Dulan County Research Articles

A study based on high-density data examines the current status and evolution laws of heavy metal environmental capacity in the Bardawu area of the Qinghai-Tibet Plateau

As the first ladder of China, the Qinghai-Tibet Plateau has always been known as the “roof of the world”. Its environmental carrying capacity can be estimated more accurately than other regions because of its harsh natural environment, low population density, limited industrial and agricultural development, and low human activities. However, the current ecological risks of Co and threshold research are limited, and there is a lack of awareness of W’s environmental risks. Hence, this study assessed the ecological support potential of the Bardawu region within Dulan County, Qinghai Province, using 7373 soil specimens, determined regional soil baseline measures, and applied the substance equilibrium linear technique along with the ecological aggregate indicator technique to examine the heavy metal content of the soil. A comprehensive evaluation of the environmental capacity and health risks was conducted to provide a reference for pastoral planning. The findings indicated that the cumulative static ecological capacity of the six trace heavy elements in the soil was ranked as follows: Cr > Li > Ni > Cu > W > Co, with W and Co positioned as the final pair. The remaining areas with a high environmental capacity were predominantly found in the study zone. The central sector exhibited diminished environmental capacity in the southwest and northeast and presented a contamination hazard. Land use, soil type, and geological type considerably affected the six elements in the study area at the p < 0.05. The Bardawu region’s mean comprehensive index of soil environmental capacity was 0.98, indicating an intermediate level of environmental capacity and a moderate health risk. This study focuses on the geological context and influence of pastoral activities on the soil, augments the distribution of various elements across the Tibetan Plateau, and suggests preliminary soil governance strategies. The findings of this study lay the groundwork for soil environmental conservation and remediation efforts in highland regions.

Overview of the Archaeological History of Hot Water Tombs in Dulan County, Qinghai Province

Overview of the Archaeological History of Hot Water Tombs in Dulan County, Qinghai Province

The excavation of the 2018 Xuewei tomb No. 1 in Reshui cemetery, Dulan County, Qinghai

Abstract After a looting case was cracked on March 15, 2018, the Institute of Archaeology of the Chinese Academy of Social Sciences and other organizations promptly conducted a rescue excavation of the looted tomb No. 1 at Xuewei. The tomb is the mausoleum of the king of Touyu-houen under Tubo’s rule in the mid-eighth century CE. It consists of two parts: the tomb compound aboveground and the underground structure. The former includes enclosure walls, sacrificial buildings, a mound, and a cloister. The latter consists of the entry ramp, the tomb pit, the screen wall, the tomb corridor, and the tomb chambers comprised of a main chamber and four side chambers, which is consistent with the document that recorded an “Inner-Mound Shrine of Five Gods.” The main chamber includes mural paintings, red-colored representations of wooden bracket sets, painted double coffins, a coffin platform, and an offering altar. A large number of artifacts predominated by goldware and textiles were uncovered. Amongst them, a silver seal bearing the inscription “seal of the King of Achai, the nephew” provides critical evidence for the confirmation of the status and ethnic identity of the tomb occupant.

Ancient DNA from Tubo Kingdom-related tombs in northeastern Tibetan Plateau revealed their genetic affinity to both Tibeto-Burman and Altaic populations.

The rise of the Tubo Kingdom is considered asthe key period for the formation of modern groups on the Tibetan Plateau. The ethnic origin of the residents of the Tubo Kingdom is quite complex, and their genetic structure remains unclear. The tombs of the Tubo Kingdom period in Dulan County, Qinghai Province, dating back to the seventh century, are considered to be the remains left by Tubo conquerors or the Tuyuhun people dominated by the Tubo Kingdom. The human remains of these tombs are ideal materials for studying the population dynamics in the Tubo Kingdom. In this paper, we analyzed the genome-wide data of eight remains from these tombs by shotgun sequencing and multiplex PCR panels and compared the results with data of available ancient and modern populations across East Asia. Genetic continuity between ancient Dulan people with ancient Xianbei tribes in Northeast Asia, ancient settlers on the Tibetan Plateau, and modern Tibeto-Burman populations was found. Surprisingly, one out of eight individuals showed typical genetic features of populations from Central Asia. In summary, the genetic diversity of ancient Dulan people and their affiliations with other populations provide an example of the complex origin of the residents in the Tubo Kingdom and their long-distance connection with populations in a vast geographic region across ancient Asia.

A Central Asian Silver Dish with a Greek Mythological Scene found in Dulan (Qinghai)

One metal dish from Reshui royal Tibetan graves (Dulan, Qinghai Province) recently entered the collection of the Dulan County Museum after being confiscated by Chinese police. The scene on the dish is not easily distinguishable because of the bad state of preservation of this metalwork. The present short paper discusses the possibility that this scene could be identified as an episode of the Trojan War that included Ajax and Cassandra.

