Active tectonic deformation and its seismic-geological significance of boundary faults of the Daxing Uplift and Langgu-Dachang Depression,Beijing Plain,China

Boundary faults of the Daxing Uplift and Langgu-Dachang Depression are located in the southeastern region of the Beijing Plain and directly control the sedimentation,tectonic evolution,and strong seismic activity of the plain.The Sanhe-Pinggu earthquake of Ms 8.0 occurred in 1679,but the active tectonic deformation characteristics of the boundary have been rarely discussed.In this study,the active tectonic deformation characteristics of the Daxing Uplift and Langgu-Dachang Depression boundary rupture were investigated by collecting and analyzing the results of previous works,supplementing three shallow-seismicexploration control lines at locations where the data are lacking,and carrying out borehole combined profile exploration and optically stimulated luminescence dating at local breakpoints.Results show that the Daxing Uplift and Langgu-Dachang Depression boundary faults constitute an active tectonic deformation zone with~50 km distance between Mafang and Niubaotun towns and then extends to both ends to form a deep and large fault that cuts through the earth’s crust.The activity of the Daxing Uplift eastern boundary fault may be divided into two sections near Anding town,with the early-to-middle Late Pleistocene gradually weakening in the northwest and the Holocene gradually weakening in the southwest.Moreover,the activity of the Xiadian fault may be divided into two sections near the Chaobai River:the Holocene gradually weakening in the northwest and the early-to-middle Late Pleistocene gradually weakening in the southwest.The boundary fault of the Daxing Uplift and Langgu-Dachang Depression has an~43 km seismic gap around Niubaotun town,which has a high risk of Ms 6.0-7.0 earthquakes.This investigation into the active tectonic deformation characteristics of the boundary fault of the Daxing Uplift and Langgu-Dachang Depression is crucial for analyzing the strong earthquake rupture behavior and the future risk of strong earthquakes in this area.It also contributes greatly to the study of the tectonic pattern evolution of the North China Plain and Beijing Plain.

Landscape change on burned blanks in Daxing'an Mountains

Daxing抋n Mountains was one of the most important forest areas in China, but it was also an area which was prone to suffering forest fire. The catastrophic forest fire that occurred in Daxing抋n Mountains on May 6, 1987 devastated more than 1.33?06 hm2 of natural forests, which leaded to the formation of some mosaic areas with different burn intensities. Two forest farms of Tuqiang Forest Bureau (124?5-122?8E, 53?4-52?5N) were chosen as a typical area to analyze the post-fire landscape change by drawing and comparing the two digital forest stand maps of 1987 and 2000. The landscape lands of forest were classi-fied into 12 types: coniferous forest, broadleaf forest, needle-broadleaf mixed forest, shrub, nursery, harvested area, burned blanks, agricultural land, swamp, water, built-up, grass. The results showed that: 1) The burned blanks was almost restored, some of them mainly converted into broadleaf forest land during the process of natural restoration, and coniferous forest land by the artificial re-forestation, and the others almost changed into swamp or grass land; 2) The proportion of forest area increased from 47.6% in 1987 to 81.3% in 2002. Therefore, a few management countermeasures, such as the enhancing peoples consciousness of fire-proofing and constructing species diversity, were put forward for forest sustainable development.

A new pathotype characterization of Daxing and Huangyuan populations of cereal cyst nematode(Heterodera avenae) in China

The cereal cyst nematode（CCN, Heteroder aavenae） causes serious yield loss on cereal crops, especially wheat, worldwide. Daxing population in Beijing City and Huangyuan population in Qinghai Province, China, are two CCN populations. In this study, the CCN pathotypes of Daxing and Huangyuan populations were characterized by tests on 23 standard ＂International Test Assortment＂ with the local species Wenmai 19 as the susceptible control. Tested materials were grouped by three nematode populations＇ virulence on resistant genes（Rha1, Rha2, Rha3, Cre1） and nonresistant genes, varieties and lines. Both Daxing and Huangyuan populations were avirulent to Ortolan（Ha1）. Barley cvs. Ortolan, Siri, Morocco, Bajo Aragon 1-1, and Martin 403-2 were all resistant to both populations. Cultivars Herta, Harlan 43 and wheat Iskamish-K-2-light were all susceptible to Huangyuan population, all of them, however, were resistant to Daxing population. The other five oats were all resistant to the two tested CCN populations. Except Iskamisch K-2-light, all the other wheat cultivars（Capa, Loros×Koga, AUS 10894, and Psathias） were susceptible to Daxing population. Because the pathotypes of the two tested CCN populations in Beijing and Qinghai were not identical to any of the 13 pathotypes previously characterized by the test assortment, we classified Daxing and Huangyuan populations as the new pathotypes, named Ha91.

