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Typhoons are commonly occurring disastrous events in the Western Pacific and have become more severe as the result of global climate changes, increasingly affecting the ocean and seafloor throughout the Western Pacific. However, studies on the influences of typhoon processes and dynamic mechanisms on the continental shelf remain rather limited because of insufficient observational data in the area. This paper uses observational records at a water depth of 110 m on the continental shelf of the East China Sea in the periods when the No. 1323 typhoon 'Fitow' and No. 1324 typhoon 'Danas' passed the East China Sea to study changes in the water temperature, salinity, current and turbidity. Observation results show that typhoon Fitow had limited effects on the measurement site because of the long distance to the centre of the typhoon, but during typhoon Danas, the measured surface current speed reached 2.95 m/s, and the turbidity of the sea water increased rapidly due to the vertical mixing of sea water. Typhoon Danas causes both near-inertial oscillations (NIOs) and diurnal currents to increase, which is considered to be the major factor that contributes to bottom water temperature changes and the suspension of bottom sediments after the passage of the typhoon. Typhoons can also cause the Kuroshio Current to shift towards the continental shelf, which may affect the Tsushima Current. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Previous studies carried out in the East China Sea (ECS) mud area focused on long-term environmental changes in sedimentary records during the Holocene, especially during the mid-Holocene high-stand water levels period. These results indicate that sensitive grain size groups can be used as a sedimentary proxy to reconstruct the evolution of the East Asian Winter Monsoon (EAWM). The studies have been carried out mainly in the northern and middle portions of the Zhejiang-Fujian coastal mud, however, similar research in the southern portion and the comparison between sedimentary proxy and modern measured data of EAWM are lacking. In this paper, we focused on a sedimentary record of the past 100 years with an enhanced resolution of 1.8 years. Investigations of the southern end of the Zhejiang-Fujian coastal mud area were conducted on the basis of Pb chronology, grain-size analysis and chemical element analysis. The correspondence between the mean grain size (Mz) of sediment sensitive grain size and the measured EAWM was confi rmed for the fi rst time. We found that during the recent 100 years, the variation of the mean grain size of the sensitive population in the southern portion of the Zhejiang-Fujian mud was mainly controlled by the EAWM intensity changes; and not directly related to changes in the sediment discharge from Datong station of the Changjiang River (DTSD). Finally, recent changes in the content of heavy metals in study area refl ect the impact of human activities on the environment. [ABSTRACT FROM AUTHOR]

Precipitation data from 30 stations in the Huaihe River basin (HRB), a climatic transitional zone in east China, were used to investigate the spatiotemporal variability and trends of extreme precipitation on multitimescales for the period 1961–2010. Results indicated that (1) the spatial pattern of the annual precipitation, rainy days, extreme precipitation, and maximum daily precipitations shows a clear transitional change from the south (high) to the north (low) in the HR; it confirmed the conclusion that the HRB is located in the transitional zone of the 800 mm precipitation contour in China, where the 800 mm precipitation contour is considered as the geographical boundary of the south and the north. (2) Higher value of the extreme precipitation intensity mainly occurs in the middle of the east and the central part of the basin; it reveals a relatively distinct west-east spatial disparity, and this is not in line with the spatial pattern of the extreme precipitation total, the sum of the precipitation in 95th precipitation days. (3) Annual precipitation of 22 stations exhibits increasing trend, and these 22 stations are located from the central to the northern part. There is no significant trend detected for the seasonal precipitation. The summer precipitation exhibits a larger change range; this might cause the variation of the flood and drought in the HBR. However, the increasing trend in winter precipitation may be beneficial to the relief of winter agricultural drought. Rainy days in 12 stations, mostly located in and around the central northeastern part, experienced significant decreasing trend. Extreme precipitation days and precipitation intensity have increasing trends, but no station with significant change trend is detected for the maximum precipitation of the basin. (4) The spatiotemporal variability in the HRB is mainly caused by the geographic differences and is largely influenced by the interdecadal variations of East Asian Summer Monsoon in eastern China. The output of this paper could provide references for the practical decision making and integrated basin management of Huaihe River basin. [ABSTRACT FROM AUTHOR]

