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Extreme precipitation events (EPEs) and heatwaves (HWs) can trigger floods, droughts, and other natural disasters, resulting in severe socioeconomic losses in eastern China. However, the accurate links between EPEs and HWs and future changes in these extremes are not fully resolved, which potentially impedes disaster warning and preparedness efforts. This study examines historical and future changes in summer EPEs and HWs in eastern China based on observations and model outputs from the Coupled Model Intercomparison Project Phase 6. The results show that EPEs and HWs in eastern China have increased in the past four decades and are projected to rise in the future. According to multi-model projections, the Yangtze River Basin, along with areas to its south, are expected to experience an increase in compound disasters due to HWs and EPEs. High values of the multi-year mean total population exposure to EPEs and HWs are observed in the North China Plain, Yangtze River Delta, Sichuan Basin, and southeast coast. The total population exposure to EPEs shows a decreasing trend under Shared Socioeconomic Pathway (SSP) 245 and SSP585 scenarios during 2021–2100, consistent with future population decline. However, the annual total population exposure to HWs will increase, reaching nearly 3.0 billion and 5.0 billion by the end of the century under the SSP245 and SSP585 scenarios, respectively. Within the context of global warming, the relationship between the mean-state of precipitation and maximum temperature as well as the relationship between extreme precipitation and heatwaves shift from negative correlation in the historical period to positive correlation in future projections for eastern China. [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHWs) are prevalent in the South China Sea (SCS) and are primarily caused by the anomalous western Pacific subtropical high (WPSH) which suppresses the SCS summer monsoon. Our study investigates future summer MHWs in the SCS in response to the enhanced WPSH. The results show that the WPSH will be strengthened in most models under the highest emission scenario. Total days of summer SCS MHWs will significantly increase with the enhancement of the WPSH and peak at the end of the 21st century. The high‐value area of total days of summer MHWs (>50 days) appears in the south‐central SCS. The intensity of MHWs exhibits little response to the strengthening WPSH. In addition, the weakening of the SCS cold filament due to the anomalous WPSH also favors summer MHWs. Furthermore, increased future severe summer SCS MHWs will create a higher bleaching risk for coral reefs. Plain Language Summary: Marine heatwaves (MHWs) can have devastating impacts on marine ecosystems when seawater temperatures are warmer than the 90th percentile for at least five consecutive days based on a fixed 30‐year (or longer) baseline. The western Pacific subtropical high (WPSH) is an anticyclonic system in the northwestern Pacific that affects MHWs in the South China Sea (SCS). Based on the latest climate models, we calculate the total days and intensity of summer MHWs in the SCS under increased variability in the WPSH in future projections. Total days of summer MHWs will rapidly increase and peak at the end of the 21st century. Furthermore, the total days of summer MHWs are associated with SCS upwelling and cold filament, which is also influenced by strong WPSH. More concerning are the increases in severe summer MHWs, which will make coral reefs more susceptible to bleaching in the SCS in the future. Key Points: Increasing variability in the western Pacific subtropical high (WPSH) leads to more frequent, stronger WPSH events in future projectionsThe total days and intensity of summer marine heatwaves (MHWs) in the South China Sea (SCS) show different responses to the enhanced WPSHTotal days of summer MHWs in the SCS increase with the strengthened WPSH, resulting in a high coral bleaching risk [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHWs) are persistent, discrete, extreme high-temperature events in the ocean, which can destructively affect marine ecosystems. Using satellite remote sensing data and reanalysis data from 1982 to 2021, we find that six indices characterizing the MHWs are in a remarkable increasing trend in the Japan/East Sea (JES), which shows that the most severe MHW events take place in the East Korean Bay (EKB) in the summer of 2021. Based on this finding, the present study focuses on the characteristics and mechanisms of the MHWs in the EKB and its adjacent areas from June to August 2021. The analysis reveals that the total days and mean intensity of MHWs that occur in the EKB are 1.84 and 1.47 times more than those averaged in the JES, respectively. It is shown that mechanisms for the occurrences of the MHWs in the summer of 2021 are caused by the atmospheric high-pressure system moving to the EKB area. Other reasons also decrease the water cooling: the net positive lateral heat fluxes across open boundaries, and the weak sea surface wind over the EKB area. Other possible reasons which cause the summer MHW events in 2021 need the oceanic numerical models to further investigate the issue. [ABSTRACT FROM AUTHOR]

