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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.
131

Vegetation Response to Restoration Treatments in a Former Pine Plantation in North Florida

Meyer, Ryan C. 01 January 2009 (has links)
As the human population in Florida continues to expand, development follows, and tree farms give way to homes and businesses. As parks are established, restoration of these semi-natural plantations may provide critical habitat for species conservation. This study evaluates vegetation response to restoration treatments at two study sites, formerly tree farms, now preserves in NE Florida. Treatments included thinning, clearing, or control (no treatment) within 10m^2 plots. Thinning reduced tree canopy to 20% (2-3 pines/plot) and removed all other vegetation; clearing treatments removed all biomass to bare soil; no herbicides were used. Within these plots richness and abundance was assessed by establishing two parallel transects and counting ramets on a bi-annual basis. Tree diameter at breast height (dbh) was also measured (cm). It was hypothesized that release of resources (thinning and clearing) would increase overall diversity (more so in graminoids and forbs), and encourage more robust tree growth versus control groups. Diversity ANOVA (Simpons & Shannon indices) showed significant differences due to survey date (p< 0.05) at the McGirts Creek site and a significant (p= 0.056) effect for the interaction term at the Tigers Point site. Tree dbh also increased at a significantly greater rate in thinned, versus control groups at the Tigers Point site (p= 0.03) perhaps due to higher initial tree density, but not at the McGirts Creek site (p= 0.85). Placing species into guilds revealed both sites reflected high levels of graminoids in cleared plots, which is consistent with early successional species (pioneer plants). McGirts followed hypothesis as forbs and graminoids were dominant in both thinned and cleared plots and the Tigers Point site had higher levels of vines and shrubs than expected. Restoration goals of increasing vegetative diversity, especially in r-selected species, and robust growth can be met by techniques used in this study.
132

Forest cover and water quality in tropical agricultural watersheds / Cobertura florestal e qualidade da água de microbacias agrícolas tropicais

Kaline de Mello 15 February 2017 (has links)
Tropical forests are under continual threat due to deforestation and forest fragmentation processes which are driven by the economic activities growth, mainly agriculture. Replacing forest with other land uses can cause severe impacts on river water quality, altering its physical, chemical and biological characteristics. The Atlantic Forest, in particular, had its original vegetation cover reduced to about 11%, wherein the crop lands expansion and urban sprawl still threatening this important ecosystem and the ecosystem services that it provides. In this sense, the main objective of this study was to investigate the relation between forest cover and water quality of tropical agricultural watersheds. For that, six experimental watersheds with different percentage of forest cover were selected in the Sarapuí River watershed, State of São Paulo, Brazil. Water samples were collected during a hydrologic year to obtain water quality parameters that represent impacts induced by anthropic activities. According to the percentage of forest cover, the watersheds were denominated as \"forested\", when they presented more than 55% of forest cover, and \"degraded\", with less than 35%. Multivariate statistical models were applied to identify differences between these two groups. In a second moment, the relation of land use/land cover within the watershed and within its respective riparian zone, represented in this study by the Permanent Preservation Areas (PPA), with water quality was compared through mixed models and redundancy analysis to identify the main factors that influenced water quality variability. Lastly, a watershed simulation modeling was applied to verify the impact of riparian forest restoration on water quality of the Sarapuí River watershed, wherein each experimental watershed was represented by a sub-watershed in the model. The results showed that the degraded watersheds presented higher values of solids, turbidity, nutrients and coliforms, besides presenting greater temporal data variability compared to forested watersheds. This variation is associated with the stream flow changes during the year. In general, forest cover was related to good water quality, while agriculture and urban areas were responsible for the water quality degradation. Pasture presented mixed impacts, but it was not generally correlated with poor water quality. The water quality parameters responded differently to the influence of land-use/land-cover patterns in the watershed and riparian zone, but the overall water quality is better explained by the landscape composition within the watershed. Nevertheless, the watershed simulation indicated that PPA restoration reduces the sediment and nutrients loading into the river. Thus, it is possible to conclude that tropical forest plays a fundamental role in the water resources conservation, reducing impacts of human activities in watersheds and the watershed management with forest restoration strategies for the entire watershed is critical for the maintenance of water quality to water supply, despite the importance of the riparian zone. / As florestas tropicais estão sob constante ameaça devido ao processo de desmatamento e fragmentação florestal impulsionado pelo crescimento das atividades econômicas, em especial, a agricultura. A substituição de áreas florestadas por outros usos do solo pode causar impactos severos na qualidade da água de rios, alterando suas características físicas, químicas e biológicas. A Mata Atlântica, em especial, teve sua cobertura original reduzida a cerca de 11%, sendo que a expansão de terras cultiváveis e urbanização ainda ameaçam esse importante ecossistema e os serviços ecossistêmicos prestados por ele. Nesse sentido, este estudo propôs investigar a relação da cobertura florestal com a qualidade da água de microbacias agrícolas tropicais. Para tanto, foram selecionadas seis microbacias experimentais com diferentes porcentagens de cobertura florestal na bacia do rio Sarapuí, Estado de São Paulo, Brasil, onde foram feitas coletas de amostras de água por um ano hidrológico para a obtenção de parâmetros que representassem alterações na água induzidas por atividades antrópicas. Inicialmente as microbacias foram classificadas em \"florestadas\" e \"degradadas\", e modelos estatísticos multivariados foram aplicados para identificar diferenças entre os grupos. Em um segundo momento comparou-se a relação do uso e cobertura do solo na microbacia e na Área de Preservação Permanente (APP) com a qualidade da água utilizando-se modelos mistos e análise de redundância para identificar os principais fatores que influenciam a variabilidade da qualidade da água. Por último foi gerado um modelo hidrológico para simular o impacto da restauração da floresta ripária na qualidade da água da bacia do rio Sarapuí onde cada microbacia experimental desse estudo foi representada por uma sub-bacia do modelo. Os resultados mostram que as microbacias degradadas apresentam valores maiores de sólidos, turbidez, nutrientes e coliformes. Além disso, apresentam maior variabilidade temporal dos dados em relação às microbacias florestadas associada às alterações da vazão do rio. Em geral, a cobertura florestal foi relacionada à boa qualidade da água, enquanto que agricultura e ocupação urbana foram os usos do solo responsáveis pela degradação da qualidade da água. O uso pastagem apresentou impactos mistos, porém no geral não foi correlacionado à qualidade da água ruim. Os parâmetros de qualidade da água responderam de forma diferente quanto à influência dos padrões de uso e cobertura do solo na microbacia e na APP, porém, considerando-se todos parâmetros em conjunto, a qualidade da água é melhor explicada pela composição da paisagem da microbacia. Ainda assim, a simulação do modelo indicou que a restauração das APPs reduz a carga de sedimentos e nutrientes para o rio. Com isso, conclui-se que a floresta tropical tem papel fundamental na conservação dos recursos hídricos, reduzindo impactos das atividades humanas exercidas nas microbacias e que, apesar da importância das APPs na redução de poluentes para o rio, o manejo de bacias com estratégias de restauração florestal para toda a microbacia é extremamente importante para a manutenção da qualidade da água para abastecimento.
133

