The dispersal of prehistoric agricultural cultures onto the Tibetan Plateau and their adaptation to its extreme environments remain key scientific questions. The western Sichuan Plateau, located on the eastern margin of the Tibetan Plateau, served as a critical corridor for the spread of agriculture, yet the subsistence strategies together with the degree of sedentism among early Neolithic populations in this region remains unclear. The charcoal analysis from archaeological sites can well reveal the strategies of human wood gathering, indirectly reflecting the intensity of past human activities. The Konglongcun site ((sic) *4 +/- 1E) (ca. 5500-4800 cal. BP)-one of the earliest millet-farming Neolithic sites on the western Sichuan Plateau-provides an opportunity to investigate changes in wood exploitation and human activity through taxonomic identification, diameter estimation, and decay-index analysis of charcoal remains. The study findings indicated that Konglongcun inhabitants primarily adopted a local procurement strategy, exploiting dominant regional taxa, such as Abies sp., Pinus sp., and Acer sp. Climate reconstruction based on the coexistence approach suggested warmer and wetter conditions during the site's occupation than the present conditions, favoring thermophilic millet cultivation. The late phase showed a significant increase in the use of fresh wood, larger collected wood diameters, and a stronger preference for exploiting Pyrus sp. as fresh twigs than in the early phase, implying intensified agricultural activity and great sedentism. This study presents the first systematic evidence of wood exploitation by early Neolithic populations on the eastern Tibetan Plateau, offering new insights into how agricultural communities adapted to high-altitude environments during their expansion onto the plateau.

As the cradle of the Hemudu Civilization, the Ningshao Plain underwent substantial vegetation change during the Holocene, influenced by climatic fluctuations, sea-level changes, and anthropogenic activities. Understanding long-term vegetation responses to environmental dynamics is crucial for assessing ecosystem resilience under future climate scenarios. High-resolution pollen records from the HMD13 core in the Yaojiang Valley are used here to reconstruct early-mid Holocene vegetation change, with particular attention to biodiversity patterns and rates of turnover. The study reveals a number of important insights as follows: (1) During 8600-8400 cal yr BP, algal indicators suggest a sea-level rise near the study area, followed by a second phase of marine influence between 7800-7300 cal yr BP. (2) Between 7900-7100 cal yr BP, vegetation shifted from mixed forest dominated by deciduous oaks and pines to subtropical evergreen-deciduous broad-leaved forest dominated by evergreen oaks. (3) After 7100 cal yr BP, arboreal pollen declined and Poaceae (>38 mu m) and charcoal concentrations increased, reflecting intensified human activity. However, between 5900-5500 cal yr BP, Poaceae (>38 mu m) decreased sharply, possibly due to extreme climatic events such as floods. (4) Rates of vegetation change were primarily climate-driven prior to 7100 cal yr BP, peaking between 7100-6000 cal yr BP before gradually declining. Vegetation diversity also decreased following the emergence of the Hemudu culture. (5) Strong positive correlations are observed among vegetation change rate, diversity indices, and arboreal pollen percentage, while Poaceae (>38 mu m) pollen shows a negative correlation.

Dryland landscapes are highly sensitive to climatic variability and anthropogenic disturbance, yet sedimentary records capable of resolving their responses during the late Holocene-Anthropocene transition remain scarce. Here, we investigate nebkha deposits from the Mu Us dune field, north-central China, as novel archives of environmental and landscape change over the past similar to 120 years. A robust chronological framework for two nebkha profiles was established by integrating radionuclide dating (Cs-137 and Pu239+240), luminescence constraints, and Bayesian age-depth modelling. Multi-proxy analyses of grain size, magnetic susceptibility, and geochemical tracers were conducted to evaluate climatic and anthropogenic influences, supported by climate simulations and independent proxy reconstructions. The results reveal pronounced decadal-scale variability, with coarser sediments during 1900-1910, 1930-1940, and 1970-2000 CE, and finer sediments around similar to 1920, similar to 1950, and after similar to 2000 CE. Heavy metals and magnetic susceptibility peak around similar to 1950 CE, whereas black carbon is elevated around similar to 1920 CE. Beyond this variability, the nebkha records suggest a shift in the relative importance of climatic and anthropogenic influences around the 1970s. Before this transition, human disturbance, including land-use change and warfare-related impacts, appears to have exerted a stronger influence on surface stability and aeolian dynamics. After the 1970s, reduced direct human disturbance may have allowed climatic signals to be more clearly expressed in the nebkha records, as reflected by sediment fining associated with declining near-surface wind speeds after similar to 2000 CE. These findings indicate that nebkha sediments integrate climatic and anthropogenic signals and provide valuable decadal-scale archives of landscape evolution in dryland regions.

