955 resultados para Forest management -- Catalonia


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This study investigated the influence of harvest residue management practices on soil organic matter (SOM) composition and quality from two second-rotation Eucalyptus globulus plantations in southwestern Australia, using solid-state 13C nuclear magnetic resonance (NMR) spectroscopy with cross-polarisation and magic-angle-spinning (CPMAS). Soil samples (0–5 cm) were collected every 12 months for 5 years from two sites that had contrasting soil types and fertility. Harvest residue management treatments established at both sites were (a) no harvest residues; and (b) double harvest residues. The use of 13C CPMAS and DD NMR spectroscopy enabled the successful non-destructive detection of SOM quality changes in the two E. globulus plantations. Relative intensities of 13C CPMAS NMR spectral regions were similar at both sites, and for both harvest residue treatments, indicating that SOM composition was also similar. Dipolar dephasing (DD) NMR spectra revealed resonances in SOM assigned to lignin and tannin structures, with larger resonances in the carbonyl and alkyl C regions that were indicative of cuticular material, enabling detection of changes in SOM quality. Retention of double harvest residues on the soil surface increased the soil quality compared with removal of all harvest residues at both sites as indicated by the NMR aromaticities, but this was most noticeable at Manjimup, which had greater initial soil fertility.

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Disaster management is one of the most relevant application fields of wireless sensor networks. In this application, the role of the sensor network usually consists of obtaining a representation or a model of a physical phenomenon spreading through the affected area. In this work we focus on forest firefighting operations, proposing three fully distributed ways for approximating the actual shape of the fire. In the simplest approach, a circular burnt area is assumed around each node that has detected the fire and the union of these circles gives the overall fire’s shape. However, as this approach makes an intensive use of the wireless sensor network resources, we have proposed to incorporate two in-network aggregation techniques, which do not require considering the complete set of fire detections. The first technique models the fire by means of a complex shape composed of multiple convex hulls representing different burning areas, while the second technique uses a set of arbitrary polygons. Performance evaluation of realistic fire models on computer simulations reveals that the method based on arbitrary polygons obtains an improvement of 20% in terms of accuracy of the fire shape approximation, reducing the overhead in-network resources to 10% in the best case.

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Climate change is emerging as one of the major threats to natural communities of the world’s ecosystems; and biodiversity hotspots, such as Madeira Island, might face a challenging future in the conservation of endangered land snails’ species. With this thesis, progresses have been made in order to properly understand the impact of climate on these vulnerable taxa; and species distribution models coupled with GIS and climate change scenarios have become crucial to understand the relations between species distribution and environmental conditions, identifying threats and determining biodiversity vulnerability. With the use of MaxEnt, important changes in the species suitable areas were obtained. Laurel forest species, highly dependent on precipitation and relative humidity, may face major losses on their future suitable areas, leading to the possible extinction of several endangered species, such as Leiostyla heterodon. Despite the complexity of the biological systems, the intrinsic uncertainty of species distribution models and the lack of information about land snails’ functional traits, this analysis contributed to a pioneer study on the impacts of climate change on endemic species of Madeira Island. The future inclusion of predictions of the effect of climate change on species distribution as part of IUCN assessments could contribute to species prioritizing, promoting specific management actions and maximizing conservation investment.

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This paper deals with growth rates of trees > 5cm dbh over an eight-year period from 257 species at the Tapajós National Forest. The discussion is centred on the behaviour of the forest after logging. Permanent sample plots were established in 1981 and measured at the first time. The area was logged in 1982. Measurements after logging occurred in 1983, 1987 and 1989. Considering all species together, diameter increment was similar for both intensities of logging until five years after logging. Light-demanding species showed significantly higher growth rates than shade-tolerant species in the logged forest, with greater increment in the heavier treatment intensity. Commercial species also had higher growth rates in the heavier logged area, although those were significantly different only in the period from one to five years after logging. In the undisturbed forest, growth rates increased with increasing dbh size. At species level, growth rate varied between and within treatments, as well as between trees within species, depending mainly on degree of canopy opening. The logging favoured the growth of commercial species, chiefly the light-demanders. Therefore, if the same growth conditions continue being given, for example by silvicultural treatments, to those species of commercial interest, the forest would reach a stock available for harvesting around year 30 after logging. However, the high variation in increment rates indicates that an eight-year period is not sufficient to allow predictions on cutting cycles or polycyclic management systems for the study forest.

