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81.
Urbanization and other land cover changes have been particularly detrimental to wetlands throughout the planet. One wetland specialist that may be sensitive to land cover changes surrounding wetlands is the round-tailed muskrat (Neofiber alleni; hereafter RTM). The RTM is a wetland obligate rodent that appears to have declined over the last half century and is a species of concern in Florida, where it is a near endemic. To determine if urbanization or other land cover influenced the distribution of RTMs we took a multi-scaled approach to examine the occurrence of RTMs and their associated vegetation in North-Central Florida. We detected RTMs on 19 of 72 sample plots and used a Classification And Regression Tree (CART) to determine that dogfennel (Eupatorium capillifolium) was negatively associated with RTMs and maidencane (Panicum hemitomon) was positively associated with their occurrence on sampling plots. Examining the influence of landscape composition for 2 km surrounding our plots we found that RTM occurrence was negatively related to urban land cover. Further, we found that dogfennel increased and maidencane decreased as urbanization increased in the surrounding landscape. Our research suggests that conservation of RTMs and their associated vegetation should focus on limiting urban sprawl at least within 2 km of wetlands. 相似文献
82.
Maider?Iglesias-CarrascoEmail author José?Martín Carlos?Cabido 《Urban Ecosystems》2017,20(6):1331-1338
Does urbanization affect key life-history traits in native organisms? Some studies show that urban areas reduce diversity in certain taxa, but there is little insight into how these environments affect physiological and ecological traits. Urban areas have distinct physical structure and ecological processes compared to original habitats. The environmental changes associated with urban areas can influence the costs and benefits of different traits and behaviors of local organisms. Some of these effects have been explored in groups such as birds, but we might expect stronger effects in animals with reduced mobility, such as amphibians. Importantly, the effects of urban habitats on amphibians have not been explored, in spite that these are the most threatened vertebrate group in the world. Here, we compared three main traits related to the fitness of amphibians in urban and natural habitats: body size, body condition and immune response. To test the generality of our results, we assessed adult males of four amphibian species. We found that the body size was larger in urban environment populations in three of four studied species, while the body condition was better in the urban populations of two aquatic newt species. Finally, we found no effect of urbanization on the immune response of individuals of any species. In conclusion, we show that different species of amphibians may be affected differently by anthropogenic habitat alteration depending on their specific ecology. 相似文献
83.
A desirable function for terrestrial urban ecosystems is the mitigation of nitrogen (N) pollution associated with cities and suburbs. To assist in maximizing this function, identifying locations of sources and sinks of N in the urban environment is crucial to inform management strategies. Lawns are an extensive land cover in urbanized landscapes, and in general, they have demonstrated the capacity to function as a sink for N inputs. How N is cycled by lawns, however, is likely not uniform across the physical heterogeneity or management activities that exist in lawns. We investigated the influence of heterogeneity in light availability on N cycling in lawns that were irrigated but not fertilized. Light availability is affected by tree canopy and built structures and is, therefore, heterogeneous both within individual lawns and among lawns. Light is expected to control N retention and loss through effects on primary productivity. We experimentally examined N regulation over one calendar year by measuring net primary production (NPP), N retention using an isotopic tracer, and N leaching in existing unfertilized lawns under heterogeneous light conditions. We used a budgetary approach to estimate gaseous N loss which we assume is primarily via denitrification. Light functioned as a limiting resource for primary productivity. From low to high light conditions, annual NPP increased 177 to 430 g C?m?2?y?1 and retention of N isotope tracer increased from 50 to 65% as a result of increased retention in plants. Nitrate leaching losses were low overall and were not affected by light levels. Light availability regulated the fate of N inputs and unfertilized lawns may function as substantial sinks for reactive N through storage in the terrestrial system and N loss by denitrification. However, whether or not denitrification is generally an N sink will depend on the ratio of non-reactive (i.e., N2) to reactive (i.e., N2O, NO) denitrification products. Overall, we find that effective strategies for managing N sources and sinks in cities will likely need to consider light availability, particularly in systems receiving water subsidies via irrigation. 相似文献
84.
Kyle?T.?MartinsEmail author Andrew?Gonzalez Martin?J.?Lechowicz 《Urban Ecosystems》2017,20(6):1359-1371
The role of urban expansion on bee diversity is poorly understood, but it may play an important role in restructuring pollinator diversity observed in rural regions at the urban perimeter. We studied bee communities in two habitats essential for pollinators (residential gardens and semi-natural areas) at 42 sites situated at the edge of greater Montreal, Canada. Bee species richness, abundance and functional diversity all increased with urbanization in both habitat types, but gardens and semi-natural areas supported distinct bee communities with unique responses to urbanization in terms of species turnover. Compared to semi-natural sites, residential gardens supported bees that foraged from a greater number but a lower proportion of available plant species. Bees did not discriminate between exotic and indigenous plant species in either gardens or semi-natural sites and were attracted to flowers in either habitat irrespective of their origins. Protecting semi-natural ruderal areas and providing residential garden habitats for pollinators are both effective means of promoting regional bee diversity in urbanizing regions. 相似文献
85.
Shanna K. Kattari N. Eugene Walls Stephanie Rachel Speer 《Journal of social work in disability & rehabilitation》2017,16(2):116-140
Transgender and gender nonconforming (GNC) individuals frequently experience discrimination and potentially a lack of respect from service providers, suggesting they have decreased access to professionals with cultural competency. Similarly, people with disabilities experience higher levels of discrimination in social services than their nondisabled counterparts. From an intersectional perspective, this study examines rates of discrimination in accessing social services faced by transgender and GNC people, comparing across ability. Data indicate that although transgender and GNC individuals of all abilities experience gender-based discrimination when accessing social services, those with disabilities experience higher levels of antitransgender discrimination in mental health centers, rape crisis centers, and domestic violence shelters. 相似文献
86.
