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Comparison of Techniques for Estimation of Forest Soil CarbonAmichev, Beyhan Y. 01 May 2003 (has links)
Soil organic carbon represents the largest constituent of the global C pool and carbon budgets are studied by researchers and modelers in C cycling, global climate change, and soil quality studies. Pedon and soil interpretation record databases are used with soil and ecological maps to estimate regional SOC even though these databases are rarely complete for surface litter and mineral subsurface horizons.
The first main objective of the project is to improve the ability to produce soil organic carbon estimates from existing spatial soils datasets, such as STATSGO. All records in the STATSGO Layer table that were incomplete or appeared to be incorrectly filled with a null or zero value were considered invalid. Data sorting procedures and texture lookup tables were used to identify exiting correct (valid) data entries that were used to substitute invalid records. STATSGO soil property data were grouped by soil order, MLRA, layer number, and texture to produce replacement values for all invalid data used to calculate mass SOC. Grouping criteria was specific to each variable and was based on texture designations. The resulting filled and unfilled tables were used with procedures assuming Normal and Lognormal distribution of parameters in order to analyze variation of mass SOC estimates caused by using different computation techniques.
We estimated mass SOC to 2 m in Maine and Minnesota using filled and unfilled STATSGO data tables. Up to 54% of the records in Maine and up to 80% of the records in Minnesota contained null or zero values (mostly in fields related to rock fragments) that were replaced. After filling, the database resulted in 1.5 times higher area-weighted SOC. SOC calculated using the Normal distribution assumption were 1.2 to 1.5 times higher than those using the Lognormal transformation. SOC maps using the filled tables had more logical geographic SOC distribution than those using unfilled tables.
The USDA Forest Service collects and maintains detailed inventory data for the condition and trends of all forested lands in the United States. A wide range of researchers and landowners use the resulting Forest Inventory and Analysis (FIA) database for analytical and decision making tasks. FIA data is available to the public in transformed or aggregate format in order to ensure confidentiality of data suppliers.
The second main objective of this project was to compute SOC (kg m-2) results by FIA forest type and forest type group for three depth categories (25 cm, 1 m, and 2 m) at a regional scale for the 48 contiguous United States. There were four sets of results derived from the filled STATSGO and FIA datasets for each depth class by region: (1) SOC computed by the Lognormal distribution approach for (1a) all soil orders, (1b) without Histosols; and (2) SOC computed by the Normal distribution approach for (2a) all soil orders, (2b) without Histosols.
Two spatial forest cover datasets were relevant to this project, FIA and AVHRR. We investigated the effects of FIA inventory data masking for Maine and Minnesota, such as plot coordinates rounding to the nearest 100 arc-second, and the use of 1 km resolution satellite-derived forest cover classes from AVHRR data, on SOC estimates to 2 m by forest type group. SOC estimates by soil mapping unit were derived from fixed STATSGO database tables and were computed by the Lognormal distribution approach including all soil orders.
The methods in this study can be used for a variety of ecological and resource inventory assessments and the automated procedures can be easily updated and improved for future uses. The procedures in this study point out areas that could benefit the most during future revisions of STATSGO. The resulting SOC maps are dynamic and can be rapidly redrawn using GIS whenever STATSGO spatial or tabular data undergo updating. Use of pedon data to define representative values for all properties in all STATSGO layers and correlation of STATSGO layers to soil horizons will lead to vast improvement of the STATSGO Layer table and promote its use for mass SOC estimation over large regions. / Master of Science
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Quantifying the Mechanisms Behind Carbon Sequestration and Soil Health Following Compost Application in a Rangeland ChronosequenceDamaschino, Grace 01 December 2024 (has links) (PDF)
Compost application to rangelands has the potential to sequester carbon (C) and add essential plant nutrients to the soil. The California Department of Food and Agriculture's (CDFA) Healthy Soils Project (HSP) provides financial support to farmers and landowners to implement innovative practices that promote soil health. The CDFA is currently recommending compost application rates of 6-10 tons per acre; however, previous research suggests that degraded soils may require a larger dose of compost to overcome limitations, therefore this recommendation might not meet soil health or soil carbon sequestration objectives. This study examines the compost rate effects on soil health, while also utilizing a comparison between soils with differing ages but similar environmental factors through the use of a rangeland chronosequence. Previous studies lack the combination of rate comparisons paired with soil development.
