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Facing the need for transdisciplinary research to promote ecological restoration that achieves both social and ecological benefits, research on past restoration efforts that have directly or indirectly contributed to regional or national sustainable development warrants reassessment. Using China as an example, in this review, we address three basic research questions that can be summarized as follows: ecological restoration—of what, for whom and to what purpose? Accordingly, a 'landscape pattern—ecosystem service—sustainable development' co-evolutionary framework is proposed here to describe landscape-scale ecological restoration and its impact on landscape patterns and ecological processes, ecosystem services for human well-being, sustainable livelihoods and socioeconomic development. From the strategic pattern of national ecological security to the pattern of major projects to protect and restore major national ecosystems, the spatial pattern of China's ecological restoration is more geographically integrative. From major function-oriented zoning to systematic ecological protection and restoration, and for the purpose of achieving the Beautiful China Initiative, there are three stages of ecosystem services management: classification, synergy and integration, respectively. The difference in geographic processes should be considered in the key requirements of ecological restoration for China's five national strategies for regional sustainable-development strategies. Deepening understanding of the relationship between humans and nature in different geographical contexts is a scientific prerequisite to support policymaking related to ecological restoration. To promote greater harmony between humans and nature, we propose four important research directions: (i) understanding coupling processes among key components, (ii) identifying ecosystem service flows, (iii) evaluating social-ecological benefits and (iv) supporting adaptive management for regional sustainable development. [ABSTRACT FROM AUTHOR]

Lakes and lake sediments are significant components of the global carbon (C) cycle, and may store very large amounts of organic matter. Carbon sequestration in lakes is subject to substantial temporal and spatial variation and may be strongly affected by human activities. Here, we report accumulation rates (AR) of organic C (OC), total nitrogen (TN) and total phosphorous (TP), and investigate their responses to anthropogenic impact over the past 150 years by analyzing 62 sediment cores from 11 shallow lakes in the Songnen Plain, northeast China. From the center of each of the lakes, we selected one master core for age determination by 210Pb and 137Cs radioisotopes. The contents of OC, TN, TP, dry bulk density and mass specific magnetic susceptibility were then determined for all cores. The regional OCAR, TNAR and TPAR up-scaling from the multiple cores yielded mean values of 51.63 ± 15.13, 2.50 ± 0.98, and 0.90 ± 0.21 g m−2 yr−1, respectively. Nutrient AR in the studied lakes increased by a factor of approximately 2 × from the middle 19th century to the 1950s, and approximately 5 × after the 1950s. Elemental ratios show that the increase in OCAR is mainly the result of C autogenesis from the growth of aquatic plants stimulated by agricultural intensification, including increased chemical fertilizer application and farmland expansion. Significantly enhanced nutrient burial by these lakes after the 1950s resulted from increased anthropogenic impacts in northeast China. More sustainable agricultural practises, including a decrease in P fertilizer use, would result in a lowering of OCAR, TNAR and TPAR in the future. Image 1 • Accumulation rates of C/N/P were reconstructed through 11 age-dated lake sediments in NE China. • Mean accumulation rates for organic C, total N and total P are ca. 52, 2.5, and 0.9 g m−2 yr−1, respectively. • Nutrient accumulation rates increased ∼2 × from the middle 19th century to the 1950s, and ∼5 × after 1950. • Enhanced nutrient burial in these lakes after the 1950s are due to increased anthropogenic impacts. • More sustainable agricultural practises used during the last years would result in lower accumulation rates of C/N/P. Anthropogenic impacts increased ∼2 × nutrient burial in the Songnen Plain lakes of northeast China from the middle 19th century to the 1950s, and ∼5 × after 1950. [ABSTRACT FROM AUTHOR]

