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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Lövskogsgynnande åtgärders effekt på vitryggig hackspett : En studie över hur lövskogsåtgärder påverkar födoinsekter för den vitryggiga hackspetten (Dendrocopos leucotos) i Västerbotten

Huber, Ottar January 2020 (has links)
Due to heavily managed forests in Sweden, there has been a rapid decline of deadwood and deciduous-rich areas since the 1950s. As a result of this, 2000 forest species are now red-listed of which 700 is in heavy need of deadwood. The white-backed woodpecker Dendrocopos leucotos, an umbrella species whose food choice consists of insects living in dead and decaying wood, has become critically endangered due to the lack of food and nesting areas. Preservation actions aimed towards saving the white-backed woodpecker are not only essential for itself but for 200 other species dependent on the same environmental requirements. The purpose of this study was to determine if the restoration for deciduous trees has favoured the white-backed woodpecker in four different areas: Ängsbacka, Degersjön, Ålidberget, and Kvillträsk in Västerbotten. By placing two different kinds of insect traps (window traps, and malaise traps) to analyze the different insects in restoration areas compared with control areas, I could investigate if there had been an increase in the number of insects preferred by the white-backed woodpecker. I could also investigate if there was a higher diversity of these preferred insects. There was no sign of an increase in numbers of preferred insects nor in numbers of preferred species. A higher diversity could neither be proven, however all four forests were deciduous-rich with high amount of dead-wood and has proven to show good potential for a future increase in saproxylic insects if restoration continues.
62

Dynamics of Understory Tree Seedling Recruitment and Growth of Advance Regeneration Following Variable-Density Thinning of Second-Growth Conifer Stands in the Pacific Northwest

James, Carson 09 December 2016 (has links)
With a growing desire to generate structural characteristics of late-successional conifer forests, managers are commonly seeking an approach to increase structural heterogeneity in otherwise simple second-growth stands. This study examined understory response to experimental thinning on the Olympic Peninsula of Western Washington. Variable-density thinning within the Olympic Habitat Development Study was found to have significant effects on both the density of seedling recruitment as well as early growth of western hemlock (Tsuga heterophylla (Raf.) Sarg.). In additional analysis, pre-commercial understory thinning, implemented by the Olympic National Forest, produced no observable acceleration in basal area growth. Results suggest that understory development is sensitive to previous management history as well as post-treatment stand structure. Better understanding the sources of variability in understory tree response to non-uniform thinning and understory density management will be principle in evaluating the efficacy of these treatments relative to traditional methods.
63

Restoring Landscapes in the Context of Environmental Change – A Mental Models Analysis

Hutchins, Emily G. 17 August 2015 (has links)
No description available.
64

The sound of diversity : the use of soundscapes to measure animal diversity in restored tropical rainforest in Sabah, Malaysia

Tengström, Åsa January 2023 (has links)
Animal diversity is rapidly decreasing across the globe as their habitats are being degraded by human activities. At the same time, forest restoration is an increasing practice, contributing to preserving nature values, but to what extent? On Borneo, only a fraction of its previous tropical rainforest remains today as conversion into monoculture tree plantations has been increasingly profitable. This study aims at investigating the potential of tropical reforestation in sustaining native animal diversity, a group that is often overlooked when it comes to studying restoration success. I collected audio recordings from four different land uses in Sabah, Borneo, Malaysia (oil palm and eucalypt plantations, primary and restored forest) to compare their soundscapes, i.e., all the sounds stemming from the different landscapes. I also created a list of 57 species based on the recordings, used it to compare species richness and presence of threatened species within the land uses. Both the animal diversity and soundscape composition differed significantly between restored forest and tree plantations, with more than twice as many species found in the rainforest both in total and per plot. The largest difference was observed comparing oil palm and restored forest plots; the latter harbored an average of 3.7 times more species. The soundscape from the restored forest showed high similarity to primary forest and the mean number of threatened species were the same in both land uses. More species were on average found in the restored plots than in the primary sites, 26 compared to 21. The findings from this study are promising, giving insight in the possibility to restore animal diversity simultaneously to restoring plant diversity. At the same time, it also stresses the need for a more sustainable alternative to the present plantation forestry and more comprehensive studies on how tropical rainforest restoration affects animal diversity.
65

