Monday, 6 June 2016

Internship Diaries: A Wetlands Research Adventure- Introduction

I will soon be starting a three month full-time internship as a Wetlands Research Officer.  I plan on writing posts each week, keeping a record of what I have learnt and the adventures that I have been on. 

My role in the internship will be to research constructed treatment wetlands and water quality issues related to a local wetland nature reserve.  I will also get involved in other conservation/ ecological issues at the reserve.

Photo by Svetlana Makarova


Thursday, 3 March 2016

All About Algae

At university I spent some time researching the different uses for microalgae and I have grown quite fond of the stuff.  This post will hopefully cover the algae basics and explain the various uses of algae. 


An experiment involving microalgae Alice Wickman
An experiment involving microalgae 

What are algae? 

The word algae represents a large group of organisms from different genetic groups.  They are usually photosynthetic aquatic organisms that can be found in freshwater or marine environments.  

There are two main types of algae:
  • Macroalgae- multicellular, often found in marine environments as seaweed 
  • Microalgae- unicellular 
Even though some macroalgae may look like plants, they lack the complex vascular structures that plants possess and are not classified as such.
Macroalgae and microalgae. Images by Dozens at en.wikipedia and CSIRO
Macroalgae and Microalgae. Images by Dozens and CSIRO
Most algae contain chlorophyll (a green pigment) and can manufacture their own food through photosynthesis.  They conduct photosynthesis within cellular structures called chloroplasts.

There are different genetic groups of algae, including:

  • Brown algae (Phaeophyta)- Most seaweeds are members of phaeophyta.  They get their colour from several brownish carotenoid pigments in their cells.
Brown Algae (Image by B.navez)
Brown Algae (Image by B.navez)
  • Red algae (Rhodophyta)- Multicellular algae charecterised by their clear red or purple colour, which is due to accessory pigments called phycobilins.  Red algae structures are often highly branching.
Red Algae (photo by Johnmartindavies)
Red Algae (Image by Johnmartindavies)
  • Green algae (Chlorophyta)- Various species in the kingdom protista.  Can be unicellular, multi-cellular, coenocytic (having more than one nucleus in a cell) or colonial.  They get their colour from the chloraphyl in their cells. 
Green algae (Photo by Tristan Schmurr)
Green Algae (Image by Tristan Schmurr)
  • Cyanobacteria- a group of bacteria that obtain energy through photosynthesis.  Often referred to as blue-green algae, even though they are not related to the other algal groups.
Cyanobacteria (Image by Doc. RNDr. Josef Reischig, CSc.)
Cyanobacteria (Image by Doc. RNDr. Josef Reischig, CSc.)
  • Diatoms- Unicellular organisms of the kingdom protista, characterized by a silica shell.
Diatoms (Image by Prof. Gordon T. Taylor)
Diatoms (Image by Prof. Gordon T. Taylor)
  • Euglenophyta- a small group of protists that are mostly unicellular and aquatic.  Some photosynthesise, others are heterotrophic and can ingest/absorb their food.
  • Dinoflagellata- a large group of protists that have flagella (whip like tail structures that help the cell to move).  Some are heterotrophic, some are photosynthetic and some are endosymbionts of marine animals and protozoa

Using algae for waste water treatment
Water pollution can seriously harm aquatic life and impact on human health.  Therefore, waste water treatment is required. Traditional waste water treatment practices can be expensive and energy intensive. However, as populations increase, the demand for water treatment infrastructure increases. It therefore makes sense that more sustainable methods are developed and used.

One of my university research projects was looking into the water treatment efficiency of microalgae compared to aquatic plants in constructed wetlands. 

I talked a bit about constructed wetlands in an earlier blog post, which explains how constructed wetlands utilise the natural processes involving wetland plants and soils to remove pollutants from waste water.  Microalgae can remove excess nutrients in a similar way to wetland plants, by taking them up and using them and using them for growth. They can also remove nutrients and other pollutants, such as heavy metals, indirectly by increasing the dissolved oxygen content and pH of the waste water during photosynthesis.  

Therefore, in controlled cultivation systems, microalgae can be grown and used to treat different types of waste water, including industrial and domestic waste waters. 

