966 resultados para forest sector models
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The present paper develops and tests a model explaining public sector derivative use in terms of budget discrepancy minimization. The model is different from private sector models. Private sector models do not readily translate into the public sector, which typically faces different objectives. Hypotheses are developed and tested using logistic regression over a sample of Australian Commonwealth public sector organizations. It is found that public sector organization derivative use is positively correlated with liabilities and size consistent with the hypotheses concerning budget discrepancy management.
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Cette thèse est une contribution à la modélisation, la planification et l’optimisation du transport pour l’approvisionnement en bois de forêt des industries de première transformation. Dans ce domaine, les aléas climatiques (mise au sol des bois par les tempêtes), sanitaires (attaques bactériologiques et fongiques des bois) et commerciaux (variabilité et exigence croissante des marchés) poussent les divers acteurs du secteur (entrepreneurs et exploitants forestiers, transporteurs) à revoir l’organisation de la filière logistique d’approvisionnement, afin d’améliorer la qualité de service (adéquation offre-demande) et de diminuer les coûts. L’objectif principal de cette thèse était de proposer un modèle de pilotage améliorant la performance du transport forestier, en respectant les contraintes et les pratiques du secteur. Les résultats établissent une démarche de planification hiérarchique des activités de transport à deux niveaux de décision, tactique et opérationnel. Au niveau tactique, une optimisation multi-périodes permet de répondre aux commandes en minimisant l’activité globale de transport, sous contrainte de capacité agrégée des moyens de transport accessibles. Ce niveau permet de mettre en œuvre des politiques de lissage de charge et d’organisation de sous-traitance ou de partenariats entre acteurs de transport. Au niveau opérationnel, les plans tactiques alloués à chaque transporteur sont désagrégés, pour permettre une optimisation des tournées des flottes, sous contrainte des capacités physiques de ces flottes. Les modèles d’optimisation de chaque niveau sont formalisés en programmation linéaire mixte avec variables binaires. L’applicabilité des modèles a été testée en utilisant un jeu de données industrielles en région Aquitaine et a montré des améliorations significatives d’exploitation des capacités de transport par rapport aux pratiques actuelles. Les modèles de décision ont été conçus pour s’adapter à tout contexte organisationnel, partenarial ou non : la production du plan tactique possède un caractère générique sans présomption de l’organisation, celle-ci étant prise en compte, dans un deuxième temps, au niveau de l’optimisation opérationnelle du plan de transport de chaque acteur.
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The application of airborne laser scanning (ALS) technologies in forest inventories has shown great potential to improve the efficiency of forest planning activities. Precise estimates, fast assessment and relatively low complexity can explain the good results in terms of efficiency. The evolution of GPS and inertial measurement technologies, as well as the observed lower assessment costs when these technologies are applied to large scale studies, can explain the increasing dissemination of ALS technologies. The observed good quality of results can be expressed by estimates of volumes and basal area with estimated error below the level of 8.4%, depending on the size of sampled area, the quantity of laser pulses per square meter and the number of control plots. This paper analyzes the potential of an ALS assessment to produce certain forest inventory statistics in plantations of cloned Eucalyptus spp with precision equal of superior to conventional methods. The statistics of interest in this case were: volume, basal area, mean height and dominant trees mean height. The ALS flight for data assessment covered two strips of approximately 2 by 20 Km, in which clouds of points were sampled in circular plots with a radius of 13 m. Plots were sampled in different parts of the strips to cover different stand ages. The clouds of points generated by the ALS assessment: overall height mean, standard error, five percentiles (height under which we can find 10%, 30%, 50%,70% and 90% of the ALS points above ground level in the cloud), and density of points above ground level in each percentile were calculated. The ALS statistics were used in regression models to estimate mean diameter, mean height, mean height of dominant trees, basal area and volume. Conventional forest inventory sample plots provided real data. For volume, an exploratory assessment involving different combinations of ALS statistics allowed for the definition of the most promising relationships and fitting tests based on well known forest biometric models. The models based on ALS statistics that produced the best results involved: the 30% percentile to estimate mean diameter (R(2)=0,88 and MQE%=0,0004); the 10% and 90% percentiles to estimate mean height (R(2)=0,94 and MQE%=0,0003); the 90% percentile to estimate dominant height (R(2)=0,96 and MQE%=0,0003); the 10% percentile and mean height of ALS points to estimate basal area (R(2)=0,92 and MQE%=0,0016); and, to estimate volume, age and the 30% and 90% percentiles (R(2)=0,95 MQE%=0,002). Among the tested forest biometric models, the best fits were provided by the modified Schumacher using age and the 90% percentile, modified Clutter using age, mean height of ALS points and the 70% percentile, and modified Buckman using age, mean height of ALS points and the 10% percentile.