Understanding the transient dynamics of interlinked social-ecological systems (SES) is imperative for assessing sustainability in the Anthropocene. However, how to identify critical transitions in real-world SES remains a formidable challenge. In this study, we present an evolutionary framework to characterize these dynamics over an extended historical timeline. Our approach leverages multidecadal rates of change in socioeconomic data, paleoenvironmental, and cutting-edge sedimentary ancient DNA records from China's Yangtze River Delta, one of the most densely populated and intensively modified landscapes on Earth. Our analysis reveals two significant social-ecological transitions characterized by contrasting interactions and feedback spanning several centuries. Initially, the regional SES exhibited a loosely connected and ecologically sustainable regime. Nevertheless, starting in the 1950s, an increasingly interconnected regime emerged, ultimately resulting in the crossing of tipping points and an unprecedented acceleration in soil erosion, water eutrophication, and ecosystem degradation. Remarkably, the second transition occurring around the 2000s, featured a notable decoupling of socioeconomic development from ecoenvironmental degradation. This decoupling phenomenon signifies a more desirable reconfiguration of the regional SES, furnishing essential insights not only for the Yangtze River Basin but also for regions worldwide grappling with similar sustainability challenges. Our extensive multidecadal empirical investigation underscores the value of coevolutionary approaches in understanding and addressing social-ecological system dynamics. [ABSTRACT FROM AUTHOR]

The 10Be record in laminated travertines is a potential proxy for reconstructing past solar activity down to the annual scale; however, correcting for the potential influence of climatic or environmental variations remains challenging. Here, we present an annually resolved 10Be record using travertines from Baishuitai, China, covering the period from 1510 to 1701 CE, along with environmental proxies, to evaluate climatic influences and implement corrections to accurately reconstruct solar activity. We demonstrate that the 10Be deposition in travertines exhibits two environmental impacts: the transport efficiency of atmospheric 10Be into travertine and the additional 10Be inflow from overland flow associated with rainfall. We show that these impacts can be corrected based on iron and potassium contents. The resulting corrected record agrees with ice‐core and tree‐ring records, demonstrating the feasibility of using such carbonate sediment 10Be records to reconstruct past solar activity. Plain Language Summary: The travertine 10Be record has great potential as a proxy for high‐resolution reconstruction of past solar activity; however, the methodology for correcting the potential influence of climatic or environmental variations has not been fully established. This study presents a new high‐precision annual 10Be record using travertines from Baishuitai, China, covering the period 1510–1701 CE, together with records of environmental proxies, allowing us to evaluate the climatic influences and establish a methodology for correcting them to facilitate accurate solar activity reconstruction. We find that there are two environmental impacts on the deposition of 10Be in travertine: one is the transport efficiency of atmospheric 10Be into travertine, and the other is the additional 10Be inflow from the runoff following rainfall events, and we use iron (Fe) and potassium (K) contents to correct these impacts. The corrected travertine 10Be record exhibits good agreement with ice‐core 10Be and tree‐ring 14C records, supporting that the 10Be record in Baishuitai travertine reliably reflects the atmospheric radionuclide production rate as regulated by solar activity. This result demonstrates the feasibility of using such carbonate sediment 10Be records to reconstruct annual solar activity and suggests the possibility of extending the annual records further back in time than previously obtained. Key Points: A high‐precision annual record of travertine 10Be from 1510 to 1701 CE was obtained to assess its potential as a proxy for solar activityClimatological and environmental impacts on 10Be deposition were found to be correctable based on the content of trace elementsThe travertine 10Be record corrected for climatological impacts reasonably preserves the decadal and centennial‐scale solar cycles [ABSTRACT FROM AUTHOR]

Dynamics of the terrestrial water surface impact hydrological connectivity. Compared with traditionally deployed water surface parameters, changes in the water-boundary more effectively account for the dynamics of water surface and depth resulting from hydrological variations. However, previous studies of hydrological connectivity generally applied only connectivity length or width parameters using the center line of the water body and therefore fail to fully capture the impact of water boundary dynamics. In this study, optimized water body extraction indices based on data obtained from remote sensing imagery are used to develop a novel metric that indicates water surface boundary dynamics and reveal surface hydrological connectivity changes in the Yangtze River Delta from 1990 to 2020. Detailed inter-annual and seasonal changes in the evolution of water body boundaries from a water surface perspective indicate an overall decline in hydrological connectivity against the background of climate change, increased urbanization, and dam construction. The declining trend in connectivity occurs in three phases, viz. from 1990 to 2003, a gradual decline is exhibited but with a very marked degree of inter-seasonal variability; between 2003 and 2012, connectivity remains relatively constant but with a reduced amplitude between seasons; further reductions in the magnitude of seasonal variations characterize the third phase, to 2020. Meanwhile, the stability of hydrological connectivity, indicated by the coefficient of variation, also exhibits marked spatial heterogeneity. Parts of the delta with more tributaries, including the Huaihe and southeastern basins, have lower stability (7.33 and 6.59, respectively) than the Yangtze basin (6.22). This study presents a novel metric to achieve greater precision in the monitoring of hydrological connectivity. Such information can be harnessed to improve regional ecological and water resource management. [ABSTRACT FROM AUTHOR]