Secondary inorganic ions are important constituents of PM2.5 that play an important role in global climate change through direct and indirect radiative forcing. To investigate the influence of ship emissions on coastal cities, we launched a cruise ship campaign offshore of the East China Sea (ECS) and two field observation sites in the megacity of Shanghai using 1‐hr time‐resolved water‐soluble ion chromatography from June 3 to June 27, 2017. Three main secondary inorganic soluble ions in the atmosphere of the ECS, that is, non‐sea‐salt sulfate (nss‐SO42−), NO3− and NH4+, were 8.87, 4.94, and 4.65 μg m−3, respectively. While their values at the Pudong (PD) station in urban Shanghai were 6.33, 9.47, and 4.74 μg m−3 and at the Dianshanhu (DSH) station in suburban Shanghai were 7.33, 10.01, and 6.78 μg m−3, respectively. Nss‐SO42− was dominant in the PM2.5 in the atmosphere of the ECS (nss‐SO42−/NO3− = 1.8), and mainly distributed near the Zhoushan Islands of the ECS. This indicated significant contributions from ship emissions. Based on the Community Multiscale Air Quality model, two main sources of nss‐SO42− were identified: emissions and horizontal transport. These comprised over 90% of the nss‐SO42−. The influence of ship emissions reached up to 31.6% of the total nss‐SO42− alongside the cruise ship and near coastal parking ports in the Yangtze River Delta area, suggesting that more attention should be paid to ship emissions. Key Points: Non‐sea‐salt sulfate (Nss‐SO42−) was dominant in PM2.5 on East China Sea, which was distributed around Zhoushan Islands indicating a significant contributor of ship emissionTwo main source processing of nss‐SO42− were categorized using Community Multiscale Air Quality: emission and horizontal transportInfluence of ship emission reached up to 31.6% of total nss‐SO42− alongside ship cruise and near coastal parking ports in Yangtze River Delta area [ABSTRACT FROM AUTHOR]

Watson, P.J., 2019. Updated mean sea-level analysis: South Korea. Journal of Coastal Research, 35(2), 241–250. Coconut Creek (Florida), ISSN 0749-0208. The threat of sea-level rise to the heavily populated Korean Peninsula has profound and far-reaching implications. This study updates and extends the several previous works undertaken to analyse tide-gauge records and satellite altimetry around South Korea using enhanced time-series analysis techniques to detect coastal vertical land motion and current rates of rise and accelerations in mean sea level to augment planning, design, and risk management activities. Although the longest tide-gauge records available only date back to 1960, every effort has been made to separate the mean sea-level trend from the more dynamic influences with improved precision using state-of-the-art analytical techniques. The analysis identified general trends of subsidence observed around the margins bounded by the East China Sea and East Sea (Sea of Japan) below 36°N, whereas uplift was a more prevalent feature along the margins bounded by the Yellow Sea. All tide-gauge records longer than 50 years exhibited 'relative' mean sea-level rise increasing marginally over the length of the record, suggesting the presence of an acceleration; however, the estimated time-varying accelerations (albeit predominantly positive) are small and not statistically different from zero (95% confidence interval). Although the average trend of sea-surface height from satellite altimetry across this region was 3.2 mm/y, key spatial variations were evident, with the highest rates of rise centred in two discrete areas east and west of South Korea around 37.5°N, each exceeding 8 mm/y. [ABSTRACT FROM AUTHOR]

