Tibetan Plateau

青藏高原
  • 文章类型: Journal Article
    羰基化合物在对流层中普遍存在,在大气氧化能力(AOC)中起着至关重要的作用。特别是在光化学活跃的地区,如青藏高原(TP)。然而,由于缺乏全面的观察和建模,人们对TP上羰基的组成和演化仍然知之甚少。这里,2022年夏季,我们在拉萨郊区进行了37种羰基化合物及其前体的密集现场测量。在臭氧污染事件中发现了更高水平的羰基化合物(7.24±3.83ppbv),比非发作期高出36%。甲醛是最丰富的羰基(38%),主要来自光化学次级地层。使用大气化学快速自适应优化模型(ROMAC)进行的模拟表明,拉萨的AOC很强,·OH和·HO2的白天最大值分别为9.8×106和4.2×108分子cm-3,甚至高于中国大多数特大城市的水平。值得注意的是,在发作期间,随着羰基化合物的增加,AOC显着增强,·OH和·HO2的浓度比非发作期分别增加了21%和67%,分别。预算分析表明,·HO2NO(88%)和·OHVOC(74%)途径主导了·OH的产生和损失,分别。对于·HO2,它们是·RO2NO(67%)和·HO2NO(83%)。这项研究为生态脆弱和气候敏感的TP地区强大的AOC提供了宝贵的见解,并强调了人为-生物相互作用在TP活性光化学中的关键作用。
    Carbonyls are ubiquitous in the troposphere and play a crucial role in atmospheric oxidation capacity (AOC), particularly in photochemistry-active regions such as the Tibetan Plateau (TP). However, the composition and evolution of carbonyls over the TP is still poorly understood due to a lack of comprehensive observations and modelling. Here, we conducted an intensive field measurement of 37 carbonyls and their precursors at a suburban site in Lhasa during summer 2022. Markedly higher levels of carbonyls (7.24 ± 3.83 ppbv) were found during ozone pollution episodes, with 36 % higher than those during non-episodes. Formaldehyde was the most abundant carbonyl (38 %), which primarily originating from photochemical secondary formations. Simulations using the Rapid adaptive Optimization Model for Atmospheric Chemistry (ROMAC) indicated strong AOC in Lhasa, with the daytime maximum of ·OH and ·HO2 of 9.8 × 106 and 4.2 × 108 molecules cm-3, respectively, which were even higher than that in most of the megacities in China. Notably, AOC significantly enhanced with the increasing carbonyls during the episodes, with the concentrations of ·OH and ·HO2 were boosted 21 % and 67 % than those during non-episodes, respectively. Budget analysis revealed that the ·HO2 + NO (88 %) and ·OH + VOC (74 %) pathways dominated the generation and loss of ·OH, respectively. And for ·HO2, they were ·RO2 + NO (67 %) and ·HO2 + NO (83 %). This study provides valuable insights into the strong AOC in the ecologically-fragile and climate-sensitive TP region, and highlighted the crucial role of anthropogenic-biogenic interactions in the active photochemistry of TP.
