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Fluxo de gases de efeito estufa em eolos do Pampa Gaúcho sob silviculturaGodoi, Stefânia Guedes de 12 December 2012 (has links)
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Previous issue date: 2012-12-12 / A região do Pampa Gaúcho está passando por modificação do tipo de uso do solo, com a inserção da silvicultura em solos de pastagens ou agricultura. No entanto, pouco se conhece sobre o impacto que tal mudança implica no fluxo dos Gases de Efeito Estufa (GEE) nessa
região, especialmente em relação aos fluxos de metano (CH 4 ) e óxido nitroso (N 2 O) do solo.
Este estudo teve como objetivo principal avaliar a inserção da silvicultura, com Acacia mearnsii De Wild e Eucalyptus saligna, em áreas de campo nativo e o seu efeito no fluxo CH 4 e N 2 O do solo, e determinar os principais fatores de solo que governam os fluxos destes gases. Dois experimentos foram realizados durante o período de um ano, em povoamentos de Acacia mearnsii De Wild avaliando quatro tratamentos: Acácia (AM), Acácia com retirada manual de serrapilheira (A-s), Acácia recém colhida (AC) e campo nativo (CN); e de Eucalyptus saligna avaliando cinco tratamentos: Eucalipto com quatro anos (E4), Eucalipto com quatro anos com retirada manual da serrapilheira (E4-s), Eucalipto com dois anos (E2), Mata Nativa (MN) e
Campo Nativo (CN), utilizando o campo nativo como tratamento de referência. As amostras de ar foram coletadas quinzenalmente pelo método de câmaras estáticas e os teores dos gases foram determinados por cromatografia gasosa. Em cada evento de amostragem de ar, foram avaliados a umidade e os teores de nitrogênio mineral do solo, coletada a serrapilheira e monitorada a temperatura do solo e do ar dentro da câmara. A inserção tanto do eucalipto como de acácia não alterou significativamente os fluxos de CH 4 e N 2 O do solo em relação ao campo nativo adjacente a cada floresta. Os fluxos de N 2 O foram geralmente baixos, com a maioria dos valores entre –5 e 30 μg N m -2 h -1 , provavelmente favorecidas pela baixa precipitação do período avaliado e dos baixos teores de nitrogênio mineral do solo. Houve predomínio de oxidação de CH 4 nos solos sob silvicultura no período avaliado, em magnitude
similar ao campo nativo. O solo sob eucalipto com dois anos tendeu a emitir mais N 2 O do que com quatro anos. A colheita da acácia promoveu aumento da emissão de N 2 O, provavelmente decorrente da maior disponibilidade de nitrogênio mineral no solo para os processos de nitrificação e desnitrificação. Em relação ao CH 4 , a maior emissão coincidiu com os períodos de temperatura do solo mais elevada, o que é coerente com o aumento da atividade biológica,
principalmente em áreas com menor cobertura vegetal. Os teores de carbono orgânico total (COT) e nitrogênio total (NT) do solo sob eucalipto e acácia não diferiram significativamente
do campo nativo para a ampla maioria das camadas avaliadas. Somado aos baixos fluxos de CH 4 e N 2 O da silvicultura, o sequestro de carbono via biomassa vegetal e produtos madeireiros sugerem que a mudança de uso do solo com inserção de silvicultura seja uma
opção efetiva para a mitigação dos GEE e aumento do sequestro de carbono em áreas da região do Pampa Gaúcho. / The soil use in the region of the Pampa Gaúcho has been modified by of forestation in soils
previously used for agriculture or grazing. However, little is known about the impact of this
change on greenhouse gases (GHG) fluxes in the soil in that region, mainly regarded to the
methane (CH 4 ) and nitrous oxide (N 2 O). This study aimed to evaluate the effect of the
conversion of native grassland to forestry, with Acacia mearnsii De Wild and Eucalyptus
saligna, in the Pampa Gaúcho on the soil CH 4 and N 2 O fluxes, besides determining the soil
variables that govern these fluxes. Two experiments were conducted for one year, in
plantations of Acacia mearnsii De Wild evaluating four treatments: Acacia (AM), Acacia with
manual litter removal (A-s), Acacia recently harvested (AH) and native grassland (NG); and
Eucalyptus saligna evaluating five treatments: four–year Eucalyptus plantation (E4), four–
year Eucalyptus plantation with manual litter removal (E4-l), two–year Eucalyptus plantation
(E2), Native forest (NF) and Native grassland (NG), using the native grassland as reference
treatment. The air samples were taken biweekly by the method of static chambers and gas
concentrations were determined by gas chromatography. In each sampling event, we
evaluated the soil moisture and mineral nitrogen content, deposition of litter and monitored
the soil and chamber air temperature. The forestation with both eucalyptus and acacia did not
