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1.
This paper discusses some of the challenges and opportunities that can arise when implementing ecosystem-based management (EBM) in tropical nations. EBM creates a new series of challenges, problems, and opportunities that must be considered in light of existing governance and management frameworks in a local context. The paper presents five case studies from different parts of the tropical world, including Oceania, insular and continental Southeast Asia, East Africa, and the Caribbean, which illustrate that the implementation of EBM in watershed and marine ecosystems offers a new series of challenges and opportunities for its inclusion with existing forms of environmental governance and management. The paper suggests that EBM is best thought of as an expansion of customary management (CM) and integrated coastal management (ICM), rather than a paradigm shift, and that it has certain benefits that are worth integrating into existing systems when possible. The paper concludes that the cultural and institutional context of CM as well as the experience, technical skills, and legal basis that serve ICM programs are logical platforms from which to build EBM programs. Some guidelines for creating hybrid management regimes are suggested. In sum, declining marine species and ecosystems require urgent action, necessitating utilization of existing paradigms such as ICM and CM as a foundation for building EBM.  相似文献   
2.
The effect of salinity on the concentration of metals in Spartina alterniflora tissues and excreted salts and the distribution of metals between these compartments was tested in a greenhouse experiment. S. alterniflora stems were planted in pots of dredge sediment that was amended with a suite of six metals (Cd, Cr, Cu, Ni, Pb, and Zn). The overlying water of individual pots was maintained at treatment salinities of 0, 15, or 30 practical salinity units. The proportion of total metal distributed to the tissues and excreted salt of S. alterniflora was not significantly influenced by salinity for any of the metals. The concentration of Pb in root and leaf tissues and in excreted salt was influenced by salinity, as was the concentration of Zn in root tissue and excreted salt. Contrary to expectations, the concentration of Pb and Zn in excreted salts decreased as salinity increased. Although the influence of salinity on the concentration of Pb and Zn in S. alterniflora tissue has not been previously reported, the influence of salinity on the tissue concentrations of Pb agrees with previous research on dicots.  相似文献   
3.
Islands are known to be vulnerable to natural hazards, resulting in substantial risks for their tourism industries. To facilitate the systematic analysis of the underlying vulnerability drivers, a tourism disaster vulnerability framework was developed. The conceptual model then guided qualitative empirical research in three regions: the Caribbean, the South Pacific, and the Indian Ocean. The results from 73 interviews highlight common, as well as idiosyncratic, factors that shape the islands’ hazardscapes and vulnerabilities. Key vulnerabilities included social, economic, political, and environmental dimensions. Probably, the most critical vulnerability driver is the lack of private sector investment in disaster risk reduction. This is interrelated with deficient planning processes, on-going demand for coastal products, lack of political will, and poor environmental conditions. Notwithstanding many barriers, some businesses and organisations engage proactively in addressing disaster risk. The paper’s empirical evidence supports the validity of the framework, and suggestions for further research are made.  相似文献   
4.
The Large Marine Ecosystem (LME) concept is widely established as a large-scale approach to coastal and marine management. LME-oriented activities have focused mainly on natural sciences. Socioeconomic and governance aspects have only recently been receiving increased attention. The 64 LMEs that have been defined appeared to exhibit considerable diversity in characteristics that would be expected to affect governability. This paper explores two questions: (1) Do the LMEs vary widely enough in geopolitical complexity that different approaches to governance may be required for different LMEs? (2) Are there groups of LMEs within which one might take similar approaches to governance? The analysis demonstrates that there is considerable heterogeneity among LMEs with regard to characteristics that would be expected to affect governability. It concludes that a diversity of governance approaches will be required to cope with this heterogeneity. It also appears that LMEs can be grouped according to these characteristics. This suggests that different approaches could be considered for clusters rather than for individual LMEs and that there can be sharing of experience and learning within clusters. The types of relationships between features of LMEs and the ‘best’ approaches to marine governance are discussed in the context of emerging governance ideas.  相似文献   
5.