Corals and their associated fauna are extremely diverse in tropical waters and form major reefs. In the high-latitude temperate zone, corals living near their distribution limit are considered marginal communities because they are particularly extremely sensitive to environmental and climatic changes. In this study, we examined the diversity and host usage of coral-associated barnacles on Jeju Island, Korea, the northern coral distribution limit in the East China Sea. In this study, only three coral-associated barnacles—from two genera in two subfamilies—were collected. The Pyrgomatinid barnacles Cantellius arcuatus and Cantellius cf. euspinulosum were found only on the corals Montipora millepora and Alveopora japonica, respectively. The Megatrematinid barnacle Pyrgomina oulastreae, relatively a generalist, was found on Psammocora spp. (both profundacella and albopicta) and Oulastrea crispata corals. The host usage of these three barnacles does not overlap. DNA barcode sequences of the C. arcuatus specimens collected in the present study matched those collected in Kochi in Japan, Taiwan, Malaysia and Papua New Guinea, suggesting that this species has a wide geographical distribution. C. arcuatus covers a wider host range in Taiwan waters, inhabiting Montipora spp. and Porites spp., which suggests that the host specificity of coral-associated barnacles varies with host availability. C. cf. euspinulosum probably has a very narrow distribution and host usage. The sequences of C. cf. euspinulosum on Jeju Island do not match those of any known sequences of Cantellius barnacles in the Indo-Pacific region. P. oulastreae probably prefers cold water because it has been reported in temperate regions. Coral-associated barnacles in marginal communities have considerably lower diversity than their subtropical and tropical counterparts. When host availability is limited, marginal coral-associated barnacles exhibit higher host specificity than those in subtropical and tropical reef systems. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that the low-frequency sea surface temperature (SST) variability in the Yellow Sea and East China Sea (YECS) is linked to large-scale climate variability, but explanations on the mechanisms vary. This study examines the low-frequency variability and trends of some atmospheric and oceanic variables to discuss their different effects on the YECS warming. The increasing temperature trend is also observed at a hydrographic section transecting the Kuroshio. The increasing rate of ocean temperature decreases with depth, which might result in an increase in vertical stratification and a decrease in vertical mixing, and thus plays a positive role on the YECS warming. The surface net heat flux (downward positive) displays a decreasing trend, which is possibly a result of the YECS warming, and, in turn, inhibits it. Wind speeds show different trends in different datasets, such that its role in the YECS warming is uncertain. The trends in wind stress divergence and curl have large uncertainties, so their effects on SST warming are still unclear. The Kuroshio heat transport calculated in this study, displays no significantly increasing trend, so is an unlikely explanation for the SST warming. Limited by sparse ocean observations, sophisticated assimilative climate models are still needed to unravel the mechanisms behind the YECS warming. [ABSTRACT FROM AUTHOR]

This study was designed to determine the effects of flooding on a pelagic ecosystem in the East China Sea (ECS) with a focus on plankton activity and plankton community respiration (CR). In July 2010, a flood occurred in the Changjiang River. As a comparison, a variety of abiotic and biotic parameters were monitored during this flooding event and during a non-flooding period (July 2009). During the flood, the Changjiang diluted water (CDW) zone covered almost two-thirds of the ECS, which was approximately 6 times the area covered during the non-flooding period. The mean nitrate concentration was 3-fold higher during the 2010 flood (6.2 vs. 2.0μM in 2009). CR was also higher in the 2010 flood: 105.6 mg Cm-3 d-1 vs. only 73.2 mg Cm-3 d-1 in 2009. The higher CR in 2010 could be attributed to phytoplankton respiration, especially at stations in the CDW zone that were not previously characterized by low sea surface salinity in 2009. In addition, zooplankton (> 330 μm) were another important component contributing to the high CR rate observed during the 2010 flood; this was a period also associated with a significant degree of fCO2 drawdown. These results collectively suggest that the 2010 flood had a significant effect on the carbon balance in the ECS. This effect might become more pronounced in the future, as extreme rainfall and flooding events are predicted to increase in both frequency and magnitude due to climate change. [ABSTRACT FROM AUTHOR]

