. Last September, I visited the Nanjing Institute of Geography and Limnology of the Chinese Academy of Sciences and, with other 800 experts, attended the excellent 10th INTECOL Wetlands conferencein Changshu. I presented my comparative work and co-organized a workshop on future directions in wetlands studies, strengthened previous connections and made new ones with various colleagues working in Asia, South America and Australia. In June, other FIU scholars and I are planning to present our work at the next Society of Wetland Scientists’ meeting in Puerto Rico (“Celebrating Wetland Diversity Across the Landscape: Mountains to Mangroves”), where we aim to foster new collaborations with ecologists conducting research on wetland ecosystems and food webs in Central and South America, and beyond. Moreover, Dr. Gaiser, Dr. Barry H. Rosen (USGS) and I co-organized a special session on how algae / periphyton mats may respond to different nutrient and hydrology scenarios in the Everglades for the Greater Everglades Ecosystem Restoration (GEER 2017) conference. As wetlands are facing unprecedented anthropogenic impacts due to, for example, land use change, water diversion, and global warming, such collaborations among scientists, and between us and policy makers, are crucial to foster and inform sustainable management practices and strong conservation and restoration activities.

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Fig. 3. (from top to bottom) In front of the conference venue with Drs. Wolfgang Junk (Federal University of Mato Grosso, Brazil), Max Finlayson (Charles Sturt University, Australia) and Xuhui Dong (Aarhus Institute of Advanced Studies, Denmark and Chinese Academy of Sciences); a picture from one of the conference fieldtrips to Shanghu Lake.
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INTECOL Wetlands in Asia after 36 years

On September 19-24 2016, about 800 wetland scientists, including myself, gathered in the beautiful city of Changshu (Jiangsu province, China) to share their findings and relative interpretations on a variety of topics: from biodiversity to pollution, from Ramsar-based wetland conservation to carbon sequestration and much more, including socio-ecological dimensions linked to wetland sustainable / unsustainable management.

Whilst participating in the 10th INTECOL Wetlands conference, it was such an honor to share ideas with, among others, Dr. Brji Gopal (photo below), who organized the 1st edition (attended by about 100 scholars) in New Dehli (India) in 1980.

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With Dr. Brji Gopal in the INTECOL Wetlands plenary room.

A team of leading experts wrote the Changshu Declaration, a two page document with clear demands for policy makers on wetland conservation and sustainable management in the global environmental change era, otherwise called the Anthropocene. This was signed and approved by acclamation in the final plenary, after an important talk on wise use in Ramsar sites by Dr. Max Finlayson, another key leader of this international community of wetland scientists.

The following are a few other highlights of my 10.5 day trip (+ 2.5 travelling) to China:

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The cross-Pacific route from the United States to China.

1) I was invited by my friend and University College London colleague Dr. Xuhui Dong to give a seminar at the Nanjing Institute of Geography and Limnology (NIGLAS) of the Chinese Academy of Sciences. I ended up presenting a 1hr summary of my last 8 years of research on the algal communities of the Okavango Delta (topic of my PhD), and Everglades, which I am investigating for my post-doc at FIU. [What a great challenge it is to compare the biodiversity and ecology of microscopic algae in such amazing ecosystems!]. My Chinese colleagues’ great discussion points and friendly hospitality made this experience unforgettable: XIEXIE! (‘thank you’ in Chinese).

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Starting my seminar at Nanjing Institute of Geography and Limnology (NIGLAS).

2) I gave my talk on my comparative research in subtropical wetlands, and co-moderated, with Guodong Wang (Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences), the “Wetlands: Monitoring and Management” session. It was the last day…but there was a very good participation, and we had the chance to discuss (& get advice from Max Finlayson), and share contact details, for about 45 minutes at the end!

3) The International Network for Next Generation Ecologists (INNGE) workshop went very well, with about 30 attendees who participated in a lively discussion about ecosystem services and disservices (for example, polluted urban wetlands with their poor water quality negatively impact homeless people living around it), the challenges of mixing anthropocentrism and ecocentrism to take care of people and the Nature, and innovative wetland research and technologies, such as the Waterharmonica initiative. Kudos to Jorge Ramos (Ph.D. Candidate at Arizona State University, ASU) for leading the team of organizers, also including Dr. Xin Leng (ASU), and myself.

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During our INNGE workshop “The Next Generation of Wetland Science: Ecosystems, Applications, and Engineering”

And, for what I could experience in less than 2 weeks, China is a stunning country with a multitude of colors, places, peoples, incredible food, beautiful temples, and natural surroundings, such as the Shanghu Lake (below), part of excursions to other wetlands such as the Shajiabang National Park, where we were welcomed by a gigantic video-screening of its beautiful Nature that was set up just for us, lucky INTECOL attendees!

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During the excursion to Shanghu Lake, water lotus leaves a prominent feature of this waterscape.

 

 

 

Freshwater ecology: algae, wetlands and biodiversity

Welcome to my website! I am a freshwater ecologist at Florida International University doing research on algae in subtropical wetlands, such as the Everglades and the Okavango Delta (Botswana). I obtained an MSc in Environmental Sciences at the University of Milano Bicocca and a Ph.D. in Freshwater Ecology at the Environmental Change Research Centre, University College London.

My main interests are the ecology, taxonomy and distribution of algae (such as diatoms and desmids) in relation to hydrology, nutrient concentrations and habitat. More broadly, I am passionate about biodiversity, conservation and climate change.

I work in Dr. Evelyn Gaiser’s research group in the School of Environment, Arts and Society and Southeast Environmental Research Center. For more information please visit our lab page http://algae.fiu.edu and the Florida Coastal Everglades Long Term Ecological Research Network website. We also have a “Diatom of the month” blog series: http://floridacoastaleverglades.blogspot.com.

On February 2nd, it was World Wetlands Day. More than 1 billion people make a living from wetlands, but too many have already been destroyed. We need to study and talk about wetlands to conserve them and use their resources as sustainably as possible #WorldWetlandsDay #WetlandsForOurFuture

Algae are at the base of the food webs of wetlands, lakes, rivers and seas so they too need our scientific and public attention because they give people oxygen, food and other so called ‘ecosystem services’ such as water purification. Let’s not forget about these invisible organisms so precious for all life on Earth!

Get to know more about diatoms: http://fcelter.fiu.edu/data/database/diatom/;

http://westerndiatoms.colorado.edu/ & desmids: http://www.desmids.nl/