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Prozesse und Regulation der N2O- und N2-Freisetzung aus Waldböden / Processes and Regulation of Nitrous Oxide and Dinitrogen Emission from Forest EcosystemsKoch, Anne-Sophie 30 October 2000 (has links)
No description available.
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Molecular Analysis of Centipede PredationEitzinger, Bernhard 19 July 2013 (has links)
No description available.
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Dissipação e mobilidade dos herbicidas glifosato e oxifluorfen em um solo manejado no sistema de cultivo mínimo e florestado com Eucaliptus grandis / Dissipation and mobility of the herbicides glyphosate and oxyfluorfen in soil managed by minimum cultivation and forested with Eucaliptus grandisRicardo Eugenio Cassamassimo 13 March 2006 (has links)
O glifosato e o oxifluorfen têm sido os principais herbicidas para controle de plantas invasoras em plantações florestais. Neste contexto, constituíram em objetivos do presente estudo avaliar as taxas de degradação e de lixiviação de glifosato e oxifluorfen em Latossolo Vermelho-Amarelo Distrófico psamítico, manejados no sistema de cultivo mínimo, florestados com eucalipto. Para tal, foi conduzido um experimento em condições de campo, na Estação Experimental de Ciências Florestais de Itatinga, ESALQ/USP (Itatinga SP), sendo as análises realizadas no Laboratório de Resíduos de Pesticidas e Análises Cromatográficas (LARP/USP). Aplicou-se o glifosato (1440g i.a. ha-1) e oxifluorfen (960g i.a. ha-1) em três repetições na dosagem recomendada (4,0 L./ha-1) para condição de campo. A dissipação dos herbicidas foi avaliada por cromatografia. Foram analisadas amostras de serapilheira, solo e solução do solo. Para a avaliação dos teores de herbicidas na serapilheira e no solo foram realizadas amostragens 3 dias antes da aplicação dos herbicidas na testemunha e, nos demais tratamentos, no dia da aplicação 0, 1, 3, 7, 15, 30, 60 e 93 dias após a aplicação dos herbicidas. Foram amostradas a serapilheira e as seguintes camadas de solo: 0-1, 1-2, 2-4, 4-6, 6-10, 10-15 e 15-30 cm. Para avaliar a lixiviação dos herbicidas, amostras de solução do solo foram coletadas em lisímetros ativado por gravidade (sem tensão) e outro por vácuo (com tensão). O lisímetro ativado por gravidade foi instalado sob a serapilheira, 15, 50 e 100 cm de profundidade e o outro lisímetro foi instalado 15, 50, 100 e 300 cm. Para avaliar a fotodegradação do oxifluorfen foram instaladas parcelas na sombra (sombrite a 80%). A meia-vida do glifosato no solo sem serapilheira foi de 10 dias e no solo sob serapilheira, de 47 dias. Sua lixiviação no solo sob serapilheira foi 36% menor do que no solo sem serapilheira. Devido a este efeito, os riscos de contaminação de solos manejados no sistema de cultivo mínimo são menores. A concentração do glifosato decresceu enquanto a do seu metabólito (AMPA) aumentou durante as duas primeiras semanas após sua aplicação. E tais resíduos foram detectados na solução do solo após 8 dias de sua aplicação, a 15 cm de profundidade. A meia-vida de oxifluorfen no solo sem serapilheira foi de 25 dias e no solo com serapilheira sua meia-vida foi reduzida para 13 dias. O oxifluorfen no solo com serapilheira lixiviou até 5cm e no solo sem serapilheira até 8cm. Em ambas as situações as concentrações foram muito baixas. O teor de oxyfluorfen sob sombra foi sempre maior do que sob pleno sol, comprovando sua fotodegradabilidade. / Glyphosate and oxyfluorfen have been the main herbicides used for the control for the weed control in forest plantations. In this context, to evaluate the degradation and the leaching of glyphosate and oxyfluorfen in red-yellow latosols (oxisol) under minimum cultivation of the soil and planted with eucalyptus were the objectives of the present study. To do so, an experiment was carried out under field conditions in the Experimental Forest Science Station at Itatinga, ESALQ/USP (Itatinga SP). The analyses were performed under laboratory conditions at LARP/USP a laboratory of pesticide residues and chromatographic analyses. Oxyfluorfen was applied (960g a. i. ha-1) in (three repetitions) at the recommended dosage (4.0 L./ha-1) for the field conditions. Glyphosate (1440g a. i. ha-1) and oxyfluorfen (960g a. i. ha-1) were applied in three repetitions at the recommended dosage (4.0 L./ha-1) for the filed condition. The dissipation of the herbicides was evaluated by means of chromatography. Samples of litter, soil and soil solution were analyzed. In order to evaluate the herbicide rates in litter and in soil, samplings were performed three days before the herbicides application in the control and, in the other treatments, at the day of application (0), and at 1, 3, 7, 15, 30, 60, and 93 days after the application. litter and the following soil layer were sampled: 0-1, 1-2, 2-4, 4-6, 6-10, 10-15, and 15-30 cm deep. In order to evaluate the herbicides leaching, samples of soil solution were collected in lisimeters activated by gravity (without tension) and by vacuum (with tension). The lisimeter activated by gravity was installed under the litter at 15, 50, and 100 cm deep; the other was installed at 15, 50, 100, and 300 cm deep. In order to evaluate the photodegradation of oxyfluorfen, the plots were installed under shade (shading net at 80%). The half-life of glyphosate in soil without litter was 10 days and in soil under litter was 47 days. The leaching of glyphosate in soil under litter was 36% smaller than in soil without litter. Because this effect, the risk of contamination of soils that have minimum cultivation are small. The concentration of glyphosate decrease while concentration of your principal metabolite (AMPA) increase during the first two week after application. Glyphosate was found in soil solution 8 days after application up to 15cm deep. The half-life of oxyfluorfen in soil without litter was 25 days and in soil under litter was 13 days. Oxyfluorfen was found at 5 cm deep in soil with litter and at 8 cm deep in soil without litter. In both situations the concentration was very low. Along the experiment, oxyfluorfen under shade was always higher than under sun, this proves the photo-degradation.
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Mapeamento e modelagem edafoclimática da produtividade de plantações de Eucalyptus no sul do estado de São Paulo / Mapping and edaphoclimatic modeling of productivity of Eucalyptus plantations at south of São Paulo StateClayton Alcarde Alvares 18 May 2011 (has links)
O estudo do potencial biológico do ecossistema florestal torna-se essencial quando o objetivo é o seu manejo racional, visando a maximização da produtividade, e evitando-se a exaustão dos recursos do sítio florestal. Na área florestal é comum a aplicação de modelos que projetam o futuro do povoamento, pois desta forma pode-se tomar as decisões apropriadas a cerca do manejo a ser seguido. Dentre outros modelos, o 3-PG foi testado para inúmeras espécies florestais e em diversas condições edafoclimáticas, e tem sido reportado, por unanimidade, como uma poderosa ferramenta para auxiliar o manejo de povoamentos florestais. O objetivo desse estudo foi: calibrar, validar e simular a produtividade de plantações clonais de Eucalyptus com o uso do modelo 3-PG integrado a um sistema de informações geográficas. Foram selecionadas 20 parcelas de inventário que continham o material genético C219H (Eucalyptus grandis x E. urophylla) plantados no mesmo espaçamento de 3 x 3m e de mesma idade, com data de plantio no ano 2000, na região de Capão Bonito, sul do estado de São Paulo. Em cada parcela foram realizadas avaliações edáficas, dendrométricas e nutricionais em três árvores médias. A incorporação das características do relevo apresentou diferença no mapeamento da radiação global, principalmente no inverno, onde os efeitos do relevo foram elevados, apresentando diferenças de até 147%, em relação ao relevo plano. O número de geadas mensais foi determinado pela temperatura média mínima mensal, aprensentando uma relação linear negativa. A maioria das variáveis de solos analisadas aproximou-se da distribuição lognormal de freqüências. Na análise geoestatística, as variáveis relacionadas à fertilidade do solo apresentaram maiores alcances de dependência espacial no horizonte A, indicando que há maior homogeneidade na distribuição dos nutrientes