Habitat suitability modeling for optimizing stand initiation and restoration efforts of economically and ecologically important hardwoods

Adeyemo, Segun Michael 13 December 2024 (has links) (PDF)
This dissertation addresses critical challenges in forest management and restoration in the Lower Mississippi Alluvial Valley (LMAV) through a series of interconnected studies focused on improving habitat suitability modeling and growth prediction for oak species. The research employs advanced modeling techniques to enhance our understanding of species-habitat relationships and forest dynamics in the context of climate change. Initial studies focused on developing ensemble habitat suitability models for American chestnut (Castanea dentata) and butternut (Juglans cinerea), two historically important but currently threatened tree species. These models predict suitable habitats and potential range shifts under various climate change scenarios, highlighting the species' vulnerabilities and informing conservation strategies. Building on these approaches, the research expands to model habitat suitability for eight key oak species in the LMAV. This multi-species analysis reveals both shared and distinct ecological requirements among the oak species, providing valuable insights for targeted restoration efforts. Niche overlap analysis further elucidates potential species interactions and habitat partitioning within the region. The dissertation culminates in the development of improved climate-sensitive growth and yield models for bottomland oaks. By incorporating habitat suitability predictions as a modifier, these models demonstrate significantly enhanced accuracy compared to traditional approaches. This integrated modeling framework offers a more comprehensive understanding of oak growth dynamics under changing environmental conditions. Throughout the research, the importance of key environmental drivers, such as temperature, precipitation, and soil characteristics, is consistently highlighted. The studies also underscore the potential impacts of climate change on species distributions and forest composition in the LMAV. This research contributes to the advancement of forest modeling techniques and provides practical insights for sustainable forest management, conservation of threatened species, and climate change adaptation strategies. The findings have important implications for decision-making in forestry and conservation, particularly in the LMAV but with potential applications to other regions. Future research directions are suggested, including the use of higher-resolution datasets and validation across diverse ecosystems to further improve model applicability and accuracy.
66

[en] ASSESSMENT OF FACTORS AND COLLABORATIVE STRATEGIES THAT IMPACT FOREST RESTORATIONS CHAINS IN ATLANTIC RAINFOREST PRIVATE LANDS / [pt] AVALIAÇÃO DOS FATORES E ESTRATÉGIAS COLABORATIVAS QUE IMPACTAM CADEIAS DE RESTAURAÇÃO FLORESTAL EM ÁREAS PRIVADAS NA MATA ATLÂNTICA

FERNANDA RESENDE DE SOUZA CARDOSO 11 February 2021 (has links)
[pt] O Brasil assumiu no Acordo de Paris a meta de restaurar 12 milhões de hectares de florestas até 2030, dos quais 5 milhões devem ocorrer na Mata Atlântica. Porém, a maior parte da área remanescente das florestas está localizada em áreas privadas e há uma série de fatores que dificultam a efetivação da restauração por parte dos proprietários. O objetivo dessa pesquisa foi identificar e avaliar as estratégias colaborativas que são utilizadas pelos principais participantes da cadeia de restauração florestal na Mata Atlântica do estado do Rio de Janeiro, de modo a superar barreiras, aproveitar oportunidades para o sucesso desses projetos e atingir uma sustentabilidade econômica, ambiental e social na região. Para isso, foi realizada uma pesquisa descritiva, com abordagem qualitativa, a partir de entrevistas em profundidade com especialistas e participantes dessa cadeia e de dados coletados em documentos e sites de projetos de restauração. Algumas das principais barreiras encontradas são: dificuldades logísticas na cadeia; escassez de mão-de-obra qualificada; baixa demanda por projetos de restauração; falta de implementação da legislação; dificuldade de integração de esforços privados e públicos; comunicação deficiente entre atores locais; retrocessos na compreensão da importância da conservação da biodiversidade. Foram identificadas algumas estratégias colaborativas usadas (cooperativas, redes formais e informais, participação em Conselhos) e avaliadas sua efetividade. Ao final foram feitas recomendações para o aprimoramento das estratégias atuais e para a adoção de novas estratégias colaborativas a fim de contribuir, junto a outras iniciativas de caráter econômico e regulatório, para a superação das barreiras. / [en] Brazil assumed in The Paris Agreement the commitment of 12 million hectares of forests restored by 2030, of which 5 million will occur in the Atlantic Rainforest. However, most of the remaining forest areas are located in private lands and there are a number of factors that difficult the adoption of restoration by landowners. The objective of this research was to identify and evaluate the collaborative strategies that used by the main participants of the forest restoration chains in the Atlantic Rainforest in the State of Rio de Janeiro, with the purpose to overcome barriers, take advantage of successful opportunities of these projects and achieve the region s economic, environmental and social sustainability. A descriptive research was carried out with a qualitative approach, based on in-depth interviews with specialists and chains participants and data collected in documents and restoration projects websites. The main barriers encountered include: logistical difficulties in the network; lack of qualified labor; low demand for restoration projects; lack of implementation of legislation; difficulties in integrating private and public efforts; poor communication between local actors; discussion setbacks related to the importance of biodiversity conservation. The most important collaborative strategies were identified (cooperatives, formal and informal networks, participation in Councils) and their effectiveness assessed. Recommendations were made to improve current strategies and adopt new collaborative strategies in order to contribute, with other economic and regulatory initiatives, to overcoming barriers.
67