Working Backwards: Enhancing Forest Restoration by Reversing Effects of Surface Mine Reclamation on Soil Bulk Density and Soil Chemistry

Back, Michael Patrick 18 May 2021 (has links)
No description available.
134

From deforestation to forest recovery: perspectives for the Amazon under the rule of the Brazilian Forest Code

de Barros Viana Hissa, Leticia 26 May 2021 (has links)
Die anhaltende Entwaldung tropischer Regenwälder und die damit einhergehenden sozialen und ökologischen Folgen finden zunehmend Beachtung nationaler Regierungen und zivilgesellschaftlicher Akteure, die Initiativen zur Verringerung der Entwaldung und Strategien zum Schutz von Lebensräumen und Artenvielfalt entwickelt haben. Die Waldrestaurierung, d.h. die Wiederherstellung von Waldökosystemen, stellt hierbei, neben der Verringerung der Entwaldung, ein entscheidendes Ziel dar. Brasilien spielt in diesem Zusammenhang eine entscheidende Rolle. Der Großteildes Amazonas-Regenwaldes, der größte zusammenhängende tropische Regenwald der Welt, liegt auf brasilianischem Gebiet. Nahezu 18% des brasilianischen Regenwaldes sind bereits gerodet. Landspekulation, Bergbau, und Landwirtschaft stellen die stärkste Bedrohung für die Existenz des Regenwaldes dar. Im Rahmen des Pariser Abkommens hat sich Brasilien dazu verpflichtet die Netto-Entwaldung bis 2030 zu stoppen und 12 Millionen Hektar Waldökosysteme wiederherzustellen. Eine zentrale Rolle für die Umsetzung der Verpflichtung kommt dem brasilianischen Waldschutzgesetz (BFC) zu, der wichtigsten brasilianischen Umweltgesetzgebung, die die Rahmenbedingungen für die Landnutzung auf privatem Landbesitz regelt. Im brasilianischen Amazon verlangt das BFC den Schutz von 80% der natürlichen Vegetation, als sogenanntes Legal Reserves (LRs). In der neusten Gesetzesversion von 2012 wurde erstmals der Umgang mit denjenigen Landbesitzern festgelegt, die den Gesetzesvorgaben nicht entsprechen. Es wird erwartet, dass die Umsetzung des neuen BFCs auf der einen Seite den Schutz der Wälder in den LRs gewährleistet und auf der andern Seite, unter Mitwirkung der Landbesitzer, zu ein großflächige Waldrestaurierung führt. Vor diesem Hintergrund ist das Ziel dieser Dissertation die Potenziale des BFC für den Schutz der Ur- und den nachwachsenden Wäldern zu ermitteln. Im Speziellen habe ich in der vorliegenden Dissertation (i) die Raum-Zeitlichen Veränderungen der Waldflächen im Einflussbereich der Bundesstraße BR-163, zwischen Cuiabá und Santarém, analysiert; (ii) das Potenzial der BFC für den Schutz der des Regenwaldes und für die Waldrestaurierung bewertet; und (iii) prioritäre Gebiete für ein großflächige Waldrestaurierung, unter Einbezug von Kosten, Biodiversität und Kohlenstoffspeicherung, identifiziert. Die Ergebnisse zeigen, dass ein Großteil der massiven Entwaldung in der Region zwischen Cuiabá und Santarém auf privaten Grundstücken stattfand. Dies lässt auf eine weitverbreitete Nichteinhaltung des BFCs schließen. Hohe Netto-Entwaldungsraten und eine rückläufige Verbreitung nachwachsenden Waldes deutet darauf hin, dass die Region weit von einer Trendwende von Netto-Waldverlust, zu Netto-Waldzuwachs entfernt ist. Um eine Ausbreitung der Wälder voranzutreiben, ist es daher notwendig, das Management der Ur- und nachwachsenden Wälder zu verbessern. Die Ergebnisse dieser Dissertation zeigen, dass mehr als 6 Millionen Hektar der derzeitigen Waldregeneration geschützt und ein Drittel der LR-Defizite ausgeglichen werden könnten, wenn die nachwachsenden Wälder in die Schutzzonen der LRs einbezogen werden. Die künftige Regulierung der BFC-Ausgleichsmechanismen wird einen entscheidenden Effekt auf die Waldrestaurierung und den Schutz der Urwälder haben. Die Analyse möglicher Regulierungs-Szenarien hat deutliche Variation zwischen prioritären Gebieten für die Waldrestaurierung in Mato Grosso gezeigt. Die Ergebnisse zeigen, dass die Waldrestaurierung auf privaten Grundstücken entscheidend für den Schutz von Biodiversität ist. Demgegenüber zeigt sich die Wiederherstellung von Waldökosystemen auf öffentlichem Land kostengünstiger und effektiver für die Kohlenstoffspeicherung. Die Ergebnisse demonstrieren die Relevanz detaillierter räumlicher Informationen zu Landbesitz und Landnutzungsänderungen, um die Auswirkungen von neuen rechtlichen Rahmenbedingungen für den Waldschutz und die Waldrestaurierung in tropischen Gebieten zu untersuchen. Die Schätzungen der derzeit nachwachsenden Waldflache, und