The accumulation of microplastics in surface soils and sediments has raised significant concerns due to their potential environmental risks. Conventional quantitative methods for microplastics often require time-consuming pretreatment and statistical counting, rather than providing direct concentration data, complicating cross-study comparisons. To rapidly investigate microplastic pollution in environmental samples, machine learning (ML) algorithms combined with spectrometers have been employed to estimate microplastic concentrations without the need for extraction. While previous research has primarily focused on microplastic-spiked soils, this study explores the use of river and loess sediments spiked with four commonly used plastic polymers: polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC) at concentrations ranging from 0.1 wt

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Supplementary text and illustrations.

The growing need for the multiband photodetection of a single scene has promoted the development of both multispectral coupling and broadband detection technologies. Photodetectors operating across the infrared (IR) to terahertz (THz) regions have many applications such as in optical communications, sensing imaging, material identification, and biomedical detection. In this review, we present a comprehensive overview of the latest advances in broadband photodetectors operating in the infrared to terahertz range, highlighting their classification, operating principles, and performance characteristics. We discuss the challenges faced in achieving broadband detection and summarize various strategies employed to extend the spectral response of photodetectors. Lastly, we conclude by outlining future research directions in the field of broadband photodetection, including the utilization of novel materials, artificial microstructure, and integration schemes to overcome current limitations. These innovative methodologies have the potential to achieve high-performance, ultra-broadband photodetectors.

The adaptation of Tibetans to high-altitude environments has been studied extensively. However, the direct assessment of evolutionary adaptation, i.e., the reproductive fitness of Tibetans and its genetic basis, remains elusive. Here, we conduct systematic phenotyping and genome-wide association analysis of 2,252 mother-newborn pairs of indigenous Tibetans, covering 12 reproductive traits and 76 maternal physiological traits. Compared with the lowland immigrants living at high altitudes, indigenous Tibetans show better reproductive outcomes, reflected by their lower abortion rate, higher birth weight, and better fetal development. The results of genome-wide association analyses indicate a polygenic adaptation of reproduction in Tibetans, attributed to the genomic backgrounds of both the mothers and the newborns. Furthermore, the EPAS1-edited mice display higher reproductive fitness under chronic hypoxia, mirroring the situation in Tibetans. Collectively, these results shed new light on the phenotypic pattern and the genetic mechanism of human reproductive fitness in extreme environments.

Abstract 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.

Kuahuqiao site, famous for its early rice cultivation, is taken to be a typical case of how agriculture emerged in a littoral environment in the early Holocene. However, the lack of fire history and local climatic reconstruction has hindered the detailed picture of agricultural origins and development. Here we report new records of TOC, BC, δ13CTOC, δ13CBC, and C/N, alongside published pollen and charcoal data. Our δ13CTOC and C/N confirm the previously-proposed formation of wetlands, which offered favorable landscapes for rice paddy agriculture, prior to the appearance of the Kuahuqiao culture. Based on BC, δ13CTOC, and δ13CBC records we suggest a hotter but drier climate that would have benefited rice agriculture by augmenting the distribution of wild rice and C4 herbs. In addition, δ13CTOC shows a decreased C3/C4 ratio as a signal of human occupation with manipulation of forest for hunting-gathering or/and land clearance for agriculture. Combined δ13CBC and BC records oppose the proposal of intense fire use in early agriculture and suggest that fire use was constrained to domestic purposes. Flood events which seem to have terminated the Kuahuqiao culture left impressions in TOC, BC, δ13CTOC, δ13CBC.

