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411.
International institutions, understood as sets of rules contained in international agreements, are aimed at orienting national
governments towards specific policy options. Nevertheless, they can determine a change in national policies and practices
only if states are willing and capable of incorporating international obligations into their national legislations and ensuring
their application and enforcement in areas that follow completely under national jurisdiction. The establishment of marine
protected areas promoted by international agreements as a tool for the protection of marine resources represents an interesting
case for revealing the complex interactions between international institutions and national actors. Particularly, the establishment
of these areas in Senegal shows the salience of domestic constellations of actors who may support or undercut national commitments
to international regimes: political elites, bureaucracies, the general public and target groups. By anchoring the empirical
analysis to an actor-centred institutionalist perspective, the article explains how dynamic constellations of actors can distort
the penetration of international objectives in the national policy framework. Different constellations of national actors
can indeed bend international institutions at different moments: during the formulation of a new law in line with international
obligations; in the definition of its implementation framework; and in the enforcement of national policies. 相似文献
412.
The number of MPAs has increased sharply, from just 118 in 1970 to well over 6,300 today. This growth in numbers has also been accompanied by a voluminous growth in the academic literature on the theme, with writers employing ecologic, economic and governance lenses (or a combination thereof) to both support the case for MPA creation, and to evaluate just how successfully (or not) existing MPAs match up to their promises. Research suggests effective management of such protected areas is vital if desired outcomes are to be achieved within the allotted time period. This Special Feature on MPAs therefore seeks to address two key questions derived from the management effectiveness framework of Hockings and others (2000), namely: ‘How appropriate are the management systems and processes in place?’ and ‘Were the desired Objectives achieved—and if so, why?’ Fourteen articles, drawing on different disciplinary perspectives relating to MPA experiences from across the globe, offers insights into these questions by considering, inter alia, how: are MPA sites selected?; is ‘buy-in’ to the process from the various stakeholders achieved?; are these stakeholder’s views reflected in the management systems that evolve?, and what monitoring and evaluation mechanisms are in place? Bringing these perspectives and approaches together through the medium of this Special Feature is thus intended to further our understanding of the different issues that may confront both planners and managers of Marine Protected Areas. 相似文献
413.
This study addresses the effect of political transition and subsequent timber bans on forest loss in Myanmar, in the context of identified drivers. Cook’s Distance (CD) was applied to remotely sensed time-series forest loss dataset to measure the effect of the events. Forest loss derived fragmentation metrics were linked to drivers at a landscape scale. Results show that at the national level, the political transition in 2011 had maximum effect (CD 0.935) on forest loss while the timber bans decreased forest loss by 612.04 km2 and 213.15 km2 in 2015 and 2017 (CD 0.146 and 0.035), respectively. The effect of the events varied for different States/Regions. The dominant drivers of change shifted from plantations in 2011 to infrastructure development in 2015. This study demonstrates the effects of policy on forest loss at various scales and can inform decision-makers for forest conservation, planning and development of mitigation measures. 相似文献
414.
415.
Mission assurance policy and risk management are essential in enabling decision makers to ensure successful completion of missions by addressing the security status of cyber assets. This paper presents a novel mission assurance policy that adapts to the dynamic security status of all mission assets to quickly and automatically determine mission assurance level and to decide what changes are needed accordingly. The novelty of this mission assurance policy stems from using a time Petri net model for determining the security status of cyber assets, and then employing binary or multi-valued logic decision diagrams to assess the mission assurance level. The ability of a mission assurance policy to successfully complete its objectives depends mainly on whether a risk management scheme is provided to reduce risk to an acceptable level. To that end, this paper also describes a risk management scheme to systematically deal with the main factors of risk management such as the temporal interdependencies of cyber assets, impact of attacks, and risk mitigation. Given that the status of cyber assets changes due to the dynamic cybersecurity environment of asset vulnerabilities, threats, and recovery, the proposed mission assurance policy and risk management scheme enable decision makers to cope with the real-time assessment of mission assurance level. 相似文献
416.