The common species used in this process include:

  • Chlorella vulgaris 
  • Scenedesmus obliquus
  • Phormidium bonheri
There are different types of algae cultivation systems, these include:
  • Raceway ponds
  • Photobioreactors
  • Immobilised algae systems
  • Algae biofilm systems
Algae Raceway Pond and Photobioreactor (Images by IGV Biotech)
Each type of algae cultivation system has its own advantages and disadvantages.  One advantage of Immobilised algae systems is that that the algae can easily be harvested and used for a secondary purpose.  One of these secondary purposes includes algae biofuel production. 

Algae Biofuel
Algal biomass can be converted into different types of biofuel, including biogas by fermentation or the algal oils can be extracted and transformed into biodiesel though a process called transesterification.  

The image below displays a microalgal cell and the different processes that take place within the cell, which are involved in biofuel production.  

Sunlight and carbon dioxide are used in the Calvin Cycle, a process of photosynthesis that produces molecules involved in fatty acid and starch synthases.

  • The starch can be used to make ethanol or biogas (biohydrogen/ Bio-H2).
  • The fatty acids are used to make triacylglycerol’s within the cell, which can be extracted and used to make biodiesel. 

The processes within a microalgal cell involved in biofuel production. Figure adapted from Radakovits et al. (2010)
The processes within a microalgal cell involved in biofuel production. Figure adapted from Radakovits et al. (2010)
Production of biogas from algae was proposed in the early 1950s and from 1980 to 1996 the US Department of Energy supported the Aquatic Species Program (ASP), with the specific goal of producing oil from microalgae. 

The ASP paved the way for algae biofuel research.  Thousands of different species were isolated and tested for their suitability for biofuel production. 

There has since been lots of research into the potential for large scale algae biofuel production but a sustainable and cost-effective methods is yet to be found.  

My undergrad research was looking into increasing algal oil production by growing the algae in different nutrient conditions. 


Algae dietary supplement (Image by Perdita at the English Wikipedia)
Algae dietary supplement
 (Image by Perdita at the English Wikipedia)
Other uses for algae
The other uses of microalgae include:

  • Animal feed
  • Nutritional suppliants 
  • Cosmetic products 
  • Crop fertilizer 



Conclusions
Algae are pretty cool; they can be used for some really amazing things and should definitely be appreciated more! 

Tuesday, 2 February 2016

Happy World Wetlands Day 2016


Its the 2nd February, the anniversary of the signing of the Ramsar Convention in 1971, which makes it World Wetlands Day.


HAPPY WORLD WETLANDS DAY!
Different Wetland Habitats
Different Wetland Habitats

Why celebrate wetlands?

World wetlands Day has been celebrated internationally since 1997 in order to raise public awareness of wetland values and their benefits to people. 

Wetlands are important for maintaining healthy and productive landscapes by:

  • Providing habitats
  • Maintaining water quality
  • Providing natural deference's against flooding and storm surges
  • Reducing coastal erosion
  • Storing large amounts of carbon as peat
The Values of Wetland Habitats  By Alice Wickman
The Values of Wetland Habitats 

They also provide valuable resources for humans, such a food and building materials, as well as fantastic areas for recreational and spiritual activities.  

Unfortunately, wetlands are under threat and more than 64% have disappeared since 1900.  

The main threats to wetlands include: 
  • Human attitudes 
  • Climate change 
  • Pollution 
  • Invasive species 
  • Land use changes
In the past, wetlands have been viewed as 'wastelands' and have been depicted negatively in films or books, such as Wes Craven's (1982) Swamp Thing.  Even the phrase 'bogged down' has negative connotations.  


Swamp Thing. Art by Bernie Wrightson
Swamp Thing. Art by Bernie Wrightson
World Wetlands Day aims to change the public's perception of wetland habitats and raise awareness of their values. 

The theme for World Wetlands Day 2016 is Wetlands for our future: sustainable livelihoods. 


It is important that wetland habitats are maintained and restored in order to maintain their important functions and protect our landscapes. 


This is incredibly significant in terms of the wide-spread flooding that the UK has experienced recently.  


Maintaining or restoring upland wetland areas could help to slow down the flow of ground water (as shown in the diagram above) and help flood deference cope with excess water. 


Projects, such as The Working Wetlands Project , aim use the natural vales of wetlands by restoring or creating wetland habitats that will help manage flooding, as well as reduce water treatment costs and provide important wildlife habitats.  Hopefully, World Wetlands Day will continue to raise awareness of the importance of wetlands so that more restoration projects can continue. 


Wetland habitats are beautiful, varied and ever-changing, which makes them incredibly fascinating to study. 