Compost was applied at rates of 0, 10, 20, and 30 tons/acre across the two marine terraces, T1 and T2. Terrace one (T1) is the less developed sandy loam, approximately 50,000 years old, and terrace two (T2) is the more developed sandy clay loam soil, approximately 120,000 years old. The interactions between the treatment and pre-existing mineral soil properties were examined to quantify the mechanisms behind C accrual and soil health on degraded soils. A randomized block design was utilized with 4 blocks per terrace, each 1-acre block containing each of the four treatments (Control, Low, Moderate, High).
Carbon sequestration was measured by testing soil GHG emissions as well as various pools of C within the soil such as total soil carbon (TC), labile soil carbon (POXC), and mineralizable carbon (Min C). Soil health factors were analyzed through measuring soil cations (Mg2+, Ca2+, Na+, K+), micronutrient/heavy metal availability (Znex, Mnex, Feex, Cuex), phosphorous (Olsen P), soil pH, total nitrogen (N) mineralization of nitrogen (PMN). Soil physical properties such as aggregate stability, water holding capacity (WHC), bulk density (Db), and aboveground biomass were also measured. Pre-existing site characteristics such as amorphous iron and aluminum oxides (Fe/Al-oxides) were examined as possible mechanisms for C storage. Data was analyzed via ANOVA and Tukey HSD mean separation to test significance. Linear mixed and mixed effects models were created to evaluate significance of site characteristics and assess which characteristic drives variability in soil C across the terraces.
Year one results show a statistically significant increase in percent carbon (TC) and labile carbon (POXC) in the top 5 cm of T2 between the 30 ton/acre treatment compared to 10 ton/acre treatment and the control. Similarly, levels of extractable Ca2+, K+, and Mg2+ were significantly higher in the plots with 30 t/acre of compost compared to the control plots in T2, as well as for Kex, in T1. Finally, WHC significantly improved in the soil treated with 30 t/acre of compost compared to 10 t/acre in T2, and Db significantly improved in the soil treated with 30 t/acre of compost compared to the control in T2. One-year post-application, soil C, soil mineralogy/health, and soil physical properties significantly increased and/or improved when treated with the high 30 t/acre compost levels compared to the low and/or control treatments.
Two years after compost application, we see similar results with increased TC, Caex, and Mgex in the high application rates compared to the low and control in T2, and we also see the emergence of increased total nitrogen (TN) and extractable Znex in the 30 t/acre treatment plots compared to the 10 t/acre and control plots in T2. However, two years post-application, POXC, WHC, and Db now longer showed significant differences between any rates in T2, though they each appeared to follow the same trend.
Interestingly, results three years post-application showed continued TC and TN, Ca2+ and Mg2+ and Znex significance in the 30 t/acre treated plots compared to the low 10 t/acre plots in T2. Furthermore, TC, Min C, and TN all significantly increased in the 30 t/acre treatment plots in 2023 compared to the level’s measures in the 30 t/acre plots in 2021, suggesting continued C-sequestration and soil health benefits up to three years after a single compost application. Other soil health components such as POXC, extractable cations (K+, Ca2+, Na+, and Mg2+), Znex and Cuex, did not continue to increase into year three, but rather remained constant or slightly decreased, indicating an initial spike in nutrients immediately after compost application, followed by a decline back to “normal” values for some aspects of soil health. However, Alox did emerge as significantly higher under the 30 t/acre treatment compared to the 10 t/acre treatment in T2 in year three and showed a trend towards increasing levels of Alox between 2021 and 2023. This could indicate a lag in the effects of compost on the soil, with some nutrients emerging as significant three years after compost application.
