Good Governance of land and natural resources : Balancing local and global interests

This report presents the results of a seminar on ‘good governance of land and natural resources; balancing local and global interests’. Three case studies were presented on large-scale land acquisitions, biofuels – fuelling development in Brazil and governance of the mineral sector in Eastern DRC. Participants identified 6 important challenges for improving land and natural resource governance and concluded that: more research and information sharing is needed; collaborative voluntary and legally binding initiatives are needed at international level to balance local and global interests; accountability arrangements need to be set up that enable stakeholders to hold each other accountable; capacity building of all actors is needed and that each actor has its own contributions to make to good governance

Social Learning and Networking : How multiple actors can learn through joint analysis, dialogue and co-creation

We are facing complex societal problems such as climate change, human conflict, poverty and inequality, and need innovative solutions. Multi-stakeholder processes (MSPs) are more and more seen as a critical way of coming to such innovative solutions. It is thought that when multiple stakeholders are able to meet, share experiences, learn together and contribute to decisions, new and innovative ways of dealing with problems are found and turned into action. Still, much remains to be understood about the role and effectiveness of social learning in multi-stakeholder settings. This report summarizes the deliberations of the seminar “Social learning and networking: How multiple actors can learn through joint analysis, dialogue and co-creation”, which was held in Wageningen on 16 September 2010

Critical points of maximal D=8 gauged supergravities

We study the general deformations of maximal eight-dimensional supergravity by using the embedding tensor approach. The scalar potential induced by these gaugings is determined. Subsequently, by combining duality covariance arguments and algebraic geometry techniques, we find the complete set of critical points of the scalar potential. Remarkably, up to SO(2) X SO(3) rotations there turns out to be a unique theory admitting extrema. The gauge group of the theory is CSO(2,0,1).Comment: 14 pages. v2: minor changes - published versio

Les 25 Résolutions de Konni

Niger is the largest exporter of onions in West Africa. More than 100.000 Nigerian peasants cultivate onions. For them and all the other operators within the chain (intermediaries, tradesmen, shipping agents), the onion is an important source of income. SNV Niger, and Wageningen UR Centre for Development Innovation in the Netherlands, in collaboration with FCMN Niya and Agri-Bilan, initiated an action research titled “Peeling the onion”. The goal of this action-research is to identify possibilities of collective action for all the actors in the value chain of the onion. The research focusses on ‘leverages’ to induce changes which make the onion subsector in one time more competitive, inclusive and sustainable. After this first phase, we shared our results during this participative workshop in Birni Konni in the area of Tahoua. Moreover one stimulated the dialogue between the various actors within the value chain of the onion resulting in the 25 resolutions of Konni! This report is the result of this workshop and dialogues

Charting the landscape of N=4 flux compactifications

We analyse the vacuum structure of isotropic Z_2 x Z_2 flux compactifications, allowing for a single set of sources. Combining algebraic geometry with supergravity techniques, we are able to classify all vacua for both type IIA and IIB backgrounds with arbitrary gauge and geometric fluxes. Surprisingly, geometric IIA compactifications lead to a unique theory with four different vacua. In this case we also perform the general analysis allowing for sources compatible with minimal supersymmetry. Moreover, some relevant examples of type IIB non-geometric compactifications are studied. The computation of the full N=4 mass spectrum reveals the presence of a number of non-supersymmetric and nevertheless stable AdS_4 vacua. In addition we find a novel dS_4 solution based on a non-semisimple gauging.Comment: Minor corrections and references added. Version published in JHE

Utility of different data types for calibrating flood inundation models within a GLUE framework

International audienceTo translate a point hydrograph forecast into products for use by environmental agencies and civil protection authorities, a hydraulic model is necessary. Typical one- and two-dimensional hydraulic models are able to predict dynamically varying inundation extent, water depth and velocity for river and floodplain reaches up to 100 km in length. However, because of uncertainties over appropriate surface friction parameters, calibration of hydraulic models against observed data is a necessity. The value of different types of data is explored in constraining the predictions of a simple two-dimensional hydraulic model, LISFLOOD-FP. For the January 1995 flooding on the River Meuse, The Netherlands, a flow observation data set has been assembled for the 35-km reach between Borgharen and Maaseik, consisting of Synthetic Aperture Radar and air photo images of inundation extent, downstream stage and discharge hydrographs, two stage hydrographs internal to the model domain and 84 point observations of maximum free surface elevation. The data set thus contains examples of all the types of data that potentially can be used to calibrate flood inundation models. 500 realisations of the model have been conducted with different friction parameterisations and the performance of each realisation has been evaluated against each observed data set. Implementation of the Generalised Likelihood Uncertainty Estimation (GLUE) methodology is then used to determine the value of each data set in constraining the model predictions as well as the reduction in parameter uncertainty resulting from the updating of generalised likelihoods based on multiple data sources

Gauged N=4 supergravities

We present the gauged N=4 (half-maximal) supergravities in four and five spacetime dimensions coupled to an arbitrary number of vector multiplets. The gaugings are parameterized by a set of appropriately constrained constant tensors, which transform covariantly under the global symmetry groups SL(2) x SO(6,n) and SO(1,1) x SO(5,n), respectively. In terms of these tensors the universal Lagrangian and the Killing Spinor equations are given. The known gaugings, in particular those originating from flux compactifications, are incorporated in the formulation, but also new classes of gaugings are found. Finally, we present the embedding chain of the five dimensional into the four dimensional into the three dimensional gaugings, thereby showing how the deformation parameters organize under the respectively larger duality groups.Comment: 36 pages, v2: references added, comments added, v3: published version, references added, typos corrected, v4: sign mistakes in footnote 4 and equation (2.13) correcte

Stable de Sitter vacua in N=2, D=5 supergravity

We find 5D gauged supergravity theories exhibiting stable de Sitter vacua. These are the first examples of stable de Sitter vacua in higher-dimensional (D>4) supergravity. Non-compact gaugings with tensor multiplets and R-symmetry gauging seem to be the essential ingredients in these models. They are however not sufficient to guarantee stable de Sitter vacua, as we show by investigating several other models. The qualitative behaviour of the potential also seems to depend crucially on the geometry of the scalar manifold.Comment: 26 pages, v2:typos corrected, published versio

Refined topological amplitudes in N=1 flux compactification

We study the implication of refined topological string amplitudes in the supersymmetric N=1 flux compactification. They generate higher derivative couplings among the vector multiplets and graviphoton with generically non-holomorphic moduli dependence. For a particular term, we can compute them by assuming the geometric engineering. We claim that the Dijkgraaf-Vafa large N matrix model with the beta-ensemble measure directly computes the higher derivative corrections to the supersymmetric effective action of the supersymmetric N=1$ gauge theory.Comment: 16 pages, v2: reference adde