洪泽湖历史洪水分析(1736-1992年)

根据１７３６－１９１１年文献记载的洪泽湖年最高水位及１９１４－１９９２年湖区水文测站的水位,流量资料,进行了长,短序列的入湖洪峰流量及不同时段洪量的频主分析,进而推求出不同重现期的设计入湖洪量和洪水年份相当的重现期,并分析洪水的灾害特征,结果：１）洪泽湖历史上洪水发生频繁,１７８６,１８５１,１９０６年均发生过特大洪水,高堰志桩分别至１６．３,２３．４,１６．１尺。２）１９５３年建库后,湖水位上升     

TEXTUAL RESEARCH OF LONGXI EARTHQUAKE IN 47 BC IN GANSU PROVINCE AND ANALYSIS OF ITS CAUSATIVE STRUCTURE

On the day Wu-wu of the second month in the second year of Chuyuan period in the reign of Emperor Yuan of the western Han Dynasty, that is, April 17, 47 BC, an earthquake occurred near the county seat of Huandao County, Longxi Prefecture. This earthquake caused serious damages to the city wall, government office buildings and civilian houses in the Huandao county seat, many people died, landslides, ground fracturing and spring gushing, etc. occurred. On the basis of textual research on the historical earthquake data and the field investigation, we affirm that the ancient Huandao county seat locates at the new Wangjia Village of Santai, southeast of Wenfeng Town in Longxi County at present. The ancient Huandao county seat is the most seriously damaged area according to the historical earthquake data, so it should be in the meizoseismal area of this earthquake. The epicenter intensity of this earthquake is about 9~10 degrees, and the magnitude of this earthquake is estimated to be about 7. Considering the intensities of other towns damaged during this earthquake, we draw the isoseismal lines of this earthquake, with its major axis directed NNW. The direction of the major axis of the isoseismal lines and the location of the epicenter are approximately consistent with the strike of the western segment of the Gangu-Wushan secondary fault on the northern margin of western Qinling fault zone. This fault segment has clear evidences of new activity during late Holocene, which are characterized by left-lateral strike-slip faulting with normal components; the fault dips NE and faulted the T₁-T₂ pluvial and alluvial terraces. Up to now, there are some surface deformation traces, such as deeply-incised seismic fault grooves, densely developed structural tensional fractures in the loess stratum, landslides and a series of beaded dolines etc. Combining the results of relocation of small to moderate earthquakes in the research area and comprehensive analysis on their distribution features in plane and profile, we get the results that the causative structure of the 47 BC Longxi earthquake is the western segment of Gangu-Wushan secondary fault on the northern margin of western Qinling fault zone. This fault zone is an important active block boundary fault in the eastern margin of Tibeten block, and has the tectonic condition to generate M ≥ 7 large earthquakes in the past and in the future.     

云梦泽与荆江三角洲的历史变迁

本文通过对大量地质地貌、考古和文史资料的综合考证与分析,讨论了(1)云梦泽的形成、范围与兴衰历史;(2)荆江三角洲变迁的过程、阶段与特征;(3)荆江三角洲与洪涝灾害;(4)江湖历史变迁与问题思考等。     

LATE QUATERNARY TECTONIC DEFORMATION AROUND THE HUJIATAI ANTICLINE ALONG THE EAST SEGMENT OF THE FODONGMIAO-HONGYAZI FAULT,NORTHERN QILIAN SHAN: AN INSIGHT ON THE SEISMOGENIC PATTERN OF 1609 HONGYAZI M7 1/4 EARTHQUAKE

The Fodongmiao-Hongyazi Fault (FHF)is one of the most active faults of the northern Qilian thrust fault zone. The 1609 Hongyazi M7 1/4 earthquake occurred on the east segment of the FHF, an area with a complex geometry at the Mayinghe River site. The seismogenic pattern of this earthquake revealed by complex surface ruptures remains unclear. In this paper, we focus on active tectonic deformation around the Hujiatai anticline (HA)in the Mayinghe River site. Combining with topographic survey via dGPS across deformed terraces and alluvial fans, a field survey of the geological section across the HA, the characteristics of the active fold and several sub-faults were constrained. Meanwhile, combined with the seismic reflection profiles passing through the anticline, the correspondence relationship between surface expressions of this tectonic and the deep structure was discussed. According to our research, the HA is a result of northward propagation of the range-front thrust fault F₁. At the same time, a thrust fault F₂ with dextral strike-slip motion and a thrust fault F₄ were formed on the east side and north side of the HA, respectively. These two active faults accommodated local deformation. Trench results and ¹⁴C dating reveal that the 1609 Hongyazi M7 1/4 earthquake ruptured the T₁ terrace in the Huangcaoba site. Combined with previous field investigations and literature about the 1609 Hongyazi earthquake, we suggest that this earthquake occurred on the range-front fault F₁, and the depth of the hypocenter may be about 8~22km.     

The central European flood of 1572 and its local-scale effects as revealed by a damage inventory

ABSTRACT

A cyclone in July 1572 caused a catastrophic flood in the catchments of the Upper Danube and Vltava rivers. A previously unpublished inventory dating to 1574 enabled local-scale insight into the effects of the cyclone. The degree of destruction was inventoried for 355 subjects of the Benedictine Abbey of Admont, Austria. The location of 150 damaged buildings was possible due to registers, cadastres and other geographical sources. Spatial analysis revealed that most of the properties damaged were located near watercourses at alluvial fans. A significantly greater amount of damage was revealed for properties, which would be nowadays located in moderate- and high-risk hazard zones. Only 18.7% of the properties damaged in 1572 were located inside modern hazard zones. By using methodological approaches of history, environmental history and geography, we show that it is possible at local scale to reconstruct the spatial pattern, magnitude and intensity of a cyclone ca. 450 years after the event.     

