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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.
51

Análise florística, fitossociológica e qualitativa da arborização na Praça XV de Novembro em Ribeirão Preto, SP

Romani, Gustavo de Nobrega [UNESP] 26 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-26Bitstream added on 2014-06-13T20:08:45Z : No. of bitstreams: 1 romani_gn_me_jabo.pdf: 615001 bytes, checksum: c2624eb8336a9c3101f7aae647433b94 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As praças públicas são representações de áreas verdes tendo como finalidade principal o lazer. Por estarem em uma área urbana e com ambiente degradado são sistemas frágeis e complexos e exigem administração e planejamento cuidadoso, com os objetivos de otimizar as funções da arborização e reduzir custos com a mesma. Visando o conhecimento detalhado da vegetação arbórea para fins de orientação do manejo e conservação dessa área, foi feito um levantamento florístico, fitossociológico e qualitativo da arborização (árvores e palmeiras) da praça XV de Novembro, situada em Ribeirão Preto, SP. Foram identificados, mensurados e visualmente avaliadas todas as árvores e palmeiras presentes na praça que ocupa uma área de 15.456 m2, onde verificou-se a presença de 19 famílias botânicas, 42 espécies num total de 161 indivíduos. A espécie Caesalpinia peltophoroides (sibipiruna) apresentou maior densidade (14,91%) na população local e também, foi a espécie que apresentou maiores problemas fitossanitários causado por cupim, no entanto, Ficus dendrocida (figueira-mata-pau ou figueira-branca) foi a espécie de maior valor de importância por seus altos valores de dominância relativa na população que deve-se ao alto valor de sua área basal. O valor do índice de diversidade de Shannon-Weaver foi de 3,14 que se comparado a outros levantamentos consiste em um bom índice. As árvores e palmeiras apresentam alturas variadas, mas a maioria está em um porte adulto com mais de 10 metros de altura. Em se tratando de qualidade da arborização, a Praça XV de Novembro, deixa a desejar devido aos problemas fitossanitários existentes, com destaque para o caso dos cupins arborícolas nas sibipirunas que podem causar quedas de galhos e conseqüentes acidentes com os cidadãos / The squares are a public green areas have leisure as main aim. The fragility and complexity of this system require to be administered planning carefully, aiming to optimize the afforestation functions and reduce costs, so it is essential planning, defining the activities and the possible qualitative and quantitative targets, because the lack of plan to follow and to complete makes the processes of implementation and management planning totally empirical. The aim of this survey was to quantify the arboreal vegetation composition in order to direct the conservation and management. It was carried out a floristic, phytosociological and qualitative survey of existing trees and palms. It was identified, measured and visually evaluated all arborial vegetation of the square. Occupying an area of 15,456 m2, it was found 19 botanical families, 42 species distributed into 161 individuals. Although Caesalpinia peltophoroides (sibipiruna) had obtained the highest density level, Ficus dendrocida (figueira-mata-pau ou figueira branca) was the most dominant species in the population due to its high basal area value. The diversity index of Shannon-Weaver, was 3,14, which is a good result due to other inventories. The trees and palms presented different heights, but most of them are in an adult size of over 10 meters high. When it comes to its afforestation quality, the XV de Novembro Square has not good points to show because of the existing pest and diseases over its vegetation, especially for the termites that may cause branches fall put citizens on dangerous
52

Fauna edáfica sob modelos em estágio inicial de restauração de floresta subtropical / Edaphic fauna under models in initial stage of restoration subtropical forest

