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Regional culture of the Qinling Mountains shows distinct features since it was born in the local outstanding ecological environment, study on local architecture is significant for the dominant expression of regional culture, protection of local environment, and echoing with the theme of ecological civilization construction. This paper, on the basis of the mutual influence and evolution of regional culture and style of local residential buildings, explored the reasons for the weakening of local architectural style, and specified the significance of promoting local style of the living environment. By studying the influence of local natural environment and humanistic environment on architectural style along the northern foot of the Qinling Mountains, the paper explored the expression of regional culture in residential buildings, with Xian Garden (Xi'an Yuanzi) as an example, and aimed at giving useful help to the dominant expression of regional culture in modern residential buildings. [ABSTRACT FROM AUTHOR]

Forty-nine wild oil plants which are abundant in the Tsinling and Zhongtiao Mountains were investigated and screened as raw material for biodiesel production. The oil content was tested and found to be greatly variable, ranging from 10 to 62.8 %. Fatty acid profiles of their vegetable oils were analyzed, and their acid value, saponification number, and iodine value were found to range from 1.6 to 61.3 mg KOH/g, 128.6 to 225.9 mg KOH/g, and 54.3 to 120.9 g I/100 g, respectively. Cetane number, kinematic viscosity, specific gravity, high heating values, and cold filter plugging point of the 49 vegetable-oil methyl esters (MEs) were empirically calculated and were found to vary from 38.8 to 66.6, 2.9 to 4.2 mm/s, 841.4 to 883.8 kg/m, 39.0 to 47.5 kJ/g, and −14.3 to 13.2 °C, respectively. Almost half (25 species) of all the sampled resources were found to be suitable for biodiesel production since the profiles of their vegetable-oil MEs met the major specifications of Chinese and European Union biodiesel standards, GB/T20828 and EN-14214, respectively. Grey relational analysis was used during the optimum-species screening process. The difference between the individual species and the artificial designed ideal species (the best biodiesel plant type in this paper) was calculated and evaluated with the help of grey relational grade, which varied from 0.467 to 0.686. Finally, the selected plants, Prunus salicina Linn. and Amygdalus davidiana (C.) C. de Vos, were considered as the optimal feedstock for biodiesel production. [ABSTRACT FROM AUTHOR]

The relationship between temperature and drought was investigated using the temperature-sensitive growth of Larix chinensis Beissn in the Qinling Mountains, central China. Extremely high tree-ring width index values (TRWI) agreed well with dry conditions defined by the dryness-wetness index (DWI) obtained from data in Chinese historical documents and climate-related papers between 1814 and 1956 (before the short of instrumental measurements); the reverse applied to extremely low TRWI values. The main severe drought epochs occurred from the late 1850s to the 1870s, the 1920s to 1930s and in the 2000s, whereas wet spells occurred from 1817-1827 and 1881-1886. The droughts in the 2000s exhibited a similar pattern as the ones from the 1920s to 1930s, with obviously an increasing temperature. The variation of tree growth agreed well with other reconstructed temperature series from nearby and remote regions, suggesting that Larix chinensis could respond to broad-scale climate variability. The longest cold interval, 1817-1827, could be associated with the influence of the Tambora eruption in 1815. [ABSTRACT FROM AUTHOR]

Appraisal of tourism development planning is a core link tot its authoritativeness and legalization. Currently, China's appraisal work is mainly confined to qualitative analysis and presents "pro forma" irrational phenomena. The paper constructs 25-index appraisal system from the 4 levels of standardization, scientification, feasibility and innovation and takes tourism development planning in Qinling Mountains, Shananxi Province as an empirical study. The results show that 1. the appraisal system is composed of compiling system, planning object system and management system and the appraisal stakeholders are divided into core stakeholders and fringe stakeholders; 2. feasible index weighs the most, at the core position, followed by scientific index, as the key target of examination and appraisal; innovative index places the third, attention is paid to the planning contents and technical innovation and standardized index weighs the least, which is closely related to planning forms and content system; 3. demonstration link of the results of tourism development should be increased to carry on the evaluation ways combining qualitative, quantitative and grading contents and develop the management system. [ABSTRACT FROM AUTHOR]

A checklist of 63 species of tardigrades from the Tsinling Mountains is given in this paper. Thirty-seven species of tardigrades that had never been found in the Tsinling Mountains were reported here. Twenty of them are new records for the mountains, 15 of them are new records for China, two of them are new to science. Pseudechiniscus pilatoi sp. n. is similar to Pseudechiniscus quadrilobatus Iharos, 1969. It differs from P. quadrilobatus in different cuticular sculpture, in the joints of paired-plates, near the dorsal median line, uplifting but not protruding backward, and in lacking notches on terminal plate. Echiniscus marleyi sp. n. differs from E. canadensis Murray in having filaments D; it differs from E. mediantus Marcus in lacking filaments C but in having filaments D; it differs from E. spinulosus (Doyère) in lacking teeth B, C, E, and in having filaments D instead of teeth D. [ABSTRACT FROM AUTHOR]

Abstract: The Qinling Mountains provide a natural boundary between the north and south parts in China, and support a huge variety of plants and wildlife. However, the research on the vegetation history of Qinling forests has remained a blank. In order to choose the most suitable tree species to restore the Qinling forests, it is necessary to carry out studies on the history of forest vegetation in the area. Swamp sediments of mountain basins can store pollen from different historical periods in various levels. Through research on the deposition age of particular sediments in different levels and the characteristics of the pollen assemblage, we can understand the history of the forest vegetation in the area and further provide the scientific basis for the proper management of forests. In this paper, we have divided the vegetation history and climatic variations in the Qinling Mountains into four stages based on the pollen analysis and 14C age determination of a swamp sediment profile of mountain basins at an altitude of 2200 m as well as the pollen analysis on surface soil. In Stage 1 (18,715–7629 cal BP), the vegetation was composed of Abies and Picea. The climate was cold and humid. In Stage 2 (7629–3131 cal BP), the vegetation was dominantly Abies, Picea, Betula, Quercus and Alnus. The climate was warm and humid. During Stage 3 (3131–50 cal BP), the vegetation was dominantly Abies. The climate was cold and humid. During Stage 4 (0–50 cal BP), the vegetation was dominantly Betula, Quercus, Corylus, Alnus, and Tsuga, with fewer Pinus as well as groups of Abies. The climate was warm and dry. There is a noticeable decrease of Abies and Picea in accordance with a climate change from cold and humid to warm and dry. We also noticed an increase of Betula, Quercus, Corylus, Alnus, and Tsuga, which prefer warm and dry environments. [Copyright &y& Elsevier]

In this paper, we present a δ13C record that covers the past 750 years at a resolution of 2 - 3 years which was preserved in a precisely dated stalagmite (DY-1) obtained from the Dayu Cave on the south flank of the Qinling Mountains in central China. Between 1249 AD and 1800 AD, climate-induced vegetation changes appear to have been the primary control on δ13C values at a centennial scale. Variations in precipitation amounts control the residence time of seepage water and may have affected the dissolution of bedrock, prior carbonate precipitation in the unsaturated zone above the cave, and the degassing of CO2 within the cave. These hydrogeochemical processes are likely to have been the most important controls on δ13C levels over annual to decadal scales, and may also have influenced centennial-scale variations. The reduced δ13C value of atmospheric CO2 since the Industrial Revolution may have caused the decreasing trend in δ13C values seen in stalagmite DY-1 after 1800 AD. Increased visitor numbers in the unventilated Dayu Cave over time produced a large amount of CO2, and maintained a raised level of pCO2 in the cave air. This artificially enhanced pCO2 may have decreased the fraction of CO2 degassing, and hence carbonate precipitation, which could partly cause the decreasing trend in the stalagmite δ13C seen over the past 200 years. [ABSTRACT FROM AUTHOR]

