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Wetlands in the Qinghai–Tibet Plateau are a unique and fragile ecosystem undergoing rapid changes. We show two unique patterns of mercury (Hg) accumulation in wetland sediments. One is the 'surface peak' in monsoon-controlled regions and the other is the 'subsurface peak' in westerly-controlled regions. The former is attributed to the combined effects of increasing anthropogenic emissions and climate-induced changes in the cryosphere and wetland hydrology in the last 100−150 years. The climate changes in westerly-controlled regions in the last 50−70 years led to a fluctuation in hydrology and Hg peak in the sediment subsurface. The increase in legacy Hg input from soil erosion has largely enhanced the Hg accumulation rate in wetlands since the 1950s, especially in the proglacial wetlands. We highlight that accelerated glacier melting and permafrost thawing caused by global warming have altered geomorphology and hydrology, and affected Hg transport and accumulation in wetlands. [ABSTRACT FROM AUTHOR]

The fossil record evidences an old origin and diversification of Malvaceae in the Northern Hemisphere. The central Tibetan Plateau was at a low elevation with a monsoon influence during the Eocene, allowing the development of a subtropical flora containing Malvaceae. The taxonomic study of fossils from the Eocene of what is now the Tibetan Plateau is still ongoing. Malvaceae fossils from the Eocene Jianglang flora, are attributed to sub‐families Tilioideae and Sterculioideae, and are compared with modern species. A new specimen of Firmiana is described based on a fruit valve with a pinnate venation, the secondary veins starting at the ventral suture and reaching the midvein, and the seeds attached at the proximal part of the ventral suture. This specimen represents the earliest known occurrence of the genus. A new occurrence of Craigia is also reported based on detached membranous valves of a fruit capsule with a prominent fusiform locular area and radiating venation. Based on the fossil record of Firmiana and its modern distribution, we infer that the genus may have originated in East Asia and subsequently diversified in South China and Southeast Asia. The new occurrence of Craigia indicates that the genus was distributed in humid areas in South, Southwest and North China during the Eocene. Both fossil records evidence the important role that the Tibetan region played in the diversification of plants in East and Southeast Asia. [ABSTRACT FROM AUTHOR]

However the following combination of characters places the fossil in a separate entity within Cosmoscartini, as this tribe is currently understood: angulate border angulate border of frontoclypeus in dorsal view, anterior margin of pronotum protruded, posterior margin with distinct incision, long mesonotum (distinctly longer than half of the length of the pronotum in midline), more basal forking of ScP + R, long clavus, short tornus, and subtriangular shape of subgenital plates place the fossil separately within Cosmoscartini as this tribe is currently understood. MAP: Figure 7 Localities of fossil taxa ascribed to Cercopidae and the modern relatives (note that the taxonomic placement of the fossil record presented here is in need of revision). The family Cercopidae includes 178 genera and 1561 species [[7]], most closely related to the paraphyletic Aphrophoridae [[6]], which bear transverse compound eyes instead of the globose compound eyes of Cercopidae [[8]]. The oldest confirmed fossil known for the Cercopidae ( I Allocercopis punctatis i Lin, 1997) dates back to the Cretaceous-Paleocene [[11]] and two dubious cercopid fossils were recorded from the Cretaceous [[12]]. [Extracted from the article]

The often-used phrase 'the uplift of the Tibetan Plateau' implies a flat-surfaced Tibet rose as a coherent entity, and that uplift was driven entirely by the collision and northward movement of India. Here, we argue that these are misconceptions derived in large part from simplistic geodynamic and climate modeling, as well as proxy misinterpretation. The growth of Tibet was a complex process involving mostly Mesozoic collisions of several Gondwanan terranes with Asia, thickening the crust and generating complex relief before the arrival of India. In this review, Earth system modeling, paleoaltimetry proxies and fossil finds contribute to a new synthetic view of the topographic evolution of Tibet. A notable feature overlooked in previous models of plateau formation was the persistence through much of the Cenozoic of a wide east–west orientated deep central valley, and the formation of a plateau occurred only in the late Neogene through compression and internal sedimentation. [ABSTRACT FROM AUTHOR]

Cedrelospermum Saporta is an extinct genus in the Ulmaceae with abundant fossil records in North America and Europe. However, so far, fossil records of this genus from Asia are sparse, which limits the interpretations of the morphological evolution and biogeographical history of the genus. Here we report well‐preserved fruits (Cedrelospermum tibeticum sp. nov.) and a leaf (Cedrelospermum sp.) of Cedrelospermum from the upper Oligocene Lunpola and Nyima basins in the Qinghai–Tibetan Plateau (QTP). This is the first fossil record of Cedrelospermum in the QTP, showing that this genus grew in this region during the late Oligocene. Cedrelospermum tibeticum fruits are double‐winged, morphologically similar to the Eocene and Oligocene double‐winged Cedrelospermum species from North America. This supports the hypothesis that Cedrelospermum migrated to Asia from North America by way of the Bering Land Bridge. Given that Cedrelospermum was a typical element of Northern Hemispheric flora in the Paleogene and Neogene, the presence of this genus indicates that the central region of the QTP was phytogeographically linked with other parts of the Northern Hemisphere during the late Oligocene. The morphological observations of C. tibeticum fruits and other double‐winged Cedrelospermum fruits suggest an evolutionary trend from obtuse to acute apex for the primary wing. Cedrelospermum tibeticum likely had warm and wet climatic requirements. This type of an environment possibly existed in the central QTP in the late Oligocene, thereby supporting the survival of C. tibeticum. [ABSTRACT FROM AUTHOR]

Podocarpium is an extinct genus in Fabaceae with rich fossil records in Eurasia dating back to the Eocene. However, the diversification and biogeographic histories of Podocarpium are poorly known due to a lack of fossils in some key regions, such as the Tibetan Plateau, an area recently shown to be crucial for floristic exchanges worldwide in the geological past. Here, we describe well-preserved fossil pods of Podocarpium from the late Eocene (~ 35 Ma) of the Lunpola Basin, central Tibetan Plateau, China. Together with detailed morphological observation and geometric morphology analysis, these fossil pods are named Podocarpium tibeticum W.-C. Li, J. Huang et T. Su sp. nov., characterized by asymmetrical elliptical valves, olecranon fruit beak, and a clearly oblique base. This material comprises the oldest fossil record of Podocarpium from the Tibetan Plateau and adjacent regions. The discovery of P. tibeticum shows Podocarpium was present in central Tibet by the late Eocene. Together with previous fossil records, it indicates that Podocarpium may have originated in East Asia, migrated into the central valley of Tibet in the late Eocene, and then spread westward to Europe through a low-latitude path of island chains along the Neotethys. Results of paleoecological niche modeling demonstrate that Podocarpium had an almost worldwide potential distribution range in the Eocene, but this sharply contracted thereafter until by the Pliocene it was restricted to a small area of East Asia. Generally, this finding further supports the idea that what is now the central Tibetan Plateau was a globally significant hub for Paleogene floristic exchange. • First report of Podocarpium in central Tibetan Plateau. • Shows a new fossil pod species of Podocarpium. • Enhances understanding of its historic distribution globally. • Podocarpium is sensitive for dry and cool climates. [ABSTRACT FROM AUTHOR]