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In this study, we present a new synthesis of GPS velocities for tectonic deformation within the Tibetan Plateau and its surrounding areas, a combined data set of ~1854 GPS-derived horizontal velocity vectors. Assuming that crustal deformation is localized along major faults, a block modelling approach is employed to interpret the GPS velocity field. We construct a 30-element block model to describe present-day deformation in western China, with half of them located within the Tibetan Plateau, and the remainder located in its surrounding areas. We model the GPS velocities simultaneously for the effects of block rotations and elastic strain induced by the bounding faults. Our model yields a good fit to the GPS data with a mean residual of 1.08 mm a-1 compared to the mean uncertainty of 1.36 mm a-1 for each velocity component, indicating a good agreement between the predicted and observed velocities. The major strike-slip faults such as the Altyn Tagh, Xianshuihe, Kunlun and Haiyuan faults have relatively uniform slip rates in a range of 5-12 mm a-1 along most of their segments, and the estimated fault slip rates agree well with previous geologic and geodetic results. Blocks having significant residuals are located at the southern and southeastern Tibetan Plateau, suggesting complex tectonic settings and further refinement of accurate definition of block geometry in these regions. [ABSTRACT FROM AUTHOR]

Using new, daily cloud-free snow-cover products, this study examines snow cover dynamics and their response to climate change. The results demonstrate that the daily cloud-free snow-cover products not only posses the advantages of the AMSR-E (unaffected by weather conditions) and MODIS (relatively higher resolution) products, but are also characterized by high snow and overall classification accuracies (∼85% and ∼98%, respectively), substantially greater than those of the existing daily snow-cover products for all sky conditions and very similar to, or even slightly greater than, those of the daily MODIS products for clear-sky conditions. Using the snow-cover products, we analyzed the snow cover dynamics over the Tibetan Plateau and determined that the maximum number of snow-covered days (SCD) in a year followed a decreasing tendency from 2003 to 2010, with a decrease in snow-covered area (SCA) equivalent to 55.3% of the total Tibetan Plateau area. There is also a slightly increasing tendency in the maximum snow cover area (SCA), and a slightly decreasing tendency in the persistent snow cover area (i.e., pixels of SCD > 350 days) was observed for the 8-year period, which was characterized by increases in temperature (0.09 °C/year) and in precipitation (0.26 mm/year). This suggests that, on the Tibetan Plateau, changes in temperature and precipitation exert a considerable influence on the regional SCD and SCA, as well as the distribution of persistent snow cover. [ABSTRACT FROM AUTHOR]

The monophyly of traditional Aconitum remains unresolved, owing to the controversial systematic position and taxonomic treatment of the monotypic, Qinghai-Tibetan Plateau endemic A. subg. Gymnaconitum. In this study, we analyzed two datasets using maximum likelihood and Bayesian inference methods: (1) two markers (ITS, trnL-F) of 285 Delphinieae species, and (2) six markers (ITS, trnL-F, trnH-psbA, trnK-matK, trnS-trnG, rbcL) of 32 Delphinieae species. All our analyses show that traditional Aconitum is not monophyletic and that subgenus Gymnaconitum and a broadly defined Delphinium form a clade. The SOWH tests also reject the inclusion of subgenus Gymnaconitum in traditional Aconitum. Subgenus Gymnaconitum markedly differs from other species oí Aconitum and other genera of tribe Delphinieae in many non-molecular characters. By integrating lines of evidence from molecular phylogeny, divergence times, morphology, and karyology, we raise the mono-typic A. subg. Gymnaconitum to generic status. [ABSTRACT FROM AUTHOR]

Due to its numerous environmental extremes, the Tibetan Plateau-the world's highest plateau-is one of the most challenging areas of modern human settlement. Archaeological evidence dates the earliest settlement on the plateau to the Late Paleolithic, while previous genetic studies have traced the colonization event(s) to no earlier than the Neolithic. To explore whether the genetic continuity on the plateau has an exclusively Neolithic time depth, we studied mitochondrial DNA (mtDNA) genome variation within 6 regional Tibetan populations sampled from Tibet and neighboring areas. Our results confirm that the vast majority of Tibetan matrilineal components can trace their ancestry to Epipaleolithic and Neolithic immigrants from northern China during the midHolocene. Significantly, we also identified an infrequent novel haplogroup, M16, that branched off directly from the Eurasian M founder type. Its nearly exclusive distribution in Tibetan populations and ancient age (>21 kya) suggest that M16 may represent the genetic relics of the Late Paleolithic inhabitants on the plateau. This partial genetic continuity between the Paleolithic inhabitants and the contemporary Tibetan populations bridges the results and inferences from archaeology, history, and genetics. [ABSTRACT FROM AUTHOR]

As a critical service of terrestrial ecosystem, water regulation (conservation and provision) shows complicated regional heterogeneities due to interactions of various land covers and climate conditions. The widely used valuation methods usually lack accurate descriptions of hydrological responses to multiple land covers, and also ignore their regional differences at large scales. Tibetan Plateau is well known as the Asian water tower with the most diverse and vulnerable ecosystems, and 44 counties in the Brahmaputra, Salween and Lancang River Basins, and Qinghai Region are selected as our study area. The terrestrial ecosystem services are valuated for individual land covers at county scale using improved hydrological simulations for alpine regions (particularly freezing and thawing process simulations of snow cover and glacier), and their regional differences are further identified using multivariate statistical analysis. Results show that runoff hydrographs at most stations are well reproduced with relative bias within ±15%, and average correlation coefficient and efficiency coefficient of 0.88 and 0.72, respectively. The total water regulation values are from US$ 0.59 × 108 to US$ 69.80 × 108 at county scale, accounting for 4.6%–7807.7% of local gross domestic products in the 2015 price level. Thereinto, the water conservation values are the greatest for grass (15.2%–91.2% of total), followed by forest (0.0%–51.3%) and cropland (0.0%–32.4%), while the water provision values are the greatest for glacier (0.0%–80.9%), followed by waterbody (0.0%–38.2%). The water conservation zones of grass, forest and cropland, and the water provision zones of glacier and waterbody are identified, and show obvious regional differences. These zones are in 61.4% of total counties, middle and downstream counties (20.5%), downstream counties of Qinghai Region (4.5%), source counties (9.1%), and middle stream counties of Qinghai Region (4.5%), respectively. This study gives new insights into the valuation of terrestrial ecosystem services in alpine regions, and provides scientific evidence for regional ecological compensations and protection in the Tibetan Plateau. Image 1 • HEQM is improved for water regulation simulations of various land covers. • Water regulation service compositions and their spatial differences are assessed. • Water regulation values are greater than local GDP in 82% of total counties. • Five regulation zones of land covers are identified for 44 counties. • Water conservation zone of grass is dominant in 61.4% of total counties. [ABSTRACT FROM AUTHOR]