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121.
Japan’s national park system constitutes a potentially viable mechanism for securing local community participation and building stakeholder consensus for sustainable park management, although the potential of this system is yet to be fully maximized. This article gives an overview of the system of protecting natural resources in Japan, focusing on the national park system. Parks are managed by zoning and regulation, which is unique in that land is not “set aside” for nature conservation, but designated as national park wherever the need to preserve “scenic beauty” has been recognized, regardless of land ownership or land use. Although resource conservation under this system has been problematic, it has advantages, especially in terms of community participation. This article demonstrates that in order to reach the system’s potential, the park authority must act as coordinator of stakeholders and facilitator of bottom-up approaches to decision-making. In order to do this, steps that must be taken include the following: identifying the various stakeholders in park management and defining the “local community”; clarifying the roles and responsibilities of each stakeholder; and supporting consensus-building among stakeholders regarding the objectives and long-term vision of each park. By taking these steps, it would be possible to build a park management system that overrides government boundaries and involves local communities. This will enable the park authority to address the challenges facing Japan’s complex system of conserving natural resources, and move towards sustainable management of natural resources in Japan.  相似文献   
122.
Copper based catalysts supported on mesoporous materials, which were in turn based on a surfactant expanded zirconium phosphate for the formation of silica galleries in the interlayer space, were prepared by the impregnation method. They were then characterised and tested in the selective catalytic reduction of NO with ammonia as active catalysts for the control of the NOx emissions from heavy duty vehicles. Copper catalysts displayed a high catalytic performance, even in the presence of 14% (v/v) of H2O and 100 ppm of SO2. They also displayed improved catalytic behaviour when compared to a CuZSM5 catalyst.  相似文献   
123.
Daily averaged atmospheric concentrations and dry deposition fluxes of particulate metals were measured seasonally at six urban sites and one non-urban coastal site in the Los Angeles region using a conventional total suspended particulate matter (TSP) filter, surrogate surface deposition plates, and a Noll Rotary Impactor (NRI), which provides information about particle size distribution in four size ranges above 6 μm. With the exception of the non-urban site, particulate metal concentrations and deposition fluxes were remarkably uniform spatially and temporally. At all sites there were significant metal concentrations on particles greater than 10 μm, a commonly used upper limit for many air quality monitoring studies, and these large particles were estimated to be responsible for most of the deposited mass of metals. Annual averaged values of deposition rates measured with a surrogate surface were in good agreement with values estimated using theoretical deposition velocities in conjunction with measured size-segregated particle concentrations. Image analysis of particles deposited on NRI stage A, which collects all particles greater than 6 μm, indicated nighttime metal concentrations and deposition at the non-urban coastal site was higher than in the day time due to offshore advection of urban air associated with the diurnal land breeze. Measured enrichments of crustal elements and metals were correlated, indicating efficient mixing of natural and anthropogenic material from different sources, hypothesized to be the result of cyclical resuspension and deposition of dust by moving vehicles and wind.  相似文献   
124.
The cyanobacterial cytotoxin cylindrospermopsin (CYN) has become increasingly common in fresh waters worldwide. It was originally isolated from Cylindrospermopsis raciborskii in Australia; however, in European waters, its occurrence is associated with other cyanobacterial species belonging to the genera Aphanizomenon and Anabaena. Moreover, cylindrospermopsin-producing strains of widely distributed C. raciborskii have not yet been observed in European waters. The aims of this work were to assess the occurrence of CYN in lakes of western Poland and to identify the CYN producers. The ELISA tests, high-performance liquid chromatography (HPLC)-DAD, and HPLC-mass spectrometry (MS)/MS were conducted to assess the occurrence of CYN in 36 lakes. The cyrJ, cyrA, and pks genes were amplified to identify toxigenic genotypes of cyanobacteria that are capable of producing CYN. The toxicity and toxigenicity of the C. raciborskii and Aphanizomenon gracile strains isolated from the studied lakes were examined. Overall, CYN was detected in 13 lakes using HPLC-MS/MS, and its concentrations varied from trace levels to 3.0 μg?L?1. CYN was widely observed in lakes of western Poland during the whole summer under different environmental conditions. Mineral forms of nutrients and temperature were related to CYN production. The molecular studies confirmed the presence of toxigenic cyanobacterial populations in all of the samples where CYN was detected. The toxicity and toxigenicity analyses of isolated cyanobacteria strains revealed that A. gracile was the major producer of CYN.  相似文献   
125.