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  • 文章类型: Journal Article
    水生生态系统中存在的重金属对环境和人类健康构成重大威胁。在这项研究中,我们分析了各种重金属(As,Cr,Co,Ni,Cu,Mo,Cd,Pb和Sb)使用2021年和2023年从青藏高原收集的大量地表水样品。结果表明,与冰川盆地相比,下游水样的重金属含量更高(平均12.6μg/L)。值得注意的是,冰川盆地和下游的重金属含量差异显着(4.6-29.1μg/L和7.8-55.2μg/L,分别)。然而,某些地点的浓度升高(例如,佐贺县和当克藏布河)主要归因于单个重金属的不成比例的贡献,可能源于特定的人类活动或自然条件。在冰川盆地,随着Sc浓度的增加,只有Cr的富集因子(EF)呈下降趋势,然而,在下游地区,大多数元素呈现下降趋势。此外,除了几个采样点,冰川盆地的重金属浓度保持相对平衡,这表明这些金属主要来自天然来源。单个元素(Eri)和潜在生态风险指数(PER)的潜在生态风险值表明,与水生生态系统中几乎重金属(As除外)相关的生态和人类风险最小。环境意义:水生生态系统中的重金属对生态和人类健康构成重大威胁。由于青藏高原微妙的生态平衡及其作为水资源的关键作用,我们分析了各种重金属(As,Cr,Co,Ni,Cu,Mo,Cd,陆地地表水中的Pb和Sb)浓度和EF,了解水生生态系统中重金属的污染水平和可能来源。风险评估结果表明,青藏高原地区砷的防治工作需要重视,但是大多数重金属对生态和人类健康没有威胁。
    Heavy metals present in aquatic ecosystems constitute a significant threat to both the environment and human health. In this study, we analyzed various heavy metals (As, Cr, Co, Ni, Cu, Mo, Cd, Pb and Sb) using extensive surface water samples collected from the Tibetan Plateau in 2021 and 2023. Results showed that downstream water samples exhibited higher content (mean 12.6 μg/L) of heavy metals compared to those from the glacier basins. It is noteworthy that heavy metal content varied significantly both in the glacier basin and downstream (4.6-29.1 μg/L and 7.8-55.2 μg/L, respectively). However, elevated concentrations at certain sites (e.g., Saga County and Dangque Zangbu River) were primarily attributed to the disproportionate contribution of individual heavy metals, possibly stemming from specific human activities or natural conditions. In the glacier basin, only Cr exhibited a decreasing trend in enrich factors (EF) with increasing Sc concentration, whereas, in the downstream areas, most elements displayed a declining trend. Furthermore, apart from a few sampling sites, heavy metal concentrations in the glacier basin remained relatively balanced, suggesting that these metals predominantly originate from natural sources. The values of potential ecological risk for an individual element (Eri) and potential ecological risk index (PER) indicate that the ecological and human risks associated with almost heavy metals (except As) in the aquatic ecosystem are minimal. ENVIRONMENTAL IMPLICATION: Heavy metals in aquatic ecosystems pose a significant threat to ecological and human health. Due to delicate ecological balance of the Tibetan Plateau and its critical role as a water resource, we analyzed various heavy metals (As, Cr, Co, Ni, Cu, Mo, Cd, Pb and Sb) concentrations and EF in land surface river water, to find out the pollution levels and possible sources of heavy metals in the aquatic ecosystems. The results of risk assessment showed that the prevention and management of arsenic in Tibetan Plateau needs attention, but most heavy metals pose no threaten to ecological and human health.
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  • 文章类型: Journal Article
    生物质燃烧通过改变大气成分在全球碳循环中起着关键作用,并影响区域和全球气候。尽管它很重要,世界上很少有高分辨率的记录,尤其是最近的气候变化。本研究分析了左旋葡聚糖,生物质燃烧排放物的特定示踪剂,在从舒勒河冰川编号中检索到的38年冰芯中。4、青藏高原东北部。舒乐河冰川No.4个冰芯的范围为0.1至55ngmL-1,平均浓度为8±8ngmL-1。浓度从2002年到2018年呈下降趋势。同时,同期,中亚地区野火活动也呈下降趋势,表明舒勒河冰川编号的左旋葡聚糖浓度之间的潜在对应关系。4.中亚的冰芯和火活动。此外,舒乐河冰川号的左旋葡聚糖浓度之间也存在正相关。从2002年到2018年,中亚有4个冰芯和野火。虽然向后的空气质量轨迹分析和火点数据显示,与中亚相比,南亚的火灾数量分布更高,但全年北半球西风环流占主导地位。因此,舒勒河冰川中的左旋葡萄糖山图4提供了中亚野火通过西风对青藏高原冰川影响的明确证据。这凸显了冰芯数据对青藏高原冰川地区野火历史重建的重要性。