Restauração florestal e estoque de carbono em modelos de implantação de mudas sob diferentes combinações de espécies e espaçamentos / Forestry restoration and carbon stock in seedlings implantation models under different combinations of species and spacing

Bufo, Luís Vicente Brandolise 30 April 2008 (has links)
Além dos já conhecidos benefícios da conservação e restauração das florestas ciliares sobre a qualidade e quantidade de água produzida pelas microbacias hidrogáficas, atualmente apregoa-se também a essas florestas a função de sumidouro de carbono. Este trabalho desenvolvido em duas propriedades produtoras de cana-de-açúcar localizadas no Norte do Estado de São Paulo (Santa Emília, município de Ituverava e Mata Chica, Morro Agudo) tem como objetivo testar variações de modelos de restauração já existentes, baseados na implantação de mudas e categorização das espécies em dois grupos denominados grupo de preenchimento e grupo de diversidade, quanto à eficiência em cobertura de copas e estoque de carbono de cada um dos modelos testados. Foram testados seis modelos de plantio, com variações em relação à forma de distribuição dos grupos (linhas alternadas de preenchimento e diversidade, alternância de indivíduos de preenchimento e diversidade na mesma linha e distribuição aleatória de indivíduos de preenchimento e diversidade), espaçamento (3 x 2 m e 3 x 3 m), e composição de espécies do grupo de preenchimento (grupo de preenchimento geral com 19 espécies, e grupo de preenchimento restrito com 10 espécies que mais se destacam em crescimento e cobertura de copas). A eficiência da cobertura de copas de cada modelo foi avaliada por dois métodos diferentes denominado: interseção na linha e interseção em pontos. No primeiro foi medido o comprimento de copas de todos os indivíduos na linha de plantio, e a porcentagem de cobertura obtida pela soma do comprimento total das copas de todas as árvores de cada parcela, em relação ao comprimento total das linhas de plantio de cada parcela. A avaliação por interseção em pontos foi realizada utilizando-se um densitômetro vertical com o qual foi verificou-se a presença ou ausência de cobertura em 108 pontos por parcela. Para a avaliação do montante de carbono estocado aos 32 meses de idade pelos diferentes modelos de plantio foram, tomadas medidas do maior diâmetro de tronco à 1,3 m, com valor de inclusão >= 5 cm, e aplicados à duas equações alométricas para a determinação da biomassa. A cobertura pelo método da interseção na linha mostrou ser influenciada pelo espaçamento utilizado sendo os espaçamentos de 3 x 3 m menos eficientes. A forma de distribuição e a composição de espécies do grupo de preenchimento não influenciaram a cobertura de copas. O método de interseção em pontos não verificou diferença significativa na cobertura entre os modelos de plantio testados. Comparando-se os blocos experimentais, para ambas as formas de avaliação da cobertura, os blocos 1 e 2 foram superiores aos blocos 3 e 4 explicando-se isso pela maior fertilidade dos solo dos blocos 1 e 2 (Faz. Santa