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61.
The extent to which North Atlantic Holocene climatic perturbations influenced past human societies is an area of considerable uncertainty and fierce debate. Ireland is ideally placed to help resolve this issue, being occupied for over 9000 yr and located on the eastern Atlantic seaboard, a region dominated by westerly airflow. Irish bog and lake tree populations provide unambiguous evidence of major shifts in surface moisture through the Holocene similar to cycles recorded in the marine realm of the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. To test for human response to these cycles we summed the probabilities of 465 radiocarbon ages obtained from Irish archaeological contexts and observe enhanced archaeological visibility during periods of sustained wet conditions. These results suggest either increasing density of human populations in key, often defensive locations, and/or the development of subsistence strategies to overcome changing conditions, the latter recently proposed as a significant factor in avoiding societal collapse. Regardless, we demonstrate environmental change is a significantly more important factor in influencing human activity in the landscape than has hitherto been acknowledged.  相似文献   
62.
The Amazon region has long been a place of economic booms and busts. Much attention in the historical literature on Amazonia has focused on the largest and most famous regional economic boom, the Rubber Boom, a period of sustained economic prosperity for some from 1860 to 1920. Other ‘booms’ have occurred in the region as well and this paper describes and discusses one of those others. The paper demonstrates how an export economy in a global periphery (coffee in Brazil) affected economic development in a periphery of that same country and makes a methodological contribution by demonstrating how ethnographic research can contribute to an understanding of a historical period when the paper trail is weak.Jute, a fiber crop, dominated agricultural production along the Amazon River floodplain in the reach between Manaus and Santarém, Brazil, from the late 1930s until the early 1990s. The crop was introduced to the region by Japanese immigrants in order to supply the demand for jute sacking in the south of Brazil where such sacks were used to package commodities, especially coffee. Local smallholder cultivators grew and processed jute, production being mediated initially through Japanese middlemen, later by Brazilians. Poor fiber quality, several external shocks, including the removal of tariffs on imported jute, and especially changes in commodity packaging such as bulk handling and the use of synthetic sacks instead of jute sacks for the transport of coffee beans, the Amazonian jute market collapsed in the early 1990s. Despite its collapse, the legacy of the boom is still evident in the physical and social landscapes in the region.  相似文献   
63.
The marine trophic levels targeted during Swift Creek (AD 300–700) and Savannah (AD 1200–1500) occupations at the Cathead Creek site (9Mc360) and at two sites from the Kings Bay Locality (9CAM171a, 9CAM177), coastal Georgia, USA, differ in a consistent temporal and spatial pattern. Vertebrate and invertebrate remains from these three coastal sites contain similar suites of estuarine animals. However, Swift Creek peoples at these distinct hydrological settings obtained more biomass from fishes and less from molluscs compared to the subsequent Savannah occupants. The two Swift Creek faunal collections are less rich, more diverse, and more equitable than the two subsequent Savannah collections regardless of location. Furthermore, the mean trophic level is higher in the Swift Creek collections compared to the Savannah ones at both locations. These observations apply to both biomass and Minimum Number of Individuals. These differences likely are defining characteristics distinguishing the Swift Creek and the Savannah economies. More research is needed to determine the extent to which these temporal and spatial patterns are attributable to environmental and cultural variables.  相似文献   
64.
经济行为与环境变化:清前期台湾野生鹿消失探析   总被引:3,自引:0,他引:3  
鹿曾经是台湾数量最庞大的野生动物群之一。明末以来,随着台湾贸易交流的活跃,鹿成为大宗出口商品,土著居民由原先捕鹿作为民生用品逐渐发展至为市场服务;清前期大陆移民入台的农业垦殖又破坏了鹿原有的生态环境。人类经济行为引发的环境变化,最终导致了野生鹿在台湾渐趋消失。  相似文献   
65.
气候变迁与商人南下   总被引:2,自引:0,他引:2  
张渭莲 《中原文物》2006,12(1):37-45
自然科学研究成果显示,距今4000年-3500年期间全球气温有过明显下降,这一降温事件对当时人类的活动产生了重大影响。建国前的商人正处于此次气候发生变异的时期,其活动地域的南迁与气候变化紧密相关。  相似文献   
66.