China experienced significant flooding in the summer of 2020 and multiple extreme cold surges during the winter of 2020/21. Additionally, the 2020 typhoon season had below average activity with especially quiet activity during the first half of the season in the western North Pacific (WNP). Sea surface temperature changes in the Pacific, Indian, and Atlantic Oceans all contributed to the heavy rainfall in China, but the Atlantic and Indian Oceans seem to have played dominant roles. Enhancement and movement of the Siberian High caused a wavier pattern in the jet stream that allowed cold polar air to reach southward, inducing cold surges in China. Large vertical wind shear and low humidity in the WNP were responsible for fewer typhoons in the first half of the typhoon season. Although it is known that global warming can increase the frequency of extreme weather and climate events, its influences on individual events still need to be quantified. Additionally, the extreme cold surge during 16–18 February 2021 in the United States shares similar mechanisms with the winter 2020/21 extreme cold surges in China. [ABSTRACT FROM AUTHOR]

The precipitation concentration index (PCI) is a powerful indicator for temporal precipitation distribution and is also very useful for the assessment of seasonal precipitation changes. The primary objectives of this study are to investigate and analyse the temporal–spatial variability patterns of annual and seasonal PCI values based on monthly precipitation data. These data were collected from 597 meteorological stations located throughout China, for the time period of 1960–2016, and were used to assess the impacts of geographical parameters (latitude, longitude, and altitude) on the PCI. Additionally, the possible teleconnection with the large‐scale circulation pattern was investigated. Our results reveal that the variation trend of annual PCI values has decreased significantly at a rate of −.234/10 year (α = .01) in China over the past 57 years. For all studied station records, 434 (72.7%) stations showed decreasing trends of PCI values, and these stations are distributed over large areas in China. On an annual scale, the average PCI value ranged from 11 in Hunan province to 44 in Qinghai province. The precipitation concentration in China can be described as strongly irregular in the western and northern parts of the northwest and in the northern region of the Tibetan Plateau, while it is irregular in the southwest and the north of China, and moderately irregular in some parts of the middle‐lower regions of the Yangtze River and southern China. The regularity of the annual precipitation pattern significantly decreased in spring, autumn, and winter from southeastern to northwestern China, and was the most in winter. However, the summer precipitation dispersion and the pattern in the considered period were more regular than those of the other seasons. Furthermore, changes in the PCI appear to be rather complex and possibly related to global atmospheric characteristics as well as geographical factors (latitude, longitude, and altitude). The results presented in this study indicate that the PCI is an essential feature for water resource planning, prediction of risk due to droughts or floods, and the management of natural resources. [ABSTRACT FROM AUTHOR]

This study investigated the spatial-temporal patterns and trends of potential evapotranspiration (ET0) and aridity index (AI) over Southwest China during 1960-2013 based on daily temperature, precipitation, wind speed, sunshine duration, total solar radiation, and relative humidity data from 108 meteorological stations. The Penman-Monteith model, Mann-Kendall (M-K) test, moving t test, and Morlet wavelet method were used. The results indicated that ET0 and AI across the region displayed decreasing trends, but the former was significant. After 2000, regionally average trends in ET0 and AI increased rapidly, indicating that droughts increased over Southwest China in recent years. Spatially, the changes of ET0 and AI were dissimilar and not clustered, either. Temporally, both ET0 and AI displayed obvious abrupt change points over different timescales and that of AI was during the winter monsoon period. Significant periodic variations with periods of 27, 13, and 5 years were found in ET0, but only of 13 and 5 years existed in AI. Correlation analysis revealed that the sunshine duration and wind speed were the dominant factors affecting ET0 and that AI showed strong negative correlation with precipitation. The findings of this study enhance the understanding of the relationship between climate change and drought in Southwest China, while the mechanism controlling the variation in drought requires further study. [ABSTRACT FROM AUTHOR]

