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An accurate assessment of the carbon budget is a crucial part of projecting future climate change and its impact on ecosystems. Grasslands foster multiple ecological functions including support for wild animals and livestocks. Herbivores intake forage biomass carbon, then digest and metabolize, and finally retain some carbon. The carbon processes have not been well quantified, resulting in uncertainties in the estimation of regional carbon budgets for grassland ecosystems. An animal metabolic carbon flux model was developed for herbivores in the Three‐Rivers Headwaters region of China. The forage intake and metabolic carbon rates were estimated through metabolic body weight and daily digested measures for the main herbivore species. The carbon intake was 5.52 Tg C year−1(45%) from partial aboveground biomass (12.2 Tg C year−1), in which 39.31% was released into the atmosphere by respiration CO2, 43.77% was returned to the ecosystem as feces and urine, and 16.96% was retained in herbivores for population regeneration or for human well‐being. This study, as the first research on this topic, quantified the carbon flux of herbivores and found livestock accounts for a major part of consumed carbon on grasslands, which is important for understanding regional carbon budgets to mitigate and adapt to climate change over grasslands worldwide. The herbivore carbon budget was estimated by an animal metabolic model developed in the Three‐Rivers Headwaters region. The livestock contributed 88% of the total consumed carbon that was returned 44% to grassland as feces and urine, and 40% through respiration and the remaining 4% in wildlife and 13% in livestock.

Quantifying the elevation dependency of radiation partitioning in high‐altitude mountains is crucial for projecting regional energy balance while remains highly uncertain. We compared the surface radiation partitioning parameters across a meadow (3,200 m), shrub (3,400 m), and forb (3,600 m) along a southern slope of the Qilian Mountains. At a daily scale, the downward shortwave radiation (Rs) fluctuated minimally among the grassland types probably induced by similar site orientations. The greatest downward and upward longwave radiation (Ldand Lu) happened at the lowest meadow while the largest net shortwave (Sn) and longwave (Ln) radiation occurred at the deciduous shrub. The net all‐wave radiation (Rn) of the meadow and shrub was similar and exceeded that of the forb by ∼20%. The differences in Rnbetween the sites were jointly explained by those of upward shortwave radiation (Ru) and Lu, more than by Rsand Ld, suggesting the importance of surface attributes. The monthly normalized effective terrestrial radiation (λ, the ratio of Lnto Rs) varied insignificantly among the sites and averaged 0.25 ± 0.05, which was comparable to the global mean value (0.26). The smallest surface albedo (α, the ratio of Ruto Rs) and largest radiation efficiency (η, the ratio of Rnto Rs) were 0.13 ± 0.02 and 0.64 ± 0.09, respectively, both at the shrub. Grassland type dominated the spatial variations of monthly α and η. These findings highlighted the importance of grassland types to explain the spatiotemporal variations of radiation partitioning parameters in high‐altitude alpine grasslands. An accurate understanding of the radiation budget and partitioning of high‐altitude mountainous regions played a pivotal role in projecting the global climate system. This is especially true in the Qinghai‐Tibetan Plateau, the so‐called “roof of the world”, where there is a large scarcity of high‐quality field observations from different vegetation types. We compared the four‐component radiation measurements of alpine grasslands along an altitudinal gradient (a meadow at 3,200 m, a shrub at 3,400 m, and a forb at 3,600 m) of a southern slope of the Qilian Mountains. We found that the incoming shortwave radiation changed little across the three sites. However, the lowest meadow had the largest incoming and outgoing longwave radiation. The net all‐wave radiation of the meadow and shrub exceeded that of the highest forb. The shrub had the lowest annual surface albedo and the biggest annual radiation efficiency. The annual normalized effective terrestrial radiation fluctuated minimally across the three sites and was comparable to the global mean value. Grassland type was the most important variable responsible for the variations of surface albedo and radiation efficiency. Our findings underscored the importance of taking surface attributes into account when projecting radiation budget and partitioning in high‐altitude alpine grasslands. The differences in net all‐wave radiation were jointly explained by the differences in upward shortwave and longwave radiationThe normalized effective terrestrial radiation was conservative among these grasslands and comparable to the global mean valueGrassland type, more than environmental variables explained the spatiotemporal variations of surface albedo and radiation efficiency The differences in net all‐wave radiation were jointly explained by the differences in upward shortwave and longwave radiation The normalized effective terrestrial radiation was conservative among these grasslands and comparable to the global mean value Grassland type, more than environmental variables explained the spatiotemporal variations of surface albedo and radiation efficiency