This paper presents an agile participatory urban soundscape planning process model, which is proposed as a prerequisite on which to build and reference the efficacy of urban soundscape planning. The model was developed through data synthesis and analysis and mapping engagement with diverse stakeholders across four applied soundscape projects in Brighton and Hove, UK. To the best of the authors’ knowledge, the model is the first of its kind in applied soundscape practice. The data was collected through semi-structured interviews with key stakeholders and document analysis of published resources. The framework used for the analysis of the findings comprised four core urban planning stages: goals and objectives, engagement (e.g. prediction/modelling/design/planning), implications, evaluation. The study found that when integrating soundscape planning with core urban planning stages it was necessary to first identify the appropriate stakeholders in relation to the project context. It was found that these stakeholders could be wide-ranging and unexpected, thereby reinforcing the appropriateness of incorporating an agile approach in the resulting model. The study also found that users’ perceptions are central to soundscape practice and need to be considered at each stage of a planning process to produce an effective and sustainable outcome. A variety of specific events, appropriate to the requirements of the stakeholders, are important for engaging planning authorities, users and other stakeholders at different stages. This study also demonstrated that an evidence-based evaluation method is recommended in an agile participatory urban soundscape planning process to assess stakeholders’ engagement at each stage and to inform and guide subsequent steps in the planning process relevant to the local context(s).  相似文献   
126.
127.
Polychlorinated biphenyls (PCBs) were measured in the air and water over the Hudson River Estuary during six intensive field campaigns from December 1999 to April 2001. Over-water gas-phase SigmaPCB concentrations averaged 1100 pg/m3 and varied with temperature. Dissolved-phase SigmaPCB concentrations averaged 1100 pg/L and displayed no seasonal trend. Uncertainty analysis of the results suggests that PCBs with 5 or fewer chlorines exhibited net volatilization. The direction of net air/water exchange could not be determined for PCBs with 6 or more chlorines. Instantaneous net fluxes of SigmaPCBs ranged from +0.2 to +630 ng m(-2) d(-1). Annual fluxes of SigmaPCBs were predicted from modeled gas-phase concentrations, measured dissolved-phase concentrations, daily surface water temperatures and wind speeds. The net volatilization flux was +62 microg m(-2) yr(-1), corresponding to an annual loss of +28 kg/yr of SigmaPCBs from the Hudson River Estuary for the year of 2000.  相似文献   
128.
Planetary Stewardship in an Urbanizing World: Beyond City Limits   总被引:1,自引:0,他引:1  
Cities are rapidly increasing in importance as a major factor shaping the Earth system, and therefore, must take corresponding responsibility. With currently over half the world’s population, cities are supported by resources originating from primarily rural regions often located around the world far distant from the urban loci of use. The sustainability of a city can no longer be considered in isolation from the sustainability of human and natural resources it uses from proximal or distant regions, or the combined resource use and impacts of cities globally. The world’s multiple and complex environmental and social challenges require interconnected solutions and coordinated governance approaches to planetary stewardship. We suggest that a key component of planetary stewardship is a global system of cities that develop sustainable processes and policies in concert with its non-urban areas. The potential for cities to cooperate as a system and with rural connectivity could increase their capacity to effect change and foster stewardship at the planetary scale and also increase their resource security.  相似文献   
129.
Insecticides have long been used as the main method in limiting agricultural pests, but their widespread use has resulted in environmental pollution, development of resistances, and biodiversity reduction. The effects of insecticides at low residual doses on both the targeted crop pest species and beneficial insects have become a major concern. In particular, these low doses can induce unexpected positive (hormetic) effects on pest insects, such as surges in population growth exceeding what would have been observed without pesticide application. Methomyl and chlorpyrifos are two insecticides commonly used to control the population levels of the cotton leafworm Spodoptera littoralis, a major pest moth. The aim of the present study was to examine the effects of sublethal doses of these two pesticides, known to present a residual activity and persistence in the environment, on the moth physiology. Using a metabolomic approach, we showed that sublethal doses of methomyl and chlorpyrifos have a systemic effect on the treated insects. We also demonstrated a behavioral disruption of S. littoralis larvae exposed to sublethal doses of methomyl, whereas no effects were observed for the same doses of chlorpyrifos. Interestingly, we highlighted that sublethal doses of both pesticides did not induce a change in acetylcholinesterase activity in head of exposed larvae.  相似文献   
130.
We conducted stable 13C and 15N analysis on white shark vertebrae and demonstrated that incremental analysis of isotopes along the radius of a vertebral centrum produces a chronological record of dietary information, allowing for reconstruction of an individual's trophic history. Isotopic data showed significant enrichments in 15N with increasing sampling distance from the centrum center, indicating a correlation between body size and trophic level. Additionally, isotopic values verified two distinct ontogenetic trophic shifts in the white shark: one following parturition, marking a dietary switch from yolk to fish; and one at a total length of >341 cm, representing a known diet shift from fish to marine mammals. Retrospective trophic-level reconstruction using vertebral tissue will have broad applications in future studies on the ecology of threatened, endangered, or extinct species to determine life-long feeding patterns, which would be impossible through other methods.  相似文献   
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