Abstract: Loess deposits in the Eastern Qinling Mountains (central China) provide a detailed archive for reconstructing the paleoenvironment during early hominin occupation. The study of the loess deposits also provides a unique opportunity to understand Pleistocene atmospheric circulation in this transitional climatic zone. However, the provenance and formation of the loess deposits were not well understood until now. In this paper, we report on new geomorphologic investigations and depositional analyses of the loess deposits. The results suggest that Gobi deserts and drylands in northern and northwestern China were one of the dust sources. These loess deposits show similar geochemical composition as the average upper crust (UCC), and may indicate that they experienced multiple sedimentary processes, with the dust being well mixed before deposition. However, the higher 87Sr/86Sr ratios (between 0.719650 and 0.721043) and extremely low ɛNd(0) values (between −11.98 and −18.97), which are different from the typical loess of the Chinese Loess Plateau, demonstrate that proximal clastic sediments that were apparently derived from the weathered Qinling orogen bedrocks, form the other important source for the loess deposits. The chemical Index of Alteration [CIA = Al2O3/(Al2O3 + CaO* + Na2O + K2O) × 100] and Chemical Proxy of Alteration [CPA = 100 × Al2O3/(Al2O3 + Na2O)], both in molar proportions show that the loess has experienced intense pedogenesis. We conclude that the loess deposit has a mixed provenance. The palaeoclimate in the Eastern Qinling Mountains remained mild in the glacial periods due to the topography and unique geographic locations, providing a suitable place for hominine occupation. [Copyright &y& Elsevier]

Abstract: The western Qinling is characterized by Triassic granitic plutons, which are keys to constrain the timing of subduction and collisional processes between the North China and South China Blocks. This paper presents a set of new LA-ICPMS U–Pb zircon geochronology, major and trace element geochemistry for several representative diorite and granitoid plutons in the Foping area. The diorites are characterized by high MgO, Al2O3, Y and Yb contents, but low SiO2, Sr/Y and La/Yb ratios, as well as depletion of Nb, Ta, P and Ti, suggesting derived from a subduction related setting. LA-ICPMS zircon U–Pb age of 216.9±1.5Ma (MSWD=0.69) from the diorite constrains the time of the subduction event. The medium- and fine-grained monzogranites as well as the biotite granites exhibit relative high SiO2, MgO and Rb, low Y and Yb contents, and low Sr/Y and La/Yb ratios, as well as various depletions of Nb, Ta, P and Ti. These features indicate a derivation from lower continental crust but had been influenced by slab released fluids in a syn-collisional setting. The medium-grained monzogranite and biotite granite yield LA-ICPMS zircon U–Pb ages of 207.3±2.1Ma (MSWD=1.8) and 201.6±1.2Ma (MSWD=1.04), respectively, proposing the syn-collision during ca. 207–201Ma. Geochemical and geological evidences suggest that the granodiorites intruding in the syn-collisional monzogranites were related to the post-orogenic collapse after the collision between the North China and South China Blocks. The LA-ICPMS U–Pb zircon age of 189.3±2.9Ma (MSWD=5.6) for the granodiorite constrains the time of the post-orogenic collapse. Our geochronological and geochemical data provide important constraints on the Triassic evolution from subduction to collision then up to post-collisional collapse along the Qinling orogen. [Copyright &y& Elsevier]

Abstract: East Qinling is the largest porphyry molybdenum province in the world; these Mo deposits have been well documented. In West Qinling, however, few Mo deposits have been discovered although granitic rocks are widespread. Recently, the Wenquan porphyry Mo deposit has been discovered in Gansu province, which provides an insight into Mo mineralization in West Qinling. In this paper we report Pb isotope compositions for K-feldspar and sulfides, S isotope ratios for sulfides, the results obtained from petrochemical study and from in situ LA-ICP-MS zircon U-Pb dating and Hf isotopes. The granitoids are enriched in LILE and LREE, with REE and trace element patterns similar to continental crust, suggesting a crustal origin. The Mg# (40.05 to 56.34) and Cr and Ni contents are high, indicating a source of refractory mafic lower crust. The ε Hf(t) values of zircon grains from porphyritic monzogranite range from −2.9 to 0.6, and from granitic porphyry vary from −3.3 to 1.9. The zircons have T DM2 of 1014 to 1196Ma for the porphyritic monzogranite and 954 to 1224Ma for the granitic porphyry, implying that these granitoids were likely derived from partial melting of a Late Mesoproterozoic juvenile lower crust. The Pb isotope compositions of the granitoids are similar to granites in South China, showing that the magma was sourced from the middle–lower crust in the southern Qinling tectonic unit. The Pb isotopic contrast between the Mo-bearing granitoids and ores shows that the Pb in the ore-forming solution was derived from fractionation of a Triassic magmatic system. δ34S values of sulfides are between 5.02 and 5.66‰, similar to those associated with magmatic-hydrothermal systems. LA-ICP-MS zircon U-Pb dating yields crystallization ages of 216.2±1.7 and 217.2±2.0Ma for the granitoids, consistent with a previously reported molybdenite Re-Os isochron age of 214.4±7.1Ma. This suggests that the Mo mineralization is related to the late Triassic magmatism in the West Qinling orogenic belt. In view of these geochemical results and known regional geology, we propose that both granitoid emplacement and Mo mineralization in the Wenquan deposit resulted from the Triassic collision between the South Qinling and the South China Block, along the Mianlue suture. Since Triassic granitoid plutons commonly occur along the Qinling orogenic belt, the Triassic Wenquan Mo-bearing granitoids highlight the importance of the Triassic tectono-magmatic belt for Mo exploration. In order to apply this metallogenic model to the whole Qinling orogen, further study is needed to compare the Wenquan deposit with other deposits. [Copyright &y& Elsevier]

Abstract: The Qinling–Dabie–Sulu orogen marks the junction between the North and South China Blocks. However, the exact timing of the final coalescence of the North and South China Blocks in the Qinling orogen is poorly constrained. This paper presents new SHRIMP zircon U–Pb chronology, major and trace elements, and Sr–Nd–Hf isotope data for five early Mesozoic granitic plutons across the Qinling orogen. SHRIMP zircon U–Pb dating shows that four plutons were emplaced in the Carnian (227–218Ma) of Late Triassic with a southward-younging trend and one pluton was emplaced in the Norian (∼211Ma) of Late Triassic. The Carnian plutons consist of high-K calc-alkaline granitoids (quartz monzodiorite, quartz monzonite, granodiorite and monzogranite) and calc-alkaline diorite. These rocks are mainly metaluminous and are characterized by high Sr and low Y and Yb contents, with high Sr/Y and La/Yb ratios, and by high Mg#, higher than pure crustal melts. The Norian pluton is composed of high-K calc-alkaline two-mica granites, which are peraluminous. These granites have low Sr and high Y and Yb contents and show similar Mg# to pure crustal melts. Detailed elemental and isotopic data suggest that the Carnian plutons were emplaced in a continental arc setting coupled with the northward subduction of the Paleo-Tethyan oceanic crust. Partial melting of subducted sediments triggered by dehydration of the underlying igneous oceanic crust, with subsequent melts interacting with the overlying mantle wedge, formed the high-K calc-alkaline granitic magmas. Partial melting of the hybridized peridotitic mantle wedge induced by slab melts generated the calc-alkaline dioritic magma. The Norian pluton was emplaced during continental collision between the South Qinling terrane and South China Block, which marks the final integration of the North and South China Blocks. Partial melting of subducted sediments at a shallow depth (<30km) in the collision (overthrust) zone could account for the origin of the Norian peraluminous granites. Our new data suggest that the final coalescence of the North and South China Blocks in the Qinling orogen is not synchronous with that in the Dabie–Sulu orogen, and thus, the Paleo-Tethyan oceanic basin between the North and South China Blocks most likely occurred as a ‘scissors-like’ shape, with closure in the Anisian (∼240Ma) of Middle Triassic in the eastern part (Dabie–Sulu) and in the Norian (∼211Ma) of Late Triassic in the western part (Qinling). [Copyright &y& Elsevier]