The seasonal mean and synoptic fluctuation of the wintertime Taiwan Warm Current (TWC) were investigated using a well-validated finite volume community ocean model. The spatial distribution and dynamics of the synoptic fluctuation were highlighted. The seasonal mean of the wintertime TWC has two branches: an inshore branch between the 30 and 100m isobaths and an offshore branch between the 100 and 200m isobaths. The Coriolis term is much larger than the inertia term and is almost balanced by the pressure gradient term in both branches, indicating geostrophic balance of the mean current. Two areas with significant fluctuations of the TWC were identified during wintertime. One of the areas is located to the north of Taiwan with velocities varying in the cross-shore direction. These significant crossshore fluctuations are driven by barotropic pressure gradients associated with the intrusion of the Taiwan Strait Current (TSC). When a strong TSC intrudes to the north of Taiwan, the isobaric slope tilts downward from south to north, leading to a cross-shore current from the coastal area to the offshore area. When the TSC intrusion is weak, the crossshore current to the north of Taiwan is directed from offshore to inshore. The other area of significant fluctuation is located in the inshore area between the 30 and 100m isobaths. The fluctuations are generally strong both in the alongshore and cross-shore directions, in particular at the latitudes 26.5 and 28° N. Wind affects the synoptic fluctuation through episodic events. When the northeasterly monsoon prevails, the southwestward Zhe-Min coastal current dominates the inshore area associated with a deepening of the mixed layer. When the winter monsoon is weakened or the southwesterly wind prevails, the northeastward TWC dominates in the inshore area. [ABSTRACT FROM AUTHOR]

A gravity core collected from the East China Sea (ECS) inner shelf was analyzed for elemental and stable isotopic composition, lignin-phenols, and sedimentary pigments to investigate changes of organic carbon (OC) inputs during the past two centuries. In particular, we examined the linkages between terrestrial and marine OC inputs with climate variability and anthropogenic activities. The decrease of terrestrial OC contribution (from 41% to 28%) and increasing diagenetic indices of lignin-phenols (P/(S + V): from 0.12 to 0.22; 3,5-Bd/V: from 0.03 to 0.09) after the 1970s were possibly attributed to intensified deforestation, dam construction, and channel erosion. Lignin content (Λ8) ranged from 0.35 mg/100 mg OC to 6.92 mg/100 mg OC, with lower values corresponding to the worst flooding events in the Changjiang watershed and weaker East Asian Winter Monsoon (EAWM), while higher Λ8 was more correlated to the strengthening of EAWM. This indicates that terrestrial inputs to Zhe-Min Coast are different from those in Changjiang Estuary during flooding events and strongly linked with regional climate variability. The total contents of sedimentary chloropigments (i.e. pheophorbide-a, pheophytin-a, pyropheophytin-a, sterol chlorin esters, and carotenol chlorin esters) ranged from 663.4 to 74.9 nmol g−1 OC, and decreased exponentially downwards. Sedimentary chloropigments that were used to document historical change of phytoplankton biomass were decoupled with historical changes of Changjiang riverine nutrient inputs but corresponded well to the fluctuation of regional climate variability. Higher phytoplankton biomasses usually were observed during positive phases of Pacific Decadal Oscillation (PDO) and/or warm El Niño-Southern Oscillation (ENSO) events, and lower algal biomass usually corresponded to the negative phase of PDO and/or cold ENSO events. [ABSTRACT FROM AUTHOR]