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O objetivo deste estudo ?? o de estabelecer uma an??lise cr??tica do discurso contempor??neo em gest??o de pessoas, verificando como discurso e pr??tica gerencialistas se reproduzem no setor p??blico, sem que haja a devida an??lise do fator ideol??gico que permeia a gest??o privada. No contexto da idealiza????o de modelos gerenciais, gestores p??blicos s??o ??vidos em implementar modelos do setor privado, que t??m uma l??gica diferente da gest??o do setor p??blico. O artigo estabelece, dessa forma, a an??lise cr??tica desse processo, definindo elementos que possam inspirar a gest??o de organiza????es p??blicas e respeitar as suas especificidades.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Forestry in general and logging in particular continue to be among the three most hazardous sectors in European countries. The aim of this article is to characterize health and safety problems and solutions in E.U. forestry operations, and particularly in Portuguese operations. Forest types, production, employment and ownership are used to characterize the forest sector. Forestry accidents and health problems data are mentioned. Typical hazards associated to the nature of logging operations are systematized. Preventive measures, focused on a wide spectrum of measures, making safety considerations an integral feature of all operational activities from planning to organization to execution and supervision of work are emphasized in this article.
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Summary Ecotones are sensitive to change because they contain high numbers of species living at the margin of their environmental tolerance. This is equally true of tree-lines, which are determined by attitudinal or latitudinal temperature gradients. In the current context of climate change, they are expected to undergo modifications in position, tree biomass and possibly species composition. Attitudinal and latitudinal tree-lines differ mainly in the steepness of the underlying temperature gradient: distances are larger at latitudinal tree-lines, which could have an impact on the ability of tree species to migrate in response to climate change. Aside from temperature, tree-lines are also affected on a more local level by pressure from human activities. These are also changing as a consequence of modifications in our societies and may interact with the effects of climate change. Forest dynamics models are often used for climate change simulations because of their mechanistic processes. The spatially-explicit model TreeMig was used as a base to develop a model specifically tuned for the northern European and Alpine tree-line ecotones. For the latter, a module for land-use change processes was also added. The temperature response parameters for the species in the model were first calibrated by means of tree-ring data from various species and sites at both tree-lines. This improved the growth response function in the model, but also lead to the conclusion that regeneration is probably more important than growth for controlling tree-line position and species' distributions. The second step was to implement the module for abandonment of agricultural land in the Alps, based on an existing spatial statistical model. The sensitivity of its most important variables was tested and the model's performance compared to other modelling approaches. The probability that agricultural land would be abandoned was strongly influenced by the distance from the nearest forest and the slope, bath of which are proxies for cultivation costs. When applied to a case study area, the resulting model, named TreeMig-LAb, gave the most realistic results. These were consistent with observed consequences of land-abandonment such as the expansion of the existing forest and closing up of gaps. This new model was then applied in two case study areas, one in the Swiss Alps and one in Finnish Lapland, under a variety of climate change scenarios. These were based on forecasts of temperature change over the next century by the IPCC and the HadCM3 climate model (ΔT: +1.3, +3.5 and +5.6 °C) and included a post-change stabilisation period of 300 years. The results showed radical disruptions at both tree-lines. With the most conservative climate change scenario, species' distributions simply shifted, but it took several centuries reach a new equilibrium. With the more extreme scenarios, some species disappeared from our study areas (e.g. Pinus cembra in the Alps) or dwindled to very low numbers, as they ran out of land into which they could migrate. The most striking result was the lag in the response of most