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61.
Many species are restricted to a marginal or suboptimal fraction of their historical range due to anthropogenic impacts, making it hard to interpret their ecological preferences from modern-day data alone. However, inferring past ecological states is limited by the availability of robust data and biases in historical archives, posing a challenge for policy makers . To highlight how historical records can be used to understand the ecological requirements of threatened species and inform conservation, we investigated sperm whale (Physeter macrocephalus) distribution in the Western Indian Ocean. We assessed differences in information content and habitat suitability predictions based on whale occurrence data from Yankee whaling logs (1792–1912) and from modern cetacean surveys (1995–2020). We built maximum entropy habitat suitability models containing static (bathymetry-derived) variables to compare models comprising historical-only and modern-only data. Using both historical and modern habitat suitability predictions  we assessed marine protected area (MPA) placement by contrasting suitability in- and outside MPAs. The historical model predicted high habitat suitability in shelf and coastal regions near continents and islands, whereas the modern model predicted a less coastal distribution with high habitat suitability more restricted to areas of steep topography. The proportion of high habitat suitability inside versus outside MPAs was higher when applying the historical predictions than the modern predictions, suggesting that different marine spatial planning optimums can be reached from either data sources. Moreover, differences in relative habitat suitability predictions between eras were consistent with the historical depletion of sperm whales from coastal regions, which were easily accessed and targeted by whalers, resulting in a modern distribution limited more to steep continental margins and remote oceanic ridges. The use of historical data can provide important new insights and, through cautious interpretation, inform conservation planning and policy, for example, by identifying refugee species and regions of anticipated population recovery.  相似文献   
62.
We examined evidence for kin-related signal discrimination in the Australian scincid lizard Egernia striolata, using 41 juvenile lizards from 14 litters from a population in the Mount Lofty Ranges, South Australia. We characterised each juvenile at four polymorphic microsatellite DNA loci, determined genetic relatedness among pairs of juveniles, and assigned for each litter one other litter that was genetically closest and one other litter that was genetically most distant. Lizards responded significantly more strongly, with tongue flicks and time in contact, to skin secretion stimuli from more distant than genetically close, unfamiliar conspecific juveniles. When presented with an intruder, juvenile lizards basked for shorter periods when the intruder was more distantly related, and aggressive lizards directed more aggressive acts towards more distantly related than closely related conspecific intruders. We deduce from these results that there is kin recognition in juvenile E. striolata, and that they are able to discriminate related from unrelated individuals among unfamiliar conspecifics.  相似文献   
63.
Inorganic arsenic and trace elements in Ghanaian grain staples   总被引:1,自引:0,他引:1  
A total of 549 samples of rice, maize, wheat, sorghum and millet were obtained from markets in Ghana, the EU, US and Asia. Analysis of the samples, originating from 21 countries in 5 continents, helped to establish global mean trace element concentrations in grains; thus placing the Ghanaian data within a global context. Ghanaian rice was generally low in potentially toxic elements, but high in essential nutrient elements. Arsenic concentrations in rice from US (0.22 mg/kg) and Thailand (0.15 mg/kg) were higher than in Ghanaian rice (0.11 mg/kg). Percentage inorganic arsenic content of the latter (83%) was, however, higher than for US (42%) and Thai rice (67%). Total arsenic concentration in Ghanaian maize, sorghum and millet samples (0.01 mg/kg) was an order of magnitude lower than in Ghanaian rice, indicating that a shift from rice-centric to multigrain diets could help reduce health risks posed by dietary exposure to inorganic As.  相似文献   
64.
A field survey was conducted in arsenic impacted and non-impacted paddies of Bangladesh to assess how arsenic levels in rice (Oryza sativa L.) grain are related to soil and shoot concentrations. Ten field sites from an arsenic contaminated tubewell irrigation region (Faridpur) were compared to 10 field sites from a non-affected region (Gazipur). Analysis of the overall data set found that both grain and shoot total arsenic concentrations were highly correlated (P<0.001) with soil arsenic. Median arsenic concentrations varied by 14, 10 and 3 fold for soil, shoot and grain respectively comparing the two regions. The reason for the sharp decline in the magnitude of difference between Gazipur and Faridpur for grain arsenic was due to an exponential decline in the grain/shoot arsenic concentration ratio with increasing shoot arsenic concentration. When the Bangladesh data were compared to EU and US soil-shoot-grain transfers, the same generic pattern could be found with the exception that arsenic was more efficiently transferred to grain from soil/shoot in the Bangladesh grown plants. This may reflect climatic or cultivar differences.  相似文献   
65.