Sediment settling velocity ( w) patterns are well established at the Huanghe and Changjiang river mouths, but no w results have been reported for the Yellow Sea and the East China Sea (YSECS) shelves due to the labor-intensive and time-consuming aspect of traditional w measurement approaches (e.g., settling column method). This disadvantage can be overcome by the acoustic Doppler velocimeter (ADV). In this study, ten ADV-based field campaigns were conducted over various seasons of the years 2011 and 2013 at six YSECS sites, five on the East China Sea shelf (28 to 87 m depth) and one on the Yellow Sea shelf (74 m depth). The results demonstrate that ADV backscatter was a reliable proxy of suspended sediment concentration over a measurement range of 1 to 1,000 mg/L. The ADV-estimated w was highest (1.43-1.88 mm/s) in summer in the southern East China Sea, and lowest (0.07 mm/s) in spring in the northern Yellow Sea. This can plausibly be explained by the hydrodynamic environment and bottom sediment type at the campaign sites. More importantly, the data reveal evidence of marked seasonal variations of w in the middle sector of the East China Sea, as well as intra-tidal variations at all campaign sites. However, these variations of w are not directly regulated by current velocity or suspended sediment concentration. This aspect represents a major challenge in future research in this shelf region and, for that matter, in similar settings worldwide. Evidently, expanding on the well-resolved continuous time series provided by the ADV approach is a key step in this direction. [ABSTRACT FROM AUTHOR]

The self-organizing map method is applied to satellite-derived sea-level anomaly fields of 1993-2012 to study variations of the Kuroshio intrusion northeast of Taiwan Island. Four major features are revealed, showing significant seasonal variability of the intrusion. In general, the intrusion increases (decreases) with a high (low) sea-level anomaly at the edge of the East China Sea shelf in winter (summer). Open-ocean mesoscale eddies play an additional role in modulating the seasonal variation of the intrusion. Further analyses are needed to study eddy-Kuroshio interaction dynamics. [ABSTRACT FROM AUTHOR]

Holocene changes in fine-grained sediment supplies to the East China Sea outer shelf were uncovered, through the mineralogical and geochemical analysis of Core B3 in the East China Sea Distal Mud (ECSDM). Based on the lithology, accelerator mass spectrometry (AMS) 14C dating, and sea-level change, Core B3 can be divided into two major units: transgressive stage (Unit 1: 12.5–6.8 kyr) and highstand stage (Unit 2: 6.8–0 kyr). Significant discrepancy of dolomite/calcite ratio in the fine fractions (<16 µm) of Changjiang (dolomite/calcite = 3:1) and Huanghe (dolomite/calcite = 1:22) sediments was used as a new uniqueness provenance tracer to distinguish these two riverine sources. Both of the dolomite/calcite ratio and rare earth elements fractionation parameters in the fine-grained sediment indicated distinct provenance shifts of Core B3 during the Holocene. Unit 1 of Core 3 (12.5–6.8 kyr) mainly consists of the reworked and resuspension sediments of the East China Sea shelf during the Holocene transgression, while Unit 2 sediments (6.8–0 kyr) are most likely sourced from the Changjiang and Huanghe. Moreover, mixing curves of dolomite/calcite ratio reveal that the ECSDM continuously received the Changjiang sediment since 6.1 kyr with notable fluctuations, whereas the Huanghe sediment supply began in 6.8 kyr but abruptly stopped during 4.2–0.8 kyr and then appeared again since 0.8 kyr. Temporal changes of the Changjiang and Huanghe fine-grained sediment contribution to the ECSDM are closely related to the formation of modern oceanic circulation system since 6.8 kyr (shelf sea-level change), the ‘4.2 kyr’ climate event, and the followed transition to cold and dry climate condition in the northeastern China (global climate change), as well as the artificial shift of lower Huanghe course in ad 1128 in the war against invasion of the northern nomadic nation (human activities). [ABSTRACT FROM AUTHOR]

Seasonal variations of water masses in the East China Sea (ECS) and adjacent areas are investigated, based on historical data of temperature and salinity ( T-S). Dynamic and thermodynamic mechanisms that affect seasonal variations of some dominant water masses are discussed, with reference to meteorological data. In the ECS above depth 600 m, there are eight water masses in summer but only five in winter. Among these, Kuroshio Surface Water (KSW), Kuroshio Intermediate Water (KIW), ECS Surface Water (ECSSW), Continental Coastal Water (CCW), and Yellow Sea Surface Water (YSSW) exist throughout the year. Kuroshio Subsurface Water (KSSW), ECS Deep Water (ECSDW), and Yellow Sea Bottom Water (YSBW) are all seasonal water masses, occurring from May through October. The CCW, ECSSW and KSW all have significant seasonal variations, both in their horizontal and vertical extents and their T-S properties. Wind stress, the Kuroshio and its branch currents, and coastal currents are dynamic factors for seasonal variation in spatial extent of the CCW, KSW, and ECSSW, whereas sea surface heat and freshwater fluxes are thermodynamic factors for seasonal variations of T-S properties and thickness of these water masses. In addition, the CCW is affected by river runoff and ECSSW by the CCW and KSW. [ABSTRACT FROM AUTHOR]