    Biomass burning play a key role in the global carbon cycle by altering the atmospheric composition, and affect regional and global climate. Despite its importance, a very few high-resolution records are available worldwide, especially for recent climate change. This study analyzes levoglucosan, a specific tracer of biomass burning emissions, in a 38-year ice core retrieved from the Shulehe Glacier No. 4, northeastern Tibetan Plateau. The levoglucosan concentration in the Shulehe Glacier No. 4 ice core ranged from 0.1 to 55 ng mL-1, with an average concentration of 8 ± 8 ng mL-1. The concentrations showed a decreasing trend from 2002 to 2018. Meanwhile, regional wildfire activities in Central Asian also exhibited a declining trend during the same period, suggesting the potential correspondence between levoglucosan concentration of the Shulehe Glacier No. 4 ice core and the fire activity of Central Asia. Furthermore, a positive correlation also exists between the levoglucosan concentration of the Shulehe Glacier No. 4 ice core and the wildfire counts in Central Asia from 2002 to 2018. While backward air mass trajectory analysis and fire spots data showed a higher distribution of fire counts in South Asia compared to Central Asia, but the dominance of westerly circulation in the northern TP throughout the year. Therefore, the levoglucosan in the Shulehe Glacier No. 4 provides clear evidence of Central Asian wildfire influence on Tibetan Plateau glaciers through westerlies. This highlights a great importance of ice core data for wildfire history reconstruction in the Tibetan Plateau Glacier regions.
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  • 文章类型: Journal Article
    在气候变暖和增湿的背景下,高精度的降雨侵蚀力制图对于准确评估青藏高原(TP)区域土壤侵蚀至关重要。尽管高时空分辨率的网格化降水数据为降雨侵蚀率制图提供了基础,当直接从网格化降水数据中计算降雨侵蚀度时,降雨的空间异质性随着时间粒度的降低而增加,会导致更大的误差。在这项研究中,建立了站点尺度转换系数,以便使用每小时数据计算的降雨侵蚀力可以转换为使用每分钟数据计算的降雨侵蚀力。建立了基于第三极网格化降水数据集(TPHiPr)的高分辨率小时降水数据的修正模型,用于计算降雨侵蚀力。结果表明,使用TPHiPr获得的原始计算结果存在明显的低估,但两组结果之间有很强的相关性。模型修正后,纳什-萨克利夫效率系数(从-0.39到0.80)和百分比偏差(从-63.95%到0.37%)有了显着改善。TPHiPr有效地描述了TP上降雨侵蚀力的空间特征。它准确地反映了喜马拉雅山北翼和横断山脉干热山谷的雨影区域。在喜马拉雅山东部南部的热带雨林地区,它还显示出很高的降雨侵蚀力值。在1981年至2020年期间,TP的降雨侵蚀力总体趋势有所增加,其中65.91%的地区呈增加趋势,22.25%的地区呈显着增加趋势,表明水蚀的风险加剧。这些发现表明,40年高空间分辨率的降雨侵蚀力数据集可以为定量了解TP上的土壤侵蚀提供准确的数据支持。
    High-precision rainfall erosivity mapping is crucial for accurately evaluating regional soil erosion on the Tibetan Plateau (TP) under the backdrop of climate warming and humidification. Although high spatiotemporal resolution gridded precipitation data provides the foundation for rainfall erosivity mapping, the increasing spatial heterogeneity of rainfall with decreasing temporal granularity can lead to greater errors when directly computing rainfall erosivity from gridded precipitation data. In this study, a site-scale conversion coefficient was established so that rainfall erosivity calculated using hourly data can be converted to rainfall erosivity calculated using per-minute data. A revised model was established for calculating the rainfall erosivity based on high-resolution hourly precipitation data from the Third Pole gridded precipitation dataset (TPHiPr). The results revealed a notable underestimation in the original calculation results obtained using the TPHiPr, but strong correlation was observed between the two sets of results. There was a significant improvement in the Nash-Sutcliffe coefficient of efficiency (from -0.39 to 0.80) and the Percent Bias (from -63.95 % to 0.37 %) after model revision. The TPHiPr effectively depict the spatial characteristics of rainfall erosivity on the TP. It accurately reflected the rain shadow area on the northern flank of the Himalayas and the dry-hot valley in the Hengduan Mountains. It also showed high rainfall erosivity values in the tropical rainforest area on the southern flank of the eastern Himalayas. The overall trend of rainfall erosivity has increased on the TP during the period 1981 to 2020, with 65.91 % of the regions exhibiting an increasing trend and 22.25 % showing significant increases, indicating an intensified risk of water erosion. These findings suggest that the 40-year-high spatial resolution rainfall erosivity dataset can provide accurate data support for a quantitative understanding of soil erosion on the TP.