全新世以来,全球增温、人类活动加剧,使得火演化规律和火机制愈加复杂.系统性地研究全新世火活动的时空演化规律,不仅可以更清晰地理解区域火活动机制与气候因子、植物特征以及人类活动之间的关联,而且对预测未来火的演化趋势具有现实的指导意义.文章综合对比分析了中国中东部季风区域全新世以来的炭屑/黑碳沉积记录,发现该区域全新世火活动呈现出较大的时空差异.空间分布上,该区域火活动最活跃期从东北至东南呈现随纬度降低而趋晚的趋势,即东北地区早、中全新世,黄土高原和长江流域的中全新世(分别约为8.0～6.0 ka B.P.、6.0～4.5ka B.P.),以及南部地区晚全新世(4.0-2.0 ka B.P.)火活动较强;时间序列上,该区域火活动在4.0 ka B.P.前后呈现明显不同的变化规律,其中中国南部地区、黄土高原及东北地区自约4.0 ka B.P.后火活动有明显增强;长江流域该时段前后火活动有所减弱,直至约2.2 ka B.P.前后火活动有所回升.综合分析认为,在中早全新世,不同地区火活动最活跃期主要受控于水热配置影响,但生物量和局域人类活动因素不可忽略;在晚全新世约4.0 ka B.P.前后长江流域火活动因先民伐林活动导致植被覆盖下降而有所抑制,而其他地区约4.0 ka B.P.以来的人类活动对于当地火事件具有增强的影响.此外,通过综合不同沉积环境的炭屑/黑碳记录来反演火历史规律,需要考虑燃料来源、搬运沉积过程以及研究方法差异性的影响.不仅如此,有效区分人为火活动和自然火活动是预测未来增温背景下火活动变化和控制因素的一个亟需解决的科学难题.

The strength of the East Asian Summer Monsoon (EASM) and associated moisture availability have been linked to the spatial distribution of occurrence of C3 and C4 vegetation on the Chinese Loess Plateau (CLP). Variations in the stable carbon isotopic composition of organic matter in loess-paleosol sequences from several locations on the CLP indicate that vegetation has shifted from mainly C3 plants during cool, dry glacials to more C4 plants during warm, wet interglacials. Although increased temperatures generally lead to an expansion of C4 vegetation, increased humidity has an opposite effect, as does increasing pCO2, leaving the exact driver(s) of vegetation change, and thus EASM strength, elusive. Here we reconstruct continuous, directly comparable records of air temperature, monsoon precipitation, and vegetation type over the past 200,000 years based on branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids, plant leaf waxes and their isotopic stable carbon and hydrogen isotopic composition (d13Cwaxand d2Hwax, respectively) preserved at Lingtai on the central CLP. BrGDGT-based temperatures vary between 12 and 21 ??C over glacial-interglacial cycles, and consistently lead changes in loess proxies (grain size, magnetic susceptibility), as also observed elsewhere on the CLP. Variations in d13Cwax are only minor (<2%o) and indicate that C3 plants have continuously dominated at Lingtai, in contrast to a nearby section where C4 plants flourished during interglacials. This difference can be explained by the site elevation (-1300 m above sea level), resulting in air temperatures too low for widespread C4 vegetation occurrence. Instead, variations in the average chain length of the leaf waxes coinciding with large shifts in d2Hwax (-40%o) during glacial-interglacial transitions suggest that changes in rainfall source and seasonality may have pushed C3 woody vegetation present during glacials to more non-woody C3 vegetation during interglacials, as a result of differences in respective water-use efficiency. Our multiproxy records thus indicate that subtle changes in the C3 species composition can be used to reveal variations in EASM precipitation dynamics in elevated areas where temperature exerts a first order control on the vegetation type. ?? 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

In order to improve the knowledge of the microplastic pollution in the sparsely populated area, a preliminary monitoring survey was carried out in the northwest of China. Microplastics were evaluated in 28 soils collected from 6 sites by the methods of density separation and identified by microscope and Flourier infrared spectrum instrument. Microplastics were detected in all sampling points but the abundances, morphologies and polymers varied in different sampling points due to the natural conditions and anthropogenic influences. And the size of the detected microplastics is larger in comparison with other study areas. But with time, the degraded microplastics still could threat the ecology and environment. This study is helpful to get the whole pictures of microplastics around the world.

