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41.
熊家冢土遗址保护概述   总被引:1,自引:0,他引:1  
本文介绍了熊家冢墓地的概况以及地质、土壤状况,分析了保护中需要解决的主要问题。通过对殉葬墓和车马坑的综合保护,实现了防止殉葬墓坑、车马坑的崩裂、垮塌和各类遗迹的开裂、塌陷。熊家冢土遗址保护工作的开展,对我国南方地区土遗址保护技术的发展有一定借鉴作用。  相似文献   
42.
Analysis of plant microfossils (phytoliths, pollen, and starch grains) from archaeological and paleoecological sediments in the humid Neotropical forest can provide information on some formerly intractable problems in American paleoethnobotany and archaeology. Each technique has strengths that redress the other's shortcomings, and all three microfossils can be recovered from early sites, securely identified, and dated. Agricultural origins, Pleistocene/ Holocene environmental changes, and the evolution of slash-and-burn agriculture are three important issues that yield substantial results to phytolith, pollen, and starch grain study. Microfossils of a number of domesticates, including maize, manioc, squash, bottle gourd, arrowroot, and leren, have been identified in contexts dating from 9000 to 7000 radiocarbon years B.P. The scope and methodology of traditional paleoethnobotany should be expanded to routinely include microfossil study.  相似文献   
43.
This article presents a comprehensive study of the local soils and historic earthen building materials used in Nako temple complex in Western Himalayas. On-site and laboratory investigations followed a holistic approach to characterize materials and identify historic manufacturing formulas. The interdisciplinary and novel methodology used for analysis of the earthen building materials combine geological, chemical, mineralogical, geotechnical, and mechanical approach. The results presented in this article enable a better understanding of material culture and advance the study of damage and decay processes found in the temple buildings. In addition, a suitable conservation and preservation strategy is presented.  相似文献   
44.
This article reports the efficacy of a research-based learning (RBL) exercise on hydropedology of arid zones, with guided and open research projects (OPR) carried out by teams of undergraduate students in Oman. A range of activities and assessments was used to support student learning during the three-month course. Assessment included monitoring of field trip and lab activities, attendance recording, scrutiny by a panel of written reports and open oral presentations. Students’ feedback through teaching evaluation is compared with other courses in the Department-College, illustrating high level of students’ satisfaction. OPR best fit the scaffold of RBL.  相似文献   
45.
The ‘pollen washes’ technique, based on the analysis of the pollen embedded in the porous surface of archaeological artefacts, is developed for investigating past plant usage and consumption and to characterize the functionality of artefacts related to plant processing, gathering and storage. The research presented results in relevant methodological improvements of this technique, which has never previously been applied on materials from European contexts. The improvements allow: (1) faster analysis of a broad series of artefacts or those with large use‐surface areas likely to retain more pollen; and (2) a more thorough, deeper and precise cleaning method, allowing the study of smoother artefacts. Finally, the recovery of Trifolium‐group pollen from a macro‐lithic tool from Xicotó rock shelter (Montsec ranges, Spain) demonstrates that the pollen washes technique can reveal new insights into both the use and consumption of wild and domestic plants by prehistoric societies, and the functionality of archaeological objects whose interpretation is still problematic.  相似文献   
46.
梯田是治山保水的重要措施,山西省柳林县的梯田建设在集体化时期经历了一个从无到有、从小到大的发展历程。贺昌农业社和韩家峪大队带动了黄土高原地区梯田建设的更新换代,普通百姓对梯田从排斥到接受、推广,其关键原因在于梯田能为农业生产带来实质性帮助,这也是梯田在集体化时期治理黄土高原丘陵沟壑区水土流失的最大价值所在。  相似文献   
47.
Abstract

Uplands have long been considered important ‘barometers’ for human-environment relationships. Five pollen sequences from the upper Aber Valley (Snowdonia), across an altitudinal gradient, reveal that human impacts have varied temporally on small spatial scales in the region. Woodland taxa persisted into the later Holocene at lower altitudes and sites located at higher altitude reveal a more open landscape history, possibly as a result of increased exposure limiting tree growth at high elevation. Continuous pastoral human land use is evident in the high upland (400 to >600 m AOD) landscape with evidence of clearing, burning and grazing indicators throughout the records covering the last ~6000 years, with increased activity apparent during the last 2000 years. There is no clear evidence to suggest that climate change (e.g. deteriorating climatic conditions from ~850 BC) resulted in land abandonment and it appears more likely that climatic shifts could have led to changes in human land management. The results demonstrate that pastoral land use varied at different altitudes across the Aber Valley upland, and have highlighted the value and potential of high/fine spatial sampling in providing insights into land use history and the mosaic of habitats that result.  相似文献   
48.
Abstract

Within the scope of an interdisciplinary research project to determine the genesis and age of small clusters of oak trees, three soil sections in and three outside oak clusters in an ancient woodland/heath on the Veluwe, central Netherlands, were sampled for palynological analysis. The sections within the clusters show an undisturbed development from the Medieval period onwards, the sections outside the clusters are missing ca. 15 cm because of sod cutting associated with plaggen soil formation. The rate of downward movement of pollen was established, using known dates from the near surroundings.  相似文献   
49.
The habitat and habit of Australia's first recorded Tertiary marsupial species, Wynyardia bassiana, found some 130 years ago at Wynyard on the northwestern coast of Tasmania, remain enigmatic (Aplin 1987, Aplin &; Rich 1990). Fossil pollen and spores preserved in a rafted clast of estuarine silts from the same sequence of earliest Miocene marine sandstones as the skeletal remains indicate the local vegetation was Nothofagus-gymnosperm evergreen rainforest, probably with a cryptogam-rich rather than woody subcanopy stratum. Comparisons with present-day Nothofagus rainforests suggest that, although the subcanopy would have been sufficiently open to allow the passage of a large ground-dwelling herbivorous marsupial, limited food resources are more consistent with Wynyardia being a generalist arboreal herbivore.  相似文献   
50.
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