851 resultados para ecosystem-based adaptation


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Demands for mechanisms to pay for adaptation to climate risks have multiplied rapidly as concern has shifted from greenhouse gas mitigation alone to also coping with the now-inevitable impacts. A number of viable approaches to how to pay for those adjustments to roads, drainage systems, lifeline utilities and other basic infrastructure are emerging, though untested at the scale required across the nation, which already has a trillion-dollar deferred maintenance and replacement problem. There are growing efforts to find new ways to harness private financial resources via new market arrangements to meet needs that clearly outstrip public resources alone, as well as to utilize and combine public resources more effectively. To date, mechanisms are often seen through a specific lens of scale, time, and method, for example national versus local and public versus market-based means. The purpose here is to integrate a number of those perspectives and also to highlight the following in particular. Current experience with seemingly more pedestrian needs like stormwater management funding is in fact a learning step towards new approaches for broader adaptation needs, using re-purposed but existing fiscal tools. The resources raised from new large-scale market approaches for using catastrophe- and resiliency-bond-derived funds will have their use embodied and operationalized in many separate local and state projects. The invention and packaging of innovative projects—the pre-development phase—will be pivotal to better using fiscal resources of many types. Those efforts can be greatly aided or hindered by larger national and especially state government policy, regulatory and capital market arrangements. Understanding the path to integration of effort across these scales deserves much more attention. Examples are given of how federal, state and local roles are each dimensions of that frontier, how existing tools can apply in new ways and how smart project creation plays a role.

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This paper presents a distributed hierarchical multiagent architecture for detecting SQL injection attacks against databases. It uses a novel strategy, which is supported by a Case-Based Reasoning mechanism, which provides to the classifier agents with a great capacity of learning and adaptation to face this type of attack. The architecture combines strategies of intrusion detection systems such as misuse detection and anomaly detection. It has been tested and the results are presented in this paper.

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Introduction : Une proportion importante des individus ayant recours à des services de réadaptation physique vit avec de la douleur et des incapacités locomotrices. Plusieurs interventions proposées par les professionnels de la réadaptation afin de cibler leurs difficultés locomotrices nécessitent des apprentissages moteurs. Toutefois, très peu d’études ont évalué l’influence de la douleur sur l’apprentissage moteur et aucune n’a ciblé l’apprentissage d’une nouvelle tâche locomotrice. L’objectif de la thèse était d’évaluer l’influence de stimulations nociceptives cutanée et musculaire sur l’acquisition et la rétention d’une adaptation locomotrice. Méthodologie : Des individus en santé ont participé à des séances de laboratoire lors de deux journées consécutives. Lors de chaque séance, les participants devaient apprendre à marcher le plus normalement possible en présence d’un champ de force perturbant les mouvements de leur cheville, produit par une orthèse robotisée. La première journée permettait d’évaluer le comportement des participants lors de la phase d’acquisition de l’apprentissage. La seconde journée permettait d’évaluer leur rétention. Selon le groupe expérimental, l’apprentissage se faisait en présence d’une stimulation nociceptive cutanée, musculaire ou d’aucune stimulation (groupe contrôle). Initialement, l’application du champ de force provoquait d’importantes déviations des mouvements de la cheville (i.e. erreurs de mouvement), que les participants apprenaient graduellement à réduire en compensant activement la perturbation. L’erreur de mouvement moyenne durant la phase d’oscillation (en valeur absolue) a été quantifiée comme indicateur de performance. Une analyse plus approfondie des erreurs de mouvement et de l’activité musculaire a permis d’évaluer les stratégies motrices employées par les participants. Résultats : Les stimulations nociceptives n’ont pas affecté la performance lors de la phase d’acquisition de l’apprentissage moteur. Cependant, en présence de douleur, les erreurs de mouvement résiduelles se trouvaient plus tard dans la phase d’oscillation, suggérant l’utilisation d’une stratégie motrice moins anticipatoire que pour le groupe contrôle. Pour le groupe douleur musculaire, cette stratégie était associée à une activation précoce du muscle tibial antérieur réduite. La présence de douleur cutanée au Jour 1 interférait avec la performance des participants au Jour 2, lorsque le test de rétention était effectué en absence de douleur. Cet effet n’était pas observé lorsque la stimulation nociceptive cutanée était appliquée les deux jours, ou lorsque la douleur au Jour 1 était d’origine musculaire. Conclusion : Les résultats de cette thèse démontrent que dans certaines circonstances la douleur peut influencer de façon importante la performance lors d’un test de rétention d’une adaptation locomotrice, malgré une performance normale lors de la phase d’acquisition. Cet effet, observé uniquement avec la douleur cutanée, semble cependant plus lié au changement de contexte entre l’acquisition des habiletés motrices et le test de rétention (avec vs. sans douleur) qu’à une interférence directe avec la consolidation des habiletés motrices. Par ailleurs, malgré l’absence d’influence de la douleur sur la performance des participants lors de la phase d’acquisition de l’apprentissage, les stratégies motrices utilisées par ceux-ci étaient différentes de celles employées par le groupe contrôle.