Franco, Regiane 01 April 2016 (has links)
CAPES / O objetivo deste estudo foi comparar áreas submetidas a diferentes tecnologias de restauração florestal em relação à abundância, riqueza, diversidade e composição da fauna presente na serapilheira e no solo. Foram conduzidos os seguintes tratamentos: Regeneração natural (RN), Plantio de árvores em linhas de recobrimento e diversidade (L) e Nucleação (N). Uma área de mata secundária (M) foi incluída no estudo como referencial das condições do solo. O delineamento experimental foi em blocos ao acaso, com quatro repetições. Foram coletadas amostras para extração da mesofauna (outubro/2012; julho e outubro/2013) e da macrofauna (junho e outubro/2013), em seis pontos de cada parcela amostral, totalizando 24 pontos amostrais por tratamento. Para coleta da macrofauna edáfica foi utilizado o método TSBF. A mesofauna foi coletada com o auxílio de um cilindro de metal e extraída utilizando Funis de Berlese-Tüllgren. Em cada ponto foi coletado separadamente serapilheira e solo e a fauna extraída foi identificada em nível de classe/ordem taxonômica. Os colêmbolos foram categorizados em tipos morfológicos. No total, considerando a mesofauna, a macrofauna e as três coletas realizadas, foram contabilizados 28618 organismos. Em relação à mesofauna edáfica, as tecnologias avaliadas não diferiram, após três anos em processo de restauração, em relação à abundância total de organismos e composição da comunidade. O índice diversidade de Shannon, na mesofauna edáfica, seguiu um gradiente de impacto antrópico, sendo superior na Regeneração natural, que não sofreu intervenções técnicas e apresentou maior teor de umidade no solo, e inferior na tecnologia plantio em linhas, que foi submetida ao controle de plantas espontâneas em área total. No caso da mesofauna da serapilheira as áreas submetidas às tecnologias não se diferenciaram em relação à riqueza média de grupos taxonômicos, abundância total de organismos e composição da comunidade. Considerando a macrofauna edáfica as tecnologias não diferiram em relação à abundância e riqueza, sendo que na avaliação de junho/2013 a RN apresentou maior índice H’ e se diferenciou em relação à composição da comunidade das demais tecnologias. Na avaliação de outubro/2013, as diferenças entre as tecnologias em relação ao índice H’ foram mais estreitas e essas não se diferenciaram em termos de composição da comunidade da macrofauna edáfica. Na macrofauna da serapilheira, em junho/2013, a RN apresentou maior riqueza e maior índice H’ quando comparada as demais tecnologias e na avaliação de outubro/2013, as tecnologias não se diferenciaram em relação à composição da comunidade, riqueza média de grupos e abundância média de organismos. No caso dos colêmbolos, as tecnologias após três anos em processo de restauração, não se diferenciaram em relação à abundância, riqueza e composição da comunidade de colêmbolos por diferentes morfotipos. A mata secundária, em relação às tecnologias de restauração florestal, apresentou maior abundância de saprófagos, predadores e maior diversidade de morfotipos de colêmbolos. Diante desses resultados recomenda-se a regeneração natural por ser a tecnologia de menor custo de implantação, seguida da nucleação e do plantio em linha. A fauna deve ser monitorada, ao longo do tempo, nas tecnologias de restauração, bem como as variáveis físicas e químicas do solo, a fim de entender possíveis mudanças na composição e diversidade de organismos. / The goal of this study was to compare areas under different forest restoration technologies in relation to abundance, richness, diversity and composition of the present fauna in the litter and soil. The treatments evaluated were: natural regeneration (RN); high diversity tree plantations (L) and nucleation (N). An area of secondary forest was included in the study as a reference of soil conditions. The experimental design was in randomized block with four replications. Samples were collected for extraction of mesofauna (October/2012; July and October/2013) and macrofauna (June and October/2013) in six points of each plot, totaling 24 samples per treatment. For collecting soil macrofauna was used TSBF method. The mesofauna was collected with a metal cylinder and extracted by Berlese-Tüllgren funnel. Litter and soil were collected separately at each point and the fauna was identified level of class/taxonomic order. The springtails were classified using morphotypes. In total, considering the mesofauna, macrofauna and three times collected were accounted 28618 organisms. In relation soil mesofauna, the evaluated technologies did not differ, after three years of restoration, in relation to total abundance of organisms and community composition. The Shannon diversity index (H), in soil mesofauna, followed a human impact gradient. This index was higher in natural regeneration, which not was undergone technical interventions and showed higher moisture in the soil. The tree planting technology, under the control of volunteer plants in total area, showed lower H index. In the case of litter mesofauna, the technologies did not differ in relation the mean richness, total abundance of organisms and community composition. Considering edaphic macrofauna, technologies did not differ in relation to the abundance and richness, and in the evaluation of June/2013, RN showed higher H index and differed in relation to the community composition of other technologies. In October/2013 evaluation, the differences between the technologies in relation to H index were narrower and these did not differ in terms of composition of soil macrofauna community. In litter macrofauna, in June/2013, the RN presented greater richness and H index when compared to other technologies and in evaluation October/2013 technologies did not differ in relation to community composition, richness and mean abundance of organisms. In the case of springtails, technologies after three years in the restoration process, did not differ in relation to the abundance, richness and composition of Collembola community for different morphotypes. The secondary forest, in relation to forest restoration technologies, presented greater abundance of saprophages, predators and greater diversity of morphotypes of springtails. From these results it, we recommended to natural regeneration by to have the lowest cost of deployment, followed by nucleation and online planting. The animals should be monitored over time, in the restoration technologies, as well as the physical and chemical characteristics of the soil, in order to understand the possible changes in the composition and diversity of organisms.
53