dessen Schutzstatus, sind entscheidend um die nationalen Ziele der Waldrestaurierung zu erreichen. Die Ergebnisse verdeutlichen, dass ein besseres Management von nachwachsenden Waldökosystemen durch Bundes- und Landesgesetze notwendig ist, und neue Strategien und Mechanismen, die den Schutz nachwachsenden Wäldern sicherstellen, erarbeitet werden müssen. / Continued tropical forests decline has drawn concerted attention by governments and distinct sectors of the civil society, which have responded with anti-deforestation policies and conservation strategies. Alongside conservation, large-scale forest restoration is crucial for counteracting the negative impacts of deforestation on socio-ecological processes. In this context, Brazil plays a pivotal role. Most of the Amazon, the largest continuous tropical forest in the world, lies within the Brazilian territory. Nearly 18% of the Brazilian Amazon forest cover was already lost, and land speculation, mining, and agricultural expansion continue to threaten the forest. Therefore, cutting back land use change emissions is a major pillar of Brazil’s commitment to the Paris Agreement, which includes the plan to achieve zero net deforestation in the Amazon and restore 12Mha of forests countrywide by 2030. In this thesis I focused on the Brazilian Forest Code (BFC), the flagship environmental legislation governing land use in private lands of Brazil. In forestlands of the Amazon biome, the BFC requires the protection of 80% of the native vegetation as Legal Reserves (LRs). The latest version of the law, from 2012, also established the compliance conditions for past law offenders. Particularly, there are high expectations that the enforcement of the BFC will secure the protection of forests in LRs, and drive large-scale forest restoration. Therefore, my overall goal was to advance the knowledge about the potential of the BFC enforcement for the conservation of old- and regrowing forests in the Brazilian Amazon. Specifically, I (i) investigated the spatio-temporal patterns of net forest cover change for the influence area of the Cuiabá-Santarém highway, crossing the federal states of Pará and Mato Grosso in the Brazilian Amazon; (ii) evaluated the potential of the BFC enforcement for the protection of old and regrowing forests in the Brazilian Amazon, and estimated the contribution of regrowing forests for LRs demarcation; and (iii) applied a multicriteria analysis to map priority areas for large-scale forest restoration in private and public lands of Mato Grosso, contrasting the costs of restoration with the gains for biodiversity and carbon enhancement. Results show that the Cuiabá-Santarém focus region accumulated substantial deforestation, most of which on private lands, indicating a widespread non-compliance to the BFC. High net deforestation rates and decreasing prevalence of forest regrowth on deforested lands, indicates that this region is not near experiencing a turnaround from net forest losses to net forest gains. Hence, to promote forest expansion, it will be necessary to improve old- and regrowing forests governance. In this regard, results showed that if regrowing forests are included in LRs demarcation, over 6Mha of ongoing forest regeneration could be protected, and one third of LRs deficits could be offset. Also, the future regulation of BFC compensation mechanisms will be key for determining the potential of the law for promoting restoration and old-growth forests protection additionality. Finally, a substantial variation in the spatial distribution of priority areas for forest restoration was identified across Mato Grosso, and for different scenarios. Private properties were key to enhance intensively deforested habitats, while restoration in public lands was more effective in reducing restoration costs and mitigating carbon. The findings of this thesis demonstrate the importance of detailed spatial information on land tenure and land use change in tropical areas, to support spatial planning, and address the potential of legal frameworks for promoting forest conservation and restoration. The estimates of legal protection of current regrowing forests have strong implications for Brazil’s restoration targets. They call for an improved treatment of second-growth forests by federal and state legislations, and the creation of policy and mechanisms able to secure the protection of high-value regrowing forests.
135