The temporal and spatial variability of the Kuroshio Current was analyzed. Current data were estimated from hydrographic data collected from areas within the central East China Sea (PN section) from 1955 to 2010 and the Tokara Strait (TK section) from 1987 to 2010. To reduce the bias caused by cruise-dependent spatial resolution among the data, grid-consistent temperature and salinity fields were reconstructed by use of a regression relationship to account for anomalies between observed stations and grid points. The mass imbalance problem between the PN and TK sections, which appears stochastically when viewed by use of the dynamic method, was solved by use of the inverse method. The estimated Kuroshio volume transport (KVT) was found to be closely consistent with that of current observations and had an uncertainty of 2.4 Sv. The KVT seemed to have neither a regime shift in approximately 1976 nor a sharply increasing trend. The KVT was dominated by 2-5 year modulating interannual variability with an amplitude of 2.8 Sv, followed by weak 20-year decadal variability with an amplitude of 0.33 Sv. Empirical orthogonal function analysis of the currents suggested that the temporal and spatial variability of the Kuroshio Current in the PN section was dominated by a transport mode, manifested by the high variability of current on the seaward side of current core with expansion or shrinkage of the core. In contrast, the temporal and spatial variability of the Kuroshio Current in the TK section was dominated by a meandering mode, as indicated by the migration of the Kuroshio axis in the south gap of the Tokara Strait. [ABSTRACT FROM AUTHOR]

This study analyses the extreme high flows in Jinhua River basin under the impact of climate change for the near future 2011-2040. The objective of this study is to investigate the effect of using the bias corrected RCM outputs as input on the extreme flows by hydrological models. The future projections are obtained through the PRECIS model with resolution of 50 km × 50 km under climate scenario A1B. The daily precipitation from the PRECIS is bias corrected by distribution based scaling method. Afterwards, three hydrological models (GR4J, HBV and Xinanjiang) are calibrated and applied to simulate the daily discharge in the future. The hydrological models are driven with both bias corrected precipitation and raw precipitation from the PRECIS model for 2011-2040. It is found that after bias correction, the amount, frequency, intensity and variance of the precipitation from the regional climate model resemble the observation better. For the three hydrological models, the simulated annual maximum discharges are higher by using the raw precipitation from PRECIS than by bias corrected precipitation at any return period. Meanwhile, the uncertainties from different models cannot be neglected. The largest difference between three models is about 2,100 m/s. [ABSTRACT FROM AUTHOR]

High inter-annual and inter-decadal variability was identified in the Kuroshio heat transport (KHT), primarily following 5.4-, 22- and 2-year cycles. The KHT experienced a sharp climatic jump around 1976. Inter-decadal variability of the KHT was strongly associated with the Pacific Decadal Oscillation (PDO). A linear long-term KHT upward trend was identified from 1956 to 2003, and the KHT increased 0.65 × 1015 W in this period. The northeastward volume transport of the Kuroshio made a greater contribution to the KHT across the PN section than sea temperature did. Correlation and composite analyses showed that the meridional wind anomalies over the Kuroshio area and the southern portion of the South China Sea were responsible for the inter-annual variability of the KHT in the East China Sea, i.e. the KHT increased (decreased) when the southerly (northerly) anomalies strengthened. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

