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138 results on '"Mujahid, Aazani"'

3. Towards Automated Biometric Identification of Sea Turtles (Chelonia mydas)

Author

Hipiny, Irwandi, Ujir, Hamimah, Mujahid, Aazani, and Yahya, Nurhartini Kamalia

Subjects
Computer Science - Computer Vision and Pattern Recognition
Abstract

Passive biometric identification enables wildlife monitoring with minimal disturbance. Using a motion-activated camera placed at an elevated position and facing downwards, we collected images of sea turtle carapace, each belonging to one of sixteen Chelonia mydas juveniles. We then learned co-variant and robust image descriptors from these images, enabling indexing and retrieval. In this work, we presented several classification results of sea turtle carapaces using the learned image descriptors. We found that a template-based descriptor, i.e., Histogram of Oriented Gradients (HOG) performed exceedingly better during classification than keypoint-based descriptors. For our dataset, a high-dimensional descriptor is a must due to the minimal gradient and color information inside the carapace images. Using HOG, we obtained an average classification accuracy of 65%., Comment: Published in Journal of ICT Research and Applications, [S.l.], v. 12, n. 3, p. 256-266, dec. 2018

Published
2019
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6. Vertical structure of propagating features

Author

Mujahid, Aazani and Bryden, Harry

Subjects
551.46, GC Oceanography
Abstract

The inter- and intra-annual variability of the western boundary North Atlantic 26.5 ◦N region has been central in the observations of the strength and structure of the Atlantic Meridional Overturning Circulation (AMOC). Interest in this work began when some recent work estimated the inter-annual fluctuations of the AMOC at 26.5 ◦N to be up to 3 Sv, and with a 25% reduction in strength over the last 50 years. There was increased need to understand both the short and long-term changes in the region and the responsible mechanisms for its variability. With the unique use of RAPID-MOC and MOCHA transatlantic mooring array in combination with satellite altimetry and transatlantic hydrographic observations, we find evidence that a significant amount of the variability can be accounted for by various mechanisms on different time-space scales including propagating features. Here we present simultaneous assimilation of surface and sub-surface observations that shows fresh insights into the contribution of the propagating features in the vertical structure of the temporal-spatial evolution in the western boundary 26.5 ◦N Atlantic. There is great prospect in using altimetry observations to reflect and infer the variability throughout the water-column - an effort vital in future interpretations of the AMOC fluctuations using altimetry and numerical models.

Published
2010

8. Spatial-temporal variations in surface ozone over Ushuaia and the Antarctic region: observations from in situ measurements, satellite data, and global models

Author

Nadzir, Mohd Shahrul Mohd, Ashfold, Matthew J., Khan, Md Firoz, Robinson, Andrew D., Bolas, Conor, Latif, Mohd Talib, Wallis, Benjamin M., Mead, Mohammed Iqbal, Hamid, Haris Hafizal Abdul, Harris, Neil R. P., Ramly, Zamzam Tuah Ahmad, Lai, Goh Thian, Liew, Ju Neng, Ahamad, Fatimah, Uning, Royston, Samah, Azizan Abu, Maulud, Khairul Nizam, Suparta, Wayan, Zainudin, Siti Khalijah, Wahab, Muhammad Ikram Abdul, Sahani, Mazrura, Müller, Moritz, Yeok, Foong Swee, Rahman, Nasaruddin Abdul, Mujahid, Aazani, Morris, Kenobi Isima, and Sasso, Nicholas Dal

Published
2017
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18. Nitrous oxide (N2O) and methane (CH4) in rivers and estuaries of northwestern Borneo

Author

Bange, Hermann W., Sim, Chun Hock, Bastian, Daniel, Kallert, Jennifer, Kock, Annette, Mujahid, Aazani, and Müller, Moritz

Subjects
lcsh:Geology, lcsh:QH501-531, lcsh:QH540-549.5, lcsh:QE1-996.5, lcsh:Life, lcsh:Ecology
Abstract