Tuesday, 28 April 2015

Florida's Cypress Swamps


Cypress swamp at corkscrew swamp and the Disney Wilderness preserve 
During my trip to Florida, I was able to see three different examples of a cypress swamp. These were corkscrew swamp, Florida Gulf Coast University (FGCU) and the Disney wilderness presearve . The swamp at the Disney preserve was an example of a lake edge cypress swamp and was very small.  The swamp at FGCU was an example of a cypress dome and the swamp at Corcskrew was a large pristine cypress strand.
Bald and pond cypress leaves,   air plant, FGCU cypress swamp
Bald and pond cypress leaves, 
air plant, FGCU cypress swamp

What are cypress swamps? 
Cypress swamps are communities that are dominated by cypress trees. Cypress trees are conifers, although the do shed their needles. There are three main species of cypress tree: bald cypress (Taxodium distichum), pond cypress (Taxodium ascendens) and Montezuma Cypress (Taxodium mucronatum). However, the last species is only found in Mexico and southern Texas.  Therefore, pond cypress and bald cypress are the two species that dominate Fllorida's cypress swamps. 

Pond and bald cypress can easily be identified by their leaf shape. Bald cypress leaves are linear with branchlets spreading.  Whereas, Pond cypress leaves are awl-shaped, and press against the branchlets (appressed), with branchlets generally ascending (as you can see in the photo to the right).

There are also differences between the two species in their habitat preference, with pond cypress preferring sites that are nutrient poor and relatively isolated from the effects of river flooding or large nutrient inputs.

Often growing with the cypress trees are Tupelo trees (Nyssa spp.): water tupelo (Nyssa aquatica) and black tupelo (Nyssa sylvatica).  Bald cypres can usually be found with black tupelo and pond cypress with  water tupelo.

Other plants growing in the understory of this habitat may include: swamp fern, spikerush marsh fleabane, buttonbush, willow and wax myrtle. Epiphytes or airplants attach themselves to other living plants and grow on the trunks and branches. Instead of getting water and nutrients from the soil, epiphytes use photosynthesis to create energy and obtain moisture from the humidity in the air.

10-15% of Florida's landscape is dominated by cypress wetlands, of which there are many different types, including: the scrub cypress forests of South Florida, cypress domes , cypress strands, tall floodplain forests and lake edge cypress swamps. 
Alligator flag in a deep solution
hole, cypress strand,
lake edge cypress swamp
Cypress Domes
Cypress domes form in depressions known as solution holes. These are depressions in the limestone bedrock which have been broken down over time due to the acidic by-product of decomposition. The roots of the cypress trees are then able to break through the bedrock and take hold to grow.
Cypress domes are usually dominated by pond cypress and are most abundant in central Florida. They form when the tallest trees grow in the deepest water at the centre of the swamp, and the smaller trees grow in the shallow water at the edges. This creates a domed effect, when viewing the swamp from the side. Sometimes, cypress domes develop a hole in the centre, where the cypress trees are unable to grow.  This is because the solution hole is too deep for cypress trees to become established.  Here, species such as alligator flag (Thalia geniculata) may survive.  As these deeper solution holes usually hold water year-round, they are an important refugia for aquatic animals like alligators. Cypress domes are not always dome-shaped however, and other factors, such as fire and growth rate can affect their appearance.   
Clay soils often prevent upwelling of ground water into the system. Therefore, cypress domes usually contain low nutrient levels due to the water inflow being dominated by precipitation.

Cypress Strands 
Cypress strands develop in an elongated or linear formation. They are typically much larger than domes and develop where the ground level is slightly lower than the surrounding communities. The picture in to the left (centre) displays a cypress strand (Corcskrew swamp) adjacent to a wet prairie. Just slight a elevation in topography has created these two distinct habitats. Cypress strands  are usually flooded by slow moving water, which brings in nutrients and allows bald cypress to become established. 

Lake edge cypress swamp  
Lake edge cypress swamps are also dominated by bald cypress.  They are found on lake margins where they are influenced by seasonally fluctuating water levels.  Lake edge swamps also receive upland runoff, influencing nutrient levels.



Monday, 27 April 2015

The Mangroves of Florida

I was lucky enough to spend ten days travelling around southern Florida two months ago. The main purpose of my trip was to learn about the different wetland types in Florida for my MSc course. However, the trip really did feel more like a holiday (although, Christian will really hate me saying this). We were so busy and did something different everyday but I enjoyed it so much, it didn't really feel like work. 