This study is the first attempt to understand the synergistic impact of anthropogenic and biogenic emissions on summertime ozone (O3) formation in the Guanzhong (GZ) Basin where Xi'an, the oldest and the most populous city (with a population of 9 million) in northwestern China, is located. Month-long (August 2011) WRF-Chem simulations with different sensitivity experiments were conducted and compared with near-surface measurements. Biogenic volatile organic compounds (VOCs) concentrations was characterized from six surface sites among the Qinling Mountains, and urban air composition was measured in Xi'an city at a tower 100ma.s. The WRF-Chem control experiment reasonably reproduced the magnitudes and variations of observed O3, VOCs, NOx, PM2.5, and meteorological parameters, with normalized mean biases for each parameter within -21 %. Subsequent analysis employed the factor separation approach (FSA) to quantitatively disentangle the pure and synergistic impacts of anthropogenic and/or biogenic sources on summertime O3 formation. The impact of anthropogenic sources alone was found to be dominant for O3 formation. Although anthropogenic particles reduced NO2 photolysis by up to 60 %, the anthropogenic sources contributed 19.1 ppb O3 formation on average for urban Xi'an. The abundant biogenic VOCs from the nearby forests promoted O3 formation in urban areas by interacting with the anthropogenic NOx . The calculated synergistic contribution (from both biogenic and anthropogenic sources) was up to 14.4 ppb in urban Xi'an, peaking in the afternoon. Our study reveals that the synergistic impact of individual source contributions to O3 formation should be considered in the formation of air pollution control strategies, especially for big cities in the vicinity of forests. [ABSTRACT FROM AUTHOR]

Porphyry Cu and Mo deposits are two economically important types of metal deposits worldwide, but factors controlling their difference remain enigmatic. Compared with the well-studied large porphyry Mo province in the south margin of the North China Block (S-NCB), the origin of newly discovered porphyry Cu deposits in the South Qinling (SQB) is poorly constrained. Integrated zircon LA-ICPMS U-Pb and molybdenite Re-Os ages and geological evidence indicate three stages of magmatism at Lengshuigou: (1) late Neoproterozoic (718 to 704 Ma) quartz diorite + albitite + granite association during the pre-ore stage, (2) 146 to 145 Ma granodiorite porphyry during the syn-ore stage, and (3) 145 Ma granite porphyry during the post-ore stage. Elemental and Sr-Nd isotopic evidence provide important constraints on their magma source. Pre-ore Neoproterozoic quartz diorite + albitite + granite was derived by re-melting of a mixture of crustal and juvenile mantle materials, and stronger fractional crystallization was involved in these ore-hosting intrusions than in contemporary granitoids hosted in the Douling Group. Syn-ore granodiorite porphyry was derived from mantle-derived magma with contributions from different proportions of crustal components. Post-ore granite porphyry was derived mainly from a crustal source. Nearly contemporaneous porphyry Cu and Mo systems were identified in Qinling Province, including the 147-139 Ma porphyry Mo systems in the S-NCB and 150-146 Ma porphyry Cu systems in the SQB. Granitic stocks related to porphyry Cu systems in the SQB are characterized by moderate SiO contents (58.01-69.07 %) and less radiogenic Nd-Hf isotopes (εNd = −3.8 to −6.3, εHf = −4.5 to +1.6), whereas the granitic stocks related to porphyry Mo deposits in the S-NCB have high SiO concentrations (64.00-76.00 %) and more radiogenic Nd-Hf isotopes (εNd = −18.0 to −11.6, εHf = −26.3 to −13.5). In addition, molybdenite from the Chigou and Lengshuigou porphyry Cu deposits in the S-NCB show higher Re contents (77.50-394.3 ppm) than those from nearly contemporaneous porphyry Mo deposits (9.34-49.7 ppm) in the S-NCB. These lines of evidence indicate that a higher proportion of mantle component was involved in the formation of porphyry Cu deposits in the SQB than nearly contemporaneous porphyry Mo deposits in the S-NCB. It is most likely that the nature of the magma source plays an essential role in the differences between porphyry Cu and Mo deposits. [ABSTRACT FROM AUTHOR]

At present, there is limited research on the effect of climate change on the growth of trees in the Qinling Mountains, and the effect of altitude has rarely been considered. In order to accurately grasp the impact of climatic factors on the natural forest in this region, the effect of water and temperature conditions on the radial growth of Pinus armandii was studied according to dendroclimatology principles. Response function and multivariate regression methods were applied to study the response of the tree-rings, including earlywood width and latewood width, of P. armandii at three elevations (1600-1800, 1800-2000, 2000-2200 m) to climate change in this region. The results showed that the radial growth of P. armandii at the three elevations contained rich climatic information. The tree-ring widths at the three elevations were significantly negatively correlated with September temperature of the previous year and May temperature of the current year (P < 0.05) and were also negatively correlated with August precipitation of the previous year and May precipitation of the current year. The late-wood width of P. armandii at 1600-1800 m and 1800-2000 m was less sensitive to temperature and precipitation than that of the earlywood. The latewood width of P. armandii at 2000-2200 m was significantly negatively correlated with December temperature of the previous year and May temperature of the current year (P < 0.01), and was significantly and positively correlated with August precipitation of the previous year (P < 0.05). Characteristic analysis of the special years showed that large quantities of precipitation in September and October of the previous year were more likely to result in the formation of a very wide tree-ring. High spring and summer temperatures and less precipitation from April to June more likely resulted in the formation of extremely narrow tree-rings. Therefore, high precipitation in autumn of the previous year was conducive to the growth of P. armandii, whereas high temperature and drought in spring and summer inhibited the growth of P. armandii. [ABSTRACT FROM AUTHOR]

It is generally accepted that leaf litter covers seeds, which may be beneficial for their survival, but it is unclear whether leaf litter contributes in different ways to the survival of plant seeds with contrasting sizes. In this study, we examined the effect of different levels of leaf litter coverage on seed predation and foraging/caching for small-seededPinus tabulaeformisand large-seededPinus armandiiin the Qinling Mountains, China. Our results showed that leaf litter failed to protectP. armandiiseeds from being removed by small rodents, whereas it improved seed survival forP. tabulaeformis.P. tabulaeformiswere eatenin situ, whereas moreP. armandiiseeds were eaten in the high leaf litter coverage plots. Therefore, we propose that leaf litter affects the survival and predation rates for large and smallPinusseeds in the Qinling Mountains, China. [ABSTRACT FROM PUBLISHER]

The North Dabashan thrust belt, which is located in South Qinling, is bounded by the Ankang fault on the north and the Chengkou–Fangxian fault on the south. The North Dabashan thrust belt experienced multiple stages of structural deformation that were controlled by three palaeostress fields. The first structural event (Middle Triassic) involved NNW–SSE shortening and resulted in the formation of numerous dextral strike-slip structures along the entire Chengkou–Fangxian fault zone and within the North Dabashan thrust belt, which suggests that the South China Block moved to the NW and was obliquely subducted under the North China Block. The second structural event (Late Triassic–Early Jurassic) involved NE–SW shortening that formed NW–SE-trending structures in the North Dabashan thrust belt. The third structural event (Late Jurassic–Early Cretaceous) involved ENE–WSW or nearly E–W shortening and resulted in additional thrusting of the North Dabashan thrust belt to the WSW and formation of the WSW-convex Chengkou–Fangxian fault zone, which has an oroclinal shape. Owing to the pinning of the Hannan massif and Shennongjia massif culminations, numerous sinistral strike-slip structures developed along the eastern Chengkou–Fangxian fault zone and were superimposed over the early dextral strike-slip structures. [ABSTRACT FROM AUTHOR]

