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In this work, the spatial and temporal sensitivities of the significant wave height (SWH) to ten key parameters in the SWAN model under typhoon conditions are assessed through comprehensive observations at four buoy stations along the eastern coast of China. Experiments were conducted using wind forcing based on Typhoon Chan-hom, which made landfall at Zhujiajian island in 2015. Assessments included wind input and whitecapping, bottom friction, depth-induced wave breaking, and nonlinear quadruplet wave interactions parameterizations. The results show that in shallow water whose depth is less than the threshold depth, depth-induced wave breaking dominates the SWH, and the SWH is most sensitive to the parameter gamma (the ratio of maximum individual wave height to depth) of depth-induced wave breaking. However, beyond a certain threshold depth, the sensitivity of the SWH to depth-induced wave breaking begins to reduce. This threshold depth depends on sea states and ranges from 5 m to 30 m. In deep water, where the water depth is more than the threshold depth, SWH is primarily influenced by wind input and whitecapping. In general, the sensitivity is greater in coastal areas than in the open ocean. With regard to sea state, the higher the sea state, the deeper the threshold depth. The four different numerical procedures of four-wave interactions (so-called quadruplets) mainly affect the distribution of wave energy, not the SWH. In addition, the SWH is most sensitive to the drag coefficient, and bigger wave implies greater sensitivity. The study of spatial and temporal sensitivities of key parameters is of great significance for further application of the SWAN model and wave simulations, especially typhoon wave simulations. • In shallow water, depth-induced wave breaking dominates the significant wave height (SWH). • In deep water whose depth is more than the threshold depth, SWH is primarily influenced by wind input and whitecapping. • This threshold depth depends on sea states and ranges from 5 m to 30 m. • The higher the sea state, the deeper the threshold depth. [ABSTRACT FROM AUTHOR]

The unreasonable use of antibiotics and the transmission of antibiotic resistance genes (ARGs) induced by antibiotics have led to a large number of ARGs entered the water environment, which seriously threatened human health and environmental safety. The estuarine aquatic environment connects with inland rivers and sea and is frequently influenced by human activities. This study aims to reveal the occurrences and abundances of ARGs and bacterial community composition by high-throughput quantitative PCR including 296 primers and high-throughput sequencing in the tide rising and ebbing of surface water in the Yongjiang Estuary, China. The results showed that there were a large number of ARGs and mobile genetic elements (MGEs) detected in the rising tide and ebb tide water bodies. The numbers of detected ARGs in each sample at rising and ebb tide ranged from 16 to 77 and 61 to 88, respectively, and the absolute abundance ranges were 1.69 × 104–1.69 × 109 copies/L and 3.18 × 103–2.57 × 109 copies/L, respectively. Obvious tidal distribution characteristics of ARGs were showed. Most of ARGs conferred resistance to multidrug, aminoglycosides and sulfanilamides. Proteobacteria, Actinobacteria and Bacteroidetes were the dominantly bacterial phylum in the Yongjiang Estuary. Network analysis results indicated that multi-genera were identified as possible ARGs hosts, and they carried more than two types of ARGs genes. Partial least squares path modeling further revealed that MGEs and bacterial community composition were the most important driving factors. The results of the study can provide the corresponding scientific basis for the diffusion and control of ARGs in estuaries. • Tides had influences on the abundance of ARGs. • The abundance of multidrug resistance genes was the highest. • ARGs might have more than one potential hosts. • MGEs and bacterial community composition were the key factors affecting the spread of ARGs. [ABSTRACT FROM AUTHOR]