Record-breaking marine heatwaves (MHWs) occurred in the western North Pacific during the summer of 2020. These unprecedented MHWs were consistent with favorable large-scale conditions that are linked to an anomalous western North Pacific subtropical high (WNPSH), resulting mainly from sea surface temperature (SST) anomalies across the tropical oceans. In addition, a moderate La Niña-like pattern was also conducive to transporting warm seawater to the western North Pacific. Mixed-layer heat budgets suggest that surface heat flux contributed to the SST anomaly in the western subtropical Pacific. In contrast, oceanic heat advection dominanted in the South China Sea and the western equatorial Pacific. Numerical model experiments indicated that the tropical Indian Ocean SST anomalies were responsible for the enhanced WNPSH. The increased zonal SST gradient across the tropical Pacific also played an important role. Inter-ocean interactions can modulate climate variability through ocean-atmospheric coupling and deserve more attention when predicting MHWs within the context of global warming. In addition, it is critical to consider MHWs as a powerful tool in detecting acute, intense thermal stress events in the coral bleaching pre-warning system. [ABSTRACT FROM AUTHOR]

• Total days and average duration of marine heatwaves increased in coral reef zones. • The area ration between marine heatwaves and cold-spells is rapidly increasing. • Upper-ocean warming drives the differences between marine heatwaves and cold-spells. Persistent ocean temperature extremes, known as marine heatwaves (MHWs) and marine cold-spells (MCSs), can be devastating for warm-water coral reefs. However, the difference between MHWs and MCSs in the mean and trend across global coral reef zones in the present and future climates remains unclear. In this study, we comparatively assessed these changes using satellite sea surface temperatures during 1982–2021 and the Coupled Model Intercomparison Project Phase 6 climate model projections during 2022–2070. We found distinct differences in the mean and trend between MHW and MCS metrics across global coral reef zones, with a rapid increase in the total days and average duration of MHWs, whereas the MCSs exhibited an opposite trend. Moreover, the increasing trend in the average duration of MHWs and decreasing trend in MCS frequency both induced a nearly permanent MHW state in future projections. Upper-ocean warming was the main driver of the increase in MHWs and the decrease in MCSs. Under greenhouse warming, the area ratio between the MHW and MCS would rapidly increase from 1982 to 2070, reaching nearly 28 times under the Shared Socio-economic Pathway (SSP) 245 and 109 times under SSP585 by the year 2070. As El Niño-Southern Oscillation (ENSO) events are critical for the occurrence of MHWs and coral bleaching in tropical oceans, our results emphasize the necessity for understanding the projected changes in extreme ENSO events. [ABSTRACT FROM AUTHOR]

Hydrogen is one of the exhaust gases produced by nuclear power stations. Due to the potential danger of incomplete combustion and the emission of hydrogen, hydrogen catalytic combustion is introduced to ensure the safety of nuclear power stations. Palladium is a widely used catalyst for hydrogen catalytic combustion. H2 catalytic combustion on a Pd(111) slab model and Pd38 cluster model were simulated using density functional theory (DFT), in order to analyze the H2 oxidation mechanism on the catalyst surface. [ABSTRACT FROM AUTHOR]

• MiR-215-5p promotion has an inhibitory impact on the inflammation injury. • MiR-215-5p targets ILF3 and LRRFIP1 in LPS-treated H9c2 cells. • Increased miR-215-5p represses the inflammation injury via ILF3 and LRRFIP1. MicroRNAs (miRNAs) are small non-coding RNAs (ncRNAs) playing crucial roles in sepsis-induced diseases, including myocardial inflammation. Nevertheless, the expression pattern and role of miR-215-5p in myocardial inflammation are still un-investigated up to now. The purpose of our study is to further inquire the effect of miR-215-5p on lipopolysaccharide (LPS)-activated inflammation injury in H9c2 cells and the possibly associated mechanisms. First of all, LPS-induced H9c2 cells models were constructed and affirmed via detection of pro-inflammatory factors, the viability and apoptosis. MiR-215-5p was overtly down-regulated in LPS-treated H9c2 cells and miR-215-5p overexpression could suppress the inflammation injury. LRRFIP1 was proved to be the target gene of miR-215-5p and meanwhile, miR-215-5p also targeted ILF3 that experimented to bind to and stabilize LRRFIP1. Final rescue assays confirmed that the overexpression of LRRFIP1 or ILF3 rescued the repressive effect of miR-215-5p up-regulation on the inflammation injury in septic H9c2. Totally, miR-215-5p exerted protective function in the inflammation injury in septic H9c2 via targeting ILF3 and LRRFIP1, suggesting an additional treatment method for sepsis-activated myocardial inflammation. [ABSTRACT FROM AUTHOR]