The Erosion of Coastal Sediment and Regeneration of Rhizophora mangle Following Anthropogenic Disturbance on Turneffe Atoll, Belize

Hayden, Heather Lyn 28 May 2015 (has links)
As communities and managers become aware of the long-term impacts of mangrove loss, estimated at 1-2% per year, interest in sediment erosion and mangrove rehabilitation has increased substantially. In this thesis project I 1) examine erosion rates within coastal fringing Rhizophora mangle ecosystems following mangrove clearing and compare these rates to accretion rates in intact mangroves; and 2) investigate the abiotic factors influencing mangrove seedling survival and regeneration of naturally colonizing R. mangle, in historic mangrove habitat after anthropogenic clearing. Differences in erosion were compared between patches of open-coast intact and anthropogenically cleared R. mangle to quantify the sediment trapping function provided by mangroves and its loss following clearing over a 24 month period. Growth rates of mangrove seedlings in intact forest were compared to seedlings in cleared areas. Seedling growth indicators were measured on 100 seedlings at five sites (50 in the intact and 50 in the cleared areas). To examine the limiting factors on seedling growth rates, nutrient addition and wave protection treatments were applied to seedlings in three disturbed areas. Sites within intact mangroves had sediment accretion (M= +3.83 mm) while areas cleared of mangroves had sediment erosion (M= -7.30 mm). Seedling growth (height) over the 2 year study period significantly differed between intact mangrove (M = 15.6 cm) and cleared (M = 10.24 cm) areas. Seedling mortality from the cleared areas (31%) differed from the intact areas (13%). Average seedling growth (height) was: greater with both nutrient/wave (M = 18.4 cm) and nutrient (M = 17.65 cm) treatments compared to controls (M = 10.8 cm), which suggests that providing nutrients and/or wave protection result in growth outputs comparable to seedlings found in intact mangroves. This study may prove to be useful in identifying areas that are most vulnerable to erosion following mangrove removal and ideal location of restoration following mangrove removal. Areas cleared of mangroves can lead to intensified erosion in areas where fringing reefs are not continuous. When managers are determining areas to focus resources for restoration, focusing on areas with nutrient rich habitat may result in higher survival rates and growth outputs.
136

Evaluation of a Restoration Approach After One Century – Effects of Admixed European Beech on the Natural Regeneration Potential and Humus Condition in Spruce Stands

Axer, Maximilian, Kluckow, Fabian, Wagner, Sven 02 February 2024 (has links)
About 100 years ago, groups of European beech were reintroduced into Norway spruce stands in some parts of Germany as a restoration approach. The aim of this approach was to maintain or rehabilitate the ecological function of soil fertility and the regeneration option of beech for the next generation. The effect of beech groups on surrounding spruce stands was studied in the Ore Mountains by recording natural regeneration of beech and humus layer thickness and form. Point pattern statistics were used to analyse the spread of beech regeneration and to determine factors influencing its establishment. It was found that the density of regeneration decreases with increasing distance from the beech group. However, beech regeneration was found up to distances of 69 m. Furthermore, it becomes evident that PAR radiation (maximum regeneration densities at PAR values of 35 W/m²) and fencing (3.41 times higher regeneration density compared to unfenced areas) against deer have a positive influence on beech regeneration density. Ordered categorical models were used to model humus form and non-linear models were used to model humus layer thickness. It could be proven that the most bioactive humus forms and lowest humus layer thicknesses were found within the beech group. With increasing distance to the beech group, the total humus layer thickness and the proportion of mormoder in the spruce stand increased. The positive influence of the beech group on the humus composition extends to about 40 m from the centre of the beech group. Due to the former arrangement of the beech groups in the terrain, the effects can also extend to the spruce stands in between. The hypotheses on the restoration approach of reintroducing groups of beech into spruce stands formulated by foresters 100 years ago can thus be confirmed. For future restoration approaches of spruce stands, groupwise mixtures of beech should be established with a distance of 40–50 m.
137

