Diversity of primary vegetation species of lake shore impacts largely carbon emissions in thermokarst lakes on the Qinghai-Tibet plateau.

Terrestrial organic matter from surrounding primary vegetation is critical for carbon cycling in thermokarst lakes. However, the characteristics and contribution of this vegetation in shaping microbial community and affecting carbon emissions in thermokarst lakes remain poorly understood. This study quantifies the influence of lakeshore primary vegetation characteristics on microbial community and carbon emissions across lakes with different vegetation types on the Qinghai-Tibet Plateau (QTP).

Fifty percent overestimation of black carbon concentration measured in aerosols of the Tibetan Plateau.

Elemental carbon (EC), also known as black carbon, plays an important role in climate change. Accurately assessing EC concentration in aerosols remains challenging due to the overestimations caused by carbonates and organic carbon (OC) during thermal-optical measurement in the Tibetan Plateau (TP). This study evaluates the extent of EC overestimated by carbonates and OC at four remote sites (Nyalamu, Lulang, Everest and Ngari) in southern and western of the TP using different treatments.

Temperature sensitivity of methanogenesis and anaerobic methane oxidation in thermokarst lakes modulated by surrounding vegetation on the Qinghai-Tibet Plateau.

Understanding the balance between methane (CH) production (methanogenesis) and its oxidation is important for predicting carbon emissions from thermokarst lakes under global warming. However, the response of thermokarst lake methanogenesis and the anaerobic oxidation of methane (AOM) to warming, especially from Qinghai-Tibetan Plateau (QTP), is still not quantified. In this study, sediments were collected from 11 thermokarst lakes on the QTP.

Fatigue life prediction of cracked cross beam of mining linear vibrating screen under cyclic load.

The cross beam of a mining linear vibrating screen is prone to cracking under long-term cyclic load. In order to accurately predict the fatigue life of the cracked cross beam, a coupled analysis method of vibration and crack propagation is proposed. A 2D dynamic model of the vibrating screen is established based on the finite element method, which is verified by the vibration test platform.

Dynamics of a cross beam with a straight crack in a mining linear vibrating screen.

Cross beam fracture is one of the common failures of vibrating screens, and crack is the early manifestation of fracture, which is hard to detect. In order to meet the screening requirement of the vibrating screen and improve the service life of the cracked beam, the cracked Euler-Bernoulli beam model is established to investigate the dynamics of the cross beam with a straight crack under different weights of eccentric block, processing capacities, and Rayleigh damping coefficients based on the finite element method in this paper. The local flexibility coefficients are derived from the principles of fracture mechanics and strain release energy and solved by the adaptive five-point Gaussian Legende algorithm.

Characteristics of methane and carbon dioxide in ice caves at a high-mountain glacier of China.

The exploration of the spatiotemporal distribution of greenhouse gas (GHG) exchange in the cryosphere (including ice sheet, glaciers, and permafrost) is important for understanding its future feedback to the atmosphere. Mountain glaciers and ice sheets may be potential sources of GHG emissions, but the magnitude and distribution of GHG emissions from glaciers and ice sheets remain unclear because observation data are lacking. In this study, in situ CH and CO and the mixing ratios of their carbon isotope signatures in the air inside an ice cave were measured, and CH and CO exchange in the meltwater of Laohugou glacier No.

Weak transport of atmospheric water-insoluble particulate carbon from South Asia to the inner Tibetan Plateau in the monsoon season.

Carbonaceous particles play a crucial role in atmospheric radiative forcing. However, our understanding of the behavior and sources of carbonaceous particles in remote regions remains limited. The Tibetan Plateau (TP) is a typical remote region that receives long-range transport of carbonaceous particles from severely polluted areas such as South Asia.

Displacement of mining vibrating screen obtained from acceleration based on improved S-G filter.

Vibration displacement is one of the key parameters in fault diagnosis of vibrating screens. Monitoring of acceleration signals of vibrating screens can be disturbed due to various factors such as on-site working conditions and equipment. In order to obtain accurate displacement signals of vibrating screen, the method for converting vibration acceleration to displacement based on improved Savitzky-Golay (S-G) filter is proposed.

Significant spatial variations of the atmospheric environment at remote site of the Tibetan Plateau - a case study on major ions of precipitation around Nam Co station.

Remote region is normally considered a receptor of long-range transported pollutants. Monitoring stations are important platforms for investigating the atmospheric environment of remote regions. However, the potential contribution of very local sources around these stations may produce important influences on its atmospheric environment, which is still barely studied.

Dust dominates glacier darkening across majority of the Tibetan Plateau based on new measurements.

Rapid retreat and darkening of most glaciers in the Tibetan Plateau (TP) are enhanced by the deposition of light-absorbing particles (LAPs). Here, we provided new knowledge on the estimation of albedo reduction caused by black carbon (BC), water-insoluble organic carbon (WIOC), and mineral dust (MD), based on a comprehensive study of snowpit samples from ten glaciers across the TP collected in the spring of 2020. According to the albedo reductions caused by the three LAPs, the TP was divided into three sub-regions: the eastern and northern margins, Himalayas and southeastern TP, and western to inner TP.

Importance of precipitation and dust storms in regulating black carbon deposition on remote Himalayan glaciers.

Black carbon (BC) can be transported over long distances and is an important trigger of climate warming and glacier melting at remote high mountains and polar regions. It is normally assumed that the variation of BC flux in remote regions is dominated by its emissions. However, after a comprehensive investigation of potential influencing factors on temporal variations of BC from ice cores of the Himalayas, this short communication shows that in addition to BC emissions, contributions from dust storms and precipitation are also important (up to 56% together) in regulating the variation of BC deposition flux and concentrations derived from remote Himalayan ice core measurements.