na camada superficial do solo. A CTCefetiva apresentou relação exponencial positiva com o volume de madeira. Paralela a essa curva, foi proposta uma equação relacionando o índice de fertilidade do modelo 3-PGIS e esse atributo do solo. O teor de argila exerceu forte influência sobre os teores de água na capacidade de campo e no ponto de murcha permanente, por conseguinte, na disponibilidade de água dos solos. A máxima biomassa de fuste, encontrada nos povoamentos florestais manejados com elevado padrão tecnológico, relacionou-se diretamente com o teor argila+silte. Essa mesma propriedade do solo, exerceu influência na densidade da madeira. Sítios de maiores produtividades, por conseguinte, de maior teor de argila+silte, resultaram em árvores de menor densidade básica. Os teores foliares de N, Mg, Cu e Zn, aumentaram exponencialmente com o teor de argila, da mesma forma que o DAP e a biomassa de folhas. Por outro lado, os teores foliares de P, K, Ca, S, B, Fe e Mn apresentaram relação oposta, decresceram exponencialmente nos solos mais argilosos. Foi obtida a calibração, a validação e aplicação do modelo 3-PGIS nas condições edafoclimáticas de Capão Bonito em povoamentos clonais do material genético C219H. No geral, o modelo 3-PGIS, apresentou bom desempenho, principalmente nas estimativas do volume de lenho com casca e da biomassa de fuste. As simulações do DAP e do IMA foram mais dispersas. / The study of the biological potential of forest ecosystems become essential when the objective is rational management, aiming productivity maximization, and avoiding resource exhaustion of the forest site. Forest sector usually apply models to simulate the future of the stand, aiming make appropriated decisions regarding the management to be followed. Among other models, 3-PG was tested for several forest species across different edaphoclimatic conditions, and has been reported unanimously, as a powerful tool to help on forest stands management. The objective of this study was: calibrate, validate and simulate productivity of clonal Eucalyptus plantations using 3-PG model integrated with a geographical information system. Twenty inventory plots were selected containing genetic material C219H (Eucalyptus grandis x E. urophylla) planted on spacing 3 x 3m, even aged, with planting date at 2000, Capão Bonito region, south of São Paulo state. On each plot were evaluated edaphic, dendrometric and nutritional variables on three average trees. Incorporation of relief characteristics resulted in differences on global radiation mapping, mainly during winter, where the effects of relief were elevated, showing up to 147% comparing to flat relief. Number of frosts per month was determined by monthly mean minimum temperature, with a negative linear relation. Most of soil variables evaluated showed a log-normal frequency distribution. At geostatistical analysis, variables related to soil fertility presented higher reaches of spatial dependency at A horizon, indicating higher homogeneity on nutrient distribution at superficial soil layer. The effective CEC showed positive exponential relation with wood volume. Parallel to that curve, we proposed an equation relating the fertility index of 3-PGIS and that soil attribute. Clay content showed strong influence on water levels at field capacity and wilting point, and as consequence, on soil water availability. Stem maximum biomass, observed on forest stands, managed with high technological standards, related directly with clay+silt contents. Same soil property affected wood density. High productivity sites, as consequence, with higher clay+silt contents, resulted in trees with lower wood density. Leaf level of N, Mg, Cu and Zn increased exponentially with clay content, like DBH and foliage biomass. Otherwise, leaf level of P, K, Ca, S, B, Fe and Mn showed opposite relation, decreasing exponentially on clayey soils. Calibration, validation and application of 3-PGIS were obtained for Capão Bonito edaphoclimatic conditions, on clonal stands of the genetic material C219H. Overall, 3- PGIS model showed good performance, mainly on estimative of stem plus bark volume and stem biomass. Simulations of DBH and MAI were dispersing.