species, independently from the climate change scenario or tree-line type considered. Finally, a statistical model of the effect of reindeer (Rangifer tarandus) browsing on the growth of Pinus sylvestris was developed, as a first step towards implementing human impacts at the boreal tree-line. The expected effect was an indirect one, as reindeer deplete the ground lichen cover, thought to protect the trees against adverse climate conditions. The model showed a small but significant effect of browsing, but as the link with the underlying climate variables was unclear and the model was not spatial, it was not usable as such. Developing the TreeMig-LAb model allowed to: a) establish a method for deriving species' parameters for the growth equation from tree-rings, b) highlight the importance of regeneration in determining tree-line position and species' distributions and c) improve the integration of social sciences into landscape modelling. Applying the model at the Alpine and northern European tree-lines under different climate change scenarios showed that with most forecasted levels of temperature increase, tree-lines would suffer major disruptions, with shifts in distributions and potential extinction of some tree-line species. However, these responses showed strong lags, so these effects would not become apparent before decades and could take centuries to stabilise. Résumé Les écotones son sensibles au changement en raison du nombre élevé d'espèces qui y vivent à la limite de leur tolérance environnementale. Ceci s'applique également aux limites des arbres définies par les gradients de température altitudinaux et latitudinaux. Dans le contexte actuel de changement climatique, on s'attend à ce qu'elles subissent des modifications de leur position, de la biomasse des arbres et éventuellement des essences qui les composent. Les limites altitudinales et latitudinales diffèrent essentiellement au niveau de la pente des gradients de température qui les sous-tendent les distance sont plus grandes pour les limites latitudinales, ce qui pourrait avoir un impact sur la capacité des espèces à migrer en réponse au changement climatique. En sus de la température, la limite des arbres est aussi influencée à un niveau plus local par les pressions dues aux activités humaines. Celles-ci sont aussi en mutation suite aux changements dans nos sociétés et peuvent interagir avec les effets du changement climatique. Les modèles de dynamique forestière sont souvent utilisés pour simuler les effets du changement climatique, car ils sont basés sur la modélisation de processus. Le modèle spatialement explicite TreeMig a été utilisé comme base pour développer un modèle spécialement adapté pour la limite des arbres en Europe du Nord et dans les Alpes. Pour cette dernière, un module servant à simuler des changements d'utilisation du sol a également été ajouté. Tout d'abord, les paramètres de la courbe de réponse à la température pour les espèces inclues dans le modèle ont été calibrées au moyen de données dendrochronologiques pour diverses espèces et divers sites des deux écotones. Ceci a permis d'améliorer la courbe de croissance du modèle, mais a également permis de conclure que la régénération est probablement plus déterminante que la croissance en ce qui concerne la position de la limite des arbres et la distribution des espèces. La seconde étape consistait à implémenter le module d'abandon du terrain agricole dans les Alpes, basé sur un modèle statistique spatial existant. La sensibilité des variables les plus importantes du modèle a été testée et la performance de ce dernier comparée à d'autres approches de modélisation. La probabilité qu'un terrain soit abandonné était fortement influencée par la distance à la forêt la plus proche et par la pente, qui sont tous deux des substituts pour les coûts liés à la mise en culture. Lors de l'application en situation réelle, le nouveau modèle, baptisé TreeMig-LAb, a donné les résultats les plus réalistes. Ceux-ci étaient comparables aux conséquences déjà observées de l'abandon de terrains agricoles, telles que l'expansion des forêts existantes et la fermeture des clairières. Ce nouveau modèle a ensuite été mis en application dans deux zones d'étude, l'une dans les Alpes suisses et l'autre en Laponie finlandaise, avec divers scénarios de changement climatique. Ces derniers étaient basés sur les prévisions de changement de température pour le siècle prochain établies par l'IPCC et le modèle climatique HadCM3 (ΔT: +1.3, +3.5 et +5.6 °C) et comprenaient une période de stabilisation post-changement climatique de 300 ans. Les résultats ont montré des perturbations majeures dans les deux types de