Ziel des Forschungsprojektes war der Gewinn umfassender verjüngungsökologischer Kenntnisse zu den Pionierbaumarten Sandbirke (Betula pendula Roth), Salweide (Salix caprea L.) und Eberesche (Sorbus aucuparia L.) im Hinblick auf eine natürliche, eingriffsfreie Wiederbewaldung von Schadflächen (z.B. nach Sturmwurf). Die Abschätzung des Besiedlungserfolges von Schadflächen durch Pionierbaumarten ist aufgrund unzureichender verjüngungsökologischer Kenntnisse gegenwärtig noch mit großen Unsicherheiten verbunden. Die Untersuchungen fanden auf fünf 4-12 ha großen Kyrill-Sturmwurfflächen in den Hoch- und Kammlagen (750-900 m ü. NN) des Thüringer Waldes statt. Alle potenziellen Samenbäume der Pionierbaumarten wurden in den angrenzenden, geschlossenen Fichtenbeständen lokalisiert. Als Versuchsdesign wurde in Abhängigkeit der vorgefundenen Samenbaumdichten und -verteilungen ein Kreuz- bzw. Sterntransekt auf den Sturmwurfflächen etabliert. Entlang der Transektlinien wurden alle 20 m Samenfallen installiert. Als Samenfallen kamen für die Sandbirke Netztrichterfallen (0,2 m²), für die Salweide Klebfallen (0,043 m²) und für die endozoochore Ausbreitung durch frugivore Vogelar-ten Kotfallen (0,25 m²) zum Einsatz. Für die Modellierung der Samenausbreitung von Sandbirke und Salweide wurden inverse Modelle bzw. geostatistische Modelle erstellt. Zudem wurden auf einer der Sturmwurfflächen genetische Nachkommenschaftsanalysen bei Sal-weide mittels Kern-DNA-Primer durchgeführt. Die Bodensamenbankuntersuchungen fanden in jeweils drei geschlossenen Birkenbeständen, Fichten-Birken-Beständen, Fichtenbeständen mit einer einzeln eingemischten Birke und reinen Fichtenbeständen im Tharandter Wald und Thüringer Wald statt. Mittels eines 10,2 cm breiten Stechzylinders wurden 10 cm tiefe Bodenproben gewonnen. Die Lagerung der Proben fand im Kaltgewächshaus statt, wo alle 14 d die gekeimten Samen erfasst wurden. Weiterhin wurde ein Eingrabungsexperiment installiert. Dafür wurden Sandbirkensamen, Ebereschensamen und Ebereschenfrüchte in 2 cm, 5 cm und 10 cm tiefen Mineralboden vergraben und in sechsmonatigen Intervallen jeweils eine Keimprobe zum Test der verbliebenen Keimfähigkeit entnommen. Die Auswertung der Bodensamenbankuntersuchungen erfolgte mittels GLM und GLMM. Während der zweijährigen Untersuchung zur zeitlichen und räumlichen Samenausbreitung von Salix caprea auf fünf Sturmwurfflächen konnten ein schwächeres und ein stärkeres Samenjahr nachgewiesen werden. Des Weiteren erstreckte sich der Samenflugzeitraum im Frühjahr in Abhängigkeit von den klimatischen Bedingungen über 12 Wochen in 2015 und 6 Wochen in 2016. Die höchsten Samenmengen von 23-156 Samen je Falle wurden jeweils unter den Kronen von Salweiden-Samenbäumen nachgewiesen. Ab einer Entfernung von 350 m zum Samenbaum bis zur untersuchten Distanz von 870 m wurden, unabhängig von der Distanz, der Hangneigung, der Anzahl der Samen-bäume und der Windrichtung (Anisotropie), im Durchschnitt 0,6-2,1 Samen je Falle er-fasst. Die genetischen Analysen zur Nachkommenschaft ergaben, dass 29 % der untersuch-ten Verjüngungspflanzen von einem der 20 lokalisierten Elternbäume in der bewaldeten, 500 m breiten Suchzone abstammten. Die Ausbreitungsdistanzen der nachweislich am erfolgreichsten verjüngten Samenbäume betrugen dabei 550-800 m. Insgesamt zeigte die Salweidenverjüngung eine höhere Allel-Variation, als die 20 Elternbäume, was auf einen externen Genfluss und lange Samen- und Pollenausbreitungsdistanzen hinweist. Im Zuge des zweijährigen Untersuchungszeitraums zur Samenausbreitung von Betula pendula auf zwei Kyrill-Sturmwurfflächen konnten ein Mastjahr und ein Zwischenjahr nachgewiesen werden. Die Ergebnisse der inversen Modellierung mittels isotroper Mo-delle ergaben dabei flächenunabhängig Produktionsmengen für einen Samenbaum von 20 cm im Bhd von 300.000-366.000 Samen je Baum im Zwi-schenjahr 2015 und 1.430.000-1.530.000 Samen je Baum im Mastjahr 2016. Mittels räumlicher Modellierung der Samenausbreitung konnte keine Anisotropie belegt werden. Unabhängig von den beprobten Flächen und Un-tersuchungsjahren, belegen die Modellschätzungen allesamt eine isotrope Ausbreitung der Samen. Die mittleren Ausbreitungsdistanzen (MDD) beliefen sich dabei hangaufwärts auf 86-97 m und hangabwärts auf 367-380 m. Maximal ab-gelagerte Samendichten von 2.015 n m-² im Zwischenjahr und 9.557 n m-² im Mastjahr fanden sich bis 40-50 m Entfernung zum Samenbaum. Die Untersuchungen der endozoochoren Samenausbreitung auf fünf Sturmwurfflächen weisen auf eine bevorzuge Nutzung der Vogelarten von Rast- und Sitzgelegenheiten (Strukturelemente) auf Freiflächen zum Absetzen von Kot hin (2,7 Kothaufen je m²). Unter Freiflächenbedingungen - ohne Strukturelemente - ergaben sich im Mittel 0,4 Kothaufen je m². Die höchsten mittleren Kotdichten wurden unter aufra-genden Totästen (20 n m-²), umgeklappten Wurzeltellern (4,6 n m-²) und Hochstubben (3,9 n m-²) nachgewiesen. Schwach dimensionierte Verjüngungspflanzen der Sandbirke, Eberesche und Fichte, und Strukturelemente unter einem Meter Höhe wurden dagegen weitgehend für das Absetzen von Kot gemieden. Das Vermögen zum Aufbau einer Bodensamenbank durch Betula pendula und Sorbus aucuparia unterschied sich deutlich. 