Durante muitas décadas, extensas áreas de florestas nativas têm sido sistematicamente destruídas no Brasil, muitas delas dando lugar a plantações florestais para fins industriais. A adequação à legislação ambiental recente, no que se refere à manutenção de áreas de preservação permanente e de reservas legais, passou a gerar a necessidade de reversão de áreas ocupadas com plantios comerciais para florestas nativas. Este trabalho teve como objetivo estudar a efetividade de técnicas para acelerar a regeneração natural da vegetação nativa em talhões de Eucalyptus saligna abandonados. O estudo foi realizado em áreas pertencentes à Suzano Papel e Celulose, onde foi criado o Parque das Neblinas, município de Bertioga, SP. A área experimental foi instalada em um talhão de terceira rotação com 45 ha, manejado anteriormente em ciclos de corte de sete anos. O experimento foi em blocos ao acaso com seis tratamentos e quatro repetições: T1=controle, T2-T5=redução de 25, 50, 75 e 100% da área basal, respectivamente, através de envenenamento com glyphosate; T6=corte raso. Cada parcela apresentou 20 m x 40 m. Inicialmente foi realizado um inventário da população de Eucalyptus saligna, bem como o levantamento fitossociológico de toda a regeneração natural existente acima de 1,30 m de altura. Foram mensurados 1.417 indivíduos de Eucalyptus saligna, com densidade absoluta de 738,02 ind/ha e área basal de 22,68 m²/ha. O método utilizado para morte em pé dos eucalitpos se mostrou eficiente. No conjunto dos 5.863 indivíduos amostrados da vegetação nativa, foram identificadas 135 espécies, pertencentes a 77 gêneros e a 39 famílias. A densidade total estimada foi de 1.035,41 indivíduos/ha e a área basal de 6,39 m²/ha, para a classe de indivíduos da regeneração natural com DAP 5 cm e de 3.864,58 indivíduos/ha e área basal de 3,25 m²/ ha, para regeneração natural com DAP < 5 cm e maior que 1,30 m de altura. Não houve efeito significativo dos tratamentos a 5% de probabilidade para as variáveis estruturais. Entretanto, o estudo da riqueza de espécies corrigida (correção feita usando-se o índice de Fisher) para a regeneração com DAP 5 cm revelou um decréscimo nas parcelas testemunha entre as fases inicial e final e um aumento deste índice para os demais tratamentos. Além disso, a variação percentual do índice de diversidade de Shannon (H) entre as épocas inicial e final apresentou diferenças significativas entre tratamentos e blocos, sendo que o T3 propiciou significativamente os maiores aumentos da diversidade de espécies (H). Embora não tenha havido efeito do tratamento na área basal da regeneração natural, houve uma correlação linear negativa desta variável com a área basal do eucalipto. O resultado indica uma tendência de aumento de área basal da vegetação nativa com DAP 5 cm à medida que se reduz a área basal do eucalipto. As análises mostraram que o T3 (redução de 50% da área basal do eucalipto através de morte em pé das árvores) propiciou os melhores resultados para densidade, área basal e riqueza de espécies para as duas classes de regeneração natural, após 40 meses. / For decades, large areas of native forests have been and still systematically destroyed in Brazil, many of them leading to forest plantations stands for industrial purposes. The adequacy to the recent environmental legislation regarding the maintenance of permanent preservation areas and legal reserves required reversing the areas occupied with commercial plantations into native forests. This study aimed at verifying the effect of techniques to accelerate the natural regeneration of native vegetation in abandoned production stands of Eucalyptus saligna. The study was conducted in areas belonging to the Suzano Papel e Celulose, at Parque das Neblinas, Bertioga, SP. The experiment was set up in a commercial Eucalyptus saligna stand with 45 ha, third rotation, previously managed in seven-year cutting cycles. The experimental design was in randomized blocks with six treatments and four replications. The treatments were: T1= control; T2-T5= reduction of 25, 50, 75 and 100% of basal area, respectively, through girdling and poisoning and T6= clearcut. Each plot had 20 x 40 meters. An inventory on the Eucalyptus saligna population was performed, as well as a phytosociological survey of the entire natural regeneration over 1.3 m in height 1,417 individuals of Eucalyptus saligna were measured and showed an absolute density of 738.02 ind/ha and 22.68 m²/ha basal area. As to the treatment applied (T2-T5) to the eucalyptus individuals, the method was proved efficient. We sampled 5,863 individuals of native vegetation belonging to 135 species of 77 genera and 39 families. The total density estimated was 1,035.41 individuals/ha and the basal area was 6.39 m²/ha for the DBH 5 cm class and 3,864.58 individuals/ha and basal area of 3.25 m²/ ha for the natural regeneration with DBH < 5 cm. There was no significant effect of the treatments at a 5% probability level for the variables studied. Although, the richness analysis corrected (correction through the Fishers index) for the DBH 5 cm class showed decrease in the control plots between the initial and final phases, and an increase in the richness of the remaining treatments. In addition, the percent variation of the Shannons diversity index between the initial and final times had a significant effect for treatments and blocks, being the T3 showed significant increase in species diversity (H). Although no significant effect was observed for the basal area, a negative linear correlation of this variable with the eucalypt basal area was observed. The result points to a trend of increase in the basal area of the native vegetation with DBH > 5 cm as the eucalypt basal area is reduced. T3 (50 % reduction of the eucalypt basal area by poisoning) showed best results for density, basal area and species richness of for both natural regeneration classes after 40 months.