limites de arbres. Avec le scénario de changement climatique le moins extrême, les distributions respectives des espèces ont subi un simple glissement, mais il a fallu plusieurs siècles pour qu'elles atteignent un nouvel équilibre. Avec les autres scénarios, certaines espèces ont disparu de la zone d'étude (p. ex. Pinus cembra dans les Alpes) ou ont vu leur population diminuer parce qu'il n'y avait plus assez de terrains disponibles dans lesquels elles puissent migrer. Le résultat le plus frappant a été le temps de latence dans la réponse de la plupart des espèces, indépendamment du scénario de changement climatique utilisé ou du type de limite des arbres. Finalement, un modèle statistique de l'effet de l'abroutissement par les rennes (Rangifer tarandus) sur la croissance de Pinus sylvestris a été développé, comme première étape en vue de l'implémentation des impacts humains sur la limite boréale des arbres. L'effet attendu était indirect, puisque les rennes réduisent la couverture de lichen sur le sol, dont on attend un effet protecteur contre les rigueurs climatiques. Le modèle a mis en évidence un effet modeste mais significatif, mais étant donné que le lien avec les variables climatiques sous jacentes était peu clair et que le modèle n'était pas appliqué dans l'espace, il n'était pas utilisable tel quel. Le développement du modèle TreeMig-LAb a permis : a) d'établir une méthode pour déduire les paramètres spécifiques de l'équation de croissance ä partir de données dendrochronologiques, b) de mettre en évidence l'importance de la régénération dans la position de la limite des arbres et la distribution des espèces et c) d'améliorer l'intégration des sciences sociales dans les modèles de paysage. L'application du modèle aux limites alpines et nord-européennes des arbres sous différents scénarios de changement climatique a montré qu'avec la plupart des niveaux d'augmentation de température prévus, la limite des arbres subirait des perturbations majeures, avec des glissements d'aires de répartition et l'extinction potentielle de certaines espèces. Cependant, ces réponses ont montré des temps de latence importants, si bien que ces effets ne seraient pas visibles avant des décennies et pourraient mettre plusieurs siècles à se stabiliser.
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Tämä teksti on työselostus indeksin ekologinen jalanjälki metsäosion laskennan menetelmiä selvittävästä tutkimuksesta. Tutkimusraportti alkaa selostuksella, jossa kerrotaanaiheen taustaa ja yhteys, missä liikutaan: indikaattorien hyödyntäminen, politiikka kestävän kehityksen ympärillä sekä hieman kestävän kehityksen kokonaisuudesta. Tämä on johdanto varsinaiseen tutkimuksen sisältöön. Tekstissä raportoidaan ekologisen jalanjäljen vuoden 2001 laskentataulukon mukainen metsäosion laskentamenetelmä sekä myös hiilidioksidin sitoutumisen jalanjäljen ja biokapasiteetin laskentamenetelmät. Tutkimuksen tuloksia ovat laskennasta löytyneet epäkohdat ja niiden kehittäminen. Tekstissä koetetaan myös selventää ekologisen jalanjäljen kokonaisuutta ja sitä miten sen tuloksia tulisi lukea.
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Tuontipuulla onsuuri merkitys suomalaiselle metsäteollisuudelle. Tämän tutkimuksen tavoitteitaovat Suomen metsäteollisuuden puuntuonnin tärkeimmän alueen, Luoteis-Venäjän metsävarojen kartoittaminen ja niiden hyödyntämismahdollisuuksien arviointi. Työssä käsitellään myös lyhyesti suoria ulkomaisia investointeja Luoteis-Venäjän metsäsektorille. Luoteis-Venäjällä on suuremmat metsävarat kuin muulla Euroopalla yhteensä. Koko maailmassa on vain 5 valtiota, jolla olisi suuremmat metsävarat kuin sillä. Eniten metsiä Luoteis-Venäjällä on Komin tasavallassa ja Arkangelin alueella. Kuusi ja mänty ovat yleisimmät puulajit. Hyvien iikenneyhteyksien varsilta metsät on hakattu ja jätetty uudistamatta, minkä seurauksena koivu ja haapa ovat vallanneet alaa havupuilta. Niinpä alueen metsäteollisuus, etenkin sahateollisuus kärsii puupulasta. Suomen metsäteollisuus on sen sijaan hyötynyt siitä, että koivukuitupuuta on runsaasti saatavilla. Metsävarojen hyödyntämisen suurimmatesteet ovat harva ja huonokuntoinen metsätieverkosto sekä metsien riittämätön hoito. Venäläisestä näkökulmasta alueen metsävarat ovat vajaakäytössä: vuotuiset hakkuut ovat alle puolet kasvusta, suuri osa puusta viedään raakapuuna ulkomaille, ja alueen metsäteollisuuden tuotteiden jalostusarvo jää alhaiseksi. Suoria ulkomaisia investointeja Luoteis-Venäjän metsäsektorille houkuttelevat suuret puuvarat, halpa energia ja tulevaisuudessa etenkin kasvavat markkinat. Investointejahaittaavat huono infrastruktuuri, korruptio ja epävarmuus maan kehityksestä.
