20世纪20年代以来的东北少数民族村寨研究

对20世纪20年代乡村社区研究兴起以来涉及到东北地区少数民族村寨的学术活动和研究成果进行了简单梳理,认为东北地区少数民族村寨的研究过程可分为三个阶段,分别是20世纪20年代至40年代的起步阶段,50年代至70年代的发展阶段以及80年代至今的繁荣阶段。在论述各阶段研究特点的基础上,提出东北地区少数民族村寨的后续研究需要研究者有效兼顾民族志书写和理论剖析两个方面,从而实现对研究对象更为全面、客观、理性的认识和探究。     

长白山采集的中国东北新记录苔藓植物

在对中国和加拿大苔藓学者联合于中国东北最高的长白山采集的2千余份标本鉴定的基础上。认定有苔藓植物59科，152属，300种。报道了中国大陆新记录1属－小曲柄藓属（Campylostelium）。中国东北新记录2属－直蓑衣藓属（Macrocoma）和同叶藓属（Isopterygium）。中国东北新记录5种－褶叶裂叶苔（Lophozia incisa）。假狗牙藓（Cynodontium fallax）。细枝牛毛藓（Ditrichum gracile）。散叶牛毛藓（Ditrichum divarcatum）和细叶棉藓（Plagiothecium latebricola）。     

Compositions of aliphatic des-A-triterpenes in the Hani peat deposit,Northeast China and its biological significance

Aliphatic des-A-triterpenes, the degradation products of pentacyclic triterpenes have been tentatively assigned in samples taken from a 963-cm-thick peat sequence from the Hani region of Northeast China using gas chromatography-mass spectrometry (GC-MS) in order to understand and identify these des-A-triterpenes response to climate and ecology. The study indicates that aliphatic des-A-triterpenes are abundant in the Hani peat bog. The high relative abundance of the total des-A-triterpenes mainly occurs at the Holocene periods and is corresponding to the low sedimentation rate. The mechanism of des-A-triterpenes accumulation is not consistent with the previous studies. It is proposed that the biological community is also one influence factor. The obvious stage variations of the total des-A-triterpenes in the whole sequence reveal the different biological (microbes and plants) processes and responses, possibly revealing the four large replacements of biological community and functional composition in the swamp environment over the 16000 cal a BP. The low total des-A-triterpenes values occur at about 10200, 8700, 7700, 6600, 4480–3940 and 3040 cal a BP, reflecting the multiple millennial micro-environment oscillations under the macro-environment of the swamp during the Holocene. The ratios of diene and monoene des-A-triterpenes (DT/MT), des-A-lupane and diene and monoene des-A-triterpenes (DL/(DT+MT)), ratios of individual compounds exhibit vertical opposite to the total des-A-triterpenes. Namely, these ratios are high during the last deglaciation and late Holocene whereas they are low at other periods, indicating different compounds have different responses to micro-environment and microbial activities. This study discusses the diversity of biological community and biological functional composition response to micro-environment, which not only provides the complement in Northeast China, but also bears important fundamental information for the implication to ecological environment in the future.     

沁东北15号煤显微组分对微裂隙的控制作用

煤层显微组分与微裂隙二元关系研究对煤层气开采具有潜在价值.通过对沁东北太原组15号煤宏观、电镜、物性等方面资料进行综合分析,对煤储层显微组分和微裂隙之间二元机理进行阐述,结果表明,基质有机显微组分可以产生张性裂隙和压性裂隙,而镜质组中的张性裂隙对煤层气扩散作用较大,惰质组中内生裂隙不太发育.该区渗透率呈现低渗——特低渗的原因主要是割理被脉状方解石填充以及粘土矿物的充填.     

俄日北方四岛纠纷及其对东北亚局势的影响

北方四岛在历史上曾多次易主。二战期间,苏联根据《波茨坦公告》重新占领了北方四岛,并将其划为自己的版图。2010年11月,俄罗斯总统梅德韦杰夫视察了国后岛,引发新一轮俄日岛屿纠纷。从目前形势来看,俄罗斯在岛屿争端中占据有利的位置,不会将北方四岛交还日本。俄日岛屿纠纷的彻底解决,还有很长的一段路要走。俄日岛屿争端将影响大国关系的调整,加剧东北亚紧张局势,导致地区内国际力量对比与战略格局的重新组合。     