Fourteen years data of eddy covariance measurements at an alpine meadow on the Tibetan Plateau (TP) were used to characterise the statistical features of NEE and its relationship with temperature variations. A statistical model was obtained by using the Michaelis-Menten equations of the light-response curve for predicting the NEE for future climate warming. The results show that less than 2 degrees increase of temperature would not have much influence on the CO2absorption amount of the ecosystem, while over 2.6 degrees increase of temperature would change the CO2absorption into CO2release and 4.8 degree increase of temperature would induce a large amount of CO2release from the alpine meadow ecosystem (about 166.8 gC/m2/year). This means that over a 2 degrees warming like RCP8.5 scenario in the future would jeopardise future carbon sink capacity at the alpine meadow ecosystem on the TP.

We have conducted 12-year field observations along two slopes with altitude differences about 1,200 m (3,250 m to 4,400 m and 4,280 m to 5,538 m) to examine the altitudinal dependence of climate warming in recent years. Annual mean of air temperature during 1951-2014 of 65 meteorological stations on the TP are used to analyze the relationship between elevation and climate warming. We divided the TP into three latitude zones: <30°N, 30°N-35°N and >35°N. We find that climate warming rates decreased significantly with elevation increasing in the three latitude zones. Our 12-year intensive field observations data show a similar result. Therefore, higher altitudes are likely to warm slower on the Tibetan Plateau. In addition to the latitudinal effect, it is perhaps largely contributed by the local environmental changes such as urbanization, land cove changes at lower populated elevation area, and/or the glacier and permafrost melting at high mountains.

Permafrost soils store large amounts of carbon. Warming can result in carbon release from thawing permafrost, but it can also lead to enhanced primary production, which can increase soil carbon stocks. The balance of these fluxes determines the nature of the permafrost feedback to warming. Here we assessed decadal changes in soil organic carbon stocks in the active layer—the uppermost 30 cm—of permafrost soils across Tibetan alpine regions, based on repeated soil carbon measurements in the early 2000s and 2010s at the same sites. We observed an overall accumulation of soil organic carbon irrespective of vegetation type, with a mean rate of 28.0 g C m−2yr−1across Tibetan permafrost regions. This soil organic carbon accrual occurred only in the subsurface soil, between depths of 10 and 30 cm, mainly induced by an increase of soil organic carbon concentrations. We conclude that the upper active layer of Tibetan alpine permafrost currently represents a substantial regional soil carbon sink in a warming climate, implying that carbon losses of deeper and older permafrost carbon might be offset by increases in upper-active-layer soil organic carbon stocks, which probably results from enhanced vegetation growth.

Understanding the spatial variation in annual actual evapotranspiration (AET) and its influencing factors is crucial for a better understanding of hydrological processes and water resources management. By synthesizing ecosystem-level observations of eddy-covariance flux sites in China (a total of 61 sites), we constructed the most complete AET dataset in China up to now. Based on this dataset, we quantified the statistic characteristics of AET and water budgets (defined as the ratio of AET to annual mean precipitation (MAP), AET/MAP) of terrestrial ecosystems in China. Results showed that AET differed significantly among both different vegetation types and climate types in China, with overall mean AET of 534.7±232.8 mm yr-1. AET/MAP also differed significantly among different climate types, but there were no distinct differences in AET/MAP values across vegetation types, with mean AET/MAP of 0.82±0.28 for non-irrigated ecosystems. We further investigated how the main climatic factors and vegetation attributes control the spatial variation in AET. Our findings revealed that the spatial variation of AET in China was closely correlated with the geographical patterns of climate and vegetation, in which the effects of total annual net radiation (Rn), MAP and mean annual air temperature (MAT) were dominant. Thus, we proposed an empirical equation to describe the spatial patterns of AET in China, which could explain about 84% of the spatial variation in AET of terrestrial ecosystems in China. Based on the constructed dataset, we also evaluated the uncertainties of five published global evapotranspiration products in simulating site-specific AET in China. Results showed that large biases in site-specific AET values existed for all five global evapotranspiration products, which indicated that it is necessary to involve more observation data of China in their parameterization or validation, while our AET dataset would provide a data source for it.

