Nitrate sources and processes in the surface water of a tropical reservoir by stable isotopes and mixing model
Nitrate sources and processes in the surface water of a tropical reservoir by stable isotopes and mixing model
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DOI：
10.1016/j.scitotenv.2019.134517
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发表时间：
2020-01-15
影响因子：
9.8
通讯作者：
Li, Si-Liang
中科院分区：
文献类型：
--
作者：
Fadhullah, Widad;Yaccob, Nur Syahirah;Li, Si-Liang
硝酸盐是与沉积作用相关的主要营养盐之一，是水库系统中富营养化的燃料。在这项研究中，从武吉美拉水库（BMR）的水样进行了分析，结合水化学，水稳定同位素（δ H-2-H2O和δ O-18-H2O）和硝酸盐稳定同位素（δ N-15-NO3和δ O-18-NO3）。目的是评估马来西亚最古老的人工水库BMR中的硝酸盐来源和过程。河流和水库水样中的三角洲N-15-NO3值在+0.4至+14.9ppm之间，而三角洲O-18-NO3值分别在-0.01至+39.4ppm之间。三角洲N-15-NO3和三角洲O-18-NO3的双重图反映了大气沉降（AD）输入、肥料/雨水中的铵、土壤氮以及粪便和污水（MS）作为BMR地表水中硝酸盐来源的混合源。硝酸盐稳定同位素表明，BMR经历了硝化和混合等过程。反硝化作用和同化作用在系统中并不普遍。贝叶斯混合模型突出了MS源在系统中的主导地位，而AD在两个季节的水库比在河流中贡献更大的比例。三角洲C-13，三角洲N-15，和C：N比的使用，使陆地来源的沉积物中的有机物质的识别，提高了对沉积与营养物质的理解以前在BMR报告。总的来说，在水库灌溉、龙鱼养殖和生活供水的管理决策中，应考虑硝酸盐的来源和过程。(C)2019爱思唯尔B. V.保留所有权利。
Nitrate is one of the primary nutrients associated with sedimentation and fuels eutrophication in reservoir systems. In this study, water samples from Bukit Merah Reservoir (BMR) were analysed using a combination of water chemistry, water stable isotopes (delta H-2-H2O and delta O-18-H2O) and nitrate stable isotopes (delta N-15-NO3 and delta O-18-NO3). The objective was to evaluate nitrate sources and processes in BMR, the oldest man-made reservoir in Malaysia. The delta N-15-NO3 values in the river and reservoir water samples were in the range +0.4 to +14.9 parts per thousand while the values of delta O-18-NO3 were between -0.01 and +39.4 parts per thousand, respectively. The dual plots of delta N-15-NO3 and delta O-18-NO3 reflected mixing sources from atmospheric deposition (AD) input, ammonium in fertilizer/rain, soil nitrogen, and manure and sewage (MS) as the sources of nitrate in the surface water of BMR. Nitrate stable isotopes suggested that BMR undergoes processes such as nitrification and mixing. Denitrification and assimilation were not prevalent in the system. The Bayesian mixing model highlighted the dominance of MS sources in the system while AD contributed more proportion in the reservoir during both seasons than in the river. The use of delta C-13, delta N-15, and C:N ratios enabled the identification of terrestrial sources of the organic matter in the sediment, enhancing the understanding of sedimentation associated with nutrients previously reported in BMR. Overall, the nitrate sources and processes should be considered in decision-making in the management of the reservoir for irrigation, Arowana fish culture and domestic water supply. (C) 2019 Elsevier B.V. All rights reserved.