O projeto "Avaliação de Aspectos da Dinâmica de Florestas Restauradas, com Diferentes Idades", teve como objetivo geral identificar indicadores que possam ser utilizados na avaliação e monitoramento de áreas restauradas, através do restabelecimento da resiliência nessas áreas. Este trabalho foi desenvolvido em três áreas restauradas: Usina Açucareira Ester, no município de Cosmópolis-SP, sendo 9 ha submetidos ao plantio de espécies nativas e exóticas entre 1955 e 1960 (@ 46 anos); Área Experimental da Plantec, no município de Iracemápolis-SP, com 1ha de área plantada com espécies nativas e exóticas, em 1992 (@ 9 anos); área da Dedini S/A Agroindústria, no município de Santa Cruz das Palmeiras-SP, com 1ha submetido ao plantio de espécies nativas entre 1995 e 1997 (@ 6 anos). Estas áreas se diferenciam entre si pelo tempo de implantação, pelo número de espécies plantadas e pela metodologia de restauração utilizada. Em cada área foram alocadas 10 parcelas amostrais de 10x20m, com 6 sub-parcelas de 0.5x0.5m, com três repetições para cada tratamento analisado. Para avaliar a chuva de sementes, instalou-se 3 coletores de 0.5x 0.5m por parcela amostral (30 coletores por área), com coletas mensais. Para avaliação do banco de sementes, realizaram-se 2 coletas de solo e de folhedo (abr/01 e jun/01), por unidade O projeto “Avaliação de Aspectos da Dinâmica de Florestas Restauradas, com Diferentes Idades”, teve como objetivo geral identificar indicadores que possam ser utilizados na avaliação e monitoramento de áreas restauradas, através do restabelecimento da resiliência nessas áreas. Este trabalho foi desenvolvido em três áreas restauradas: Usina Açucareira Ester, no município de Cosmópolis-SP, sendo 9 ha submetidos ao plantio de espécies nativas e exóticas entre 1955 e 1960 (@ 46 anos); Área Experimental da Plantec, no município de Iracemápolis-SP, com 1ha de área plantada com espécies nativas e exóticas, em 1992 (@ 9 anos); área da Dedini S/A Agroindústria, no município de Santa Cruz das Palmeiras-SP, com 1ha submetido ao plantio de espécies nativas entre 1995 e 1997 (@ 6 anos). Estas áreas se diferenciam entre si pelo tempo de implantação, pelo número de espécies plantadas e pela metodologia de restauração utilizada. Em cada área foram alocadas 10 parcelas amostrais de 10x20m, com 6 sub-parcelas de 0.5x0.5m, com três repetições para cada tratamento analisado. Para avaliar a chuva de sementes, instalou-se 3 coletores de 0.5x 0.5m por parcela amostral (30 coletores por área), com coletas mensais. Para avaliação do banco de sementes, realizaram-se 2 coletas de solo e de folhedo (abr/01 e jun/01), por unidadeO projeto "Avaliação de Aspectos da Dinâmica de Florestas Restauradas, com Diferentes Idades", teve como objetivo geral identificar indicadores que possam ser utilizados na avaliação e monitoramento de áreas restauradas, através do restabelecimento da resiliência nessas áreas. Este trabalho foi desenvolvido em três áreas restauradas: Usina Açucareira Ester, no município de Cosmópolis-SP, sendo 9 ha submetidos ao plantio de espécies nativas e exóticas entre 1955 e 1960 (@ 46 anos); Área Experimental da Plantec, no município de Iracemápolis-SP, com 1ha de área plantada com espécies nativas e exóticas, em 1992 (@ 9 anos); área da Dedini S/A Agroindústria, no município de Santa Cruz das Palmeiras-SP, com 1ha submetido ao plantio de espécies nativas entre 1995 e 1997 (@ 6 anos). Estas áreas se diferenciam entre si pelo tempo de implantação, pelo