alter significantly the soils fluxes of CH 4 and N 2 O in comparison to the native grassland
adjacent to each forest. The N 2 O flux are generally low, with most values ranging from –5 to
30 μg N m -2 h -1 , probably favoured by the low rainfall and soil mineral nitrogen levels during
the evaluated period. Similarly magnitude to the soil under native grassland, CH 4 oxidation
predominated in forested soils in the period of the experiment. The soil with two-year old
eucalyptus plantation tended to emit more N 2 O than the four-year plantation. The harvest of
acacia increased the soil N 2 O emission, likely due to the larger availability of mineral N in the
soil for the nitrification and denitrification processes. With respect to CH 4 , the largest
emission coincided with periods of higher soil temperature, which is coherent herewith
increased of the biological activity, especially in areas with less vegetation cover. The
contents of total organic carbon (TOC) and total nitrogen (TN) in soils with eucalyptus and
acacia were not significantly different from those observed in native grassland soil for most
layers. The low CH 4 and N 2 O emissions from forestry added to the carbon sequestration in the
plant biomass and wood products suggests that the change of land use for forestation is an
effective option for mitigating the GHG emissions and for increasing the carbon sequestration
in areas such as the Pampa Gaúcho.
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Toxidez do alum?nio e efici?ncia de diferentes tipos de poda em Bauhinia variegata L. / Toxicity of aluminum and efficiency of different types of pruning in Bauhinia variegata L.Machado, Alessandra de Lima 27 February 2015 (has links)
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Previous issue date: 2015-02-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The evaluation of toxicity caused by aluminum (Al) trees used in urban forestry is of great importance for the development of seedlings and plantings in appropriate conditions. The tree species Bauhinia variegata L. is commonly used in urban afforestation, requiring knowledge of their nutritional requirements and conflicts related to the presence of trees on the streets, for example, interference in the electricity distribution networks. Pruning is the main practice management done on trees planted in the streets. Optimizing the pruning process can generate benefits such as less frequent pruning, lower cost and higher efficiency, especially for the energy sector. The objectives of this study were to evaluate the influence of Al in the development of Bauhinia variegata seedlings, and analyze the effectiveness of different types of pruning cut with or without the use of Al, in order to reduce shoots. This study was developed in two stages, resulting in two chapters. The first, directly related to mineral nutrition, with the study aimed to investigate the effects of Al toxicity on growth and root development. Experiments were performed in simple and complete nutrient solution and in acid soil substrate. The second chapter presents the study to assess the effectiveness of different types of pruning cut made in adult plants of Bauhinia variegata, with and without the use of Al as a growth inhibitor. The results indicated that this species is sensitive to the toxicity of Al from the concentration of 50 ?M, being observed decrease in root growth rate and relative root elongation. The critical dose to paralyze Al root growth were 151,48 ?M of Al in simple nutrient solution and 388,72 ?M of Al in complete nutrient solution. Al caused increase in the diameter of the roots of seedlings from the concentration at 400 ?M solution. The application of limestone in acid soil favored the growth of plants of Bauhinia variegata, resulting in higher dry matter weight values of root and shoot dry mass weight. When pruning was held close to the trunk and Al application shoots were not observed until the last evaluation at 210 days after pruning. In pruning held close to the trunk without Al application occurred shoots. In the cuttings leaving stump 20 and 40 cm, with or without the application of Al occurred shoots / A avalia??o da toxidez causada pelo alum?nio (Al) em ?rvores utilizadas na arboriza??o urbana ? de grande import?ncia para o desenvolvimento de mudas e plantios em condi??es adequadas. A esp?cie arb?rea Bauhinia variegata L., ? comumente utilizada na arboriza??o de urbana, sendo necess?rio o conhecimento das suas exig?ncias nutricionais e dos conflitos relacionados ? presen?a das ?rvores nas ruas, como, por exemplo, a interfer?ncia nas redes de distribui??o de energia el?trica. A poda ? a principal