The Jinlongshan gold deposit, Shaanxi Province, is a large Carlin-type deposit in the Western Qinling Gold Province (WQGP) in the Qinling Orogenic Belt, Central China. In this study, we present new EPMA and LA-ICP-MS geochemical data on the Fe-S-As minerals at Jinlongshan, which consist mainly of pyrite, arsenian pyrite and arsenopyrite. Diagenetic pyrite (Py0) is preferentially hosted in the sedimentary rocks as rounded or framboidal aggregates. Three types of hydrothermal pyrite (Py1, Py2 and Py3) and two types of arsenopyrite (Apy1 and Apy2) were newly identified in the ores and wall-rocks: fine-grained Py1 and Apy1 were formed at the early mineralization stage; coarse-grained Py2 and Apy2 were formed at the middle mineralization stage; and Py3 with stibnite were formed at the late mineralization stage. Their trace elements differ in concentrations, associations and rim-core zonations, implying different genesis and crystallization processes. Py0 is As-poor (Au < 0.105 wt% and As < 0.094 wt%); Py1 and Py2 are Au-As-rich (Au = 1.9-113 ppm and As up to 7.270 wt%); Py3 is Au-As-poor (Au = 0.03-11.4 ppm and As < 0.56 wt%); and Apy1 and Apy2 show the highest Au concentration (up to 576 ppm). Co, Ni and As (±Se and Te) occur in pyrite as isomorphism, and Ag, Cu, Pb and Zn are distributed primarily as invisible or visible sulphide inclusions. The dominant state of Au in the hydrothermal Fe-S-As minerals at Jinlongshan is lattice bound Au+1, and possibly invisible Au0 nanoparticles, whereas in the diagenetic Py0, the dominant state is mainly Au0. By integrating the evidence from ore deposit geology, mineral morphology, internal structure and trace element geochemistry of the Au-bearing Fe-S-As minerals, it is concluded that the formation of the Jinlongshan Au deposit may have been related to the regional metallogenic episode at around 170 Ma in the WQGP, which was coeval with the regional tectonic transition from a collisional compression to a late- to post-collisional extension in the Qinling Orogen. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Qinling Orogen in central China preserves the records of a complex geological and tectonic history, and also carries abundant mineral resources. Previous investigations on the Qinling Orogen have identified that the final transition from the Palaeo-Tethys Ocean to a continental orogen occurred in the Triassic, although the timing of the oceanic closure and the tectonic affinity of the Triassic Qinling belt have been poorly constrained. In this contribution, we compile the palaeomagnetic data and geological evidence related to sedimentation, magmatism and mineral systems. The palaeomagnetic data show that the Palaeo-Tethys Ocean in the Qinling Orogen gradually closed westward during the Triassic, terminating in the beginning of the Jurassic. Triassic strata are widely developed in the Qinling Orogen and conformably overlie the Permian strata. They are composed of carbonates and siliciclastic rocks that were strongly deformed and weakly metamorphosed during the Late Triassic to Late Jurassic. The Triassic magmatic rocks are dominated by I-type granitoids, with subordinate S-type and alkaline granites and minor carbonatite dykes, with a clear northward transition in lithology and geochemical features from the Mian-Lue Suture. Different types of Triassic mineral systems have been reported from this region, including sedimentary-hosted epizonogenic hydrothermal Hg-Sb, Pb-Zn ± Ag, Au deposits, metamorphic hydrothermal lodes of Au, Ag-Pb-Zn, Mo-Au and Mo, magmatic hydrothermal systems including porphyry Mo, breccia pipe Au, and carbonatite-hosted Mo deposits. We infer that the Triassic Qinling Orogen witnessed synchronous oceanic plate subduction in the west and continental linkage in the east, with a transition from oceanic basin to continental orogen through gradual subduction-related consumption of the oceanic plate. The Palaeo-Tethys Ocean closed in a westward scissor-like fashion in the Triassic and continental collision and extensive crustal shortening in the Jurassic, following which post-collisional extension occurred in the Early Cretaceous. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Neogene sediments of Gansu Group from northwestern China contain eolian and fluvial deposits. The origins of these sediments are very important for exploring the onset of Asian inland aridification, the pattern of paleo-atmospheric circulation, and the regional tectonics and geomorphic evolution during the Miocene. Here we present detrital-zircon age spectra of typical eolian and fluvial deposits from highlands and subsidence basin, and compare them with those of surrounding eroded mountain (such as the West Qinling Mountains and Liupan Mountains) materials and Quaternary loess derived from the Asian inlands. The results reveal that (1) the detrital-zircon age spectrum of the Miocene eolian sample is remarkably different from the eroded materials of the West Qinling Mountains and the Miocene fluvial deposits from Tianshui region, but very similar to the Quaternary loess deposits. This indicates that the provenance of Miocene eolian sediments is similar with the Quaternary loess, and thus further confirms the previous conclusions that the distribution of Asian arid lands and the pattern of atmospheric circulation during the Miocene are broadly similar with the Quaternary. (2) The detrital-zircon age spectrum of the fluvial deposits (with age about 11.5 Ma) from Tianshui region is different from the eroded materials of West Qinling Mountains, but similar with that of the Liupan Mountains to the east, which may suggest that the Liupan Mountains have already been exhumed by 11.5 Ma. [ABSTRACT FROM AUTHOR]

Natural seedling regeneration and tree establishment are affected by various environmental factors. In this study, we established eight, eight, six, and four independent forest stands (each stand was further divided into five subplots) respectively based on the altitudinal gradient, stand density, slope location, and slope aspect to investigate the effects of environmental factors on tree seedling regeneration in a pine-oak mixed forest. The results indicated that the seedling density was significantly higher at altitudes of 1,283 m to 1,665 m, whereas the sapling density did not differ with altitudes. The seedling and sapling density decreased significantly at 1,835 m. The seedling densities on the upper slopes were much higher than those on the middle and lower slopes, whereas the sapling density had no difference. The sapling density decreased gradually from the southwest (20°-75°) whereas it increased on the shady slopes to the northeast (40°). The seedling density increased from southwest (20°) to northeast (40°). The seedling and sapling densities increased with the stand density (850 trees ha to 1,525 trees ha) whereas the sapling density was significantly lower in stands (1,900 trees ha). Principal components analysis showed that the slope aspect and stand density had more important roles in tree regeneration in this study region compared with the other two factors. Therefore, our findings suggest that it will be beneficial to keep stands at a moderate density on shady slopes. Appropriate thinning of higher density stands is also expected to promote the natural regeneration of pine-oak mixed forest. [ABSTRACT FROM AUTHOR]

To contribute to a better understanding of the regeneration strategy of Betula albosinensis forests and the likely reasons behind either the successful recovery or failure after strip clearcutting, we compared the population structures and spatial patterns of B. albosinensis in eight B. albosinensis stands in Qinling Mountains, China. Four cut and four uncut stands were selected, and each sampled using a single large plot (0.25 ha). Results indicated that, on the one hand, B. albosinensis recruitment was scarce (average of 48 stems ha−1) in the uncut stands, relative to the mature population (average of 259 stems ha−1), suggesting a failure of recruitment. On the other hand, the subsequent regeneration approximately 50 years after the strip clearcutting showed that the density of the target species seedlings and saplings has increased significantly, and the current average density of seedlings and saplings was 156 stems ha−1. The clumped spatial pattern of B. albosinensis suggested that their regeneration was highly dependent on canopy disturbance. However, recruitment remained poor in the uncut stands because most gaps were small in scale. The successful regeneration of sunlight-loving B. albosinensis after strip clearcutting was attributed to the exposed land and availability of more sunlight. Bamboo density did not influence B. albosinensis recruitment in the uncut stands. However, stand regeneration was impeded after strip clearcutting; thus, removing bamboo is essential in improving the competitive status of B. albosinensis at the later stage of forest regeneration after clearcutting. The moderate severity of disturbance resulting from strip clearcutting reversed the degeneration trend of primary B. albosinensis stands. This outcome can help strike a balance between forest conservation and the demand for wood products by releasing space and exposing the forested land for recruitment. Life history traits and spatiotemporal disturbance magnitude are important factors to consider in implementing effective B. albosinensis regeneration strategies. [ABSTRACT FROM AUTHOR]