número de espécies plantadas e pela metodologia de restauração utilizada. Em cada área foram alocadas 10 parcelas amostrais de 10x20m, com 6 sub-parcelas de 0.5x0.5m, com três repetições para cada tratamento analisado. Para avaliar a chuva de sementes, instalou-se 3 coletores de 0.5x 0.5m por parcela amostral (30 coletores por área), com coletas mensais. Para avaliação do banco de sementes, realizaram-se 2 coletas de solo e de folhedo (abr/01 e jun/01), por unidadeO projeto “Avaliação de Aspectos da Dinâmica de Florestas Restauradas, com Diferentes Idades”, teve como objetivo geral identificar indicadores que possam ser utilizados na avaliação e monitoramento de áreas restauradas, através do restabelecimento da resiliência nessas áreas. Este trabalho foi desenvolvido em três áreas restauradas: Usina Açucareira Ester, no município de Cosmópolis-SP, sendo 9 ha submetidos ao plantio de espécies nativas e exóticas entre 1955 e 1960 (@ 46 anos); Área Experimental da Plantec, no município de Iracemápolis-SP, com 1ha de área plantada com espécies nativas e exóticas, em 1992 (@ 9 anos); área da Dedini S/A Agroindústria, no município de Santa Cruz das Palmeiras-SP, com 1ha submetido ao plantio de espécies nativas entre 1995 e 1997 (@ 6 anos). Estas áreas se diferenciam entre si pelo tempo de implantação, pelo número de espécies plantadas e pela metodologia de restauração utilizada. Em cada área foram alocadas 10 parcelas amostrais de 10x20m, com 6 sub-parcelas de 0.5x0.5m, com três repetições para cada tratamento analisado. Para avaliar a chuva de sementes, instalou-se 3 coletores de 0.5x 0.5m por parcela amostral (30 coletores por área), com coletas mensais. Para avaliação do banco de sementes, realizaram-se 2 coletas de solo e de folhedo (abr/01 e jun/01), por unidade amostral (0.25x0.25m), na profundidade de 0.05m. Para avaliação dos indivíduos jovens regenerantes, foram amostrados todos os indivíduos entre 0.30-1.30m de altura, em 2 sub-parcelas (1x1m) por parcela amostral (mai/01 e nov/01). Foram realizados cálculos de freqüência e de densidade absoluta através do teste do logaritmo da verossimilhança (teste G). As análises de variância (teste F) foram realizadas para verificar o crescimento em altura dos indivíduos amostrados nas diferentes avaliações. Quando diferenças significativas foram encontradas, aplicou-se o teste de Tukey a 5% de probabilidade para determinar entre quais grupos as médias diferiam significativamente. O fluxo de propágulo mensurado nas áreas em estudo, durante o período de oito meses, apresentou diferença altamente significativa (P = 0,001), ou seja a chuva de sementes apresentou-se de forma heterogênea, sendo que as espécies arbóreas predominaram sobre as herbáceas, lianas e arbustivas. A investigação do banco de sementes nas três áreas revelou variações altamente significativas (P = 0,001) na densidade de sementes nas duas avaliações (jan/01 e jun/01). Constatou-se que o número de espécies herbáceas que germinaram no banco de sementes nas três áreas tendeu a diminuir e as arbóreas a aumentar com a idade da restauração. Os indivíduos jovens amostrados nas áreas em estudo são compostos predominantemente por espécies arbóreas. A proporção de indivíduos jovens presentes nas avaliações apresentou diferença significativa (P = 0,32), entre as avaliações, isto é, houve um recrutamento de novos indivíduos na segunda avaliação. Os resultados obtidos neste estudo nos leva a concluir que recuperar uma área degradada não