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81.
This paper shows that tree-ring trends might be used for the assessment of the intensity of trampling along touristic tracks in the forests. The study aims at determining the effects of trampling, on the dynamics of annual increments in trees subject to pressure from hiking tourism. The studies were conducted at a spruce stand in the Tatra Mts., on sections of different trails. Within each trail, four transects were determined. Transects include the zones with damage from trampling and the un-affected areas, treated as a reference zones. Selected trees growing in both zones were sampled by coring and the core samples were used to develop sequences of annual increment widths. Next, the dynamics of increments in trees growing in the tourist zone and the reference zone were compared. The decrease in the annual increments was significantly more rapid in trees growing directly along the trail that those in trees deep in the forest stand in one locality. This finding may testify the adverse effects of hiking along tourist routes on the radial increments in trees in the neighbourhood of the trails. The results of the study indicate that the impact of trampling in the form of soil compaction and mechanical damage to root systems of trees may, to some extent, be compensated by better light access and lessened competition experienced by trees growing along the edges of hiking trails. Tree-ring analyses might be an efficient alternative for assessment of tourism intensity conducted by the other methods.  相似文献   
82.
The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria. The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.  相似文献   
83.
The goal of this article is to identify the impact of innovations on growth and stagnation regions in Poland. The research procedure consists of two stages. At stage one, Polish administrative units (voivodeships) were arranged on a scale of economically robust and weak regions following data clustering, indicators organized in line with the following aspects of social and economic growth: (1) population and settlement, (2) the economy structure and the labour market, (3) the technical infrastructure and spatial accessibility and (4) the financial situation and level of affluence. Stage two includes identification of the relation between the regional diversification and the distribution of growth and stagnation regions in Poland which is based on canonical correlation.  相似文献   
84.
Stable isotope analyses of faunal remains provide valuable information about human–environment interactions in the past, including insights into past animal husbandry and land management strategies. Here, we report stable carbon (δ13C) and nitrogen (δ15N) isotope values of collagen and carbonate from archaeological fauna from Ka?dus, a medieval settlement in North-Central Poland, to better understand human–environment interactions during a period of increasing urbanism and marketization. Wild and domestic animals can be separated on the basis of their isotopic values. The mean δ15N value for 12 domesticated animals is 7.6 ± 1.2‰ and for 5 wild animals is 4.3 ± 0.5‰ (p = 0.002). The mean collagen δ13C value for domesticated animals is −20.6 ± 1.1‰ and for wild animals is −22.0 ± 0.5‰ (p = 0.004). The mean carbonate δ13C value for domesticated animals is −13.14 ± 1.3‰ and for wild animals is −14.14 ± 0.9‰ (p = 0.034). The “canopy effect” and anthropogenic effects that alter stable isotope ratios of plants (manuring, swidden agriculture and ploughing) are discussed in relation to these differences. Fish are isotopically variable, which suggests broad-spectrum fishing strategies and/or trade, and increases our awareness of the difficulties in interpreting human paleodiet when freshwater fish were on the menu.  相似文献   
85.
ABSTRACT

Sustainable nature-based tourism was brought to the public's attention as a solution to the problem of economic diversification in Central and Eastern European (CEE) communities included in European Ecological Network – N2000. However, Natura 2000 tourism development has not yet proven to be an effective way to boost local economies and the notion of sustainable tourism based on Natura 2000 resources has been challenged by residents of the CEE communities. The study goal was to explore issues concerning Natura 2000 tourism from the perspective of local residents within three municipalities of Ma?opolska in Poland to determine if Natura 2000 is perceived by local residents as a valuable tourism asset. We employed a mix-mode methodology: an in-depth interview and public participation GIS mapping task. The study results highlight several areas of concern regarding resident perspectives of Natura 2000-based tourism: first, the misconception that residents need and want nature-based tourism when other economic activities provide sufficient income; second, the misconception that Natura 2000 is considered a valuable asset when other tourism attractions in a municipality attract more visitors; third, the residents misconception of nature-based tourism itself; and last but not least the importance of engaging with residents when assessing the potential for Natura 2000 tourism. These findings can assist policy-makers and tourism managers with prioritizing avenues for further action.  相似文献   
86.
Christian Nubia was a region with intensive transcultural connections that are visible through the understudied overseas glass bead imports found there. This paper presents the results of an analysis of 20 glass beads from Banganarti, a Christian pilgrim site active during the Makuria kingdom (mid-sixth to 14th centuries CE). Compositional analyses using laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) have identified glass belonging to a number of broad compositional groups. Two beads were made of mineral soda-lime glass, dated before the mid-ninth century CE. Numerous beads were made from plant ash-soda-lime glass associated with “Mesopotamian” production dated between the eighth and 10th centuries CE. Lead-soda-silica glass has parallels in the ninth–10th centuries glass found in Africa and Europe. One plant ash-soda-lime bead was of eastern Mediterranean origin dated after the 10th century CE. Results of this study provide new evidence for provenance and chronology of glass beads available in the mediaeval Northeast Africa as well as contribute new data to the research on the pilgrim and/or trade routes of that time.  相似文献   
87.
The question on how regional clusters renew themselves and start a new cycle of prosperity is of vital interest for affected companies, politicians and regions. Recently, the idea of renewing clusters has been conceptualized within the cluster life cycle (CLC) literature. CLC approaches generally assume that cluster renewal is widely driven cluster-internally through agent capability building processes and the systemic utilization of novelty. Critique from other authors highlights the neglected role of the external environment in the CLC literature. This article sheds light on renewal processes in two German agricultural engineering clusters. It is shown that in the case of a farm trailer cluster renewal can be widely explained cluster-internally, while in the case of a stable technology cluster that diversified into the field of biogas technology, internal factors played a less significant role and much of the development was driven externally by political decisions on the national level. Possible explanations for diverging roles of cluster-internal and external factors lie in the differences in the stage of the novel technologies’ development and the complexity of the novel technology.  相似文献   
88.
89.
Fish remains have been discovered at seven Mesolithic sites located mainly in central and northern Poland, an area that is known as the Lakeland of the Polish Lowland. Based mainly on the results of the identification of fish remains uncovered during the excavations at the Site 7 in Krzy? Wielkopolski (Western Poland), the conclusions were made on the locality and technique of fishery. The fish taxa represented show that the fishing showed that the fishing economy during the Mesolithic period was focused on nearby freshwater rivers and lakes. At that time, people fished primarily for Cyprinids, pike and perch. According to the archaeological finds, the basic fishing tools used by the Mesolithic communities were spears, harpoons and rods with hooks. The small fishes recovered were most probably caught by fishing traps or nets, but such artifact finds are very rare in the Polish Lowland. This paper summarises the current data on Mesolithic fishery in the Polish Lowland based mainly on the data from the Site 7 at Krzy? Wielkopolski, but also includes archaeological data collected from previous studies in the region.  相似文献   
90.
A range of reinforced concrete frame buildings with different levels of inelasticity as well as periods of vibration is analyzed to study the floor response. The derived floor acceleration response spectra are normalized by peak ground acceleration, peak floor acceleration, and ground response spectrum. The normalization with respect to ground response spectrum leads to the lowest coefficients of variation. Based on this observation as well as previous studies, an amplification function is proposed that can be used to develop design floor spectra from the ground motion spectrum, considering the building’s dynamic characteristics and level of inelasticity.  相似文献   
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