Archeological evidence from loess sediments from Shangchen on the southeastern Chinese Loess Plateau indicates a suspension of hominin occupation around the time of the early mid‐Pleistocene climate transition, prompting a re‐assessment of climate‐vegetation‐hominin interactions. Loess deposits with in situ lithic records cover the period of hominin occupation and reveal four distinct climate‐vegetation periods (2.1–1.8, 1.8–1.26, 1.26–0.9, and 0.9–0.6 Ma). Major oscillations in climate superimposed upon an aridification trend and an expansion of C4 herbaceous vegetation from about 1.26 Ma may have driven early humans to move to more hospitable locations in the region. Comparison with the record at Nihewan indicates that large‐scale climate oscillations induced disparate hominin responses due to distinctive local environmental conditions. Plain Language Summary: A combination of several lines of evidence suggests that changes in climate and their impacts on the availability of food and shelter from around 1.26 million years ago may have driven the dispersal of early humans from the southeastern Chinese Loess Plateau to more hospitable environments elsewhere in the region. Key Points: Pleistocene temperature, rainfall, and C4 plants ratios are quantitatively reconstructed from the Shangchen loess deposits with artifactsHigh climate variability, C4 plants expansion and aridification suspended hominin occupation at Shangchen during the early mid‐Pleistocene climate transitionHominins responded differently to large‐scale climate oscillations depending on distinctive local environmental conditions [ABSTRACT FROM AUTHOR]

Using geological evidence to extend the history of typhoon activity beyond the instrumental period and understand the possible linkage between future climate change and increasing storm intensity is of great significance in preparing for coastal risks in a warming world. In this study, an extreme storm event that occurred on the southern Yangtze coast, East China, during the latter stage of Neolithic Liangzhu Culture were estimated based on sedimentary records and numerical modeling. We first investigated the spatial distribution of peat layers formed during the time of the Liangzhu Culture to produce a high-resolution map of the paleo-coastline of the Ningbo Plain. Inverse modeling using the grain size of storm deposits recovered at the end of Liangzhu Culture at the Neolithic Yushan site was applied to calculate the instantaneous water level including wave run-up and storm surge caused by the extreme event. Numerical simulations of multiple typhoon scenarios combined with precipitation and sea-level rise constrained by the paleo-coastline and paleo-topography were then used to estimate the storm surge and inundation on the coast of Hangzhou Bay. Through comparison of results between the inverse model and numerical simulations, we infer that the intensity of the storm recorded at the Yushan site was likely greater than any typhoon in the local instrumental records and that the storm deposits were formed by a Super Typhoon, which moved close to or made landfall directly on the southeast coast of Hangzhou Bay. Our modeling further suggests that the extreme storm event was coupled with an abrupt relative sea-level rise at ca. 4.5 cal kyr BP, which indicates a warmer west Pacific Ocean at that time. • Sand ridge deposits provide evidence of a major paleostorm at ca 4.5 ka. • Maximum wave run-up height and storm surge of >20 m calculated by the reverse model. • Deposits were formed by a Super Typhoon under the condition of sea-level rise. • Increased frequency of extreme storm events coupled with rapid sea-level rise [ABSTRACT FROM AUTHOR]

Increasing demand for land resources at the coast has exerted immense pressure on vulnerable environments. Population and economic growth in coastal cities have combined to produce a scarcity of suitable space for development, the response to which has frequently been the reclamation of land from the sea, most prominently in China. Urbanization is a key driver of such changes and a detailed investigation of coastal land reclamation at the city scale is required. This study analyzed remote sensing imagery for the period 1990 to 2018 to explore the trajectories of coastal land reclamation in nine major urban agglomerations across the three largest deltas in China using the JRC Global Surface Water (Yearly Water Classification History, v1.1) (GSW) dataset on the Google Earth Engine platform. The results are considered in the context of major national policy reforms over the last three decades. The analysis reveals that total land reclaimed among nine selected cities had exceeded 2800 km2 since 1984, 82% of which occurred after 2000, a year following the enactment of China's agricultural 'red line' policy. Shanghai exhibited the greatest overall area of land extension, followed by Ningbo and Tianjin, especially in the period following the privatization of property rights in 2004. In analyzing annual trends, we identified the developmental stages of a typical coastal reclamation project and how these vary between cities. Scrutiny of the results revealed voids in nighttime light satellite data (2014–2018) in some localities. Although these voids appeared to be characterized by construction, they were occupied by vacant buildings, and were therefore examples of so-called "ghost cities." In China, as elsewhere, continual land reclamation needs to be considered in relation to, inter alia, sea level rise and land subsidence that pose significant challenges to the vision of sustainable urban development in these three deltaic megacities. [ABSTRACT FROM AUTHOR]