In this study, we have used four methods to investigate the start of the growing season (SGS) on the Tibetan Plateau (TP) from 1982 to 2012, using Normalized Difference Vegetation Index (NDVI) data obtained from Global Inventory Modeling and Mapping Studies (GIMSS, 1982–2006) and SPOT VEGETATION (SPOT-VGT, 1999–2012). SGS values estimated using the four methods show similar spatial patterns along latitudinal or altitudinal gradients, but with significant variations in the SGS dates. The largest discrepancies are mainly found in the regions with the highest or the lowest vegetation coverage. Between 1982 and 1998, the SGS values derived from the four methods all display an advancing trend, however, according to the more recent SPOT VGT data (1999–2012), there is no continuously advancing trend of SGS on the TP. Analysis of the correlation between the SGS values derived from GIMMS and SPOT between 1999 and 2006 demonstrates consistency in the tendency with regard both to the data sources and to the four analysis methods used. Compared with other methods, the greatest consistency between the in situdata and the SGS values retrieved is obtained with Method 3 (Threshold of NDVI ratio). To avoid error, in a vast region with diverse vegetation types and physical environments, it is critical to know the seasonal change characteristics of the different vegetation types, particularly in areas with sparse grassland or evergreen forest.

The rock art in Fangcheng is mainly made up of various motifs based on cupules on the surface of rocks as well as some others made by carving and grinding. Fangchegn rock art belongs to a part of history, recording early human civilization and is a vivid "history book" carved on rocks. Fangcheng rock art is not only the living memory about ancient civilization but also the root of culture in the Central Plains. Here with the help of experts and scholars who care and love rock art, we are going to explore the connotation of grinding base form rock art and the relationship between it and jade Bi. [ABSTRACT FROM AUTHOR]

The rock art in Fangcheng is mainly made up of various motifs based on cupules on the surface of rocks as well as some others made by carving and grinding. Fangchegn rock art belongs to a part of history, recording early human civilization and is a vivid "history book" carved on rocks. Fangcheng rock art is not only the living memory about ancient civilization but also the root of culture in the Central Plains. Here with the help of experts and scholars who care and love rock art, we are going to explore the connotation of grinding base form rock art and the relationship between it and jade Bi. [ABSTRACT FROM AUTHOR]

Abstract: The identification of easily measured plant functional types (PFTs) that consistently predict grazing response would be a major advance. The responses to grazing of individual traits and PFTs were analyzed along a grazing gradient in an alpine shrub meadow on the Qinghai-Tibet Plateau, China. Three response types were identified; grazing increaser (GI), grazing decreaser (GD), and neutral (NE) for both traits and PFTs. Seven traits were measured: plant height, economic group, cotyledon type, plant inclination, growth form, life cycle, and vegetative structure. The first five were significantly affected by grazing. Ordinal regressions for grazing response of the seven traits showed that the best single predictors of response were growth form (including the attributes “Scattered”, “Bunched” or “Closely Bunched”), and plant inclination (“Rosette”, “Prostrate”, or “Erect”), followed by economic group (“Shrub”, “Grass”, “Sedge”, “Legume”, “Forb”, or “Harmful”) and plant height (“Tall”, “Medium”, or “Small”). Within the four optimal traits, the summed dominance ratio (SDR) of small plants, forbs, rosette and bunched plants, invariably increased, while that of tall plants, shrubs, grasses, and erect plants decreased, when grazing pressure was enhanced. Canonical correspondence analysis (CCA) identified eleven explanatory PFTs based on 195 defined PFTs, by combining the different attributes of the four optimal traits. Among explanatory PFTs, the most valuable in predicting the community response to grazing were Tall×Shrub×Erect×Scattered and Small×Forb×Rosette, as these have the closest connections with grazing disturbance and include fewer species. Species richness, diversity, and community evenness, did not differ among grazing treatments because turnover occurred in component species and their relative abundances along the grazing gradient. We have demonstrated that a minimum set of PFTs resulting from optimal individual traits can provide consistent prediction of community responses to grazing in this region. This approach provides a more accurate indicator of change within a changing environment than do univariate measures of species diversity. We hope to provide a link between management practices and vegetation structure, forming a basis for future, large scale, plant trait comparisons.

