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This study examines whether there exist significant differences in tropical cyclone (TC) landfall between central Pacific (CP) El Niño, eastern Pacific (EP) El Niño, and La Niña during the peak TC season (June-October) and how and to what extent CP El Niño influences TC landfall over East Asia for the period 1961-2009. The peak TC season is subdivided into summer [June-August (JJA)] and autumn [September-October (SO)]. The results are summarized as follows: (i) during the summer of CP El Niño years, TCs are more likely to make landfall over East Asia because of a strong easterly steering flow anomaly induced by the westward shift of the subtropical high and northward-shifted TC genesis. In particular, TCs have a greater probability of making landfall over Japan and Korea during the summer of CP El Niño years. (ii) In the autumn of CP El Niño years, TC landfall in most areas of East Asia, especially Indochina, the Malay Peninsula, and the Philippines, is likely to be suppressed because the large-scale circulation resembles that of EP El Niño years. (iii) During the whole peak TC season [June-October (JJASO)] of CP El Niño years, TCs are more likely to make landfall over Japan and Korea. TC landfall in East Asia as a whole has an insignificant association with CP El Niño during the peak TC season. In addition, more (less) TCs are likely to make landfall in China, Indochina, the Malay Peninsula, and the Philippines during the peak TC season of La Niña (EP El Niño) years. [ABSTRACT FROM AUTHOR]

The Tanlu Fault Zone in eastern China stretches more than 2,400 km and is a significant, active, feature in the tectonics of East Asia. Here, we show the results of local earthquake travel‐time tomographical approach based on a comprehensive and systematic set of seismic data collected from 2008 to 2018 along the Central South Segment of the Tanlu Fault Zone. According to the model, the uppermost 0–10 km of the crust shows a close relationship between seismic velocity and the lithological properties of surface geological units. The middle crust at 10–20 km depths exhibits a strong connection between its high‐low velocity transitions and sites of augmented seismic activity. The top mantle at 34 km depths has lower velocities in the western region in comparison to the east, implying that the seismic Moho is deeper in the western area. These characteristics may reflect spatial variations in the destruction of the North China Craton. [ABSTRACT FROM AUTHOR]

• The mycelium of F. velutipes was sensitive to bacterial contamination in cultivation. • Two natural biopolymers, ε-poly- l- lysine and chitosan, can effectively inhibit bacteria co-cultured with F. velutipes. • The antibacterial activity was enhanced by combining ε-poly- l - lysine with chitosan. • Hurdle technology was first applied to the control of bacteria in a submerged culture of F. velutipes for liquid spawn production. • The models were established to predict the growth of bacteria in the submerged production of F. velutipes liquid spawn. Flammulina velutipes is a commercially important mushroom that widely cultivated in East Asia. Sawdust spawn is extensively adopted in the cultivation of mushrooms including F. velutipes. Recently, the use of liquid spawn has become increasingly popular in mushroom cultivation in China and many other countries. Owing to the high risk of bacterial contamination in a submerged culture of mushroom mycelium, an attempt was made to examine the feasibility of using the hurdle technology to prevent and control bacteria with Escherichia coli and Bacillus subtilis as indicator strains during the production of F. velutipes liquid spawn. Two food-grade natural biopolymers, i.e. ε-poly-lysine (ε-PL) and chitosan, were selected as antimicrobials. Results showed that the mycelial colonization of F. velutipes was poor or inhibited completely by both indicator strains at the density higher than 10 colony-forming units (CFU)/mL present in the liquid spawn. In submerged cultures, F. velutipes was greatly suppressed by ε-PL at 0.25 mg/mL, and this was 0.30 mg/mL for chitosan. When combined, ε-PL and chitosan did not result in a significant enhancement of activity against the fungus. The antibacterial effects were enhanced when ε-PL and chitosan were combined at an ε-PL/chitosan mass ratio of 3:2. For effectively inhibiting the bacteria co-cultured with F. velutipes , ε-PL, chitosan, and temperature were designed as hurdles. Two mathematical models relating inhibition of E. coli and B. subtilis , respectively, were established by response surface methodology, and could be used to predict the behavior of the culture system. This study provides useful guidelines for the production of a reliable and high-quality liquid spawn of F. velutipes or other mushrooms. [ABSTRACT FROM AUTHOR]

