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Riverine inputs of total organic carbon and suspended particulate matter from the Pearl River Delta to the coastal ocean off South China 总被引：4，自引：0，他引：4
A total of 1008 samples were collected from the eight major riverine runoff outlets in the Pearl River Delta (PRD) during 2005-2006 to estimate the fluxes of total organic carbon (TOC) to the coastal ocean off South China. The average dissolved organic carbon (DOC) concentration was 1.67 mg/L with a range of 1.38-2.13 mg/L. Concentrations of particulate organic carbon (POC) ranged from 2.66-4.12% of total suspended particulate matter (SPM). The fluxes of TOC and SPM from the PRD via the eight outlets were 9.2 x 10(5) and 2.5 x 10(7)tons/yr, respectively. Temporal variations in POC and DOC were observed at all outlets due to the large variability in runoff levels because of the seasonality of rainfall, and the riverine discharge amount was an important factor controlling TOC flux. The net contribution of organic carbon from the PRD to the coastal ocean represented approximately 0.1-0.2% of total organic carbon transported by rivers worldwide. 相似文献
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Occurrence and phase distribution of polycyclic aromatic hydrocarbons in riverine runoff of the Pearl River Delta, China 总被引：6，自引：0，他引：6
The occurrence and phase distribution of polycyclic aromatic hydrocarbons (PAHs) in waters at the eight riverine outlets of the Pearl River Delta (China) were examined based on a monthly sampling program from March 2005 to February 2006. The total concentrations of PAHs in the aqueous phase and suspended particulate matter (SPM) combined ranged from 55.5 to 522 ng/L, at the mid level of the global values in rivers and estuaries. No clear temporal and spatial trends of PAH concentrations were found. However, the concentrations of PAHs associated with SPM coincided with the monthly precipitation of Guangzhou, indicating the importance of atmospheric deposition. The PAHs found in the region were likely derived from a combined pyrolytic and petrogenic origin, as suggested by the molecular indices of PAHs. Normalized partition coefficient (K(oc)) between water and SPM was correlated with octanol-water partition coefficient (K(ow)) to understand the environmental behavior of PAHs. 相似文献
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测程是全站仪重要技术指标之一,本文从相位式测距仪的测程公式出发,探讨了在短基线或短距离上进行测程检测的原理和方法,为中、长程全站仪的测程检验提供了可能性。这种检验方法是在短基线或短距离上用改变反射镜有效面积进行测程实验,操作简单方便,结果可靠。利用本文研究成果可以算出任意棱镜组合所对应的测程,这样可更合理地使用棱镜,以便减少仪器幅相误差的影响,提高测程精度。 相似文献
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核电工程控制网的布设及其特点 总被引：1，自引：0，他引：1
从实际出发,总结出现有核电工程控制网的布设状况、实测精度及其特点,提出一些作者的见解。 相似文献
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对俯冲带地震的研究将提供什么海底资料？ＸａｖｉｅｒＬｅＰｉｃｈｏｎ等本文第一作者１９９５年１—５月在海洋研究所逗留期间，正值海底研究不断取得进展，其中包括研究其陆上和海域的区域环境方面的Ｋａｉｋｏ—Ｔｏｋａｉ项目，这些研究内容已写成了数篇论文，第一篇... 相似文献
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本文对光电测距边计算水平距离的几个公式进行了分析,并就计算结果所在的高程面进行了讨论,给出了归化到椭球体面上的统一公式. 相似文献