AMS14C dating and analysis of grain size, major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea. Based on the environmentally sensitive grain size, clay mineral and major element assemblages, the history of the East Asia winter monsoon since the mid-Holocene could be reconstructed. These three proxies, mean grain size (>9.71 µm), chemical index of alteration (CIA) and ratio of smectite to kaolinite in particular, show similar fluctuation patterns. Furthermore, 10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene; these extreme values are likely to have been caused by the strengthening of the East Asia winter monsoon. The cooling events correlated well with the results of the δ 18 O curves of the Dunde ice core and GISP2, which therefore revealed a regional response to global climate change. Four stages of the East Asia winter monsoon were identified, i.e. 8300-6300 a BP, strong and unstable; 6300-3800 a BP, strong but stable; 3800-1400 a BP, weak and unstable; after 1400 a BP, weak but stable. [ABSTRACT FROM AUTHOR]

A pollen record of core PC-1 from the northern Okinawa Trough, East China Sea (ECS), provides information on vegetation and climate changes since 24 cal. kaBP. A total of 103 samples were palynologically analyzed at 8 cm intervals with a time resolution of 230 a. Four pollen zones are recognized: zone I (812-715 cm, 24.2-21.1 cal. kaBP), zone II (715-451 cm, 21.1-15.2 cal. kaBP), zone III (451-251 cm, 15.2-10.8 cal. kaBP), zone IV (251-0 cm, 10.8-0.3 cal. kaBP), corresponding to Late MIS 3, Last Glacial Maximum (LGM), deglaciation and Holocene, respectively. The LGM is characterized by the dominance of herbs, mainly Artemisia, and high pollen influx, implying an open vegetation on the exposed continental shelf and a cool and dry climate. The deglaciation is a climate warming stage with Pinus percentage increased and Artemisia percentage decreased and a rapid sea-level rise. The Holocene is characterized by predominance of tree pollen with rapid increase in Castanea-Castanopsis indicating the development of mixed evergreen and deciduous broad-leaved forest and a warm, humid climate. Low pollen influx during the Holocene probably implies submergence of the continental shelf and retreat of the pollen source area. The vegetation indicated by pollen assemblage found in this upper zone is consistent with the present vegetation found in Kyushu, Japan. Originating from the humid mountain area of North Luzon of the Philippines, Tasmania and New Zealand, Phyllocladus with sporadic occurrence throughout PC-1 core probably suggests the influence of Palaeo-Kuroshio Current or intense summer monsoon. The observed changes in Pinus and Herbs percentage indicate fluctuations of the sea level, and high Pinus percentage corresponds to high sea level. Spectrum analysis of the pollen percentage record reveals many millennial-scale periodicities, such as periodicities of 6.8, 3.8, 2.2, 1.6 ka. [ABSTRACT FROM AUTHOR]

• Kirengeshoma comprises two species inhabiting warm temperate-deciduous forests in East China/South Japan ( Kirengeshoma palmata) and South Korea ( Kirengeshoma koreana). A survey of chloroplast (cp) DNA and inter-simple sequence repeats (ISSRs) variation in Kirengeshoma was carried out to determine the population history of a plant taxon around the East China Sea (ECS). • CpDNA and ISSRs revealed lower genetic divergence between China and Japan relative to the other contrasts, in line with intrageneric classification. Molecular dating suggests that K. koreana diverged at the Plio-Pleistocene boundary from the Japanese populations, whereas the latter migrated into China during the early-to-mid Pleistocene via the ECS basin. Vicariant segregation of Chinese and Japanese populations likely occurred during the mid-Pleistocene. • Mismatch distributions and neutrality tests indicated that Chinese populations expanded their range during the Late Pleistocene, probably during a cold period, whereas those from Japan showed no significant population growth. • We conclude that the current distribution and differentiation of components of presently isolated warm temperate-deciduous forests in China, Japan and Korea likely resulted from a combination of relatively ancient vicariant and immigration events, and those from Japan were particularly sensitive to range fragmentation and long-term refugial isolation throughout the Late Pleistocene. [ABSTRACT FROM AUTHOR]