INOS UMT | Institut Oseanografi dan Sekitaran » Spatial and Seasonal Variations of Organic Carbon-Based Nutrients in Setiu Wetland, Malaysia
14
JAN
2018

Spatial and Seasonal Variations of Organic Carbon-Based Nutrients in Setiu Wetland, Malaysia

Spatial and Seasonal Variations of Organic Carbon-Based
Nutrients in Setiu Wetland, Malaysia
(Variasi Bermusim dan Reruang Nutrien Berasaskan Karbon di Tanah Bencah Setiu, Malaysia)
SUHAIMI SURATMAN*, NUR HAYATI CHE ZAN, AZYYATI ABDUL AZIZ & NORHAYATI MOHD TAHIR

ABSTRACT
The aim of this study was to assess spatial and seasonal variations of dissolved and particulate organic carbon (DOC and POC, respectively) in the Setiu Wetland, which is located in the southern region of the South China Sea coastal area. Surface water samples were collected monthly from October 2009-September 2010. In addition, the concentration of chlorophyll-a was determined. The DOC and POC mean concentration varied between 80-340 µM and 60-115 µM, respectively. The results showed that the concentrations of these parameters were mainly influenced by human activities and season. Higher concentrations of DOC (150-340 µM) and POC (75-115 µM) were found at stations near the populated
area, aquaculture and palm oil plantation. In addition, higher concentrations of DOC (200-275 µM) and POC (105-150µM) were also recorded during the monsoon season due to runoff from terrestrial sources and resuspension from bottom sediments. No significant correlation between the low molecular weight (LMW) fractions of DOC and chlorophyll-a (R2=0.0096, p>0.05) further supports the hypothesis that phytoplankton not playing key role in regulating the organic carbon distribution. Higher percentage of LMW DOC in monsoon season suggesting possible input of this fraction from land runoff to the wetland area.

Keywords: Dissolved organic carbon; particulate organic carbon; Setiu Wetland (Malaysia); spatial and seasonal variations, surface water

ABSTRAK
Kajian ini dijalankan untuk menilai variasi bermusim dan reruang karbon organik terlarut dan partikulat (masing-masing DOC dan POC) di Tanah Bencah Setiu, yang terletak di kawasan perairan selatan Laut China Selatan. Sampel air permukaan dikumpulkan secara bulanan dari Oktober 2009-September 2010. Sebagai tambahan, kepekatan klorofil-a juga ditentukan. Purata kepekatan DOC dan POC masing-masing berubah antara 80-340 µM dan 60-115 µM. Keputusan kajian menunjukkan kepekatan parameter ini dipengaruhi terutamanya oleh aktiviti manusia dan musim. Kepekatan DOC (150-340 µM) dan POC (75-115 µM) yang tinggi direkodkan di stesen yang berhampiran dengan kawasan yang ramai penduduk, akuakultur dan perladangan kelapa sawit. Tambahan lagi, kepekatan DOC (200-275 µM) dan POC (105-150 µM) adalah tinggi semasa musim monsun disebabkan oleh larutlesap daripada sumber daratan dan ampaian dari sedimen dasar. Tidak terdapat korelasi signifikan antara fraksi DOC yang mempunyai berat molekul rendah (LMW) dan klorofil-a (R2=0.0096, p>0.05) yang seterusnya menyokong hipotesis bahawa fitoplankton tidak memainkan perananpenting dalam mengawal taburan karbon organik. Peratusan LMW DOC yang tinggi semasa musim monsun mencadangkan
kemungkinan input fraksi ini dari larutlesap daratan ke kawasan tanah bencah.

Kata kunci: Air permukaan; karbon organik partikulat; karbon organik terlarut; Tanah Bencah Setiu (Malaysia); variasi
bermusim dan reruang

http://www.ukm.my/jsm/pdf_files/SM-PDF-46-6-2017/04%20Suhaimi.pdf