Site classification of the eastern forest region of Daxing'an Mountains

Based on the plot data from the investigation and the theory of forest ecology and ecological system,the site classification of the eastern forest region of Daxing’an Mountains was made by mean of mathematical method. The main factors were slope, thickness of soil layer, slope position and slope aspect. Grades of slope were used as the division standard for site type group. The slope aspect, slope position and thickness of soil layer were used as the division standards for site type. Altogether 7 site type groups and 15 main site types were determined the region. It provided reliable fundamental basis for the reasonable management and planting design in the area.

Spring habitat selection of sables in Daxing'an Mountains

This paper studies the habitat selection of sables (Martes. zibellina) in spring adopting radio-tracking and GPS (Global Positioning System) in Daxing’an Mountains of China. Sables liked mature and elder forest, but it avoided uncovered and young growth land. In spring sables had strong selection to medium cover-degree forest, but it avoided widen ground and especial high cover-degree forest. On the contrary sables didn’t have the strong selection to shrubs cover-degree, but strong selection to dominant tree species, slope degree and slope direction, especially sable liked medium and lower slope. At the same time, sables had the strong selection to the log’s density and the crown’s cover-degree. Generally it avoided high elevation and lower slope land.

Geochemistry and tectonic significance of Early Cretaceous granites in Highland 1248 of Daxing'anling

The Early Cretaceous granitic complex in Highland 1248 of Daxing'anling successively consists of intruded granodiorite,monzonite granite and syenite granite. Through test analysis on the major,trace and rare earth elements of the intrusive complex,this study focuses on the source characteristics and tectonic environment of the original magma of intrusive complex. The results show that the intrusive rocks in Highland 1248 are meta-aluminous-peraluminous rocks in calc-alkaline series with homologous characteristics in δEu negative anomalies; the complex is enriched in LILE( Rb,Cs and K) and depleted in HFSE( lanthanide,Sc,Y,U,Nb and Ta),displaying the geochemical characteristics of I-type granites in active continental-margin subduction zones. The complex also has the characteristics of granites after the collision of plate with rich aluminum and high potassium,but significantly depleted Nb,Ta,Ti,P and other elements,i. e. in the orogenic evolutionary stage. The zircon U-Pb SHRIMP isotopic apparent age of the complex in Highland 1248 is 140. 0--141. 0Ma,and the formation time is in Early Cretaceous.

Population Characteristics of Dendrolims Superans in Daxing'an Mountains

Dendrolims superans produced one generation every two years Large larvae and small larvae exist at the sametime. lt broke out in Daxiang an Mountains in 1990. and seriously destroyed growth of Larix gmelum Rupr In order to control D Superans.the population properties of D.superans were stedied from 1991 to 1992 including sex ratio.age distribution. pattern etc.. The sex ratio of D. superans population is The larvae age distrihution indicates that larvaeover 5 instar is less than younger larvae under 4 instar in Yongqing forest farm- but the younger larvae under 4 instar is morethan larvae over 5 instar in Hanjiayuanzi Forest Farm. The population of D. superans in Yongqing Farm has heen declining.and incrcasing in Hanjiayuanzi. Pupae and eggs are mainly distributed in middle and lower crowns layer of trees. respec-tively account for 66% and 59.5%, of total individuals. The pupae in higher cown layer is lightly regular distrihution. andclumping distribution middle and lower crowns layer of trees. The eggs in higher crown is light clumpin1g distribution. andrandom in middle and low crown of tree.