Cyclospora spp. have been identified as one of the most important intestinal pathogens causing protracted diarrhea in animals and human beings. To determine the Cyclospora species in the non-human primate Rhinopithecus roxellanae, a total of 71 fecal samples from 19 endangered snub-nosed monkeys in Shaanxi province were collected and examined using Sheater’s sugar flotation technique and by sequencing the fragments of 18S rDNA. Only two Cyclospora isolates from 2 golden snub-nosed monkeys (R. roxellanae) were obtained and identified between July 2011 and August of 2012. The sequences of the 18S rDNA for the two Cyclospora isolates were 477 bp, with no nucleotide variation between them. Phylogenetic analysis based on the 18S rDNA sequences revealed that the two Cyclospora isolates were posited into the clade Cyclospora spp. and sistered to C. colobi. These results first showed that Cyclospora infection occurred in R. roxellanae in hot and rainy weather, which would provide useful information for further understanding the molecular epidemiology of Cyclospora spp. and the control of Cyclospora infection in non-human primates as well as in human beings. [ABSTRACT FROM AUTHOR]

A total of 290 tree-ring samples, collected from six sites in the West Qinling Mountains of China, were used to develop six new standard tree-ring chronologies. In addition, 73 proxy records were assembled in collaboration with Chinese and international scholars, from 27 publically available proxy records and 40 tree-ring chronologies that are not available in public datasets. These records were used to reconstruct annual mean temperature variability in the West Qinling Mountains over the past 500 years (AD 1500–1995), using a modified point-by-point regression (hybrid PPR) method. The results demonstrate that the hybrid PPR method successfully integrates the temperature signals from different types of proxies, and that the method preserves a high degree of low-frequency variability. The reconstruction shows greater temperature variability in the West Qinling Mountains than has been found in previous studies. Our temperature reconstruction for this region shows: 1) five distinct cold periods, at approximately AD 1520–1535, AD 1560–1575, AD 1610–1620, AD 1850–1875 and AD 1965–1985, and four warm periods, at approximately AD 1645–1660, AD 1705–1725, AD 1785–1795 and AD 1920–1945; 2) that in this region, the 20th century was not the warmest period of the past 500 years; and 3) that a dominant and persistent oscillation of ca. 64 years is significantly identified in the 1640–1790 period. [ABSTRACT FROM AUTHOR]

The east-west trending Tsinling Mountains in central China were uplifted at the end of the Middle Jurassic [176-161 million years ago (Ma)] in Yanshanian, thus effectively and geographically defining the northern climate as cold and dry, and the southern climate as warm and humid. Influenced by paleoenvironmental variation, the karst process shows differences between northern and southern China. Using the systems approach, the authors integrated the geologic history, climate, and hydrological conditions to analyze the causes of the karst differences in northern and southern China, as well as in the Tibetan Plateau. Carbonate rock deposition began in the Mesoproterozoic Era (1,600-1,000 Ma) in north China, and in the Sinian Sub-Era (825-570 Ma) in south China. In north China, the rock formation ended in the Mid-Ordovician (466 Ma), while in South China the deposition continued to the Triassic (250-200 Ma). Tibetan Plateau was deposited in the Late Permian (257-250 Ma). The different depositional environment caused different lithologies: the limestones are largely micritic in the north, but are massive and sparry in the south. The modern karst features were formed mainly in the Tertiary (53-2.6 Ma) and the Quaternary. In the Quaternary, the Tibetan Plateau arose sharply, which formed the monsoon system of East Asia, and loess started to deposit in north China, which partly delayed or prevented karstification in north China, and differentiated the karst features from those in south China. Thus, the karst process in north China is mainly hypogene, while the south is epigene in the Quaternary. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate knowledge and use of wild food plants and fungi in Han (i.e. Chinese) nationality villages in central China, including famine plants used in the respondents' childhood. A valley adjacent to the extremely species-rich temperate forest vegetation of the Taibai Nature Reserve was chosen. Eighty-two people from 5 villages took part in the study. Altogether, 159 wild food plant species and 13 fungi folk taxa were mentioned by informants. The mean number of freelisted wild foods was very high (24.8; median - 21.5). An average respondent listed many species of wild vegetables (mean - 17, median - 14.5), a few wild fruits (mean - 5.9 and median - 6) and very few fungi (mean - 1.9, median - 1), which they had eaten. Over 50% of respondents mentioned gathering the young shoots or leaves of Celastrus orbiculatus, Staphylea bumalda and S. holocapra, Caryopteris divaricata, Helwingia japonica, Pteridium aquilinum, Pimpinella sp., Amaranthus spp., Matteucia stru-thiopteris, Allium spp., Cardamine macrophylla and Chenopodium album. Only one species of fruits (Schisandra sphenanthera) and none of the mushrooms were mentioned by over half of the respondents. Although very diverse, it can be noted that the use of wild vegetables has decreased compared to the second half of the 20th century, as informants listed several plants which they had stopped using (e.g. Abelia engleriana) due to the availability of cultivated vegetables and other foodstuffs. On the other hand, the collection of the most well-known wild vegetables is maintained by selling them to tourists visiting agritourist farms, and restaurants. [ABSTRACT FROM AUTHOR]

The Liziyuan gold deposit, located on the northern margin of the western Qinling orogen (WQO), consists of five mineralized sites hosted by metavolcanic rocks, and one hosted by the Tianzishan monzogranite. Orebodies mainly occur as lenticular veins along NW-striking dextral ductile strike–slip shear zones. Major wall rock alteration includes silicification, pyritization, and carbonation, progressively increasing in intensity towards the orebodies. Ore minerals are dominated by pyrite, galena, and chalcopyrite; the major gangue minerals are quartz and calcite. Native gold is present chiefly as separate phases in sulphide and quartz microfractures. We recognize four stages of mineralization: (I) pyrite-quartz, (II) native gold-chalcopyrite-pyrite-quartz, (III) pyrite-freibergite-galena-quartz-carbonate, and (IV) carbonate stages. Fluid inclusion petrography and microthermometric results suggest that three types of primary fluid inclusions (carbonic, CO2–H2O, and aqueous) are present in the deposit. Microthermometric data and Laser Raman analyses indicate that the ores were deposited from moderate temperature (240–280°C), low salinity (0.5–9.1 wt.% NaCl equiv.) H2O–NaCl–CO2–(CH4) fluids. The common coexistence of aqueous, CO2–H2O, and carbonic inclusions indicates the trapping of heterogeneous immiscible fluids. Trace elements in mineralized quartz and carbonate veins suggest that the ore-forming fluids were mainly produced by prograde metamorphism of the upper crust. The calculated and δD values are 1.8–3.8‰ and –77‰ to –75‰, respectively, for quartz from stage II and –8.5‰ to –6.6‰ and –72‰ to –71‰ for calcite from stage III, implying that the ore-forming fluids were metamorphic in origin and evolved by late-stage mixing with meteoric water. Pyrite and galena have δ34S values of 3.9–8.5‰ with a pronounced mode at 5–8‰. Such relatively homogeneous sulphur isotopic compositions are consistent with orogenic gold deposits throughout the world, indicating that the sulphur was mainly sourced from reduced metamorphic fluids. The Liziyuan gold deposit can be grouped with other orogenic gold deposits that have similar characteristics. Geological observations and available isotopic ages suggest that the Liziyuan lode mineralization was related to the Indosinian orogenesis of the Qinling belt. Triassic continental collision caused crustal thickening, dextral ductile shearing, and greenschist facies metamorphism throughout the orogen. Due to the intensive deformation and metamorphism, crustal rocks released copious fluids that evidently mobilized and extracted ore elements along their flow pathways. The ductile shear zone in the Liziyuan mining area provided regions of low mean stress and high permeability, and thus appeared to be preferential channels for precipitation of the ore-forming fluids. As highly charged fluids migrated into the high permeability shear zones, rapid changes in physicochemical conditions resulted in sulphide precipitation and gold mineralization. [ABSTRACT FROM PUBLISHER]