Respostas de comunidades de aves ao florestamento dos campos sulinos : integrando diversidade taxonômica, filogenética e funcional

Jacoboski, Lucilene Inês January 2018 (has links)
O florestamento dos campos do sul da América do Sul incluindo os campos do Pampa estão mudando a paisagem local e levando a mudanças nas populações de aves. O conhecimento sobre o efeito do florestamento sobre a avifauna dos campos do sul da América do Sul é bastante limitado à riqueza e composição de espécies. Além de preencher lacunas considerando diferentes índices para avaliar respostas das comunidades de aves ao florestamento dos campos (Capítulos 2 e 3), nesta tese nós também avaliamos se Áreas de Preservação Permanente localizadas dentro de plantações de eucalipto são funcionais para a avifauna local, fazendo uma comparação com áreas de campo pastejado (Capítulo 1). No capítulo 1 nós registramos uma diferença na composição de espécies entre as áreas devido principalmente às mudanças na altura e densidade da vegetação. Nos capítulos 2 e 3 nós avaliamos diferentes componentes da diversidade (taxonômica, filogenética e funcional) considerando possíveis efeitos do florestamento dos campos sobre estes Nossos resultados demonstram respostas diferenciadas entre os componentes, enquanto o florestamento leva a uma redução na diversidade taxonômica, diversidade filogenética e funcional não demonstram respostas negativas. No capítulo 2 no entanto, nós observamos que o florestamento dos campos conduz a uma perda de distintividade evolutiva, beneficiando desta forma linhagens que se diversificaram recentemente. No capítulo 3 apesar da redução na diversidade taxonômica não houve uma redução na diversidade funcional em áreas plantadas. Já a associação de alguns atributos funcionais com as áreas pós-corte, indica a plasticidade de algumas espécies que retornam para essas áreas logo após o corte dos plantios.De modo geral nossos resultados indicam que a manutenção de mosaicos de campo de diferentes alturas maximiza a biodiversidade local de aves e destaca a importância da proteção de áreas campestres. Além disso, vimos que considerar diferentes componentes da diversidade que incorporam informações sobre as espécies são importantes pois podem informar por exemplo, quantas extinções uma comunidade pode suportar até que funções importantes sejam perdidas, afetando assim a estabilidade dos ecossistemas. / The afforestation of southern grasslands of South America including the Pampa grasslands are changing the local landscape and leading to reduction of bird populations. Knowledge about the effect of afforestation on the avifauna of the southern South American grasslands is limited to richness and composition of species. In addition to filling gaps considering different indices to evaluate responses of the bird communities to the afforestation of the grasslands (Chapters 2 and 3), in this thesis we also evaluated whether Permanent Preservation Areas located within eucalyptus plantations are functional for the local avifauna, making a comparison with grazed grasslands areas (Chapter 1). In Chapter 1 we recorded a difference in species composition between areas due mainly to changes in height and density of vegetation. In chapters 2 and 3 we evaluated different components of diversity (taxonomic, phylogenetic, and functional), considering possible effects of grasslands afforestation on them. Our results demonstrate differentiated responses among components, while afforestation leads to a reduction in taxonomic diversity, phylogenetic and functional diversity do not demonstrate negative responses In chapter 2 however, we observe that grasslands afforestation leads to a loss of evolutionary distinctiveness, thus benefiting species that have diversified recently. In chapter 3, despite the reduction in taxonomic diversity, there was no reduction in functional diversity in planted areas. Furthermore, the association of some functional traits with the post-cut areas indicates the plasticity of some species that return to these areas soon after cut the plantations. In general our results indicate that the maintenance of grasslands mosaics of different heights maximize the local biodiversity of birds and highlight the importance of the protection of grasslands areas. In addition, we have seen that considering different components of diversity that incorporate information on species is important because they can tell, for example, how many extinctions a community can support until important functions are lost.
54

