329 research outputs found
Review of river fisheries valuation in West and Central Africa
This paper provides a review of the valuation of river fisheries in West and Central Africa. It is the general perception that, compared to the biological and ecological aspects of river fisheries, this particular subject area has received relatively little attention. Economic valuation is concerned with finding expression for what is important in life for human society. It should, therefore, be a central and integral part of government decision-making and policy. The review started with concepts and methods for valuation. Three main types of valuation techniques were identified: conventional economic valuations, economic impact assessments and socioeconomic investigations, and livelihood analysis. On the basis of a literature review, valuation information was then synthesized for the major regional river basins and large lakes, and also used to develop a series of national fisheries profiles. To supplement this broad perspective, a series of case studies are also presented, which focus in particular on the impact of changes in water management regime. Finally, the paper presents an assessment of the three main types of valuation methodology and a set of conclusions and recommendations for future valuation studies
Incorporating fish market and trade information into policy making for sustainable livelihood and poverty reduction: Methods and lessons for the Lake Chad basin
Densities and age structure of fished versus protected populations of Queen Conch (Strombus gigas L.) in the Turks & Caicos Islands
Participatory diagnosis and adaptive management of small-scale fisheries in the Niger River Basin
In a broad sense, analysis of âresilienceâ is about the capacity of systems to adapt to
shocks, recognizing that disturbance and change are integral component of complex
systems. More formally, resilience analysis proposes to focus on mechanisms and
processes that help systems absorbing perturbations and shocks, and coping with
uncertainty and risks. Defined in such a way, the concept of resilience thus appears
particularly useful for the management of small-scale fisheries. However, while the
resilience concept is appealing, particularly in the face of the failure of current
management approaches, the danger is that it remains largely academic and theoretical,
and not of a great help in effectively improving the way natural resources are managed
on the ground. The challenge, therefore, lies in a pragmatic approach to operationalizing
the concept of resilience and making its implementation on the ground practical and
meaningful. In this project we propose a framework aimed at this objective and we test
it in the specific context of small-scale fisheries in the Niger River Basin
The Role of Fatalism in Resilience to Food Price Volatility in Bangladesh
Millions of people in Bangladesh suffer from hunger, unpredictable and unstable livelihoods, precarious living conditions and social injustice. Yet they survive and become resilient. However, the resilience achieved by the poor is minimal and incremental in nature and does not result in their wellbeing. Based on three years of qualitative research, this article attempts to understand the nature of and pathways to âresilience of the poor people'. The article argues that poor people's approach to âresilienceâ is twofold. First, they perceive their poverty and associated problems as âAllah's will', with not much to be done about it. At the same time, they engage in continuous innovative practices to survive. These two worldviews together ('fatalismâ and âself?help') make the poor âresilient'. This also âpartiallyâ explains the absence of strong activism, collective action and protests within a context of state failure (in terms of ensuring rights and entitlements to its citizens)
Experimental demonstration of quantum correlations over more than 10 km
Energy and time entangled photons at a wavelength of 1310 nm are produced by
parametric downconversion in a KNbO3 crystal and are sent into all-fiber
interferometers using a telecom fiber network. The two interferometers of this
Franson-type test of the Bell-inequality are located 10.9 km apart from one
another. Two-photon fringe visibilities of up to 81.6 % are obtained. These
strong nonlocal correlations support the nonlocal predictions of quantum
mechanics and provide evidence that entanglement between photons can be
maintained over long distances.Comment: 5 pages, REVTeX, 3 postscript figures include
Inner structure of the Puy de DËome volcano: cross-comparison of geophysical models (ERT, gravimetry, muon imaging)
International audienceMuon imaging of volcanoes and of geological structures in general is actively being developed by several groups in the world. It has the potential to provide 3-D density distributions with an accuracy of a few percent. At this stage of development, comparisons with established geophysical methods are useful to validate the method. An experiment has been carried out in 2011 and 2012 on a large trachytic dome, the Puy de DËome volcano, to perform such a comparison of muon imaging with gravimetric tomography and 2-D electrical resistivity tomography. Here, we present the preliminary results for the last two methods. North-south and east-west resistivity profiles allow us to model the resistivity distribution down to the base of the dome. The modelling of the Bouguer anomaly provides models for the density distribution within the dome that are directly comparable with the results from the muon imaging. Our ultimate goal is to derive a model of the dome using the joint interpretation of all sets of data
Metrics to analyze and improve diets through food Systems in low and Middle Income Countries
Taking a food systems approach is a promising strategy for improving diets. Implementing such an approach would require the
use of a comprehensive set of metrics to characterize food systems, set meaningful goals, track food system performance, and
evaluate the impacts of food system interventions. Food system metrics are also useful to structure debates and communicate to
policy makers and the general public. This paper provides an updated analytical framework of food systems and uses this to
identify systematically relevant metrics and indicators based on data availability in low and middle income countries. We
conclude that public data are relatively well available for food system drivers and outcomes, but not for all of the food system
activities. With only minor additional investments, existing surveys could be extended to cover a large part of the required
additional data. For some indicators, however, targeted data collection efforts are needed. As the list of indicators partly overlaps
with the indicators for the Sustainable Development Goals (SGDs), part of the collected data could serve not only to describe and
monitor food systems, but also to track progress towards attaining the SDGs
Conceptualising COVID-19âs impacts on household food security
COVID-19 undermines food security both directly, by disrupting food systems, and indirectly, through the impacts of lockdowns
on household incomes and physical access to food. COVID-19 and responses to the pandemic could undermine food production,
processing and marketing, but the most concerning impacts are on the demand-side â economic and physical access to food. This
paper identifies three complementary frameworks that can contribute to understanding these effects, which are expected to persist
into the post-pandemic phase, after lockdowns are lifted. FAOâs âfour pillarsââ availability, access, stability and utilisation â and
the âfood systemsâ approach both provide holistic frameworks for analysing food security. Senâs âentitlementâ approach is useful
for disaggregating demand-side effects on household production-, labour-, trade- and transfer-based entitlements to food.
Drawing on the strengths of each of these frameworks can enhance the understanding of the pandemicâs impacts on food security,
while also pinpointing areas for governments and other actors to intervene in the food system, to protect the food security of
households left vulnerable by COVID-19 and public responses
Air shower simulation for background estimation in muon tomography of volcanoes
International audienceOne of the main sources of background for the radiography of volcanoes using atmospheric muons comes from the accidental coincidences produced in the muon telescopes by charged particles belonging to the air shower generated by the primary cosmic ray. In order to quantify this background effect, Monte Carlo simulations of the showers and of the detector are developed by the TOMUVOL collaboration. As a first step, the atmospheric showers were simulated and investigated using two Monte Carlo packages, CORSIKA and GEANT4.We compared the results provided by the two programs for the muonic component of vertical proton-induced showers at three energies: 1, 10 and 100 TeV. We found that the spatial distribution and energy spectrum of the muons were in good agreement for the two codes
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