South Asian black carbon is threatening the water sustainability of the Asian Water Tower.

Long-range transport of black carbon from South Asia to the Tibetan plateau and its deposition on glaciers directly enhances glacier melt. Here we find South Asian black carbon also has an indirect effect on the plateau's glaciers shrinkage by acting to reduce the water supply over the southern Tibetan plateau. Black carbon enhances vertical convection and cloud condensation, which results in water vapor depletion over the Indian subcontinent that is the main moisture flux source for the southern Tibetan plateau.

Concentrations, sources, fluxes, and absorption properties of carbonaceous matter in a central Tibetan Plateau river basin.

Carbonaceous matter (CM) (such as water-insoluble organic carbon (WIOC), black carbon (BC), and water-soluble organic carbon (WSOC)) has a significant impact on the carbon cycle and radiative forcing (RF) of glacier. Precipitation samples and glacier's snow/ice samples (snowpit, surface snow, and granular ice) (Xiao dongkemadi Glacier) were collected at the Dongkemadi River Basin (DRB) in the central Tibetan Plateau (TP) between May and October 2016 to investigate the characteristics and roles of CM in the TP River Basin. WIOC, BC, and WSOC concentrations in precipitation were relatively higher than that in snowpit, but lower than that in surface snow/ice, with the wet deposition fluxes of 0.

Importance of local non-fossil sources to carbonaceous aerosols at the eastern fringe of the Tibetan Plateau, China: ΔC and δC evidences.

Carbonaceous particles are an important radiative forcing agent in the atmosphere, with large temporal and spatial variations in their concentrations and compositions, especially in remote regions. This study reported the ΔC and δC of total carbon (TC) and water-insoluble particulate carbon (IPC) of the total suspended particles (TSP) and PM at a remote site of the eastern Tibetan Plateau (TP), a region that is influenced by heavy air pollution from Southwest China. The average organic carbon and elemental carbon concentrations of TSP samples in this study were 3.

Composition and sources of heavy metals in aerosol at a remote site of Southeast Tibetan Plateau, China.

Knowledge of the elemental composition of aerosols at remote sites is important for evaluating the influence of anthropogenic activities. In this study, the elemental composition and sources of total suspended particles (TSP) at Yaze, a remote site in the southeastern Tibetan Plateau (TP), were investigated. The results showed that the mean elemental concentrations at Yaze were relatively low compared with those in other areas of the TP.

Molecular compositions, optical properties, and implications of dissolved brown carbon in snow/ice on the Tibetan Plateau glaciers.

Brown carbon (BrC)/water-soluble organic carbon (WSOC) plays a crucial role in glacier melting. A quantitative evaluation of the light absorption characteristics of WSOC on glacier melting is urgently needed, as the WSOC release from glaciers potentially affects the hydrological cycle, downstream ecological balance, and the global carbon cycle. In this work, the optical properties and composition of WSOC in surface snow/ice on four Tibetan Plateau (TP) glaciers were investigated using a three-dimensional fluorescence spectrometer and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry.

An overestimation of light absorption of brown carbon in ambient particles caused by using filters with large pore size.

As an important component of carbonaceous particles, organic carbon (OC) plays a significant role in radiative forcing in the atmosphere. Recently, the warming effect of light-absorbing OC has been emphasized. Water-soluble organic carbon (WSOC) is commonly used as a surrogate to investigate the light absorption of OC.

Overestimation of anthropogenic contribution of heavy metals in precipitation than those of aerosol samples due to different treatment methods.

Due to increased anthropogenic activities in recent decades, many heavy metal elements have been emitted into the atmosphere and transported to remote regions. The Enrichment factors (EFs) is a normally used method for evaluating the source of heavy metal elements. However, because of some flaws of this method (e.

Coupling of decreased snow accumulation and increased light-absorbing particles accelerates glacier retreat in the Tibetan Plateau.

Most glaciers in the Tibetan Plateau (TP) are experiencing dramatic retreat, which is resulting in serious environmental and ecological consequences. In addition to temperature increases, increased light-absorbing particles (LAPs) and decreased precipitation were proposed to, independently, play important roles in reducing glacier accumulation. Based on investigations of effect from an extremely low precipitation event in the TP and surrounding regions caused by La Niña from October 2020 to April 2021, a new mechanism was provided.

Photobleaching reduces the contribution of dissolved organic carbon to glacier melting in the Himalayas and the Tibetan Plateau.

Dissolved organic carbon (DOC) makes an important contribution to glacier melting in the Himalayas and the Tibetan Plateau (HTP). Photobleaching can effectively reduce the light absorption ability of DOC, further changing its impact on glacier melting, which is not yet well researched in the HTP. Therefore, snowpit samples from the Bayi, Ganglongjiama (GLJM), Jiemayangzong (JMYZ) and Demula (DML) glaciers were collected to study the influence of photobleaching on the light absorption ability of DOC and its impact on glacier melting.

Mercury sources and physicochemical characteristics in ice, snow, and meltwater of the Laohugou Glacier Basin, China.

In this work, samples of surface snow, surface ice, snow pit and meltwater from the Laohugou Glacier No. 12 on the northern edge of Tibetan Plateau (TP) were collected during the summer of 2015. The average concentration of Hg in surface snow/ice was 22.