Studies of spatial proximity between individuals are important for an understanding of social structure because animals are more likely to interact with individuals in close spatial proximity. Here, we apply social network analysis to proximity data collected between 2001 and 2003 from an individually identified, provisioned, free-ranging band of Sichuan snub-nosed monkeys ( Rhinopithecus roxellana) in the Qinling Mountains, central China. We aimed to quantify the social network structure and to gain insight into each individual's position within the social network. The overall network connectivity of the study band was sparse, with a low group density of 0.17. We identified nine one-male-multifemale units (OMUs) in the study band using hierarchical cluster analysis, which confirms that this species forms a multilevel society in its natural habitat. Based on sex differences in eigenvector and betweenness centralities, adult females have more important social roles than males. Among females, lactating females scored higher betweenness and eigenvector centralities than other females. However, our results do not suggest the existence of key individual(s) in the social network of the study band. The global clustering coefficient characteristic of the band was 0.3 ± 0.1, with little variation between individuals, suggesting that the removal or death of any specific individual would not significantly disrupt its general network structure. Our results also show that proximity commonly occurs among unit members, but can also occur between females of different OMUs. These observations suggest that snub-nosed monkeys have a loose-knit or fluid rather than a rigid female-bonded social system, which may be a common trend for species living in multilevel societies. [ABSTRACT FROM AUTHOR]

Igneous rock textures reflect the cooling history of the parental magma. Combined with chemical data, they can provide physical and chemical information about the evolution of a magma body. The petrographic textures and chemical compositions of 21 coarse- and fine-grained granite samples along an ∼250 m horizontal outcrop of the Shanggusi granite porphyry are presented in this case study. The coarse-grained granite porphyry is an early intrusion, and the fine-grained granite dykes, mostly intruded into the granite porphyry, are later intrusions. The studied samples have nearly homogeneous major element bulk-rock and mineral compositions, but show large variations in their trace element compositions and textural characteristics. The trace element data suggest the influence of hydrous fluids (possibly enriched in CO2, F, and Cl) in the evolution of the plutonic body. Textural analysis of the coarse-grained granite porphyry indicates that the crystal size distribution (CSD) slopes, intercepts and total numbers of groundmass decrease from the center to the margin of the intrusion in contrast to the maximum diameter of the crystals (Lmax) (average length of the four largest quartz crystals for each sample); however, most fine-grained samples and the groundmass of the coarse-grained samples show concave-down CSDs, indicating textural coarsening. Quartz CSDs in the coarse-grained samples are kinked, with a steep-sloped log–linear section representing small crystals (<1 mm) and a shallow-sloped log–linear section representing large crystals (>1 mm). These two crystal populations are interpreted as resulting from a shift in cooling regime. The straight CSDs of two fine-grained samples may be due to a different cooling history. In general, the spatial variation of the CSD patterns can be attributed to various degrees of overgrowth and mechanical compaction. The quartz phenocrysts in several coarse-grained samples exhibit a high degree of alignment, which may be the result of magmatic flow. By integrating the field geology, geochemistry and quantitative textural data from the horizontal profile of the Shanggusi granite porphyry, it is suggested that hydrous fluids at the top of the intrusion not only controlled the fractionation of elements but also affected its cooling history. Fluid migration-controlled undercooling can explain the solidification processes in the Shanggusi intrusion, and may also be prevalent in other fluid-rich shallow intrusions. Quantitative integration of textural and geochemical data for igneous rocks can contribute to our understanding of the relationships between physical and chemical processes in a magma system, and provide relatively comprehensive insights into the petrogenesis of granites. [ABSTRACT FROM AUTHOR]

The Western Qinling orogenic belt marks the northeastern margin of the Tibetan Plateau. Its late Cenozoic orogenic history is recorded in an excellent sedimentary sequence exposed in the Tianshui sub-basin of the Longzhong basin. According to the magnetostratigraphic analysis from the Yaodian and Lamashan sections, we speculate that the late Cenozoic Tianshui basin accumulated lacustrine/floodplain deposits from ~14.8 to ~2.6 Ma. In addition, detrital apatite fission-track thermochronologic and paleocurrent data reveal that the detritus of the Tianshui basin mostly derived from the Western Qinling and that the youngest population age represents a ~14 Ma volcanic intrusion, which can be related to the lithospheric deformation and uplift of the Tibetan Plateau. Furthermore, two stages of variations in depositional facies and average accumulation rates were attributed to the pulse uplift and deformation of the Western Qinling at 9.2-7.4 and ~3.6 Ma. [ABSTRACT FROM AUTHOR]

Major and trace element compositions of constituent minerals, partly decomposed rims of orthopyroxenes (DRO), 'closed' melt pockets (CMP) and open melt pockets (OMP) in some Western Qinling peridotite xenoliths were obtained by LA-ICP-MS. Systematic core-to-rim compositional variations of garnet, clinopyroxene and orthopyroxene demonstrate that these minerals underwent variable degrees of subsolidus breakdown or partial melting. Both DROs and CMPs consist of similar mineral assemblages and are characterized by high TiO, CaO + NaO and low MgO contents; they are enriched in LREE and LILE compositions, have positive anomalies in Pb, Sr and particularly Ti, negative Th and U, and variable Zr and Hf anomalies. These chemical features are distinct and reflect reactions involving the orthopyroxenes. Compared to the CMPs, the OMPs, which are composed of a complex assemblage of minerals, display lower FeO and MgO contents, larger ranges in SiO and NaO, higher TiO, AlO, CaO and trace element concentrations, slightly negative Zr and Hf anomalies, and apparently negative Ti anomalies. Modeling calculations of partial fusion of orthopyroxenes and clinopyroxenes suggest that the CMPs most likely originated from the breakdown of orthopyroxenes with variably minor contribution of external melts from the melting of clinopyroxenes, whereas the OMPs were probably formed from the modification of the CMPs through the interaction with large amount of external melts. [ABSTRACT FROM AUTHOR]

The paleosol samples from the fifth layer of the loess profile at Renjiapo in the eastern suburb of Xi'an are observed and analyzed using electron microscope and energy spectrum. Minerals such as AgSO and molybdenum, which are rare to find and can indicate typical dry climate environment, are found in this layer of paleosol. Secondary mineral is usually granular form of ellipsoidal and crystallization, and has the characteristics of chemical precipitating crystallization of apertures and fracture. Molybdenum minerals have the characteristics of colloidal substances. There are two kinds of secondary minerals. One is silver sulfate mineral and the other is silver oxide mineral. The movement of secondary silver, molybdenum and cobalt minerals, new clay mineral, FeO and AlO indicates that S has experienced strong chemical weathering and mineral dissolution during its development. Silver, molybdenum, and cobalt can be released from primary minerals. During that period, the precipitation was abundant in Xi'an where soil reached an acidity stage of chemical weathering. At the later development stage of paleosol in the lowest part of S, warm and wet monsoon climate had changed to dry and non-monsoon climate. In the period of the formation of AgSO, which is easier to dissolve than CaSO, a dry and non-monsoon climate was present in the Guanzhong Plain. Strong evaporation resulted in the accumulation of SO in the soil water solution and the formation of AgSO. At that time, summer monsoon of East Asia was weak and did not cross Qinling Mountains to reach Guanzhong Plain. And at that time, the precipitation in Xi'an was less than 300 mm, and it was drier then in Xi'an than at present in Lanzhou. [ABSTRACT FROM AUTHOR]