pr?tica de manejo realizada nas ?rvores plantadas nas ruas. A otimiza??o do processo de podas pode gerar benef?cios como menor frequ?ncia de podas, menor custo e maior efici?ncia, especialmente para o setor el?trico. Os objetivos deste trabalho foram avaliar a influ?ncia do Al no desenvolvimento de mudas de Bauhinia variegata, e analisar a efici?ncia de diferentes tipos de corte em poda associado ou n?o ao uso de Al, de modo a diminuir brota??es. Estes estudos foram desenvolvidos em duas etapas, resultando assim em dois cap?tulos. O primeiro, relacionado diretamente ? nutri??o mineral, com o estudo direcionado ? investiga??o dos efeitos da toxidez do Al no crescimento e desenvolvimento de ra?zes. Foram realizados experimentos em solu??o nutritiva simples e completa e em substrato de solo ?cido. O segundo cap?tulo apresenta o estudo de avalia??o da efici?ncia de diferentes tipos de corte em podas realizadas em plantas adultas de Bauhinia variegata, com e sem a utiliza??o de Al como inibidor de crescimento. Os resultados indicaram que esta esp?cie ? sens?vel ? toxidez do Al a partir da concentra??o de 50 ?M, sendo observada diminui??o na taxa de crescimento radicular e na elonga??o radicular relativa. As doses cr?tica de Al que paralisaria o crescimento radicular foram de 151,48 ?M de Al em solu??o nutritiva simples e de 388,72 ?M de Al em solu??o nutritiva completa. O Al provocou aumento do di?metro das ra?zes de mudas a partir da concentra??o em solu??o de 400 ?M. A aplica??o de calc?rio em solo ?cido favoreceu o crescimento de plantas de Bauhinia variegata, resultando em maiores valores de peso de massa seca de raiz e peso de massa seca de parte a?rea. Quando a poda foi realizada rente ao tronco principal e com aplica??o de Al n?o foram observadas brota??es at? a ?ltima avalia??o, aos 210 dias ap?s a poda. Na poda realizada rente ao tronco principal sem aplica??o de Al ocorreram brota??es. Nas podas deixando toco de 20 e 40 cm, com ou sem aplica??o de Al, ocorreram brota??es.
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The Effect of Afforestation on Soil Microbes and Biogeochemistry across Multiple ScalesBerthrong, Sean Toshio January 2009 (has links)
<p>Afforestation, the conversion of historically treeless areas into forests, is a rapidly spreading land-use change with the potential to sequester carbon. Afforested plantations typically feature fast growing exotic tree species that give landowners rapid returns. The efficient growth of plantations compared to less intensively managed forests also can provide greater timber yields in a smaller area. This increased efficiency in turn could require fewer acres to meet global forest product demands and could also reduce the need to log intact primary forests. Reduced primary forest harvest and high primary productivity make afforestation a highly efficient carbon sequestration tool.</p><p> However, the rapid growth and planting disturbance due to afforestation can have deleterious effects on soils and hydrology that undermine its benefits in some locations. The effects on hydrology include depletion of groundwater and reduced or complete elimination of surface water flow. Additionally, groundwater use can lead to increased concentrations of salts and trace metals in soil that could be deleterious for future plant productivity. Plantations have also been shown to acidify surface soils and stream water and to reduce soil carbon and nitrogen.</p><p> Despite the known effects of afforestation on soils, there has been little research on the mechanisms controlling these effects. For instance, there have been few studies on the effects of afforestation on soil microbes which mediate most biogeochemical processes. There is also little knowledge on what controls the effects of afforestation on soil carbon and nitrogen, vital indexes of soil quality, across regions with high levels of afforestation. The overarching goal of this dissertation is to examine the effects of afforestation on soils, microbes, and biogeochemical processes across local, regional and global scales. Understanding the mechanisms by which afforestation alters soils and biogeochemical cycling and how these mechanisms change across different scales will aid in evaluating the true costs and benefits of afforestation. These results will be useful in determining if the benefits of afforestation will continue to outweigh its costs in the long-term.