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Northeastern China (northeastern + china)
Selected AbstractsEcosystem,atmosphere exchange of CH4 and N2O and ecosystem respiration in wetlands in the Sanjiang Plain, Northeastern ChinaGLOBAL CHANGE BIOLOGY, Issue 3 2009CHANGCHUN SONG Abstract Natural wetlands are critically important to global change because of their role in modulating atmospheric concentrations of CO2, CH4, and N2O. One 4-year continuous observation was conducted to examine the exchanges of CH4 and N2O between three wetland ecosystems and the atmosphere as well as the ecosystem respiration in the Sanjiang Plain in Northeastern China. From 2002 to 2005, the mean annual budgets of CH4 and N2O, and ecosystem respiration were 39.40 ± 6.99 g C m,2 yr,1, 0.124 ± 0.05 g N m,2 yr,1, and 513.55 ± 8.58 g C m,2 yr,1 for permanently inundated wetland; 4.36 ± 1.79 g C m,2 yr,1, 0.11 ± 0.12 g N m,2 yr,1, and 880.50 ± 71.72 g C m,2 yr,1 for seasonally inundated wetland; and 0.21 ± 0.1 g C m,2 yr,1, 0.28 ± 0.11 g N m,2 yr,1, and 1212.83 ± 191.98 g C m,2 yr,1 for shrub swamp. The substantial interannual variation of gas fluxes was due to the significant climatic variability which underscores the importance of long-term continuous observations. The apparent seasonal pattern of gas emissions associated with a significant relationship of gas fluxes to air temperature implied the potential effect of global warming on greenhouse gas emissions from natural wetlands. The budgets of CH4 and N2O fluxes and ecosystem respiration were highly variable among three wetland types, which suggest the uncertainties in previous studies in which all kinds of natural wetlands were treated as one or two functional types. New classification of global natural wetlands in more detailed level is highly expected. [source] Genetic diversity and population structure of indigenous yellow cattle breeds of China using 30 microsatellite markersANIMAL GENETICS, Issue 6 2007G. X. Zhang Summary Twenty-seven domesticated yellow cattle breeds of China and three introduced cattle breeds were analysed by means of 30 microsatellite markers to determine the level of genetic variation within and among populations as well as the population structure. In all, 480 microsatellite alleles were observed across the 30 breeds with the mean number of alleles per locus of 9.093 for native breeds and 6.885 for the three introduced breeds. Mean F -statistics (0.08) for Chinese native cattle breeds implied that 92% of the total genetic variation was from genetic differentiation within each breed and 8% of the genetic variation existed among breeds. A phylogenetic tree was constructed based on Nei's genetic distances, and three clusters were obtained. According to the tree, the three introduced breeds were distinct from the 27 native breeds. The indigenous cattle breeds were divided into two clusters, one cluster including five humpless breeds and the other cluster containing 22 humped breeds. This study identifies multiple origins of yellow cattle of China from Bos taurus and Bos indicus. Furthermore, population structure analysis implies that there are possibly five independent original domestications for yellow cattle in China. Four of five origins were four different Bos indicus types, mainly in areas of the Chang Jiang, the Zhu Jiang River basin, the Yellow River and the Huai River basin. The other origin was for Bos taurus type of Mongolian descent, mainly located in Northwestern China, the Mongolian plateau and Northeastern China or north of the Great Wall. [source] New Mesozoic Mesopsychidae (Mecoptera) from Northeastern ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2010REN Dong Abstract: The Mesozoic family Mesopsychidae Tillyard, 1917 presently consists of seven described genera and 13 species from the mid-Triassic to the Early Cretaceous of Australia, South Africa and Eurasia. In the present paper one new genus and three new species of fossil mesopsychids are described that add significant distributional and stratigraphic extensions to the family. This finding documents the first formal record of fossil Mesopsychidae in China. Both Lichnomesopsyche gloriae gen. et sp. nov. and L. daohugouensis gen. et sp. nov. were found from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, whereas Vitimopsyche kozlovi sp. nov., of mid Early Cretaceous age, was collected