Nitrous oxide (N2O) and methane (CH4) are atmospheric trace gases which play important roles in the climate and atmospheric chemistry of the Earth. However, little is known about their emissions from rivers and estuaries, which seem to contribute significantly to the atmospheric budget of both gases. To this end concentrations of N2O and CH4 were measured in the Rajang, Maludam, Sebuyau and Simunjan rivers draining peatland in northwestern (NW) Borneo during two campaigns in March and September 2017. The Rajang River was additionally sampled in August 2016 and the Samunsam and Sematan rivers were additionally sampled in March 2017. The Maludam, Sebuyau, and Simunjan rivers are typical “blackwater” rivers with very low pH (3.7–7.8), very high dissolved organic carbon (DOC) concentrations (235–4387 mmol L−1) and very low O2 concentrations (31–246 µmol L−1; i.e. 13 %–116 % O2 saturation). The spatial and temporal variability of N2O and CH4 concentrations (saturations) in the six rivers or estuaries was large and ranged from 2.0 nmol L−1 (28 %) to 41.4 nmol L−1 (570 %) and from 2.5 nmol L−1 (106 %) to 1372 nmol L−1 (57 459 %), respectively. We found no overall trends of N2O with O2 or NO3-, NO2- or NH4+, and there were no trends of CH4 with O2 or dissolved nutrients or DOC. N2O concentrations showed a positive linear correlation with rainfall. We conclude, therefore, that rainfall is the main factor determining the riverine N2O concentrations since N2O production or consumption in the blackwater rivers themselves seems to be low because of the low pH. CH4 concentrations were highest at salinity = 0 and most probably result from methanogenesis as part of the decomposition of organic matter under anoxic conditions. CH4 in the concentrations in the blackwater rivers showed an inverse relationship with rainfall. We suggest that CH4 oxidation in combination with an enhanced river flow after the rainfall events might be responsible for the decrease in the CH4 concentrations. The rivers and estuaries studied here were an overall net source of N2O and CH4 to the atmosphere. The total annual N2O and CH4 emissions were 1.09 Gg N2O yr−1 (0.7 Gg N yr−1) and 23.8 Gg CH4 yr−1, respectively. This represents about 0.3 %–0.7 % of the global annual riverine and estuarine N2O emissions and about 0.1 %–1 % of the global riverine and estuarine CH4 emissions. Therefore, we conclude that rivers and estuaries in NW Borneo – despite the fact their water area covers only 0.05 % of the global river/estuarine area – contribute significantly to global riverine and estuarine emissions of N2O and CH4.

Published
2019

19. Enhancing Uptake of Nature-Based Solutions for Informing Coastal Sustainable Development Policy and Planning: A Malaysia Case Study

Author

Chee, Su Yin, primary, Firth, Louise B., additional, Then, Amy Yee-Hui, additional, Yee, Jean Chai, additional, Mujahid, Aazani, additional, Affendi, Yang Amri, additional, Amir, A. Aldrie, additional, Lau, Chai Ming, additional, Ooi, Jillian Lean Sim, additional, Quek, Yew Aun, additional, Tan, Choo Eng, additional, Yap, Tzuen Kiat, additional, Yeap, Chin Aik, additional, and McQuatters-Gollop, Abigail, additional

Published
2021
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22. Spatial and temporal dynamics of suspended sediment concentrations in coastal waters of South China Sea, off Sarawak, Borneo: Ocean colour remote sensing observations and analysis.

Author

Choo, Jenny, Cherukuru, Nagur, Lehmann, Eric, Paget, Matt, Mujahid, Aazani, Martin, Patrick, and Müller, Moritz

Subjects
TERRITORIAL waters, COASTAL sediments, SUSPENDED sediments, COASTAL zone management, WATER quality monitoring, REMOTE sensing
Abstract