Typical Correlation Analysis between Forage Type Triticale Production Performance and Different Pilot Ecological Factors

Domestic and foreign researches on triticale mainly focus on hereditary traits and excellent characteristics, but there are few reports on triticale yield and quality in the severe cold pastoral areas of Gansu and Qinghai. In this study, Gannong 2 triticale cultivars have been bred and planted in typical ecological areas according to the characteristics of different ecological regions. By studying the relationship between quality traits and various ecological factors, the effects of different ecological factors on the quality of Triticale hay have been clarified, which provides a reasonable basis for future triticale breeding and large-scale and targeted planting layout. The production performance and nutritional qualities of Triticale Trial in Maqu County, Gansu Province and Gannong No. 2 in Dulan County, Qinghai Province are obviously superior to other pilot sites. Through reasonable fertilization, the production performance and nutritional quality of triticale are the best. Triticale production performance is significantly related to climatic factors in different pilots. The most suitable planting area for Gannong 2 is Maqu County, Gansu Province.

Satellite tracking reveals a new migration route of black-necked cranes (Grus nigricollis) in Qinghai-Tibet Plateau.

BackgroundThe black-necked crane (Grus nigricollis) is a vulnerable species and the only species that lives in the plateau. Five migration routes of different populations have been identified, but for cranes wintering in Nyingchi Prefecture, Tibet, the migration route and breeding/summering area are still unknown. The aim of this study was to investigate the spatio-temporal migration patterns of black-necked cranes in this area and to identify important areas for conservation.MethodsIn 2016, we fitted seven black-necked cranes in Nyingchi with GPS-GSM satellite transmitters to record their migration routes. We used ArcGIS 10.2 to visualize important stopover sites and the ‘ggplot’ function in R to analyze the migration patterns.ResultsFrom March 2016 to May 2019, we recorded nine spring migration and four autumn migration tracks from five individuals. Four individuals spent the breeding/summering season in Qinghai Lake, while the other spent the breeding/summering season in the Jinzihai Wetland of Dulan County, Qinghai Province. Detailed spatio-temporal information showed that the spring migration lasted 8.7 ± 4.6 days and covered 1,182.5 ± 90.4 km, while the autumn migration lasted 30 ± 10.6 days and covered 1,455.7 ± 138 km. Basom Lake and the Shazhuyu River were the most important stopover sites during the spring and autumn migrations, respectively. The cranes spent 4.4 ± 3.7 days in Basom Lake and 26.3 ± 10.7 days in the Shazhuyu River. The black-necked cranes mainly migrated during the daytime (>85 % of the fly points), and 81 % (17/21) of all stopover and roosting sites were in the valley or at lakeside swamps. Only 17.7% (516 / 2,914) of the data points for stopover and roosting sites were in protected areas.Main conclusionsOur study revealed the breeding/summering areas and migration routes of the black-necked cranes wintering in Nyingchi. These results contribute to a better understanding of the annual spatio-temporal migration patterns and the development of conservation plans for this vulnerable species.

青海省都兰县草原畜牧业演变及其影响——以巴隆乡为例

青海省都兰县草原畜牧业演变及其影响——以巴隆乡为例

Abnormal Rb/Sr ratio in lacustrine sediments of Qaidam Basin, NE Qinghai–Tibetan Plateau: A significant role of aeolian dust input

The Rb/Sr ratio is an important indicator of weathering intensity in both lacustrine and loess sediments because of the inertness of the Rb element and the activity of the Sr element during the weathering process. Generally, the environmental interpretation of Rb/Sr ratio proxy in lacustrine sediments is contrary to that in the loess-paleosol sequence: it shows a negative correlation between the Rb/Sr ratio and chemical weathering intensity in lacustrine sediments, but shows a positive pattern in the loess-paleosol sequence. However, in this study, we investigated the Rb/Sr ratio of a lacustrine core (ISL1A) from Qarhan Salt Lake (QSL) in eastern Qaidam Basin (QB), and found the Rb/Sr ratio indicated a positive correlation with regional precipitation. This pattern is similar to that of the loess-paleosol sequence rather than the lacustrine sediments. According to grain size statistics and the comparison of Rb/Sr ratio with other proxies (halite and calcite contents, grain size, and F values of grain size discriminant function), we preliminarily proposed that the abundant input of aeolian materials, transported by the strong northwest wind, cause these unexpected Rb/Sr ratio fluctuations in the ISL1A core. The comparison between background Rb and Sr elemental data of relevant regions and these of the core indicated the aeolian origin of Rb/Sr ratio in the lacustrine sediments, and the Rb and Sr elemental composition probably represents the geochemical characteristics of the dust source area. The Sr-Nd isotopic composition indicates that the erosive paleo-lake strata in western QB could be the origin of aeolian materials in lacustrine sediments in the QSL, as well as the loess deposits in Dulan County, Qinghai Lake Basin, and Xining Basin. The regional correlation between proxies of the ISL1A core and other aeolian records also supports the aeolian origin of detrital input in the core. Finally, we propose that the origin of the detrital input must be distinguished before the Rb/Sr ratio is applied as a weathering intensity proxy in lacustrine sediments, especially in arid basins.