Emília), e pelo intenso ataque de formigas observado nos blocos 3 e 4 (Faz. Mata Chica).A biomassa acumulada não foi influenciada pelo modelo de plantio, mas pelas condições de sítio acima mencionadas, tendo os blocos 1 e 2 significativamente mais biomassa estocada que 3 e 4. / Beyond the well known benefits of riparian forests conservation and restoration over water abundance and quality, these forests have been recently credited for carbon stocking. This study was developed on two sugar cane cultivation areas located on the Northern part of São Paulo State (Santa Emília Farm, in Ituverava town and Mata Chica Farm, in Morro Agudo town) and the main objective was to evaluate variations of pre-existing restoration models, which are based on plantation of seedlings classified into fulfillment or diversity group. The evaluation regarding the efficiency of carbon storing and crown cover of each used models. Six plantation models were tested, with variations related to fulfillment or diversity group\'s distribution (alternated rows of fulfillment and diversity species, alternated fulfillment or diversity individuals within the same row and random distribution), distance between plants (3 x 2 m e 3 x 3 m) and fulfillment species composition (19 species or 10 selected species with high performance related to growth and crown cover development).The efficiency of crown cover of each model was estimated for two different methods denominated: line interception and spot interception. In the first was measured the crown\'s length of all trees in the line plants, and the percentage of cover by some of total crown\'s length of all trees in the parcel, in relation the total line\'s length of each parcel. The spot interception was realized using a vertical densitometer, to verification the presence or absence of cover in the 108 spots of parcel. For evaluating the carbon storage, by different plantation models were measured all trees with the breast heigth (1,3 m) diameter with the inclusion value >= 5 cm, and applied in two allometric equations to estimate the carbon storage. The coverage by intersection line method was influenced by the distance between plants, and the 3 x 3 m distance was less efficient. The crown coverage was not influenced by distribution way species composition of fulfillment group. Considering both coverage evaluation forms, the comparison of experimental blocks indicated that blocks 1 and 2 had higher performance than blocks 3 and 4, probably because of better soil fertility properties on blocks 1 and 2 (Santa Emilia Farm) and because of intense ants\' attack observed on blocks 3 and 4 (Mata Chica Farm). Accumulated biomass was not influenced by plantation models, but by site conditions previously discussed, which resulted on higher stored biomass for individuals on blocks 1 and 2 than those on blocks 3 and 4.
68

Modulação do estoque de carbono em paisagens fragmentadas da Mata Atlântica em função dos efeitos de borda / Edge effects modulation of carbon stocks in fragmented Atlantic forest landscapes

