Uplift of the Tibetan Plateau is ultimately driven by the Cenozoic collision between the Indian and Eurasian plates and their continued convergence. One approach for studying the Tibetan Plateau ...uplift is to verify the paleoelevation changes from collision to present day. This is important for understanding both the tectonics and the climatic effects. The new high resolution palynological record of the uppermost Oligocene to the lowest Miocene strata from the Lunpola Basin indicates that the vegetation types during the latest Oligocene–earliest Miocene were dominated by mixed coniferous–broadleaved forests being different from the modern steppe vegetation. By using the Coexistence Approach to the fossil pollen records, after calibration the effects of temperature difference and the lapse rate, a maximum paleoelevation of 3190±100m asl was estimated in the Lunpola Basin in the latest Oligocene–earliest Miocene, being 1500 to 2000m lower compared with the previous oxygen isotope paleoelevation in the same region.
Display omitted
•Paleoelevation estimation is important for studying Tibetan tectonics.•Providing new time scale for late Oligocene–Miocene strata in central Tibet•Pollen record reveals vegetation evolutions between 26 and 20Ma ago.•A maximum paleo-elevation of 3190m asl in central Tibet was estimated.
Over the past three decades, China has transformed itself from a
stagnant, inward, centrally planned economy into an animated,
outward-looking, decentralized market economy. Its rapid growth and
...trade surpluses have caused uneasiness in Western governments,
which perceive this growth to be a result of China's rejection of
international protocols that protect intellectual property and its
widespread theft and replication of Western technology and
products. China's major trading partners, particularly the United
States, persistently criticize China for delivering, at best,
half-hearted enforcement of intellectual property rights (IPR)
norms. Despite these criticisms, Zhenqing Zhang argues that China
does respect international intellectual property rights, but only
in certain cases. In Intellectual Property Rights in
China , Zhang addresses the variation in the effectiveness of
China's IPR policy and explains the mechanisms for the uneven
compliance with global IPR norms.
Covering the areas of patent, copyright, and trademark, Zhang
chronicles how Chinese IPR policy has evolved within the legacy of
a planned economy and an immature market mechanism. In this
environment, compliance with IPR norms is the result of balancing
two factors: the need for short-term economic gains that depend on
violating others' IPR and the aspirations for long-term sustained
growth that requires respecting others' IPR. In case studies
grounded in theoretical analysis as well as interviews and
fieldwork, Zhang demonstrates how advocates for IPR, typically
cutting-edge Chinese companies and foreign IPR holders, can be
strong enough to persuade government officials to comply with IPR
norms to achieve the country's long-term economic development
goals. Conversely, he reveals the ways in which local governments
protect IPR infringers because of their own political interests in
raising tax revenues and creating jobs.
Although many studies have attempted to reconstruct millennial‐scale hurricane patterns using various proxy‐based methods, it is still unclear what the most effective proxies are to identify storm ...surge deposits in different environmental settings. This study quantitatively compares the application of grain‐size, loss‐on‐ignition, stable isotopes, X‐ray fluorescence, and palynological proxies in paleotempestology from an organic‐rich environment in the Florida Everglades. The nonparametric tests indicate that only 9 among the 27 parameters (mean diameter, %water, %organic, %carbonate, Ca, Sr, Ca/Ti, Cl/Br, and marine microfossils) exhibited significant differences between storm‐surge and in situ deposits. The principal component analysis shows that five marine indicators (Sr, Ca, Ca/Ti, %Carbonate, and Marine microfossils) have the closest association with the allochthonous samples, while Cl/Br and Mz are the most sensitive proxies in low‐ and high‐energy environments, respectively. Moreover, organic geochemical proxies (e.g., δ13C and δ15N of bulk sedimentary organic matter) are ineffective for identifying storm‐surge deposits in organic‐rich mangrove environments.
Plain Language Summary
To help objectively identify the occurrence of storm‐surge deposits in coastal sediment cores, this study uses a statistical approach to evaluate the effectiveness of 27 widely used sedimentological, organic and inorganic geochemical, and biological parameters in distinguishing allochthonous deposits from autochthonous deposits in an organic‐rich environment in the Florida Everglades. The results show that Ca, Sr, Ca/Ti, and marine microfossil are four of the most sensitive parameters to distinguish storm‐surge deposits in organic‐rich environments in south Florida. In addition, Cl/Br can be used to indicate storm surge inundation in further inland and lower‐energy environments. Moreover, organic geochemical proxies cannot effectively distinguish storm‐surge deposits from in situ deposits in mangrove‐dominated coastal zones. Future studies need to explore the use of more specific organic geochemical proxies (e.g., biomarker) in mangrove‐dominated environments and evaluate the effective proxies in detecting storm deposits from sandy, deltaic/estuarine, and nontropical coastal environments.
