Tuesday, 31 May 2016

More on our project investigating human impact on Malaysian wetlands...this time by Masters student Charly Briddon

Charly Briddon on Tasik Chini undertaking a diatom habitat
survey.
Hi, my name is Charly Briddon and I am Keele University student currently undertaking research for my MSc in Geoscience. For my international placement I have joined a collaborative project within the Centre for Environmental Geochemistry (a collaboration between the University of Nottingham and the British Geological Survey) involving supervisors at Keele University (Dr Antonia Law), University of Nottingham (Dr Suzanne McGowan) and the British Geological Survey (Dr Keely Mills). This has given me the opportunity to spend six months at the University of Nottingham Campus in Malaysia investigating how human activities within the lake catchment of a really special wetland system (Tasik Chini) has changed the lake ecology over time…

The diverse plant communities of Tasik Chini provide a range
of different habitats for microscopic diatoms. 
The Tasik Chini research project has been introduced in previous blogs by Prof Melanie Leng and Dr Stefan Engels. My role in the project is to primarily use diatoms to reconstruct past conditions in the lake over the past hundred years or so.  I have been analysing sediment cores collected from the various basins in the lake during the summer of 2015.  Fossil diatoms (types of algae with silica shells) can provide information about water quality, water level change and shifts in lake habitat structure. However, there is not a lot of previous diatom work on these types of shallow tropical wetlands and so I am supplementing this work by investigating where the diatoms are growing today. In April 2016 I collected diatom samples from plants, muds and waters in the lake to determine whether there are habitat affinities that I can use to interpret the core data.

The second part of my project is to try to characterise the organic material in the lake sediments. I started off by conducting loss-on-ignition analysis, which is literally burning the mud to give an estimate of the proportion of organic versus minerogenic material. I am also developing a technique to look at the fluorescence characteristics of the porewaters. We are using a UV visible spectrometer which provides 3-dimensional data on excitation and emission to provide information on where the organic matter in the sediments comes from- for example is it from soil erosion or from algal blooms in the lake.  This technique is quite novel and I am looking forward to using this piece of equipment which is brand new to the university, this part of my project is being supervised by Dr Shafi Tareq from the School of Biosciences in Malaysia.
Charly Briddon, Shafi Tareq and Suzanne McGowan
undertaking porewater flourescence analysis. 

Initial results from the diatom and organic analysis indicate that changes observed in the sediments appear to correspond with changes in human activities in the lake catchment, possibly associated with deforestation in the 1940s and the building of the dam around 1995. We also think that there might be evidence for acidification from atmospheric contamination in recent decades. However, we are waiting for dating of the core to be completed before these results can be interpreted with more certainty. I am looking forward to completing my laboratory work in mid-June when analysis of the results obtained and write up of my dissertation can start in earnest.

Charly Briddon is a Masters student at Keele University undertaking her project within the Centre for Environmental Geochemistry at the University of Nottingham and the British Geological Survey 







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