首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   701篇
  免费   41篇
  2023年   8篇
  2022年   8篇
  2021年   3篇
  2020年   27篇
  2019年   23篇
  2018年   28篇
  2017年   22篇
  2016年   29篇
  2015年   25篇
  2014年   22篇
  2013年   138篇
  2012年   55篇
  2011年   43篇
  2010年   34篇
  2009年   29篇
  2008年   65篇
  2007年   30篇
  2006年   28篇
  2005年   16篇
  2004年   11篇
  2003年   7篇
  2002年   13篇
  2001年   15篇
  2000年   6篇
  1999年   4篇
  1998年   8篇
  1997年   9篇
  1996年   7篇
  1995年   6篇
  1994年   6篇
  1993年   1篇
  1992年   2篇
  1991年   1篇
  1990年   1篇
  1988年   2篇
  1986年   1篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1980年   3篇
  1978年   3篇
排序方式: 共有742条查询结果,搜索用时 15 毫秒
691.
Nationalist visions are often connected with a cult of the land. This article considers some of the cultural‐nationalist ideas linked to the Somerset town of Glastonbury, a prominent New Age centre. It discusses the legacy of British pastoralism as shown in the work of H. V. Morton and Cecil Sharp. It considers the evolution of an English–Celtic tradition, drawing on the legacy of the Arthurian legend, but being re‐formulated in the late twentieth century as a vehicle for New Age conceptions of British society. The article concludes by evaluating the political values inherent in the New Age.  相似文献   
692.
ABSTRACT

South Africa's northern Namaqualand coastal desert is the southern extension of the Namib. Today, this region is semi-desert with patchy subsistence resources and scarce, unpredictable rainfall. Yet this ancient desert landscape possesses residues of human activity stretching back into the Middle Pleistocene, evidenced by heavily weathered surface finds, including handaxes and Victoria West cores. Such old finds in so harsh an environment raise important questions: how do human movements into this area relate to local palaeoenvironmental changes, and how has this relationship changed through time? While no dated Middle Pleistocene sites presently exist to reconstruct the earliest hominin dispersals, several late Pleistocene sites now have chronostratigraphic sequences that can be brought to bear on these questions. This article presents chronological and subsistence-settlement data for one such site, Spitzkloof A Rockshelter in northern Namaqualand's rugged Richtersveld. Humans are shown to have visited the site very sporadically between ~50,000 and 17,000 cal BP. Unlike most of the subcontinent, the most intensive occupations occur during early Marine Isotope Stage 2, when multiple proxies suggest enhanced humidity associated with intensified winter rainfall. We examine these data using the region's better-developed Holocene archaeological record to create predictions about the earliest coastal desert dwellers.  相似文献   
693.
This study focuses on microinclusions of platinum group minerals (PGMs) in gold objects from the South Urals and North Black Sea archaeological sites. We demonstrate for the first time that melting of gold during archaeometallurgical work affects PGM microinclusions. Desquamation of primary PGM microinclusions with 28–55 wt% Os in the melt and their oxidation by hot air microbubbles results in the formation of secondary particles with 1–20 wt% Os around the primary inclusions. We conclude that the composition only of primary PGM microinclusions in ancient gold products is comparable to the composition of those from natural sources.  相似文献   
694.
In semi-arid to arid environments, water is the most constraining resource for agricultural communities. In Southeast Arabia (Sultanate of Oman and United Arab Emirates), the demographic growth and the increase of sites at the beginning of the Iron Age II (1100–600 b.c.) is generally attributed to the development of groundwater harvesting techniques, and more precisely to qanāt technology. While only little is known on the origin of this technology, even less is known about other hydraulic techniques, which could have been used as a complementary source of water. An irrigation system, recently discovered near an Iron Age settlement in the oasis of Masāfī (UAE) was studied thanks to the combination of various methods—archaeology, geoarchaeology/micromorphology, spatial analysis, and chronology—which have allowed us to identify the technological development of small-scale runoff farming and to link this practice to social as well as environmental issues.  相似文献   
695.
Domestic faunal samples from farming sites from southern Africa dating from the Early (~AD 200–900) and Middle (~AD 900–1300) Iron Ages with large faunal samples are typically dominated by sheep/goats (both number of identified specimens and minimum number of individuals for large samples). However, four exceptions to this general pattern from these time periods are Bosutswe, Nqoma (both in Botswana), KwaGandaganda and Mamba (both in KwaZulu-Natal). At these sites, cattle outnumber sheep/goats, which have previously been measured using a Cattle Index. Intensive hunting is investigated at one of these sites, Bosutswe. Using various lines of evidence, including measuring high- vs. low-ranked prey, economic activities, as well as grease extraction and ageing from the most common taxon, plains zebra (Equus quagga), it is suggested that resource depression of wild game likely occurred. This would fit the expectation, based on human behavioural ecology, that as high-ranked game resource diminished over time, more emphasis was placed on cattle herding. The greater emphasis could have influenced descent patterns of people at Bosutswe. By the Late Iron Age (~AD 1300–1820s), cattle dominate most faunal assemblages in southern Africa with large sample sizes, and ethnographic and historical information confirm the central role these animals played in the social, political and economic lives of these farmers.  相似文献   
696.