56-100 % der eingegrabenen Sandbirkensamen wa-ren auch nach 2,5 Jahren keimfähig, wohingegen lediglich 3-16 % der eingegrabenen Ebereschensamen ohne Fruchthülle und 0-19 % der eingegrabenen Ebereschensamen mit Fruchthülle vital waren. Die Auswertung mittels GLM prognostizierte einen kom-pletten Verlust der Keimfähigkeit nach 12 Jahren, 4,5 Jahren und 3 Jahren der Sandbirkensamen, sowie der Ebereschensamen mit und ohne Fruchthülle. Ein Einfluss der Lagerungstiefe war nur für Sandbirke nachweisbar. Die Untersuchungen der Bodensamenbank von Birke in Fichtenbeständen mit unter-schiedlichen Birkensamenbaumanteilen ergab einen straffen Zusammenhang zwischen der Anzahl von Samenquellen und den nachgewiesenen Samendichten im Boden. In den Birkenbeständen fanden sich stets die höchsten Dichten von 489-1.142 Birkensamen je m². Die Analyse unterschiedlicher Bodenschichten zeigte zudem signifikant abneh-mende Birkensamendichten mit zunehmender Bodentiefe. Die Ergebnisse der Untersuchungen zeigen, dass die Fruktifikation von Betula pendula, Salix caprea und Sorbus aucuparia durch klimatische Verhältnisse beeinflusst wird, weshalb die drei Pionierbaumarten nicht alljährlich hohe Samenmengen produzieren (Mastjahre und Zwischenjahre). Zum Ausgleich von Produktionsdefiziten in den Zwischenjahren unter-scheiden sich die Pionierbaumarten in ihrer Strategie. Dies gilt es bei der Umsetzung des Konzeptes einer natürlichen, eingriffsfreien Wiederbewaldung von Schadflächen nach Sturmwurf durch die Naturverjüngung von Pionierbaumarten zu beachten. Die einzige der drei Pionierbaumarten, die dem allgemeinen Bild einer Pionierbaumart ent-spricht, ist die Salweide. Ihr Besiedlungserfolg ist allein von den aktuellen, alljährlich variierenden, aber dennoch stets hohen Samenproduktionsmengen und den enorm weiten Aus-breitungsdistanzen (>800 m) abhängig. Hinsichtlich der Samenausbreitung haben die Him-melsrichtung, die Position der Samenbäume und die Anzahl vorhandener Samenquellen ab einer Distanz von 50 m zur Schadfläche keinen bedeutenden Einfluss auf die abgelagerten Samenmengen mehr. Die auf 86-380 m limitierte Samenausbreitung von Sandbirke wurde dagegen stark vom Geländerelief (Hangneigung), der Position der Samenbäume (Tal, Kuppe, Hanglage) und der Distanz der Samenbäume zur Sturmwurffläche beeinflusst. Zum Ausgleich der limitierten Samenausbreitung und deutlich reduzierten Samenmengen im Zwischenjahr ist Sandbirke jedoch zum Aufbau einer short-term persistenten Bodensamenbank befähigt. Den gesamten Verjüngungszyklus betrachtend entspricht die Eberesche eher einer Schluss-waldbaumart. Unter ungünstigen klimatischen Bedingungen kommt es häufig zum kompletten Ausfall der Samenproduktion. Ihr enormes Wiederbewaldungspotential von Sturmwurfflächen speist sich hauptsächlich aus dem Aufbau einer Sämlingsbank und weni-ger durch den aktuellen Samenregen oder der short-term persistenten Bodensamenbank. Die limitierte Samenausbreitung von Sandbirke und Eberesche macht eine „räumliche Optimierung“ der Samenbaumpositionen durch die Forstwirtschaft erforderlich. Aufgrund der allgegenwärtigen Omnipräsenz von Weidensamen ist dies für Salweide nicht zwingend not-wendig. Das detailreiche Wissen zur Verjüngungsökologie der untersuchten Pionierbaumar-ten ermöglicht eine gezielte waldbauliche Steuerung im Sinne des Vorhalts und der Pflege von Pionierbaumarten im Wirtschaftswald. Dies ist gegenwärtig und zukünftig vor allem von besonderer Bedeutung, da aufgrund der zu erwartenden Zunahme von Schadereignissen und deren Unvorhersehbarkeit die Fähigkeit der Wälder zur natürlichen Wiederbewaldung von Schadflächen durch Pionierbaumarten zunehmend an Interesse gewinnen wird.:Table of abbreviations III Summary IV Zusammenfassung VIII Chapter 1 – General introduction 1 1.1 Introduction 2 1.1.1 Importance and relevance of the study 2 1.1.2 Research interest - regeneration ecology 5 1.3 Aims, scope and hypotheses 9 1.4 Study outline 12 1.5 References 13 Chapter 2 – Seed dispersal capacity of Salix caprea L. assessed by seed trapping and parentage analysis 25 2.1 Abstract 26 2.2 Introduction 26 2.3 Materials and methods 29 2.3.1 Study area 29 2.3.2 Experimental design 31 2.3.3 Genetic analysis 32 2.3.4 Seed trap data analysis 33 2.3.5 Geostatistical models 34 2.4 Results 36 2.4.1 Temporal patterns of seed dispersal 37 2.4.2 Dispersal distance and spatial patterns of seed dispersal 37 2.4.3 Genetic parentage analysis 40 2.5 Discussion 42 2.5.1 Seed production and temporal patterns of seed dispersal 42 2.5.2 Dispersal distance and spatial patterns of seed dispersal 43 2.5.3 Genetic parentage analysis 45 2.6 Conclusions for silvicultural practice 46 2.7 References 48 Chapter 3 – Restrictions on natural regeneration of storm-felled spruce sites by silver birch (Betula pendula Roth) through limita-tions in fructification and seed dispersal 57 3.1 Abstract 58 3.2 Introduction 58 3.3 Materials and methods 60 3.3.1 Study area 60 3.3.2 Experimental design 63 3.3.3 Data analysis 64 3.3.4 Seed dispersal model 64 3.3.5 Simulations for practical management decisions 66 3.4 Results 66 3.4.1 Seed production 66 3.4.2 Seed dispersal and spatial patterns 68 3.5 Discussion 71 3.5.1 Seed production 71 3.5.2 Directionality 72 3.5.3 Spatial patterns and seed dispersal distances 72 3.6 Seed dispersal scenarios for silvicultural management decisions 74 3.6.1 Seed dispersal scenarios 74 3.6.2 Conclusions for silvicultural management decisions 76 3.7 References 78 Chapter 4 – The impact of structural elements on storm-felled sites on endozoochorous seed dispersal by birds – a case study 85 4.1 Abstract 86 4.2 Introduction 86 4.3 Materials and methods 88 4.3.1 Study area 88 4.3.2 Experimental design 90 4.3.3 Data analysis 91 4.4 Results 92 4.5 Discussion 95 4.6 Conclusions for silvicultural practice 97 4.7 References 98 Chapter 5 – Soil seed banks of pioneer tree species in European tempe-rate forests: a review 104 5.1 Abstract 105 5.2 Introduction 105 5.3 Methods of literature search 107 5.4 Species-specific reproductive ecology determining the potential of soil seed banks 110 5.5 Characterization and classification of soil seed banks 112 5.5.1 Soil seed bank of Betula spp. 114 5.5.2 Soil seed bank of Alnus glutinosa (L.) GAERTN. 