Sunday, 23 August 2015

Fieldwork to investigate human induced changes on important Asian wetlands…by Melanie Leng

Suzanne McGowan, Melanie Leng and Ginni Pannizo (left
to right taking cores of sediment from Tasik Chini. 
Exponential population growth, urban expansion and climate change are changing the quality of freshwaters around the World. In countries such as Malaysia which aims to become a "fully developed" nation by 2020 rapid deforestation, urban development and resource exploitation have put drainage basins under unprecedented pressures. A team from the Centre for Environmental Geochemistry (BGS and the University of Nottingham) went on a site investigation to look at one of Malaysia's premier wetlands, the famous Tasik Chini site in central Pahang to investigate the current and past water quality status using information preserved in the sediments that have accumulated on the bottom of the lake. Here Melanie Leng tells us more… 

The tropical lowland lake Tasik Chini in Malaysia is currently undergoing rapid ecological change which threatens the livelihoods of populations living around the lake as well as the economy of the region (ie agriculture, fisheries, tourism, industry). Tasik Chini is of national and international importance, having been awarded protected status by UNESCO's Man and Biosphere Programme. Immediate threats to the lakes include pollution (from sewage, toxins from catchment mining, acid rain from coal burning), land development (soil erosion and rapid sedimentation, fertilizer runoff from oil palm), invasive species (Cabomba caroliniana in place of the native lotus), hydrological modification (artificial raising of the water level which has altered the natural flood pulse) and climate change. Effective management of these ecosystems is required before they are irreversibly damaged. This new research project between the BGS and the University of Nottingham (Malaysia and UK campuses) aims to provide the first palaeolimnological (lake sediment core) study of continuous human and environmental change on the Peninsular Malaysia spanning the last few centuries. 

Deforestation is a big problem in the catchment due to
mining and palm oil plantations. 
This month I was part of a team that went to Taski Chini to extract sediment cores as part of a reconnaissance study. The sediments record changes through time (the oldest sediments being at the bottom of the cores and becoming younger upwards). We will be analysing the sediments for geochemical and biological parameters. These parameters will tell us about changing water quality both now and in the past before many of the pressures were placed on the system (ie sedimentation rate, algal biodiversity, primary production, toxic algal species, heavy metal and organic pollutants). The field work was a success with us taking 7 sediment cores from across the lake (each core was approximately 1m long and represents sediment accumulation over the last few hundred years). The sediments were sampled on site and are now awaiting analysis. Overall we hope to show the ecological status of the lake prior to human intervention and show the recent anthropogenic changes to the lake ecosystem with a view of future mitigation.  

Tasik Chini panorama from the Tasik Chini Resort. 
This fieldwork was headed by Dr Suzanne McGowan, Head of School of Geography, University of Nottingham Malaysia Campus, with strong collaborative links with Prof Dato' Dr Mushrifah Idris (Director of the Tasik Chini Research Centre) and Mr Muhammad Shafiq Bin Ruslan in Malaysia. The project team includes Dr Keely Mills (BGS), Prof Sarah Metcalfe (UoN), and Dr Ginnie Panizzo (UoN). Much of the analytical work will be done within the Centre for Environmental Geochemistry, UoN-BGS. Many thanks to Shafiq's students who helped with the fieldwork. This project is being funded by the University of Nottingham.

Thanks to the support from Shafiq (left), and his students Minisha, Noor
(on the right) and Yasmin from the Tasik Chini Research Centre. 
Melanie Leng is the Director of the Centre for Environmental Geochemistry and Science Director for the Stable Isotope Facility at the BGS. Follow Mel on Twitter @MelJLeng





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