High-flow nasal cannula oxygen therapy (HFNC) is recommended for patients with COVID-19. However, the increasing use of HFNC brings a risk of delayed intubation. The optimal timing of switching from HFNC to invasive mechanical ventilation (IMV) remains unclear. An effective predictor is needed to assist in deciding on the timing of intubation. Respiratory rate and oxygenation (ROX) index, defined as (SpO 2 /FiO 2) / respiratory rate, has already shown good diagnostic accuracy. Modified ROX (mROX) index, defined as (PaO 2 /FiO 2) / respiratory rate, might be better than the ROX index in predicting HFNC failure. The aim was to evaluate the predictive value of mROX for HFNC failure in patients with COVID-19. Severe or critical patients with COVID-19 treated with HFNC were enrolled in two clinical centers. Laboratory indicators, respiratory parameters, and mROX index at 0 h and 2 h after initial HFNC were collected. Based on the need for IMV after HFNC initiation, the patients were divided into an HFNC failure group and an HFNC success group. The predictive value of mROX index for IMV was evaluated by the area under the receiver operating characteristic curve (AUROC) and logistic regression analysis. We performed Kaplan–Meier survival analysis using the log-rank test. Sixty patients with COVID-19 (mean ± SD age, 62.8 ± 14.1 years; 42 patients were male) receiving HFNC were evaluated, including 18 critical and 42 severe cases. A total of 33 patients had hypertension; 14 had diabetes; 17 had chronic cardiac disease; 11 had chronic lung disease; 13 had chronic kidney disease; and 17 had a history of stroke. The AUROC of mROX index at 2 h was superior to that of other respiratory parameters to predict the need for IMV (0.959; p < 0.001). At the mROX index cutoff point of 4.45, predicting HFNC failure reached the optimal threshold, with specificity of 94% and sensitivity of 92%. Logistic regression analysis showed that 2-h mROX index < 4.45 was a protective factor for IMV (odd radio 0.18; 95% CI 0.05–0.64; p = 0.008). In the HFNC failure group, the median time from HFNC to IMV was 22.5 h. The 28-day mortality of the late intubation patients (≥ 22.5 h) was higher than that of the early intubation patients (< 22.5 h) (53.8% vs. 8.3%; p = 0.023). mROX at 2 h is a good early warning index of the need for IMV in patients with COVID-19 after HFNC initiation. Early intubation may lead to better survival in patients with 2-h mROX index < 4.45. [ABSTRACT FROM AUTHOR]