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Suomen metsäteollisuuden käyttämästä puusta neljännes on tuontipuuta, josta Venäjän tuonnin osuus on hyvin merkittävä. Suomen metsäteollisuus on riippuvainen etenkin Luoteis-Venäjän metsien puusta. Venäjä pyrkii nostamaan metsäteollisuuden jalostusastetta ja hyödyntämään voimallisemmin omia metsävaroja, mikä merkitsee suuria haasteita suomalaiselle metsäteollisuudelle ja sen raaka-ainehuollolle. Tässä raportissa tarkastellaan Luoteis-Venäjän metsävaroja, metsänkäyttöä ja sen ongelmia sekä metsien hallinnointia. Lisäksi käsitellään Luoteis-Venäjän metsäsektoria ja siihen tehtyjä suoria ulkomaisia investointeja. Lopuksi kuvataan Luoteis-Venäjän kuljetusinfrastruktuuria sekä arvioidaan Luoteis-Venäjän metsävarojen käytön potentiaalia.
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La repoblación forestal es una de las alternativas técnicas más importantes en la restauración ecológica. La selección correcta de las especies es una de las decisiones más importantes del proyecto, por las implicaciones significativas que a largo plazo tiene en los costes de gestión y en el valor de la comunidad final. Se analizan los factores y las etapas del proceso de selección así como los conceptos teóricos que han servido de base a los modelos de restauración forestal. En este artículo presentamos algunas de las contribuciones que el Profesor Ruiz de la Torre ha realizado en relación al conocimiento de las características ecológicas y selvícolas de las principales especies arbóreas españolas, así como de los mecanismos de sucesión de la vegetación.
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The main purposes of this study are analyzing of forest sector of North-West and research of potentials of wood fuel market in this region. Research is focused on definition of the most perspective areas for export of wood fuel: logging residues, industrial wood processing residues, pellets and briquettes. Russian wood energy industry is very young in comparison with European countries. Nowadays there are no support and serious attention from the government to this sector. Hence almost all wood fuel market is oriented to the Western Europe. Export of wood fuel is dominated over the internal consumption. Pellet production in North –West is rapidly growing. Despite internal market has been developed the lion's share of pellets goes to export. Part of industrial wood processing residues is used by producers for their own goals, part goes to the export and rest of them is not used at all. Logging residues as raw materials for fuel have great potentials; most of them are left in a forest. Special techniques for their processing are too expensive for Russian entrepreneur. Some parts of North –West, which are situated close to the border with European countries, are potential for export. Political, economical and logistical challenges are complicated facilities for foreign customer to purchase wood fuel in remote parts of North-West. However some decisions for solving this problem exist and Russian manufactures are still interested in export of their products.
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Sustainability is the aim of forest management and forest regulation in many countries. Accordingly, forest management has been steered towards more environmentally friendly methods and new regulatory instruments have been introduced. At the same time, wood trade and forest industry have become a global business. Even if the importance of national forest legislation has not decreased, it has been widely acknowledged that national regulation of forest management is no longer sufficient. The movement of goods does not acknowledge boundaries, even though most negative environmental and social consequences stay in the country of origin of wood and other raw materials. As a partial solution to this dilemma, different kinds of regulations have been developed. Various forest certification schemes and wood trade regulation in the EU (995/2010) are examples of efforts to prevent illegal logging and unsustainable forestry. The Finland-based forest industry is to a varying extent dependent on wood trade from Russia. Especially in the 1990‟s, ethical questions concerning import of wood from Russian old growth forests near the Finnish border were widely discussed. Consequently, forest industry enterprises have developed systems to trace the origin of wood and to buy certified wood from Russia. The aim of the research has been to evaluate Finnish and Russian forest regulations in order to investigate what kind of forest management these regulations enhance, and to what extent ecologically sustainable forest management has been integrated into different forms of regulation. I have examined Finnish and Russian forest regulation in four separate articles based on the topics of the Russian Forest Code, forest certification and other voluntary forest protection measures in Russia, Finnish forest certification and Finnish forest legislation. One objective has been to analyse the roles voluntary forest certification plays in promoting sustainable forest management in different countries. In my research, I have mainly concentrated on ecological sustainability and protection of biodiversity, although other aspects of sustainable forest management have been touched upon in different articles. In the following I shall conclude the findings of my research. When the current Russian Forest Code (2006) was being adopted, the main emphasis was not on ecological