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11.

Context

The conservation value of residential landscapes is becoming increasingly apparent in our urbanizing world. The ecological characteristics of residential areas are largely determined by the decisions of many individual “managers.” In these complex socio-ecological systems, it is important to understand the factors that motivate human decision-making.

Objectives

Our first objective was to quantify wildlife resources and management activities in residential landscapes and compare vegetation in front and back yards. Our second objective was to test three hypotheses linked with variation in yards: socioeconomic characteristics, neighborhood design factors, and perceptions of neighborhood birds.

Methods

We conducted surveys of over 900 residents in 25 Chicago-area neighborhoods to examine the wildlife resources contained in front and back yards and the social factors associated with variation in yards. We used a multi-scalar approach to examine among-yard and among-neighborhood variation in residential landscapes.

Results

Results indicate that back yards contain more wildlife resources than front yards, including greater vegetation complexity, more plants with fruit/berries, and more plants intended to attract birds. Furthermore, different hypotheses explain variation in front and back yards. Perceptions of birds were most important in explaining variation in back yard vegetation and wildlife-friendly resources per parcel, while neighbors’ yards and socioeconomic characteristics best explained front yard vegetation.

Conclusions

This study demonstrates the importance of back yards as an unexplored and underestimated resource for biodiversity. In addition, the results provide insight into the complex factors linked with yard decisions, notably that residents’ connections with neighborhood birds appear to translate to on-the-ground actions.
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Electrical conductivity in the precambrian lithosphere of western canada   总被引:1,自引:0,他引:1  
The subcrustal lithosphere underlying the southern Archean Churchill Province (ACP) in western Canada is at least one order of magnitude more electrically conductive than the lithosphere beneath adjacent Paleoproterozoic crust. The measured electrical properties of the lithosphere underlying most of the Paleoproterozoic crust can be explained by the conductivity of olivine. Mantle xenolith and geological mapping evidence indicate that the lithosphere beneath the southern ACP was substantially modified as a result of being trapped between two nearly synchronous Paleoproterozoic subduction zones. Tectonically induced metasomatism thus may have enhanced the subcrustal lithosphere conductivity of the southern ACP.  相似文献   
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There is a wide range of technical measures to improve the efficiency of fuel use in industry. The economic justification for adopting these measures can, as a rule, be readily established. If one can resolve the nontechnoeconomic constraints which affect the adoption of these measures, one can look forward to substantial reductions in the fuel required to operate many important industrial processes.  相似文献   
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When confronted with a novel familial disorder, veterinarians should consult McKusick's catalogue of inherited disorders in humans, called Mendelian Inheritance in Man (MIM), or its online version (OMIM), to see whether a similar disorder has been reported in humans. They should also consult the other readily available sources of comparative information on mice and domesticated species. Increasingly, such consultations can be conducted on the Internet via the World Wide Web. If it is thought that an animal disorder is homologous with a human disorder, publications describing the animal disorder should include the MIM number(s) for that disorder. Future research can then test the hypothesis of homology, until a consensus is reached.  相似文献   
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