Field investigation and laboratory research on flysch of the Liufengguan Group in Qinling indicate the following: (1) Sandstone of the Liufengguan Group is categorized as feldspathic lithic graywacke with a minor amount of lithic graywacke in the QFR triangular diagram. Grain size ≤0.3 mm. Bedding plane structures such as groove casts and suspected flute casts can be found at the bottom of the sandstone. It is inferred that currents may have come from the southeast during deposition. Bedding structures such as ripple marks, graded bedding, parallel bedding, small-scale cross bedding, climbing bedding, suspected convolute bedding, microlamination and sliding structures have also been observed, which are of indicative significance. It is thought that the Liufengguan Group has the sedimentary characteristics of bedding, bedding plane structures and lithological assemblages of deep-sea low-density turbidity current deposits. The vertical succession of the Bouma sequence in the inner fan subfacies zone is generally incomplete: the assemblage of Ta and Tabc is commonly seen; the succession of the middle fan subfacies zone is relatively complete; and divisions Te and Tb are common in the outer fan subfacies zone. (2) The flysh of the Liufengguan Group is a sequence of deep-sea argillaceous-arenaceous submarine fan deposits, in which the authors recognize the inner, middle and outer fan subfacies and also nine types of lithofacies: normal graded sandstone (A1), medium- to thick-bedded, fine-grained sandstone (A2), medium- to thick-bedded and massive siltstone (A3), thin-bedded, fine-grained sandstone and mudstone (B1), irregular interbeds of thin-bedded, fine-grained sandstone and siltstone (B2), thin-bedded, fine-grained sandstone (C1), very thin-bedded, fine-grained sandstone (D1), olistostromes (E1) and deep-sea mudstone (F). The inner fan consists of four microfacies: natural levee (A1), water channel (A2, A3) and olistostromc (E1); in the middle fan there also occur four microfacies, i.e., branch channel (B1), branch channel (B2), interdistributary bay (D1) and olistostrome. The outer fan is made up of the branch channel (C1) and sheet sand (D1) microfacies, which alternate vertically with sediments of deep-sea plain subfacies (F). There occur fining- and thin ning-upward channel deposits in the outer-fan subfacies zone of the submarine fan of the Liufengguan Group observed in this study. The quartz content of the graywacke of the deposits is all higher than 40% and may reach as high as 60%. Therefore, on the basis of the aforementioned features, this flysh should be formed in a passive continental-margin tectonic environment. [ABSTRACT FROM AUTHOR]

Mesozoic granitoids are widespread in the Qinling-Dabie-Sulu orogenic belt. Precise U-Pb dating on these granitoids can reveal the evolution of the continental collision orogen and thus provide information on the nature of magma sources. This study presents zircon LA-ICP-MS U-Pb dating and whole-rock geochemical analyses for two intrusions at Changba and Huangzhuguan in western Qinling. Zircon U-Pb ages for central and marginal phases of the Huangzhuguang intrusion are 214±1 Ma and 213±3 Ma, respectively. Zircons from the Changba intrusion yield a dominant cluster with an U-Pb age of 213±2 Ma. Collectively, these ages are younger than ages of 220 to 240 Ma for ultrahigh-pressure metamorphism due to the continental collision between the South China Block and the North China Block, corresponding to syn-exhumation magmatism. Some inherited zircons occur in the Changba intrusion, yielding a weighted mean of 206Pb/238U ages at 757±14 Ma. This indicates that the Changba intrusion has the crustal source of mid-Neoproterozoic ages and a tectonic affinity to the South China Block. Geochemically, the two intrusuons are both rich in LILE and LREE but depleted in HFSE and HREE, similar to arc-type igneous rocks. The Huangzhuguang intrusion exhibits linear correlations between SiO2 and the other major oxides, implying chemical evolution from a cognate magma source. It contains mafic enclaves, suggesting possible mixing of felsic-mafic magmas. The Changba granite is rich in Si and K but poor in Fe and Mg as well as has a high value of Fe*, suggesting strong differentiation of granitic magma. Therefore, the two intrusions were derived from the Late Triassic anatexis of the continental crust of different compositions in the northern margin of South China Block. This process may be coupled with exhumation of the subducted continental crust in the stage of late collision. [ABSTRACT FROM AUTHOR]

U-Pb dating was made by the LA-ICP-MS method for detrital zircons from the Wudangshan volcanic-sedimentary succession in the South Qinling. Samples comprise quartz sandstones of the Wudangshan Group collected from the base of the Yangping Formation and an upper layer of the Shuangtai Formation overlain its volcanic sequence, and two river-sand collections from the drainage systems cutting across the two formations, respectively. The results show that the Yangping detrital zircons are dominated by 830--780 Ma grains with a minor population of ~1.0--0.84 Ga and sporadic grains of ~2.6, ~2.4 and 2.0 Ga, whereas the Shuangtai zircons yield an upper intercept age of 763±33 Ma, identical to the timing of the Wudangshan volcanism within error, with few concordant grains of 1.9 and 0.86 Ga. Age spectra for the two river-sand samples are similar to those of the Yangping and Shuangtai Formations, respectively. It thus suggests that the Wudangshan strata are less than 780 Ma, whereas their major detrital zircon populations of 1.0--0.85 Ga and 830--780 Ma are consistent with timing of the Hannan magmatic activities along the northwestern margin of the South China Block. This suggests a Hannan or adjacent area provenance for the Wudangshan strata. The Wudang area is characterized by rift-related igneous events at ~755 and ~680 Ma, respectively, pointing to a tectonomagmatic history different from the Hannan area. It is inferred that the ~755 Ma magmatism is likely to indicate a separation of the South China Block from the supercontinent Rodinia, while the ~680 Ma event suggests a further split between the South Qinling and some unknown continent. [ABSTRACT FROM AUTHOR]

For group-living primates, the information on postconflict management is crucial for understanding primate competition and cooperation. However, such information is poorly known for snub-nosed monkeys, especially for wild populations. In this study, from September 2007 to June 2008, we investigated postconflict behavior among adult females Sichuan snub-nosed monkeys Rhinopithecus roxellana within one-male units in a wild, provisioned group in the Qinling Mountains of China by means of the time-rule method and the PC-MC method. We obtained a total of 81 PC-MC pairs and each individual was involved in only 0.004 aggressive behavior per observation hour. The first affiliative behavior was more likely to occur within the first minute after a conflict. The postconflict affiliative behaviors most often seen were contact-sit, embrace and grooming. The affiliative contacts between adult females occur due to selective attraction, i.e. reconciliation. The pattern of postconflict affiliation demonstrates that the R. roxellana belongs to a tolerant species [Current Zoology 56 (2): 222-226, 2010]. [ABSTRACT FROM AUTHOR]