Geomorphological and geoarchaeological studies from the lower Gulf region of southeastern Arabia are increasing our knowledge of hydrological, ecological, and aeolian changes during the Holocene. Preliminary analyses of sediment records from two palaeolakes in the United Arab Emirates are presented, highlighting the potential of these sediment sources for providing high-resolution decadal studies of climate change and landscape evolution over the past 10,000 years. In order to study the society-environment relationship in this marginal region, a framework of environmental change is being developed against which the archaeology of the region can be set.  相似文献   
67.
“杨各庄”等地名的地理分布及其音变的历史意义   总被引:1,自引:0,他引:1  
华北地区及华东地区地名中多见“X各庄”和“X家庄”。该地区中,从西北部到东南部,“X各庄”的比例逐渐增多,而“X家庄”的比例逐渐减少,形成了一个语音渐变的地理连续体。这种特殊现象的形成是由于该地区西北部较频繁地受到北方阿尔泰语系诸语言的影响,而相对来说,东南部则较少受到这种影响。地名中的“各”仍然保留了中古汉语“家”的舌根音塞音声母[k-]。这种明显的地域互补分布表明了北方汉语方言前高元音前面的舌根声母转变为舌面音的力量来自于外部的人文影响,而非内部语言音变。  相似文献   
68.
This paper describes the hitherto unreported occurrence of mid‐Holocene mangrove deposits in the Richmond River estuary, southeastern Australia, thereby providing evidence for changes in the distribution and composition of mangrove communities within a subtropical estuarine system during the Holocene. Stratigraphic, radiocarbon and palynological evidence indicates that widespread development of mangrove communities took place in the upstream reaches of the Richmond River estuary during the period 7000 to 6000 years BP. These communities maintained their habitat through substrate aggradation under the conditions of a moderate sea‐level rise, in contrast to other estuaries within the region, which generally experienced the submergence of intertidal substrates. Mangrove species belonging to the family Rhizophoraceae, most likely Bruguiera gymnorrhiza and Rhizophora stylosa, dominated these communities, in strong contrast to contemporary communities, which are dominated by Avicennia marina. Moreover, these mid‐Holocene communities were located a considerable distance upstream of the contemporary occurrences of Rhizophoraceae species within the estuary. The changes in the spatial distribution and composition of mangrove communities parallel the large‐scale evolution of the estuary driven by sea‐level variation. Shallow, buried Pleistocene terraces probably contributed to the regionally unique aggradational response of the mangrove communities and their substrates to a sea‐level rise during mid‐Holocene times.  相似文献   
69.
20世纪中国的社会转型与社会变革的两种思想和方式   总被引:1,自引:0,他引:1  
在20世纪中国社会转型的过程中,革命与改良(改革)这两种变革思想和方式之间虽然有重大区别,但又是互补的,而且"你中有我,我中有你".两者在不同的历史时期各凸现其主导功能,也会相互转化,不可绝对地厚此薄彼,更不可只肯定一种而否定另一种.事实上,革命与改良是同一部乐曲的"双重变奏",两者的相生相克、相辅相成、交互辉映,共同组成了20世纪中华民族救亡图存、启蒙大众、革故鼎新的历史画卷,共同推进了中国社会的现代化.20世纪最后20多年的改革和发展趋势表明,中国尽管已从根本上摆脱了自我束缚的困扰,但进入新世纪后最需要的是居安思危,力戒盛世意识,增强忧患意识.  相似文献   
70.
魏峻 《南方文物》2008,(1):96-107
粤东地区全新世的考古学文化具有鲜明的地方特色,不同时间的古文化在文化面貌和生计方式上存在着明显差别。本文在分析粤东地区汉以前区域气候波动和海平面升降的基础上,探讨了该地区不同考古学文化聚落形态的特点以及人地之间相互作用的过程。  相似文献   
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