High-quality ocean colour observations are increasingly accessible to support various monitoring and research activities for water quality measurements. In this paper, we present a newly developed regional total suspended solids (TSS) empirical model using MODIS-Aqua's Rrs(530) and Rrs(666) reflectance bands to investigate the spatial and temporal variation of TSS dynamics along the southwest coast of Sarawak, Borneo. The performance of this TSS retrieval model was evaluated using error metrics (bias = 1.0, MAE = 1.47, and RMSE = 0.22 in mg/L) with a log10 transformation prior to calculation, as well as a k-fold cross validation technique. The temporally averaged map of TSS distribution, using daily MODIS-Aqua satellite datasets from 2003 until 2019, revealed large TSS plumes detected particularly in the Lupar and Rajang coastal areas on a yearly basis. The average TSS concentration range of 15 - 20 mg/L was estimated at these coastal areas. Moreover, the spatial map of TSS coefficient of variation (CV) indicated strong TSS variability (approximately 90%) in the Samunsam-Sematan coastal areas, which could potentially impact nearby coral reef habitats in this region. Our findings on temporal TSS variation provide further evidence that monsoonal patterns drive the TSS release in these tropical water systems, with distinct and widespread TSS plume variations observed between the northeast and southwest monsoon periods. Map of relative TSS distribution anomalies revealed strong spatial TSS variations in the Samunsam-Sematan coastal areas, while 2010 recorded a major increase (approximately 100%) and widespread TSS distribution with respect to the long-term mean. Furthermore, our findings on the contribution of river discharge to the TSS distribution showed a weak correlation across time at both the Lupar and Rajang river mouth points. The variability of TSS distribution across coastal river points was studied by investigating the variation of TSS pixels at three transect points, stretching from the river mouth into territorial and open water zones, for eight main rivers. Our findings showed a progressively decreasing pattern of nearly 50% in relation to the distance from shore, with exceptions in the northeast regions of the study area. Essentially, our findings demonstrate that the TSS levels at the southwest coast of Sarawak are within local water quality standards, promoting various marine and socio-economic activities. This study presents the first observation of TSS distributions at Sarawak coastal systems with the application of remote sensing technologies, to enhance coastal sediment management strategies for the sustainable use of coastal waters and their resources. [ABSTRACT FROM AUTHOR]

Published
2022
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23. Coral skeletal luminescence records changes in terrigenous dissolved organic matter (tDOM) parameters in tropical coastal waters

Author

Martin, Patrick, primary, Kaushal, Nikita, additional, Tanzil, Jani, additional, Sanwlani, Nivedita, additional, Yang, Liudongqing, additional, Zhou, Yongli, additional, Cherukuru, Nagur, additional, Sahar, Syamil, additional, Müller, Moritz, additional, Mujahid, Aazani, additional, Lee, Jen Nie, additional, and Goodkin, Nathalie, additional

Published
2021
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25. The influence of mesoscale climate drivers on hypoxia in a fjord-like deep coastal inlet and its potential implications regarding climate change and greenhouse gas production: examining a decade of water quality data.

Author

Maxey, Johnathan Daniel, Hartstein, Neil D., Mujahid, Aazani, and Müller, Moritz

Subjects
CLIMATE in greenhouses, GREENHOUSE gases, WATER quality, ANTARCTIC oscillation, CLIMATE change, HYPOXIA (Water), GREENHOUSE gas mitigation
Abstract

Deep coastal inlets are sites of high sedimentation and organic carbon deposition that account for 11% of the world's organic carbon burial. Australasia's mid to high latitude regions have many such systems. It is important to understand the role of climate forcings in influencing hypoxia and organic matter cycling in these systems, but many such systems, especially in Australasia, remain poorly described. We analysed a decade of in-situ water quality data from Macquarie Harbour, Tasmania, a deep coastal inlet with more than 180,000 tons of organic carbon loading per annum. Monthly dissolved oxygen, total Kjeldhal nitrogen, dissolved organic carbon, and dissolved inorganic nitrogen concentrations were significantly affected by rainfall patterns. Increased rainfall was correlated to higher organic carbon and nitrogen loading, lower oxygen concentrations in deep basins, and greater oxygen concentrations in surface waters. Most notably, the Southern Annular Mode (SAM) significantly influenced oxygen distribution in the system. High river flow (associated with low SAM index values) impedes deep water renewal as the primary mechanism driving basin water hypoxia. Climate forecasting predicted increased winter rainfall and decreased summer rainfall, which may further exacerbate hypoxia in this system. Currently, the Harbour basins experience frequent (up to 36% of the time) and prolonged (up to 2 years) oxygen-poor conditions with the potential to promote greenhouse gas (CH4, N2O) production. Increased greenhouse gas production will alter the processing of organic matter entering the system. The increased winter rainfall predicted for the area will potentially increase greenhouse gas emissions due to increased spread and duration of hypoxia in the basins. Further understanding of these systems and how they respond to climate change will improve our estimates of future organic matter cycling (burial vs export) and greenhouse gas production. [ABSTRACT FROM AUTHOR]

Published
2022
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28. Distribution and behaviour of dissolved selenium in tropical peatland-draining rivers and estuaries of Malaysia