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  • 文章类型: Journal Article
    喜马拉雅-西藏造山带(HTO)的新生代地形发展极大地影响了高亚洲的古环境和生物多样性模式。然而,关于HTO的演化和古环境历史的概念在时间上大不相同,造山带不同元素的海拔增加和表面隆起顺序。使用大量转录组来源的标记的目标富集,祖先范围估计和古气候生态位建模,我们评估了最近提出的关于Paini部落的亚洲多刺青蛙的温带古西藏的概念,并重建了其历史生物地理。这个概念以前是在无脊椎动物中发展起来的。由于它们早期的进化起源,低分散能力,地方地方性很高,严格依赖于温度和湿度,多刺青蛙的枝条发生可能与HTO古环境的演变相呼应。我们表明,主要谱系的多样化发生在早期到中期,而高山类群的进化始于上新世晚期/上新世早期。我们的分布和生态位建模结果表明,范围变化和生态位稳定性可以解释多刺青蛙的现代分离分布。他们可能保持了他们的(亚)热带或(温暖)温带偏好,并随着气候变化从祖先的古藏族地区迁入喜马拉雅,而不是在原地适应。根据祖先范围估计,我们假设低海拔的存在,苗新世时期沿昆仑穿越古西藏的气候适宜走廊,羌塘和/或冈底山。我们的结果有助于更深入地了解HTO动物进化的机制和过程。
    The Cenozoic topographic development of the Himalaya-Tibet orogen (HTO) substantially affected the paleoenvironment and biodiversity patterns of High Asia. However, concepts on the evolution and paleoenvironmental history of the HTO differ massively in timing, elevational increase and sequence of surface uplift of the different elements of the orogen. Using target enrichment of a large set of transcriptome-derived markers, ancestral range estimation and paleoclimatic niche modelling, we assess a recently proposed concept of a warm temperate paleo-Tibet in Asian spiny frogs of the tribe Paini and reconstruct their historical biogeography. That concept was previously developed in invertebrates. Because of their early evolutionary origin, low dispersal capacity, high degree of local endemism, and strict dependence on temperature and humidity, the cladogenesis of spiny frogs may echo the evolution of the HTO paleoenvironment. We show that diversification of main lineages occurred during the early to Mid-Miocene, while the evolution of alpine taxa started during the late Miocene/early Pliocene. Our distribution and niche modelling results indicate range shifts and niche stability that may explain the modern disjunct distributions of spiny frogs. They probably maintained their (sub)tropical or (warm)temperate preferences and moved out of the ancestral paleo-Tibetan area into the Himalaya as the climate shifted, as opposed to adapting in situ. Based on ancestral range estimation, we assume the existence of low-elevation, climatically suitable corridors across paleo-Tibet during the Miocene along the Kunlun, Qiangtang and/or Gangdese Shan. Our results contribute to a deeper understanding of the mechanisms and processes of faunal evolution in the HTO.