Tree-Ring Dating of the Reshui-1 Tomb in Dulan County, Qinghai Province, North-West China.

Tuyuhun and Tubo were two important states that thrived in north-western China during AD 311-900 in parallel with the Han Chinese dynasties of Sui and Tang periods. The Reshui Tomb Cluster located in Dulan County of the north-eastern Tibetan Plateau is an important cultural relic of the Tuyuhun-Tubo age. The official excavations of the Reshui tombs were regarded as top events in archaeology in the 1980s and 1990s in China. The Reshui-1 Tomb is the largest one among the tombs in the area. Since its excavation, there have been debates on whether the owner of the tomb belonged to the Tuyuhun or Tubo ethnicity. Therefore, accurately dating the Reshui-1 Tomb has a critical place in studying the Tubo and Tuyuhun histories. We collected 7 discs and 11 increment cores of Qilian juniper (Juniperus przewalskii Kom.) from the exposed and fallen beams of the roof of the Reshui-1Tomb. The lengths of the 16 tree-ring records are between 69 and 152 years. Based on a previously developed master dating chronology using Qilian juniper samples from the eastern Qaidam Basin, the calendar dates of the 16 specimens were determined by the COFECHA program and visual dating procedure. The average inter-series correlation among the dated sample series is 0.696, indicating good quality of cross-dating. The year of the outermost rings is AD 715 for the 7 discs and 4 out of the 9 increment cores. Moreover, the ring-width variations of the samples are consistent with the existing chronologies from the region. The presence of late-wood of AD 715 in the samples indicated that the Reshui-1 Tomb was completed in late AD 715 or early 716, which means that the Reshui-1 Tomb was finished in the Tubo age. This date provides direct evidence for archaeologists to determine the owner’s ethnicity and identify of the Reshui-1 Tomb.

Three new species of genus Sinophorus Förster (Hymenoptera, Ichneumonidae) parasitizing twig and defoliating Lepidoptera.

Three new wasp species are described from the subfamily Campopleginae (Hymenoptera: Ichneumonidae), Sinophorus bazariae Sheng, sp. n., reared from Bazaria turensis Ragonot (Lepidoptera, Pyralidae) in Dulan County, Qinghai Province, China, S. nigrus Sheng, sp. n., reared from Epinotia rubiginosana rubiginosana (Herrich-Schäffer) (Lepidoptera, Tortricidae) in Weichang, Hebei Province, and S. zeirapherae Sheng, sp. n., reared from Zeiraphera grisecana (Hübner) (Lepidoptera, Tortricidae) in Liupanshan, Ningxia Hui Autonomous Region. A key to the species of Chinese Sinophorus is provided.

Implementation of Topography Factors in Habitat Assessment and Spatial Carrying Capacity Estimation for Tibetan Fox

Based on “Presence data”, we assessed the habitat quality according to the physical factor utilized by Tibetan fox in Gouli Township, Dulan County, Qinghai Province, China. The spatial carrying capacity of Tibetan fox was also estimated according to their minimum space requirements. A total of 4 topographical factors, elevation, slope, terrain ruggedness and slope position, were used to conduct habitat assessment for Tibetan fox. The suitability of habitat factors were determined by comparing the utilization by Tibetan fox and its availability based on 95% Bonferroni confidence interval. A comprehensive assessment criterion was set up for all topographic factors. For Tibetan fox, the elevations of 4 050 - 4 300 m, the slopes of 5 − 20°, the upper and lower slope positions were suitable habitat. Tibetan fox use terrain ruggedness non-selectively. According to the utilization of Tibetan fox on different topographic factors and the consistence of habitat utilization by different fox individuals, we set the comprehensive criterion as: Xi = (X2elevation x X2slope positionx Xslope x Xterrainrug gadness)1/6. The area of suitable habitat is about 17.4 km2, which take a percentage of 38.8% of research area. The area of most suitable habitat is only 0.4 km2. The home range of Tibetan fox ranges from 2.53 km2 to 4.99 km2, and the overlap index (OI) of different individuals were 0.16 − 0.66. The minimum space requirements of Tibetan fox are 2.09 − 3.55 km2, and the spatial carrying capacity of Tibetan fox in suitable habitat is 7−12. According to the habitat resource and monitoring results, we infer that the Tibetan fox population is keeping steady.