Author

Chang, Yan, primary, Müller, Moritz, additional, Wu, Ying, additional, Jiang, Shan, additional, Cao, Wan Wan, additional, Qu, Jian Guo, additional, Ren, Jing Ling, additional, Wang, Xiao Na, additional, Rao, En Ming, additional, Wang, Xiao Lu, additional, Mujahid, Aazani, additional, Muhamad, Mohd Fakharuddin, additional, Sia, Edwin Sien Aun, additional, Jang, Faddrine Holt Ajon, additional, and Zhang, Jing, additional

Published
2020
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31. Distribution and behaviour of dissolved selenium in tropical peatland-draining rivers and estuaries of Malaysia

Author

Chang, Yan, primary, Müller, Moritz, additional, Wu, Ying, additional, Jiang, Shan, additional, Cao, Wan wan, additional, Qu, Jian guo, additional, Ren, Jing ling, additional, Wang, Xiaona, additional, Rao, En ming, additional, Wang, Xiao lu, additional, Mujahid, Aazani, additional, Muhamad, Mohd Fakharuddin, additional, Sia Sien Aun, Edwin, additional, Jang, Faddrine Holt Ajon, additional, and Zhang, Jing, additional

Published
2019
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32. Supplementary material to "Distribution and behaviour of dissolved selenium in tropical peatland-draining rivers and estuaries of Malaysia"

Author

Chang, Yan, primary, Müller, Moritz, additional, Wu, Ying, additional, Jiang, Shan, additional, Cao, Wan wan, additional, Qu, Jian guo, additional, Ren, Jing ling, additional, Wang, Xiaona, additional, Rao, En ming, additional, Wang, Xiao lu, additional, Mujahid, Aazani, additional, Muhamad, Mohd Fakharuddin, additional, Sia Sien Aun, Edwin, additional, Jang, Faddrine Holt Ajon, additional, and Zhang, Jing, additional

Published
2019
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42. Supplementary material to "Dissolved inorganic nitrogen in a tropical estuary at Malaysia: transport and transformation"

Author

Jiang, Shan, primary, Müller, Moritz, additional, Jin, Jie, additional, Wu, Ying, additional, Zhu, Kun, additional, Zhang, Guosen, additional, Mujahid, Aazani, additional, Rixen, Tim, additional, Muhamad, Mohd Fakharuddin, additional, Sia, Edwin Sien Aun, additional, Jang, Faddrine Holt Ajon, additional, and Zhang, Jing, additional

Published
2019
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45. Screening of endophytic fungi for biofuel feedstock production using palm oil mill effluent as a carbon source

Author

Müller Moritz, Edwin Sien Aun Sia, Julie Wei Ming Wong, Jenny Cheng Yi. Choo, Joanne Suan Hui Yeo, Mujahid Aazani, and Wong Changi

Subjects
Biofuel, Bioenergy, Lipid content, Carbon source, Environmental science, Biomass, Biofuel feedstock, Pulp and paper industry, Applied Microbiology and Biotechnology, Palm oil mill effluent, Plant use of endophytic fungi in defense
Abstract

Edwin Sia Sien Aun1, Joanne Yeo Suan Hui1, Julie Wong Wei Ming1, Jenny Choo Cheng Yi1, Changi Wong1, Aazani Mujahid2, Moritz Muller1*

Published
2017

47. Holocene relative sea-level records from coral microatolls in Western Borneo, South China Sea

Author

Majewski, Jędrzej M, primary, Switzer, Adam D, additional, Meltzner, Aron J, additional, Parham, Peter R, additional, Horton, Benjamin P, additional, Bradley, Sarah L, additional, Pile, Jeremy, additional, Chiang, Hong-Wei, additional, Wang, Xianfeng, additional, Ng, Chiew Tyiin, additional, Tanzil, Jani, additional, Müller, Moritz, additional, and Mujahid, Aazani, additional

Published
2018
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48. Denial of long-term issues with agriculture on tropical peatlands will have devastating consequences