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Using a top-down modelling approach, a balanced trophic food web model of a water reservoir of the Ria Formosa lagoonal system was constructed. Few adjustments of input data were necessary to run the model since most of the parameters were estimated at the study site and the characteristics of the water reservoir allowed a high degree of control and precision in terms of sampling and data collection. Trophic levels of the 14 compartments included in the model varied between 1.0 for primary producers and detritus to 3.4 for carnivorous fish and the 14 groups were aggregated in a food chain with six trophic levels. The water reservoir has a detritus based food chain, with the majority of the biomass concentrated in the first two levels, the producers level and the herbivore/detritivore level (97.6%). The transfer efficiencies were low, and decreased with increasing level number, varying between 6.0 and 0.2%. The degree of "ecosystem maturity" was difficult to establish, but several parameters indicate that it could be high. The water reservoir studied, which has similar environmental and ecological characteristics as the Ria Formosa lagoon. is near its carrying capacity. (C) 2004, Elsevier B.V. All rights reserved.

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Marine protected areas (MPAs) are a global conservation and management tool to enhance the resilience of linked social-ecological systems with the aim of conserving biodiversity and providing ecosystem services for sustainable use. However, MPAs implemented worldwide include a large variety of zoning and management schemes from single to multiple-zoning and from no-take to multiple-use areas. The current IUCN categorisation of MPAs is based on management objectives which many times have a significant mismatch to regulations causing a strong uncertainty when evaluating global MPAs effectiveness. A novel global classification system for MPAs based on regulations of uses as an alternative or complementing, the current IUCN system of categories is presented. Scores for uses weighted by their potential impact on biodiversity were built. Each zone within a MPA was scored and an MPA index integrates the zone scores. This system classifies MPAs as well as each MPA zone individually, is globally applicable and unambiguously discriminates the impacts of uses. (C) 2016 The Authors. Published by Elsevier Ltd.

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Legumes are bee-pollinated, but to a different extent. The importance of the plant– pollinator interplay (PPI), in flowering crops such as legumes lies in a combination of the importance of pollination for the production service and breeding strategies, plus the increasing urgency in mitigating the decline of pollinators through the development and implementation of conservation measures. To realize the full potential of the PPI, a multidisciplinary approach is required. This article assembles an international team of genebank managers, geneticists, plant breeders, experts on environmental governance and agro-ecology, and comprises several sections. The contributions in these sections outline both the state of the art of knowledge in the field and the novel aspects under development, and encompass a range of reviews, opinions and perspectives. The first three sections explore the role of PPI in legume breeding strategies. PPI based approaches to crop improvement can make it possible to adapt and re-design breeding strategies to meet both goals of: (1) optimal productivity, based on an efficient use of pollinators, and (2) biodiversity conservation. The next section deals with entomological aspects and focuses on the protection of the “pest control service” and pollinators in legume crops. The final section addresses general approaches to encourage the synergybetweenfoodproductionandpollinationservicesatfarmerfieldlevel.Twobasic approaches are proposed: (a) Farming with Alternative Pollinators and (b) Crop Design System.

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Este trabajo exploratorio estudia al movimiento político Mesa de la Unidad Democrática (MUD), creada con el fin de oponerse la Gobierno socialista existente en venezuela. La crítica que este documento realiza, parte desde el punto de vista de la Ciencia de la Complejidad. Algunos conceptos clave de sistemas complejos han sido utilizados para explicar el funcionamiento y organización de la MUD, esto con el objetivo de generar un diagnóstico integral de los problemas que enfrenta, y evidenciar las nuevas percepciones sobre comportamientos perjudiciales que el partido tiene actualmente. Con el enfoque de la complejidad se pretende ayudar a comprender mejor el contexto que enmarca al partido y, para, finalmente aportar una serie de soluciones a los problemas de cohesión que presen