Quantitative dynamics on stimulating regeneration and sowing seedlings of Larix gmelinii in Daxing'an Mountains

To understand the quantitative dynamics and death reason of stimulating regeneration seedlings is significant for stimulating the natural regeneration ofLarix gmelinii and implement of conservation project of natural forest. This paper summarized location observations and directly-seeding simulation experiments of six permanent sample plots that were set up after the seed bumper harvest year ofLarix gmelinii in 1989. The study showed that stimulating natural regeneration seedlings had a large mortality in the first three years, especially in the first year of seedling emergence. After three years seedlings died less and stepped into the stable regeneration stage. A large number of seedlings died of sunscald as the primary death reason. For those areas of good site conditions and rich soil, damping-off would cause seedlings to death in large quantities. The task of stimulating regeneration is mainly to get rid of the litter (forest floor) on burned areas. By means of promoting measures, emergence rate of sown seeds would be several times and dozens of times higher than that of seed shedding on the condition of retention of forest floor. Promoting the regeneration need to select the suitable site against great slope and low-lying lands; at the same time, be careful of the avoidance of frost heaving by depression water.

Classification,metallogenesis and exploration of silver deposits in Daxing’anling of Inner Mongolia and its adjacent areas

By the end of 2020,83 silver deposits(or ore occurrences),including four super-large-scale deposits,nine large-scale deposits,33 medium-scale deposits and 37 small-scale deposits or ore occurrences,have been proved.The amount of silver metal exceeds 86000 t with average grade of 100 g/t,which makes Daxing’anling region one of the the most important silver ore belt in China.However,the metallogenic characteristics and metallogenesis need to be clarified.The silver deposits in the study area are classified into three main types,which are magmatic hydrothermal vein type,continental volcano-subvolcanic type and skarn type,respectively.The supergiant deposits include the Shuangjianzishan deposit(silver metal amount of 15214 t with average grade of 138 g/t),the Baiyinchagandongshan deposit(silver metal amount of 9446 t with average grade of 187 g/t),the Huaobaote deposit(silver metal amount of 6852 t with average grade of 170 g/t),and the Fuxingtun deposit(silver metal amount of 5240 t with average grade of 196 g/t).The silver deposits are mainly distributed in the central and south of the Daxing’anling area,and mainly formed in the Yanshanian period.The silver polymetallic deposits in the Daxinganling area are significantly controlled by regional faults and the junction zone of volcanic rock basins and their margins.The north-east trending deep faults are the most important ore-controlling structures in this area.The distribution of silver polymetallic deposits along the main faults is obvious,and the intersection area of multiple groups of faults often form important mine catchments.The Permian is the most important ore-bearing formation in this area,but some important silver polymetallic deposits occur in Mesozoic volcanic basins or pre-Mesozoic strata.The magmatic rocks related to mineralization are mainly intermediate acidic or acidic intrusions,intermediate acidic lavas,pyroclastic rocks,and small intrusions of ultra-shallow or shallow facies of the Yanshanian Period.The mineralization element combination is mainly determined by the elemental geochemical background of surrounding rocks or source layers.In addition,the type of deposit,the distance from the mineralization center,and the degree of differentiation of ore-forming rock mass are also important influence factors.The article analyzes the prospecting prospects of each silver deposit type in the study area,discusses the relationship between mineralization center and deep prospecting,and proposes that porphyry silver deposits should be paid attention to.In the prospecting and exploration of silver deposits,comprehensive evaluation and multi-target prospecting need to be strengthened because silver can coexist or be associated with a variety of metals.