Relações entre a estrutura da paisagem e a diversidade da vegetação em florestas secundárias na região das cuestas, Charqueada e São Pedro, São Paulo / Relationships between landscape structure and vegetation diversity in secondary forests in the cuestas region, Charqueada and São Pedro, São Paulo

Santos, Marcelo Éric de Almeida 14 May 2019 (has links)
O estado atual do desmatamento de florestas primárias e o restabelecimento de florestas secundárias no Brasil variam de acordo com a região do país. Enquanto alguns domínios têm perdido grandes extensões de cobertura original, como a Floresta Amazônica e o Cerrado, outros têm registrado um aumento na área ocupada por florestas, como é o caso da Mata Atlântica no estado de São Paulo. O processo de regeneração de florestas secundárias tem sido registrado nos últimos 30 anos, devido ao abandono de pastagens e iniciativas de restauração florestal. Dessa forma, o objetivo principal deste estudo foi investigar se florestas secundárias regenerando em pastagens abandonadas diferem em relação à composição e diversidade de espécies florestais sob duas condições distintas de característica da paisagem: áreas com elevada proporção de cobertura florestal no entorno (>30%) e áreas com baixa proporção de cobertura florestal no entorno (<10%). Com base em imagens do ano de 1972, foram delimitadas as áreas ocupadas por remanescentes antigos de vegetação, com idade superior a quarenta anos. Após, o mapa de vegetação produzido com estas imagens foi sobreposto a um mapa de cobertura da terra de 2018, para identificar a expansão e a diminuição da vegetação. Com base nestes dois mapas, nós avaliamos as modificações na estrutura da paisagem, durante este período de 46 anos. Depois disso, nós selecionamos oito áreas, sendo quatro estruturalmente conectadas, com elevada proporção de cobertura florestal no entorno e quatro estruturalmente isoladas, com baixa cobertura florestal no entorno. Em cada área nós avaliamos a composição, riqueza de espécies, densidade, síndrome de dispersão, biomassa acima do solo, diversidade e equabilidade. Contrário ao que esperávamos, nossos resultados demonstraram que as plantas do estrato inferior em áreas com baixa cobertura florestal no entorno tiveram maior proporção de espécies dispersas por animais do que nas áreas com alta cobertura florestal no entorno, bem como também foram encontradas diferenças na composição de espécies da comunidade do estrato inferior. Nossas descobertas indicam que as condições estruturais da paisagem podem influenciar grupos funcionais da comunidade do estrato inferior na região das cuestas, tornando o contexto da paisagem um parâmetro essencial a ser considerado na conservação e restauração da biodiversidade, especialmente em paisagens com elevado grau de fragmentação. / The current state of deforestation of old-growth forests and the restablishmet of secondary forests in Brazil varies according to the region. While some biomes have lost many extensions of original cover, such as Amazon forest and Cerrado, others have registered an increasing in the area occupied by forests, as the case of the Atlantic forest in São Paulo state. The regeneration process of secondary forests has been registered for the last 30 years, due to the abandonment of pastures and initiatives of seedling plantings. Therefore, the main goal of this study was to investigate whether secondary forests regenerating in abandoned pastures differ in relation to the composition and diversity of forest species under two different landscape characteristics: connected areas, with high proportion of forest cover around (>30%) and isolated areas, with low proportion of forest cover around (<10%). Based on images of 1972, old-forest remnants were delimited. After, the vegetation map produced for 1972 was overlapped to a land cover map of 2018 to record the expansion and decrease of vegetation. Based on these two maps, we evaluated the modifications in the landscape structure, during the 46-years period. After that, we selected eight areas, being four structurally connected and four, structurally isolated. At each area we evaluated composition, species richness, diversity, equability, density, dispersal syndrome and aboveground biomass. Contrary to expectations, our results showed that regenerating plants in isolated areas have higher proportion of animal-dispersed seed species than connected areas. We also found differences in the plant composition of regenerating communities between connected and isolated areas. Our findings indicate that structural conditions of the landscape can influence functional groups of the regenerating plants in the cuestas region, making the landscape context an essential parameter to be considered in conservation and restoration plans, especially in highly fragmented landscapes.
138

O papel dos remanescentes florestais na manutenção da qualidade da água em microbacias agrícolas / The role of forest remnants in the maintenance of water quality in agricultural watersheds