Carvalho, Francisco D\'Albertas Gomes de 25 June 2015 (has links)
Apesar da reconhecida importância da fragmentação no balanço de carbono (C) das florestas tropicais, a maior parte do conhecimento a cerca deste assunto provém de estudos conduzidos na floresta Amazônica e desconsidera processos relacionados à influência da configuração da paisagem. Em particular, estimativas precisas da emissão de CO2 devido à fragmentação devem levar em consideração efeitos aditivos de borda e a idade das bordas. Nós investigamos estes efeitos sobre parâmetros estruturais de florestas (densidade, altura e área basal das árvores) e no estoque de C em oito fragmentos florestais (13 a 362 ha) antigos (>=70 anos), cercados de pastagens, em uma região de Mata Atlântica. Amostramos 5297 troncos, divididos em quatro tratamentos em cada um dos fragmentos: interior dos fragmentos; bordas antigas (>50 anos) em quina; bordas antigas retas; bordas novas (<50 anos) retas. Calculamos a biomassa acima do solo (BAS) através de equações alométricas que consideram a altura do tronco e seu diâmetro à altura do peito (DAP) e convertemos esse valor em carbono estocado na vegetação. O estoque de C foi altamente variável entre tratamentos, abrangendo valores entre 6.61 Mg ha-1 até 87.96 Mg ha-1 (média= 29.55 ± 14.97 Mg ha-1). As áreas de interior continham um estoque de C maior, bem como maior área basal, densidade de árvores e árvores mais altas do que as de borda. No entanto, a seleção de modelos não detectou influência da idade ou de efeitos aditivos no estoque de C. Nossos resultados sugerem que os padrões de efeitos de borda para a Mata Atlântica são diferentes dos observados em florestas tropicais fragmentadas mais recentemente, como é o caso da Amazônia. A Mata Atlântica tem um longo histórico de perturbação humana e uma dinâmica complexa de desmatamento e regeneração, que pode levar a uma condição de degradação generalizada, posto que até áreas mais distantes das bordas em manchas remanescentes de Mata Atlântica já perderam quantidades significativas de carbono. Nestas paisagens antrópicas, os efeitos de borda que atuam sobre a mortalidade de árvores e na redução da BAS podem ser mais abrangentes do que inicialmente estimado pelos modelos construídos para a floresta Amazônica. / Despite the importance of fragmentation for tropical forest carbon (C) balance, most of our knowledge comes from few sites in the Amazon and disregard underlying processes that relates landscape configuration with C stocks. Particularly, accurate estimation of CO2 emission from fragmentation must account for additive edge effects and edge age. Here we investigated those effects on carbon stock and forest structure (density, height, basal area) in eight old-growth forest (>=70 years) fragments (13 to 362 ha), surrounded by pasture, in the Brazilian Atlantic forest region. We sampled 5,297 stems in four distinct treatments, distributed in each fragment: fragment interiors; old (> 50 years) corner edge; old straight edge; and new (< 50 years) straight edge. Aboveground biomass (AGB) was estimated from tree height and diameter at breast height (DBH), and converted to carbon. C stock was highly variable between treatments, scoring from 6.61 Mg ha-1 up to 87.96 Mg ha-1 (average of 29.55 ± 14.97 Mg ha-1). Interior treatments had higher C stock, basal area, tree stem density and taller trees than edges. We found no significant effects of edge age or additive edge effects on C stocks. These results suggest that edge effects in the heavily-disturbed Atlantic rainforest may differ than those observed in more recently fragmented tropical forests, such as the Amazonian forest. In heavily human-modified landscapes, edge effects on tree mortality and reduction on AGB may contribute to overall higher levels of degradation across entire forest fragments, reducing the observed difference between edge and interior habitats, and suggesting that existing Amazonian forest models may underestimate the true impacts of tropical forest fragmentation for C storage.
69

Biomassa e carbono no estrato arbóreo em área restaurada de Mata Atlântica / Biomass and carbon in the arboreal stratum in an Atlantic Forest restoration area