Building height is a crucial variable in the study of urban environments, regional climates, and human-environment interactions. However, high-resolution data on building height, especially at the national scale, are limited. Fortunately, high spatial-temporal resolution earth observations, harnessed using a cloud-based platform, offer an opportunity to fill this gap. We describe an approach to estimate 2020 building height for China at 10 m spatial resolution based on all-weather earth observations (radar, optical, and night light images) using the Random Forest (RF) model. Results show that our building height simulation has a strong correlation with real observations at the national scale (RMSE of 6.1 m, MAE = 5.2 m, R = 0.77). The Combinational Shadow Index (CSI) is the most important contributor (15.1%) to building height simulation. Analysis of the distribution of building morphology reveals significant differences in building volume and average building height at the city scale across China. Macau has the tallest buildings (22.3 m) among Chinese cities, while Shanghai has the largest building volume (298.4 108 m3). The strong correlation between modelled building volume and socio-economic parameters indicates the potential application of building height products. The building height map developed in this study with a resolution of 10 m is open access, provides insights into the 3D morphological characteristics of cities and serves as an important contribution to future urban studies in China. • A first country-wide 10 m building height map for China. • Shading index is the most important variable in estimating building height. • High degree of building height accuracy with RMSE of 6.1 m. [ABSTRACT FROM AUTHOR]

Coastal societies are known to be vulnerable to sea-level rise. However, here we report the occurrence of salt manufacturing in the archaeological record of an island of East China that reveals an adaptation strategy by a prehistoric coastal society to sea-level rise through an interdisciplinary study of archaeology and stratigraphy. Archaeological findings and observations of marine microfossils and alkaline earth metals in sediment sequences, together with radiocarbon and optically stimulated luminescence (OSL) dating, reveal that the site was initially occupied at ca. 2900 BCE as an island village with multiple subsistence strategies including hunting, fishing, and stone-tool making associated with the formation of a freshwater dominated coastal plain. Seawater inundation induced by relative sea-level rise occurred at the site at ca. 2400 BCE when Neolithic people constructed elevated mounds and developed specialized sea-salt manufacture in the sheltered tidal flat environment on the island. Evidence from the foraminiferal assemblage suggests that salty soil was scraped from the surface of the adjacent tidal flats and waste material was dumped around the artificial mounds. Micro-structures of the foraminiferal fossils further indicate that these salty soils were air-dried before brine enrichment to produce high-quality salt. Such an economic shift from multiple subsistence into specialized sea-salt manufacture on the island stands in striking contrast to the contemporaneous abandonment of numerous Liangzhu settlements on the adjacent mainland due to coastal flooding. We suggest that prehistoric sea-salt manufacture on the East China coast signifies the resilience of coastal societies in facing the challenge of sea-level rise through exploitation of geographical advantages and marine resources. • Daxie Island was occupied by Neolithic people practicing multiple subsistence at 2900 BCE. • Coastal flooding at 2400 BCE terminated the occupation, although the site was not abandoned. • Sea-salt industry developed associated with the construction of elevated mounds. • The sea-salt making procedure included air-drying and leaching salty soil, and brine-boiling. • Such cultural adaptation prompts a re-assessment of post-Liangzhu archaeology. [ABSTRACT FROM AUTHOR]