Carla Cristina Cassiano 05 February 2013 (has links)
As florestas se apresentam como a melhor cobertura do solo para a manutenção da qualidade natural das águas superficiais, proporcionando serviços ecossistêmicos de regulação e provisão desse recurso. A conversão de florestas em usos antrópicos tende a reduzir a qualidade da água, devido ao aporte de nutrientes e sedimentos provenientes da movimentação e manejo do solo. A presença de vegetação na área ripária pode reduzir esses efeitos, através da prestação de alguns serviços de proteção dos corpos d\'água. O objetivo deste trabalho foi detectar a influência da mata ciliar na composição físico-química da água em microbacias agrícolas. O trabalho foi dividido em duas partes, a primeira buscou avaliar o estado da vegetação florestal na área de estudo e o seu potencial na prestação de serviços e a segunda parte avaliar o efeito da vegetação em parâmetros físico-químicos da água. As unidades de estudo foram definidas na bacia do rio Corumbataí, a partir do mapeamento do uso do solo do ano de 2000 pelo método de amostragem adaptativa, onde as unidades deveriam apresentar um mínimo de 70% de matriz e 10% de cobertura florestal. Foram selecionadas seis unidades de 16 km2, três unidades com matriz de pasto e três unidades com matriz de cana-de-açúcar. Com as unidades definidas foram realizados os mapeamentos por fotointerpretação para cinco datas (1962, 1978, 1995, 2000 e 2008), a partir desse mapeamento foi possível calcular as mudanças do uso do solo e índices para os fragmentos florestais identificando sua trajetória. Também foram utilizados mapas de solos e geologia, e realizado o mapeamento do relevo para reconhecimento dos aspectos físicos e químicos do terreno. Sete microbacias, de primeira a segunda ordem de drenagem, foram selecionadas e tiveram amostras de água coletadas durante um ano, quinzenalmente, para análise dos parâmetros físico-químicos da água. As diferenças na ocupação do uso do solo e na trajetória dos fragmentos florestais entre as matrizes foram avaliadas através da Análise de Variância e as diferenças entre as variáveis da água foram avaliadas através do teste nãoparamétrico de Wilcoxon-Mann-Whitney. Os resultados mostraram que a vegetação florestal nas unidades tem aumentado nos últimos anos, dando indícios ao inicio de uma fase de regeneração, conhecida como a segunda fase da transição florestal, porém apenas estudos futuros poderão confirmar essa análise. As matrizes apresentam similaridade em relação à área ocupada por floresta, porém a trajetória dessas florestas foi diferente. O potencial de prestação de serviços por essas florestas em relação à proteção dos riachos é relativamente baixo, onde através da metodologia utilizada foi possível observar que apenas 1/3 da vegetação florestal apresenta-se adequada para a prestação de serviços. A cana-de-açúcar promove o aumento de nitrogênio no riacho, enquanto a pastagem apresenta concentração maior de carbono orgânico dissolvido. A floresta ripária é essencial para a manutenção do ecossistema aquático e está contribuindo para o aumento da concentração de alguns nutrientes na água. / Forests present themselves as the best land use for maintaining the quality of natural surface water, providing ecosystem services of provision and regulation for this resource. The conversion of forests to anthropogenic uses tends to reduce the quality of waters due the nutrients and sediment inputs from moving and soil management. The presence of vegetation in the riparian area can reduce these effects by providing some services as the protection of water bodies. The aim of this study was to detect the influence of riparian vegetation on water physico-chemical composition in agricultural watersheds. The work was divided into two parts, the first sought to evaluate the state of the forest vegetation in the study area and its potential in providing services and the second part to assess the effect of vegetation on physico-chemical parameters of the water. The study units were defined in Corumbataí river basin, from a mapping of the land use in 2000 by adaptive sampling method, where the units should have a minimum 70% matrix and 10% forest cover. Were selected six units of 16 km2, three units with pasture matrix and three units with sugar cane matrix. With the units defined mappings were performed by photointerpretation for five dates (1962, 1978, 1995, 2000 and 2008), from this mapping was possible to calculate the changes in land use and some indices for forest fragments. Were also used maps of soils and geology, and the mapping of relief for recognition of physical and chemical aspects of the terrain. Seven watersheds, from first to second order, were selected and water samples were collected during one year, biweekly, for the analysis of physico-chemical parameters of the water. Differences in occupation of land use and the trajectory of forest fragments between matrices were evaluated using analysis of variance and differences between water variables were assessed using the nonparametric Wilcoxon-Mann-Whitney test. The results showed that the forest vegetation cover has increased in recent years, giving evidence the beginning of a regeneration phase, known as the second stage of forest transition, but only future studies can confirm this analysis. The matrices exhibit similarity to the area occupied by forest, however, the trajectories of these forests were different. The potential of services by these forests in relation to protection of streams is relatively low, which through the methodology it was observed that only 1/3 of the forest has been considered appropriate for the provision of services. The sugar cane promotes the increase of nitrogen in the stream, while the pasture has higher concentration of dissolved organic carbon. The riparian forest is essential to the maintenance of the aquatic ecosystem. The forests are contributing to the increase in the concentration of some nutrients in the water.
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Efeito dos tratos culturais e qualidade de mudas na restauração florestal de matas ciliares do Rio Tietê em Borborema, SP / Effect the cultural practices and seedlings quality in forest restoration of the Tiete River\'s riparian forests in Borborema, SP