from the Jehol Biota of northern Hebei Province. This new, well-preserved material from China reveals complete and previously unknown body features, including head, antennae, mouthparts, legs and abdomen. The delicate and long proboscides of these new taxa indicate that they were feeding on externally exposed, nutrient-rich fluids of gymnospermous ovulate fructifications, and incapable of piercing surface epidermis , attributable principally to the absence of stylets. These proboscides originated, perhaps multiply, among basal Mecoptera and are functionally and structurally convergent with equivalent mouthparts borne by fossil and extant Diptera, Lepidoptera, Neuroptera and Coleoptera. [source] Two New "Notostracans", Chenops gen. nov. and Jeholops gen. nov. (Crustacea: Branchiopoda: ?Notostraca) from the Yixian Formation, Northeastern ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2010Thomas A. HEGNA Abstract: The Early Cretaceous Jehol biota of northeastern China contains a diverse group of notostracans, including two genera, Chenops and Jeholops, described here. Chenops is characterized by a combination of an ovate carapace, narrow anal plate, equant distal endites and endopod on the anterior thoracic limbs. In addition to the new species, Chenops yixianensis, the genus also provisionally includes Prolepidurus oblongus Oleynikov, 1968. Jeholops, however, is monotypic, represented by the new species Jeholops hongi. It is characterized by a combination of kazacharthran and notostracan features unique to this taxon. Both new genera are provisionally placed in the taxon Notostraca. More detailed work exploring the morphology of exceptionally-preserved branchiopod crustaceans is needed. The difficulties in placing fossil notostracans into a phylogenetic framework are discussed. [source] A New Boreopterid Pterodactyloid Pterosaur from the Early Cretaceous Yixian Formation of Liaoning Province, Northeastern ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2010Junchang LÜArticle first published online: 22 MAR 2010 Abstract: A new boreopterid pterosaur: Zhenyuanopterus longirostris gen. et sp. nov. from the Yixian Formation of western Liaoning is erected, based on the complete skeleton with a skull and lower jaws preserved. It is characterized by: a large boreopterid pterosaur with a high number of teeth, where the anterior teeth are much larger than posterior ones; the length of the dorsal + sacral vertebrae is nearly half the length of the skull; ratio of the length of the humerus to metacarpal IV is approximately 91% and the, humerus, femur and third wing phalanx are all equal in length and the feet are specially small. It represents the largest boroepterid pterosaur discovered from western Liaoning and its surrounding areas so far [source] New Fossils of Eoptychopteridae (Diptera) from the Middle Jurassic of Northeastern ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2009Jianying HAO Abstract: Three new species of the extinct genus of Eoptychopterina from the Eoptychopteridae family, Eoptychopterina antica sp. nov., Eoptychopterina adnexa sp. nov., and Eoptychopterina mediata sp. nov., are described and illustrated. These three new species are established based on fossil specimens with bodies and complete wings. All were collected from the Middle Jurassic Jiulongshan Formation of Daohugou in eastern Inner Mongolia, China. Based on the new materials, the name of two species in Eoptychopterina from China,Eoptychopterina elenae Ren and Krzeminski and Eoptychopterina gigantea Zhang,is sysnonymum Junius. [source] New Genus and Species of Fossil Dragonflies (Insecta: Odonata) from the Yixian Formation of Northeastern ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 3 2006ZHANG Binglan Abstract, Two well-preserved fossil dragonflies from the Late Mesozoic Yixian Formation, Liaoning Province, China are described and assigned to a new genus, Sopholibellula gen. nov. in Araripelibellulidae Bechly, 1996, closely related to the type genus Araripelibellula. This new genus differs from Araripelibellula in the following characters: origins of RP and MA distinctly separated at arculus in both pairs of wings; anal loop wider and shorter, with Y-shaped veins inside; MA and IR2 not zigzag; several small intercalary veins present in the postdiscoidal area of hindwing; cells smaller and much more dense, especially in