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Construction of hydroelectric dams in tropical regions has been contributing significantly to forest fragmentation. Alterations at edges of forest fragments impact plant communities that suffer increases in tree damage and dead, and decreases in seedling recruitment. This study aimed to test the core-area model in a fragmented landscape caused by construction of a hydroelectric power plant in the Brazilian Amazon. We studied variations in forest structure between the margin and interiors of 17 islands of 8-100 hectares in the Tucuruí dam reservoir, in two plots (30 and >100m from the margin) per island. Mean tree density, basal area, seedling density and forest cover did not significantly differ between marginal and interior island plots. Also, no significant differences were found in liana density, dead tree or damage for margin and interior plots. The peculiar topographic conditions associated with the matrix habitat and shapes of the island seem to extend edge effects to the islands' centers independently of the island size, giving the interior similar physical microclimatic conditions as at the edges. We propose a protocol for assessing the ecological impacts of edge effects in fragments of natural habitat surrounded by induced (artificial) edges. The protocol involves three steps: (1) identification of focal taxa of particular conservation or management interest, (2) measurement of an "edge function" that describes the response of these taxa to induced edges, and (3) use of a "Core-Area Model" to extrapolate edge function parameters to existing or novel situations.

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ABSTRACT Using camera traps and capture/recapture analyses we recorded the presence and abundance of cat species at Turvo State Park, in southern Brazil. Ocelot [Leopardus pardalis (Linnaeus, 1758)] population density was estimated for two areas of the park, with differing management profiles. Density estimates varied from 0.14 to 0.26 indiv. km2. Another five cat species were recorded at very low frequencies, precluding more accurate analyses. We estimate 24 to 45 ocelots occur in the reserve, which is probably too small for long-term maintenance of the population, if isolated. However, if habitat integrity and connectivity between the Park and the Green Corridor of Misiones is maintained, an estimated ocelot population of 1,680 individuals should have long-term viability.

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The sensitivity of altitudinal and latitudinal tree-line ecotones to climate change, particularly that of temperature, has received much attention. To improve our understanding of the factors affecting tree-line position, we used the spatially explicit dynamic forest model TreeMig. Although well-suited because of its landscape dynamics functions, TreeMig features a parabolic temperature growth response curve, which has recently been questioned. and the species parameters are not specifically calibrated for cold temperatures. Our main goals were to improve the theoretical basis of the temperature growth response curve in the model and develop a method for deriving that curve's parameters from tree-ring data. We replaced the parabola with an asymptotic curve, calibrated for the main species at the subalpine (Swiss Alps: Pinus cembra, Larix decidua, Picea abies) and boreal (Fennoscandia: Pinus sylvestris, Betula pubescens, P. abies) tree-lines. After fitting new parameters, the growth curve matched observed tree-ring widths better. For the subalpine species, the minimum degree-day sum allowing, growth (kDDMin) was lowered by around 100 degree-days; in the case of Larix, the maximum potential ring-width was increased to 5.19 mm. At the boreal tree-line, the kDDMin for P. sylvestris was lowered by 210 degree-days and its maximum ring-width increased to 2.943 mm; for Betula (new in the model) kDDMin was set to 325 degree-days and the maximum ring-width to 2.51 mm; the values from the only boreal sample site for Picea were similar to the subalpine ones, so the same parameters were used. However, adjusting the growth response alone did not improve the model's output concerning species' distributions and their relative importance at tree-line. Minimum winter temperature (MinWiT, mean of the coldest winter month), which controls seedling establishment in TreeMig, proved more important for determining distribution. Picea, P. sylvestris and Betula did not previously have minimum winter temperature limits, so these values were set to the 95th percentile of each species' coldest MinWiT site (respectively -7, -11, -13). In a case study for the Alps, the original and newly calibrated versions of TreeMig were compared with biomass data from the National Forest Inventor), (NFI). Both models gave similar, reasonably realistic results. In conclusion, this method of deriving temperature responses from tree-rings works well. However, regeneration and its underlying factors seem more important for controlling species' distributions than previously thought. More research on regeneration ecology, especially at the upper limit of forests. is needed to improve predictions of tree-line responses to climate change further.