</p><p> The goal of Chapter 1 is to evaluate how afforestation across the globe affects mineral soil quality, including pH, sodium, exchangeable cations, organic carbon, and nitrogen, and to examine the magnitude of these changes in regions where afforestation rates are high. To control for different initial soil conditions across the globe, I examined paired sites of afforested plantations and controls. Controls included land-use types that are frequently afforested, such as grasslands, shrublands, and pastures. I also examined potential mechanisms to reduce the impacts of afforestation on soils and to maintain long-term productivity. Across diverse plantation types (153 sites) to a depth of 30cm of mineral soil, I observed significant decreases in nutrient cations (Ca, K, Mg), increases in sodium (Na), or both with afforestation. For the global dataset, afforestation reduced soil concentrations of the macronutrient Ca by 29% on average compared with native controls (p<0.05). Afforestation by Pinus alone decreased soil K by 23% (p<0.05). Overall, plantations of all genera also led to an average 71% increase of soil Na (p<0.05). Average pH decreased 0.3 units (p<0.05) with afforestation. Afforestation caused a 6.7% and 15% (p<0.05) decrease in soil C and N content respectively, though the effect was driven principally by Pinus plantations (15% and 20% decrease, p<0.05). Carbon to nitrogen ratios in soils under plantations were 5.7-11.6% higher (p<0.05). The major implication of these results are that in several regions with high rates of afforestation, cumulative losses of C, N, Ca, and Mg are likely in the range of tens of millions of metric tons. The decreases indicate that trees take up considerable amounts of nutrients from soils; harvesting this biomass repeatedly could impair long-term soil fertility and productivity in some locations. Based on this study and a review of other literature, I suggest that proper site preparation and sustainable harvest practices, such as avoiding the removal or burning of harvest residue, could minimize the impact of afforestation on soils. These sustainable practices could in turn slow erosion, organic matter loss, and soil compaction from harvesting equipment, maintaining soil fertility to the greatest extent possible. </p><p> Soil microbes are highly diverse and control most soil biogeochemical reactions. Given the observed changes in Chapter 1, in Chapters 2 and 3 I examined how microbial functional genes and biogeochemical pools responded to the altered chemical inputs accompanying afforestation. I examined paired native grasslands and adjacent Eucalyptus plantations (previously grasslands) in Uruguay, a region that lacked forests before European settlement. Along with measurements of soil carbon, nitrogen, and bacterial diversity, I analyzed functional genes using the GeoChip 2.0 microarray that simultaneously quantified several thousand genes involved in soil carbon and nitrogen cycling. Plantations and grasslands differed significantly in functional gene profiles, bacterial diversity, and biogeochemical pool sizes. Afforestation decreased both bacterial diversity and richness compared to grasslands, though diversity remained relatively high. Most grassland functional gene profiles were similar, but plantation profiles generally differed from grasslands due to differences in functional gene abundance across many microbial groups. Eucalypts decreased ammonification and N-fixation functional genes by 11% and 7.9% (p<0.01) which correlated with decreased microbial biomass N and more NH4+ in plantation soils. Chitinase, an important carbon polymer degrading enzyme, decreased in functional gene abundance 7.8% in plantations compared to grasslands (p=0.017), and C polymer degrading genes decreased by 1.5% overall (p<0.05), which likely contributed to 54% (p<0.05) more C in undecomposed extractable soil pools and 27% less microbial C (p<0.01) in plantation soils. In general, afforestation altered the abundance of many microbial functional genes corresponding with changes in soil biogeochemistry. These changes were driven by shifts in the whole community functional gene profile, not just one or two constituent microbial taxa. Such changes in microbial functional genes correspond with altered C and N storage and have implications for long-term productivity in these soils.