Author

Wijedasa, Lahiru S., Jauhiainen, Jyrki, Önönen, Mari K., Lampela, Maija, Vasander, Harri, LeBlanc, Marie-Claire, Evers, Stephanie, Smith, Thomas E.L., Yule, Catherine M., Varkkey, Helena, Lupascu, Massimo, Parish, Faizal, Singleton, Ian, Clements, Gopalasamy R., Aziz, Sheema Abdul, Harrison, Mark E., Cheyne, Susan, Anshari, Gusti Z., Meijaard, Erik, Goldstein, Jenny E., Waldron, Susan, Hergoualc'h, Kristell, Dommain, Rene, Frolking, Steve, Evans, Christopher D., Posa, Mary Rose C., Glaser, Paul H., Suryadiputra, Nyoman, Lubis, Reza, Santika, Truly, Padfield, Rory, Kurnianto, Sofyan, Hadisiswoyo, Panut, Lim, Teck Wyn, Page, Susan E., Gauci, Vincent, van der Meer, Peter J., Buckland, Helen, Garnier, Fabien, Samuel, Marshall K., Choo, Liza Nuriati Lim Kim, O'Reilly, Patrick, Warren, Matthew, Suksuwan, Surin, Sumarga, Elham, Jain, Anuj, Laurance, William F., Couwenberg, John, Joosten, Hans, Vernimmen, Ronald, Hooijer, Aljosja, Malins, Chris, Cochrane, Mark A., Perumal, Balu, Siegert, Florian, Peh, Kelvin S.-H., Comeau, Louis-Pierre, Verchot, Louis, Harvey, Charles F., Cobb, Alex, Jaafar, Zeehan, Wösten, Henk, Manuri, Solichin, Müller, Moritz, Giesen, Wim, Phelps, Jacob, Yong, Ding Li, Silvius, Marcel, Wedeux, Béatrice M.M., Hoyt, Alison, Osaki, Mitsuru, Takashi, Hirano, Takahashi, Hidenori, Kohyama, Takashi S., Haraguchi, Akira, Nugroho, Nunung P., Coomes, David A., Quoi, Le Phat, Dohong, Alue, Gunawan, Haris, Gaveau, David L.A., Langner, Andreas, Lim, Felix K.S., Edwards, David P., Giam, Xingli, van der Werf, Guido, Carmenta, Rachel, Verwer, Caspar C., Gibson, Luke, Grandois, Laure, Graham, Laura Linda Bozena, Regalino, Jhanson, Wich, Serge A., Rieley, Jack, Kettridge, Nicholas, Brown, Chloe, Pirard, Romain, Moore, Sam, Capilla, B. Ripoll, Ballhorn, Uwe, Ho, Hua Chew, Hoscilo, Agata, Lohberger, Sandra, Evans, Theodore A., Yulianti, Nina, Blackham, Grace, Onrizal, Husson, Simon, Murdiyarso, Daniel, Pangala, Sunita, Cole, Lydia E.S., Tacconi, Luca, Segah, Hendrik, Tonoto, Prayoto, Lee, Janice S.H., Schmilewski, Gerald, Wulffraat, Stephan, Putra, Erianto Indra, Cattau, Megan E., Clymo, R.S., Morrison, Ross, Mujahid, Aazani, Miettinen, Jukka, Liew, Soo Chin, Valpola, Samu, Wilson, David, D'Arcy, Laura, Gerding, Michiel, Sundari, Siti, Thornton, Sara A., Kalisz, Barbara, Chapman, Stephen J., Su, Ahmad Suhaizi Mat, Basuki, Imam, Itoh, Masayuki, Traeholt, Carl, Sloan, Sean, Sayok, Alexander K., Andersen, Roxane, Wijedasa, Lahiru S., Jauhiainen, Jyrki, Önönen, Mari K., Lampela, Maija, Vasander, Harri, LeBlanc, Marie-Claire, Evers, Stephanie, Smith, Thomas E.L., Yule, Catherine M., Varkkey, Helena, Lupascu, Massimo, Parish, Faizal, Singleton, Ian, Clements, Gopalasamy R., Aziz, Sheema Abdul, Harrison, Mark E., Cheyne, Susan, Anshari, Gusti Z., Meijaard, Erik, Goldstein, Jenny E., Waldron, Susan, Hergoualc'h, Kristell, Dommain, Rene, Frolking, Steve, Evans, Christopher D., Posa, Mary Rose C., Glaser, Paul H., Suryadiputra, Nyoman, Lubis, Reza, Santika, Truly, Padfield, Rory, Kurnianto, Sofyan, Hadisiswoyo, Panut, Lim, Teck Wyn, Page, Susan E., Gauci, Vincent, van der Meer, Peter J., Buckland, Helen, Garnier, Fabien, Samuel, Marshall K., Choo, Liza Nuriati Lim Kim, O'Reilly, Patrick, Warren, Matthew, Suksuwan, Surin, Sumarga, Elham, Jain, Anuj, Laurance, William F., Couwenberg, John, Joosten, Hans, Vernimmen, Ronald, Hooijer, Aljosja, Malins, Chris, Cochrane, Mark A., Perumal, Balu, Siegert, Florian, Peh, Kelvin S.-H., Comeau, Louis-Pierre, Verchot, Louis, Harvey, Charles F., Cobb, Alex, Jaafar, Zeehan, Wösten, Henk, Manuri, Solichin, Müller, Moritz, Giesen, Wim, Phelps, Jacob, Yong, Ding Li, Silvius, Marcel, Wedeux, Béatrice M.M., Hoyt, Alison, Osaki, Mitsuru, Takashi, Hirano, Takahashi, Hidenori, Kohyama, Takashi S., Haraguchi, Akira, Nugroho, Nunung P., Coomes, David A., Quoi, Le Phat, Dohong, Alue, Gunawan, Haris, Gaveau, David L.A., Langner, Andreas, Lim, Felix K.S., Edwards, David P., Giam, Xingli, van der Werf, Guido, Carmenta, Rachel, Verwer, Caspar C., Gibson, Luke, Grandois, Laure, Graham, Laura Linda Bozena, Regalino, Jhanson, Wich, Serge A., Rieley, Jack, Kettridge, Nicholas, Brown, Chloe, Pirard, Romain, Moore, Sam, Capilla, B. Ripoll, Ballhorn, Uwe, Ho, Hua Chew, Hoscilo, Agata, Lohberger, Sandra, Evans, Theodore A., Yulianti, Nina, Blackham, Grace, Onrizal, Husson, Simon, Murdiyarso, Daniel, Pangala, Sunita, Cole, Lydia E.S., Tacconi, Luca, Segah, Hendrik, Tonoto, Prayoto, Lee, Janice S.H., Schmilewski, Gerald, Wulffraat, Stephan, Putra, Erianto Indra, Cattau, Megan E., Clymo, R.S., Morrison, Ross, Mujahid, Aazani, Miettinen, Jukka, Liew, Soo Chin, Valpola, Samu, Wilson, David, D'Arcy, Laura, Gerding, Michiel, Sundari, Siti, Thornton, Sara A., Kalisz, Barbara, Chapman, Stephen J., Su, Ahmad Suhaizi Mat, Basuki, Imam, Itoh, Masayuki, Traeholt, Carl, Sloan, Sean, Sayok, Alexander K., and Andersen, Roxane