The Taiwan Strait serves as a link between the East China Sea and South China Sea in East Asia. Complex ocean dynamics, huge sediment inputs and distinct tectonic, climatic and bedrock lithological settings of the two sides of the strait make it ideal for sediment source-to-sink studying. While mud sediments in the strait have been well investigated, sand composition and provenance remain understudied. Here, we present framework petrography and heavy mineral data of sands from the southern Taiwan Strait and the adjacent representative rivers to characterize sand provenance and depositional mechanisms. As expected, the SE China river sands are dominated by quartz and feldspar, whereas sands from the westward-flowing mountainous rivers in Taiwan are rich in lithic fragments and heavy minerals of metamorphic origin. The southern Taiwan Strait sands show significant spatial variations in composition and texture of the framework grains and heavy minerals. Framework grain-based provenance modeling results show that sands in the southwest margin of Taiwan Strait (water depth of 30–60 m) are mainly supplied by SE China rivers. Taiwan mountainous rivers made prominent contributions to the central-western Taiwan Strait (40–60 m) and the south of Taiwan Shoal (below 50 m), both of which are far away from the Taiwan island (ca. 100–300 km away). Furthermore, sands from the Taiwan Shoal (20–30 m) show extremely high compositional maturity and are mainly composed of coarse, rounded quartz. These sands, previously proposed as relict sediments, have been intensely altered by modern high-energy hydrodynamic conditions and can also be interpreted as palimpsest sediments. These results demonstrate that modern river-derived sands are eventually deposited in relatively deep-water regions in the strait, rather than the shallow regions (Taiwan Shoal). We propose that the sand composition and distribution are closely related to the submarine topography of the Taiwan Strait. Combining previous mud belt investigations, we suggest that sands and muds tend to have different fates in shallow continental shelves with complex climate, ocean current and seafloor landform conditions. This study also highlights the importance of both modern and relict sands in the strait and our findings are important to better understanding of shelf sedimentary systems with huge river-sediment-input and high wave/tidal-current-energy. • Composition and texture of Taiwan Strait surficial sands vary spatially. • Four deposit areas in southern Taiwan Strait were identified. • Palimpsest sediments of high maturity are preserved in Taiwan Shoal. • Sand distribution in Taiwan Strait is related to submarine topography. [ABSTRACT FROM AUTHOR]

The Zhe-Min mountainous rivers in SE China are characterized by stable tectonics, small–mesoscale drainage basins, relatively homogenous bedrocks, dense vegetation cover and high rainfall conditions. These rivers deliver loads of sediments and nutrients to the oceans and always indicate considerably high variability of sediment flux on short-term timescales. However, short-term sediment compositional variations and transport mechanism by these mountainous rivers remain poorly understood. Here we target the Minjiang River, use mineralogical and trace element geochemical data of suspended particulate matters (SPMs) within a one-year hydrological cycle (from October 2016 to October 2017), riverbed sediments (<0.063 mm fractions) and SPMs from the mainstream and major tributaries, to investigate their provenance and transport process. The results indicate that the SPMs in different seasons have strong seasonal geochemical heterogeneity, with highly positive correlations between several trace element ratios (e.g. La (CN) /Yb (CN) and Th/Sc) and runoff of the river. Riverbed sediments and SPMs collected in pairs have distinct geochemical compositions. The riverbed sediments have relatively low La (CN) /Yb (CN) (ca. 10–15) and Th/Sc (ca. 2–5) ratios, whereas the SPMs have La (CN) /Yb (CN) and Th/Sc ratio ranges of ca. 14–17 and ca. 4–7, respectively. These findings suggest a predominant hydrologic control on the Minjiang River sediment transport and geochemical compositions on a seasonal timescale. We conclude that exposed riverbed sediments are probably selectively recycled in dry-season sediment transport, whereas the flood-season SPMs are less mixed with riverbed sediments and are likely dominated by particulates directly from those tributaries and the upper mainstream. We favor that the Zhe-Min mountainous rivers are featured by rapid sediment delivery in response to hydroclimatic changes and have similar sediment transport behaviors with those small mountainous rivers in tectonically active regions of the subtropical East Asia (e.g. Taiwan). This case study also highlights the importance of multi-spatio-temporal scale, heterogeneous river input of chemical elements to the oceans. • Minjiang River sediments are investigated for mineralogy and geochemistry. • Riverbed sediments and SPMs in pairs have distinct geochemical compositions. • La/Yb and Th/Sc ratios of SPMs correlate positively with the river runoff. • Riverbed and overbank sediments are selectively recycled in dry season transport. • The river shows a hydrologic control on sediment geochemical compositions. [ABSTRACT FROM AUTHOR]