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1.
Hadeda Ibis (Bostrychia hagedash) have increased in population size and expanded in range in South Africa possibly as a result of increased use of exotic trees for nesting and roosting in urban areas. We investigated the urban nesting and roosting sites of the Hadeda Ibis by measuring tree height and species used by Hadeda Ibis for nesting and roosting in Pietermaritzburg, KwaZulu-Natal, South Africa. We expected Hadeda Ibis nests and roosts to have habitats, like wetlands, to be within 10 km of the roost or nest tree. Hadeda Ibis nest and roost locations were mapped using ArcGIS and available resources (grasslands, wetlands, plantations, other natural water sources) 10 km around each roost and nest tree were determined. Results showed that Hadeda Ibis use exotic trees for nesting and roosting in urban areas more than indigenous trees. This may be because exotic trees are more available in urban environments, particularly those trees that have ornamental value. Hadeda Ibis did not nest and roost closer to expected resources. Although previously associated with wetlands, Hadeda Ibis in urban environments were not close to natural water sources. This can be explained by swimming pools providing accessible drinking water and well watered lawns providing suitable foraging habitat therefore allowing them to roost and nest in this urban habitat.  相似文献   

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The global spread of urban development and concomitant reduction in wilderness areas can both pressure and entice wild animals to adapt to the urban environment. As wildlife moves into metropolitan areas, however, they come into contact with residents who have become increasingly disconnected from natural environments and have little to no experience in dealing with wild animals. While many large carnivores actively avoid urban areas, North America’s coyote (Canis latrans) has proved remarkably adept at utilizing the highly altered habitat of the modern city. Yet while the coyote’s behavioural adaptations to urban areas have been relatively well researched, fewer studies have focused on human-coyote interactions in cities. Given that human attitudes, fears, knowledge and resulting behaviours often underpin human-wildlife conflicts, the following study investigates and compares the human aspects of coyote conflict in two cities with large populations of both people and coyotes: Chicago and Los Angeles. Data were collected via email surveys sent to residents of Cook and Los Angeles Counties. The survey instrument included questions on residents’ opinions, fears, knowledge, personal experiences with urban coyotes and behaviours affecting them. The general goal of the study was to investigate the potential for human-coyote coexistence in urban environments. The following research revealed great variation in attitudes towards coyotes, with animal lovers being as much a part of the problem as those with a paralyzing fear of wildlife. Consequently, finding acceptable solutions may pose a significant challenge to urban wildlife managers and reconciliation ecologists.  相似文献   

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Modern medicine faces fundamental challenges that various approaches to the philosophy of medicine have tried to address. One of these approaches is based on the ancient concept of phronesis. This paper investigates whether this concept can be used as a moral basis for the challenges facing modern medicine and, in particular, analyses phronesis as it is applied in the works of Pellegrino and Thomasma. It scrutinises some difficulties with a phronesis-based theory, specifically, how it presupposes a moral community of professionals. It is argued that Pellegrino and Thomasma's concept of phronesis corresponds to a Hippocratic concept of téchnê, and that this latter concept seems to address many of the challenging issues Pellegrino and Thomasma also address. Thus, if modern medicine is to find its philosophical model in ancient concepts, it appears that the Hippocratic téchnê is closer to the ancient concept of medicine than the Aristotelian phronesis, and that it might avoid many of the pitfalls of a phronesis-based approach.  相似文献   

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Urbanization has caused the local extinction of several butterfly species around the world, while others have managed to thrive in urban areas. Butterflies of the genus Eumaeus are among the most striking and colorful lycaenid butterflies in the Americas, but their neurotoxic hostplants, cycads, are a highly threatened plant group. The main threats for cycads are the loss and modification of their habitats and their removal for ornamental purposes, which in addition to their slow growth rate, make them highly vulnerable. Ornamental cycads are taken from natural habitats to urban areas, where they are playing an important role for Eumaeus reproduction. We here report two cases in which two Eumaeus species (E. childrenae, E. atala) are following and utilizing ornamental cycads to reproduce in urban areas, showing how significant urban areas can be, ecologically speaking. Aside from having enormous potential as flagship species for conservation in urban areas, these butterfly and plant species, and their interactions, shed encouraging light on the idea of putting reconciliation ecology ideas into action.  相似文献   