Abstract

Letter to the Editor.

Published
2017

49. Denial of long-term issues with agriculture on tropical peatlands will have devastating consequences

Author

Singapore-MIT Alliance in Research and Technology (SMART), Parsons Laboratory for Environmental Science and Engineering (Massachusetts Institute of Technology), Harvey, Charles F, Hoyt, Alison May, Cobb, Alexander R., Wijedasa, Lahiru S., Jauhiainen, Jyrki, Könönen, Mari, Lampela, Maija, Vasander, Harri, Leblanc, Marie-Claire, Evers, Stephanie, Smith, E. L. Thomas, Yule, Catherine M., Varkkey, Helena, Lupascu, Massimo, Parish, Faizal, Singleton, Ian, Clements, Gopalasamy R., Aziz, Sheema Abdul, Harrison, Mark E., Cheyne, Susan, Anshari, Gusti Z., Meijaard, Erik, Goldstein, Jenny E., Waldron, Susan, Hergoualc'h, Kristell, Dommain, Rene, Frolking, Steve, Evans, Christopher D., Posa, Mary Rose C., Glaser, Paul H., Suryadiputra, Nyoman, Lubis, Reza, Santika, Truly, Padfield, Rory, Kurnianto, Sofyan, Hadisiswoyo, Panut, Lim, Teck Wyn, Page, Susan E., Gauci, Vincent, Van Der Meer, Peter J., Buckland, Helen, Garnier, Fabien, Samuel, Marshall K., Choo, Liza Nuriati Lim Kim, O'Reilly, Patrick, Warren, Matthew, Suksuwan, Surin, Sumarga, Elham, Jain, Anuj, Laurance, William F., Couwenberg, John, Joosten, Hans, Vernimmen, Ronald, Hooijer, Aljosja, Malins, Chris, Cochrane, Mark A., Perumal, Balu, Siegert, Florian, Peh, Kelvin S.-H., Comeau, Louis-Pierre, Verchot, Louis, Jaafar, Zeehan, Wösten, Henk, Manuri, Solichin, Müller, Moritz, Giesen, Wim, Phelps, Jacob, Yong, Ding Li, Silvius, Marcel, Wedeux, Béatrice M. M., Osaki, Mitsuru, Hirano, Takashi, Takahashi, Hidenori, Kohyama, Takashi S., Haraguchi, Akira, Nugroho, Nunung P., Coomes, David A., Quoi, Le Phat, Dohong, Alue, Gunawan, Haris, Gaveau, David L. A., Langner, Andreas, Lim, Felix K. S., Edwards, David P., Giam, Xingli, Van Der Werf, Guido, Carmenta, Rachel, Verwer, Caspar C., Gibson, Luke, Gandois, Laure, Graham, Laura Linda Bozena, Regalino, Jhanson, Wich, Serge A., Rieley, Jack, Kettridge, Nicholas, Brown, Chloe, Pirard, Romain, Capilla, B. Ripoll, Ballhorn, Uwe, Ho, Hua Chew, Hoscilo, Agata, Lohberger, Sandra, Evans, Theodore A., Yulianti, Nina, Blackham, Grace, Onrizal, Grace, Husson, Simon, Murdiyarso, Daniel, Pangala, Sunita, Cole, Lydia E. S., Tacconi, Luca, Segah, Hendrik, Tonoto, Prayoto, Lee, Janice S. H., Schmilewski, Gerald, Wulffraat, Stephan, Putra, Erianto Indra, Cattau, Megan E., Clymo, R. S., Morrison, Ross, Mujahid, Aazani, Miettinen, Jukka, Liew, Soo Chin, Valpola, Samu, Wilson, David, D'Arcy, Laura, Gerding, Michiel, Sundari, Siti, Thornton, Sara