depende apenas do plantio de espécies nativas mas depende: i) do histórico do uso da terra a ser restaurada, ii) do grau de isolamento e iii) do monitoramento e da avaliação dos projetos de restauração, permitindo dessa forma, definir intervenções de manejo que garantam o sucesso do empreendimento em termos de perpetuação das áreas restauradas. / The project "Evaluation of aspects of the dynamics in restored forests, with different ages" had as main aim to define indicators that can be used in the evaluation and monitoring of restored areas, through the reestablishment of the resilience in those areas. This task was performed in three restored areas: Ester Sugar Mill, in Cosmopolis – SP, having 9ha been submitted to native and exotic species planting between 1955 and 1960 (@ 46 years); Experimental Area at Plantec, in Iracemapolis – SP, with 1ha of planted area, including native and exotic species, in 1992 (@ 9 years); Dedini Agro industry Area, in Santa Cruz das Palmeiras – SP, with 1ha submitted to native species planting between 1995 and 1997 (@ 6 years). These areas differ among themselves from implementing time, number of planted species and restoration methods. In each area, 10 samples of 10x20 m were selected, with 6 sub samples of 0.5x0.5 m, and three repetitions for each treatment analyzed. For evaluating the seeds rain, 3 collectors of 0.5x0.5 m were installed for each sample (30 collectors per area), with monthly samplings. For evaluating the seeds bank, 2 samplings of soil and foliage were performed (April/01 and June/01) per sample (0.25x0.25 m), at 0.05 m depth. For evaluating the regenerating young individuals, all the individuals between 0.30 – 1.30 m height were sampled, in 2 sub samples (1x1 m) per sample (May/01 and November/01). Frequency and absolute density calculations were performed through the logarithm of truthfulness test (test G). The variation analysis (Test F) were performed for verifying the height growth of the individuals sampled in different evaluations. When significant differences were found, the probability Tukey test at 5% was applied for determining between which groups the averages differed significantly. The propagation flow measured in the areas, during an 8- month period, presented highly significant differences (P = 0.001), i.e., the seeds rain occurred heterogeneously, when the arboreal species overwhelmed the herbaceous, lianas and bushy ones. The investigation of the seeds bank on the three areas revealed highly significant variations (P = 0.001) in the seeds density in both evaluations (January and June/01). It has been noted that the number of herbaceous species germinated on the seeds banks on the three areas tended to diminish, and the arboreal, to increase along the restoration phase. The young individuals shown on the study areas are mainly arboreal species. The young individuals proportion present at the evaluations presented significant variations (P = 0.32), between the evaluations, i.e., there was a recruiting of new individuals on the second evaluation. The results on this study lead us to conclude that for recovering a degraded area does not only depend on the planting of native species but depends on i) the studying of the land use, ii) the isolation grade and iii) the monitoring and evaluation of the restoration projects, thus allowing the definition of the intervening handlings that can guarantee the success of the undertaking in terms of the restored areas perpetuation.