the apex and hind margin; bigger in size. Structures, including head, abdomen and parts of legs, were first described in details of this family. [source] Energy budget above a temperate mixed forest in northeastern ChinaHYDROLOGICAL PROCESSES, Issue 18 2007Jiabing Wu Abstract Components of the energy budget were measured continuously above a 300-year-old temperate mixed forest at the Changbaishan site, northeastern China, from 1 January to 31 December 2003, as a part of the ChinaFlux programme. The albedo values above the canopy were lower than most temperate forests, and the values for snow-covered canopy were over 50% higher than for the snow-free canopy. In winter, net radiation Rn was generally less than 5% of the summer value due to high albedo and low incoming solar radiation. The annual mean latent heat LE was 37·5 W m,2, accounting for 52% of Rn. The maximum daily evaporation was about 4·6 mm day,1 in summer. Over the year, the accumulated precipitation was 578 mm; this compares with 493 mm of evapotranspiration, which shows that more than 85% of water was returned to the atmosphere through evapotranspiration. The LE was strongly affected by the transpiration activity and increased quickly as the broadleaved trees began to foliate. The sensible heat H dropped at that time, although Rn increased. Consequently, the seasonal variation in the Bowen ratio , was clearly U-shaped, and the minimum value (0·1) occurred on a sunny day just after rain, when most of the available energy was used for evapotranspiration. Negative , values occurred occasionally in the non-growing season as a result of intensive radiative cooling and the presence of water on the surface. The , was very high (up to 13·0) in snow-covered winter, when evapotranspiration was small due to low surface temperature and available soil water. Vegetation phenology and soil moisture were the key variables controlling the available energy partitioning between H and LE. Energy budget closure averaged better than 86% on a half-hourly basis, with slightly greater closure on a daily basis. The degree of closure showed a dependence on friction velocity u*. Copyright © 2006 John Wiley & Sons, Ltd. [source] Connections of Siberian snow onset dates to the following summer's monsoon conditions over Southeast AsiaINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 12 2005Hengchun Ye Abstract This is an exploratory study of possible links between the conditions of early season Eurasian snowfall and the following year's Southeast Asian summer monsoon. Forty years (1950,1995) of historical records are used to examine the statistical connections between early season snow cover onset dates over northern Eurasia and the following year's summer monsoon over Southeast Asia. We found that the time of snow onset is significantly associated with warm season rainfall over Southeast Asia. The most persistent connection is between northeastern Siberian snow onsets and summer monsoon strength over India and northeastern China. This connection seems to be more clearly shown during the mature stage and monsoon withdrawal and is reflected in all three aspects of monsoon characteristics. In other words, the earlier snow cover onset (more snow cover during the early season) over northeastern Siberia, the more precipitation and moisture convergence, the higher prevalence of a southwesterly monsoon wind, and the later monsoon withdrawal over Southeast Asia. The revealed connection is likely through atmospheric circulation associated with early season land surface snow cover processes independent of El Ñino conditions. The authors suggest that more studies are needed to fully understand the circuitous connections between Eurasian snowfall and the Southeastern Asian monsoon. Copyright © 2005 Royal Meteorological Society. [source] Intra-seasonal variability of wintertime temperature over East AsiaINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2004Dao-Yi Gong Abstract There has been a profound warming over East Asia during the winter months (November through to March) over the past few decades. The goal of this study is to address the question of whether the daily temperature has become more variable in conjunction with this warming by using observed temperature data obtained from 155 Chinese and Korean stations. Prior to the analysis, the annual cycle is removed to obtain daily