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Water scarcity is a long-standing problem in Catalonia, as there are significant differences in the spatial and temporal distribution of water through the territory. There has consequently been a debate for many years about whether the solution to water scarcity must be considered in terms of efficiency or equity, the role that the public sector must play and the role that market-based instruments should play in water management. The aim of this paper is to use a Computable General Equilibrium (CGE) model to analyze the advantages and disadvantages associated with different policy instruments, from both a supply and a demand viewpoint, which can be applied to water management in Catalonia. We also introduce an ecological sector in our CGE model, allowing us to analyze the environmental impact of the alternative policies simulated. The calibration of the exogenous variables of the CGE model is performed by using a Social Accounting Matrix (SAM) for the Catalan economy with 2001 data. The results suggest that taking into account the principle of sustainability of the resource, the policy debate between supply and demand in water policies is obsolete, and a new combination of policies is required to respect the different values associated with water. Keywords: Water Policies; Computable General Equilibrium Model; Economic Effects; Environmental Effects.

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To start off, this document describes the Catalan model for emergencies response and its reference frame in terms of geography, location population…In addition, describes the main actors involved in emergencies response such as: police, the Fire and Rescue Emergency Service, the Emergency Medical System, Civil Protection, Reception and Management of Emergency Calls, Rural Agents, ADF’s and UME. Civil Protection, Firefighters and Police are includes in the training model developed by the Institute for Public Safety of Catalonia which at the same time does research in both security and safety matters. Research activities are performed by the Area for Research, Knowledge and International Cooperation at the ISPC and an example of these activities are European Research Projects such as COIM-Best (Coordination Improvement by Best Practices) and BESECU (cross-cultural differences of human behaviour in fire disasters and other crisis situations) among others.

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This article examines the governance structures for managing the location and operation of Intensive Livestock Farming Operations (ILFOs). The article focuses on the hog sector and compares two very different jurisdictions: the Province of Manitoba, Canada and the Autonomous Community of Catalonia, Spain. Both are regions that have witnessed recent increases in hog production, including increasing spatial concentration of ILFOs and increasing size of those ILFOs. Policy has both fostered and sought to manage the increased production. Following a brief background description of restructuring, the changing legislative framework for Manitoba and Catalonia are described. Keywords: environmental regulations, hog farms, manure management, animal feeding operations. JEL: Q15, Q58, R52, O57

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A través dels seus serveis de gestió documental a les aules de la Universitat Oberta de Catalunya (Universitat Oberta de Catalunya, UOC), la Biblioteca de la UOC actua com un veritable facilitador de l'aprenentatge i l'ensenyament i té un paper central en el model de aprenentatge de la universitat. A més a més, serveix com un model a seguir per altres biblioteques universitàries en termes del que s'espera d'elles en el marc del nou Espai Europeu d'Educació Superior (EEES) i la creixent necessitat que funcionin com a centres de recursos d'aprenentatge. Contribuint a l'èxit de la biblioteca, el model d'aprenentatge i ensenyament de la UOC crea un entorn d'aprenentatge virtual i asíncron per als estudiants, i permet a la biblioteca de la UOC ser present en totes les seves aules.

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Resum en anglès del projecte de recerca L'empresa xarxa a Catalunya. TIC, productivitat, competitivitat, salaris i beneficis a l'empresa catalana té com a objectiu principal constatar que la consolidació d'un nou model estratègic, organitzatiu i d'activitat empresarial, vinculat amb la inversió i l'ús de les TIC (o empresa xarxa), modifica substancialment els patrons de comportament dels resultats empresarials, en especial la productivitat, la competitivitat, les retribucions dels treballadors i el benefici. La contrastació empírica de les hipòtesis de treball l'hem feta per mitjà de les dades d'una enquesta a una mostra representativa de 2.038 empreses catalanes. Amb la perspectiva de l'impacte de la inversió i l'ús de les TIC no s'aprecia una relació directa entre els processos d'innovació digital i els resultats de l'activitat de l'empresa catalana. En aquest sentit, hem hagut de segmentar el teixit productiu català per a buscar les organitzacions en què el procés de coinnovació tecnològica digital i organitzativa és més present i en què la intensitat de l'ús del coneixement és un recurs molt freqüent per a poder copsar impactes rellevants en els principals resultats empresarials. Això és així perquè l'economia catalana, avui, presenta una estructura productiva dual.