Forest Management Devolution: Gap Between Technicians’ Design and Villagers’ Practices in Madagascar 总被引:1,自引:0,他引:1
Fanny Rives Stéphanie M. Carrière Pierre Montagne Sigrid Aubert Nicole Sibelet 《Environmental management》2013,52(4):877-893
In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems. 相似文献
417.
Rubio-Gutierrez Juan Carlos Mendez-Hernández Pablo Guéguen Yann Galichon Pierre Tamayo-Ortiz Marcela Haupt Karsten Medeiros Mara Barbier Olivier Christophe 《Environmental science and pollution research international》2022,29(21):31042-31058
Environmental Science and Pollution Research - Bone mass in adulthood depends on growth and mineralization acquired during childhood and adolescence. It is well known that these stages of life are... 相似文献
418.
Philippe Vidon Pierre‐Andre Jacinthe Xiaoqiang Liu Katelin Fisher Matthew Baker 《Journal of the American Water Resources Association》2014,50(3):639-652
Little is known about the impact of agricultural legacy on subsurface biogeochemical processes in the years following restoration of riparian wetlands (WLs). More knowledge is also needed on the relative importance of seasons, precipitation events, and inputs of water and nutrients driving nitrogen (N), phosphorus (P), sulfur (S), and greenhouse gas (GHG) (N2O, CO2, CH4) dynamics in these systems. This investigation of a riparian zone comprising a restored WL area and a nonrestored well‐drained alluvium (AL) area in the United States Midwest revealed that despite successful hydrological restoration a decade earlier, biogeochemical conditions in the WL area remained less anoxic than in natural WLs, and not significantly different from those in the AL area. No significant differences in N, P, S, and C compound concentrations or fluxes were observed between the AL and WL areas. Over the duration of the study, nitrate (NO3?) and soluble reactive phosphorus appeared to be primarily driven by hillslope contributions. Ammonium (NH4+), sulfate (SO42?), and CO2 responded strongly to seasonal changes in biogeochemical conditions in the riparian zone, while N2O and CH4 fluxes were most influenced by large rewetting events. Overall, our results challenge overly simplistic assumptions derived from direct interpretation of redox thermodynamics, and show complex patterns of solutes and GHGs at the riparian zone scale. 相似文献
419.
Diagnosis of abiotic and biotic stress factors using the visible symptoms in foliage 总被引:1,自引:0,他引:1
Vollenweider P Günthardt-Goerg MS 《Environmental pollution (Barking, Essex : 1987)》2006,140(3):562-571
Visible symptoms in the foliage of trees are recorded to monitor the effects of abiotic and biotic stress. Difficulties are reported in diagnosing the origin of stress. The present paper discusses several diagnostic criteria which are usable in different species for a better determination of the stress factor type. A new diagnosis scheme to differentiate between classes of abiotic and biotic stress factors is supplied. Abiotic stress generates gradients of symptoms. The symptom specificity is determined by the degree of interaction between the stress factor and plant defense system. Symptoms caused by abiotic stress and natural autumnal senescence can be morphologically different or undistinguishable according to the stress and plant species. With biotic stress, the class of parasitic is generally recognizable on the basis of the visible symptoms. Structurally and physiologically based explanations of the symptom morphology are still missing for many stress factors. 相似文献
420.
Sophie Grima Véronique Bellon-Maurel Françoise Silvestre Pierre Feuilloley 《Journal of Polymers and the Environment》2001,9(1):39-48
A new test method is described for assessing biodegradation of plastic material under simulated soil conditions. An inert substrate can be activated with soil extract and nutrient and used in place of soil in biodegradation tests. The biodegradation level is evaluated by determining the carbon dioxide (CO2) production released by the test reactors. Effects of substrate nature, solution pH, nutrient composition, soil extract concentration, and activation duration on CO2 production were investigated, and the experimental conditions were optimized. Results obtained with cellulose showed a biodegradation rate of 80% within 28 days. Moreover, with this kind of substrate, reaction products and residues can be easily extracted and analysed. 相似文献