Zircon SHRIMP U-Pb Dating and Geochemical Characteristics of Late Variscan Granites of the Daitongshan Copper Deposit and Lamahanshan Polymetallic-Silver Deposit, Southern Daxing'anling, China

Daxing＇anling （大兴安岭） area is one of the regions that Phanerozoic granites are extremely developed in NW China. At present, the Hercynian granitoid research lags behind the Mesozoic granitoid research. In this article, we have taken systematic petrochemistry and geochronology researches on the Hercynian granitoids in Daitongshan （代铜山） copper deposit and Lamahanshan （喇嘛罕山） silver poly- metallic deposit, which were located at southern section of Daxing＇anling metallogenic belt. Zircon SHRIMP U-Pb dating results show that, the granite aplites in Daitongshan and the gneissic granites inLamahanshan were formed at （265±5）-（268±9） Ma and （252±2）-（252.6±3.4） Ma, respectively, which were both the products of late Herynian tectonic-magmatic events. Samples from Lama- hanshan are characterized by high SiO2 （69.72 wt.%-74.65 wt.%）, high potassium （3.53 wt.%-4.55 wt.%） and low P205 （0.03 wt.%0.12 wt.%）, aluminum saturation index （A/CNK） range from 0.95 to 0.98, Rb, Nd and K are en- riched, whereas the elements such as Nb, Ta, P and Ti are depleted, which belong to I-type grani- toids. Characteristics of samples from Daitong- shan are similar to H-type granitoids. The magmasource may be mostly originated from the lithospheric mantle component which were transformated or affected by the subduction components, and its formation may be closely related with the subduction and orogenesis of the Paleo-Asian Ocean.

Key technological innovations in the construction of the main terminal of Beijing Daxing International Airport

Beijing Daxing International Airport,a major landmark project in China and a new driver for national development,will represent the direction for the development of civil aviation airports in China.The airport,situated in the junction of Nangezhuang,Daxing District,Beijing City and Gu’an County,Hebei Province,has seen its north terminal area and north terminal built in the first phase,covering a total construction area of about 1.4 million m2.The north terminal area is designed to have an annual throughput of 45 million passengers.

Research on Development of Leisure Agriculture in Beijing Suburb

Leisure agriculture in Beijing suburb enjoys a promising prospect with wide customer sources and policy supports. The research performed analysis on man- agement status and employees of leisure agriculture-oriented industrial parks in Daxing District by questionnaire survey in order to seek development strategies and promote transformation and updating of leisure agriculture in Daxing District. The re- sults showed that there are some problems in leisure agricultural parks in terms of software or hardware and some suggestions are proposed, including environment updating, product updating, brand updating, industry structure updating, scale updat- ing, organization updating, and talent updating, in order to promote social brand and improve economic profits of leisure agriculture in Daxing District.

儿童原发性肾上腺皮质功能减退的临床特征和基因突变研究

目的分析儿童原发性肾上腺皮质功能减退患者的临床特征及其DAX1、SF1基因突变的发生率,探讨导致该病可能的分子机制。方法选择原发性肾上腺皮质功能减退的男性患儿25例,观察患儿的临床特征并行辅助检查。抽提外周血基因组DNA,对DAX1基因2个外显子(外显子1和2)的PCR扩增产物进行测序分析;无突变者行SF1基因(外显子2~7)突变筛查。结果患儿均有不同程度的皮肤色素沉着、乏力、恶心、呕吐及脱水等表现;18例曾出现肾上腺危象;8例有明确家族史。15例达到青春发育年龄的患儿中,8例(53.3%)伴性发育不良。DAX1基因检测共发现8种突变,包括1种错义、6种移码和1种无义突变;其中6种(c.291delC、c.332-333delCT、p.E137X、c.605delG、c.731delG和c.838delG)为新发现突变,余为已报道过的突变:2例为p.L262P(表兄弟),1例为c.652-653delCA;未发现SF1基因突变存在。DAX1基因突变率为40%(10/25),伴性发育不良患儿突变率为62.5%(5/8),有明确家族史患儿DAX1基因突变率为100%(8/8);DAX1基因突变患儿的发病年龄不同,...