116 5.5.3 Soil seed banks of Salix spp. and Populus tremula L. 117 5.5.4 Soil seed bank of Sorbus aucuparia L. 118 5.6 Conclusions 119 5.7 References 120 Chapter 6 – Do birch and rowan establish soil seed banks sufficient to compensate for a lack of seed rain after forest disturbance? 134 6.1 Abstract 135 6.2 Introduction 135 6.3 Materials and methods 137 6.3.1 Study areas 137 6.3.2 Data collection 139 6.3.3. Statistical analysis 140 6.4 Results 141 6.4.1 Study A - Artificial seed burial experiment 141 6.4.2 Study B - Soil core sampling in the forest 145 6.5 Discussion 147 6.5.1 Study A - Artificial seed burial experiment 147 6.5.2 Study B - Soil core sampling in the forest 149 6.6 Conclusions 151 6.7 References 152 Chapter 7 – General discussion 160 7.1 Discussion of important aspects of regeneration ability 161 7.1.1 Fructification and seed production in Salix caprea, Betula pendula and Sorbus aucuparia 165 7.1.2 Ecological processes within the regeneration cycle of Salix caprea 167 7.1.3 Ecological processes within the regeneration cycle of Betula pendula 168 7.1.4 Ecological processes within the regeneration cycle of Sorbus aucuparia 169 7.2. Conclusions for silviculture and management recommendations 172 7.3 References 175 Table of appendix i / The aim of the study was to obtain comprehensive knowledge of the regeneration ecology of the pioneer tree species silver birch (Betula pendula Roth), goat willow (Salix caprea L.) and rowan (Sorbus aucuparia L.). The findings should contribute to better management of the natural regeneration of disturbed sites (e.g., windthrown sites) by pioneer tree species. Insufficient knowledge of the regeneration ecology of pioneer tree species renders forest managers’ abilities to assess the success of regeneration of windthrown sites uncertain. The study took place in the years 2015 and 2016. The study sites were located on the slopes and mountain tops (plateaus) of the Thuringian Forest (715-900 m a.s.l.), on five windthrown open areas (4-13 ha) created by the storm ‘Kyrill’ in January 2007. All seed trees of pioneer tree species were mapped within the forested search zone around each site. This zone extended 200 m for silver birch and rowan and 500 m for goat willow. Following the mapping of these seed trees and an analysis of their spatial distribution, seed traps were placed along two or four crossing line transects, with intervals of 20 m between traps. The traps were funnel shaped net seed traps for silver birch (0.2 m²), seed traps with a sticky, non-drying glue for goat willow (0.043 m²) and dropping traps for seeds dispersed endozoochorously by frugivorous birds (0.25 m²). A phenomenological model and model-based geostatistics were used to investigate silver birch and goat willow seed dispersal. For goat willow a parentage analysis was performed at one of the study sites using nuclear-DNA-primers. The soil seed bank study was carried out in three birch stands, spruce stands with admixed birch, spruce stands with one isolated birch tree and pure spruce stands in the Tharandter Forest and in the Thuringian Forest. Soil core samples with a diameter of 10.2 cm were taken from the litter layer and the mineral soil to a depth of 10 cm. The soil samples were placed in a greenhouse and seed germination was checked every 14 days. An artificial seed burial experiment was also carried out. Silver birch seeds, rowan seeds and rowan fruits were buried in mineral soil at depths of 2 cm, 5 cm and 10 cm. At intervals of 6 months sample sets were removed from the soil and the germination capacity checked. The analysis of the soil seed banks was based on generalized linear mixed models (GLMM) and generalized linear models (GLM). The 2-year study of the temporal and spatial dispersal of seeds of Salix caprea on five Kyrill-felled areas involved one year with lower seed production and one with more bountiful seed production. The duration of the spring seed rain was about 12 weeks in 2015, and only 6 weeks in 2016 because of contrasting weather conditions. The highest seed numbers of 23-156 n per trap occurred close to the base of the seed trees. Beyond 350 m from the seed trees, up to the maximum distance in the study of 870 m, the average numbers of seeds per trap (0.6-2.1 seeds) were independent of the dispersal distance, inclination, the number of seed sources and the dispersal direction (anisotropy). Parentage analyses showed that 29% of the saplings stemmed from one of the 20 parent trees within the 500 m search zone extending from the edge of the open area. The seed dispersal distances of the most successful seed parents were between 550-800 m. The saplings revealed a higher allelic variation than the 20 parent trees, indicating external gene flow and long seed and pollen dispersal distances. During the 2-year study of Betula pendula seed dispersal on two Kyrill-felled areas there was a mast year and a non-mast year. Independent of the site, the seed production rate of a silver birch seed tree with a mean diameter at breast height (dbh) of 20 cm predicted by isotropic inverse models was approximately 300,000-366,000 seeds in 2015 and 1,430,000-1,530,000 seeds per tree in the mast year 2016. Directionality (anisotropic inverse modelling) of seed dispersal around an individual seed tree could not be confirmed. The model results revealed the isotropic model (no directionality) to be an appropriate approach for all sites and years. The mean dispersal distances (MDD) were 86 m and 97 m (uphill) and 367 m and 380 m (downhill). The maximum seed numbers occurred within 40-50 m of a seed tree, amounting to 2,015 n m-² in the non-mast year and 9,557 n m-² in the mast year. The study of endozoochorous seed dispersal on the five sites felled by the storm Kyrill showed a preference of frugivorous