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  • 文章类型: Journal Article
    作为古代海洋岩石圈的遗迹,蛇绿岩是标记缝合线的最重要的岩石学证据,并且在重建钢板配置中也起着关键作用。它们还为研究现代洋脊上发生的地壳增生和地幔过程提供了宝贵的窗口。大量的蛇绿岩沿着雅鲁藏布缝合线分布,代表了新特提斯海洋岩石圈的遗迹。它们的特征是不完整的岩石地层学,其中地幔部分比地壳部分厚得多。Yarlung-Tsangpo蛇绿岩中出现的海洋地壳岩石比正常的海洋地壳(〜7km)薄得多,甚至没有。雅鲁藏布蛇绿岩起源的构造环境仍然存在很大争议,尽管上俯冲带的起源盛行。此外,它们不完整的岩性地层通常归因于它们形成后后期的构造分裂。然而,这种不完整性类似于在现代超缓慢扩张的山脊上产生的海洋岩石圈,例如西南印度岭(SWIR)。在本文中,我们提供了几行证据,支持在超缓慢扩张的山脊上形成Yarlung-Tsangpo蛇绿岩,在此期间形成了分离断层。这表明Yarlung-Tsangpo蛇绿岩可能代表了新特提斯海洋中的海洋核心复合物(OCC)。海底高地形的OCC在海沟中被堵塞,并通过印度-欧亚大陆碰撞保存为蛇绿岩。堵塞导致旧俯冲的消亡,并在堵塞的OCC下方重新开始了新的俯冲。
    As relics of ancient ocean lithosphere, ophiolites are the most important petrological evidence for marking the sutures and also play a key role in reconstructing plate configuration. They also provide valuable windows for studying crustal accretion and mantle processes occurring at modern ocean ridges. Abundant ophiolites are distributed along the Yarlung-Tsangpo suture and represent the relics of ocean lithosphere of the Neo-Tethys. They are characterized by an incomplete litho-stratigraphy, of which the mantle section is much thicker than the crustal section. Ocean crustal rocks outcropped in the Yarlung-Tsangpo ophiolites are much thinner than normal ocean crusts (~ 7 km) or even absent. Tectonic settings from which the Yarlung-Tsangpo ophiolites originated remain highly controversial, although an origin of the supra-subduction zone is prevailing. Moreover, their incomplete litho-stratigraphy has been commonly attributed to tectonic dismemberment during the late-stage emplacement after their formation. Nevertheless, such an incompleteness resembles the ocean lithosphere generated at modern ultraslow spreading ridges, such as the Southwest Indian Ridge (SWIR). In this paper, we present several lines of evidence that support the formation of the Yarlung-Tsangpo ophiolites at ultraslow spreading ridges, during which detachment faults were developed. This suggests that the Yarlung-Tsangpo ophiolites might represent the ocean core complexes (OCC) in the Neo-Tethys Ocean. The OCC with high topography in the seafloor were clogged in the trench and preserved as ophiolites through Indo-Eurasia collision. The clogging resulted in the demise of an old subduction and a new subduction was re-initiated beneath the clogged OCC.
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  • 文章类型: Journal Article
    球藻是亚洲和美洲重要的捕食性甲虫。目前,很少有研究对中国特别是青藏高原的C.transversoguttata进行调查。在这项研究中,对从西藏收集的8个C.transversoguttata种群进行了全长16srRNA测序和qPCR实验,以分析其细菌群落和细菌丰度。总之,我们的结果揭示了微生物的组成,青藏高原C.transversoguttata种群细菌群落的多样性和细菌滴度。在未来,有必要探索从不同地点收集的各种跨花椰菜种群之间的微生物群差异。这些结果增加了我们对C.transversoguttata的复杂细菌群落及其作为潜在生物防治因子的利用的理解。
    Coccinella transversoguttata is an important predatory beetle in Asia and America. Currently, few studies have investigated C. transversoguttata in China especially in the Tibetan plateau. In this study, full-length 16 s rRNA sequencing and qPCR experiment were performed on eight C. transversoguttata populations collected from Tibet to analyze their bacterial communities and bacteria abundance. In summary, our results revealed the microbial compositions, diversities and bacterial titers in the bacterial communities in C. transversoguttata populations in the Tibetan plateau. In future, there is a need to explore the differences in microbiota among various C. transversoguttata populations collected from different locations. These results add to our understanding of the complex bacterial communities of C. transversoguttata and their utilization as potential biocontrol factors.