John W. Creswell Rachel C. Sinley 《KZfSS K?lner Zeitschrift für Soziologie und Sozialpsychologie》2017,69(2):87-105
With much of the development of mixed methods occurring through the works of scholars from the US, the UK, Canada, and the Anglos-Saxon/English-speaking countries, the discourse about a global research community must consider how it needs to be sensitive to diverse cultures. Clearly, the discussion must focus on adapting mixed methods to best fit the problems of countries, the cultural norms of conducting research, and the scholarly talents of in-country investigators. Unfortunately, the mixed methods literature is largely silent on diverse cultural adaptations of mixed methods.In this article, we first trace the involvement of worldwide countries in the historic development of mixed methods. Then, to gain a better understanding of the use and adaptation of mixed methods in diverse world academic cultures, we provide a qualitative study of themes mentioned by participants from seven different countries. From both the historical overview and the qualitative study, we end by making suggestions about specific strategies for a global discourse about mixed methods research, and suggest a de-colonizing presence of the Anglo-Saxon/English-speaking countries in the global expansion of mixed methods. 相似文献
87.
Previous research suggests that an increasing age at first marriage has contributed to the prevalence of sexual hookups on U.S. college campuses. In this article, we use life course and marital horizons theories to analyze the influence of ideal age at first marriage on hooking up among unmarried heterosexual college students. Analyses of the Online College Social Life Survey (N = 17,981) show a positive association between ideal age at first marriage and hookups for most students, but not for students whose mothers have no post‐secondary education, Asian men, Asian women, and Latina women. Variation in ideal marriage timing does not account for gender, racial/ethnic, and class gaps in hookup participation. Results are discussed with reference to the role of sexuality in processes of stratification throughout young adulthood. 相似文献
88.
Rachel Goldhill 《Journal of Social Work Practice》2017,31(3):279-292
This paper reports on a PhD study, investigating the supervision of women service users (WSUs), by probation officers (POs) based on video data of one-to-one supervision sessions. The research identifies competing agendas of probation in England and Wales – one side emphasises punishment, whilst the other encourages humanistic, relationship-based practices. POs, routinely juggling these opposing expectations, appreciate traditional probation values of giving the WSU a voice and embracing psychodynamic approaches, to provide structure and support in confronting the complexities of officer/service user interactions. However, the data show that driven by managerialist enforcement requirements, it is the punitive discourse which is more frequently translated into practice. Organisational pressures, feelings about the person opposite, the offence or the individual’s background can manifest as conscious or unconscious micro-messages or masking messages. Just as SUs put on masks to disguise negative emotions or feel powerful, so too do POs; POs recognise masks and deceptions in SUs and, similarly, SUs are aware of this dynamic with POs. The research identifies practitioner ambivalence to certain narratives, particularly sexual abuse or poor mental health and, it is argued, reflective supervision is needed to deconstruct difficult personal and professional issues. 相似文献
89.
Over the twentieth and twenty-first centuries, veterans have been more likely to enter into race/ethnic intermarriages than non-veterans. Theories of race/ethnic intermarriage variously point to how minority race/ethnicity, race/ethnically diverse social settings, progressive racial attitudes, and high socioeconomic status increase individuals’ likelihood of intermarrying. Veterans’ unique racial and socioeconomic characteristics may contribute to their greater likelihood of intermarrying relative to non-veterans: larger percentages of veterans than non-veterans are members of racial and ethnic minority groups, while military service increases individual service members’ long-term economic and educational prospects. At the same time, veterans share in common their exposure to the unique military environment, which may increase their likelihood of intermarriage by diversifying their social circles, and subjecting their attitudes and behavior to group norms that are more explicitly egalitarian than those of society at large. The present study considers these two possible explanations for veterans’ greater likelihood of intermarriage. We use data on seven cohorts of men over six decades in the Current Population Survey, representing a total of 1,456,742 observations, to decompose the difference in likelihood of racial intermarriage between veterans and non-veterans among married men aged 18–65. We find that across cohorts and decades, veterans’ greater likelihood of intermarrying is not fully explained by their race/ethnic and socioeconomic composition. We argue that veterans’ greater likelihood of intermarrying may therefore be driven by their exposure to the military environment. 相似文献
90.
Giulio?CapernaEmail authorView authors OrcID profile Giovanna?Boccuzzo 《Social indicators research》2018,136(3):1071-1088
The aim of this work is to propose a tool for measuring a complex concept, and to apply it to big sets of data measured on ordinal and/or dichotomous scales. An important field of application are subjective data, that are often based on opinions or personal evaluations. Many national and international surveys employ this kind of data, measured among thousand of individuals. Thanks to the use of the “average rank” as a synthetic measure of a complex concept, we believe that poset theory could be a very useful approach for dealing with ordinal data avoiding the use of scaling procedures. Because classic poset approaches are at their best when applied to few data at a time, our idea is based on a procedure for sampling units from a big population using a simple criterion to summarize the resulting values appropriately. Applying the central limit theorem enables a comparison of the results obtained from different groups using statistical tests on the means. We used our Height of Groups by Sampling (HOGS) method to compare the average rank among groups that are defined by one or more socio-demographic variables influencing the level of the complex concept we wish to measure. The application of the HOGS procedure to life satisfaction in Italy generated convincing results, revealing significant differences between regions, genders and levels of formal education. We compared the results given by HOGS with the non linear principal component analysis and obtain an easy readable output with convincing precision and accuracy; we are confident that the HOGS procedure can be applied to many other concepts investigated in the social sciences. 相似文献