Key Points
Ca, Sr, Ca/Ti, and marine microfossil are the most sensitive parameters to identify storm‐surge deposits in organic‐rich environments
Cl/Br can be used to indicate storm surge inundation in further inland and lower energy environments
Organic geochemical proxies cannot effectively distinguish storm‐surge deposits from in situ deposits in mangrove‐dominated coastal zones
Zhenqing Zhang argues that China does respect international intellectual property rights, but only in certain cases. In Intellectual Property Rights in China, he addresses the variation in the ...effectiveness of China's IPR policy and explains the mechanisms for the uneven compliance with global IPR norms.
A high-resolution pollen record in a peat sequence from the Altai Mountains of Xinjiang, China, allows reconstruction of the regional vegetation and climate changes that occurred during the Holocene. ...Pollen distributions from the sequence indicate that the vegetation community in the Altai Mountains region transitioned through five general phases: forest and desert steppe, wet steppe, desert steppe, steppe, and finally forest and desert steppe. These vegetative phases imply that the regional climate changed from a cold and dry early Holocene to a warmer and wetter early-mid Holocene and then to a cold and rather dry mid-Holocene that was followed by a cool and wet late Holocene and finally by warm and dry conditions for the last millennium. These regional changes in climate are roughly consistent with local changes previously reconstructed from organic geochemical paleoclimate proxies in the same peat sequence by Zhang et al. (2016), but with some minor but important differences that reflect local factors.
Regional comparisons reveal that the Holocene climate changes in the Altai Mountains are generally consistent with those of most arid central Asian regions that are influenced mainly by westerlies. However, they are out-of-phase with the climate histories of regions controlled by the Asian monsoons, indicating that the Asian monsoons did not extend to the high-altitude mountain regions of arid central Asia during the Holocene. We postulate that the regional Holocene moisture variations have been mainly modulated by NAO variations that affected transport of water vapor from the North Atlantic Ocean by the westerlies. Moreover, local factors that include topography of the mountains and glacial meltwater events in the high-altitude regions also contributed to the climate changes in the Altai Mountains. In addition, air temperatures related to summer insolation of the Northern Hemisphere might have played an important role in modulating moisture in the region, but only after the local montane ice-sheets had disappeared by the mid-Holocene.
•Pollen records from a peat sequence from Xinjiang Altai Mountains reveal Holocene vegetation changes.•Pollen-based reconstruction of Holocene climate changes in the Altai Mountains.•Comparisons of Holocene climate changes in Altai Mountains with arid central Asian and monsoonal Asian regions.•Explanations proposed for Holocene vegetation and climate changes in the Altai Mountains.
Propagation of faults and folds in the foreland basins of Tian Shan is an important process accommodating Cenozoic crustal shortening and mountain building, but little is known about the accurate ...time of the Cenozoic tectonic deformation. Based on growth strata and age determination, we show that syntectonic growth strata began to develop in the middle part of Tian Shan since 6 Ma ago. Geometry analysis indicates that formation of the growth strata is associated with progressive fold-limb rotation. Formation of the growth strata is contemporaneous with the tectonic deformation in the thrusting and folding zones. Together with the remarkable increase of sedimentation rate as well as the accumulation of coarse molasse deposits, we conclude that the late Cenozoic crustal shortening and mountain building in the region initiated since about 6 Ma and lasted to the early Pleistocene, as a consequence of intracontinental deformation within the India–Eurasia convergent system.
Understanding the historical flooding regime and its driving mechanisms provide useful insights into prediction of disasters in future. In this study, the paleo-flooding activities along the upper ...Amur River Delta were reconstructed based on the grain-size dataset of three sedimentary cores along a 120-km transect from its alluvial valley. Our results indicate that the coarse sand fraction in marshes surrounding the upper Amur River Delta is closely linked to historical flooding activities. Six “busy” flooding periods were identified at 4.4–4.0 ka BP, 3.6–3.2 ka BP, 1.7–1.4 ka BP, 1.1–0.9 ka BP, 0.7–0.5 ka BP, and 0.2–0 ka BP, respectively. These flooding intervals correspond well to other sedimentary flooding records from the East Asia Summer Monsoon (EASM) domain, and are in-line with the strengthened EASM stages throughout the Late-Holocene. Thus, our dataset suggests that the EASM circulation, especially its associated precipitation, has played a critical role in the evolution of flooding regime during the Late-Holocene epoch in the Amur River Delta. The last 0.2 ka BP is an exception as the coarse sand accumulation rate increased significantly while the EASM precipitation shows no equivalent shift. The increased coarse sand signals were likely attributed to floods induced by human interference instead of the long-term climate influence.