birds for perches and resting places (structural elements) from which to defecate onto open areas (2.7 droppings per m²). On completely open areas – with no structural elements – an average of 0.4 droppings per m² was recorded. The highest mean bird dropping density was observed under towering dead branches (20 n m-²), upturned root plates (4.6 n m-²) and high stumps (3.9 n m-²). Young, small diameter silver birch, rowan and spruce trees, and structural elements less than 1 m in height generally, were avoided by frugivorous birds as a place from which to defecate. The abilities of Betula pendula and Sorbus aucuparia to form a soil seed bank differed. Between 56-100 % of the buried silver birch seeds were still viable after 2.5 years, whereas only 3-16 % of the rowan seeds buried without pulp and 0-19 % of the rowan seeds within pulp were viable. The maximum durations of storage in the soil predicted for silver birch seeds and rowan seeds with and without pulp by GLM were 12 years, 4.5 years and 3 years. An influence of the storage depth was found for silver birch seeds only. The investigation of the soil seed banks of birch in three birch stands and nine spruce forests with different numbers of admixed birch seed trees showed a strong correlation between the number of seed sources and the seed density in the soil. The birch stands contained the highest mean densities of viable birch seeds in soil, between 489-1,142 n m-². The analysis of the different soil layers showed significantly declining birch seed densities with increasing soil depth across all sites. The results of the study showed that the fructification of Betula pendula, Salix caprea and Sorbus aucuparia is influenced by weather conditions, with the three pioneer tree species failing to produce high numbers of seeds every year (mast and non-mast years). The three species differed in their strategies to compensate for low seed production in non-mast years. This must be considered when implementing a concept for the reforestation of disturbed sites based on natural regeneration by pioneer tree species. Goat willow was the only one of the three specie studied with characteristics corresponding to the general assumptions made about pioneer tree species. The regeneration success of goat willow is dependent upon the variable but generally high annual seed production and long seed dispersal distances (> 800 m). The azimuth direction, position and number of seed trees have no meaningful influence on seed numbers at a distance of more than 50 m from the seed source. The limited mean seed dispersal distances of 86-380 m determined for silver birch were influenced by site inclination, the seed tree location (valley, slope or plateau) and the distance between the seed tree and the windthrown site. Silver birch seed shadow is also influenced by the number of seed sources. To compensate for the limited dispersal distances and the significantly lower seed production in non-mast years, silver birch is able to build up a short-term persistent soil seed bank. The regeneration cycle of rowan is more reminiscent of that of a shade-tolerant tree species. Unfavorable weather conditions often result in a complete failure to produce seeds. The enormous regeneration potential of rowan on disturbed sites stems primarily from a seedling bank, which is built up over years. The seed rain in any given year and its short-term persistent soil seed bank are of secondary importance. Forest management targeting a ‘spatial optimization’ of silver birch and rowan seed trees is necessary to ensure successful natural regeneration given the limited seed dispersal. The omnipresence of goat willow seeds renders specific spatial management measures for its establishment unnecessary. Detailed knowledge of the regeneration ecology of the studied pioneer tree species makes possible an approach to silviculture that is targeted to the conservation and revitalization of pioneer tree species in managed forests. The expected increase in the frequency of disturbances, and their unpredictability, means that the ability of forests to naturally regenerate using pioneer tree species is likely to grow in importance.:Table of abbreviations III Summary IV Zusammenfassung VIII Chapter 1 – General introduction 1 1.1 Introduction 2 1.1.1 Importance and relevance of the study 2 1.1.2 Research interest - regeneration ecology 5 1.3 Aims, scope and hypotheses 9 1.4 Study outline 12 1.5 References 13 Chapter 2 – Seed dispersal capacity of Salix caprea L. assessed by seed trapping and parentage analysis 25 2.1 Abstract 26 2.2 Introduction 26 2.3 Materials and methods 29 2.3.1 Study area 29 2.3.2 Experimental design 31 2.3.3 Genetic analysis 32 2.3.4 Seed trap data analysis 33 2.3.5 Geostatistical models 34 2.4 Results 36 2.4.1 Temporal patterns of seed dispersal 37 2.4.2 Dispersal distance and spatial patterns of seed dispersal 37 2.4.3 Genetic parentage analysis 40 2.5 Discussion 42 2.5.1 Seed production and temporal patterns of seed dispersal 42 2.5.2 Dispersal distance and spatial patterns of seed dispersal 43 2.5.3 Genetic parentage analysis 45 2.6 Conclusions for silvicultural practice 46 2.7 References 48 Chapter 3 – Restrictions on natural regeneration of storm-felled spruce sites by silver birch (Betula pendula Roth) through limita-tions in fructification and seed dispersal 57 3.1 Abstract 58 3.2 Introduction 58 3.3 Materials and methods 60 3.3.1 Study area 60 3.3.2 Experimental design 63 3.3.3 Data analysis 64 3.3.4 Seed dispersal model 64 3.3.5 Simulations for practical management decisions 66 3.4 Results 66 3.4.1 Seed production 66 3.4.2 Seed dispersal and spatial patterns 68 3.5 Discussion 71 3.5.1 Seed production 71 3.5.2 Directionality 72 3.5.3 Spatial