Mitigação de emissão de gases de efeito estufa e adaptação do café arábica e condições climáticas adversas / Mitigation of greenhouse gas emissions and adaptation of arabica coffe to adverse climatic conditions

Coltri, Priscila Pereira, 1980- 07 October 2012 (has links)
Orientadores: Jurandir Zullo Junior, Hilton Silveira Pinto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-21T01:28:59Z (GMT). No. of bitstreams: 1 Coltri_PriscilaPereira_D.pdf: 6879462 bytes, checksum: 2b84c69c7329baa4a9b060b038ddaa14 (MD5) Previous issue date: 2012 / Resumo: A elevação da concentração dos gases de efeito estufa (GEEs) na atmosfera, especialmente o dióxido de carbono, tem causado alterações significativas nos elementos atmosféricos, acarretando mudanças e variações no clima com importantes consequências. Projeções do IPCC (2007) para as áreas tropicais brasileiras indicam que a temperatura média global poderá aumentar entre 1°C e 5,8°C, o que traria grandes impactos na atividade agrícola e nos recursos naturais. Se as estimativas do IPCC (2007) estiverem corretas, as maiores áreas produtoras de café arábica do Brasil poderão se tornar de alto risco climático para o cultivo, causando sérios impactos na produção de café e no agronegócio brasileiro. O presente trabalho busca contribuir para o estudo da cafeicultura brasileira no contexto das mudanças climáticas projetadas para as próximas décadas. Três aspectos principais foram analisados: as possíveis mudanças climáticas para o sudeste do Brasil nesse século (2011-2099) com o modelo regional de mudanças climáticas ETA/CPTEC (dowscaling do HadCm3); atividades de adaptação da cultura em um cenário climático mais quente; e a relação da cultura com o estoque de carbono atmosférico, como uma atividade de mitigação. Analisando o ETA/CPTEC, foi possível verificar que, sem atividades de adaptação e mitigação, aumentará o risco climático para o cultivo do café arábica em oito dos dez municípios na região de estudo. Como uma atividade de adaptação a cenários climáticos mais quentes, foram avaliadas três formas de arborização para reduzir a temperatura no microclima do cultivo de café em comparação com o cultivo a pleno sol, mais utilizado no país. As variáveis micrometeorológicos nos sistemas de cultivo de café foram medidos em campo e também simulados no software "Envi-Met". Em comparação com o sistema a pleno sol, o tratamento mais arborizado (café plantado em consórcio com macadâmia) recebeu 29,4% a menos de radiação solar e reduziu a temperatura do ar em apenas 0,6°C no microclima de cultivo, indicando que nos cenários mais quentes projetados pelo ETA/CPTEC, esse sistema de plantio não será uma forma de adaptação da cultura. Analisando a relação do café arábica com atividades de mitigação dos GEEs, foi medida a quantidade de carbono (biomassa seca) que a cultura a pleno sol e cultivada com macadâmia pode estocar. Para tanto, utilizaram-se métodos destrutivos, em campo, e de sensoriamento remoto com imagens de alta resolução. Em campo, verificou-se que o sistema de cultivo de café com macadâmia estoca, em média, 2 toneladas de carbono por hectare a mais que o sistema a pleno sol. Esses resultados permitiram validar a premissa de que sistemas agroflorestais com café são considerados uma importante forma de mitigação dos gases