《味水轩日记》所反映长江下游地区1609—1616年间气候冷暖分析

虽然明清时期我国气候总体呈现出寒冷的特征,但其间气候并不是一成不变的,而是呈现出多次冷暖波动的格局。通过对高分辨率资料《味水轩日记》中降雪率、初终雪日期、河流初冰日期、红梅始花日期、初雷日期以及一些感应记录等证据进行分析,表明1609-1616年间长江下游地区的冬半年气温较为温暖,略微高于现代(1951-1980年)气温。这对于分析10年尺度上气候变化,了解明代气候及变化的特征具有重要意义。     

Early Cretaceous chelids from Lightning Ridge,New South Wales

Fragments of plastron and vertebrae from the Griman Creek Formation (middle Albian) at Lightning Ridge, New South Wales, extend the Australian record for chelid pleurodires back in time by over 50 my. Contemporaneous with the oldest known occurrences of chelids in Patagonia, this record indicates that during globally warm intervals, pleurodire distribution included high palaeolatitude locations. Although referred to Chelidae, the material shows no characters to enable more detailed taxonomic assessment and it is unclear whether known genera are represented. The diverse and prolonged history of chelids in South America and Australia indicates that the basal eupleurodiran divergence occurred deep in the Jurassic.     

Ecological Contingency Accounts for Earliest Seagoing in the Western Pacific Ocean

Seagoing at 1 mya to Flores, and sea gaps of >50 km crossed by 47 kya to Sahul, are evidence of earlier maritime migration in the western Pacific than anywhere else. Current opinion attributes the latter to the influence of anatomically modern human cultural complexity on seagoing technology and practice, together with the impetus of serial resource depression. It is argued here that seagoing was unusually advantaged in the western Pacific by a fortuitous conjunction of the warmest seas with a ready availability of large-diameter bamboo that occurred as natural rafts, and which could also be constructed into rafts large enough to transport viable colonizing groups from island to island across Wallacea to Sahul. The geography of Wallacea allowed migration solely by drifting, and exploratory landscape learning might have produced landfalls on Sahul sooner than is implied by subsistence forcing of mobility. Seagoing by drifting raft was much harder from Sahul to the east because of the virtual absence of large-diameter bamboo and longer distance to fewer or small islands; colonization occurred much later.     

海洋在中国地缘政治中的作用

海洋具有与日俱增的地缘政治价值。中国海域拥有突出的地缘战略意义。维护海权是中华民族的一项长期任务。     

17世纪初全球贸易在东亚海域的形成与发展

17世纪初,世界贸易形势发生了巨大变化,东来的欧洲殖民者为贩运中国的生丝和丝织品,在东亚海域展开了激烈的商业竞争,于是在东亚海域形成了全球贸易。而此时正值明朝政府在福建漳州月港开放海禁,准许私人出洋贸易,因此大量的中国海商涌向海外,在与欧洲殖民者激烈的商业竞争中,他们以敏锐的商业头脑和强烈的竞争意识取得了成功,使世界各地的白银源源不断地流入中国,使中国成为当时东亚海域的贸易中心。     

The use of radiocarbon-derived ΔC as a paleoclimate indicator: applications in the Lower Alentejo of Portugal

Values of δ¹³C are frequently reported with radiocarbon dates from organic materials. In C₃ plants δ¹³C values have been linked to changes in water use efficiency as a response to arid conditions. By calculating ¹³C discrimination (Δ¹³C) from ¹³C isotopic composition (δ¹³C), archaeologists can gain potentially valuable inference into past climate conditions. Values of Δ¹³C reflect the process of discrimination against heavier ¹³C isotopes of carbon by comparing the δ¹³C of samples to that of the atmosphere, and can be calculated when records of atmospheric δ¹³CO₂ are available. The present study examines a 1300 year history of radiocarbon-derived Δ¹³C from the Lower Alentejo of Portugal using charcoal recovered from excavations of a series of medieval habitation sites in the study area. To calculate Δ¹³C, the posterior means generated from Bayesian change-point analysis of δ¹³CO₂ records were used. Archaeological data were then compared to contemporary ecological studies of Δ¹³C of the same taxa against instrumental records of climate. Values of Δ¹³C fell within mean ranges for the taxa through a period of population growth between the 7th and 10th centuries AD. During the height of the Medieval Warm Period in the 11th century AD Δ¹³C values frequently fell to low levels associated with arid conditions. At this time environmental degradation and erosion were documented. Values of Δ¹³C increased for a brief period in the early 12th century AD before the rural Lower Alentejo was largely abandoned for nearly two centuries. Another period of aridity occurred in the 16th and 17th centuries AD. Radiocarbon-derived Δ¹³C is a potentially useful paleoclimate proxy for archaeologists provided that results can be paired with observed Δ¹³C variation in studies that pair these data with instrumental climate records.     

中国的海疆与我国海洋地缘政治战略

根据中国领海与毗连区制度以及联合国海洋法公约,我国的领海及海洋国土的面积为300万km²。鸦片战争历史上不平等条约的签订,我国海疆与海权的丧失。文中还提出了90年代及21世纪我国海洋地缘政治战略。     

胡锦涛主席访日与当代中日关系

2006年10月安倍首相访华以来,中日关系出现了回暖的迹象。2008年5月6日至10日,胡锦涛主席的“暖春之旅”,为进一步改善中日关系提供了良好的契机。为扭转两国关系不断下滑的趋势,中日双方对这次访问都做了大量的准备工作。此次访问取得了一系列成果,本文解读了2008年5月7日签署的中日关系的第四个政治性文件,最后分析了这次访问对中日关系的影响。     

《海录》作者、版本、内容新论

《海录》是记述当时海外邻近国际航线的各国、各地区、各城市见闻的作。《海录》对南中国海岛屿、航线的记述,对研究19世纪初中国南海海疆具有重要价值。《海录》是清代记述世界各大洲、各国、各地状况最多最全的作之一,是清代最早记述西方工业明的作之一,对近代以林则徐、魏源为代表的思想家产生过重要影响。