Este trabalho tem por finalidade o estudo da permeabilidade da madeira, com ênfase nas espécies de florestas plantadas do gênero de Pinus elliotti, Eucalyptus grandis e Eucalyptus citriodora. Com a sua determinação, avalia-se o quanto uma dada espécie de madeira é permeável a preservativos (tratamentos químicos) e o quanto ela é permeável a aplicação de adesivos estruturais (confecção de peças estruturais em Madeira Laminada Colada MLC). A avaliação da permeabilidade é um fator fundamental para definição do tratamento preservativo da madeira. Para isto foi projetado e construído um equipamento alternativo, para uso laboratorial, visando determinar a permeabilidade e analisar qual espécie dentre as estudadas seriam mais permeáveis a fluidos líquidos e gasosos em madeiras brasileiras de florestas plantadas. O equipamento construído permite a determinação do escoamento de fluidos em corpos-de-prova cilíndricos de madeira, em todas as suas direções ortogonais. Os resultados obtidos mostram que o equipamento é adequado para a determinação da permeabilidade a líquido ou gás em madeiras, onde na direção longitudinal, o alburno E. grandis é a parte do lenho mais permeável a líquido e gás, seguido do alburno do E. citriodora, Pinus elliottii e cerne do E. grandis. Com exceção do Pinus elliottii na direção transversal, as demais espécies não apresentaram vazão nesta direção. / This work aims to study permeability of wood especially in reforestation species like Pinus elliotti, Eucalyptus grandis and Eucalyptus citriodora in order to evaluate how much a given wood species is permeable to preservatives (chemical treatments) and how much it is permeable to application of structural adhesives (making of structural pieces in Glued Laminated - MLC). Evaluation of permeability is a fundamental factor when defining the preservative treatment to able applied in the wood, so an alternative equipment has been especially designed and built aiming to determine its permeability and analyze which one of the studied Brazilian reforestation species would be more permeable to liquid and gaseous fluids. This laboratorial equipment has allowed determination of fluid drainage in cylindrical samples of wood in all of its orthogonal directions. Obtained results have shows that it is appropriate for determining liquid or air permeability of wood where, in longitudinal direction, E. grandis sapwood has been the most permeable part, followed by E. citriodora sapwood, Pinus elliottii and E. grandis heartwood. None of the species has presented any flow in traverse direction, except Pinus elliottii.

The “2015 proceedings” document the contributions of the third and final annual Summer-School Workshop of the “Scientific Cooperation Network on Climate Change Adaptation”, a project within the DAAD program “Welcome to Africa”. The workshop took place on 17-31 May, 2015 at Tharandt campus of the Technische Universität Dresden and at selected locations in the region.:Climate Change Adaptation and Mitigation 1 Methodological Fundamentals of Socio-Economic Climate Change Adaptation Research at the Institute of International Forestry and Forest Products, TU Dresden 2 Climate Change Adaptation in Saxony 4 Historical Path of Forestry and the Role of ‘Ujamaa’ Ideology to Today’s Policy of Community Forest Management in Tanzania 19 Contribution of the National Adaptation Plan of Action Project to Sustainable Livelihoods in North Kordofan State, Sudan 31 Local People’s Perception of Climate Variability Including Their Mitigation and Adaptation Strategies in Mountainous Areas of Uganda 47 Role of Indigenous Knowledge in Traditional Farming System Management under Changing Climate, Sudan 54 Quarterly Climate Change Preparedness Workshop in Arsi Negelle, Ethiopia 63 Impact of Farmer Field Schools in Diffusion of Information about Climate Change in South Kordofan State, Sudan 74 Effects of Climate Change on Traditional Rain-fed Agriculture in Sheikan Locality, North Kordofan State, Sudan 81 Can Rain Water Harvesting Mitigate Flooding Associated with Climate Change in Urban Areas? A Case Study of Jinja Municipality, Uganda 91 Agroforestry, Reforestation, and Climate Change 97 Agroforestry in Reducing Emissions from Deforestation and Forest Degradation (REDD+): Africa, Where Are You? 98 Carbon Sequestration and Greenhouse Gas Emissions in Agroforestry: Summary of Global Data and Implications for Africa 113 Propagation Techniques for Ethiopian Highland Bamboo Yushania alpina in Amhara Region, Banja Districts, North-Western Ethiopia 121 The Performance of GAPAs on Enhancing the Production and Marketing of Gum Arabic Production in West and North Kordofan States, Sudan 131 CHAnces IN Sustainability – Promoting Product Chains of Natural Products in Eastern Africa 132 Biodiversity Conversation and Bioenergy 135 Land Use, Land Cover and Climate Change Impacts on the Bird Community in and around Lake Zeway, Ethiopia 136 African Baobab: Urgent Need for Assessments and Management Approaches for Sustainable Development in Sudan 137 Ecotourism as Alternative Mean of Biodiversity Conservation and Livelihood Improvement of the Local Community 145 The Role of Wood Fuel in Climate Change: A Case of Urban and Rural Areas in Uganda 159 Scientific Cooperation Network on Climate Change Adaptation 169 Network Contact Persons 169

During the last century coal extraction has degraded ecosystems in Appalachia, converting forested land into other cover types that have a diminished capacity to naturally progress to later stages of succession. This projects objective was to examine two options for land-use that can assist in returning the reclaimed surface mines to forested cover types, with increased ecosystem services, and a potential for economic gain. This project examined a biomass plantation and an American chestnut trial. In the biomass trial, greatest heights for American sycamore (12.3 m) and black locust (8.0 m) were found in the fertilizer plots. Mean individual tree biomass for American sycamore and black locust was 6.4 Kg and 5.3 Kg, respectively; no significant differences were found among treatments. In the American chestnut trial, experimental wide survival was 47.2% in 2009, dropping to 24.74% in 2017. No significant differences were found by genotype, stock type, or the interaction in 2017. Use of mined land for woody biomass plantations and locales for chestnut restoration shows potential if proper management techniques are followed. Given the vast amounts of land disrupted by mining activities in Appalachia, approaches such as these deserve further attention and additional research.