An analysis of correlation between C content (TC, Min C, and POXC) and mineralogical properties (Fe/Al-oxides, clay percent) and the compost treatment levels were determined using linear mixed-effects models (MEM). Across all three years, the linear MEM showed that Feox, Alox, and clay percent were the main predictors of TC storage, with Alox showing the strongest effect, while compost treatment was significant, but had a smaller effect size. For Min C, the MEM shows Alox is the most significant predictor across all years, but an R2 of only 0.18 suggests that factors not included in the model, or year-specific conditions, are also affecting MinC. The MEM for POXC shows that Feox, Alox and clay impact POXC in 2021, with Feox influencing POXC across three years.
No significant treatment effects were observed on amorphous iron (Feox) or clay content on either terrace in any year, meanwhile Alox levels significantly increased with increasing compost application in 2022 and 2023. between terraces in 2022 and 2023, with T2 showing higher levels compared to T1. The linear MEM results indicate that Feox, clay percent, and Alox all significantly predict C storage within the soil after accounting for compost treatments. Since compost directly affects Alox, it is likely that compost and Alox are collinear, and thus compost indirectly influences TC through increasing Alox. In 2021, Feox and clay percent solely predict C storage, by 2023 Alox emerges as the most significant predictor of C storage. This collinearity may be attributed to the release of Alox into the soil from compost treatments. Alox is both a mediator through which compost influences C, and still a valid, strong predictor of TC storage.
The findings from this analysis indicate 1) an application rate of 30 tons/acre is more effective at sequestering C and improving soil health over the traditional 10 tons/acre, 2) pre-existing site characteristics and differences in pedogenic soil development (Alox and Feox and clay percent) are the key factors modulating soil health outcomes from compost application, and 3) continued C benefits across multiple years may be realized after a one-time application.
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Carbono no solo em sistemas integrados de produção agropecuária no Cerrado e na transição Cerrado - Amazônia / Soil carbon under integrated agricultural production systems in the Brazilian savannah (Cerrado) and in the Cerrado-Amazon transition zoneOliveira, Janaína de Moura 26 June 2015 (has links)
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Previous issue date: 2015-06-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Integrated crop-livestock (iCL) and integrated crop-livestock-forest (iCLF)
systems are pointed out as potential soil carbon sinks. However, there are few scientific
studies that evaluated the real contribution of these production systems. This work
included two studies. The first was to evaluate soil carbon accumulation and its origin in
iCLF in the transition zone of the Cerrado-Amazon biomes; the second aimed to calibrate
and validate the CQESTR model for the Cerrado ecosystem and to evaluate the effect of
soil management practices, including iCL and various scenarios on soil organic carbon
(SOC) over time. For the first study two areas under iCLF (iCLF1 and iCLF3, with one
and three rows of Eucalyptus urograndis by hedgerow, respectively) were selected. They
were cultivated in this system since 2009 in Nova Canaã do Norte, MT. A continuous
pasture was used as reference. Soil samples were taken from eight layers (0.0 to 1.0 m) for
the evaluation of the bulk density, texture, total C and N and δ¹³C. The second study was
conducted in the Cerrado biome. The evaluated areas (Paddock 4 - P4 and Paddock 5 - P5
has been being managed in iCL since 2000. Bulk density and the organic matter content
were determined for the 0.0-0.1 and 0.1-0.3 m layers. The CQESTR is a process based
model which simulates the effect of climate, crop rotation and tillage management
practices on SOC. The model was calibrated with P5 data and validated with P4 data. Its
performance was evaluated using statistical regression analysis and the root mean square
deviation (MSD). For the first study, the soil C stocks and isotopic composition were
affected by the implementation of the iCLF system. The forest component was an
important factor for soil C accumulation for both areas under iCLF. The N can be a
limiting factor for C accumulation. We concluded that iCLF affected soil C and N stocks in
the short term, however, longer iCLF deployment time would be necessary to elucidate the
impact of iCLF in the long-term. In the second study model calibration was performed by
adjusting the basic decomposition rate coefficient. The measured and simulated values
were significantly correlated with an MSD of 2.11, indicating that the model captured
spatial-temporal dynamics of SOC in the topsoil. However, CQESTR underestimated SOC
for the 0,1-0,3 m layer, probably due to lack of site specific grass or crop root biomass and
distribution data under tropical conditions. Additional calibration is required to improve
prediction of SOC stabilization process in the subsoil layers of tropical soils. In the long
term (20 years), for the superficial (0,0-0,1 m) soil layer, the model simulated C
accumulation in iCL and C loss in soybean/corn grain production system independently of
the use of zero-tillage or conventional tillage in either of these systems under Cerrado
conditions. / Os sistemas de integração lavoura-pecuária (iLP) e integração lavourapecuária-
floresta (iLPF) são apontados como potenciais acumuladores de carbono no solo.
