Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qing Dao 266100, China.
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qing Dao 266100, China.
Mar Pollut Bull. 2020 Mar;152:110898. doi: 10.1016/j.marpolbul.2020.110898. Epub 2020 Jan 17.
With the increase in human activities, dissolved organic nitrogen (DON) has been the major nitrogen pool, which might impact on eutrophication of coastal water. We studied the bioavailability of different molecular size DON from the major sources of agricultural, domestic, industrial, and urban non-point source, respectively, in Jiaozhou bay, China. By clarifying the relationship between the source and molecular size, the bioavailability of terrestrial DON can be further understood based on the aspects of bioavailability proportion (BDON%) and kinetics with the help of ultraviolet radiation. The bioavailability proportion of high molecular size DON (HDON; >1000 Da) was higher than that of low molecular size DON (LDON; <1000 Da), with values of 58.0% to 35.1% for the HDON and values of 47.2% to 29.5% for the LDON, respectively. There were significant differences in the degradation rate constants (p < 0.05), which varied from 0.30 to 0.67 d for HDON and from 0.13 to 0.75 d for LDON. The SUVA values were significantly and negatively correlated with the bioavailabilities of DON, which can reflect to some extent the structure and molecular size. In order to study the influences of the different terrestrial DON inputs on the eutrophication of Jiaozhou bay, a modified 3D coupled biogeochemical model was used based on the survey data in August 2012. Two scenarios of DON loads from Haibo river and Dagu river were modeled. The impact on eutrophication of Jiaozhou bay is higher for the agricultural source of DON from Dagu river than for the domestic source from Haibo river.
随着人类活动的增加，溶解有机氮（DON）已成为主要的氮库，这可能会影响沿海水域的富营养化。我们分别研究了来自农业、家庭、工业和城市非点源的主要来源的不同分子大小 DON 的生物可利用性。通过阐明来源和分子大小之间的关系，借助紫外线辐射，可以从生物可利用性比例（BDON%）和动力学方面进一步了解陆地 DON 的生物可利用性。高分子大小 DON（HDON；>1000 Da）的生物可利用性比例高于低分子大小 DON（LDON；<1000 Da），HDON 的值为 58.0%至 35.1%，LDON 的值为 47.2%至 29.5%。降解率常数（p < 0.05）存在显著差异，HDON 的范围为 0.30 至 0.67 d，LDON 的范围为 0.13 至 0.75 d。SUVA 值与 DON 的生物可利用性呈显著负相关，可以在一定程度上反映 DON 的结构和分子大小。为了研究不同陆地 DON 输入对胶州湾富营养化的影响，根据 2012 年 8 月的调查数据，使用了改进的三维耦合生物地球化学模型。模拟了来自海河和大沽河的 DON 负荷的两个场景。大沽河农业源 DON 对胶州湾富营养化的影响高于海河家庭源 DON。