</p><p> The area studied in Chapters 2 and 3 lies near the middle of a precipitation gradient that stretches across the Rio de la Plata grasslands. In Chapter 4 I studied if the effects of afforestation on soil C and N from Chapters 2 and 3 varied with different precipitation levels. The effect of afforestation on soil C has been shown to depend on mean annual precipitation (MAP), with drier sites gaining C and wetter sites losing C with afforestation. This precipitation dependence of soil C changes with afforestation may be controlled by changes in soil nitrogen (N) cycling. In particular, loss of N due to leaching after afforestation could lead to soil C losses. However, the link between C and N changes due to afforestation has primarily been suggested by models and to my knowledge has never been explicitly tested across a precipitation gradient. The goal of this study was to test how precipitation affects changes in labile and bulk pools of soil C and N across a precipitation gradient, which will provide novel insight into the linkage between land-use change, different pools of soil C and N, and precipitation. I conducted this study across a gradient of precipitation in the Rio de la Plata grasslands of Argentina and Uruguay which ranged from 600mm to 1500mm of precipitation per year. The sites were all former grasslands that had been planted with Eucalyptus. I found that changes in bulk soil C and N were related to MAP with drier sites gaining and wetter sites losing C and N (R2=0.59, p=0.003), which supports the idea that N losses are strongly linked to C losses with afforestation. C and N in microbial biomass and extractable pools followed similar patterns to bulk soil C and N. Interestingly, losses of C and N decreased as the plantations aged, suggesting that longer rotation times for plantations could reduce potential soil carbon and nitrogen losses. These results indicate that afforestation is still be a valuable tool for carbon sequestration, but calculations of the benefits of afforestation must take into account site factors such as age and precipitation to accurately calculate total sequestration benefit and ensure continued high productivity and carbon sequestration.</p><p> In conclusion, afforestation could be an effective tool for carbon sequestration. However, its benefits need to be carefully weighed against its costs for soil such as reduced microbial diversity, decreased soil microbial functional capacity, losses of soil organic matter, and nutrient depletion. Careful management and consideration of afforestation is needed to ensure the greatest benefits with the least long-term damage to soils.</p> / Dissertation
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Juodalksnynų augimo ypatumai Lc augavietėje Šakių miškų urėdijoje / The growth peculiarity of black alders in Lc habitat, in Šakiai forest enterpriceBacevičius, Marius 14 January 2009 (has links)
Magistro darbe tiriami Lc augavietės juodalksnynai, jų paplitimas, taksaciniai rodikliai bei juodalksnynų atsikūrimo galimybės šioje augavietėje.
Darbo objektas – Šakių miškų urėdijos Lc augavietės juodalksnynai.
Darbo tikslas - nustatyti juodalksnynų paplitimą, našumą ir atsikūrimo galimybes Lc augavietėje Šakių miškų urėdijoje.
Darbo metodai – Tyrimams atlikti buvo išrinkti visi brandos amžių pasiekę ir pribręstantys medynai, kuriuose juodalksnis yra vyraujanti medžių rūšis. Iš viso buvo išskirti 43 tokie sklypai. Visuose šiuose sklypuose buvo patikslinta augaviečių identifikacija remiantis įprastais dirvožemio mokslo metodais. Žolinei augalijai ir trakui įvertinti buvo išskirti apskaitos bareliai, kuriose buvo nustatyta jų rūšinė sudėtis ir projekcinis padengimas. Apibūdinant medyną buvo įvertinti visi pagrindiniai taksaciniai medyno rodikliai remiantis miško taksacijos metodais. Juodalksnynų atsikūrimo nustatymui, tyrimai buvo atlikti visose paskutinių penkių metų pagrindinių plynų kirtimų Lc augavietės biržėse.
Darbo uždaviniai – Nustatyti juodalksnynų paplitimą Lc augavietėje. Įvertinti Lc augavietės identifikavimą miškotvarkos medžiagoje pagal tyrimų natūroje rezultatus. Atlikti juodalksnynų dendrometrinį įvertinimą. Įvertinti miško žėlimą plynose juodalksnynų kirtavietėse.
Darbo rezultatai – Juodalksnynai Lietuvoje už¬ima 136,1 tūkst. ha, arba 6,7% visų medynų ploto. Lc augavietės juodalksnynai sudaro 5,6% bendro juodalksnynų ploto, o Šakių miškų urėdijoje 8,4%... [toliau žr. visą tekstą] / The final thesis makes researches about the Lc black alders habitat, their spread, valuation index and the possibility of regeneration in these habitats.
Object of study – black alders in Lc habitat, in Šakiai forest enterprice.
Goal of study - to identify the black alders productivity, spread and possibilities of regeneration in Lc habitat, in Šakiai.
Methods of study – all the ripe arboretums, where black alder was the main sort, were taken as research objects. There were 43 areas of this type, and in all of these the habitat identification was specified together with dendrometrical assessment. Accounting barels were used to evaluate verdure and undergrowth. So was their sort composition and projection stratification established. The forest valuation was described with arboretum ant methods of afforestation inspections.