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  • 文章类型: Journal Article
    尽管机器人手术系统在胸外科的发展中积累了丰富的经验,其在西藏地区的应用相对较晚。我们报告了有关达芬奇系统在胸外科手术中的经验,并观察了其实用性和手术效果。
    我们回顾性分析了26例接受机器人胸外科手术的患者,包括:12例肺切除术,两次食管切除术,十次纵隔手术和两次肋骨肿块切除术。患者特征的数据,手术时间,收集围手术期并发症。
    在26名患者中,达芬奇系统成功完成22例,包括7个部分切除术,4个肺活瘤,1次节段切除术,2例食管切除术,10例纵隔手术(6例胸腺切除术,3后纵隔肿瘤切除术,纵隔囊肿切除1例)和肋骨肿块切除2例。其中,3例采用机器人技术开始的肺切除术转换为胸腔镜手术(由于肺门淋巴结钙化),1例双叶切除术因胸部粘连转为开胸手术。所有手术都进行得很顺利,没有病人需要输血。所有患者术后恢复满意。
    它是安全的,在高原上开展机器人胸外科手术的可靠性和有效性。在认真认真讨论手术适应证的前提下,积极开展达芬奇机器人手术系统在西藏高原的应用。
    UNASSIGNED: Although the robotic surgical system has accumulated rich experience in the development of thoracic surgery, its application in Tibet area is relatively late. We report our experience concerning da Vinci Xi system in thoracic surgery and observe its practicability and surgical effect.
    UNASSIGNED: We retrospectively analyzed 26 patients who underwent robotic thoracic surgery including: twelve lung resection, two esophagectomies, ten mediastinal surgeries and two rib mass resection. The data of patient characteristics, operative time, perioperative complications were collected.
    UNASSIGNED: Of the 26 patients, 22 cases were completed with da Vinci system successfully, including 7 segmentectomies, 4 lobectomies, 1 subsegmentectomy, 2 esophagectomies, 10 mediastinal surgeries (6 thymic resections, 3 posterior mediastinal tumor resection, 1 mediastinal cyst resection) and 2 rib mass resection. In which, 3 cases of lung resection begun with robotic technique were converted to thoracoscopic surgery (due to calcification of hilar lymph node), 1 case of bilobectomy was converted to thoracotomy due to thoracic adhesion. All the operations went well and no patients need blood transfusion. All patients had satisfactory postoperative recovery.
    UNASSIGNED: It is safe, reliable and effective to carry out robotic thoracic surgery on the plateau. On the premise of carefully and seriously discussing the indications of surgery, we should actively carry out the application of da Vinci robotic surgery system in Tibet Plateau.
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  • 文章类型: Journal Article
    青藏高原(TP)由于其极端的居住环境,是人类长期定居最具挑战性的地区之一。了解这种极端环境中人类活动与环境变化的关系具有重要意义,可以为适应未来气候变化提供历史参考。在这项研究中,我们以TP南部的安格伦盆地为例,阐明了自小冰河时代(LIA)以来的关系。在粪便中使用粪便甾烷醇,湖泊和河流表面沉积物,表层土壤,和沉积物核心,我们发现,具体指标S1和S2的成分,表前列腺素,5β-乙基前列腺素和5β-乙基吡啶前列腺素可以反映人口和草食动物的变化,分别。通过比较由晶粒尺寸决定的环境变化,元素,沉降速率,和其他气候记录,解释了人类活动与环境变化之间的关系。我们的结果表明:(I)公元1480-1820年,湖泊沉积物中的粪便甾烷主要来自牲畜,人口很少。相比之下,在1820-2021年的CE,S1的比例和通量一直在不断增加,表明人口显著增长。(ii)在LIA中间,寒冷干燥的气候抑制了农业和农业的发展。然而,LIA后期降水的增加促进了这种发展,导致人口和牲畜在短期内增加。(三)1951年以来,人们开荒,发展畜牧业,导致土壤侵蚀增加。(四)过去40年,在温暖潮湿的气候和良好的政策支持下,人类活动,如农业和畜牧业,迅速增加,但是由于良好的水土保持努力,土壤侵蚀在最近20年有所下降。这项研究揭示了人类活动与环境变化之间的关系,并为未来的气候变化响应提供了见解。
    The Tibetan Plateau (TP) is one of the most challenging areas for human long-term settlement due to its extreme living environment. Understanding the relationship between human activities and environmental changes in this extreme environment is important and can provide a historical reference for adapting to future climate change. In this study, we took the Angren Basin in the southern TP as a case study to elucidate the relationship since Little Ice Age (LIA). Using fecal stanol in feces, lake and river surface sediments, surface soils, and sediment core, we found that specific indices S1 and S2 from the composition of