A., Kalisz, Barbara, Chapman, Stephen J., Su, Ahmad Suhaizi Mat, Basuki, Imam, Itoh, Masayuki, Traeholt, Carl, Sloan, Sean, Sayok, Alexander K., Andersen, Roxane, Moore, Sam, S.B. Massachusetts Institute of Technology, Singapore-MIT Alliance in Research and Technology (SMART), Parsons Laboratory for Environmental Science and Engineering (Massachusetts Institute of Technology), Harvey, Charles F, Hoyt, Alison May, Cobb, Alexander R., Wijedasa, Lahiru S., Jauhiainen, Jyrki, Könönen, Mari, Lampela, Maija, Vasander, Harri, Leblanc, Marie-Claire, Evers, Stephanie, Smith, E. L. Thomas, Yule, Catherine M., Varkkey, Helena, Lupascu, Massimo, Parish, Faizal, Singleton, Ian, Clements, Gopalasamy R., Aziz, Sheema Abdul, Harrison, Mark E., Cheyne, Susan, Anshari, Gusti Z., Meijaard, Erik, Goldstein, Jenny E., Waldron, Susan, Hergoualc'h, Kristell, Dommain, Rene, Frolking, Steve, Evans, Christopher D., Posa, Mary Rose C., Glaser, Paul H., Suryadiputra, Nyoman, Lubis, Reza, Santika, Truly, Padfield, Rory, Kurnianto, Sofyan, Hadisiswoyo, Panut, Lim, Teck Wyn, Page, Susan E., Gauci, Vincent, Van Der Meer, Peter J., Buckland, Helen, Garnier, Fabien, Samuel, Marshall K., Choo, Liza Nuriati Lim Kim, O'Reilly, Patrick, Warren, Matthew, Suksuwan, Surin, Sumarga, Elham, Jain, Anuj, Laurance, William F., Couwenberg, John, Joosten, Hans, Vernimmen, Ronald, Hooijer, Aljosja, Malins, Chris, Cochrane, Mark A., Perumal, Balu, Siegert, Florian, Peh, Kelvin S.-H., Comeau, Louis-Pierre, Verchot, Louis, Jaafar, Zeehan, Wösten, Henk, Manuri, Solichin, Müller, Moritz, Giesen, Wim, Phelps, Jacob, Yong, Ding Li, Silvius, Marcel, Wedeux, Béatrice M. M., Osaki, Mitsuru, Hirano, Takashi, Takahashi, Hidenori, Kohyama, Takashi S., Haraguchi, Akira, Nugroho, Nunung P., Coomes, David A., Quoi, Le Phat, Dohong, Alue, Gunawan, Haris, Gaveau, David L. A., Langner, Andreas, Lim, Felix K. S., Edwards, David P., Giam, Xingli, Van Der Werf, Guido, Carmenta, Rachel, Verwer, Caspar C., Gibson, Luke, Gandois, Laure, Graham, Laura Linda Bozena, Regalino, Jhanson, Wich, Serge A., Rieley, Jack, Kettridge, Nicholas, Brown, Chloe, Pirard, Romain, Capilla, B. Ripoll, Ballhorn, Uwe, Ho, Hua Chew, Hoscilo, Agata, Lohberger, Sandra, Evans, Theodore A., Yulianti, Nina, Blackham, Grace, Onrizal, Grace, Husson, Simon, Murdiyarso, Daniel, Pangala, Sunita, Cole, Lydia E. S., Tacconi, Luca, Segah, Hendrik, Tonoto, Prayoto, Lee, Janice S. H., Schmilewski, Gerald, Wulffraat, Stephan, Putra, Erianto Indra, Cattau, Megan E., Clymo, R. 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Published
2017