No description available.

The origin and classification of open and mosaic ecosystems, particularly in the tropics and subtropics, have led to controversy worldwide. This has affected biodiversity conservation and, in some cases, promoted the establishment of afforestation projects based on the assumption that open and mosaic ecosystems are degraded forests. Although this initiative can have benefits in terms of carbon storage and climate mitigation if carefully planned and managed, it can also cause biodiversity loss and degradation when afforestation takes place in areas that were previously open ecosystems, or where unsuitable species are used. Madagascar, a world biodiversity hotspot, is one of the countries targeted for the implementation of afforestation projects. The Central Highlands of Madagascar, dominated by grassland matrix with forest patches, is the main region targeted. The nature and origin of the landscape are hotly debated, however, and it is not clear whether these open ecosystems are ancient or anthropogenically derived. Understanding of landscape history is therefore required to identify and conserve ancient open ecosystems, and to distinguish them from areas that have been deforested by people. This research aims to reconstruct the vegetation history and environmental change in the Central Highlands of Madagascar during the Holocene using palaeoecological methods, in order to inform appropriate conservation and management plans. We provide new records of vegetation, hydrological change, fire and herbivory activities by using a multiproxy approach, which includes fossil pollen, stable carbon isotopes, diatoms, charcoal and coprophilous spores, that allows for a comprehensive investigation into the history and drivers of vegetation change. Sediment cores were collected from two sites, Tampoketsa-Ankazobe wetland and Lake Dangovavy, located in the eastern and western slopes of the highlands, respectively. Results indicated that the surrounding area of both sites was composed of mosaic ecosystems, comprising of forest patches of variable extent in a matrix of open grassland and ericoid shrubland vegetation, at least from the Early and Mid-Holocene to ca. 1000 cal years BP, driven mainly by climate variability and fire occurrence. In Tampoketsa-Ankazobe wetland (eastern slopes), the vegetation was characterised by a mosaic of ericoid shrubland and mid-elevation forest taxa, between ca. 11 200 and 8300 cal years BP, under warm/wet period and low fire occurrence. The vegetation in the area changed to a mosaic of ericoid shrubland with more dominance of high-elevation forest from ca. 8300 to 1000 cal years BP under a drier climate and consistent low fire occurrence. The abundance of shrubs and trees during those two periods were confirmed by the dominance of C3 plants as reflected by the stable carbon isotopes results, and coincided with low herbivory activities in the TampoketsaAnkazobe site from ca. 11 200 to 1000 cal years BP. In parallel, the pollen record from Lake Dangovavy (western slopes), between ca. 6200 and 5400 cal years BP, suggests a mosaic ecosystem, dominated by more C3 montane grass, ericoid shrubland and high elevation forest patches promoted by cool/dry climate with low fire occurrence and herbivory activities. Between ca. 5400 and 4200 cal years BP, vegetation in the area was dominated by a mosaic of ericoid shrubland and mid-elevation forest under a wetter period, moderate fire occurrence, and herbivory activities. This mosaic was controlled by climate, fire refugia and herbivory feedbacks. The vegetation changed into a forest-savanna mosaic with an abundance of grassland and pioneer/fire-resistant trees between ca. 4200 and 3000 cal years BP. The period was characterised by an initial increase of local fire followed by a regional drought event. This suggests that a threshold might have been reached, with a resulting shift in vegetation composition. Between ca. 3000 and 1000 cal years BP, reoccurrence of ericoid shrubland with woodland savanna taxa was recorded in the area. The vegetation was conditioned by variation of climate from wet (until ca. 2000 cal years BP) to dry period (ca. 2000–⁠1000 cal years BP) with moderate fire occurrence and herbivory activities. In addition, stable carbon isotope results show that between ca. 6200 to 1000 cal years BP, the site was characterised by C3 plants. During the last ca.1000 cal years BP, pollen records from both sites in the Central Highlands of Madagascar showed a shift to a more open landscape dominated by grassland. Trees and shrubland in the highlands experienced a massive decrease and this correlated with an abundance of C4 plants associated with reduced diversity. The shift of vegetation during this period was likely a result of a centennial severe drought period at ca. 950 cal years BP, as recorded in