coprostanol, epicoprostanol, 5β-ethylcoprostanol and 5β-ethylepicoprostanol can reflect changes in human population and herbivores, respectively. Through the comparison between environmental changes determined by grain size, elements, sedimentation rate, and other climate records, the relationship between human activities and environmental changes was interpreted. Our results indicate that: (i) during 1480-1820 CE, the fecal stanols in lake sediments mainly originated from livestock, and the human population was low. In contrast, during 1820-2021 CE, the proportion and flux of S1 have been continuously increasing, indicating significant population growth. (ii) During the middle LIA, the cold-dry climate inhibited the development of agriculture and farming. However, the increased precipitation during the late LIA promoted that development, resulting in an increase in human population and livestock in a short term. (iii) Since 1951, people have reclaimed wasteland and developed husbandry, leading to increased soil erosion. (iv) Over the past 40 years, with a warm-humid climate and good policy support, human activities, such as agriculture and husbandry, have rapidly increased, but soil erosion has declined in the recent 20 years due to good soil-water conservation efforts. This study sheds light on the relationship between human activities and environmental changes and provides insights into future climate change responses.
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  • 文章类型: Journal Article
    钠(Na),一种有益的矿物元素,通过渗透调节刺激植物生长。以前的研究集中在个体或物种水平的Na含量,然而,如果不探索特征(内容,密度,和储存)在社区一级的Na。我们在青藏高原(TP)的2040个自然植物群落中对不同植物器官进行了网格图采样,以在区域尺度上全面表征群落水平的Na。叶片中Na含量分别为0.57、0.09、0.07和0.71mgg-1,分支,树干,和根,分别。干旱胁迫下,沙漠中的生物群落Na含量较高。氧分压,辐射,降水,土壤Na供应,和温度显著影响Na含量的空间变化。此外,我们准确地模拟了Na密度的空间变化,并使用随机森林算法在TP上生成了高度精确的1km×1km植物Na密度空间图,这表明TP东南部的Na密度较高。植物在TP上的总Na储量估计为111.80×104t。这些发现为理解植物群落水平的适应策略和大规模评估矿质元素状况提供了很好的见解和参考。为今后的生态模型优化提供有价值的数据。
    Sodium (Na), a beneficial mineral element, stimulates plant growth through osmotic adjustment. Previous studies focused on Na content at the individual or species level, however, it is hard to link to ecosystem functions without exploring the characteristics (content, density, and storage) of Na at the community level. We conducted grid-plot sampling of different plant organs in 2040 natural plant communities on the Tibetan Plateau (TP) to comprehensively characterize community-level Na on a regional scale. The Na content was 0.57, 0.09, 0.07, and 0.71 mg g-1 in leaves, branches, trunks, and roots, respectively. Across biomes Na content was higher in deserts under drought stress. Oxygen partial pressure, radiation, precipitation, soil Na supply, and temperature significantly affected the spatial variation in Na content. Furthermore, we accurately simulated the spatial variation in Na density and produced a highly precise 1 km × 1 km spatial map of plant Na density on the TP using random forest algorithm, which demonstrated higher Na density in the southeast of TP. The total plant Na storage on the TP was estimated as 111.80 × 104 t. These findings provide great insights and references for understanding the plant community-level adaptation strategies and evaluating the mineral element status on a large scale, and provide valuable data for ecological model optimization in the future.
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