temperature anomalies for each winter for each station. Results show that the intra-seasonal variance generally decreases, implying that the daily temperatures are becoming less variable. Considering all stations as a whole, the rate of change is ,0.49°C2 per decade (equivalent to ,3.59% per decade). The changes are more robust in the northeastern portion of China. In contrast, there are no dominant trends for the skewness coefficients, except for clear negatively skewed trends in northeastern China. These results are consistent with an increase in the number of extremely cold events. Over the region, the frequency of low-temperature extremes (as low as below minus two standard deviations) increases at a rate of change of 0.26 days per decade, significant at the 95% confidence level. Both the Siberian high and Arctic oscillation (AO) exert a notable influence on the temperature variance. Intra-seasonal variance of the Siberian high and AO are significantly correlated with the temperature variance, whereas the seasonal mean state of the AO affects the temperature variance by modulating the high-frequency components of the Siberian high. The intra-seasonal variance of the Siberian high tends to decline at a rate of change of ,10.7% per decade, significant at the 99% level; meanwhile, the mean wintertime AOs have strengthened in the last few decades. These two climate features together make a considerable contribution to the changes in intra-seasonal temperature variance in East Asia. Copyright © 2004 Royal Meteorological Society [source] Sonographic findings of active Clonorchis sinensis infectionJOURNAL OF CLINICAL ULTRASOUND, Issue 1 2004Dongil Choi MD Abstract Purpose The aim of this study was to document the characteristic sonographic findings of clonorchiasis for the diagnosis of active infection in an endemic area. Methods In a village in northeastern China, residents underwent fecal examinations for detection of Clonorchis sinensis eggs. Shortly thereafter, residents were examined with abdominal sonography. An experienced radiologist performed the sonographic examinations and analyzed the findings. Subjects whose fecal examinations were positive for eggs were considered to have active clonorchiasis; those whose examinations were negative for eggs were used as control subjects. The distinguishing sonographic features of active clonorchiasis were identified by stepwise logistic regression analysis. Results The study population comprised 457 subjects; fecal examinations revealed C. sinensis eggs in 316 and no eggs in 141. Four sonographic findings distinguished subjects with active clonorchiasis from control subjects: increased periductal echogenicity (p < 0.001; R = 0.11; sensitivity, 35%; specificity, 91%), floating echogenic foci in the gallbladder (p < 0.001; R = 0.09; sensitivity, 28%; specificity, 94%), diffuse dilatation of the intrahepatic bile ducts (p < 0.01; R = 0.03; sensitivity, 67%; specificity, 48%), and gallbladder distention (p < 0.05; R = 0.02; sensitivity, 3%; specificity, 100%), in decreasing order of significance. Among these 4 sonographic findings, increased periductal echogenicity and floating echogenic foci in the gallbladder were more significantly associated with active infection than were the other 2. Conclusions Increased periductal echogenicity and floating echogenic foci in the gallbladder were identified as the 2 most significant findings for the sonographic diagnosis of active C. sinensis infection. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 32:17,23, 2004 [source] Degradation of permafrost in the Xing'anling Mountains, northeastern ChinaPERMAFROST AND PERIGLACIAL PROCESSES, Issue 3 2007Huijun Jin Abstract Permafrost in the Da and Xiao Xing'anling Mountains in northeastern China is warm, thin and sensitive to climatic warming. In the 1970s, the southern limit of permafrost (SLP) was empirically correlated to the ,1 to 0°C isotherms of mean annual air temperature (MAAT) in the western part of the Da Xing'anling Mountains, to about 0°C in the northern part of the Songnen Plain, and to 0 to +1°C in the eastern part of the Xiao Xing'anling Mountains. Climate warming and deforestation have led to permafrost degradation as shown by deepening of the active layer, thinning permafrost, rising ground temperatures, expanding taliks and the disappearance of permafrost patches. The present