Pereira, Daniela da Silva 17 September 2012 (has links)
A restauração florestal em matas ciliares é de suma importância para os processos de recuperação de áreas degradadas e conectividade da flora e fauna. O presente experimento foi instalado às margens do reservatório de Borborema - SP, com o objetivo de averiguar o acúmulo de biomassa de trinta espécies arbóreas nativas frente a dois sistemas silviculturais e dois tipos de recipientes de produção de mudas. O ensaio foi instalado em duas áreas com umidade de solo distintas, sendo uma mais seca, sem encharcamento mesmo em períodos chuvosos, outra mais úmida, com encharcamento. Os sistemas de manejo testados foram: i) convencional e operacionalmente utilizado pela empresa AES-Tietê; e ii) potencial, com maior nutrição e maior controle de mato-competição. Os recipientes de produção de mudas testados foram o tubete pequeno, com 56 cm3; e tubete grande com 290 cm3. O estudo foi instalado em fatorial 2x2, com os fatores Manejo e Tubete e dois níveis de cada fator (potencial e convencional, e tubete pequeno e grande) com quatro repetições na área seca. Não ocorreu interação entre os fatores estudados. Na área seca, o tratamento que utilizou tubete grande e manejo potencial apresentou diâmetro e altura 30% superiores que o tratamento que utilizou tubete pequeno e manejo convencional, e uma superioridade em 70% no Índice de Área Foliar e 62% no acúmulo de biomassa aos dois anos. O tubete grande apresentou sobrevivência de plantio 13% superior ao tubete pequeno e ganho em biomassa média das mudas de 43%. O manejo potencial apresentou área basal superior ao manejo convencional (6,23 versus 4,09m2ha-1) e IAF superior (1,28 versus 0,58 m2m- 2). Na área úmida, as zonas de alagamento baixo, médio e total apresentaram área basal decrescentes de 4,4 m2 ha-1, 2,6 m2 ha-1 e 0,9 m2 ha-1. Com esses resultados é possível concluir que as espécies nativas possuem capacidade de melhor desempenho quando produzidas em tubetes maiores e sob sistema silvicultural mais intensivo e que o alagamento (falta de aeração da raiz) é um estresse ambiental que requer melhor compreensão por ser altamente limitante à restauração com as espécies tradicionais. / Riparian forest restoration is extremely important for the processes of degraded areas restoration and connectivity of flora and fauna. This study was established on the Reservoirs of the Borborema Lake - SP, with the purpose to determine the biomass accumulation of thirty tree species native to two silvicultural systems and two sizes of hard plastic tubes for seedling production. This trial was conducted in two areas with different soil moisture, a more drought, without flooding even during rainy periods, and another more humid, with frequent flooding. The following silvicultural systems were tested: i) traditional, one who is operationally used by the AES Tiete company; ii) potential, with greater nutrition and greater weed control. The containers for seedlings production tested were small hard plastic tubes with 56 cm3, and large hard plastic tubes with 290 cm3. The study was carried out in a factorial 22, with factors such as silvicultural systems and sizes of recipients, being two levels of each factor (potential, traditional, small and large hard plastic tubes) and four replications in a dry area. There was no interaction between the factors studied. In dry area the treatment that used large hard plastic tubes and potential silvicultural system showed diameter and height 30% higher than the treatment that used small hard plastic tubes and traditional silvicultural system, and also a superiority of 70% for the Leaf Area Index and 62% for biomass to two years. The seedlings produced in large hard plastic tubes showed survival at planting 13% higher than those grown in small hard plastic tubes. Was also observed that the mean biomass of seedlings was 43% higher for treatment of large tubes. Potential silvicultural system showed basal area greater than the traditional silvicultural system (6.23 vs. 4.09 m2 ha-1) and higher LAI (1.28 vs. 0.58 m2 m-2). In the wetlands, the zones of low, medium and high flooding frequency showed decreasing basal area of 4.4 m2 ha-1, 2.6 m2 ha-1 and 0.9 m2 ha-1. With these results we can conclude that native species have a higher performance when produced in large hard plastic tubes and under more intensive silvicultural system and flooding (lack of aeration of the root) is an environmental stress that requires better understanding because it is factor highly limiting for the restoration with the traditional species.
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O papel dos remanescentes florestais na manutenção da qualidade da água em microbacias agrícolas / The role of forest remnants in the maintenance of water quality in agricultural watersheds