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Temporary ponds are seasonal wetland habitats subjected to extreme and unstable ecological conditions. Some are classified as priority habitats for conservation by the European Union Habitats Directive. Our study area was the coastal plain of southwest Portugal, which spans across 100km north to south and hosts a large number of temporary ponds as a consequence of climatic and edaphic characteristics. Field sampling of floristic and edaphic data was carried out in 24 temporary ponds every spring between 2005 and 2008. We recorded a total of 174 plant species identified within visually homogeneous plots. We included the data in a geographic information system and classified ponds according to their floristic composition, using a biotic regionalization analysis based on species presence/absence, which is a practical and unambiguous criterion. We found three significantly different groups of ponds which corresponded to an eco-physiognomic pond typology: Mediterranean temporary ponds, marshlands, and disturbed ponds. For the first two pond types we defined characteristic or indicator plant species. We searched also for relationships between pond type and a series of large-scale climatic, geographic, and geological variables, as well as local-scale physical and chemical properties of the soil. Pond type was distinguished by a complex combination of some of these variables, including environmental energy, soil texture, nitrogen content of the soil and pH. A practical way of discriminating between different

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Conservation Agriculture is an ecosystem approach to farming capable of providing solutions for numerous of the agri-environmental concerns in Europe. Certainly, most of the challenges addressed in the Common Agriculture Policy (CAP) could be tackled through Conservation Agriculture (CA). Not only the agri-environmental ones, but also those concerning farmer and rural communities’ prosperity. The optimisation of inputs and similar yields than conventional tillage, make Conservation Agriculture a profitable system compared to the tillage based agriculture. Whereas this sustainable agricultural system was conceived for protecting agrarian soils from its degradation, the numerous collateral benefits that emanate from soil conservation, i.e., climate change mitigation and adaptation, have raised Conservation Agriculture as one of the global emerging agrosciences, being adopted by an increasing number of farmers worldwide, including Europe.

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Modifications in vegetation cover can have an impact on the climate through changes in biogeochemical and biogeophysical processes. In this paper, the tree canopy cover percentage of a savannah-like ecosystem (montado/dehesa) was estimated at Landsat pixel level for 2011, and the role of different canopy cover percentages on land surface albedo (LSA) and land surface temperature (LST) were analysed. A modelling procedure using a SGB machine-learning algorithm and Landsat 5-TM spectral bands and derived vegetation indices as explanatory variables, showed that the estimation of montado canopy cover was obtained with good agreement (R2 = 78.4%). Overall, montado canopy cover estimations showed that low canopy cover class (MT_1) is the most representative with 50.63% of total montado area. MODIS LSA and LST products were used to investigate the magnitude of differences in mean annual LSA and LST values between contrasting montado canopy cover percentages. As a result, it was found a significant statistical relationship between montado canopy cover percentage and mean annual surface albedo (R2 = 0.866, p < 0.001) and surface temperature (R2 = 0.942, p < 0.001). The comparisons between the four contrasting montado canopy cover classes showed marked differences in LSA (χ2 = 192.17, df = 3, p < 0.001) and LST (χ2 = 318.18, df = 3, p < 0.001). The highest montado canopy cover percentage (MT_4) generally had lower albedo than lowest canopy cover class, presenting a difference of −11.2% in mean annual albedo values. It was also showed that MT_4 and MT_3 are the cooler canopy cover classes, and MT_2 and MT_1 the warmer, where MT_1 class had a difference of 3.42 °C compared with MT_4 class. Overall, this research highlighted the role that potential changes in montado canopy cover may play in local land surface albedo and temperature variations, as an increase in these two biogeophysical parameters may potentially bring about, in the long term, local/regional climatic changes moving towards greater aridity.

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We propose an alternative crack propagation algo- rithm which effectively circumvents the variable transfer procedure adopted with classical mesh adaptation algo- rithms. The present alternative consists of two stages: a mesh-creation stage where a local damage model is employed with the objective of defining a crack-conforming mesh and a subsequent analysis stage with a localization limiter in the form of a modified screened Poisson equation which is exempt of crack path calculations. In the second stage, the crack naturally occurs within the refined region. A staggered scheme for standard equilibrium and screened Poisson equa- tions is used in this second stage. Element subdivision is based on edge split operations using a constitutive quantity (damage). To assess the robustness and accuracy of this algo- rithm, we use five quasi-brittle benchmarks, all successfully solved.