Convergent finite element approximations for problems of near-incompressible and near-inextensible transversely isotropic linear elasticity

This work comprises a detailed theoretical and computational study of the boundary value problem for transversely isotropic linear elastic bodies. The main objective is the development and implementation of low-order finite element methods that are uniformly convergent in the incompressible and inextensible limits. The first step in the investigation is a study of the constitutive relation for transversely isotropic elasticity, and establishment of conditions on the five material parameters under which the relation is pointwise stable. This forms the basis for a study of well-posedness of the weak displacement-based formulation. Conforming finite element approximations are studied. The error estimate indicates the possibility of extensional locking; on the other hand, anisotropy, measured as the ratio of Young’s moduli in the fibre and transverse directions, plays a role in minimizing or even eliminating volumetric locking behaviour. Extensional locking is circumvented with the use of selective under-integration, in the context of low-order quadrilateral elements. Its equivalence with mixed and perturbed Lagrangian methods are shown. A series of numerical results illustrates the various features of the formulations considered. In a second approach, interior penalty or discontinuous Galerkin (DG) formulations of the problem are considered. Low-order approximations on triangles are adopted, with the use of three interior penalty discontinuous Galerkin methods, viz. nonsymmetric, symmetric and incomplete. It is known that these methods are uniformly convergent in the incompressible limit for the case of isotropy. This property carries over to the transversely isotropic case for moderate anisotropy. An error estimate suggests the possibility of extensional locking, and under-integration of the extensional edge terms is proposed as a remedy. This modification is shown to lead to an error estimate that is consistent with locking-free behaviour. Numerical tests confirm the uniformly convergent behaviour, at an optimal rate, of the under-integrated scheme

Impacts of Community Forest Management and strictly protected areas on deforestation and human well-being in Madagascar

Protected areas and Community Forest Management (CFM) are among the most widespread interventions to conserve forests in tropical countries. In addition to their impacts on forests and the biodiversity they contain, these interventions also affect human well-being, particularly that of the local communities who are often poor and politically marginalized and whose livelihoods depend directly on the forest resources being conserved. To develop effective interventions, practitioners need to have credible, strong and scientifically rigorous evidence on their impacts on forests (or the biodiversity they contain) and human well-being. However, while cientifically rigorous impact evaluation of programs is well advanced in fields such as development, health and education, it is rare in nature conservation. The rare existing studies focus mostly on protected areas and other interventions, such as CFM, are relatively untouched by scientifically rigorous impact evaluation. Different challenges account for the limited adoption of rigorous impact evaluation in nature conservation. Among these are the identification and elimination of rival explanations: factors other than the intervention that can explain the observed relationship between the intervention and the outcome. Potential rival explanations are factors that can confound impact estimates by affecting both assignment of units to intervention and the outcome. Another potential rival explanation is baseline outcome data that should have been collected before the intervention was implemented. Baseline data are often missing in conservation studies. Another challenge is the heterogeneity of management practices within and units exposed to the same intervention. A challenge pertaining particularly to studies on human well-being impacts is the multi-dimensional nature of human well-being. In this thesis, I aim to investigate the impacts of different conservation interventions on environmental and human well-being outcomes while addressing the challenges to conservation impact evaluation discussed above. My case studies are CFM and strict protection in Madagascar; one of the world’s hottest biodiversity hotspots. I have three specific objectives which are addressed in three manuscripts with the following titles: i) Effectiveness of CFM at reducing deforestation across Madagascar (manuscript 1): With colleagues, I investigated the impacts of CFM on deforestation at the national scale between 2000 and 2010 using matching to control for factors confounding impact estimates. We did not detect an impact of CFM, on average, when CFM areas were compared to non-CFM areas, even when the sample was restricted to only where information suggests effective CFM implementation on the ground. However, impacts were heterogeneous conditional on whether CFM permits commercial use of forest resources. No CFM impact was detected where commercial use of natural resources is allowed. However, we did detect some reduction of deforestation in areas managed under CFM that does not permit commercial use, when compared to non-CFM or CFM permitting commercial use. Our findings suggest differentiating among types of CFM is important for estimating the impacts of this conservation approach. ii) Impacts of CFM on human economic well-being across Madagascar (manuscript 2): In this manuscript, we investigated impacts on household living standards across Madagascar as measured by per capita consumption expenditure. We used matching to control for confounding factors and addressed the issue of missing baseline values of household consumption expenditures using an approach known as the placebo test. We cannot statistically reject the hypothesis of zero impact, but we can credibly reject the hypothesis that CFM has had substantial negative impacts on economic well-being across CFM communities in Madagascar. There were heterogeneous impacts, with a mixture of positive and negative impacts, conditional on household proximity to forest and education level. In conclusion, the impacts of CFM vary with household characteristics: some may lose while others may gain. iii) The potential of the Global Person Generated Index (GPGI) for evaluating the perceived impact of conservation interventions on subjective well-being (manuscript 3): In this study, we used the GPGI, a subjective and multidimensional well-being instrument, to investigate the relative impacts of strict protection and CFM on human well-being in sites in eastern Madagascar. We used a participatory approach to establish the cause-effect relationship between the interventions and the outcomes (i.e., to eliminate rival explanations). We did not detect statistically significant difference, on average, between the two approaches in three measures we used to examine the magnitude of their relative impacts on subjective well-being. However, we found some differences in the characteristics of subjective well-being component domains impacted by the strict protection and CFM and in the priority domains that could be targeted by increased resource allocation to improve well-being in locally meaningful ways. Combined with the participatory approach to establish cause-effect relationship, we suggest GPGI provides highly relevant insight that can be used to design policy seeking to increase local participation and develop more positive local attitudes towards conservation. The first two manuscripts (1 and 2) involve analyses at the national scale, objective indicators (deforestation and consumption expenditure) and rigorous quantitative causal inference designs making them of value to external stakeholders, such as government agencies and donors, seeking to know the magnitude of impacts to inform large scale conservation policy. However, these large scale studies may be of limited use for project managers who want to build locally legitimate interventions or those who want a deeper understanding of how conservation interventions affect local people. In the third manuscript, we used a subjective measure of well-being (the GPGI) in combination with participatory approach to establish cause-effect relationship between interventions and locally meaningful outcomes. This has limited value for quantitatively measuring the magnitude of impacts; but holds some promises for project managers who seek local participation and social sustainability. Conservation has long suffered from poor quality evaluation of its impacts. This thesis shows that methods for impact evaluation are available, but the appropriate method that should be applied depends, among other things, on the purpose of the evaluation