the literature and confirmed by the peak in aerophilous taxa in our diatom record. The drought was followed by a dramatic increase of fire occurrence and herbivory activities in the region, as recorded in the charcoal and spore records from both sites, indicating human activities at ca. 700 and 500 cal years BP for Lake Dangovavy and Tampoketsa-Ankazobe wetland, respectively. Though the vegetation at both sites in Central Highlands of Madagascar was very dynamic until ca. 1000 cal years BP, complex interactions between climate and fire allowed the forest and ericoid elements to persist, consistent with a heterogeneous mosaic landscape. This changed from 1000 years ago with the occurrence of a regional severe drought event followed by an increase in human activities leading to an increase of grass, a decline in forest and ericoid elements. Our findings suggest that although, the eastern and western slopes in Madagascar might have different vegetation histories over time as a response to the complex climatic-fire drivers at least until ca. 1000 cal years BP, they both: a) Contained ancient open ecosystems such as grasslands and/or ericoid shrubland, and a mosaic landscape which should be considered typical of the highland region. b) Experienced a loss of forest, woodland and mosaic elements, a trend that is consistent with the anthropogenic conversion of some forests to grasslands since ca. 1000 cal years BP. Such findings have implications in terms of conservation, fire management and afforestation projects in the Central Highlands, and provide additional knowledge that contributes to the understanding of its ecological processes and history prior to human arrival on the island. Indeed: 1) Ancient grasslands and ericoid shrubland need to be identified and conserved because of their antiquity and unique biodiversity. To date, there has been some focus on ancient grasslands, but the presence of ancient heathlands has not been discussed. 2) It is important to distinguish ancient from derived grasslands and to target the latter for reforestation, using species that are typical of the remaining forest patches. 3) Fire management should be conducted at a local scale and should incorporate the landscape fire history, considering, for example, the differences between two slopes in the Central Highlands.

Hurricane Katrina had a devastating impact on bottomland hardwood forests in 2005 resulting in damage to nearly 1.2 billion cubic meters of timber. Following such a natural disaster, natural regeneration is typically not a viable option because the seed source has been destroyed on site. Therefore, an economically efficient method of artificial regeneration is considered the most appropriate technique for reforesting these damaged areas. However, few studies have evaluated comparative research that examined early survival and growth performance of various oak species and stock types in such planting settings. This project was implemented in an effort to expand upon what is already known from previous artificial regeneration attempts on Hurricane Katrina damaged lands. Bareroot, conventional containerized, and large potted EKOgrownTM seedlings of cherrybark oak (Quercus pagoda Raf.) and willow oak (Quercus phellos L.) were planted on two sites located in south Mississippi. Survival was assessed monthly and at the end of each growing season, whereas height and groundline diameter (GLD) were measured immediately post planting and at the end of each growing season. Analysis of variance (ANOVA) and Tukey-Kramer multiple comparisons procedure (MCP), where appropriate, were performed to determine any significant differences. After the first growing season, cherrybark oak did not exhibit a substantial difference regarding survival performance when compared to willow oak (75.5 percent and 76.5 percent, respectively). After two growing seasons, willow oak exhibited considerably greater survival (74.0 percent) overall when compared to cherrybark oak (70.5 percent). Bareroot seedlings had the highest survival (87.2 percent). Conventional containerized seedlings had unacceptable survival (47.5 percent) and EKOgrownTM seedlings had acceptable survival (82.0 percent). EKOgrownTM seedlings demonstrated the best overall GLD growth of all planting stocks (3.9 mm respectively). Bareroot seedlings had the second best overall GLD growth (1.5 mm) and conventional containerized had the least amount of overall GLD growth (0.8 mm). Overall height growth when comparing all three planting stocks bareroot, conventional containerized, and EKOgrownTM were similar to one another (-3.5cm, -0.8cm, and -3.6cm respectively). Therefore, based on an overall consideration of cost and performance, bareroot seedlings are considered the most effective option of the two species considered for artificial regeneration utilized in this study.