de efeito estufa. Na análise dos dados de sensoriamento remoto, encontrou-se forte correlação entre o índice de vegetação NDVI, parâmetros biofísicos da cultura e a biomassa, permitindo, assim, a criação de um modelo de estimativa de biomassa para evitar futuras análises destrutivas / Abstract: The increase of greenhouse gas (GHG) concentration in the atmosphere, especially carbon dioxide, is causing wide changes in atmospheric elements, leading to climate change and variability with critical consequences. Projections of the Intergovernmental Panel on Climate Change (IPCC 2007) indicate that the global temperature is supposed to increase 1ºC to 5.8º in the tropical areas of Brazil, causing important impacts in Agriculture and natural resources. If the IPCC (2007) estimates are confirmed, the major areas of current coffee arábica production may become areas of high climatic risk, causing severe impact in coffee production and the Brazilian agribusiness. This project aims to contribute to the study of Brazilian coffee crops (coffea arabica) in the context of global climate change expected for the coming decades. Three main aspects were analyzed: Brazilian southeast climate change in the century (2011-2099) with a regional climate change model (ETA/CPTEC, dowscaling of HadCM3); the coffee crop adaptation to warmer climates; and the crop relationship with the carbon stock as a mitigation activity. Analyzing the ETA/CPTEC model we found that, with no adaptation and mitigation activities, it will not be possible to cultivate coffee arábica in 8 of the 10 cities in the studied region. As an adaptation alternative in hotter weather, we evaluated three different coffee systems planted with forestry tree in order to reduce micro-climate temperature, and compared them to the most common cultivation system in Brazil: coffee planted at "full sun". The micrometeorological parameters in each system was measured in the field and also simulated using the Envi-Met software. Comparing to full sun system, the most shaded coffee system (coffee planted with macadamia) received 29,7% less solar radiation, and reduced the temperature only 0,6°C in the cultivation microclimate, indicating that in the warmest scenario this cultivation system will not be an adaptation alternative. Analyzing the coffee relationship with GHG mitigation activities, we measured the coffee crop's carbon stock (dry biomass) in two cultivation systems: full sun and shaded with macadamia using both destructive methods and remote sensing with high resolution images. Destructive models showed that shaded system with macadamia stocks on average 2 ton per hectare more than full sun systems. These results supported the assumption that agroforesty systems with coffee are considered an important form of mitigation of GHG. Analyzing the remote sensing data we found a strong correlation between the NDVI vegetation index, biophysical plant parameters and biomass. We created a predictive model for biomass and carbon stocks in coffee systems in order to avoid the use of destructive methods / Doutorado / Planejamento e Desenvolvimento Rural Sustentável / Doutor em Engenharia Agrícola
55

Respostas de comunidades de aves ao florestamento dos campos sulinos : integrando diversidade taxonômica, filogenética e funcional

