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221.
222.
Cat Button Maria Adelaida Antonette Mias-Mamonong Bernhard Barth Jonathan Rigg 《Local Environment》2013,18(6):705-722
Sorsogon City is a rapidly urbanising coastal area in the Philippines. Its location, combined with a rapidly changing and growing urban fabric, leaves it vulnerable to both incremental climate change and associated extreme weather events. In this paper, UN-HABITAT data are used to draw out the climate change vulnerabilities and policy responses in Sorsogon City. Vulnerability “hotspots” highlight the spatial intersection of socio-economic justice concerns, particularly in terms of vulnerability to increased cyclone activity. We discuss vulnerabilities of Sorsogon City and its citizens to climate change and measures undertaken through various social, environmental and technical systems and interventions to increase resilience. The paper also attempts to unpick the relationship between the neat, concise reported city and the complexities of urban life using the Sorsogon experiment to consider the limitations of such approaches to governing climate change. We group these under four headings: social simplification in the absence of data; over-governance (and under-representation); quick wins versus strategic investment; and stretching the ecological and vulnerability footprints of the city. The experience of Sorsogon City is then extended to reflect on issues of governance and planning in other Asian coastal cities. 相似文献
223.
Daniel A. Marion Jonathan D. Phillips Chad Yocum James Jahnz 《Journal of the American Water Resources Association》2019,55(6):1425-1442
Factors influencing sediment availability are assessed and erosion rates are quantified for an off‐highway vehicle (OHV) trail system in the Ouachita Mountains of Arkansas. As of May 2012, the Wolf Pen Gap trail system included 77.0 km of "trails" which consist of county roads; open and closed Forest Service roads; and open and closed OHV trails. For a given trail length, the sediment volume available to be eroded is determined by bare trail width and sediment depth. Four condition types are defined that group trail sections based on statistically different trail widths or depths. Trail construction method appears to influence sediment availability differences more than erosion potential (as indexed by trail slope gradient and length). The range for annual trail erosion rates is estimated as 75 and 210 tonne/ha/yr. The high and low rates are obtained using two independent methods. The 210 tonne/ha/yr rate is computed from mean sediment capture at 30 sediment traps installed for 0.5–1.0 year. The 75 tonne/ha/yr rate is computed assuming all available trail sediment measured in a one‐time sampling is eroded over the next year. We argue in support of this assumption and suggest both rate values may be conservative. Trail erosion rates and sediment trap observations indicate frequent trap cleanout will be needed to continue sediment capture from All Terrain Vehicle trails. 相似文献
224.
Joseph Tzanopoulos Jonathan Mitchley John D. Pantis 《Agriculture, ecosystems & environment》2007,120(2-4):370-376
This case study on the Sifnos island, Greece, assesses the main factors controlling vegetation succession following crop abandonment and describes the vegetation dynamics of maquis and phrygana formations in relation to alternative theories of secondary succession. Field survey data were collected and analysed at community as well as species level. The results show that vegetation succession on abandoned crop fields is determined by the combined effects of grazing intensity, soil and geological characteristics and time. The analysis determines the quantitative grazing thresholds that modify the successional pathway. Light grazing leads to dominance by maquis vegetation while overgrazing leads to phryganic vegetation. The proposed model shows that vegetation succession following crop abandonment is a complex multi-factor process where the final or the stable stage of the process is not predefined but depends on the factors affecting succession. An example of the use of succession models and disturbance thresholds as a policy assessment tool is presented by evaluating the likely vegetation impacts of the recent reform of the Common Agricultural Policy on Sifnos island over a 20–30-year time horizon. 相似文献
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226.