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Since the late nineties, stock market investments have become an attractive option for many who want to secure or improve their standard of living, although ?stocks“ are an obscure subject for most of them. They have to rely on investment consultants in banks. Until the stock market crash, there was no reason to complain about the consulting process — shares kept going up in value.But it is remarkable that following the crash, which caused many investors to lose a large amount of money, the relationship between private investors and investment consultants does not seem to have been damaged.In our paper we first show the legal requirements for investment consulting and how these requirements are implemented by banks, and we identify considerable discrepancies between the theoretical and the actual fulfillment of these legal requirements.We then show that it is impossible to meet these requirements in reality because they rely on unrealistic assumptions regarding a consulting process that both adequately covers investment options and addresses the needs of investors. We argue that both sides are more or less satisfied with the situation because they operate on an as if basis: consultant and client talk and behave as if they understood each other.As if the consultant had really informed the client and as if the client had really understood the consultant. This as if which both parties are aware of but which is not openly discussed is the condition of a successful consultancy process and for making the business happen.  相似文献   

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This study is a first attempt to estimate the degree of tritrophic association between the common dandelion Taraxacum officinale complex, the herbivorous weevil Glocianus punctiger and its parasitoid Entedon costalis, as an environmental marker in urban ecosystems. The study was conducted on 3926 dandelion flowering stems spread across 24 sample plots situated within the municipal borders of Kyiv (Ukraine). Eighteen plots were infested by the weevils, and 14 plots were infested by E. costalis. Of all the examined dandelion stems, 359 (9.1 %) were infested by weevils, and 21.4 % of these weevil-infested stems were parasitized by E. costalis. Thirty-two incidents of superparasitism were registered in nine sample plots. Seven environmental variables were chosen for characterization of the sample plots and for testing their possible effects on the tritrophic association. The results indicate that the infestation of dandelions by weevils is strongly limited by the grasslands’ mowing. Apart from that, the presence of anthropogenic barriers bounding the study areas negatively affected the parasitism of G. punctiger by E. costalis. This is regarded as an example of the crucial effect of habitat fragmentation on the specialist herbivore and the specialist parasitoid of this tritrophic system. Both the mowing and habitat fragmentation are linked with human land-use regimes on the sample plots.  相似文献   

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In cities, landscape palms and trees are planted for scenic views and normally maintained with frequent irrigation. With similar water input, their morphological difference may lead to different water-use that varies seasonally. Thus, evaluating their water-use patterns is necessary to achieve proper urban water management. Here, we examined water-use characteristics of Tabebuia argentea and Ptychosperma macarthurii, a tree and a palm species, in a roof garden in Bangkok, Thailand. Self-constructed Granier’s probes were used for sap flux measurement and monitored for five months in 2016. Results showed that palm transpired 3–4 times higher water than tree daily. With frequent watering, tree was more sensitive to increasing vapor pressure deficit (D) than palm on rain-free days. When rainfall occurred, however, both species became less sensitive to D and continued consuming more water at high D. Extending the analysis to include a hypothetical warming climate with +4.8 °C temperature, we found that tree saved more water than palm on rain-free days. However, daily transpiration of both species increased similarly by 14–18% on rainy days. These results imply that Tabebuia argentea may provide ecosystem benefits by conservatively using water under drought and decelerating runoff from the garden when storms come. In contrast, Ptychosperma macarthurii may provide ecosystem disservice with high water-use in dry season but may slow down runoff in wet season and therefore benefiting downstream ecosystems. These findings are useful for selective planting associated with future changes in precipitation patterns, leading to sustainable urban water management.  相似文献   

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Foraging decisions reflect a trade-off between the benefits of acquiring food and the costs of movement. Changes in the biotic and abiotic environment associated with urbanization can alter this trade-off and modify foraging decisions. We experimentally manipulated foraging opportunities for two Anolis lizard species – the brown anole (A. sagrei) in Florida and the crested anole (A. cristatellus) in Puerto Rico – to assess whether foraging behavior differs between habitats varying in their degree of urbanization. In both urban and natural forest habitats, we measured the latency of perched anoles to feed from an experimental feeding tray. We manipulated perch availability and predator presence, while also taking into account population (e.g., conspecific density) and individual-level factors (e.g., body temperature) to evaluate whether and how these contribute to between-habitat differences in foraging behavior. In both species, urban anoles had longer latencies to feed and lower overall response rates compared to lizards from forests. Urban anoles were also larger (i.e., snout-vent length and mass) in both species and urban A. sagrei were in better body condition than the natural forest population. We postulate that the observed patterns in foraging behavior are driven by differences in perceived predation risk, foraging motivation, or neophobia. Although we are unable to identify the mechanism(s) driving these differences, the substantial differences in urban versus forest anole foraging behavior emphasizes the importance of understanding how urbanization influences animal populations and their persistence in anthropogenically-modified environments.  相似文献   