Current surface mine reclamation in Appalachia involves returning the land to approximate original contour by grading the surface and planting grasses and early-successional trees. This results in a greatly altered ecosystem compared to the native forest that was there prior to mining. The reclaimed land is usually degraded economically and environmentally because mine soils are usually less productive than the native soils, and because the mined sites do not provide the same level of ecosystem services. This research addressed constraints to the return of the native ecosystem by assessing how mine spoil properties and treatments affect native tree species and soil microorganisms. A 4x2x3 factorial greenhouse experiment was used to examine the growth of one-year-old Fraxinus americana, Quercus rubra, and Liriodendron tulipifera as well as herbaceous plant occurrence and microbial biomass and activity. Three mine spoils, brown, weathered sandstone (BWS), white, unweathered sandstone (WUS), and gray, unweathered shale (GUH) were compared with undisturbed forest topsoil (UFT) to determine their suitability for tree growth. Half of each of the four media was inoculated with a 2.5-cm layer of topsoil. BWS was the optimal spoil material for the growth of F. americana, Q. rubra and microbial populations. Foliar nutrient analysis indicated that L. tulipifera was highly dependent on nutrient levels and was unable to grow well on any of the spoil types due to deficiencies. Inoculation with topsoil increased tree growth on the GUH spoil, and increased microbial activity and presence of herbaceous plants across all growth media. The field study was used to determine what spoil properties most influenced three-year-old Quercus alba growth. This information was used to test a mine quality classification model. Northeast facing sites with sandy spoils high in nutrients, moderate in pH, and high in microbial populations were optimal for tree growth. These variables explained 52% of the variation in tree growth. Tree growth was also highly correlated with tree foliar nutrient levels, further suggesting that tree growth was influenced by spoil nutrients. Microbial biomass and dehydrogenase production were also regressed against soil properties and were dependant on a moderate pH, high nitrogen levels, and low salt content. These variables explained 53% of the variability in microbial biomass and 50% of the variability in enzyme production. These studies suggest that tree growth and soil microbial populations are closely linked, and both are affected by mine spoil properties. During mined land reclamation, mine spoils conducive to tree growth should be selected if return of the native ecosystem is the reclamation goal. / Master of Science

Durant ce troisième millénaire d’angoissants problèmes politiques, économiques et de sécurité se posent aux habitants de la planète terre. Leur ampleur et leur gravité, font oublier la perte de la biodiversité et l’amenuisement de ses ressources naturelles face aux activités anthropiques. Il s’avère cependant urgent de s’en préoccuper car la moindre négligence entraînerait des pertes irréparables de la biodiversité. La situation est inquiétante pour les pays sous-développés comme le Tchad et plus particulièrement pour le parc national de Manda et sa périphérie. Des aléas climatiques, des mauvaises pratiques agricoles et la surexploitation des ressources naturelles l’exposent à une succession de crises écologiques depuis le début des années 1980. L’accroissement actuel de la population, le surpâturage, l’instabilité politique, les guerres civiles multiplient les effets pervers et compliquent la gestion de cette biodiversité. [...] / During this third millennium of agonizing political, economic and security faced by the inhabitants of planet earth. Their intensity and gravity do forget the loss of biodiversity and the depletion of its natural resources in front of human activities. There is however urgent attention because the slightest negligence would result in irreparable loss of biodiversity. The situation is worrying for underdeveloped countries like Chad and especially for the Manda National Park and its periphery. Vagaries of the weather, bad agricultural practices and overexploitation of natural resources are exposed to a succession of environmental crises since the early 1980’s. The current population growth, overgrazing, political instability, civil wars perverse multiply and complicate the management of biodiversity. [...]