The inner shelf mud wedge (ISMW) located in the East China Sea (ECS) is the fine-grained sedimentary area with high sedimentation rate and has provided an ideal study area for understanding the East Asian Summer Monsoon (EASM) evolution during the Holocene. In this paper, we presented the high-resolution geochemical data of the sediments from the core MD06-3040 in the ISMW of the ECS determined by X-ray fluorescence core scanning (XRF-CS) analysis, a high-resolution, continuous, and multi-element method. Geochemical and factor analysis results reveal that the variations of elemental compositions (Al, Si, K, Ti, Fe), the elemental ratios of Al/Zr, Ca/Ti and Rb/Sr, and the factor scores (F1) are correlated with the changes of the EASM during the period of 6000–1300 cal yrBP. The higher values of geochemical compositions indicating the terrigenous inputs implied the intensification of anthropogenic activities after 1300 cal yrBP. Meanwhile, the significant decrease of most geochemical compositions and the F1 factor scores during 4500–3500 cal yrBP and 1700–1500 cal yrBP, within the dating errors, coincided with the weak EASM events (presumably drought and cold events). The spectral analysis results of K concentrations, Al/Zr ratios and F1 factor scores show the millennial and centennial climatic fluctuations, which are consistent with other marine sedimentary records in the adjacent areas. All the findings show that the geochemical compositions of sediments from core MD06-3040 are influenced by the EASM evolution, the variable El Niño/Southern Oscillation (ENSO) and the local oceanic thermohaline circulation (e.g., Kuroshio Current). These results are greatly helpful in uncovering the forcing mechanism of the monsoonal climate in the east China over the Holocene and also contribute to the understanding of EASM variability.

The East Asian summer monsoon (EASM) system plays a crucial role in regulating climatic and hydrological variability in East Asia. The hydrological effects of the EASM in eastern China during the Little Ice Age (LIA) remains controversial, however. Here, we established a relatively high-resolution palaeohydrological record over the last 700 years in East China via analyzing n-alkanes from a peat core. Mid- and long-chain (C-21-C-25 and C-27-C-31) n-alkanes account for more than 95% of the total odd-carbon-numbered n-alkanes, with short-chain n-alkanes (C-17-C-19) accounting for only 2.3% on average, suggesting that organic matter in the peat core originated primarily from vascular plants. Organic geochemical indices, including P-aq (an indicator of contributions from aquatic plants), the average chain length (ACL) of long-chain n-alkanes, and C-31/C-27 and C-23/C-29 n-alkane ratios, suggest a transition from dry conditions during the middle LIA to wet conditions in the late LIA. Comparing P-aq records from the study profile with previous records from the EASM region, we found that the northern and southern parts of eastern China showed contrasting changes in humidity during the LIA. Specifically, the southern part shifted from mid-LIA dry conditions to late-LIA wet conditions, whereas the northern part shifted from mid-LIA wet conditions to late-LIA dry conditions. This spatial heterogeneity in hydroclimate could be attributed to La Nina-like conditions and intense summer monsoons during the middle LIA and El Nino-like conditions and weak summer monsoons during the late LIA. Our study demonstrates the importance of understanding spatial heterogeneity of hydroclimatic changes to probe the mechanisms whereby EASM modulates regional climatic changes during the LIA.

Global warming and human activity are thought to be the primary drivers of the globally rising occurrences of forest fires. Due to the importance of local to regional environmental drivers in mediating fire frequencies, reconstructing fire histories of representative geographic regions is important to understand fire regimes and predict future changes. The present study aims to establish a relatively high-resolution fire record of boreal forests in northeastern (NE) China and identify the primary environmental drivers. We analyzed the concentration and stable carbon isotopic composition of black carbon (BC and delta C-13(BC)) of a 34,000 cal yr BP sedimentary sequence from a crater lake (Tianchi). The results show that fire events and C-4 plants were scarce during the late Last Glacial but increased since the deglaciation. Both fire and the abundance of combusted C-4 plants reached their maxima during the early Holocene, which may be attributed to rising temperatures due to intensified solar radiation and summer monsoons. During mid-to-late Holocene, fire events remained relatively stable and were primary associated with C-3 plants burning. Fire was particularly infrequent and C-3 trees were abundant during the periods of 5500-3100 cal yr BP and 1500-150 cal yr BP, which can be attributed to a wet climate. Fires exhibited evident increases from 150 cal yr BP to the present, suggesting a substantial role of human activities. Both BC and delta C-13(BC) during the Holocene show a significant correlation with pollen-based temperatures but not with precipitation, suggesting that temperature rises played a primary role in stimulating forest fires via mediating effective moisture. Collectively, these findings suggest that forest fires and C-4 plants would likely increase in NE China in response to global warming and increasingly intensive anthropogenic disturbance, highlighting the importance of establishing a long-term understanding of fire regimes to create more sustainable, science-based fire management strategies.