宁州之设置与南中郡县制的反复——魏晋南北朝时期滇东北政区制度的演变

公元280年晋灭东吴后全国分为十九州,宁州居其一。此后300年间,国家陷于分裂,朝代更替频繁,政区变化无常;宁州郡县在中原王朝的军事监护与地方大姓的武力割据之间反复震荡;两汉及蜀国400年苦心经营建立的郡县制,终因豪强坐大而崩溃,郡县名号虽载于版籍,而行政制度无所施行。曾是经济繁荣、文化先进,号称＂宁州冠冕＂的朱提地区,社会发展也因此跌入低谷,历经了千年之久的停滞,直至明清时期才逐渐复苏。     

川东北下三叠统飞仙关组裂缝测井识别与反演

裂缝性碳酸盐岩储层非均质性较强,单一应用某种测井资料对裂缝进行识别和评价往往满足不了精细描述的需要。经岩心观察与常规测井、成像测井资料对比,建立裂缝在测井资料上的识别特征和识别方法。利用深浅侧向电阻率(RLLD、RLLS)、补偿声波(AC)、补偿中子(CNL)、补偿密度(DEN)、自然伽马(GR)、无铀伽马(KTh)等测井响应特征与微电阻率扫描成像测井(FMI)图像特征进行裂缝识别,计算裂缝几何参数,评价裂缝有效性和发育程度,经实际对比应用,具有较好的效果。     

东北亚多边安全机制构建中的美国因素——以六方会谈机制为例

虽然现阶段六方会谈因朝鲜的退出陷入困境,但它涵盖了东北亚地区内的主要安全力量,对东北亚多边安全机制的构建具有重要意义。东北亚安全机制构建中的美国因素尤为重要,这是由美国作为世界唯一超级大国的实力决定的。这种因素有其消极的一面。东北亚要建成多边安全机制,还需要各方作出更大努力,如加强制度化建设与扩大议题,并促使美国在机制中有个适当的定位。     

张学良东北易帜原因新探——基于张学良口述史料的研究

东北易帜是张学良亲掌东北权柄后作出的一项重大抉择。张学良本人的口述史料清晰地再现其东北易帜时的心理活动,从崭新的角度揭示了其东北易帜的原因：顺应民族自救、国家统一的时代主流;能力远不及父亲,应付不了当时复杂的局面,主要是应付不了日本人的纠缠;渴望祖国统一,从无思求地盘之心;日本炸死父亲,国仇家恨加重了易帜的决心。     

Surface pollen assemblages of human-disturbed vegetation and their relationship with vegetation and climate in Northeast China

Pollen assemblages of 53 surface pollen samples from farmlands and wastelands in Northeast China were analyzed. Tree pollen percentages were usually higher than 30%, with Pinus (26.9%), Quercus (0.9%), Betula (0.9%) and Populus (0.7%) as the major types, and herb pollen percentages were usually higher than 50%, with weedy Poaceae (8.7%), Chenopodiaceae (7.1%), Artemisia (1.9%) and Compositae (3.5%) as the major taxa. Thus, the pollen assemblages were consistent with the regional vegetation compositions. However, there were differences in pollen assemblages among regions, especially among different geomorphological units. For example, in the mountains, there were more types of tree pollen and higher total percentages (average 42%) than in other areas, while cereal pollen percentages were lowest (11.2%). In the hills and high plains, herbs made up more than 60% of the pollens, with cereals (average 53.6%) the dominant type. In the low plains, pollen types were similar to those in the hills and high plains, but total pollen concentrations and the proportion of Concentricystes were much higher, while cereal pollen percentages were slightly lower (average 41.6%). Pollen assemblages in different land use types also differed. For example, in farmland, cereal pollen percentages were more than 40% and Chenopodiaceae was usually less than 2.5%, while in wasteland, weedy Poaceae was usually less than 10% and Chenopodiaceae was usually higher than 25%. Total pollen concentrations in farmland (average 3909 grains/g) were much lower than in wasteland (average 15074 grains/g). Redundancy analysis revealed that pollen assemblages were significantly negatively correlated with mean annual temperature (-0.73) and July mean temperature (-0.81) and significantly positively correlated with mean annual precipitation (0.48), indicating that pollen assemblages in the artificial or human-disturbed vegetation reflect regional climate well. Comparison of pollen assemblages in different areas of northern China showed that pollen concentrations reflect the intensities of human impact to some degree. For example, pollen concentrations decrease as human impacts increase in intensity. The cereal pollen proportions in farmland differed by area. In Northeast China, cereal pollen proportions were distinctly higher than in most other areas of northern China, suggesting differences in planting habits and climate.