Cassiano, Carla Cristina 05 February 2013 (has links)
As florestas se apresentam como a melhor cobertura do solo para a manutenção da qualidade natural das águas superficiais, proporcionando serviços ecossistêmicos de regulação e provisão desse recurso. A conversão de florestas em usos antrópicos tende a reduzir a qualidade da água, devido ao aporte de nutrientes e sedimentos provenientes da movimentação e manejo do solo. A presença de vegetação na área ripária pode reduzir esses efeitos, através da prestação de alguns serviços de proteção dos corpos d\'água. O objetivo deste trabalho foi detectar a influência da mata ciliar na composição físico-química da água em microbacias agrícolas. O trabalho foi dividido em duas partes, a primeira buscou avaliar o estado da vegetação florestal na área de estudo e o seu potencial na prestação de serviços e a segunda parte avaliar o efeito da vegetação em parâmetros físico-químicos da água. As unidades de estudo foram definidas na bacia do rio Corumbataí, a partir do mapeamento do uso do solo do ano de 2000 pelo método de amostragem adaptativa, onde as unidades deveriam apresentar um mínimo de 70% de matriz e 10% de cobertura florestal. Foram selecionadas seis unidades de 16 km2, três unidades com matriz de pasto e três unidades com matriz de cana-de-açúcar. Com as unidades definidas foram realizados os mapeamentos por fotointerpretação para cinco datas (1962, 1978, 1995, 2000 e 2008), a partir desse mapeamento foi possível calcular as mudanças do uso do solo e índices para os fragmentos florestais identificando sua trajetória. Também foram utilizados mapas de solos e geologia, e realizado o mapeamento do relevo para reconhecimento dos aspectos físicos e químicos do terreno. Sete microbacias, de primeira a segunda ordem de drenagem, foram selecionadas e tiveram amostras de água coletadas durante um ano, quinzenalmente, para análise dos parâmetros físico-químicos da água. As diferenças na ocupação do uso do solo e na trajetória dos fragmentos florestais entre as matrizes foram avaliadas através da Análise de Variância e as diferenças entre as variáveis da água foram avaliadas através do teste nãoparamétrico de Wilcoxon-Mann-Whitney. Os resultados mostraram que a vegetação florestal nas unidades tem aumentado nos últimos anos, dando indícios ao inicio de uma fase de regeneração, conhecida como a segunda fase da transição florestal, porém apenas estudos futuros poderão confirmar essa análise. As matrizes apresentam similaridade em relação à área ocupada por floresta, porém a trajetória dessas florestas foi diferente. O potencial de prestação de serviços por essas florestas em relação à proteção dos riachos é relativamente baixo, onde através da metodologia utilizada foi possível observar que apenas 1/3 da vegetação florestal apresenta-se adequada para a prestação de serviços. A cana-de-açúcar promove o aumento de nitrogênio no riacho, enquanto a pastagem apresenta concentração maior de carbono orgânico dissolvido. A floresta ripária é essencial para a manutenção do ecossistema aquático e está contribuindo para o aumento da concentração de alguns nutrientes na água. / Forests present themselves as the best land use for maintaining the quality of natural surface water, providing ecosystem services of provision and regulation for this resource. The conversion of forests to anthropogenic uses tends to reduce the quality of waters due the nutrients and sediment inputs from moving and soil management. The presence of vegetation in the riparian area can reduce these effects by providing some services as the protection of water bodies. The aim of this study was to detect the influence of riparian vegetation on water physico-chemical composition in agricultural watersheds. The work was divided into two parts, the first sought to evaluate the state of the forest vegetation in the study area and its potential in providing services and the second part to assess the effect of vegetation on physico-chemical parameters of the water. The study units were defined in Corumbataí river basin, from a mapping of the land use in 2000 by adaptive sampling method, where the units should have a minimum 70% matrix and 10% forest cover. Were selected six units of 16 km2, three units with pasture matrix and three units with sugar cane matrix. With the units defined mappings were performed by photointerpretation for five dates (1962, 1978, 1995, 2000 and 2008), from this mapping was possible to calculate the changes in land use and some indices for forest fragments. Were also used maps of soils and geology, and the mapping of relief for recognition of physical and chemical aspects of the terrain. Seven watersheds, from first to second order, were selected and water samples were collected during one year, biweekly, for the analysis of physico-chemical parameters of the water. Differences in occupation of land use and the trajectory of forest fragments between matrices were evaluated using analysis of variance and differences between water variables were assessed using the nonparametric Wilcoxon-Mann-Whitney test. The results showed that the forest vegetation cover has increased in recent years, giving evidence the beginning of a regeneration phase, known as the second stage of forest transition, but only future studies can confirm this analysis. The matrices exhibit similarity to the area occupied by forest, however, the trajectories of these forests were different. The potential of services by these forests in relation to protection of streams is relatively low, which through the methodology it was observed that only 1/3 of the forest has been considered appropriate for the provision of services. The sugar cane promotes the increase of nitrogen in the stream, while the pasture has higher concentration of dissolved organic carbon. The riparian forest is essential to the maintenance of the aquatic ecosystem. The forests are contributing to the increase in the concentration of some nutrients in the water.

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