patterns and seed dispersal distances 72 3.6 Seed dispersal scenarios for silvicultural management decisions 74 3.6.1 Seed dispersal scenarios 74 3.6.2 Conclusions for silvicultural management decisions 76 3.7 References 78 Chapter 4 – The impact of structural elements on storm-felled sites on endozoochorous seed dispersal by birds – a case study 85 4.1 Abstract 86 4.2 Introduction 86 4.3 Materials and methods 88 4.3.1 Study area 88 4.3.2 Experimental design 90 4.3.3 Data analysis 91 4.4 Results 92 4.5 Discussion 95 4.6 Conclusions for silvicultural practice 97 4.7 References 98 Chapter 5 – Soil seed banks of pioneer tree species in European tempe-rate forests: a review 104 5.1 Abstract 105 5.2 Introduction 105 5.3 Methods of literature search 107 5.4 Species-specific reproductive ecology determining the potential of soil seed banks 110 5.5 Characterization and classification of soil seed banks 112 5.5.1 Soil seed bank of Betula spp. 114 5.5.2 Soil seed bank of Alnus glutinosa (L.) GAERTN. 116 5.5.3 Soil seed banks of Salix spp. and Populus tremula L. 117 5.5.4 Soil seed bank of Sorbus aucuparia L. 118 5.6 Conclusions 119 5.7 References 120 Chapter 6 – Do birch and rowan establish soil seed banks sufficient to compensate for a lack of seed rain after forest disturbance? 134 6.1 Abstract 135 6.2 Introduction 135 6.3 Materials and methods 137 6.3.1 Study areas 137 6.3.2 Data collection 139 6.3.3. Statistical analysis 140 6.4 Results 141 6.4.1 Study A - Artificial seed burial experiment 141 6.4.2 Study B - Soil core sampling in the forest 145 6.5 Discussion 147 6.5.1 Study A - Artificial seed burial experiment 147 6.5.2 Study B - Soil core sampling in the forest 149 6.6 Conclusions 151 6.7 References 152 Chapter 7 – General discussion 160 7.1 Discussion of important aspects of regeneration ability 161 7.1.1 Fructification and seed production in Salix caprea, Betula pendula and Sorbus aucuparia 165 7.1.2 Ecological processes within the regeneration cycle of Salix caprea 167 7.1.3 Ecological processes within the regeneration cycle of Betula pendula 168 7.1.4 Ecological processes within the regeneration cycle of Sorbus aucuparia 169 7.2. Conclusions for silviculture and management recommendations 172 7.3 References 175 Table of appendix i

Les vaccins thérapeutiques anti-tumoraux reposent sur l’activation du système immunitaire adaptatif et sont basés sur la reconnaissance des antigènes tumoraux (AT) par les lymphocytes T auxiliaires et cytotoxiques spécifiques. Leur efficacité nécessite une sélection méticuleuse des antigènes cibles ainsi qu’une présentation antigéniques par le CMH de classe I (CMH-I) dans les tumeurs non modifiée. Alors que l’attention s’est d’abord portées uniquement sur les AT dérivés de séquences exoniques, ceux dérivés d’évènements de traduction alternatifs ont été montrés comme ayant un fort potentiel en tant que cibles. Ces derniers peuvent dérivés d’une traduction de séquences dîtes « non traduites », initiée par des codons alternatifs ou dans un cadre de lecture non canonique. Une telle traduction alternative des ARN épissés dans le noyau et donnant naissance aux Pioneer Translation Products (PTPs) a été décrite. Ces derniers ont été montrés comme source de peptides pour la voie de présentation des antigènes par le CMH-I. Récemment, nous avons montré que les antigènes dérivés des PTPs et présentés par les tumeurs sont capables d’entrainer une réponse lymphocytaire T cytotoxique in vivo et de contrôler la croissance tumorale. Lors de ma thèse, nous avons identifié la molécule inhibitrice de l’épissage isoginkgetin comme modulateur positif de cette présentation dans les cellules cancéreuses. De plus, nous avons observé qu’un de ses dérivées, l’IP2, qui est soluble dans l’eau et moins toxique que l’isoginkgetin, est de même capable d’augmenter la présentation des antigènes dérivés des PTPs dans les tumeurs in vitro, ainsi que de réduire la croissance tumorale in vivo de manière dépendante de la réponse immunitaire. Ainsi, le composé IP2 se révèle être un immunomodulateur de la réponse anti-tumorale efficace et prometteur pour le développement de nouvelles stratégies thérapeutiques. / Anti-tumoral therapeutic vaccines rely on the activation of the adaptative immune system and are based on the recognition of tumor antigens (TA) by specific helper and cytotoxic T lymphocytes (CTL). Their efficacy requires a careful selection of the targeted antigens as well as an unaltered MHC class I (MHC-I) antigenic presentation in tumors. While the focus was first put on exome-derived TA, evidences highlighted the ones derived from alternative translations as having a high potential as T-cells targets. These can be derived from translation of allegedly non coding sequences, initiated at alternative codons or performed in non-canonical open reading frames. Such an alternative translation occurring from pre-spliced mRNAs in the nucleus has been described as giving rise to the Pioneer Translation Products (PTPs), which constitute a source of polypeptides for the MHC-I pathway. Recently, we showed that PTPs-derived antigens presented by tumors are able to elicit a CTL response in vivo that controls tumor growth. Here, we identified one positive modulator of PTPs-derived antigenic presentation in cancer cells: the splicing inhibitor isoginkgetin. Then, we provided one of its derivatives, the IP2, which is water soluble and less toxic than the isoginkgetin, and showed that IP2 treatment increases PTPs-derived antigenic presentation of cancer cells in vitro and reduces tumor growth in vivo in an immune-dependent manner. Hence we describe here the IP2 as a new efficient immunomodulator of the antitumor response, promising for the development of innovative therapeutic strategies.