Jacoboski, Lucilene Inês January 2018 (has links)
O florestamento dos campos do sul da América do Sul incluindo os campos do Pampa estão mudando a paisagem local e levando a mudanças nas populações de aves. O conhecimento sobre o efeito do florestamento sobre a avifauna dos campos do sul da América do Sul é bastante limitado à riqueza e composição de espécies. Além de preencher lacunas considerando diferentes índices para avaliar respostas das comunidades de aves ao florestamento dos campos (Capítulos 2 e 3), nesta tese nós também avaliamos se Áreas de Preservação Permanente localizadas dentro de plantações de eucalipto são funcionais para a avifauna local, fazendo uma comparação com áreas de campo pastejado (Capítulo 1). No capítulo 1 nós registramos uma diferença na composição de espécies entre as áreas devido principalmente às mudanças na altura e densidade da vegetação. Nos capítulos 2 e 3 nós avaliamos diferentes componentes da diversidade (taxonômica, filogenética e funcional) considerando possíveis efeitos do florestamento dos campos sobre estes Nossos resultados demonstram respostas diferenciadas entre os componentes, enquanto o florestamento leva a uma redução na diversidade taxonômica, diversidade filogenética e funcional não demonstram respostas negativas. No capítulo 2 no entanto, nós observamos que o florestamento dos campos conduz a uma perda de distintividade evolutiva, beneficiando desta forma linhagens que se diversificaram recentemente. No capítulo 3 apesar da redução na diversidade taxonômica não houve uma redução na diversidade funcional em áreas plantadas. Já a associação de alguns atributos funcionais com as áreas pós-corte, indica a plasticidade de algumas espécies que retornam para essas áreas logo após o corte dos plantios.De modo geral nossos resultados indicam que a manutenção de mosaicos de campo de diferentes alturas maximiza a biodiversidade local de aves e destaca a importância da proteção de áreas campestres. Além disso, vimos que considerar diferentes componentes da diversidade que incorporam informações sobre as espécies são importantes pois podem informar por exemplo, quantas extinções uma comunidade pode suportar até que funções importantes sejam perdidas, afetando assim a estabilidade dos ecossistemas. / The afforestation of southern grasslands of South America including the Pampa grasslands are changing the local landscape and leading to reduction of bird populations. Knowledge about the effect of afforestation on the avifauna of the southern South American grasslands is limited to richness and composition of species. In addition to filling gaps considering different indices to evaluate responses of the bird communities to the afforestation of the grasslands (Chapters 2 and 3), in this thesis we also evaluated whether Permanent Preservation Areas located within eucalyptus plantations are functional for the local avifauna, making a comparison with grazed grasslands areas (Chapter 1). In Chapter 1 we recorded a difference in species composition between areas due mainly to changes in height and density of vegetation. In chapters 2 and 3 we evaluated different components of diversity (taxonomic, phylogenetic, and functional), considering possible effects of grasslands afforestation on them. Our results demonstrate differentiated responses among components, while afforestation leads to a reduction in taxonomic diversity, phylogenetic and functional diversity do not demonstrate negative responses In chapter 2 however, we observe that grasslands afforestation leads to a loss of evolutionary distinctiveness, thus benefiting species that have diversified recently. In chapter 3, despite the reduction in taxonomic diversity, there was no reduction in functional diversity in planted areas. Furthermore, the association of some functional traits with the post-cut areas indicates the plasticity of some species that return to these areas soon after cut the plantations. In general our results indicate that the maintenance of grasslands mosaics of different heights maximize the local biodiversity of birds and highlight the importance of the protection of grasslands areas. In addition, we have seen that considering different components of diversity that incorporate information on species is important because they can tell, for example, how many extinctions a community can support until important functions are lost.
56

The feasibility of carbon-subsidized afforestation projects : a case study of China