Display omitted
•The coarse sand fraction in marshes surrounding the Amur River is closely linked to historical flooding activities.•Six “busy” flooding periods were identified at 4.4-4.0, 3.6-3.2, 1.7-1.4, 1.1-0.9, 0.7-0.5, and 0.2-0 ka BP.•The Historical flooding activities in our study region were primarily controlled by EASM associated precipitation.•The flooding-rich period over the last 200 years was ascribed to human disturbance.
Monosaccharide analysis is a critical way to profile the composition of complex carbohydrates. Methods to analyze neutral and amino sugars have been established for a long time, but methods for ...acidic sugars are rare. The acidic sugars, including uronic acids and sialic acids, are also important components in some complex carbohydrates. In this report, a high-performance anion-exchange chromatography method with pulsed amperometric detection was initially developed to analyze acidic sugars including different uronic acids and sialic acids. Subsequently, a method to profile complete monosaccharides, including most neutral, amino, and acidic sugars, was developed. This method has a limit of quantitation of ~12.5 × 10(-3) nmol for each sugar as well as good linearity over a wide range. This is a convenient procedure because it avoids additional derivatization of monosaccharides and has a broad application to a wide range of complex carbohydrates. The monosaccharide compositions of a variety of complex carbohydrates such as different glycosaminoglycans, alginate, fucoidan, and glycans were profiled by this comprehensive method. In addition, the hydrolysis patterns of these complex carbohydrates are discussed.
This work aims to investigate the effect of additional flue gas desulfurization gypsum (FGDG) on the properties of calcium sulfoaluminate cement (CSAC) blended with ground granulated blast furnace ...slag (GGBFS). The hydration rate, setting time, mechanical strength, pore structure and hydration products of the CSAC-GGBFS mixture containing FGDG were investigated systematically. The results show that the addition of FGDG promotes the hydration of the CSAC-GGBFS mixture and improves its mechanical strength; however, the FGDG content should not exceed 6%.
Schematic figure showing climate driving mechanisms on wetland hydrological and vegetational evolution. The relatively strong East Asian summer monsoon (EASM) with high precipitation tends to ...generate a higher water-level condition with more hygrophilous herbaceous plants while blocking the deposition of coarse grain-size fractions (a), and vise versa for weak EASM stages (b).
Display omitted
•The late-Holocene hydrological and vegetational regimes were reconstructed.•An ecological lake-to-wetland transition occurred at ~4.5 ka BP.•The wetlands evolution was largely controlled by monsoonal precipitation.
The responding mechanism of wetland ecosystem to climate change is currently unclear due to a lack of long-term records incorporating multiple ecological factors. This paper presents a well-dated and multi-proxy cored record from a natural freshwater wetland developed in a paleo-pingo-related depression on the Sanjiang Plain. The study aims to reconstruct the wetland water-level and vegetational regimes during the past ~6.0 ka BP and discuss the wetland evolution response to the East Asian summer monsoon (EASM) circulation. The results show that a shallow-water lake with hygrophilous herbs developed in the depression with a strong EASM during ~6.0–4.5 ka BP. The paleolake was succeeded by a wetland with a lowered mean water level and an increase in tree cover controlled by the weakened EASM during the past 4.5 ka BP. Such an ecological lake-to-wetland transition corresponds well to the sharp decline of the EASM around 4.5 ka BP which has been well documented in various geological records across the EASM domain. During the wetland developing stage over the past 4.5 ka BP, the water-level and vegetational changes in the studied depression were also closely related to the EASM variations. The strengthened EASM usually generated higher water levels with more hygrophilous herbs around 4.0 ka BP, 3.5 ka BP, 3.0 ka BP, 2.0 ka BP, and 1.3 ka BP. Considering the prevalent EASM climate serving as the predominant water supply for the wetlands on the modern Sanjiang Plain, we suggest the EASM circulation has played a critical role in driving the wetland ecological evolution during the mid-to-late Holocene Epoch. The past 0.4 ka BP is an exception as the local Trees/Herbs ratio visibly increased with the declined water level, while the monsoonal precipitation shows no equivalent shift. The wetland evolution at this stage was attributed to human interference.
PDF