A synergetic model for implementing an integrated management system: an empirical study in China 总被引:4,自引:0,他引:4
The implementation and certification of quality, environmental and occupational health and safety management systems have become a priority for many organizations. They are viewed as symbol for success and prerequisite for survival. However, it has been proved to be difficult to operate multiple parallel management systems covering quality, environment, and occupational health and safety and to ensure their alignment with the organization's strategy. To investigate the current status of integrated management system (IMS), a structured questionnaire survey was administrated. It is concluded that the major problems for enterprises to operate multiple parallel management systems include: it causes complexity of internal management, it lowers management efficiency, it incurs cultural incompatibility, it causes employee hostility, and increases management costs. The survey also examined the internal and external factors that affect the implementation of IMS. The internal factors include: (1) human resources, (2) organizational structure, (3) company culture, and (4) understanding and perception. The external factors consist of: (1) technical guidance, (2) certification bodies, (3) stakeholders and customers, and (4) the institutional environment. The article proposes a multi-level synergy model (strategic synergy, organizational structural-resource-cultural synergy, and documentation synergy) for an effective implementation of IMS. 相似文献
227.
228.
Classification of Ephemeral,Intermittent, and Perennial Stream Reaches Using a TOPMODEL‐Based Approach 下载免费PDF全文
Tanja N. Williamson Carmen T. Agouridis Christopher D. Barton Jonathan A. Villines Jeremiah G. Lant 《Journal of the American Water Resources Association》2015,51(6):1739-1759
Whether a waterway is temporary or permanent influences regulatory protection guidelines, however, classification can be subjective due to a combination of factors, including time of year, antecedent moisture conditions, and previous experience of the field investigator. Our objective was to develop a standardized protocol using publically available spatial information to classify ephemeral, intermittent, and perennial streams. Our hypothesis was that field observations of flow along the stream channel could be compared to results from a hydrologic model, providing an objective method of how these stream reaches can be identified. Flow‐state sensors were placed at ephemeral, intermittent, and perennial stream reaches from May to December 2011 in the Appalachian coal basin of eastern Kentucky. This observed flow record was then used to calibrate the simulated saturation deficit in each channel reach based on the topographic wetness index used by TOPMODEL. Saturation deficit values were categorized as flow or no‐flow days, and the simulated record of streamflow was compared to the observed record. The hydrologic model was more accurate for simulating flow during the spring and fall seasons. However, the model effectively identified stream reaches as intermittent and perennial in each of the two basins. 相似文献
229.
Andrew Turner Nimisha Singh Jonathan P. Richards 《Environmental pollution (Barking, Essex : 1987)》2009,157(5):1526-1532
Fragments of antifouling paint and environmental geosolids have been sampled from the island of Malta and analysed for total and bioaccessible metals. Total concentrations of Ba, Cd, Cu, Pb, Sn and Zn were two to three orders of magnitude higher in spent antifouling composites relative to respective values in background soils and road dusts. Paint fragments were visible in geosolids taken from the immediate vicinity of boat maintenance facilities and mass balance calculations, based on Ba as a paint tracer, suggested that the most contaminated soils, road dusts and boatyard dusts contained about 1%, 7% and 9%, respectively, of antifouling particles. Human bioaccessibilities of metals were evaluated in selected samples using a physiologically based extraction technique. Accessibilities of Cd, Cu, Pb and Zn in the most contaminated solids were sufficient to be cause for concern for individuals working in the boat repair industry and to the wider, local community. 相似文献
230.
The fate and transport of antibiotics in natural water systems is controlled in part by interactions with nanometer (10−9 m) metal oxide particles. Experiments were performed by mixing solutions of ampicillin (AMP), a common, penicillin-class human and veterinary antibiotic, with 25 nm-TiO2 (anatase) nanoparticles at different pH conditions. Both sorption and degradation of AMP were observed in the AMP-nanoparticle solutions. For AMP concentrations from ∼3 μM to 2.9 mM the overall AMP removal from solution can be described by linear isotherms with removal coefficients (Kr) of 3028 (±267) L kg−1 at pH 2, 11,533 (±823) L kg−1 at pH 4, 12,712 (±672) L kg−1 at pH 6, and 1941 (±342) L kg−1 at pH 8. Mass spectral analysis of AMP solutions after removal of the solid nanoparticles yielded ions that indicate the presence of peniclloic acid, penilloic acid and related de-ammoniated by-products as possible compounds resulting from the degradation of AMP at the TiO2 surface. 相似文献