50. Distribution and behaviour of dissolved selenium in tropical peatland-draining rivers and estuaries of Malaysia.

Author

Yan Chang, Müller, Moritz, Ying Wu, Shan Jiang, Wan wan Cao, Jian guo Qu, Jing ling Ren, Xiaona Wang, En ming Rao, Xiao lu Wang, Mujahid, Aazani, Muhamad, Mohd Fakharuddin, Aun, Edwin Sia Sien, Jang, Faddrine Holt Ajon, and Jing Zhang

Subjects
RIVERS, TERRITORIAL waters, PEAT soils, SELENIUM, ESTUARIES, BIOGEOCHEMICAL cycles, HUMUS, DISSOLVED organic matter
Abstract

Selenium (Se) is an essential micronutrient for many organisms. Despite its importance, our current knowledge of the biogeochemical cycling of dissolved Se in tropical estuaries is limited, especially in Southeast Asia. To gain insights into Se cycling in tropical peat-draining rivers and estuaries, samples were collected from the Rajang, Maludam, Sebuyau, Simunjan, Sematan, Samunsam, and Lunda rivers and estuaries in western Sarawak, Malaysia, in March and September 2017 and analysed for various forms of Se (dissolved inorganic and organic). Mean total dissolved Se (TDSe), dissolved inorganic Se (DISe), and dissolved organic Se concentrations (DOSe) were 2.2 nmol L-1 (range: 0.7 to 5.7 nmol L-1), 0.18 nmol L-1 (range: less than the detection limit to 0.47 nmol L-1), and 2.0 nmol L-1 (range: 0.42 to 5.7 nmol L-1), respectively. In acidic, low-oxygen, organic-rich blackwater (peatland-draining) rivers, the concentrations of DISe were extremely low, whereas those of DOSe were high. In rivers and estuaries that drained peatland, DOSe / TDSe ratios ranged from 0.67 to 0.99, showing that DOSe dominated. The positive relationship between DISe and salinity and the negative relationship between DOSe and salinity indicate marine and terrestrial origins of DISe and DOSe, respectively. The positive correlations of DOSe with the humification index and humic-like chromophoric dissolved organic matter components in freshwater river reaches suggest that peat soils are probably the main source of DOSe. Discharges of water enriched with DOSe fractions associated with peatland-derived high-molecular-weight, high-aromaticity dissolved organic matter discharged from estuaries may promote productivity in the adjoining oligotrophic coastal waters. The results of this study suggest that the impacts of Se discharges on coastal ecosystems should be evaluated in the future. [ABSTRACT FROM AUTHOR]

Published
2019
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