issues, but on reorganizing forest governance. The role of ecological requirements was even slightly diminished during the legislative reform. There are, nevertheless, still stipulations aiming at ecological sustainability, such as the division of forests into different forest management categories and various protection zones. In 2000, FSC forest certification arrived in Russia, at present covering already 28 million hectares of forests. The PEFC scheme is now in use as well, but to a much lesser extent. If properly implemented, Russian forest certification schemes clearly improve the level of ecological and social sustainability of forestry in Russia. Certification criteria, however, are partly in conflict with the Russian forest legislation and certified enterprises have been forced to pay fines or to negotiate with forest authorities. This clearly indicates that even if Russian forest legislation has otherwise been liberalized to a certain extent, some significant paternalism still exists. Voluntary, hands-on biodiversity protection measures are not valued, and they are not part of the official protection policies as in many other countries. However, there have been some regional solutions to this dilemma. In the Republic of Karelia forest authorities have approved a set of forest biodiversity protection rules created by a local NGO and a forest industry enterprise. By following these local rules, an enterprise can avoid fines for protection measures. The current Finnish Forest Act was adopted in 1996. It brought forest legislation into a new era as some ecological aspects were integrated into forest legislation. The various soft-law forest management recommendations further increased the level of biodiversity protection. My evaluation of the overall legitimacy of the Finnish forest legislation and forest management paradigm revealed, however, several problematic issues. As part of this study I analysed the history of the current forest management paradigm. This analysis revealed the path dependency which still hinders the protection of biodiversity and clearly decreases the general legitimacy of forest management. Due to several historical reasons only even-structured forest management based on clear cuts has for decades been officially approved in Finland. Due to increasing demands of forest owners the legislation is finally being revised. Yet, the official approval of uneven-structured forest management would not be enough to fully improve ecological, social and cultural legitimacy. The latest ecological theories and knowledge of endangered species should be taken into account in the on-going reform of forest legislation as well as the modernisation. Forest legislation is one of the very few spheres of Finnish environmental legislation where openness and participation are still considered a threat. The first Finnish forest certification scheme, PEFC, was established in 2000. It now covers more than 20 million hectares, about 95% of the forests in Finland. PEFC Finland does not require a higher level of biodiversity protection than the recommendations by Tapio (the Development Centre for Forestry), but certification has unified forest management practices and requires more protection measures than mere forest legislation. The study suggests that in Finland PEFC has not functioned as an instrument which would substantially improve the level of forest management. Rather it has supported the status quo of the forest sector. While the ecological and social responsibility of Finland-based forest corporations was one impetus for this research, I want to conclude that there are problems related to forest legislation and non-state regulation in both Finland and Russia. If an enterprise buying wood from Russia buys only certified wood, and carefully avoids wood coming from high conservation value forests that are either ecologically or socially valuable, it can be claimed to be as sustainably produced as in Finland. However, there must be continuous scrutiny of the circumstances. In Russia, the level of the compliance of certification criteria varies considerably, and there are vast unprotected invaluable forest areas. The utilisation of these areas should not be based on short-sighted decisions or lack of consensus among stakeholders.
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Tässä kandidaatintyössä tutkitaan, kuinka vuonna 2008 alkanut maailmanlaajuinen talouskriisi on vaikuttanut suomalaisten metsäteollisuusyhtiöiden kannattavuuteen ja vakavaraisuuteen ja näiden valossa pohtia suomalaisen metsäteollisuuden tulevaisuudennäkymiä, mahdollisuuksia ja uhkia.
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In this paper, we study the macroeconomic implications of sectoral heterogeneity and, in particular, heterogeneity in price setting, through the lens of a highly disaggregated multi-sector model. The model incorporates several realistic features and is estimated using a mix of aggregate and sectoral U.S. data. The frequencies of price changes implied by our estimates are remarkably consistent with those reported in micro-based studies, especially for non-sale prices. The model is used to study (i) the contribution of sectoral characteristics to the observed cross sectional heterogeneity in sectoral output and inflation responses to a monetary policy shock, (ii) the implications of sectoral price rigidity for aggregate output and inflation dynamics and for cost pass-through, and (iii) the role of sectoral shocks in explaining sectoral prices and quantities.