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In this paper, we show how the Aboriginal people in the south-west of Australia (the Nyungar) developed systems of knowledge, of caring for country and of family relations that enabled them to survive for tens of thousands of years and continue to have importance today. The impacts of British colonisation on cultural continuity and knowledge in the south-west have been significant and include loss of land, break-up of families and massacre. These practices led to a loss of knowledge of language and culture in some cases. However, Nyungar culture is alive and dynamic, constantly being reclaimed, re-energised and rebuilt through the interaction of contemporary and traditional research praxis. Focusing on Derbal Nara (Cockburn Sound) on the coast in the southern metropolitan area of Perth, we provide case examples of the action-research-learning methodologies used by Whadjuk Nyungar Traditional Owners. We also provide examples of stories about Derbal Nara that are still alive and being recounted up to the present day, including those that account for the recent ice age and the end of the ice age 8000 years BC when sea levels rose, drowning land in the area of Derbal Nara. Finally, we argue that Whadjuk Nyungar experiences and world views based on relationality and reflexivity are central to sustainable coastal management and that in some respects there has already been a convergence of Indigenous and Western coastal management. We present a set of principles that support the development of this “third space” for coastal sustainability.  相似文献   
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Indirect measures were considered to study the lead transfer along the soil-melliferous flora-bee family-apiary products food chain. The concentrations of total and bioavailable lead in the soil were first investigated. Next, the lead level in different organs of melliferous flora and subsequently in the bee family and apiary products was measured. The results indicate a decrease in contamination as follows: honeybees > drones > propolis > wax > bee larvae > honey > royal jelly. The statistical analysis highlights the "lead pollution bioindicator" role of honeybees, honey and propolis. The risk factor parameter allows the prediction of the most impacted month and the least impacted of the melliferous season.  相似文献   
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Environmental Science and Pollution Research - Hunting, trapping, and fishing are part of an Indigenous lifestyle in subarctic Canada. However, this lifestyle may be a route of exposure to...  相似文献   
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We present a demographic analysis and suggestions for the conservation of Beaucarnea gracilis, a species endemic to the Tehuacán Valley, Puebla, México. The species is dioecious, it flowers every year, and the breeding system and floral display are typical of a generalist mode of pollination. The density of B. gracilis in the study plot was 16.7 individuals/ha. Distribution of trunk diameter size classes fits a normal distribution (n = 404), but the smaller sizes were not found (<0.7 m). The inflorescences were visited by 46 insect species. Over 2600 seeds are produced per inflorescence; 27–30% are damaged by parasites, and the rest germinate readily (90–100%). Survival of seeds and seedlings is very low. We found 313 seedlings in a 12-ha area, all (94.24%) of which were at the base of nurse plants; particularly Mimosa luisiana and Castela tortuosa. The ecological status of the population of Beaucarnea gracilis is relatively good for adult individuals. In addition to low recruitment, (whether natural or human influenced), past extraction of seedlings for commerce, grazing by goats, and land clearing for corn cultivation, highway construction, and urbanization, are a real threat to the survival and establishment of seeds and seedlings. Conservation of this slow-growing, long-lived species should be promoted because (1) ecologically, it is a feeding center for many insect species, an important host for many Bromeliaceae, and part of the highly rich and endemic flora of Tehuacán and (2) economically, it helps low income people in the area (seedlings raised for commerce). Protection of nurse plants, regulation of grazing by goats, a halt to illegal extraction, and conservation of areas of the Tehuacán valley will help the survival of this species in nature.  相似文献   
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The subcellular distribution of 237Pu in the livers of the plaice Pleuronectes platessa has been studied by differential and isopycnic gradient centrifugation. It has been shown that the 237Pu is particularly accumulated in pellets sedimenting out at 3000 and 6000 g which, by deduction from marker enzyme tests, contain a mixture of mitochondria and lysosomes. Separation of lysosomes from mitochondria was achieved by using a non-lytic detergent injected into the fish 3 d prior to removal of the livers; it was found that 237Pu was associated with the lysosomal fraction. In this respect, the metabolism of plutonium of the plaice resembles that of the rat.  相似文献   
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Interactions between nestling birds and their parents are models for examining parent–offspring communication and sibling competition. Most studies have focused on species where young are restricted to a nest. However, offspring of many species are mobile and fed by parents for an extended period post-hatch. These chicks mobility may provide an opportunity to examine the role of signalling and physical competition on parental feeding decisions. We examined parental provisioning rules in relation to offspring behaviour and hatching order (i.e., competitive ability) in a species with mobile young, the common tern. We determined that about 95% of feedings were directed to the first chick to reach the parent when it landed with food. We developed a probabilistic model to predict the likelihood of a chick reaching the parent first, and thus receiving food. Our model showed that begging intensity, feeding history, and the interaction between begging intensity and relative proximity to the parent best predicted which chick would arrive first. Increased begging was associated with arriving first significantly more when a chick was relatively further from the parent than when it was closer than its siblings. Independently of these factors, larger, earlier-hatched chicks were more likely to be fed than smaller, later-hatched chicks. Additional analyses showed that parents landed closer to more intensively begging chicks, however, increased begging did not explain the advantage of earlier-hatched chicks because begging intensity did not vary with hatching order. Instead, earlier-hatched chicks were more likely to outrun later-hatched siblings and reach the parent first.  相似文献   
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