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Cavities represent a limiting resource for breeding birds, thus triggering potential competition, mostly in urban ecosystems. The ring-necked parakeet Psittacula krameri is one of the main alien invasive bird species of the world. Introduced populations are reported for over 35 countries, Italy included. This parakeet mainly depends on trunk cavities for reproduction but, occasionally, it may nest within building holes. A growing population of this species is present in the urban area of Pavia (northern Italy). Differently, from what has been observed in other colonies of the global introduced range, most of this urban population nests within the putlog holes of the Visconti castle and surrounding towers, together with four native species. In this work, we counted the breeding pairs of ring-necked parakeets nesting within putlog holes of castle and tower walls and estimated the breeding population size. Observations were carried out once a week, 30 min before sunset, for an hour, from the start of April to the end of August 2016 and 2017. We assessed whether a vertical segregation occurred between parakeets and native species (i.e. the rock pigeon, the jackdaw, the Italian sparrow and the common swift) through a dissimilarity index. Inter-specific interactions have never been observed, despite two pigeon ticks being detected on rescued parakeets. A strong vertical segregation was observed between ring-necked parakeets and pigeons, and between ring-necked parakeets and common swifts. Ring-necked parakeets and jackdaws were mostly observed in the highest putlog holes. No breeding parakeet pair was observed within plain trunk cavities in the surroundings of the castle walls, which were instead occupied by jackdaws and tawny owls. Most parakeet nests were located on the eastern wall, where they receive the first light at dawn.  相似文献   

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This is a book review of Ebenezer Obadare’s “Humor, Silence and Civil Society in Nigeria.” It examines conceptual issues around the role of civil society in Nigeria, the nexus (or lack thereof) between ngo’s and civil society, and the roles that humor and silence play as roles of agency in how a population responds to oppression and the suppression of dissent.  相似文献   

17.
Journals may set themselves one or several of a range of missions, but often a national Sociology Association’s journal is concerned to be a vehicle assisting in the shaping of that country’s ‘national sociology’, while maintaining some openness to international sociology. This personalised case study of New Zealand’s sociology journal discusses the extent to which this mission has been achieved over the last decade and more generally over the journal’s history, and the nitty-gritty of challenges and operational issues involved in carrying this out.  相似文献   

18.
Since the “Public Library of Science” launched its first open-access journals and the “Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities” has been released in 2003 and found enormous attention, the claim for open access—to make publicly funded journal articles available for the public—started to reach German scientists too. But still no experience has been made with electronic publishing in general and more specifically with open-access publishing. One consequence is that the potential capacity of open access—the (inter) national and (trans) disciplinary visibility and accessibility of scientific output—is not sufficiently used by German researchers. Ways to successfully establish an open-access journal are presented in this article by referring to “Forum Qualitative Sozialforschung/Forum:Qualitative Social Research” (FQS) as an example: after introducing the current state of FQS traditional and innovative ways of publishing are being discussed which had been employed while developing FQS and which helped FQS to become the most important electronic journal in the field of qualitative research.  相似文献   

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Little is known about the environmental factors that limit the demography and abundance of wild vertebrates in highly modified urban environments. The House Sparrow Passer domesticus is a globally widespread species whose urban populations have recently undergone substantial declines particularly in Europe. The environmental drivers of these declines remain unknown. In a previous study we showed that invertebrate availability during the breeding season limited reproductive success but not population size in a suburban sparrow population. In this study we test experimentally whether year-round food availability limits demography and population size. Supplementary feeding involved the provision of invertebrate prey (during the breeding season) plus unlimited high-energy seed (year-round) at 33 sparrow colonies spread across suburban London over two successive calendar years. Thirty-three unfed colonies served as controls. Supplementary feeding increased fledgling abundance, but had no impact on overwinter survival or population size. We conclude that this depleted suburban sparrow population is not limited by food availability, and conservation efforts based primarily on food provision are unlikely to succeed. We also tested whether cross-colony variation in sparrow abundance was correlated with a set of potential environmental stressors including measures of predator abundance and pollution. Sparrows were more abundant, or showed more positive temporal changes in abundance, at localities containing large areas of seed-rich habitat and low levels of nitrogen dioxide air pollution. Further research is merited into the potential impacts of air pollution on the fitness of urban birds.  相似文献   

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During the year 2005 many organizations took part in Poverty Zero, a campaign that aims to reach the United Nation’s Millennium Development Goals for 2015. Based on participant observation and open ended interviews, this paper describes the origins, development, and evaluation of Poverty Zero in Andalusia (Spain). It examines, by means of ethnography, how DNGOs (Development Nongovernmental Organizations) create social movement networks, and explores the limits and possibilities of their advocacy activities. The paper concludes that DNGOs tend to generate centralized social movements with reduced questioning of the global system. Nevertheless, as shown in the case of the Andalusian Alliance against Poverty, the more decentralized a movement, the deeper its transformational potential.
Beltrán RocaEmail:
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