The recent substantial expansion of human activities in northeast (NE) China has resulted in increased emission of environmental pollutants. Longer-term records of such environmental pollutants provide a benchmark against which it is possible to evaluate the nature, extent and timing of anthropogenic environmental changes. Based on measurements of mercury (Hg) concentrations and accumulation rates in 11 lake sediment cores from the Songnen Plain in NE China, we here present a reconstruction of the historical deposition of Hg as an indicator of the changing scale of human impact. The results demonstrate an increasing trend of Hg concentration, concurrent with elevated anthropogenic emissions, beginning from the early 1900s, accelerating through the mid-1950s and slightly decreasing from the late 1990s onwards. The increase in anthropogenic Hg coincides with the reform and opening up of China, which precipitated social and economic transformation, and rapid industrial and economic growth. Measurements of the Hg enrichment factor in all the cores enables identification of the anthropogenic contribution to Hg accumulation. The geoaccumulation index indicates that the lakes are in general moderately polluted by Hg. The historical trend of Hg accumulation rate parallels the temporal progression of biomass burning and fossil fuel consumption in the region. The findings elucidate the extent of anthropogenic pollution in the Anthropocene and underline the importance of identifying Hg sources to reduce emissions and guide the implementation of effective mitigation strategies. [Display omitted] • Reconstruction of historical Hg deposition in sediment cores from 11 lakes in NE China. • Lakes are moderately polluted by Hg and indication of anthropogenic Hg input. • Declining trend in Hg in the recent decades, consistent with emission reductions. • Hg AR parallels the temporal progression of biomass burning and fossil fuel consumption. [ABSTRACT FROM AUTHOR]

Understanding coastal flooding processes in response to centennial-scale sea-level rise is essential in preparing for the challenge of present-day global warming. Mid-Holocene sea-level rise induced widespread coastal flooding along the East China coast and precipitated the collapse of the Neolithic Liangzhu Culture, the earliest known prehistoric state in East Asia. This paper presents multi-proxy analyses of sedimentology, grain size, total organic carbon (TOC), and alkaline-earth metals extracted by acetic acid (HAc) of a dated sediment core, ZK07, collected from Liangzhu City, with the aim of revealing the detailed progression of coastal flooding phases and the response of prehistoric people at the end of the associated Liangzhu Culture. A three-step succession of coastal flooding processes between ca. 4.6–4.3 cal kyr BP, brought about by relative sea-level rise, is evident in core ZK07. Initially, an increase in the local water level in response to the first phase of sea-level rise is indicated by a gradual increase in TOC at ca. 4630 cal yr BP. Subsequently, at ca. 4520 cal yr BP, a second phase of increased local water-level, consistent with further sea-level rise and salinity intrusion, is suggested by higher Sr concentrations accompanied by a sharp increase in TOC. Thirdly, at ca. 4480–4315 cal yr BP, low TOC content, high - but strongly fluctuating - Sr and Ba concentrations and coarser sediment grain size are all indicative of coastal inundation caused by both storm surges and river flooding associated with typhoon events that correspond with a concurrent phase of accelerated sea-level rise. Considering the evidence of cultural deposits preserved at Liangzhu City, it appears that the Liangzhu people were forced to respond rapidly to the inundation by abandoning the city at ca. 4480 cal yr BP. We suggest that relative sea-level rise and coastal flooding at the terminal stage of the Liangzhu Culture was the regional response to global climate warming and eustatic sea-level rise at that time. Given evidence that a contemporaneous cultural transition took place in the lower Yellow River basin, we further propose that global climate change around 4.5 cal kyr BP had a widespread impact on Neolithic cultural evolution in East China. Furthermore, the rise in local water levels and associated salinity intrusions may be considered as an early warning signal in monitoring future coastal flooding risk. • A three-step succession of coastal flooding was recognized at the end of Liangzhu Culture. • Rise in local water level and salinity intrusion could be early warning of coastal flooding. • Global climate warming and eustatic sea-level rise at ca. 4.5 ka was the major mechanism. • Contrasting Neolithic cultural evolution occurred in the lower reaches of two large rivers in East China. [ABSTRACT FROM AUTHOR]