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Modifications et restauration de propriétés physiques et chimiques de deux sols forestiers soumis au passage d'un engin d'exploitation / Changes and recovery in soil physical and chemical characteristics of two forest soils following traffic by a full-loaded forwarderGoutal, Noémie 27 March 2012 (has links)
Les risques de dégradation physique des sols forestiers sous l'effet de contraintes mécaniques externes liées à la mécanisation des opérations forestières, augmentent considérablement. Les mécanismes et le temps nécessaires à la restauration non assistée de la qualité des sols forestiers tassés restent encore peu étudiés, et leur identification nécessite de coupler les approches physiques, chimiques et biologiques. L'objectif de ce travail était d'étudier l'impact de la circulation d'un porteur forestier sur les conditions de l'enracinement (aération, régime hydrique et pénétrabilité) ainsi que son évolution à court terme. Ce travail s'appuie sur l'observation de deux sites expérimentaux mis en place dans le Nord Est de la France, concernant des sols de morphologie similaire (couche limono-argileuse de 50 cm d'épaisseur reposant sur un substrat argileux) et ayant subi des contraintes identiques. Des paramètres physiques (température et humidité du sol, densité apparente et résistance à la pénétration) et chimiques (composition de l'atmosphère du sol) ont été suivis pendant trois à quatre ans, à des fréquences allant d'un pas de temps quotidien à annuel. Le suivi du climat du sol et de la composition de son atmosphère a mis en évidence une diminution forte des conditions aérobies pendant un à un an et demi après le passage du porteur. Cet effet initial sur l'aération du sol a diminué subitement dès l'apparition de la première période de sécheresse édaphique, probablement grâce à la formation de fissures dans l'horizon de surface du sol tassé. Cependant un effet significatif du traitement sur la composition de l'atmosphère du sol pouvait toujours être observé trois à quatre ans après tassement. Pour suivre l'évolution des propriétés physiques du sol après circulation du porteur, il a été nécessaire d'opérer une normalisation par rapport à l'humidité au moment du prélèvement. Trois ou quatre ans après la circulation du porteur, une différence toujours significative existe entre les propriétés physiques des sols témoins et celles des sols tassés. Cependant une évolution de l'impact du porteur peut être mise en évidence dans la couche de surface (0–10 cm) des deux sites. Ce début de restauration se traduit, sur un des deux sites, par une différence entre traitement qui n'est plus significative quand les sols sont humides mais qui l'est encore quand les sols sont secs. Sur le deuxième site, cette différence a diminué quelle que ce soit l'humidité du sol. Ainsi, le début de régénération de la structure du sol perturbé ne s'accompagne pas d'une disparition de son comportement de prise en masse lors de son desséchement sur un des deux sites. Ce travail a permis de mettre en évidence une évolution des conséquences du porteur en surface du sol tassé qui serait liée à des processus physiques (gonflement –retrait, gel – dégel). Cependant, l'impact sur les conditions de l'enracinement (forte résistance à la pénétration quand les sols sont secs, faible aération quand ils sont humides) reste élevé de même que sur la résilience à long terme du peuplement. / Soil compaction belongs to the major treats to soil quality with no exceptions of forest ecosystems where the frequency and intensity of loads application increase since several decades. The mechanisms and the duration of soil quality recovery following heavy traffic in forests remain poorly documented and their study requires multidisciplinary approaches.The aim of this work was to evaluate the impact of forwarder traffic on the potential constraints to roots growth (aeration, water content, and penetrability) growing in two forest soils sensitive to compaction, and the evolution of these consequences in the short-term. This work is based on two experimental sites, set up in the northeast of France, with soils displaying similar morphologies (50 cm thick silt loam layer laying on a clayey layer) and having being loaded with the same forwarder under similar (wet) soil conditions. Soil climate (temperature and moisture), soil air composition, and soil bulk density and resistance to penetration were investigated continuously, monthly and yearly, respectively. Soil climate and air composition monitoring showed a strong initial decrease in aerobic conditions lasting one to one and a half year. The strong initial impact on soil aeration decreased concurrently with the first soil drought experimented at both sites, probably because of soil cracks formation in the disturbed soil. Yet heavy traffic still affected significantly soil air composition 3 to 4 years after compaction at both sites. To monitor changes in soil physical parameters, we had to standardize measures with regards to soil climatic conditions at the time of sampling. Three to four years after soil compaction, the difference in soil physical properties between treatments was still significant. However, changes in the impact of the forwarder traffic on soil physical characteristics could be stated in the surface layer (0–10 cm) of both sites. This beginning of soil restoration results at one of both sites in a difference between treatments that is no longer significant when soils are wet but that is still significant when the soils are dry. At the second site, the difference is still significant whatever soil moisture conditions but it has decreased since the start of the experiment. Consequently, this beginning of soil structure recovery is not accompanied by a disappearance of the hardsetting behaviour (decrease in hydrostructural stability) of the compacted soil at one site. In this study changes in the consequences of the forwarder traffic were stated in the surface soil layers of both sites, these changes may be due to physical processes (wetting – drying, freezing – thawing). Nevertheless, the impact remains strong on roots growth (high resistance to penetration when dry, poor gas transfer when wet) and on stand resilience to external stresses (drought, storm).