The reconstruction of past climates and vegetation can provide valuable information for understanding the mechanisms of the variability of the East Asian summer monsoon in eastern China. In this study, organic geochemical evidence from the compositions of sedimentary leaf-wax stable isotopes and n-alkane parameters investigates the changes in vegetation and climate over the last 1200 years in the Xiyaohu peatland, Jiangxi Province, southeast China. Combined with temperature records, three climatic periods are presented: (a) a warm and humid period with an increase in C4 plants from 900 to 1450 AD, which coincides with the Medieval Warm Period (MWP); (b) a cool and dry period with the expansion of C3 plants from 1450 to 1800 AD, coinciding with the Little Ice Age (LIA); and (c) the Present Warm Period (PWP) from 1800 AD until the present, with warm and wet conditions. The sub-stages within the MWP and LIA intervals are also presented. The earlier MWP stage (900–1125 AD) was drier than the latter one (1125–1450 AD), and the earlier LIA stage (1450–1650 AD) was drier than the late LIA (1650–1800 AD). Increased solar irradiance and enhanced El Niño activities are related to the warm and humid climate during the MWP and PWP, whereas reduced solar irradiance and La Niña activities correspond to the cool and dry climate during the LIA. The present results provide insights into paleoclimatic changes in eastern monsoonal China and provide an understanding of centennial-scale climatic fluctuations and their driving factors.

The inner shelf sediments of the East China Sea (ECS) preserve valuable information regarding climatic changes on land through detrital material discharged from large rivers, particularly the Yangtze River. In this paper, we examine the provenance changes of fine-grained detrital quartz preserved in the sediment of the MD06-3040 core retrieved from the mud belt on the inner shelf of the ECS during the last 6 kyrs. The provenance of the fine silt fraction (4–16 μm) of the sediments, which is considered to represent the suspended particulate matter (SPM) from the Yangtze River, is estimated based on the electron spin resonance (ESR) signal intensity and crystallinity index (CI) of quartz. By comparing the ESR signal intensity and CI of quartz in the fine silt fraction of sediments to those from different parts of tributaries in the modern Yangtze River drainage, we can discriminate the SPM sourced from the northwestern and southeastern tributaries of the Yangtze River. Shifts in the East Asian summer monsoon (EASM) front are monitored by changes in the main precipitation areas which are manifested as changes in source rock ages and types implied from the ESR signal intensity and CI of quartz in the fine silt fraction of the studied sediments discharged from the Yangtze River. Temporal changes in provenance of the fine silt fraction through time suggest that shifts in the main location of EASM precipitation (most likely representing the EASM front) occurred at a multi-centennial-to-millennial scale with the deepest northwestward penetration of the EASM precipitation front (an enhanced EASM) occurring during the period 3.5–2.0 kyr BP and a southeastward retreat (a weak EASM) occurring during the periods 6.0–4.1 and 2.0–0 kyr BP.

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It remains debatable whether slash-and-burn practices were adopted in rice cultivation by the Neolithic Kuahuqiao culture in the Ningshao Plain, one of the birthplaces of rice farming. Here, we established charcoal-based indices to reconstruct the history of fire and vegetation in the Ningshao Plain since the last glacial period. We collected representative modern vegetation and conducted combustion and fragmentation experiments to simulate fire and depositional processes, respectively. Charcoals from modern vegetation show clear morphological differences between herbaceous and woody plants. In particular, the length to width ratios (L/W) of herbaceous charcoals were systematically higher than those of woody charcoals, and the associated end-member values were 4.50 and 1.94, respectively. These values were then applied to sediment cores (KHQ-14/15) collected in proximity to the Kuahuqiao archaeological site. Results show that the amount of combusted herbaceous plants increased sharply after the Holocene, and the most remarkable rise occurred around 8550 yr B.P. This observation may reflect local environment (sedimentary and/or climatic) changes or small-scale early human activities. During the Kuahuqiao cultural period (8250-7450 yr B.P.), the relative abundance of woody charcoals increased, but the overall fire intensity decreased. This finding suggests that the Kuahuqiao farming was restricted to a small geographic area and large-scale slash-and-burn farming activities were not adopted.