Hou, Guolong 11 November 2020 (has links)
Afforestation projects in China have substantially contributed to national CO2 sequestration and play an important role in international climate change mitigation. However, these nation-wide afforestation projects are usually funded by the national government, with very large and unsustainable investments. It is important to find alternative sources of funding to finance afforestation, and convince poor farmers to become involved in afforestation projects. Carbon-subsidized afforestation could be the solution. The current study aims to find i) whether farmers need additional subsidies to reforest their marginal farmland; if so, ii) whether the value of carbon sequestration of afforestation can offset farmers' net costs. To do this, first I determine the amount of carbon sequestration though afforestation. Second, I assess the value of carbon sequestration, the costs and benefits of afforestation projects, and the costs and benefits of crop production. Third, I investigate the optimal rotation period of the plantations considering a joint production of timber and carbon, for different species. Results show that total carbon sequestration through tree biomass and soil carbon following afforestation differs among tree species and stand age as well as across regions. Economic trees sequester less carbon than ecological trees and bamboo. Among economic trees, nut trees with an inedible hard shell sequester more carbon than fruit trees. The regional context significantly influences the carbon sequestration potential, with more carbon sequestered in southern and eastern regions than in northern regions. Bamboo also shows a remarkable carbon sequestration potential, which is even greater than Chinese fir and Poplar in northern regions. Although afforestation programs have huge potential to store carbon, the voluntary acceptance by landowners crucially depends on their economic outcome. I found that usually carbon credits can compensate for the opportunity costs of alternative land uses, except i) when highly profitable croplands are afforested, in which case carbon credits are not sufficient, and ii) when croplands that generates low incomes are afforested, in which case carbon credits are not needed. Fruit trees are the most cost-effective option for afforestation. Bamboo afforestation is economically attractive if carbon revenues is included. The minimum price of carbon credit decreases with increasing project duration because more carbon is stored when time increases. This does not hold for fast-growing trees like Eucalyptus, for which the minimum price increases with extended project duration. Given the temporal variations of joint production of timber and carbon sequestration, the carbon accounting regimes (tCER, temporary Certified Emission Reductions and lCER, long-term Certified Emission Reductions) have a significant impact on the optimal rotation as well as on the revenue. Forest managers have an incentive to use tCER accounting to finance slow-growing plantations, and lCER for fast-growing ones. I perform a sensitivity analysis detects the changes of rotation period with different carbon prices and discount rates. While the optimal decision for slow-growing species (e.g. Chinese fir) is highly sensitive to changes in both variables under tCER accounting, the results concerning fast-growing species (e.g. Eucalyptus) are most sensitive under the lCER accounting regime. In contrast, carbon revenues have a minimal impact on the optimal rotation of Poplar plantations, no matter which regime is applied. I conclude that carbon-subsidized afforestation is a feasible way to offset the opportunity costs of retired farmland and support the livelihood of farmers. The findings can contribute to the efficient and sustainable management of forestry projects using carbon sequestration, while the methodology can also be applied to other regions in the world.
57

Konzistence českých lesnických subvencí s environmentálními cíli státní politiky / Czech forestry subsides coherence with environmental policy objectives

Kotecký, Vojtěch January 2015 (has links)
1 Vojtěch Kotecký Czech forestry subsides coherence with environmental policy objectives Abstract: Public bodies in the Czech Republic spend on average about CZK 1.2 billion (€ 44 million) a year on subsidy schemes in forestry. Subsidies are an important instrument of public policy; they also have major environmental consequences and may influence ability of forests to contribute towards ecosystem services. Consistency of forestry subsidies with the government's environmental policy goals in the Czech Republic is investigated in this thesis. Almost half of Czech subsidy budget is appropriated to schemes that have got an element of conflict with environmental policy goals incorporated in their design; thus, a range of environmentally harmful subsidies is potentially identified here. However, a number of schemes - and, in 27% of subsidy expenditure, even the same schemes, also contribute towards the same policy objectives. Farmland afforestation payments, contributing to the government's goal of forest expansion but shown in a statistical analysis to be focused primarily on regions with high forest cover, and involving a surplus of Norway spruce with a deficit of both European beech and silver fir, are an illustration of complex nature of forestry subsidies.
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Carbon, water, and energy dynamics of a temperate pine forest during the first decade since plantation on a former cropland