Rasera, Susane 03 December 2018 (has links)
Frente às mudanças climáticas, foi estabelecido via Acordo de Paris o compromisso do Brasil em reduzir as emissões de gases do efeito estufa em 37% até 2025 e 43% até 2030. A restauração de 12 milhões de hectares de florestas, dado o potencial das florestas em sequestrar carbono, é apresentada como uma das formas para atingir essas metas. Assim, entender o real potencial das florestas plantadas em sequestrar carbono, obtido via quantificação da biomassa, torna-se de grande importância e oportunidade. O objetivo do trabalho foi desenvolver modelos de predição de biomassa do estrato arbóreo para uma área restaurada com 12 anos de idade e avaliar a alocação de biomassa e carbono na vegetação arbórea em relação ao manejo silvicultural, arranjo de espécies e espaçamento de plantio nessa mesma área, localizada na Estação Experimental de Ciências Florestais de Anhembi, pertencente à ESALQ/USP. Para desenvolvimento das equações foi realizado o abate de 100 indivíduos arbóreos das 20 espécies presentes na área, escolhidos segundo uma amostragem estratificada em cinco classes de diâmetro por espécie. Em todas as árvores foi realizada cubagem rigorosa do tronco e galhos grossos e tiradas medidas de DAP, Altura total e Altura do tronco. Em seguida, foram divididas em quatro compartimentos: raízes, tronco, galhos grossos e copa, composta por galhos finos e folhas, e pesadaos separadamente. De cada compartimento foram obtidas amostras para determinação do teor de umidade e densidade básica dos discos, retirados em três posições do tronco: base, meio e topo e um na parte dos galhos grossos. Foram desenvolvidas quatro equações para predição de biomassa: Biomassa total acima do solo (Btas), Biomassa de tronco (Btr), Biomassa de copa (Bcp) e Biomassa de raiz (Brz). Para ajuste dos modelos foram testadas duas equações lineares, comumente utilizadas no meio florestal para cálculo de volume, e variações dessas equações com a inclusão de cinco variáveis preditoras: DAP, Altura, Altura do tronco, Comprimento de Copa e Densidade básica da madeira do tronco. As melhores equações obtidas incluíram pelo menos o DAP e densidade básica da madeira, sendo esta essencial para melhoria nos critérios de seleção de modelos. A aplicação das equações aos dados do inventário realizado em 2016 na área levou a estimativas de fixação de biomassa e carbono do estrato arbóreo bem variáveis entre os tratamentos, indo de 27,7 a 157,7 Mg.ha-1 para biomassa e de 13,0 a 74,1 Mg.C.ha-1 para carbono. As melhores parcelas apresentaram valores próximos aos encontrados em outros estudos em áreas de reflorestamento, mas abaixo do encontrado em florestas maduras. / In response to climate change, Brazil\'s commitment to reduce greenhouse gas emissions by 37% by 2025 and 43% by 2030 was established through the Paris Agreement. The restoration of 12 million hectares of forests, given the potential of forests in sequestering carbon, is presented as one of the ways to achieve these goals. Thus, understanding the real potential of planted forests to sequester carbon, obtained through the quantification of biomass, becomes of great importance and opportunity. The objective of this work was to develop biomass prediction models of the arboreal stratum for a restored area of 12 years old and to evaluate the biomass and carbon allocation in tree vegetation in relation to silvicultural management, species arrangement and planting spacing. The study area is part of an experimental study titled \"Models for the Recovery of Atlantic Forest Degraded Areas\", located at the Experimental Station of Forestry Sciences of Anhembi, belonging to ESALQ / USP. For the development of the equations, 100 individuals of the 20 species present in the area were felled according to a stratified sampling in five diameter classes per species. In all the trees was carried out rigorous volume measurements of the trunk and thick branches and taken dimensions of DBH, Total Height and Trunk Heignt. They were divided into four compartments: roots, trunk, thick branches and canopy, composed of thin branches and leaves, and weighed separately. From each compartment were taken samples to determine the moisture content and basic density of the discs, taken in three positions of the trunk: base, middle and top and one in the part of the thick branches. Four biomass prediction equations were developed: Total Biomass Above the Soil (Btas), Trunk Biomass (Btr), Canopy Biomass (Bcp) and Root Biomass (Brz). Two linear equations commonly used to calculate tree volume and its variations with the inclusion of five predictive variables: DBH, Height, Trunk Height, Cup Length and Basic Density of the trunk wood were used to develop the equations. The best equations obtained included at least the DBH and basic wood density, which is essential for improvement in the model selection criteria. The application of the equations in the inventory carried out in 2016 in the area led to estimates of biomass and carbon values of the tree stratum very variable between the treatments, ranging from 27.7 to 157.7 Mg.ha-1 for biomass and 13.0 to 74.1 Mg.C.ha-1 for carbon. The best plots presented values close to those found in other studies in reforestation areas, but lower than those found in mature forests.
70

O processo de regeneração natural e a restauração de ecossistemas em antigas áreas de produção florestal / The process of natural regeneration and ecosystem restoration in former forest production areas