The Wulong pluton was emplaced in the metamorphic complex of the Mesoproterozoic Foping Group, South Qinling. A few mafic enclaves which are rounded in shape with sharp boundaries with the host granites in the southern part of the pluton. Based on petrography, geochemistry and chronology data, it is indicated that the Wulong pluton shows some adakitic affinities with depletion in HREE (Yb=0.33–0.96 µg/g, Y=4.77–11.2 µg/g); enrichment in Sr (643–1115 µg/g) and Ba (775–1386 µg/g), high Sr/Y ratios (57.3–160) and Y/Yb ratios (11.0–14.3), and slightly negative Eu anomaly (δEu=0.70–0.83). These patterns suggest a feldspar-poor and garnet±amohibole-rich fractionation mineral assemblage. The mafic enclaves have high concentrations of Mg (MgO=4.15%–8.13%), Cr (14.8–371 µg/g), and Ni (20.0–224 µg/g), and high Nb/Ta ratios (15.42–21.9). It seems that the underplating mantle magma was responsible for the generation of the mafic magma. Companied with the results of investigations for the Qinling Orogenic Belt, it was found that partial melting of the thickened lower crust, which was triggered by the underplated mantle-derived magmas, had generated the felsic magma. The Wulong pluton provided evidence for a mixing and mingling process of two kinds of mamma. Its formation probably represents the oceanic slab breakoff during the late orogenic stage in the Qinling area. [ABSTRACT FROM AUTHOR]

New 40Ar/39Ar ages are presented from the giant Sulu ultrahigh-pressure (UHP) terrane and surrounding areas. Combined with U-Pb ages, Sm-Nd ages, Rb-Sr ages, inclusion relationships, and geological relationships, they help define the orogenic events before, during and after the Triassic collision between the Sino–Korean and Yangtze Cratons. In the Qinling microcontinent, tectonism occurred between 2.0 and 1.4 Ga. The UHP metamorphism occurred in the Yangtze Craton between 240 and 222 Ma; its thermal effect on the Qinling microcontinent was limited to partial resetting of K-feldspar 40Ar/39Ar ages. Subsequent unroofing at rates of 5–25 km Myr−1 brought the UHP terrane to crustal levels where it underwent a relatively short amphibolite facies metamorphism. The end of that metamorphism is marked by 40Ar/39Ar ages in the 219–210 Ma range, implying cooling at crustal depths at rates of 50–200 °C Myr−1. Ages in the 210–170 Ma range may reflect protracted cooling or partial resetting by Jurassic or Cretaceous magmatism. Jurassic 166–149 Ma plutonism was followed by cooling at rates of c. 15 °C Myr−1, suggesting relatively deep crustal conditions, whereas Cretaceous 129–118 Ma plutonism was succeeded by cooling at rates of c. 50 C Myr−1, suggesting relatively shallow crustal depths. [ABSTRACT FROM AUTHOR]

Two springs (Cuihua Spring, Shuiqiuchi Spring) in Cuihua Mountain of the Qinling Mountains were observed and sampled monthly during 2004 and 2005 to trace their physical properties and chemical compositions with seasons. Although both pH values and cation (Ca2+, Mg2+, K+, and Na+) contents of Cuihua Spring are higher than those of Shuiqiuchi Spring, seasonal variations in both springs are obvious. The pH values of both spring waters are between 5.69 and 6.98, lower than that of rainwater during summer and autumn. From January to November, the pH values of both springs similarly vary from high to low and then to high again. Variations in electric conductivities of two spring waters are contrary, although their electric conductivities are positively correlative with the cation content respectively. This can be attributed to different water sources of the two springs or different acidic rocks they passed. The contents of HCO3 –, Ca2+, Mg2+, K+ are low, indicating a low silicate weathering that the strata in this district are mainly composed of granite and schist of quartz and mica. Differing from change in spring water in karst regions of South China where abundant precipitation and dilution of rainwater cause low pH and electric conductivity in summer and autumn, the seasonal variations in the pH values and the electric conductivities of two springs in Qinling Mountains are attributed to seasonal changes in CO+ are low, indicating a low silicate weathering that the strata in this district are mainly composed of granite and schist of quartz and mica. Differing from change in spring water in karst regions of South China where abundant precipitation and dilution of rainwater cause low pH and electric conductivity in summer and autumn, the seasonal variations in the pH values and the electric conductivities of two springs in Qinling Mountains are attributed to seasonal changes in CO2 produced by microorganisms' activity in soil within respective year, rather than rainfall. The microorganisms' activity in soil produces more CO2 during summer and autumn. Therefore, the water nature of springs in silicate regions chiefly reflects the seasonal changes of CO2 produced by the microorganisms in soil. [ABSTRACT FROM AUTHOR]

A simple topographic correction approach, the Variable Empirical Coefficient Algorithm (VECA), was developed using theoretical and statistic analyses of the radiance values of remotely sensed data acquired for rugged terrain and the cosine of the solar illumination angle (cos i). Visual comparison and statistical analysis were used for evaluation of the proposed algorithm and the performance of the VECA approach was compared with 10 commonly used methods. The test site selected for this study is located on the south hill of the Qinling Mountain in Shanxi province, China, and the remotely sensed data used were from Landsat-7 Enhanced Thematic Mapper Plus (ETM+) images. The results indicate that the Cosine-T, Cosine-C, sun-canopy-senor (SCS) and Cosine-b correction have the problem of overcorrection, and the other corrections can be classed into three ranks: the VECA, b correction and C models performed the best, followed by the Teillet-regression correction model, and the SCS+C, Minnaert and Minnaert-SCS corrections performed the worst. The proposed VECA correction and the b correction are the most capable of removing the topographic effects of the ETM+ image. The VECA is not only simple in theory but also easy to operate, indicating that the VECA is an effective topographic correction tool in remote sensing techniques. [ABSTRACT FROM AUTHOR]

The Qinling Mountain range constitutes a critical boundary for climate and vegetation distribution in eastern central mainland China owing to its importance as a geographic demarcation line. In this article, cores from 88 Chinese pines ( Pinus tabulaeformis) from the southern (MW site) and northern (NWT site) slopes of the Qinling Mountains were used to reconstruct seasonal temperature variations. During the calibration period, significant correlations were found between ring width and the mean temperature from prior September to current April of 0.76 at the southern slope, and between ring width and the mean May–July temperature of 0.67 at the northern slope. The subsequent temperature reconstructions span 1760–2005 for the northern site and 1837–2006 for the southern site. Prior to the mid-20th century, low September–April temperatures were, in general, followed by high May–July temperatures, probably reflecting variations in the winter and summer monsoon. However, since the mid-20th century, both records show trends of a more pronounced increase in September–April temperature on the southern slope. The results provide independent support for the interpretation that recent warming is unusual in nature, coinciding with the observed record. The results compare well with tree-ring based reconstructions from the surrounding regions, suggesting regional signals in the Qinling Mountain reconstructions. [ABSTRACT FROM AUTHOR]

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40Ar/39Ar ages were determined for 6 phlogopite samples from a kamafugite pipe occurring in western Qinling, yielding a time span of 22 to 23 Ma for kamafugite eruption. Together with known geochronological data for the Qinghai-Tibet Plateau (QTP) and its peripheral regions, it is concluded that these Cenozoic potassic-ultrapotassic volcanic rocks are products of post-collisional volcanism. The age of the Cenozoic volcanic rocks in western Qinling partly overlaps that of potassic volcanics from the Gandise belt, reflecting the northward migration of the post-collisional volcanism in QTP. The age data not only confirm the temporal and spatial migration of post-collisional volcanism in QTP, but also provide geochronological constraints on the geodynamic setting at depth and the regimes of the tectonic evolution since Neogene in western Qinling regions. [ABSTRACT FROM AUTHOR]

Focuses on a study on the strontium (Sr) and lead (Pb) isotopic constraints on ore formation of the copper deposits in the Bikou-Group rocks in Qinling, China. Constraints of Sr isotope on superimposed mineralization and its age; Constraints of Pb isotopic compositions on ore source and age of the volcanic rocks of Bikou-Group; Conclusion.

The article discusses the chemical constituents of a stem bark from a periploca sepium collected in Qinling Mountain, China. The bark, which contains many kinds of compounds including cardenoides and pregnane glycosides, has been applied in traditional Chinese herbal medicine for more than two thousand years.