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1.
Over the last decades, Poland has witnessed a relatively dynamic increase in the number of immigrants. At the same time, current Polish central authorities, politicians of the ruling party and the majority of the population perceive migrants mostly as a threat and a challenge. Municipal authorities lack complex support from central authorities. However, the situation is slowly changing. Some Polish cities are adopting migration policies or including migration issues in the local development strategies. Considering this, the article aims to examine migrants’ integration policies in selected Polish cites considered leaders in this field: Lublin, Gdańsk, Kraków and Wroc?aw. The main research question is: how do Polish cities deal with the backlash from the national government and absence of clear legal regulations on their role and competences in the area of migrant integration? The research method is that of a legal-institutional analysis and case study. The former is used to interpret the legal acts and other documents. Its application is justified by the fact that this paper examines strategic documents adopted at the level of urban governments regarding the integration of migrants. Case study methods made it possible to examine the migrants’ integration policy in four Polish cities.  相似文献   
2.
Organic fertilizers have the capacity to alter the nitrogen isotopic composition of plants. Camelid dung and seabird guano are two potentially important fertilizers in the agricultural systems of western South America, particularly Peru and Chile. This paper presents isotopic data (δ13C and δ15N) from field grown plants (maize, Zea mays) fertilized with the following four treatments: CO (control, no fertilizer applied), AS (ammonium sulfate, a chemical fertilizer), DU (camelid dung), and SG (seabird guano). Plants were grown in experimental plots in the Virú Valley, northern Peru. Plants fertilized with the chemical fertilizer presented very similar isotopic compositions compared to the control. Conversely, the camelid dung fertilized plants were characterized by higher δ15N values compared to the control plants (by 1.8 to 4.2‰ depending on the plant part). The seabird guano fertilized plants were greatly enriched in 15N in comparison to the control plants (by 11.3 to 20.0‰). The results of this study have important implications for the reconstruction of human diet using isotopic data derived from bone collagen and related tissues, particularly in the prehispanic Andes, but also in Europe and North America during the 19th century, when Peruvian seabird guano was used extensively. Specifically, the interpretation of the relative contributions of plant and animal protein to the diet on the basis of bulk isotopic compositions of bone collagen (or similar tissues) may be confounded by camelid dung fertilization if the carbon isotopic compositions of the two sources are similar. Likewise, the interpretation of the relative contributions of maize and marine protein may be confounded by seabird guano fertilization.  相似文献   
3.
Journal of Archaeological Method and Theory - Using stable isotope mixing models (SIMMs) to quantify past diets is becoming increasingly common in archaeology. This study highlights important...  相似文献   
4.
Journal of Archaeological Method and Theory - Palaeodietary reconstruction using stable isotope analysis is becoming increasingly common, as is the practice of using mixing models to quantify...  相似文献   
5.
Stable carbon and nitrogen isotopic compositions were determined for wool textiles from the Lambayeque (c. ad 1100–1320) occupation at Pacatnamú in the Jequetepeque Valley, northern Peru. The isotopic data demonstrate that the wool was not obtained via long‐distance exchange with the highlands and was most probably derived from locally raised camelids. In light of other lines of evidence (diversity of dyes used to produce the same colours in textiles and the low quality of the weaving), textiles at Pacatnamú appear not to have been as effective a marker of political power and prestige for local elites as they were elsewhere in the Andean region.  相似文献   
6.
Journal of Archaeological Method and Theory - Archaeological and palaeontological excavations frequently produce large quantities of highly fragmentary bone. These bones can help to answer...  相似文献   
7.
The maritime fur trade (1785–1840s) led to the local extinction of sea otters (Enhydra lutris) in many parts of the northeast Pacific. On the basis of studies of extant sea otter populations, it has been established that they have a disproportionate effect on nearshore ecosystems by limiting sea urchin abundance and facilitating the establishment of nearshore kelp forests; in the absence of sea otters, a local reduction in kelp-derived carbon is therefore expected. We measured the isotopic composition (δ13C and δ15N) of rockfish (Sebastes spp.) bone collagen from late Holocene archaeological sites in southern Haida Gwaii, BC, Canada, using δ13C as a proxy for kelp-derived carbon in the diet and δ15N as a proxy for trophic position. We observed significant spatial variability in rockfish kelp-derived carbon (δ13C), but not trophic level (δ15N). Kelp-derived carbon varied largely as a function of site characteristics (wave exposure), suggesting that local oceanographic conditions are important factors with respect to consumer tissue isotopic compositions. Kelp-derived carbon decreased in post-European contact rockfish relative to pre-European contact rockfish, likely as a result of the reduction of kelp forests associated with the local extirpation of sea otters. Although we detected a reduction in kelp-derived carbon in rockfish diets, we found no shift in trophic level at sites occupied following the maritime fur trade. This implies a shift in local ecosystems, and particularly in carbon sources, following the maritime fur trade, likely due to a trophic cascade resulting from the local extirpation of sea otters. Stability in rockfish trophic levels, however, implies that rockfish continued to feed at similar trophic levels, consuming prey with similar nitrogen isotopic compositions.  相似文献   
8.
This study presents isotopic data (δ13C and δ15N from bone collagen) for 104 samples representing 29 vertebrate taxa from late pre-contact through to contact era (ca. 2000 – 100 BP) Haida Gwaii (British Columbia, Canada) from a wide variety of mostly marine organisms. The results demonstrate the considerable isotopic variability that characterizes potential prey items in coastal contexts and underscores the need for baseline faunal data to interpret human subsistence practices. Based on these data, a detailed marine food web was constructed, which provides insight into local ecological conditions. We present a simple method for quantifying the trophic level of ancient fauna using δ15N of bone collagen. Finally, we discuss the implications of this study for the reconstruction of human diet.  相似文献   
9.
10.
We examined the isotopic composition (δ13C and δ15N) of sea otter (Enhydra lutris) bone collagen from ten late Holocene (ca. 5200 years BP–AD 1900) archaeological sites in northern British Columbia (BC), Canada. Because sea otters are now extinct from much of this region and have not fully recolonized their former range (e.g. Haida Gwaii and most of northern BC) these data represent an important first step towards better understanding sea otter foraging ecology in BC. The isotopic data suggest a diet composed primarily of benthic invertebrates, with a very low reliance on epibenthic fish. There is very low isotopic and thus inter-individual dietary variability in Holocene BC sea otters during the late Holocene. Furthermore, zooarchaeological abundance data suggest that otters represented a widespread and significant focus of aboriginal hunting practices on the northern BC coast during the mid- to late-Holocene. The consistent reliance on a small number of low-trophic level prey and limited dietary variability in Holocene BC sea otters may reflect top-down impacts on otter populations by aboriginal peoples. As part of our assessment of sea otter diet, we review trophic discrimination factors (Δ13C and Δ15N) for bone collagen from published literature and find marked variability, with mean values of +3.7 ± 1.6 for Δ13C (n = 21) and +3.6 ± 1.3 for Δ15N (n = 15).  相似文献   
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