Martins, Andreza Maria 12 May 2009 (has links)
Em empresas florestais que plantam florestas de rápido crescimento voltadas ao abastecimento industrial, é comum, hoje em dia, a existência de áreas de plantios comerciais que devem ser revertidos para áreas de vegetação natural. Entretanto, dependendo das condições locais e do contexto da paisagem, nem sempre os processos naturais de regeneração são suficientes para garantir que a vegetação natural se desenvolva e se auto-sustente nessas áreas. Este estudo avaliou os processos de regeneração natural e a efetividade de algumas técnicas de restauração florestal para indicar a melhor estratégia aplicável em larga escala, em áreas anteriormente manejadas com as culturas de Eucalyptus sp e Pinus sp, que foram abandonadas com o intuito de serem incorporadas como reservas legais. O projeto foi desenvolvido no município de Borebi, SP, em duas fazendas, sendo uma em ecossistema de cerrado latu sensu e outra de floresta estacional semidecidual. Em cada área foi instalado um experimento em blocos ao acaso, com cinco repetições e cinco tratamentos, com parcelas de 30 x 30m. Os tratamentos foram: T1: controle, T2: semeadura direta de dez espécies florestais de rápido crescimento; T3: plantio convencional de 19 espécies florestais de crescimento lento, médio e rápido; T4: condução da regeneração natural através de tratos silviculturais e T5: picagem da cobertura vegetal e revolvimento do solo. A regeneração natural de indivíduos lenhosos existente foi levantada em duas classes: altura a 1,30 m (parcela toda) e altura > que 0,50m e < que 1,30m (em três subparcelas de 1 x 30m ), antes e após (12 meses) a implantação dos tratamentos. O banco de sementes do solo foi amostrado antes da instalação e duas vezes após, e o solo superficial retirado de uma área de 315cm² e profundidade de 5cm, formando duas amostras compostas por parcela. Para a chuva de sementes foram instalados cinco coletores por parcela, com dimensões de 0,50 x 0,50m cada. Tanto o banco como a chuva de sementes apresentaram baixa porcentagem de espécies lenhosas e alta densidade de algumas espécies herbáceas invasoras. A regeneração natural apresentou espécies típicas da fase inicial da sucessão, com predomínio de espécies não constituintes. A maior similaridade na composição das espécies ocorreu na comparação entre a vegetação e a chuva de sementes e a menor na comparação da vegetação com o banco de sementes. O tratamento T4 (condução da regeneração) apresentou efeito significativo na área basal, densidade, número de espécies e diversidade de espécies da regeneração natural, em ambas as áreas, após 12 meses de implantação, mostrando-se mais viável ecologicamente e economicamente em relação aos demais. / In Forest Companies that cultivate fast-growing forest species for industrial supply, it has been usual the existence of commercial production areas that need to be converted in protected areas with native vegetation. Nevertheless, depending on local conditions and landscape context, the natural regeneration process is not enough to guarantee the successional development This work aimed at investigating the natural regeneration process and the effectiveness of some forest restoration techniques to be applied in large scale in, former Eucalyptus sp and Pinus sp plantations, which were abandoned to be incorporated as protected areas. The project was developed at Borebi municipality, SP, in two forest farms, one comprising latu sensu savana formations, and the other corresponding to seasonal semideciduous forest. In each experimental area a complete randomized block experiment with five treatments and five replicates was installed, with 30 x 30 m plots. The treatments were: T1: control; T2: direct seeding of 10 fast growing forest species; T3: conventional planting of 19 species with different growth characteristics; T4: management of natural regeneration by silvicultural treatments; T5: tillage of ground vegetation cover and plowing. Natural regeneration was surveyed before and 12 months after the experiment installation, when all woody individuals with height 1.30m were measured; the individuals with height 0.50m and <1.30m were surveyed in three 1 x 30m subplots within each plot. The soil seed bank was sampled before and two times after the treatments, were 315cm² and 5cm depth samples formed 2 composite samples by each plot. Seed rain was studied by five 0,50 x 0,50m litter traps installed in each plot. The soil seed bank and seed rain had a low percentage of woody species and high density of some nonconstituent invasive herbaceous species. The natural regeneration showed a predominance of early successional species, but was dominated by nonconstituent species. The higher similarity in species composition occurred between the natural regeneration and the seed rain, and the smaller between the natural regeneration and the soil seed bank. The regeneration management treatment (T4) showed a significant effect in basal area, density, species diversity and species richness of natural regeneration after 12 months, indicating to be the most viable ecologically and economically in comparison with the other, for the local conditions.

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