The ionospheric electric field has been measured in the E region above the Churchill auroral research range under quiet and under disturbed conditions. Results were obtained 112 and 212 hr before local midnight over an altitude range of 115–165 km. The instruments and analysis differ from those used by other workers. An unusually advantageous vehicle motion resulted in dipole measurements along the magnetic field being modulated by the vehicle motion. Under quiet conditions and in the presence of a diffuse, east-west 2 kR auroral arc, the predominant vector component of the electric field was also quiet and between 35 and 40 mVm perpendicular to the magnetic field, southward. Parallel to the magnetic field, the vector component increased from ?17 mV/m at 130 km, reversed direction at 160 km during the latter third of the flight and fluctuated around + 6 mV/m between 155 and 135 km on the descent. Under disturbed conditions during the recovery phase of a large magnetic storm, the electric field was also more disturbed; however, there was no significant electric field along B. Analysis of effects caused when parts of the measurement system are connected by a common magnetic field line, and when one of the probes lies in the wake of the vehicle, shows that measurement perturbations produced by those effects are dominated by the magnetic field line connections and that wake effects are relatively unimportant.  相似文献   
6.
Kingston Harbour is a multi-purpose resource with more than half a million people and a variety of industries on its shores. Primary treated domestic sewage, raw industrial waste and run-off from agricultural land discharge into the bay. Successive surveys since 1968 show a progressive deterioration and the urgent need for a reduction of organic pollution if the benthic fauna is not to be destroyed.  相似文献   
7.
Introducing fishery management planning to Barbados   总被引:1,自引:0,他引:1  
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8.
Anti-poverty politics in Toronto and Mexico City   总被引:1,自引:0,他引:1  
Rianne Mahon 《Geoforum》2010,41(2):209-217
In recent years, governments at different scales in both North and South have been experimenting with alternative methods of alleviating poverty, and redesigning social welfare regimes. While these changes are not entirely congruent across regimes in North and South, there are interesting points of overlap and intersection. The article lays out three broad alternatives to “roll-back” neoliberalism: intrusive liberalism; inclusive liberalism, and a renewed version of social citizenship. It then lays out how these alternatives have played out in anti-poverty politics in Toronto and Mexico City, two sites where creative strategies contesting neoliberalism have been pursued. While both cities occupy a critical place within their respective political economies, they are not usually compared because of their very different positions in the North American division of labour. Yet, as we argue, they face similar challenges in the form of poverty reduction strategies at the national scale that are based on neoliberal principles that do little to meet the needs of their inhabitants. In response, both cities have provided a site for mobilising resources behind alternative anti-poverty policies, inspired by the principles of social citizenship.  相似文献   
9.
The time and temperature stability of various types of magnetic remanence has been measured in pottery samples containing magnetite and in a clay sample containing manganese ferrite. The time decay of rotational remanent magnetization (RRM), anhysteretic remanent magnetization (ARM) and a low-field isothermal remanent magnetization (IRM) has been measured. While the decay of the last two remanences is easily measurable at about 2 and 19 per cent per decade of time, respectively, the decay of RRM is too small to be measured, being less than about 0.1 per cent per decade of time. Thermal demagnetization of thermoremanent magnetization (TRM), ARM and RRM indicates that RRM is also the most thermally stable. The implications of these experiments are that rocks which exhibit gyromagnetic effects such as RRM contain highly stable particles and therefore are likely to be most suitable for palaeomagnetism.  相似文献   
10.
A large marine ecosystem (LME) governance framework, developed from a need to effectively address the sustainable management of the shared living marine resources of the Caribbean, is proposed. The framework is based on four propositions and focuses on a linked examination of two well-known components of LME-level governance: the policy cycle process by which decisions are made and the multi-level nature of LMEs. It accommodates the diversity of policy cycles at multiple levels and the linkages among them required for effective governance of LMEs. The framework takes into account of factors such as context, purpose, jurisdictional scale, capacity and complexity and provides a means to identify critical areas for intervention.  相似文献   
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