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El projecte se centra en el la vall d’Alinyà, en els terrenys de la Fundació Territori i Paisatge que abasten des dels cims del Port del Comte, a més de 2.000 m d’altitud fins més avall del nucli de Perles en els 500 m, en un ambient de muntanya a la comarca de l’Alt Urgell, Catalunya. L’objectiu principal ha estat diagnosticar la situació de la ramaderia extensiva de la vall, tot predient la seva viabilitat socioeconòmica com a estratègia de futur, tant pel que fa la seva població, com per les característiques d’un paisatge en mosaic molt ben afaiçonat per la mà humana en el passat. Aquesta diversitat paisatgística assegurada per l’existència de la ramaderia extensiva, provoca una riquesa en biodiversitat ecològica, en front del creixement continu de la massa forestal causat per l’abandonament de les activitats a la muntanya. Un dels aspectes estudiats de la ramaderia de la vall, ha estat la gestió dels cinc ramats existents en l’actualitat, dos de vaques, un de cabres, un d’ovelles i un de cavalls. Des de la identificació dels moviments de transtermitància durant les diferents estacions de l’any, a la de l’obtenció dels diferents recursos alimentaris pel bestiar provinents directament de la natura. Les entrevistes personals als ramaders han estat una important font d’informació i de tractament de dades per poder diagnosticar la situació actual del sector i de la figura del pastor com a figura professional clau en la vessant socioeconòmica i paisatgística local. Es van poder identificar clarament els problemes amb els quals es troba la ramaderia extensiva i quins reptes presenta per poder arribar a ser un sector de futur per a la població de la vall. En aquest context es proposen mesures de millora de l’activitat i de difusió dels productes agroramaders de qualitat.

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The populations of Capercaillie (Tetrao urogallus), the largest European grouse, have seriously declined during the last century over most of their distribution in western and central Europe. In the Jura mountains, the relict population is now isolated and critically endangered (about 500 breeding adults). We developed a simulation software (TetrasPool) that accounts for age and spatial structure as well as stochastic processes, to perform a viability analysis and explore management scenarios for this population, capitalizing on a 24 years-long series of field data. Simulations predict a marked decline and a significant extinction risk over the next century, largely due to environmental and demographic stochasticity (average values of life-history parameters would otherwise allow stability). Variances among scenarios mainly stem from uncertainties about the shape and intensity of density dependence. Uncertainty analyses suggest to focus conservation efforts on enhancing, not only adult survival (as often advocated for long-lived species), but also recruitment. The juvenile stage matters when local populations undergo extinctions, because it ensures connectivity and recolonization. Besides limiting human perturbations, a silvicultural strategy aimed at opening forest structure should improve the quality and surface of available patches, independent of their size and localization. Such measures are to be taken urgently, if the population is to be saved.

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The organisation of inpatient care provision has undergone significant reform in many southern European countries. Overall across Europe, public management is moving towards the introduction of more flexibility and autonomy . In this setting, the promotion of the further decentralisation of health care provision stands out as a key salient policy option in all countries that have hitherto had a traditionally centralised structure. Yet, the success of the underlying incentives that decentralised structures create relies on the institutional design at the organisational level, especially in respect of achieving efficiency and promoting policy innovation without harming the essential principle of equal access for equal need that grounds National Health Systems (NHS). This paper explores some of the specific organisational developments of decentralisation structures drawing from the Spanish experience, and particularly those in the Catalonia. This experience provides some evidence of the extent to which organisation decentralisation structures that expand levels of autonomy and flexibility lead to organisational innovation while promoting activity and efficiency. In addition to this pure managerial decentralisation process, Spain is of particular interest as a result of the specific regional NHS decentralisation that started in the early 1980 s and was completed in 2002 when all seventeen autonomous communities that make up the country had responsibility for health care services.Already there is some evidence to suggest that this process of decentralisation has been accompanied by a degree of policy innovation and informal regional cooperation. Indeed, the Spanish experience is relevant because both institutional changes took place, namely managerial decentralisation leading to higher flexibility and autonomy- alongside an increasing political decentralisation at the regional level. The coincidence of both processes could potentially explain why some organisation and policy innovation resulting from policy experimentation at the regional level might be an additional featureto take into account when examining the benefits of decentralisation.