Chan, Felix January 2016 (has links)
This study presents the energy, carbon (C), and water exchange dynamics of a recently afforested temperate white pine (Pinus strobus L.) forest, established on former agricultural land in 2002, in southern Ontario, Canada during the initial thirteen years (2003–2015). Our observations show that the forest became a consistent sink of C after only 5 years of its establishment (ranging from 105 g C m–2 to 216 g C m–2 between 2008 to 2015), owing to sandy soils and low residual soil organic matter from prior agricultural activities. This region frequently experiences low precipitation (P) and soil moisture (VWC) limitations and/or heat stress in late summer, causing a reduction in net ecosystem productivity (NEP). Seasonal and annual dynamics of NEP showed reduced C uptake during years with heat and/or drought events (i.e. 2007 and 2012). In 2007, the impact of a seasonal drought was much more exacerbated when combined with a heatwave, resulting in a strong C source. Similarly, the inter-annual variability of evapotranspiration (ET) gradually increased with stand age (mean 370 mm yr–1) and water use efficiency (WUE) consistently increased (mean 2.65 g C kg–1 H2O). Quantum yield, α (0.019 to 0.045) and maximum photosynthetic capacity, Amax (4.37 to 33.6 µmol m–2s–1) increased steadily as the size and density of the canopy increased with stand age. Energy fluxes were influenced by canopy development as net radiation (Rn), latent heat (LE), and sensible heat (H) flux increased, while ground heat flux (G) peaked in 2007 and then gradually declined. Our analysis showed that daily C fluxes are primarily driven by Rn and temperature (Ts, Ta) which explained 47%, 61%, 52%, and 68% of the variability in gross ecosystem productivity (GEP), ecosystem respiration (RE), NEP, and ET. This study is a significant contribution to our understanding of the energy, C, and water dynamics of young planted conifer forests and controls on their growth and C uptake. Our findings demonstrate the potential of utilizing white pine as a means to sequester atmospheric CO2 in southern Ontario and other regions of North America with similar climate and site history. / Thesis / Master of Science (MSc)
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Mapping Elaeagnus Umbellata on Coal Surface Mines using Multitemporal Landsat Imagery

Oliphant, Adam J. 31 August 2015 (has links)
Invasive plant species threaten native plant communities and inhibit efforts to restore disturbed landscapes. Surface coal mines in the Appalachian Mountains are some of the most disturbed landscapes in North America. Moreover, there is not a comprehensive understanding of the land cover characteristics of post- mined lands in Appalachia. Better information on mined lands' vegetative cover and ecosystem recovery status is necessary for implementation of effective environmental management practices. The invasive autumn olive (Elaeagnus umbellata) is abundant on former coal surface mines, often outcompeting native trees due to its faster growth rate. The frequent revisit time and spatial and spectral resolution of Landsat satellites make Landsat imagery well suited for mapping and characterizing land cover and forest recovery on former coal surface mines. I performed a multitemporal classification using a random forest analysis to map autumn olive on former and current surface coal mines in southwest Virginia. Imagery from the Operational Land Imager on Landsat 8 were used as input data for the study. Calibration and validation data for use in model development were obtained using high-resolution aerial imagery. Results indicate that autumn olive cover is sufficiently dense to enable detection using Landsat imagery on approximately 12.6% of the current and former surface coal mines located in the study area that have been mined since the early 1980s. The classified map produced here had a user's and producer's accuracy of 85.3% and 78.6% respectively for the autumn olive coverage class. Overall accuracy in reference to an independent validation dataset was 96.8%. These results indicate that autumn olive growing on reclaimed coal mines in Virginia and elsewhere in the Appalachian coalfields can be mapped using Landsat imagery. Additionally, autumn olive occurrence is a significant landscape feature on former surface coal mines in the Virginia coalfields. / Master of Science
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Assessment of potential and impacts of afforestation in the Letaba catchment, Limpopo Province, South Africa

Mkwalo, Andile Churchill 07 1900 (has links)
The plantation forestry is economically a very important industry in South Africa because it promotes the upliftment of many rural South African communities. However, afforestation has significant impacts on water use and biodiversity in a catchment. Thus, understanding the effects of afforestation on water resources at the catchment level is fundamental for optimal water resource allocation, long-term sustainable use, development and conservation. Much of the Limpopo Province is climatically and physiographically suitable for plantation forestry but it only contains approximately 4.7 % of the total existing plantation area in South Africa. For example, the size of the Letaba Catchment of the Limpopo Province is 13 669 km² but only approximately 484 km² of it is currently afforested. This study aims to identify potential areas for further afforestation in the Letaba Catchment using the Water Resources Modelling Platform (WReMP) model to determine if afforestation can be expanded here to promote development in South Africa‟s poorest Province. / Geography / M. Sc. (Geography)

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