Seismic isolation: Early history

Seismic isolation or “aseismic base isolation” is an earthquake protection strategy that aims to uncouple the motion of a structure from the ground shaking and thereby reduce structural forces. A most effective and successful seismic protection technology, seismic isolation, is by now a mature and viable alternative to traditional capacity design and has been implemented in numerous bridges, buildings, and other special structures worldwide. This paper records the origins and early developments (up to the early 1990s) of seismic isolation.     

基于地方志的1736-1911年华北秋粮丰歉指数序列重建及其与气候变化的关系

粮食作物的收成丰歉与气候要素的关联是研究历史时期气候变化社会影响的重要切入点。利用清代地方志中的收成丰歉记录,以语义差异法对收成等级进行区分,重建了1736-1911年华北地区秋粮丰收和歉收指数序列,定量分析收成变化特征及其与同期温度和降水变化的关系,并对比以往常用的官方收成分数奏报记录,探讨地方志资料在重建历史粮食收成变化中的优势和不足。结果表明：① 地方志中的歉收记录相比丰收记录更为可靠,重建的歉收指数序列可在相当程度上描述总体收成的变化,就宏观趋势而言,19世纪歉收风险相比18世纪显著增加。② 歉收指数序列与10年、5年尺度的温度变化均呈显著负相关关系,反映气候转冷可显著提升歉收风险;在年际尺度上,歉收指数序列与降水呈显著负相关,与旱灾指数序列的相关系数则达到0.71（p < 0.001）,体现出极端旱灾对于华北粮食收成的严重威胁。③ 地方志中的收成记录虽在量化精度上不如奏报,但其歉收记录对于极端减产年份的反映更为准确,两者在实际应用中存在一定的互补性。以上结论有助于改进利用历史文献资料研究过去气候变化影响的技术手段,并深化气候变化对过去农业生产系统影响规律的科学认识。     

明代省域耕地数量重建及时空特征分析

基于明代册载田亩、屯田和人口数据,以及相关赋役制度和土地制度等史料,考察了明代册载田亩和屯田数据的合理性,辨识了导致明代册载数据失实的主要因素,重建了明代典型时点省域耕地面积。结果表明：① 册籍讹误、官民田和卫所屯田的分类统计及山、塘、湖、荡等非耕地的登册起科,是导致洪武和万历年间册载数据失实的主要原因。② 洪武年间河南和湖广册载田亩数据人均耕地面积畸高,其原因为“册籍讹误”,订正后的数值分别为41万今亩和18万今亩;该时期研究区阙载的屯田总额约为5620万今亩。③ 非耕地的登册起科主要出现在南方地区,且洪武和万历年间浙江、南直隶、江西、湖广等省的册载田土数据中非耕地占比分别为24.7%、23.3%、4.4%、3.7%和28.9%、16.2%、19.2%、11.6%。④ 洪武二十六年（1393年）至万历十一年（1583年）,研究区耕地总量由49 550万今亩增至75 430万今亩;省域土地垦殖变化呈现明显的区域差异,河南和山东两省垦殖率增量超过15个百分点,湖广和四川超过3个百分点,而其余各省增量低于1个百分点。区域历史时期土地利用/覆被变化数据重建,不仅是区域生态环境效应模拟的客观需求,也可为充实和完善全球数据集提供参考。     

清末以来洞庭湖区通江湖泊的时空演变

本文利用清光绪22年以来17个时段的多种历史地图和航天航空遥感数据,采用遥感解译、数据统计分析与历史对比方法,分析清末以来洞庭湖区通江湖泊面积的时序变化,探究空间演变特征。结合水利部门发布的典型年份监测数据,检验了遥感获取的湖泊面积精度,误差仅为0.62%。结果显示：洞庭湖通江湖泊面积从1896年的5216.37 km²减少到2019年的2702.74 km²,萎缩率为48.19%。1949年前的53年为明显萎缩期,年均萎缩15.66 km²;20世纪50年代为陡崖式萎缩期,年均萎缩139.05 km²;20世纪60—70年代为快速萎缩期,年均萎缩21.66 km²;1980年以来为基本稳定期,年均萎缩0.13 km²,面积仅减少了5.10 km²。就具体湖泊而言,东洞庭湖是各通江湖泊中面积萎缩最大的湖泊,减幅为922.60 km²;其次是目平湖,减幅为588.05 km²;再次是南洞庭湖,减幅为448.37 km²;七里湖的面积变化很小,但经历了先扩张后萎缩的过程。1998—2002年实施“退田还湖”工程,洞庭湖面积增加了10.50 km²。总体而言,清末以来洞庭湖区通江湖泊的演变主要表现为大通湖的封闭析出、整修南洞庭湖的湖垸置换与南迁、围垦西洞庭湖的局部残存、东洞庭湖的三面合围以及1998年特大洪灾后有限的“退田还湖”。本文为长江流域生态修复和环境保护战略提供了客观资料和技术支撑。     

赤湾验潮站搬迁前后潮位变化特征及其订正

赤湾海洋站是国家海洋局在深圳西部海域唯一的潮汐观测站点,至今已观测30多年。由于地理位置特殊,2008年起该站被选为《中国海平面公报》反映珠江口海平面变化的代表站。2012年10月该站搬至新验潮站,受此影响,其潮位观测序列产生了差异性和不连续性。本文通过计算机编程实现了对海洋站水文气象数据的质量控制。同时,采用赤湾站与邻近验潮站进行对比的方法得出新旧站的潮位差值,初步探讨了搬站前后潮位观测结果的订正方案,并研究其建站以来的历史海平面变化特征。这对确保该站潮位资料的准确性及代表性具有重要意义,同时也为珠江口海域防灾减灾、涉海工程、风暴潮预报等提供了数据支撑。