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Phosphorus in Preferential Flow Pathways of Forest Soils in Germany.Julich, Dorit, Feger, Karl-Heinz 27 March 2017 (has links)
The transport of nutrients in forest soils predominantly occurs along preferential flow pathways (PFP). This study investigated the composition of phosphorus (P) forms in PFPs and soil matrix in several temperate beech forests with contrasting soil P contents in Germany. The PFPs were visualized using dye tracer experiments. Stained and unstained soil was sampled from three profile cuts per plot and analyzed for P fractions. The results show that labile P concentrations were highest in the O-layer and had the same range of values at all sites (240–320 mg·kg−1), although total P (TP) differed considerably (530–2330 mg·kg−1). The ratio of labile P to TP was significantly lower in the P-rich soil compared to the medium and P-poor soils. By contrast, the ratio of moderately labile P to TP was highest at the P-rich site. The shifts in P fractions with soil depth were generally gradual in the P-rich soil, but more abrupt at the others. The contents of labile and moderately labile P clearly differed in PFPs compared to soil matrix, but not statistically significant. The studied soils are characterized by high stone contents with low potential for P sorption. However, indications were found that labile organically bound P accumulates in PFPs such as biopores.
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Tenazität und Desinfektion des Virus der Afrikanischen Schweinepest im WaldbodenTanneberger, Franziska 13 June 2022 (has links)
Die Dissertation befasst sich mit der Fragestellung der Tenazität sowie Desinfektion des Virus der Afrikanischen Schweinepest in verschiedenen Waldböden bei Kontamination durch infiziertes verendetes Schwarzwild. / The dissertation deals with the question of tenacity as well as disinfection of African swine fever virus in different types of forest soil in case of contamination by infected dead wild boar.
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Der Einfluss von Bodenschutzkalkungen auf die Lumbricidenfauna in sächsischen FichtenforstenPatzelt, Josephine 22 May 2019 (has links)
Zur Untersuchung des Einflusses der Bodenschutzkalkung gegen die flächendeckende Bodenversauerung im sächsischen Mittelgebirge wurde die Regenwurmfauna an acht Punkten der Bodenzustanderhebung (BZE-Punkte) im Erzgebirge und im Vogtland erfasst. Die Untersuchungspunkte sind durch Fichtenforste auf vier verschiedenen Lokalbodenformen charakterisiert, jeweils nicht gekalkt und gekalkt. Die verwendeten chemischen Daten stammen aus der Bodenzustandserhebung. Die Erfassung der Lumbriciden erfolgte mittels Elektroaustreibung und anschließender Handauslese, die Tiere wurden lebend und mit Darminhalt gewogen. Daraus wurden die Populationsparameter Individuendichte und Biomasse pro Quadratmeter ermittelt und mit dem U-Test nach Wilcoxon, Mann und Whitney auf signifikante Unterschiede geprüft. Bei Betrachtung der Daten der BZE fallen auf den gekalkten Flächen im Vergleich zu den nicht gekalkten Flächen der angehobene pH-Wert, die gesteigerte effektive Austauschkapazität (AKe) und die erhöhte Basensättigung (BS) im organischen Auflagehorizont sowohl in der Streu und in der fermentierten organischen Auflage (L + Of) als auch in der humifizierten organischen Auflage (Oh) auf. [...] Das C/N-Verhältnis weist in keinem der Horizonte einen offensichtlichen Zusammenhang zur Kalkung auf. Auf den gekalkten Flächen wurde sowohl eine höhere Individuendichte als auch eine höhere Biomasse der Lumbriciden festgestellt. Die Unterschiede sind zu verschiedenen Niveaus signifikant. Zwischen den Populationparametern und pH-Wert, AKe und Basensättigung besteht kein linearer Zusammenhang, bei erhöhten Werten dieser Bodenchemie-Komponenten wurden jedoch höhere Individuendichten und Biomassen festgestellt. Zum C/N-Verhältnis konnte keine Beziehung festgestellt werden. Auf den gekalkten Flächen wurden auch mehr Arten als auf den nicht gekalkten gezählt. [...] Es ist zu überlegen, inwieweit sich (Wieder-)Ansiedelungsmaßnahmen entsprechender Arten durchführen ließen.:1 Einleitung und Zielstellung ...........................................................................6
2 Grundlagen und Methodik ...........................................................................9
2.1 Naturraum ................................................................................................9
2.2 Regenwurmbiologie ................................................................................13
2.3 Methodik .................................................................................................18
2.4 Statistik ...................................................................................................21
3 Ergebnisse .................................................................................................23
3.1 Chemische Daten der Bodenzustandserhebung ....................................23
3.2 Individuendichte und Biomasse ..............................................................28
3.3 Zusammenhänge zur Bodenchemie .......................................................32
3.4 Artenfunde .............................................................................................42