This theses traces the history of Cleburne in Johnson County, Texas through its founding during reconstruction through the early 1900s.

Dans la deuxième partie du XIXe siècle, les femmes qui osent écrire et publier sont encore très peu nombreuses. Face à une société qui les rejette ou qui les traite de bas bleus, elles sont à la recherche de solutions et celles qu’elles trouvent sont soit se cacher sous des apparences d‘hommes et publier sous pseudonyme, soit par contre, approfondir le féminin et écrire une littérature du moi : journal, autobiographie, roman épistolaire.Margareta Miller-Verghy (1865-1953), une écrivaine ignorée par les histoires littéraires, qui est pourtant parmi les premières écrivaines francophones roumaines, commence sa carrière littéraire en publiant sous pseudonyme. Ses romans, dont le dernier Blandina, qui paraît à titre posthume et en traduction roumaine, témoignent de cette littérature à forte dimension autobiographique. Son destin traverse deux siècles et peut être considéré comme représentatif du chemin que la femme-écrivain parcourt à partir de l’époque du mépris et de la méfiance du XIXe siècle, jusqu’à la pleine acceptation, au XXe siècle.Margareta Miller-Verghy naît à Jassy, Roumanie, mais passe son enfance et plus tard sa jeunesse à Genève, dans un milieu non seulement francophone, mais aussi multilingue. Ainsi s’explique son penchant pour les langues et son talent de traductrice qu‘elle exerce dans un premier temps en traduisant en français l’œuvre de Mihail Eminescu, le plus grand poète roumain. Après une licence en Sciences Sociales, obtenue toujours à Genève, elle devient directrice de l’Asile Elena Doamna, à Bucarest, et en cette qualité elle publie des ouvrages à contenu didactique, dont une méthode d’apprentissage du français, qui est parmi les premières de ce genre. Sa carrière d’écrivaine commence en 1883 avec une nouvelle parue sous le pseudonyme Marmil et continue par trois romans, le premier, Theano, paru en Roumanie et en France en 1919 et respectivement en 1921, le deuxième Cealaltă lumină (L’Autre Lumière), en 1944, un témoignage de l’accident à la suite duquel elle a perdu sa vue et le dernier Blandina (1980), qui est en fait le premier de ce cycle autobiographique. En dehors de cette activité dans le champ de la littérature, elle milite pour la littérature féminine, en publiant une anthologie intitulée Evoluţia scrisului feminin în România(Évolution de l’écrit féminin en Roumanie), s’intéressée aux arts, dirige pour une vingtaine d’année une institution qui organisait des projets culturels, La Maison d’Art, et exerce une importante activité charitable, surtout pendant la première guerre mondiale.La biographie de cette femme-écrivain, accompagnée par l’édition critique de son roman le plus connu constituent l’objet de la thèse que nous avons créée, mais pour que son œuvre et son activité si diverse et si complexe soient connues et appréciées par les générations futures, la recherche très laborieuse que nous avons réalisée dans les archives doit être élargie par un travail d’édition et de réédition. Continuer cette étude par une monographie, par une nouvelle édition du roman Blandine, par une édition d’œuvres nous semble un devoir pour les années à venir. / In the second half of the nineteenth century, women who dare to write and publish are still very few. Faced with a society that rejects them or treats them as blue bottoms, they are looking for solutions and those they find are either to hide under the appearance of men and publish under pseudonym, to be against, deepen the feminine and write a literature of the self: journal, autobiography, novel letter writer. Margareta Miller-Verghy (1865-1953), a writer ignored by literary histories, who is among the first French-speaking Romanian writers, begins her literary career publishing under pseudonym. Her novels, including the last one, "Blandina", appear posthumous and in Romanian translation testify to this literature with a strong autobiographical dimension. Her destiny goes back two centuries and can be considered representative for the path that the female writers travel from the time of contempt and mistrust of the nineteenth century to the full acceptance in the twentieth century.Margareta Miller-Verghy was born in Jassy, Romania, but spent her childhood and later her youth in Geneva, not only in a French environment, but also in a multilingual one. This explains her penchant for foreign languages and her talent as a translator, which she makes use of when translating into French the work of Mihail Eminescu, the greatest Romanian poet. After a bachelor's degree in Social Sciences, while still in Geneva, she became director of the Elena Doamna Asylum in Bucharest and in this quality she published books with didactic content, including a method of learning French, which is among the premieres of this kind. Her writing career began in 1883 with a short story published under the pseudonym Marmil and continued with three novels, the first, Theano, published in Romania and France in 1919 and respectively in 1921, the second "Cealaltă lumină" ("The Other Light"), in 1944, a testimony of the accident in which she lost her eyesight, and the last "Blandina" (1980), which is actually the first of this autobiographical cycle. Apart from this activity in the field of literature, she advocates for women's literature, publishing an anthology entitled "Evoluția scrisului feminin în România" ("Evolution of the female writing in Romania"). She is interested in arts, directs for twenty years an institution that organizes cultural projects, The House of Art, and has a significant charitable activity, especially during the First World War.In order for her work, which is so diverse and so complex, to be known and appreciated by future generations, the very laborious research we have carried out in the archives must be expanded by editing and re-editing. To continue this study with a monography, with a new edition of the novel "Blandine", with an edition of gathered works seems to us a duty for the years to come.