New density estimates of a threatened sifaka species (Propithecus coquereli) in Ankarafantsika National Park

Propithecus coquereli is one of the last sifaka species for which no reliable and extensive density estimates are yet available. Despite its endangered conservation status [IUCN, 2012] and recognition as a flagship species of the northwestern dry forests of Madagascar, its population in its last main refugium, the Ankarafantsika National Park (ANP), is still poorly known. Using line transect distance sampling surveys we estimated population density and abundance in the ANP. Furthermore, we investigated the effects of road, forest edge, river proximity and group size on sighting frequencies, and density estimates. We provide here the first population density estimates throughout the ANP. We found that density varied greatly among surveyed sites (from 5 to ∼100 ind/km2) which could result from significant (negative) effects of road, and forest edge, and/or a (positive) effect of river proximity. Our results also suggest that the population size may be ∼47,000 individuals in the ANP, hinting that the population likely underwent a strong decline in some parts of the Park in recent decades, possibly caused by habitat loss from fires and charcoal production and by poaching. We suggest community-based conservation actions for the largest remaining population of Coquerel's sifaka which will (i) maintain forest connectivity; (ii) implement alternatives to deforestation through charcoal production, logging, and grass fires; (iii) reduce poaching; and (iv) enable long-term monitoring of the population in collaboration with local authorities and researchers.Optimus!Alive- IGC fellowship, FCT fellowship: (SFRH/BD/64875/2009), University of Mahajanga, Groupement de Recherche International (GDRI), "Laboratoire d'Excellence" (LABEX) entitled TULIP (ANR-10-LABX-41), the Rufford Small Grant Foundation grant: (10941-1)

Impacts of forests on children’s diet in rural areas across 27 developing countries

Micronutrient deficiency affects about a third of the world’s population. Children in developing countries are particularly vulnerable. Consequences include impaired cognitive and physical development and increased childhood morbidity and mortality. Recent studies suggest that forests help alleviate micronutrient deficiency by increasing dietary diversity. However, evidence is mostly based on weakly designed local case studies of limited relevance to global policies. Furthermore, impacts of forests on diet vary among communities, and understanding this variation can help target actions to enhance impact. We compile data on children’s diets in over 43,000 households across 27 developing countries to examine the impacts of forests on dietary diversity. We use empirical designs that are attentive to assumptions necessary for causal interpretations and that adequately account for confounding factors that could mask or mimic the impact. We find that high exposure to forests causes children to have at least 25% greater dietary diversity compared to lack of exposure, a result comparable to the impacts of some nutrition-sensitive agricultural programs. A closer look at a subset of African countries indicates that impacts are generally higher for less developed communities, but highest with certain access to markets, roads, and education. Our results also indicate that forests could help reduce vitamin A and iron deficiencies. Our study establishes the causal relationship between forests and diet and thus strengthens the evidence for integrating forest conservation and management into nutrition interventions. Our results also suggest that providing households some access to capital can increase the impact of forest-related interventions on nutrition