As part of my assessment for the field trip, I had to write a blog post about what we did each day, you will find these posts entitled 'The Florida Diaries' below. I saw so many amazing species, some of which were rare and threatened, but there were two particular habitat types that really stood out for me. These were mangroves and cypress swamps.  Both were new experiences for me and I really hadn't seen anything like them before. I have decided to write my next two blog posts about these habitats, starting with mangroves.

Red mangroves at the Florida Keys
Red mangroves at the Florida Keys
Where did I visit?
For the majority of the trip, we stayed at the Vestor field research station in Bonita springs, located opposite the mangrove islands. On two occasions we had the opportunity to borrow the field station's canoes and paddle out into the mangrove system.  This was probably the best opportunity to explore the mangroves and really see the habitat structure ourselves. 

The MSc group exploring the mangroves at the Vestor field station 
     Some of the other places where we were able to see the mangroves included: Lovers Key state park10,000 islandsDing Darling Wildlife Refuge, The Florida Keys and Barefoot beach). 

 What are Mangroves?
Mangroves are not a single taxonomic group. They are a collection of Woody tree or shrub species that are classed as mangroves due to their common adaptations, such as aerial roots and salt excretory glands.  

Map showing the global distribution of mangroves
Map showing the global distribution of mangroves with modelled estimates of above ground biomass per unit area. Figure adapted from Hutchison et al. (2014). 


The map above shows the global distribution of mangroves. They dominate approximately 75% of the world's tropical coastline, in tropical and sub-tropical lattitudes. The Global distribution of Mangroves is determined by ocean currents, sea temperature and hydrology as these factors affect the ability of mangroves to colonise and grow. They prefer areas with high rainfall, soft sediment, low wave energy and minimum temperatures of 19ÂșC. 

The mangroves of Florida
There are over 55 species of mangrove in total, but just three of these can be found in Florida. These species are the: white mangrove (Laguncularia racemosa), black mangrove (Avicennia germinans) and red mangrove (Rhizophora mangle). 

There are an estimated 469,000 acres of mangroves in Florida and >90% of these occur in the four southern counties of Lee, Collier, Miami-Dade, and Monroe. The greatest abundance of mangroves can be found in these areas due to the fresh water and nutrient inputs, as well as low wave energy.

Red and white mangroves have been reported as far north as 29°N latitude, near the Ponce de Leon Inlet on the east coast and Cedar Key on the west coast. Black mangroves have been found further north, as they can tolerate slightly cooler temperatures. 

Red Mangroves are distinguished by their aerial prop roots (as shown in the picture below). These are important adaptations for providing gas exchange, anchorage and nutrient adsorption in waterlogged soils. Black mangroves are distinguished by pneumatophores, which are vertical protrusions of the root, involved in gas exchange.  White mangroves can also form pneumatphores in soils with particularly low oxygen levels.  White mangroves have fleshy, oval leaves with rounded ends, which are the same colour both sides.  The leaves of the red and black mangroves both have a pale undersides.  However, black mangrove leave are more shiny, with hairy undersides. 

These thee species are often found in typical zonation patterns, depending on the daily tidal influences (as shown in the picture below). Red mangroves are mainly found closest to the water, flowed by black mangroves and white mangroves. They are found in these zonation patterns due to their different adaptations to soil salinity (salt levels).

Red Mangrove Roots
The importance of Mangroves
Mangroves are important to Florida and the rest of the world because they provide a number of ecosystem services, such as: energy export, carbon storage, coastal protection and fisheries production. Ecosystem services are just the goods and services that an ecosystem can provide, which benefit humans by contributing to their health, social relations and access to basic materials. Mangroves across the world are estimated to be worth $33-57,000 due to the services that they provide (Van Bochove et al. 2014). Mangroves global importance and the fact that they are so beautiful, make them one of my favourite  ecosystems.  
The zonation pattern of the mangrove species found in Florida


Lovers Key Sate Park, Florida
Lovers Key Sate Park, Florida


References 

Van Bochove, J., Sullivan, E., Nakamura, T.  (2014). The Importance of Mangroves to People: A Call to Action. United Nations Environment Programme World Conservation Monitoring Centre: Cambridge. pp.128.


Hutchison, J., Manica, A., Swetnam, R., Balmford, A and Spalding, M. (2014). Predicting Global Patterns in Mangrove Forest Biomass. Conservation Letters, 7, 233–240.