Pressure fluctuation is an important factor affecting the stability of rotating machinery. Electric submersible pumps (ESPs) are generally arranged in a multistage series structure, and its internal unsteady flow is extremely easy to propagate and develop in the lengthy flow passage, which brings about differences in the characteristics of pressure fluctuations in each stage. In contrast to the conventional method of processing pressure fluctuation signals, we propose a parameter called "energy flow density (EFD)" of pressure pulsation by analogy with the definition of wave intensity, in order to directly quantify the intensity of pressure fluctuations. Here, we study these pressure fluctuation characteristics using a typical three-stage ESP as the research object. We apply theoretical analysis, numerical simulation, and test verification. First, in comparisons between numerical predictions of pressure fluctuation and test results, the period, amplitude, and phase of pulsation curves are highly consistent, verifying the accuracy of the numerical method employed in this paper. Next, the mechanism underlying the pressure fluctuations and the characteristics of inter-stage interference are investigated through flow field analysis. Subsequently, the results of the evaluation of the pressure fluctuations based on EFD processing are compared with those obtained in the conventional way. The results are consistent in terms of characterizing the multistage ESP pressure fluctuation characteristics, but the conventional method does not reflect subtle differences due to inter-stage propagation and coupling. However, the EFD method combines the amplitudes of all signals and provides the intensity of pressure fluctuations directly, which reflects inter-stage differences. Our results provide a theoretical basis for improving the operational stability of ESPs connected in a multistage series and have practical engineering significance. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of the pulse width and amplitude on the scouring of sand beds by vertical submerged pulsed jets using a combination of experimental and numerical calculations. The reliability of the numerical calculations is verified through a comparison between the numerical simulations with the sedimentation scour model and the experimental data at a low pulse width T 2 of 0, with the result that the various errors are within 5%. The results show that the scour hole depth | h min | grows with the relative low pulse width T 3 throughout three intervals: a slowly increasing zone I, a rapidly increasing zone II, and a decreasing zone III, producing a unique extreme value of | h min |. The optimal scouring effect equation was obtained by analytically fitting the relationship curve between the pulse amplitude V and the relatively low pulse width T 3. Including the optimal T 3 and optimal duty cycle ƞ. The difference in the scour hole depth | h min | under different pulse amplitudes is reflected in the initial period F of the jet. With an increasing pulse amplitude, | h min | goes through three intervals: an increasing zone M, decreasing zone N, and rebound zone R. It is found that the scouring effect in the pulse jet is not necessarily always stronger with a larger amplitude. The results of the research in this paper can provide guidance for optimizing low-frequency pulsed jets for related engineering practices, such as dredging and rock-breaking projects. • Numerical simulations and experiments were combined to investigate pulsed jet scour. • The effect mechanism of pulse amplitude on the variation of scour hole depth was analyzed. • Models for the prediction of relative low pulse width with the inlet pulse amplitude have been developed. [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHWs) in the South China Sea (SCS) have prolonged impacts on local ecosystems and economies, and accurate projection of MHWs under future global warming is crucial for the high-quality development of local society. The future change in the spatial pattern of MHWs, however, is not clear despite the well-known overall intensification of MHWs. Here we find that the Coupled Model Intercomparison Project Phase 6 (CMIP6) models can effectively capture the main distribution of observed SCS MHWs, showing a uniform distribution of frequency and a "north high-south low" distribution of mean intensity and cumulative intensity. However, it is worth noting that the simulated center of long MHW duration is shifted to the southern SCS compared to the central SCS in observations. Under the Shared Socioeconomic Pathway 1–2.6 (SSP126) scenario, the increase in MHW cumulative intensity exhibits a double-center structure in the northern coastal region and southern SCS. This is primarily attributed to the large increase in frequency and mean intensity in the north, and an increase in duration in the south. Both the SSP245 and SSP585 scenarios project similar patterns of MHW intensification, but with larger magnitudes. The climatological distribution of the mixed layer depth (MLD), which is deeper in the south and shallower in the north, contributes to the spatial distribution of SCS MHW changes. The strong seasonal-mean sea surface temperature (SST) warming in the northern SCS, caused by enhanced solar radiation, also contributes to the intensification of MHW frequency and mean intensity in the northern region. [ABSTRACT FROM AUTHOR]

Many of the world's largest deltas are increasingly threatened by impact of climate change and human activities. The Changjiang (Yangtze River) is among the largest river, and its change of delta has received extensive attention. However, many studies covered smaller delta areas, which cannot reflect the changes of the entire delta region. Here, we present an assessment of the Changjiang (Yangtze River) mega-delta (CMD) using 60 years of bathymetric data covering the entire study area in order to gain clear insight into the comprehensive morphological changes in the Anthropocene. The net deposition rate decreased from 3.47 cm/year over the period 1954–1986 to 0.074 cm/year for the period 2005–2013 in the subaqueous-delta because of a dramatic decline in the sediment load. In particular, as the sediment load further decline due to the implementation of soil and water conservation engineering since 1980s, slight erosion occurred at a rate of −0.0019 cm/year during 1986–2002. However, the subaqueous-delta converted to a balanced state from one of slight erosion, and the depocenter moved southward between 2002 and 2013. Consequently, the morphological change of the CMD went through the following periods: fast accumulation from 1954 to 1986, and balanced accumulation/erosion during 1986–2013 (conservative state in1986–2002 and steady state in 2002–2013). Moreover, the subaerial delta of the Changjiang experienced continued progradation; the area of the subaerial delta increased from 14,857.74 km2 in 1974 to 16,039.03 km2 in 2013 (7.9% increase), with a net progradation rate of 29.53 km2/year; and the most pronounced progradation occurred at Chongming Island and the eastern parts of Nanhui. An important reason for these changes was land reclamation, deep-water channel projects, and shore protection, despite a marked decrease in the river sediment supply. In the future, whether the accumulation/erosion balance continues to be maintained will be an urgent research in the CMD. [ABSTRACT FROM AUTHOR]