The Zhokhov site is one of the northern most archaeological sites in the world and a very ancient vestige of occupation of high latitudes by people, indicating that this territory was settled as early as about 8000 years ago. Investigation of the site began in 1989–1990 and then continued in 2000–2005. Here we consider the taphonomy, spatial distribution, species and age- and sex-related composition of the faunal remains from the Zhokhov site. These data allow conclusions regarding the subsistence strategy practiced by Zhokhov inhabitants, including the hunting tactics. This was a peculiar adaptation model based on reindeer and polar bear hunting in a 2:1 ratio. Reindeer hunting was all-seasonal, whereas polar bears were hunted mostly in winters at their dens. Mortality data for reindeer and polar bears depict the yearly subsistence cycle. The Zhokhov site is found to be a base camp occupied year-round with modest summer activities, while wintertime is characterised by intense polar bear hunting. Most reindeer were hunted in the fall. Subsistence strategy of the Zhokhov hunters was largely facilitated by the fact that at the time of occupation Zhokhov Island was still part of the coastal Siberian plain margin.  相似文献   
697.
Due to the global increases in urbanisation rates, urban sprawl has become a worldwide issue. In China, the development of rural areas has been affected by urban expansion and adjustments of metropolitan areas by administrative divisions that have led to losses in agricultural lands and ecosystem services. There is the ‘paradoxical’ desire for governments to promote rural development and protect land resources. Urban fringe sprawl is a prominent issue in the process of rural development. Identifying and measuring sprawl at the urban fringe could assist policymakers to either encourage or discourage this phenomenon. This paper demonstrates use of multidimensional indicators to effectively measure urban fringe sprawl by remote sensing, in addition to demographic and socio‐economic data. Using integrated indicators observed in the recent Chinese development context, urban fringe sprawl was measured comprehensively for Jiangning, a district in the city of Nanjing, China. This study indicates that Jiangning is sprawling rapidly. The results also show that the multidimensional indicator approach could provide decision support to create effective long‐term land‐use planning policies for controlling urban sprawl patterns.  相似文献   
698.
西山古城与中原地区早期城市的起源   总被引:2,自引:0,他引:2  
城市起源是中国古代文明起源研究中的重要课题。随着近年来史前城址考古发掘资料的不断增多,中国早期城市的面貌正逐渐清晰起来。迄今的考古发现与研究已揭示了中原地区早期城市较完整的发展脉络。在中原地区既发现有从龙山时代到战国时期  相似文献   
699.
We show that carbonized fruits and seeds recovered from Middle Stone Age deposits in rock shelters are likely to have been carbonized as part of post-depositional processes. We buried indigenous South African fruits, nuts and seeds at pre-determined depths and distances from the centers of experimental fires. The cold ashes of the hearths and the sand surrounding them were subsequently excavated, using standard archaeological techniques and dry-screening. The fruiting structures from the oxidizing part of the fire were burnt to ashes, whereas those buried in sand under anoxic conditions survived in varying forms. Those buried 5 cm below the center of the fire were carbonized; those buried 10 cm below the center of the fire were dehydrated; and those 5 cm and 10 cm below the surface at the outer edge of the fire were unaffected. Size, moisture or oil content of the original fruit or seed did not appear to influence whether or not carbonization took place. Temperatures recorded 5 cm below the experimental fires suggest that the carbonization occurred at or before a maximum temperature of 328 °C, and also at lower maximum temperatures (152 °C) that were maintained for long periods. Even when the quantities of a particular wood are controlled, open fires may produce variable underground temperatures and the temperatures below ancient hearths would have been equally variable. We suggest that Cyperaceae (sedge) nutlets, the most numerous fruiting structures in the Sibudu Middle Stone Age archaeobotanical assemblage, occur in the shelter as a result of human activity, subsequent burial, and accidental carbonization when hearths were built directly above the buried nutlets.  相似文献   
700.
Stable isotope analyses of modern coastal and salt-marsh plant species (‘salt-loving’ plants or halophytes) have demonstrated that these are significantly enriched in 15N compared to other terrestrial plants. Coastal salt-marshes were far more extensive in the past than they are today. They represented a vast and much-exploited resource in many areas of the UK and north-western Europe and were considered to be prime land for the grazing of animal stock.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号