position of the SLP was estimated using the ,1.0 to +1.0°C MAAT isotherms for 1991,2000. Compared to the SLP in the 1970s, areas of sporadic discontinuous and isolated patchy permafrost have decreased by 90,000,100,000,km2, or 35,37% of their total areal extent (260,000,270,000,km2) in the 1970s. Recent field observations along the Hei'he to Bei'an Highway, the proposed Mo'he to Daqing Crude Oil Pipeline route and the Hai'lar to Daqing Highway confirm these changes. Continuing northward shifting of the SLP is likely to occur during the next 40,50 years under a warming of 1.0,1.5 °C, reducing the permafrost areal extent to an estimated 35% of that in the 1970s and 1980s. Copyright © 2007 John Wiley & Sons, Ltd. [source] Middle Jurassic Coptoclavidae (Insecta: Coleoptera: Dytiscoidea) from China: a Good Example of Mosaic EvolutionACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2010WANG Bo Abstract: Adults of the aquatic coptoclavid beetles (Coleoptera: Adephaga: Dytiscoidea), described from four Middle Jurassic fossil localities in Inner Mongolia and Liaoning in northeastern China, are attributed to Daohugounectes primitives Wang, Ponomarenko and Zhang, 2009, which was previously proposed after study of larvae. The generic name Timarchopsis Brauer, Redtenbacher and Ganglbauer, 1889 is proposed as a substitute for the preoccupied and junior homonym Necronectes Ponomarenko, 1977, non Milne-Edwards, 1881. Furthermore, the subfamily name Necronectinae Ponomarenko, 1977 is substituted by the available name Timarchopsinae. Daohugounectes is placed into Timarchopsinae because its adults have long, slightly apically widened tibiae and small femoral plates. The adults of this genus differ from those of other Timarchopsinae in the following features: antennae short and widened in the middle part; basal segments of protarsi not cut apically; metaventrite with a triangular plate. The larvae look like somewhat primitive forms in the subfamily Timarchopsinae. In contrast to these primitive larvae, the adults with some advanced characters can be regarded as among the most advanced forms in the subfamily Timarchopsinae, and probably represent a transition between the Timarchopsinae and Charanoscaphinae. Such mosaic evolution within Daohugounectes indicates that the evolutionary process of aquatic beetles is far more complex than previously thought. [source] Two New "Notostracans", Chenops gen. nov. and Jeholops gen. nov. (Crustacea: Branchiopoda: ?Notostraca) from the Yixian Formation, Northeastern ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2010Thomas A. HEGNA Abstract: The Early Cretaceous Jehol biota of northeastern China contains a diverse group of notostracans, including two genera, Chenops and Jeholops, described here. Chenops is characterized by a combination of an ovate carapace, narrow anal plate, equant distal endites and endopod on the anterior thoracic limbs. In addition to the new species, Chenops yixianensis, the genus also provisionally includes Prolepidurus oblongus Oleynikov, 1968. Jeholops, however, is monotypic, represented by the new species Jeholops hongi. It is characterized by a combination of kazacharthran and notostracan features unique to this taxon. Both new genera are provisionally placed in the taxon Notostraca. More detailed work exploring the morphology of exceptionally-preserved branchiopod crustaceans is needed. The difficulties in placing fossil notostracans into a phylogenetic framework are discussed. [source] New Jurassic Pseudopolycentropodids from China (Insecta: Mecoptera)ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2010Dong REN Abstract: In this paper two new species of fossil Pseudopolycentropus Handlirsch, 1906 are described: Pseudopolycentropus janeannae sp. nov. and P. novokshonovi, sp. nov. All of them were recovered from the Middle Jurassic non-marine sedimentary strata of northeastern China. The new material from China reveals that the early diversification of pseudopolycentropodids was well underway by the Middle Jurassic. [source] Cretaceous Volcanic Events in Southeastern Jilin Province, China: Evidence from Single Zircon U-Pb AgesACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 6 2008CHEN Yuejun Abstract: Mesozoic volcanic rocks in southeastern Jilin Province are an important component of the huge Mesozoic volcanic belt in the northeastern area. Study of the