Este trabalho procura avaliar a relação existente entre a expansão espacial do povoamento ocorrida no Brasil na primeira metade do século XX e o processo de formação territorial do país, trazendo a lume a importância das relações sociais que ocorriam na fronteira para a composição de uma explicação geográfica sobre o fenômeno do pioneirismo. Tomando como ponto de partida a análise da noção de frente pioneira explicitada na obra do geógrafo francês Pierre Monbeig entre as décadas de 1930 e 1950, busca-se apontar de que maneira a descrição explicativa das áreas de movimentação de fronteiras dinamizadas pela expansão espacial da colonização, que impulsionou a fundação de cidades, o desmatamento de florestas e a abertura de campos de cultivo e pastos, comporta uma análise sobre o processo de construção dos sistemas de engenharia que conseguiram consolidar nexos de solidariedade entre distintos lugares, garantindo maior fluidez e integração a um território que modificava sua organização espacial para se adequar às novas necessidades surgidas com a expansão do capitalismo no Brasil. Figura de destaque no ensino e pesquisa em geografia desenvolvidos no Brasil nas décadas de 1930 e 1940, especialmente na Faculdade de Filosofia, Ciências e Letras da Universidade de São Paulo, onde foi um dos fundadores do curso de Geografia e História, Pierre Monbeig é um dos protagonistas da institucionalização acadêmica do campo geográfico no país, influenciando diretamente a formação da primeira geração de geógrafos brasileiros saídos dos bancos universitários. Assim sendo, este trabalho colocou como objetivo específico rastrear a influência do enquadramento oferecido por Monbeig em seus trabalhos sobre o pioneirismo nas pesquisas de autores como Ary França, José Ribeiro de Araújo Filho, Renato da Silveira Mendes, Nice Lecocq Müller e Pasquale Petrone, discípulos do francês que assumiram uma posição institucional de relevo no cenário da geografia brasileira a partir da década de 1950, tornando-se os continuadores do curso de Geografia da FFCL/USP. / The aim of this work is to analyze the relation between the spatial expansion of Brazilian settlement occurred in the first half of the twentieth century and the process of territorial formation, with a focus on the role of the frontiers social relations in the construction of a geographic approach for the pioneering phenomena. Based upon the analysis of the pioneer fringe as it is expounded in the work of French geographer Pierre Monbeig between the 1930s and the 1950s, we intend to point out in what ways the descriptive explanation of the moving frontier, which impelled, for its turn, the foundation of cities, the deforestation and the formation of agriculture fields and pastures, reveals an interpretation about the construction of engineering systems planned to consolidate spatial relations among different places in the Brazilian territory, ensuring the territorial integration necessary for the expansion of capitalism in Brazil. Pierre Monbeig is a distinguish figure of the Brazilian geographic movement, fulfilling an important role in the institutionalization of the geographic scientific field as one of the greatest scholar figures that ever worked in this country. The analysis of the influence brought together with his activities as a teacher and researcher developed in the Department of Geography of the São Paulo University during the 1930s and the 1940s, which he helped to organize and establish, can be taken in consideration as a demonstration of the reach of his works for the generation of students that came after him in the University. Thus, this work seeks to examine the influence of the explicative frame held in Monbeigs studies of the pioneer fringe on the research developed by authors like Ary França, José Ribeiro de Araújo Filho, Renato da Silveira Mendes, Nice Lecocq Müller and Pasquale Petrone, all of them future teachers in the same Department of Geography in São Paulo.

Minerva Teichert (1888-1976) was a twentieth-century American artist, who spent most of her life residing in remote towns in the West, earnestly balancing the demands of family and ranching, and painting scenes of her beloved Western frontier. Her steady and significant production of art is remarkable for any artist, and particularly compelling when one considers her time constraints, inaccessibility of art supplies, distance from other artists and art centers, and lack of public attention. The success of women artists during the first half of the twentieth-century was dependent not only upon their artistic aptitude, but also upon external forces, such as family, friends, and mentors. As an artist during this era, Teichert benefitted especially from the circles of women who surrounded her, offering sympathy, encouragement, assistance, a ready network of support, and who enabled her to pursue her passion, which she succinctly described, “I must paint.” This thesis employs a methodological framework informed by feminist, collective conscience, and social network theories in order to elucidate an artist's vision that transcends feminist viewpoints and western heroic individualism. The reality of female networks in Teichert's life translates not only to the certainty of women within a Western mythology dominated by men but also to a powerful counter-narrative where collaboration and community are essential to the success of settlements in the American West. Here Teichert introduces an altogether different vision and story. In her pioneer paintings, composed during the 1930s and 1940s, one sees a reflection of her own life, and that of her pioneer ancestors, which emphasizes the feminine, the importance of collaboration, and the centrality of community.