Reconstructing the long-term history of tropical cyclones is key to understanding their driving mechanisms and to enable better predictions of future extreme storm events. However, the available history of typhoons, based on sedimentary records in the northwest Pacific basin, remains very limited. In this study, we conducted multi-proxy analyses of sedimentary profiles collected from a chenier ridge on the north bank of Hangzhou Bay, East China. We applied evidences from the lithology, grain size, and marine micro-fossils on sediments in these profiles, dated using OSL and AMS 14C, to reveal the mid-Holocene sedimentary environmental evolution and obtain records of extreme storm events. The lithology and foraminiferal assemblages indicate an aggradational succession from intertidal to supratidal flats incorporating two layers of storm deposits preserved in the chenier ridge. The lower layer of storm deposits was formed in the intertidal flats at ca. 6.0 cal. kyr BP, while the upper layer was formed in the supratidal flats at ca. 5.2–4.9 cal. kyr BP. The storm deposits are characterized by coarsened grain size and the prevalence of allochthonous foraminiferal species, including E. advenum , A. annectens , and A. compressiuscula which occur in the inner and middle shelf of East China Sea. The extreme storm events at ca. 6.0 and 5.2–4.9 cal. kyr BP recorded at the chenier ridge have also been described at different sites on the southeast coast of Hangzhou Bay. Together with previously reported storm deposits at ca. 4.5 cal. kyr BP, we suggest that these mid-Holocene extreme typhoon events on the East China coast resulted from global climate changes driven by solar irradiance. • Chenier ridge sediments reveal aggradational succession from intertidal to supratidal flats. • Inner and middle shelf foraminfera provide evidence of multiple mid-Holocene storms. • Extreme storm events occurred on the East China coast at 6.0, 5.2–4.9, and 4.5 cal. kyr BP. • Sedimentary sequences provide analogue of such events under global climate change. [ABSTRACT FROM AUTHOR]

Xinjiang, northwestern China, has the largest area of sandy desert landscapes in the northern hemisphere mid-latitudes and is known to be subject to so-called sandy desertification. Longer-term records of changes in the distribution of sandy desert landscapes are required to develop a more comprehensive understanding of mechanisms underlying their spatial and temporal dynamics. Here, we integrate a diverse range of data sources, including historical maps, documentary accounts, government statistics, remote sensing data, global climate reanalysis data, and field reconnaissance data, to reconstruct 110 years of spatial variations in sandy desert distribution in Xinjiang. Our results show that, overall, there has been a 22.3% reduction in the area of sandy desert in Xinjiang over the past 110 years. Cross-wavelet and linear regression analyses reveal that vegetation changes are the major determinants of sandy desertification during this period and that, in contrast to previous studies in the region, aeolian factors and human-induced degradation are less important drivers than previously reported. Ecosystem management has markedly constrained sandy desert expansion even against a background of population increase. The suggested comprehensive approach may be useful in improving understanding of sandy desert dynamics and associated desertification forcing mechanisms in arid and semiarid regions globally. • An integrated mapping and statistical approach is applied to investigate sandy desertification in Northwestern China. • The region experienced an overall reduction in the area of sandy desert since 1909 by ecosystem management. • Vegetation cover changes by either climate or human intervention are the major determinants of sandy desert dynamics. [ABSTRACT FROM AUTHOR]

Muddy coasts downdrift of large river mouths trap fine-grained sediments supplied from these rivers and have provided important settlement sites for prehistoric people, although the evolutionary history of such environments has not been well described. In this study, we integrate multi-proxy analyses (lithology, particle size, sedimentary structure, bioturbation, microfossil, and AMS 14C) on two new sediment cores (CC and ZF) from the Ningbo Plain, southeast of Hangzhou Bay, east China, with results from previous studies to explore the early to mid-Holocene sedimentary history of the palaeo-Ningbo Bay in response to post-glacial sea-level rise. The results show that the early to mid-Holocene stratigraphy in core CC was characterized by a muddy embayment succession before 7.3 cal kyr B.P. and an aggradational tidal flat to coastal marsh succession after that time. Rapid sediment accumulation occurred before ca. 7.7 cal kyr B.P. and at 7.3–7.2 cal kyr B.P., whereas periods of reduced sediment supply are recorded between 7.7 and 7.3 cal kyr B.P. and after 7.2 cal kyr B.P. At site ZF, in contrast, only sediments of coastal freshwater marsh overlay the last glacial stiff muds after ca. 7.5 cal kyr B.P. We suggest that the sheltered embayment favoured trapping of the fine-grained sediments during the early to mid-Holocene, while geometric changes of the bay in response to a phase of accelerated sea-level rise at ca. 7.7 cal kyr B.P. resulted in a reduced sedimentation rate and increased tidal energy. Abundant, large, and diverse (0.5–1.0 cm wide, 5–24 cm long) vertical burrows are present in core CC during 8.9–7.9 cal kyr B.P. and the trace fossils declined abruptly at 7.9 cal kyr B.P. We suggest this may have been induced by the exploitation of seafood by Neolithic people settled in the sheltered embayment, as supported by archaeological remains found at the Neolithic site. Rapid progradation of tidal flats and coastal marsh occurred since ca. 7.2 cal kyr B.P. in the palaeo-bay, which may reflect a response to a stable sea level after that time. The development of a thick early to mid-Holocene sediment sequence in the palaeo-Ningbo Bay and its relationship to sea-level changes indicate that such muddy embayments downdrift of large river mouths should be considered important in reconstructing the Holocene depositional system of the adjacent coast. • A thick sequence of embayment mud was deposited during the early to mid-Holocene. • Early Holocene high deposition rate contrasts with reduced sedimentation in the adjacent large river mouth. • Abrupt decrease in accumulation of trace fossils at 7.9 ka. • Increased tidal energy is linked to coastal geometric change due to sea-level rise at 7.6 ka. [ABSTRACT FROM AUTHOR]