age of their formation is of great significance to recognize Mesozoic volcanic rule in northeastern China. Along with the research of rare Mesozoic biota and extensive Mesozoic mineralization in western Liaoning, a number of researchers have focused on Mesozoic volcanic events. The authors studied the ages of the Cretaceous volcanic rocks in southeastern Jilin Province using single Zircon U-Pb. The result shows that the Sankeyushu Formation volcanic rocks in the Tonghua area are 119.2 Ma in age, the Yingcheng Formation in the Jiutai area 113.4±3.1 Ma, the Jinjiatun Formation in Pinggang Town of Liaoyuan City and the Wufeng volcanic rocks in the Yanji area 103.2±4.7 Ma and 103.6±1 Ma, respectively. Combined with the data of recent publication on volcanic rocks ages; the Cretaceous volcanic events in southeastern Jilin Province can be tentatively subdivided into three eruption periods: 119 Ma, 113 Ma and 103 Ma. The result not only provides important chronology data for subdividing Mesozoic strata in southeastern Jilin Province, establishing Mesozoic volcanic event sequence, discussing geological tectonic background, and surveying the relation between noble metals to the Cretaceous volcanic rocks, but also offers important information of Mesozoic volcanism in northeastern China. [source] Three New Stoneflies (Insecta: Plecoptera) from the Yixian Formation of Liaoning, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2008LIU Yushuang Abstract: Three new genera and species Archaeoperla rarissimus gen. et sp. nov. (Perlidae), Liaotaenionema tenuitibia gen. et sp. nov. (Taeniopterygidae) and Parvinemoura parvus gen. et sp. nov. (?Nemouridae) are described and illustrated. All of them were collected from Yixian Formation of the western Liaoning, China. Hitherto, A. rarissimus is the oldest species possessing typical characters of Perlidae; the finding of L. tenuitibia indicates taeniopterygids once lived in the northeastern China in the late Mesozoic, but frequent volcanic activities, climate changes, or other environmental changes might have resulted in the disappearance of Taeniopterygidae in northern China after Mesozoic. Ancestral groups of Nemouridae have been abundant from Middle Jurassic, and male genitalia of P. parvus gen. et sp. nov. has been developed and similar to extant Nemouridae in the late Mesozoic. The stonefly fossils found from Yixian Formation are not divers at the species level, but rich at the family level. The diversity of stonefly implies different microclimate existed in the northeastern China at that time. A large old lacustrine basin existed in the western Liaoning, surrounded by hygrophilous plants on swampland and lake shore, warm and humid; tall arbor and boscage on the hillside nearby, mild and dry; mountains in the distance, rivulets running among the mountains, cool and wet. Many insects, prefer cool climate (e.g. stonefly, raphidiopterans, et al.), lived in the mountains with rivulets. [source] The First Mesozoic Heterodactyl Bird from ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 5 2006ZHANG Zihui Abstract: Dalingheornis liweii gen. et sp. nov., a new enantiornithine bird was collected from the early Cretaceous Yixian Formation in northeastern China. It is the first record of a highly specialized heterodactyl foot in Mesozoic birds. The Y-shaped furcula with short hypocleidum is different from that of other enantiornithines. The minor metacarpal is robust and longer than the major metacarpal. A long bony tail composed of 20 caudal vertebrae with chevrons resembling those of dromaeosaurids and thus, highlighting again the evolutionary relationship between birds and non-avian theropods. Well-preserved alula feathers and a heterodactyl foot provide strong evidence for the arboreal habit of Dalingheornis. [source] A New Symmetrodont Mammal with Fur Impressions from the Mesozoic of ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2003Guillermo W. ROUGIER Abstract, Western Liaoning of northeastern China is world-renowned for the Mesozoic Jehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossil angiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preserved hairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao, western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and life habits of Mesozoic symmetrodont mammals. 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