Latino social network dynamics and the Hurricane Katrina disaster   总被引:2,自引:0,他引:2  
The aim of this qualitative research was to examine the dynamics of existing and emerging social networks among Latino survivors of Hurricane Katrina. Data were generated through individual, in-depth interviews conducted with 65 Latinos within six months of the storm striking the Gulf Coast of the United States in August 2005. The findings illustrated both the role of social networks in gathering information, making decisions and accessing resources, and how these existing social networks were disrupted and strained by overwhelming needs. Broader structural issues, including poverty and a lack of transportation, combined with marginalised status as immigrants, further constrained access to essential information and resources. In response, new, if temporary, social networks emerged, based primarily on shared nationality, language, and a sense of collective commitment. Practice implications include the need to consider the social network dynamics of marginalised groups in developing innovative strategies to overcome structural barriers to accessing resources essential for disaster preparedness and survival.  相似文献   
66.
PROBLEM: This study aimed to provide an assessment of the contribution of design to the occurrence of fatal work-related injuries in Australia. METHODS: The Australian National Coroners' Information System was the data source for fatal injuries. Deaths resulting from workplace injuries on or between 1 July 2000 and 30 June 2002 were included. RESULTS: Seventy seven (37%) of the 210 identified workplace fatalities definitely or probably had design-related issues involved. In another 29 (14%), the circumstances were suggestive that design issues were involved. The most common scenarios involved problems with rollover protective structures and/or associated seat belts; inadequate guarding; lack of residual current devices; inadequate fall protection; failed hydraulic lifting systems in vehicles and mobile equipment; and inadequate protection mechanisms on mobile plant and vehicles. SUMMARY: Design is a significant contributor to work-related fatal injury in Australia. There is considerable scope for preventing serious work-related injury through improving design of plant, equipment, and vehicles used for work-related purposes.  相似文献   
67.
Svejcar et al. (Environ Manage, 2014) offered several perspectives regarding Beschta et al. (Environ Manage 51:474–491, 2013)—a publication that addressed the interacting ecological effects of climate change and domestic, wild, and feral ungulates on public lands in the western United States (US)—by largely focusing on three livestock grazing issues: (1) legacy versus current day impacts; (2) grazing as a fire reduction tool; and (3) the complexity of grazing. Regarding these issues, we indicate that (1) legacy effects to western ecosystems were indeed significant and contemporary livestock use on public lands generally maintains or exacerbates many of those effects; (2) livestock grazing has been a major factor affecting fire frequency, fire severity, and ecosystem trajectories in the western US for over a century; and (3) the removal or reduction of grazing impacts in these altered ecosystems is the most effective means of initiating ecological recovery. Svejcar et al. (Environ Manage, 2014) offer no evidence that livestock use is consistent with the timely recovery of grazing-degraded uplands, riparian areas, or stream systems. We thus conclude that public-land ecosystems can best persist or cope with a changing climate by significantly reducing ungulate grazing and related impacts.  相似文献   
68.
Environmental Management - Rural households in South Asia’s coastal deltas face numerous livelihood challenges, including risks posed by climatic variability and extreme weather events. This...  相似文献   
69.
The recent growth of interest in sustainable development has led to the incorporation of the concept into policy making at a variety of scales. In all cases particular emphasis is placed upon the local scale as the focus for the implementation of policy and initiatives and especially upon local authorities as the major contributor to this process. There has been little assessment, however, of the extent to which local authorities either can, or are, undertaking such initiatives. This paper examines: the potential role that local authorities can play in integrating economic development and the environment; the forms of response and initiatives that are currently in place, drawing upon survey evidence from urban local authorities in England and Wales; and some of the limits to local authority action.  相似文献   
70.
Malpuech syndrome (MS) is a rare autosomal recessive syndrome featuring pre- and post-natal growth deficiency, mental retardation, facial dysmorphism, cleft lip and palate (typically midline or bilateral), caudal appendage, renal malformations and male genital abnormalities. A prenatal diagnosis of MS was made in this fetus based on the family history and a combination of conventional and 3D prenatal ultrasound findings. The family were consanguineous with an affected first child. Prenatal ultrasound in the second pregnancy demonstrated bilateral cleft lip and palate in association with intrauterine growth retardation on serial prenatal ultrasound scans. Dysmorphic facial features and a small penis consistent with the diagnosis were confirmed on 3D scanning. Post-natal examination of the neonate confirmed the diagnosis of MS. To the best of our knowledge, this is the first prenatal diagnosis of this syndrome. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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