Highlights • The original spatial pattern of the natural geographical attributes was changed by human activities. • Different ecosystem components have different responses to human activities. • The establishment of reserved areas has a positive effect on the protection of Marine biodiversity. Abstract Using the marine biological valuation method, we selected five ecosystem components, namely, phytoplankton, microzooplankton, macrozooplankton, macrobenthos, and nekton, to evaluate the marine biodiversity value of Jiangsu's offshore areas in 2006 (early-term coastal development) and 2014 (mid-term coastal development), and the impact of human activities on the values were analyzed based on the differences between the two time periods. In general, the biological value (BV) of the Jiangsu offshore area changed in the context of high-intensity human activities, disrupting the original spatial pattern of the natural geographical attributes indicated by the BV in 2006. From the perspective of various ecosystem components, the impact on macrobenthos is long-lasting and significant, the impact on plankton is temporary and recoverable, and the presence of offshore structures leads to the formation of new habitats that attract new species and more predators (fishes), with the BV of nekton in the radial sand ridge area being higher than that in other marine areas. The results of our approach confirm the importance of areas that were previously identified for protection (particularly in the central regions). Our results also highlight the value of currently unprotected sites, mainly in the northern and southern regions. Highlighting the impact of high-intensity human activities on the BV of Jiangsu lays a foundation for developing future marine spatial plans and provides a scientific reference and basis for administrative departments to develop marine management decisions. [ABSTRACT FROM AUTHOR]

We examined the source-to-sink sediment transport processes from the Changjiang River to the estuarine coastal shelf area by analyzing the clay mineral assemblages in suspended sediment samples from the Changjiang River catchment and surface samples from the estuarine coastal shelf area following the impoundment of the Three Gorges Dam (TGD) in 2003. The results indicate that the clay mineral compositions throughout the study area are dominated by illite, with less abundant kaolinite and chlorite and scarce smectite. The clay minerals display distinct differences in the tributaries and exhibit obvious changes in the trunk stream compared with the periods before 2003, and the source of sediment has largely shifted to the mid- to lower reaches of the river after 2003. Spatially, the clay mineral assemblages in the estuarine area define two compositionally distinct provinces. Province I covers the mud area of the Changjiang River estuary and the Zhe-Min coastal region, where sediment is primarily supplied by the Changjiang River. Province II includes part of the Changjiang River estuary and the southeastern portion of the study area, where the sediment is composed of terrestrial material from the Changjiang River and re-suspended material from the Huanghe River carried by the Jiangsu coastal current. Moreover, the other smaller rivers in China (including the Oujiang and Minjiang rivers of mainland China and the rivers of West Taiwan) also contribut sediments to the estuarine and inner shelf areas. In general, the clay mineral assemblages in the Changjiang River estuarine area are have mainly been controlled by sediment supplied from upstream of the Changjiang River tributaries. However, since the completion of the TGD in 2003, the mid- to downstream tributaries have become the main source of sediments from the Changjiang catchment into the East China Sea. These analyses further demonstrate that the coastal currents and the decrease in the sediment load of the river have the greatest impacts on the distribution and transport of clay minerals assemblages in the sediments. [ABSTRACT FROM AUTHOR]

The water discharge and sediment load of rivers are changing substantially under the impacts of climate change and human activities, becoming a hot issue in hydro-environmental research. In this study, the water discharge and sediment load in the mainstream and seven tributaries of the Yangtze River were investigated by using long-term hydro-meteorological data from 1953 to 2013. The non-parametric Mann-Kendall test and double mass curve (DMC) were used to detect trends and abrupt change-points in water discharge and sediment load and to quantify the effects of climate change and human activities on water discharge and sediment load. The results are as follows: (1) the water discharge showed a non-significant decreasing trend at most stations except Hukou station. Among these, water discharge at Dongting Lake and the Min River basin shows a significant decreasing trend with average rates of − 13.93 × 10 8 m 3 /year and − 1.8 × 10 8 m 3 /year ( P < 0.05), respectively. However, the sediment load exhibited a significant decreasing trend in all tributaries of the Yangtze River. (2) No significant abrupt change-points were detected in the time series of water discharge for all hydrological stations. In contrast, significant abrupt change-points were detected in sediment load, most of these changes appeared in the late 1980s. (3) The water discharge was mainly influenced by precipitation in the Yangtze River basin, whereas sediment load was mainly affected by climate change and human activities; the relative contribution ratios of human activities were above 70% for the Yangtze River. (4) The decrease of sediment load has directly impacted the lower Yangtze River and the delta region. These results will provide a reference for better resource management in the Yangtze River Basin. [ABSTRACT FROM AUTHOR]