For the regeneration of black alders possibilities, analysis were made in all bare cutting areas of Lc habitats for the last 5 years.
Task of study – Specify the black alders spread in Lc habitat. Evaluate identification of Lc habitat made by forest enterprise, refering the newly made analysis in the place. Do the dendrometrical assessment. Evaluate forest growing in bare cutting areas of black alders.
Results of study– The habitats of black alders takes 136100 ha, or 6,7% of all afforestation in Lithuania. 5,6% of all black alders grow in Lc habitat, and 8,4% in Šakiai forest enterprice. After precising black alder habitat in Lc, the results were: 37% -... [to full text]
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Biodiversity criteria and indicators for the sustainable management of industrial plantations.Linnett, Elizabeth. January 1999 (has links)
Abstract not available. / Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 1999.
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Long-run Implications of a Forest-based Carbon Sequestration Policy on the United States Economy: A Computable General Equilibrium (CGE) Modeling ApproachMonge, Juan 2012 August 1900 (has links)
The economic impacts of a government-funded, forest-based sequestration program were analyzed under two different payment schemes. The impacts were obtained by developing a regional, static CGE model built to accommodate a modified IMPLAN SAM for a determined region in the United States for 2008. The IMPLAN SAM was modified to accommodate the more conventional factors of production (labor, capital and land) and to account for land heterogeneity using the Major Land Resource Areas (MLRA). The regional aggregation considered included the Southern, Northeastern, Southwestern and Midwestern regions. The two policy scenarios considered consisted of two CO2-offset payment schemes: 1) the government compensates the generation of CO2-offsets only by the land converted to a carbon graveyard and 2) the government additionally compensates the CO2 offsets generated as a by-product by the existing commercial logging activity. By doing an analysis of the model with different budget magnitudes under the two scenarios, two different CO2-offset supply schedules were obtained with their respective CO2-offset price and quantity sets.
For a budget allocation of $6.9 billion, approximately 1 billion metric tons of CO2 offsets (15% of U.S. 2008 total GHG emissions) were produced in the first scenario versus 0.8 billion metric tons (11% of U.S. 2008 GHG net emissions) in the second one. Fifty million acres were diverted out of agriculture and commercial forestry land to the carbon graveyard mainly in the Northern, Western and Central Great Plains in the first scenario. Twenty two million acres were diverted out of agricultural land to the carbon graveyard and commercial logging mainly in the Northern and Western Great Plains; and the Eastern and Western boundaries of the Appalachian Mountains in the second scenario.
Both scenarios resulted in higher land and agricultural commodity prices, lower consumption of agricultural commodities by households, lower agricultural exports and higher imports. The payment structure of the second scenario benefited the commercial logging industry, increasing its production and exports, and decreasing its imports. The non-agricultural sectors mostly impacted by the two policy scenarios were the manufacturing, construction and government employment sectors.
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Root associated fungi of conifer seedlings and their role in afforestation of agricultural land /Menkis, Audrius, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.
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Evaluating the success of oak afforestation on former agricultural lands in southern IllinoisNickelson, Joshua Bradley 01 December 2014 (has links)
AN ABSTRACT OF THE THESIS OF Joshua B. Nickelson, for the Masters of Science degree in Forestry, at Southern Illinois University Carbondale TITLE: EVALUATING THE SUCCESS OF OAK AFFORESTATION ON FORMER AGRICULTURAL FIELDS IN SOUTHERN ILLINOIS Major Professor: Dr. Eric Holzmueller The establishment of oak (Quercus spp.) plantations has increased over the past two to three decades to reduce fragmentation and promote wildlife habitat throughout the Midwestern United States. However, influences such as competing vegetation, previous land cover, plantation size, and site preparation techniques may have varying outcomes on restorative successes. We established 219 plots (.02 ha) in 29 oak plantations located within Crab Orchard National Wildlife Refuge (Williamson County, Illinois) 15-18 years after mechanical planting. Sampling data for all trees over breast height included species, diameter, and lianas existence on the main bole of the tree. Additionally, free-to-grow status was recorded for all oak saplings and estimated cover of the exotic invasive shrub Elaeagnus umbellata and vine Lonicera japonica were documented. Results show significantly higher numbers of total oaks and free-to-grow oaks in plantings previously cropped in clover and soybeans when compared to the fallow sites host to brush species that received treatment (mowing and or herbicidal application). Significantly less oaks in the soybean and clover categories possessed a vine on the main bole of the tree when compared to the treated brush sites. Brush sites showed a significantly less number of total trees compared to clover and soybean covers and a higher percent of autumn olive cover (%) compared to soybeans. No significance was found in the percent of oaks with a vine, the percent of oaks overtopped, E. umbellata density or L. japonica cover (%) across the four previous vegetation categories. One treatment of pre-planting mowing and herbicidal application is not effective on fallow sites that are host to early successional species and money should not be invested on Quercus trees or mowing and herbicidal treatments in these scenarios. The results suggest that it is best to plant Quercus species immediately following clover or soybean harvest on abandoned agricultural lands before early successional species become established.