荧光定量PCR检测牛性别相关基因DAX1表达的标准质粒和标准曲线的构建

本研究根据GenBank中登录的剂量敏感的性别反转-先天性肾上腺发育不良基因1(dosage-sensitive sex reversal,adrenal hypoplasia critical region,on chromosome X,gene 1,DAX1)设计引物,构建包含DAX1基因cDNA片段的质粒,作为中国荷斯坦牛DAX1基因mRNA定量检测的标准品,建立了DAX1基因mRNA表达实时荧光定量PCR检测方法。结果表明,该方法特异性好,检测灵敏度达102拷贝,线性范围为102～106拷贝,阈值循环数(Ct)与PCR体系中起始模板量的对数值间有着良好的线性关系(r=0.99975),扩增效率高(E=100%),可以作为检测牛DAX1基因mRNA定量检测方法。

基于MIDAS的DAX网络发布技术在油田WebGIS中的应用研究

提出了基于 MIDAS的 DAX网络发布技术在Web GIS中的设计方法。该方法在一个共享的中间层上封装了商业规则 ,集中的实现了应用服务器所要实现的功能 ,使客户程序将重点放在显示数据和与用户交互上。将这项技术应用于油田中的地质图绘制方面 ,解决了油田中多层分布式异构数据库的访问、管理和地质图件的动态生成问题。研制开发的“基于 Web GIS地质图绘制软件包”在大庆油田推广使用 ,取得了良好的效果。

Gamma generalized linear model to investigate the effects of climate variables on the area burned by forest fire in northeast China

The purpose of this study was to determine a suitable model for investigating the effects of climate factors on the area burned by forest fire in the Tahe forest region, Daxing＇an Mountains, in northeast China. The response variables were the area burned by lightning- caused fire, human-caused fire, and total burned area. The predictor variables were nine climate variables collected from the local weather station. Three regression models were utilized, including multiple linear regression, log- linear model （log-transformation on both response and predictor variables）, and gamma-generalized linear model. The goodness-of-fit of the models were compared based on model fitting statistics such as R2, AIC, and RMSE. The results revealed that the gamma-generalized linear model was generally superior to both multiple linear regressionmodel and log-linear model for fitting the fire data. Further, the best models were selected based on the criteria that the climate variables were statistically significant at at = 0.05. The gamma best models indicated that maximum wind speed, precipitation, and days that rainfall greater than 0.1 mm had significant impacts on the area burned by the lightning-caused fire, while the mean temperature and minimum relative humidity were the .main drivers of the burned area caused by human activities. Overall, the total burned area by forest fire was significantly influenced by days that rainfall greater than 0.1 mm and minimum rela- tive humidity, indicating that the moisture condition of forest stands determine the burned area by forest fire.

Characteristics and tectonic setting of volcanic rocks in Early Cretaceous Baiyingaolao Formation of Keyouzhongqi area,Inner Mongolia

The authors studied zircon LA-ICP-MS U-Pb dating,the zircon Hf isotope and geochemistry of acidic volcanic rocks in Baiyingaolao Formation of Keyouzhongqi area,Inner Mongolia,and discussed the chronology,source region and tectonic setting of the volcanic rocks in the studied area. The clear oscillatory zoning of zircons indicates a typical magmatic origin,and the results of dating show that the volcanic rocks of Baiyingaolao Formation were formed in Early Cretaceous( 121. 5 ± 1. 0 Ma). The features of major and trace elements show that the rocks are alkali-rich,poor in calcium and magnesium with enrichment in LILEs like Th,U,K and Gd and depletion in HFSEs,e. g. Nb,Ta,Sr and Ti. The fact implies that they were the products of partial melting of the crust. εHf( t) =( +6.30--+9.06) and TDM2= 600--835 Ma,suggest the magma originated from partial melting of the young crust. Combined with the evolution of regional tectonic structure,the authors conclude that the acidic volcanic rocks of Baiyingaolao Formation may be formed under the extensional environment related to the subduction of Paleo-Pacific Plate.

硫代基夫碱叠氮基糖原料中间体的合成

利用亚硝酸盐介导的Lattrell-Dax羟基翻转反应,合成了硫代基夫碱的叠氮基糖原料3,并探讨了不同邻位保护基对翻转反应的影响.结果表明:邻位羟基用三苯甲基(Tr)保护,化合物可以成功实现Lat-trell-Dax羟基翻转反应,得到单一构型产物.