4 Diskussion ..................................................................................................43
4.1 Kritik an der Methodik und der statistischen Auswertung .......................43
4.2 Ergebnisbewertung ................................................................................45
5 Zusammenfassung und Fazit ......................................................................49
6 Abstract .......................................................................................................51
7 Literaturverzeichnis .....................................................................................52
Anhang ...........................................................................................................62 / Since the end of the last century, liming is a common melioration measure in German forest and wood management against the acidity of soils, especially in the uplands like the Ore Mountains (Erzgebirge) in Saxony. To record changes in ecosystems, there are different monitoring programms, for example the 'Bodenzustandserhebung (BZE)'. But also a biological component for detecting effects of liming on flora and fauna is needed. Earthworms are a very important group of the soil fauna. Therefore, this study was aimed at this family to track their reaction to liming in spruce forests in the Saxon Ore Mountains. The expectation of a positive reaction could be significantly approved on the basis of four paired habitats, each couple with a not limed and a limed counter-part. Four species of earthworms were recorded. Three of them are epigeic forms, one is an endogeic type. Important factors for their abundance and biomass are pH, exchange capacity of cations and saturation of bases. A linear correlation was not detected. In this study, the ratio of carbon and nitrogen in soils showed a link neither to lime nor to earthworms abundance or biomass. As a result, liming is a reasonable measure to reactivate the biological components in acid affected soils, but it is also needed to cultivate a more various forest ecosystem.:1 Einleitung und Zielstellung ...........................................................................6
2 Grundlagen und Methodik ...........................................................................9
2.1 Naturraum ................................................................................................9
2.2 Regenwurmbiologie ................................................................................13
2.3 Methodik .................................................................................................18
2.4 Statistik ...................................................................................................21
3 Ergebnisse .................................................................................................23
3.1 Chemische Daten der Bodenzustandserhebung ....................................23
3.2 Individuendichte und Biomasse ..............................................................28
3.3 Zusammenhänge zur Bodenchemie .......................................................32
3.4 Artenfunde .............................................................................................42
4 Diskussion ..................................................................................................43
4.1 Kritik an der Methodik und der statistischen Auswertung .......................43
4.2 Ergebnisbewertung ................................................................................45
5 Zusammenfassung und Fazit ......................................................................49
6 Abstract .......................................................................................................51
7 Literaturverzeichnis .....................................................................................52
Anhang ...........................................................................................................62
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Contenu total en éléments traces de sols forestiers du Québec méridionalMasse, Jacynthe 06 1900 (has links)
Les sols forestiers constituent un réservoir considérable d’éléments nutritifs disponibles pour soutenir la productivité forestière. Ces sols contiennent aussi une quantité, encore inconnue à ce jour, d’éléments traces biodisponibles provenant de sources anthropiques ou naturelles. Or, plusieurs de ces éléments recèlent un potentiel toxique pour les organismes vivants. Ainsi, la quantification de la concentration et du contenu total en éléments traces des sols forestiers s’avère nécessaire afin d’évaluer les impacts des perturbations sur la qualité des sols.
Les objectifs de ce projet de recherche sont: 1) de mesurer le contenu total en éléments traces en phase solide (Ag, As, Ba, Cd, Ce, Co, Cr, Cu, Mn, Ni, Pb, Rb, Se, Sr, Tl, V, Y, Zn) des divers horizons de sols d’écosystèmes forestiers du Québec méridional; 2) d’établir des liens significatifs entre la fraction soluble dans l’eau des éléments traces et les propriétés des horizons de sols et; 3) d’évaluer le rôle de la proximité d’un centre urbain sur les contenus en éléments traces. Pour répondre à ces objectifs, quatre profils de sols situés dans la région de St-Hippolyte et deux situés dans la région de Montréal furent échantillonnés jusqu'à l'atteinte du matériel parental.