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Respostas de comunidades de aves ao florestamento dos campos sulinos : integrando diversidade taxonômica, filogenética e funcionalJacoboski, 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.
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Caracterização e análise do patrimônio arbóreo da malha viária urbana central do município de São Carlos-SP / Characterization and analysis of heritage tree loop road of center urban city of São Carlos-SPSucomine, Nivia Maria 22 October 2009 (has links)
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Previous issue date: 2009-10-22 / Financiadora de Estudos e Projetos / The road afforestation from the central urban area of São Carlos-SP was studied in order to know it and diagnose it in order to provide support for its maintenance and expansion. To this end, we performed a qualitative and quantitative assessment of tree cover, all its information and analysis developed and entered into a computerized database. We have found 103 different plant species in a total of 2626 individuals, 147 killed, 502 seedlings and 1977 adults. Schinus molle and Murraya paniculata were the most abundant species. For the diversity index and the average index of trees per kilometer of street obtained the values 3.18 and 26.73 respectively. The average diameter at breast height (DBH) was 21.4 cm; 55% of plants had height less than 5.40 m; 45% of the population is compound of native species and only 26 species are fructiferous. Small was the number of affected plants or plant injury, but more significant was the damage caused by the crown pruning irregular. 899 individuals were in conflict with one or more equipment around and 76% had little or no free space pavement. The results obtained it was concluded that this area has a high diversity floristic. In quantitative terms, this population was still very poor, but the overall situation of trees was satisfactory. It is recommended that an intensive program of planting of trees (with less abundant species) in the streets with the lowest level of individuals and another program for the maintenance and conservation of the stock already in place, pruning and expansion of free spaces on the sidewalks. / A arborização viária da área central urbana do município de São Carlos-SP foi estudada com o objetivo de conhecê-la e diagnosticá-la a fim de oferecer subsídios para a sua manutenção e incremento. Para tal, foi realizado um levantamento quali-quantitativo da cobertura arbórea, sendo todas suas informações e análises inseridas e desenvolvidas em um banco de dados informatizado. Foram encontradas 103 espécies botânicas distintas num total de 2626 indivíduos, sendo 147 mortos, 502 mudas e 1977 adultos. Schinus molle e Murraya paniculata foram às espécies mais abundantes. Para os índices de diversidade e de indivíduos por quilometragem de rua, obteve-se os valores 3,18 e 26,73 respectivamente. O diâmetro a altura do peito (DAP) médio foi de 21,4cm; 55% dos vegetais apresentaram altura menor que 5,40m; 45% da população são nativas e apenas 26 espécies são frutíferas. Pequeno foi o número de plantas acometidas de injúria ou fitossanidade, porém o mais significativo foram os danos nas copas decorrentes de podas irregulares. Dentre todos os indivíduos, 899 estão em conflito com um ou mais equipamento em entorno, sendo a fiação aérea a principal, e 76% possuíam pouco ou nenhum espaço livre de pavimentação. Por meio dos resultados obtidos, concluiu-se que a composição florística dessa área é bem diversa. Em termos quantitativos, essa população é ainda muito deficiente, mas a situação geral das árvores é bem satisfatória. Recomenda-se um programa intensivo de incentivo de plantio de mudas (com espécies menos abundantes) nas ruas com menor índice de indivíduos e outro programa com vista à manutenção e conservação da arborização já implantada, podas e ampliação dos espaços livre de pavimentação nas calçadas.
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