The Integrated Environmental Monitoring (IEM) project, part of the Asia-Pacific Environmental Innovation Strategy (APEIS) project, developed an integrated environmental monitoring system that can be used to detect, monitor, and assess environmental disasters, degradation, and their impacts in the Asia-Pacific region. The system primarily employs data from the moderate resolution imaging spectrometer (MODIS) sensor on the Earth Observation System-(EOS-) Terra/Aqua satellite, as well as those from ground observations at five sites in different ecological systems in China. From the preliminary data analysis on both annual and daily variations of water, heat and CO2fluxes, we can confirm that this system basically has been working well. The results show that both latent flux and CO2flux are much greater in the crop field than those in the grassland and the saline desert, whereas the sensible heat flux shows the opposite trend. Different data products from MODIS have very different correspondence, e.g. MODIS-derived land surface temperature has a close correlation with measured ones, but LAI and NPP are quite different from ground measurements, which suggests that the algorithms used to process MODIS data need to be revised by using the local dataset. We are now using the APEIS-FLUX data to develop an integrated model, which can simulate the regional water, heat, and carbon fluxes. Finally, we are expected to use this model to develop more precise high-order MODIS products in Asia-Pacific region.

Alpine wetlands play a sensitive function in global carbon cycle during the ongoing climate warming, yet the temporal patterns of carbon dynamics from in situ ground‐based long‐term observations remain unclear. Here, we analyzed the continuous net ecosystem CO2exchange (NEE) measured with the eddy covariance technique over an alpine peatland on the northeastern Qinghai‐Tibetan Plateau from 2007 to 2016. The wetland acted as a net CO2source with a positive NEE (120.4 ± 34.8 gC m−2year−1, Mean ± SD), with the mean annual gross primary productivity (GPP) of 500.3 ± 59.4 gC m−2year−1and annual ecosystem respiration (RES) of 620.7 ± 74.2 gC m−2year−1. At the seasonal scale, the classification and regression trees (CART) analysis showed that aggregated growing season degree days (GDDs) were the predominant determinant on variations in monthly NEE and monthly GPP. Variations in monthly RES were determined by soil temperature (Ts). Furthermore, nongrowing season Ts had a significant positive correlation with the following year annual GPP (p< 0.05). Nongrowing season RES only accounted for about 25% of annual RES but had significant correlation with annual RES and annual NEE (p< 0.05). The further partial correlation analysis showed that nongrowing season air temperature (Ta, p= 0.05), rather than precipitation (PPT, p= 0.25) was a predominant determinant on variations in annual NEE. Our results highlighted the importance in carbon dynamics of climate fluctuations and CO2emission from the nongrowing season in alpine wetlands. We speculated that the vast peadlands would positively feedback to climate change on the Tibetan plateau where the nongrowing season warming was significant. CO2fluxes in alpine wetland during the nongrowing season were crucial for annual carbon balance of alpine wetlandThe hydrothermal conditions especially during the nongrowing season played crucial role in determining interannual CO2fluxesGlobal warming will exacerbate carbon loss in the alpine wetlands of the Qinghai‐Tibetan Plateau

The rock art in Fangcheng is mainly made up of various motifs based on cupules on the surface of rocks as well as some others made by carving and grinding. Fangchegn rock art belongs to a part of history, recording early human civilization and is a vivid "history book" carved on rocks. Fangcheng rock art is not only the living memory about ancient civilization but also the root of culture in the Central Plains. Here with the help of experts and scholars who care and love rock art, we are going to explore the connotation of grinding base form rock art and the relationship between it and jade Bi. [ABSTRACT FROM AUTHOR]