<p>The aim of the thesis is to cast light on the earliest settlement of northern Sweden. The starting point is lithic artifacts, which have been studied from a technological as well as a more conventional typological perspective (Papers I, II, and IV). Paper III deals primarily with geological and palaeoecological methods and my contribution is mainly confined to the lithic artifacts. The main research objectives are concerned with early postglacial colonization and cultural affiliation mirrored through technological traditions. Another “main thread” is a source-critical discussion regarding dating problems, and the chronological integrity of find contexts. The chronological position of artifact types in the North Swedish Mesolithic is another related problem being discussed.</p><p>The geographical area under investigation comprises northern Sweden sensu largo: Norrland plus the provinces of Värmland and Dalarna. The time period studied is the Mesolithic, with an emphasis on the earliest part, ca. 8500–7500 BP.</p><p>Paper I discusses the Mesolithic in the province of Värmland. There are traits indicating both an affiliation with the Lihult/Nøstvet sphere (for example, Lihult axes and saws/knives of sandstone) as well as other features more common in an eastern/northern context (quartz use, bipolar reduction, and, at least for the final Mesolithic and Neolithic, slate artifacts).</p><p>Paper II aims at elucidating microblade technology in northern Sweden as regards chronological position and cultural context. It was found that microblade production from handle cores (also called wedge-shaped cores) was introduced at about the same time in northern Sweden as in other areas of Scandinavia where these artifacts occur, ca. 8000–7500 BP. The handle core tradition continued until ca. 5500/5000 BP.</p><p>Paper III deals with lake-tilting caused by non-uniform glacio-isostatic uplift. This phenomenon has been used to identify potential areas of Mesolithic occupation in the Arjeplog area, Lapland. Surveys and excavations within the research project "Man, Fire, and Landscape", have significantly increased the number of Mesolithic sites in the area. The investigations have resulted in the discovery of the oldest firmly dated archaeological site in northern Sweden, Dumpokjauratj, in Arjeplog parish, Lapland, with a maximum date of 8630 ± 85 BP.</p><p>Paper IV discusses the pioneering phase of occupation in northern Sweden, in the light of the above-mentioned site of Dumpokjauratj and a site at Garaselet in northern Västerbotten. These are further compared with contemporary sites in surrounding areas of Fennoscandia. The majority of the assemblages are dominated by platform reduction, even if bipolar reduction also occurs at the earliest sites. Slate artifacts found at Dumpokjauratj suggest connections with the Finnish Mesolithic, which is the only cultural context in our region with documented slate use at this early point in time. But there are also traits that do not specifically point towards Finland, e.g. frequent use of fine-grained flint-like materials and porphyry, and (at Dumpokjauratj) a lanceolate microlith made of a microblade of this fine-grained igneous rock. The latter suggests associations with the Scandinavian Mesolithic in general.</p><p>In any event, the early dates from Dumpokjauratj show that interior Lapland was occupied soon after deglaciation, probably within a few hundred years.</p>

The aim of the thesis is to cast light on the earliest settlement of northern Sweden. The starting point is lithic artifacts, which have been studied from a technological as well as a more conventional typological perspective (Papers I, II, and IV). Paper III deals primarily with geological and palaeoecological methods and my contribution is mainly confined to the lithic artifacts. The main research objectives are concerned with early postglacial colonization and cultural affiliation mirrored through technological traditions. Another “main thread” is a source-critical discussion regarding dating problems, and the chronological integrity of find contexts. The chronological position of artifact types in the North Swedish Mesolithic is another related problem being discussed. The geographical area under investigation comprises northern Sweden sensu largo: Norrland plus the provinces of Värmland and Dalarna. The time period studied is the Mesolithic, with an emphasis on the earliest part, ca. 8500–7500 BP. Paper I discusses the Mesolithic in the province of Värmland. There are traits indicating both an affiliation with the Lihult/Nøstvet sphere (for example, Lihult axes and saws/knives of sandstone) as well as other features more common in an eastern/northern context (quartz use, bipolar reduction, and, at least for the final Mesolithic and Neolithic, slate artifacts). Paper II aims at elucidating microblade technology in northern Sweden as regards chronological position and cultural context. It was found that microblade production from handle cores (also called wedge-shaped cores) was introduced at about the same time in northern Sweden as in other areas of Scandinavia where these artifacts occur, ca. 8000–7500 BP. The handle core tradition continued until ca. 5500/5000 BP. Paper III deals with lake-tilting caused by non-uniform glacio-isostatic uplift. This phenomenon has been used to identify potential areas of Mesolithic occupation in the Arjeplog area, Lapland. Surveys and excavations within the research project "Man, Fire, and Landscape", have significantly increased the number of Mesolithic sites in the area. The investigations have resulted in the discovery of the oldest firmly dated archaeological site in northern Sweden, Dumpokjauratj, in Arjeplog parish, Lapland, with a maximum date of 8630 ± 85 BP. Paper IV discusses the pioneering phase of occupation in northern Sweden, in the light of the above-mentioned site of Dumpokjauratj and a site at Garaselet in northern Västerbotten. These are further compared with contemporary sites in surrounding areas of Fennoscandia. The majority of the assemblages are dominated by platform reduction, even if bipolar reduction also occurs at the earliest sites. Slate artifacts found at Dumpokjauratj suggest connections with the Finnish Mesolithic, which is the only cultural context in our region with documented slate use at this early point in time. But there are also traits that do not specifically point towards Finland, e.g. frequent use of fine-grained flint-like materials and porphyry, and (at Dumpokjauratj) a lanceolate microlith made of a microblade of this fine-grained igneous rock. The latter suggests associations with the Scandinavian Mesolithic in general. In any event, the early dates from Dumpokjauratj show that interior Lapland was occupied soon after deglaciation, probably within a few hundred years.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 201-213).

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 711-770). Also available on the Internet.