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101.
Landscape‐scale alterations that accompany urbanization may negatively affect the population structure of wildlife species such as freshwater turtles. Changes to nesting sites and higher mortality rates due to vehicular collisions and increased predator populations may particularly affect immature turtles and mature female turtles. We hypothesized that the proportions of adult female and immature turtles in a population will negatively correlate with landscape urbanization. As a collaborative effort of the Ecological Research as Education Network (EREN), we sampled freshwater turtle populations in 11 states across the central and eastern United States. Contrary to expectations, we found a significant positive relationship between proportions of mature female painted turtles (Chrysemys picta) and urbanization. We did not detect a relationship between urbanization and proportions of immature turtles. Urbanization may alter the thermal environment of nesting sites such that more females are produced as urbanization increases. Our approach of creating a collaborative network of scientists and students at undergraduate institutions proved valuable in terms of testing our hypothesis over a large spatial scale while also allowing students to gain hands‐on experience in conservation science.  相似文献   
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New global initiatives to restore forest landscapes present an unparalleled opportunity to reverse deforestation and forest degradation. Participatory monitoring could play a crucial role in providing accountability, generating local buy in, and catalyzing learning in monitoring systems that need scalability and adaptability to a range of local sites. We synthesized current knowledge from literature searches and interviews to provide lessons for the development of a scalable, multisite participatory monitoring system. Studies show that local people can collect accurate data on forest change, drivers of change, threats to reforestation, and biophysical and socioeconomic impacts that remote sensing cannot. They can do this at one‐third the cost of professionals. Successful participatory monitoring systems collect information on a few simple indicators, respond to local priorities, provide appropriate incentives for participation, and catalyze learning and decision making based on frequent analyses and multilevel interactions with other stakeholders. Participatory monitoring could provide a framework for linking global, national, and local needs, aspirations, and capacities for forest restoration.  相似文献   
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This article brings to light one aspect of alternative agri-food practices by exploring the values and meanings domestic food producers associate with their actions, thereby making a small contribution to increasing understanding of the act of urban backyard food production. While Australian backyards have long been productive spaces, there has been little examination of this phenomenon in the Australian context. Limited quantitative data give some insight into the extent of domestic production, and while there is an increasing interest in certain aspects of the local food system, including community gardens and farmers markets, there is a dearth of literature that explores the contemporary act of domestic production. This work seeks to situate the act of domestic production within the broader movement calling for change within the global food system, particularly that being articulated by the food sovereignty movement. Drawing on Gibson–Graham's diverse economies framework, and through interviews with eight domestic food producers in one Australian city, this work finds that the act of growing food at home offers space for hope – where small acts can be seen as part of the broader food sovereignty movement seeking to remake our food system.  相似文献   
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Standard evaluations of air quality models rely heavily on a direct comparison of monitoring data matched with the model output for the grid cell containing the monitor's location. While such techniques may be adequate for some applications, conclusions are limited by such factors as the sparseness of the available observations (limiting the number of grid cells at which the model can be evaluated) and the incommensurability between volume-averages and pointwise observations. We examine several sets of simulations to illustrate the effect of incommensurability in a variety of cases distinguished by the type and extent of spatial correlation present. Block kriging, a statistical method which can be used to address the issue, is then demonstrated using the simulations. Lastly, we apply this method to actual data and discuss the practical importance of understanding the impact of spatial correlation structure and incommensurability.  相似文献   
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National surveys and a survey conducted by the authors in March and April 2004 revealed that the public’s concerns about air, water and land pollution have declined during the last four years in the United States and more specifically in the State of New Jersey. In New Jersey pollution remains a major concern of most residents, even during a period of a war, anxiety about terrorism and the economy. Those most anxious about pollution do not believe that government is doing enough to protect the environment, want to maintain current environmental laws, and are worried about the future. Disproportionately they are African and White Americans, middle income, and college graduates, in other words, part of the American mainstream. Direct attempts to weaken environmental protection are likely to be resisted by this core of the population, which does not trust current federal, state and local governments to protect the environment. We expect concerns for the environment to continue and yet change as production processes in the United States continue a trend toward pollution prevention, and we wait for the public’s mental models to catch up with this evolving reality.  相似文献   
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