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91.
对明清江淮西部地区的旱涝史料进行梳理,对逐年州县旱涝灾害资料等级进行量化处理,并通过计算旱涝平均等级值和10年滑动平均值,重建1450—1911年该区域的干湿变化时间序列。结果发现,该区1450—1911年间共出现6个干湿阶段: 1450—1490年,以轻度干旱为主;1491—1545年,旱涝灾害频发,干湿波动较为明显;1546—1625年,旱涝灾害少发,干湿比较平稳;1626—1710年,以中度干旱为主,极端干旱事件发生频率显著增加;1711—1860年,气候湿润;1861—1911年,干湿波动偏湿润。不同的干湿阶段对江淮西部的湖泊也造成了一定的影响,干旱时期,湖盆积水减少,湖周萎缩;湿润时期,降雨增加,湖泊的蓄水量增加。  相似文献   
92.
“北五省”与“南五省”两词在清代史料中偶有记载,关注者寥寥,少有专门研究。“北五省”当源自“北皿”,“南五省”则来自“南皿”,北皿、南皿所辖省份分别于康熙年间、乾隆六年的最终定型,为“北五省”“南五省”两词在官修史料之出现提供制度依托。两词因科举而生,亦因之而废。随着晚清废科举,南北分闱不复存在,“北五省”与“南五省”亦逐渐成为历史名词。  相似文献   
93.
广东五邑地区以潭江流域为中心,是一个相对独立的地理单元,但该地的政区边界却打破了自然山川的界限。从明代到清初顺治年间,为了应对以民变为首的地方政治危机,朝廷先后在潭江流域设置了恩平、新宁、开平三县。这些县级政区的边界大致与潭江流域的地理分界线重合,地理单元的独立性开始作用于政区划界中。清代雍乾年间,形成了新会、鹤山、新宁、开平、恩平五县分治潭江流域的格局。同时,随着新会县核心政区地位的巩固,流域内各县整合为一个统县政区的倾向开始加强,为后世潭江流域的政区整合奠定基础。明清时期潭江流域的政区变迁体现了地理环境和地方政治局势在政区格局形成过程中的根本性作用。  相似文献   
94.
L. Jiang  W. Pan  C. Cai  L. Jia  L. Pan  T. Wang  H. Li  S. Chen  Y. Chen 《Geofluids》2015,15(3):483-498
Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ13C, δ18O, δ34S, and 87Sr/86Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), 87Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also 87Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ13C, δ18O, and 87Sr/86Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of 12C‐rich (δ13C as low as ?13.8‰) calcite and 34S‐rich (δ34S values from 21.4‰ to 29.7‰) H2S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration.  相似文献   
95.
Intercontinental exchanges between communities living in different parts of Eurasia during the late prehistoric period have become increasingly popular as a topic of archaeological research. The Qijia culture, found in northwest China, is one of the key archaeological cultures that can shed light on trans‐Eurasian exchange because a variety of imports are found in this cultural context. These imports include new cereals and animals, which suggest that human diets may also have changed compared with previous periods. To understand human and animal diets of the Qijia culture, carbon and nitrogen isotope ratios from human and animal skeletal remains were analysed from the type site of the Qijia culture at Qijiaping. The results demonstrate that human diet at the site mainly consisted of millet and animals fed on millet. C3 cereals, such as wheat and barley, did not contribute significantly to human diet, and no isotopic differences were found between adult and subadult diets. Furthermore, three outlying human results raise the possibility of exogenous individuals, perhaps in relation to the parallel movement of animals, crops and goods. This study provides human and animal dietary information for evaluating the nature of exchange and diffusion in eastern Eurasia at this time. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
96.
文章从中国方志史的角度,考察苏州早期府县志在方志史上的地位。苏州是地方志的发源地之一,汉代《越绝书》是中国最早的方志之一。自汉至北宋千余年间,地方志曾以地记、图经等名称和形式长期流行,现存最有名的地记当推唐代陆广微的《吴地记》。宋代,朱长文的《吴郡图经续记》为现存图经实例,范成大的《吴郡志》为首部体例完备的方志定型之作,宋代昆山《玉峰志》首创"凡例"之先例。《至正昆山郡志》和《至正重修琴川志》为两部元代志书的代表作。明代,《嘉靖昆山县志》《弘治太仓州志》堪称州县志书的代表作,卢熊的《洪武苏州府志》和王鏊的《正德姑苏志》为两部明代善本府志。  相似文献   
97.
清道光至同治年间,广西人黃金韶曾长期在江苏为官,先后担任常熟、昭文知县,海州直隶州知州,通州直隶州知州,苏州知府,亲历了在常熟任上督剿受太平军影响的土匪,在海州任上堵截捻军、修复凤凰城,在通州任上镇压响应太平天国的军山农民起义,见证了江苏地方官府对太平天国运动的应对,折射了这个时代的重大社会变化。  相似文献   
98.
陈佳臻 《文献》2020,(3):98-107
元末熊梦祥所撰《析津志》(现仅存辑佚本)的"名宦"部分,从木华黎到刘因等47人的记载,是从《元朝名臣事略》中辑录而得,二者之间存在史源关系。确立了史源关系后,进一步梳理其中的内容,发现《析津志》和《元朝名臣事略》对元初中书官员刘肃的官职记载亦有误,应为"左三部尚书"而非"右三部尚书"。深入考察后进一步发现,《元史·百官志》对元初左右三部设置时间的记载亦有误,应为中统二年,而非中统元年。  相似文献   
99.
盛世才治新时期,新疆局势渐趋稳定后,他效仿中共基层民主建政做法,使新疆基层政权革新初步凸显中共政治民主化色彩。在县级政权,盛世才效仿中共民主集中制原则,设置县政务委员会,民主议决与执行;在县级以下政权建设中推行区村制、民主选举区村长、实施村代表会制。通过借鉴中共基层民主建政经验,盛世才不仅首次健全了新疆基层政权体系,而且率先引入了中共政治民主化的措施,这也在一定程度上推动了当时新疆各项事业的发展。  相似文献   
100.
Establishing stable cropping systems was vital in antiquity, assuring certain yields and enabling ancient people to settle, thus possibly causing various modern food habits and culture to form around the world, especially in cereal-cultivation-dominated countries. China, one of the most famous ancient agricultural countries, has a long history of rice planting, and the fire-irrigation paddy cultivation system is prevalent in the lower Yangtze region, which is considered a rice domestication center. However, its origin and cultivation pattern remain unclear. We studied a famous agricultural vestige, the Chuodun site, involved in rice planting in the lower Yangtze River Delta in eastern China, during the Neolithic Age. Clear evidence from archaeology, paleobiology, pedology and biogeochemistry suggest both that the rice fire-irrigation cultivation system formed during the Neolithic Age and that ancient peoples lived there steadily. Under this extensive cultivation system, soil structures and properties changed significantly; in particular, it left more black carbon in the soil and increased the organic carbon soil stability, which can be used to reconstruct prehistoric environments. Meanwhile, the prevalent fire-irrigation paddy cultivation system used by farmers in this area, though for a different purpose than ancient people, may be inherited from the Neolithic Age.  相似文献   
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