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Environmental Science and Pollution Research - Atmospheric pollutants, such as NOx, SO2, and particulate matter, together with water percolation inside the stone pores, represent the main causes of...  相似文献   
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Deer support high tick intensities, perpetuating tick populations, but they do not support tick-borne pathogen transmission, so are dilution hosts. We test the hypothesis that absence of deer (loss of a dilution host) will result in either an increase or a reduction in tick density, and that the outcome is scale dependent. We use a complementary methodological approach starting with meta-analysis, followed up by a field experiment. Meta-analysis indicated that larger deer exclosures reduce questing (host-seeking) tick density, but as the exclosure becomes smaller (<2.5 ha) the questing tick density is increased (amplified). To determine the consequences for tick-borne pathogen transmission we carried out a field experiment, comparing the intensity of ticks that fed on hosts competent for tickborne pathogen transmission (rodents) in two small (<1 ha) deer exclosures and their replicated controls. Intensity of larval ticks on rodents was not significantly different between treatments, but nymph intensity, the tick stage responsible for tick-borne encephalitis (TBE) transmission, was higher in deer exclosures. TBE seropositive rodents were found in a deer exclosure but not in the controls. We propose that localized absence of deer (loss of a dilution host) increases tick feeding on rodents, leading to the potential for tick-borne disease hotspots.  相似文献   
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Adaptive management as applied to tourism policy treats management policies as experiments that probe the responses of the system as human behavior changes. We present a conceptual systems model that incorporates the gap between observed and desired levels of the ecological footprint with respect to biocapacity. Addressing this gap (or 'overshoot') can inform strategies to increase or decrease visitation or its associated consumption in the coming years. The feedback mechanism in this conceptual model incorporates a gap between observed and desired ecological footprint levels of tourists and residents. The work is based on longer-term and ongoing study of tourism impacts and ecological footprint assessments from the SPIN-Eco Project. We present historical tourism and environmental data from the province of Siena, Italy and discuss the use of discrete, static environmental indicators as part of an iterative feedback process to manage tourism within biophysical limits. We discuss a necessary shift of emphasis from certain and static numbers to a process-based management model that can reflect slow changes to biophysical resources. As underscored by ecological footprint analysis, the energy and material use associated with tourism and local activity can erode natural capital foundations if that use exceeds the area's biological capacity to support it. The dynamic, and iterative process of using such indicators as management feedback allows us to view sustainability more accurately as a transition and journey, rather than a static destination to which management must arrive.  相似文献   
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An analytical method, using supercritical fluid extraction (SFE), was assessed for residue analysis of the insecticides fipronil, acrinathrin and pyridaben and the fungicide kresoxim-methyl in melons. Extraction conditions were optimized on glass beads, as inert material, evaluating different pressures, temperatures, and CO(2) volumes. Also, the extractability of pesticides from hydromatrix and anhydrous magnesium sulfate was evaluated. Both adsorbents were evaluated for the preparation of SFE-spiked melon samples. Extractions of fortified samples were done using 20 mL of CO(2), 300 atm, and 50 degrees C. Different extraction conditions, including the addition of water and methanol as a static modifier, were used to assess the extractability of these pesticides, and the addition of methanol was demonstrated to improve the extraction of all the studied pesticides.  相似文献   
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Urbanization has rapidly increased in recent decades and the negative effects on biodiversity have been widely reported. Urban green areas can contribute to improving human well-being, maintaining biodiversity, and ecosystem services (e.g. pollination). Here we examine the evolution of studies on plant–pollinator interactions in urban ecosystems worldwide, reviewing also research funding and policy actions. We documented a significant increase in the scientific production on the theme in recent years, especially in the temperate region; tropical urban ecosystems are still neglected. Plant–pollinator interactions are threatened by urbanization in complex ways, depending on the studied group (plant or pollinator [generalist or specialist]) and landscape characteristics. Several research opportunities emerge from our review. Research funding and policy actions to pollination/pollinator in urban ecosystems are still scarce and concentrated in developed countries/temperate regions. To make urban green spaces contribute to the maintenance of biodiversity and the provision of ecosystem services, transdisciplinary approaches (ecological–social–economic–cultural) are needed.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01410-z) contains supplementary material, which is available to authorized users.  相似文献   
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