Les résultats de ce projet de recherche ont révélé que le contenu total en éléments traces présents dans les profils de sols se retrouve en grande partie dans les fragments grossiers du sol. Il a été démontré que la teneur en carbone organique, les complexes organométalliques et les oxydes de fer et d’aluminium dictent la distribution en profil de la majorité des éléments traces étudiés. Finalement, il fut prouvé que la région de Montréal présente des niveaux de contamination en éléments traces (Ag, As, Ba, Cu, Mn, Pb, Rb, Se, Sr, Tl et Zn) supérieurs à ceux rencontrés dans les Laurentides. / Forest soils represent an important stock of nutrients available to sustain forest productivity. They also contain an amount, still unknown, of trace elements inherited from natural or anthropogical sources. Many of these trace elements can be toxic to living organisms. Thereby, quantification of the concentration and the total content of trace elements in forest soils is necessary to asses the impact of these elements on soil quality.
The specific objectives of this research project are: 1) to measure the total content of trace elements in solid phase (Ag, As, Ba, Cd, Ce, Co, Cr, Cu, Mn, Ni, Pb, Rb, Se, Sr, Tl, V, Y, Zn) of various soil horizons in two forest ecosystems of southern Quebec, 2) to establish significant correlations between the bioavailable fraction (water-soluble) of trace elements and soil horizons properties and 3) to compare the trace element stock of two Canadian Shield’s forest soil with those of similar soils situated in the Montreal area. To achieve these goals four soil profiles situated in the pristine region of St-Hippolyte and two in the urban area of Montréal, were excavated down to the parent material.
The results of this research have established that the trace element’s total stock is mainly concentrated in coarse fragments of the soil. Multivariate statistical analyses revealed significant links between organic carbon, organometallic complexes as well as Fe-Al oxides and the distribution of trace element in soil profiles. Finally, it was proved that Montreal’s soil contained more trace element (Ag, As, Ba, Cu, Mn, Pb, Rb, Se, Sr, Tl et Zn) than Canadian Shield’s soils.
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Valutazione di parametri chimico-fisici e microbiologici di una sugherata sarda e aspetti fenologici relativi alla fioritura di Quercus suber L.NOVELLI, ELISA 24 February 2011 (has links)
La presente tesi di dottorato ha trattato due diversi aspetti specifici ricollegabili all’ambiente della foresta di querce da sughero ed alla specie arborea Quercus suber L.
La prima parte ha riguardato la valutazione pedologica della Sughereta Sperimentale di “Cusseddu – Miali – Parapinta”, situata a Tempio Pausania (OT) in Sardegna, che ha rappresentato il primo esempio di sughereta munita di Certificazione Forestale FSC, a livello mondiale, ed è stata effettuata nell’ambito del Progetto NATO Scienza per la Pace (ESP.MD.SFP 981674)0073. Tale progetto ha coinvolto un consorzio interdisciplinare, composto da gruppi di ricerca provenienti da tre paesi NATO (Portogallo, Inghilterra e Italia) e da due paesi del Dialogo Mediterraneo (Marocco e Tunisia).
Lo scopo di questa prima parte ha riguardato la valutazione della qualità del suolo come espressione della capacità di interagire con l’ecosistema in funzione della produttività biologica e della gestione forestale.
La seconda parte,invece, ha riguardato la fenologia della fioritura in Quercus suber L., prendendo in esame individui della Sughereta “Quinta da Serra”, Azeitão, Lisbona (Portogallo), con l’obiettivo di approfondire le conoscenze sulla variabilità all’interno della specie Quercus suber L. e il comportamento riproduttivo durante il periodo di fioritura, e di avanzare l’ipotesi di un modello di risposta di adattamento ai cambiamenti climatici. / In this PhD thesis two different aspects that specifically relate to the environment of cork oak forest and the species Quercus suber L. were examined. The first part was focused on the soil’s evaluation of Experimental cork producing area named "Cusseddu–Miali-Parapinta”, located in Tempio Pausania (OT) in Sardinia which represent the first example of cork oak forest certificated (FSC) in the world. This aspect was carried out within the framework “NATO Science for Peace Project (ESP.MD.SFP 981674) 0073”, which involved an interdisciplinary consortium, comprising research teams from three NATO countries(Portugal, England and Italy) and two Mediterranean Dialogue countries (Morocco and Tunisia). The purpose of this first part was focused on the evaluation of soil quality as expression of the ability to interact with the ecosystem as a function of biological productivity and forest management. The second part, involved in the flowering phenology of the Quercus suber L., examining individuals of cork oak in "Quinta da Serra", Azeitão, Lisbon (Portugal), with the final aim of increasing knowledge on the variability within the species Quercus suber L. and the reproductive behavior during the flowering period, and put forward the hypothesis of a model of adaptive response to climate change.
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