In recent years, atmospheric PM2.5 pollution in China has become increasingly severe and exploring the relationships among its influencing factors is important in the prevention and control of air pollution. Although previous studies have identified complexity in variations in PM2.5 concentrations and recognized the interaction of multiple factors, little quantitative information is available on the evolution of the relationships among these factors, their spatial heterogeneity, and the multiscale interactions between them. In this study, geographical detector and multiscale geographically weighted regression models have been used to explore the multiscale interactions among natural and socioeconomic factors and PM2.5 concentration in China over the period 2000–2015. The results indicate that the relationship between natural factors and PM2.5 concentration is stronger than that for socioeconomic factors. The type of interaction between each factor is dominated by bivariate and nonlinear enhancement, exhibiting strong interactions between natural factors and anthropogenic factors. Although the effect of each factor on PM2.5 is complex, the relative influence of both human activities and social factors is shown to have gradually increased over time and population, agriculture, urbanization, and socioeconomic activities in general make important contributions to PM2.5. In addition, the scale of effects related to natural factors is smaller and more stable compared to the influence of human activities during the period 2000-2015. There are significant differences in the way natural factors and socioeconomic factors affect PM2.5, and there is strong non-stationarity of spatial relationships. Factors associated with topography, vegetation (NDVI), climate (temperature), natural sources, and agricultural activity are shown to be important determinants of PM2.5 across China and warrant significant attention in terms of managing atmospheric pollution. The study demonstrates that spatial differences in the direction, intensity, and scale of each factor should be accounted for to improve prevention and control measures and alleviate regional PM2.5 pollution. [ABSTRACT FROM AUTHOR]

The history and underlying mechanisms of extreme typhoon events during the Holocene on the east China coast are poorly resolved. This study presents an analysis of the chronology, sedimentology, and organic and alkaline-earth metal geochemistry of a profile (T0103W) collected from the Neolithic Xiawangdu site on the Ningbo Plain, east China coast. Through comparison with the chronology and palaeontology of a second profile from the same site, a coastal, tidally influenced fluvial setting is identified as the geomorphological environment which formed at ~5600 cal. yr BP in the context of a stable or falling relative sea level. Infilling or lateral migration of the tidal river occurred along with the outbuilding of the coastal alluvial plain during the Neolithic occupation. Two periods of salinity intrusion are identified, at ~5310–5145 and 4575–4330 cal. yr BP respectively, as indicated by the increase in Sr concentration and Sr/Ba ratios. Based on our multiproxy analysis, we suggest that frequent extreme typhoon events occurred during both periods. In response to the flooding, the Neolithic people either abandoned the low-lying land close to the river channel or retreated to dwellings constructed on earth mounds. The reconstructed history of extreme typhoon incursions on the east China coast is distinct from those of the South China Sea and southwestern Japan and reflects the complexity of typhoon tracks in the northwest Pacific basin in response to fluctuating sea level and climate change. • A tidally influenced fluvial setting formed associated with sea level regression 5600 years ago. • Extreme typhoon events occurred frequently during 5310–5145 and 4575–4330 cal. yr BP. • Typhoon strikes on the east China coast vary dynamically in response to the sea level and climate change. [ABSTRACT FROM AUTHOR]