Influences des Pressions Anthropiques sur les Lémuriens d’Anantaka, dans la Partie Est du Plateau de Makira, Maroantsetra, Madagascar

L’équipe de Groupe d’Etude et de Recherche sur les Primates de Madagascar (GERP), pour contribuer dans la protection, a prospecté et suivi 12 sites dans la forêt de Makira dont Anantaka pendant les mois de septembre et octobre 2005 et 2006. A l’aide des lignes - inventaire, la densité relative de la population de lémuriens a été obtenue par des observations directes tandis que les pressions humaines ont été inventoriées par l‘évaluation des surfaces d‘incidence des activités humaines. Des activités anthropiques sur les lémuriens ont été identifiées. Les influences de chaque type de pression sur les espèces de Lémuriens (trois diurnes strictes, une cathémérale et dix nocturnes) répertoriées à travers 12 sites ont été analysées à partir du coefficient de corrélation R de Spearman entre chaque facteur menaçant par rapport à chaque effectif de lémurien. Ainsi, d’une part, on a déduit que le site d’Anantaka, avec ses 14 espèces lémuriennes, est le plus riche en espèces de lémuriens. Et d’autre part, on a constaté que plus le nombre de village est abondant et plus leur distance par rapport à la forêt est rapprochée et que les impacts de pression sur l’écosystème forestier augmente avec des activités relatives comme la chasse, les coupes illicites, les défrichements de la forêt primaire, les défrichements des forêts secondaires et la transformation des forêts en tavy ou en kijana (prairie) ainsi que les exploitations minières illicites. A part cette dégradation de la biodiversité, la décadence de la moralité à la fois sur les notions du civisme et le concept du fady (tabou) en l’encontre des Aye aye par exemple, se trouve sur une situation bouleversante, puisque les gens ne considèrent plus ni les valeurs culturelles pour la conservation de la forêt ni les lois régissant la gestion forestière et les chasses des animaux sauvages. Ces critères classifient le site d’Anantaka dans la cible focale de conservation du fait que la couverture forestière d’Anantaka présente encore 75 % de forêt, 25 % est transformée en savoka et en prairie. C’est ainsi que l’indispensablement d’une priorité en matière de conservation des lémuriens pour conserver la niche écologique exceptionnelle d’Anantaka. La conservation de Makira serait optimale avec l’intégration de la population riveraine du site d’Anantaka dans la gestion rationnelle de leurs ressources naturelles et avec l’intervention de l’éducation environnementale dans quelques localités dont les Communautés de base (COBA) et avec l’appui technique émanant des associations dans l’élaboration d’un plan de développement touchant surtout l’agriculture et d’un projet qui assurera la surveillance et le contrôle du secteur par des missions de suivi - évaluation

Forest Conservation: A Potential Nutrition-Sensitive Intervention in Low- and Middle-Income Countries

Rasolofoson, Ricketts, Jacob, Johnson, Pappinen and Fisher. Childhood undernutrition yearly kills 3.1 million children worldwide. For those who survive early life undernutrition, it can cause motor and cognitive development problems that translate into poor educational performance and limited work productivity later in life. It has been suggested that nutrition-specific interventions (e.g., micronutrient supplementation) that directly address the immediate determinants of undernutrition (e.g., nutrient intake) need to be complemented by nutrition-sensitive interventions that more broadly address the underlying determinants of undernutrition (e.g., food insecurity). Here, we argue that forest conservation represents a potentially important but overlooked nutrition-sensitive intervention. Forests can address a number of underlying determinants of undernutrition, including the supply of forest food products, income, habitat for pollinators, women\u27s time allocation, diarrheal disease, and dietary diversity. We examine the effects of forests on stunting—a debilitating outcome of undernutrition—using a database of household surveys and environmental variables across 25 low- and middle-income countries. Our result indicates that exposure to forest significantly reduces child stunting (at least 7.11% points average reduction). The average magnitude of the reduction is at least near the median of the impacts of other known nutrition interventions. Forest conservation interventions typically cover large areas and are often implemented where people are vulnerable, and thus could be used to reach a large number of the world\u27s undernourished communities that may have difficult access to traditional nutrition programs. Forest conservation is therefore a potentially effective nutrition-sensitive intervention. Efforts are needed to integrate specific nutrition goals and actions into forest conservation interventions in order to unleash their potential to deliver nutritional benefits