Paleofire indicated by triterpenes and charcoal in a culture bed in eastern Kunlun Mountain, Northwest China

A series of biomarkers were analyzed in the 4000 a B.P. loess sediments in Balong, Dulan County at the north of the eastern Kunlun Mountain in Northwest China using gas chromatography-mass spectrometry. Olean-2,13 (18)-ene, olean-2,12-ene, urs-2,12-ene and 5α14α17 α20R-stigmasterane identified in an ancient culture bed were observed in association with charcoal grains, believed to be the products of paleofire due to the anthropogenic activity in Qijia culture. These triterpenes were proposed to be derived from dehydration of oleanolic acid and ursolic acid present in angiosperms, and 5α14α17α20R-stigmasterane was derived from stenols; they both were formed during incomplete combustion. The n-alkane distributions show a shift in the dominant carbon from C27 or C29 to C31, indicative of the abrupt change in paleovegetation from woody to herbaceous plants driven by the changing paleoclimate at 4000 a B.P. after the Holocene Optimum. Coincidently, the Qijia agriculture culture began to collapse during the 200-year cooling and dryness, and was replaced by nomadism in the mountainous area. The paleofire identified is such a record as to document the change of ancient culture induced by paleoclimate change.

Land use change and its driving forces on the Tibetan Plateau during 1990–2000

Rapid economic development has spurred land use change in China since the Chinese government initiated its economic reform in 1978. Although many papers have analyzed the characteristics of land use change, especially cropland conversion to non-agricultural use affected by economic development in the developed regions of China, relatively less attention has been paid to studying the characteristics of land use change affected by both economic development and environmental changes in its undeveloped regions. This paper analyzes the land use change and its driving forces in Dulan County, Qinghai Province on the Tibetan Plateau during 1990–2000. The land use change was studied based on the landscape metrics change and transition matrix of land use types, while its driving forces were analyzed according to climatic changes and socioeconomic development. The study indicates that the increase of land use benefits was given great attention; however, the protection of arid environment did not attracted much attention. The study suggests that the land use should be based on the sustainable protection of arid environment on the Tibetan Plateau.

Precise timing of the Early Paleozoic metamorphism and thrust deformation in the Eastern Kunlun Orogen

In Dulan County, Qinghai Province NW China, the arc volcanic sequences in the northern side of the Central Fault of the East Kunlun were metamorphosed progressively from upper greenschist facies in the south to epidoteamphibolite facies in the north. High-angle thrust deformation was developed synchronously with the peak metamorphim and superimposed with later low-angle striking-slip deformation. Zircon U-Pb dating yields a concordant age of (448± 4) Ma for the metavolcanics. Syn-kinematic hornblende and muscovite separated from the high-angle thrusting belt give 40Ar–39Ar plateau age of (427± 4) Ma and 408 Ma, respectively. These results precisely constrain the timing of the closure of early Paleozoic volcanic basin (Proto-Tethys) over the eastern portion of the East Kunlun Orogen, and the thrust tectonic slice had a cool rate of ca. 9°C/Ma.

40Ar-39Ar and U-Pb ages of metadiorite from the East Kunlun Orogenic Belt: Evidence for Early-Paleozoic magmatic zone and excess argon in amphibole minerals

Single-grain zircon U-Pb and amphibole40Ar-39Ar dating have been conducted on a deformed and metamorphosed diorite in the East Kunlun Orogenic Belt, which intruded into the middle Proterozoic Kuhai Group exposed in the south of Xiangride region, Dulan County, NW Qinghai Province. The zircon gives a concordant U-Pb age of (446.5±9.1) Ma. The amphibole yields Ar plateau age of (488.0±1.2) Ma and an isochronal age of (488.9±5.6) Ma. Age results of both stepwise released Ar and conventional K-Ar analysis are remarkably higher than that of zircon U-Pb, suggesting that the amphibole contains excess argon and the amphibole plateau age cannot be taken as the timing of metamorphism or deformation. The zircon age is interpreted to be crystallization age of the diorite pluton, which suggests that an Early-Paleozoic magmatic zone indeed existed in the East Kunlun Orogenic Belt stretching along the region south to the Golmud, Normuhong and Xiangride.