Entretanto, ainda há poucos estudos científicos que avaliaram a real contribuição desses
sistemas de produção. O presente trabalho incluiu dois estudos para avaliação desses
sistemas. O primeiro teve por objetivo avaliar a acumulação e a origem do carbono do solo
em iLPF na região de transição dos biomas Cerrado-Amazônia; e o segundo estudo teve
por objetivo calibrar e validar o modelo CQESTR para o ecossistema Cerrado bem como
avaliar o efeito de práticas de manejo do solo, incluindo iLP e vários cenários no carbono
orgânico do solo (COS) ao longo do tempo. Para o primeiro estudo foram selecionadas
duas áreas sob iLPF (iLPF1 e iLPF3, sistemas com uma linha e três linhas de Eucalyptus
urograndis por renque, respectivamente) cultivadas nesse sistema desde 2009 e uma
pastagem no município de Nova Canaã do Norte, MT. Amostras de oito camadas (0,0-1,0
m) foram tomadas para avaliação da densidade, textura, teor de C e N total e δ¹³C. O
segundo estudo foi conduzido no bioma Cerrado, em área que vem sendo manejada em iLP
desde 2000. Foram avaliadas duas áreas, os Piquete 4 (P4) e Piquete 5 (P5). A densidade
do solo e o teor de matéria orgânica foram determinados para as camadas 0,0-0,1 e 0,1-0,3
m. O CQESTR é um modelo de simulação de C baseado em processos que simula o efeito
do clima, rotações de cultura e práticas de manejo no COS. O modelo foi calibrado com
dados do P5 e validado com P4. Seu desempenho foi avaliado usando análise estatística de
regressão e o desvio médio quadrático (MSD). No primeiro estudo, a composição isotópica
do solo e os estoques de C foram afetados pela implantação do sistema iLPF. O
componente florestal foi importante fator na acumulação de C em ambas as áreas sob
iLPF. O N pode ser um fator limitante para a acumulação de C. Conclui-se que o iLPF
afeta os estoques de C e N do solo no curto prazo, entretanto, novas avaliações com maior
tempo de implantação do iLPF poderiam auxiliar na elucidação do comportamento desses
elementos no sistema em longo prazo. No segundo estudo, a calibração do modelo foi
realizada pelo ajuste do coeficiente da taxa de decomposição básica. Os valores simulados
e medidos foram significativamente correlacionados com um MSD de 2,11, indicando que
o modelo capturou satisfatoriamente a dinâmica temporal do COS na camada superficial.
Entretanto, o CQESTR subestimou o COS para a camada subsequente 0,1-0,3 m,
provavelmente devido às diferenças na biomassa e distribuição de raízes de gramíneas de
clima tropical e temperado. Calibração adicional é requerida para melhorar a predição do
COS e processos de estabilização nas camadas subsuperficiais de solos tropicais. Para a
camada 0,0-0,1 m, em longo prazo (20 anos), o modelo simulou acumulação de C em iLP e
decréscimo de C em sistema de produção com sucessão soja/milho, tanto sob plantio direto
quanto preparo convencional em condições do Cerrado.
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Upřesnění sekvestrace uhlíku v půdě v severní části Českého krasu / Soil carbon sequestration in northern part of Czech karstPolická, Petra January 2014 (has links)
Due to climate change there is a growing concern for soil organic carbon reservoires. The soil is the largest terrestrial pool of organic carbon and its balance is being increasingly disturbed by conversion of natural to managed ecosystem (for agriculture, forestry and urbanization). There are still large uncertainities with estimating real amount of organic carbon sequestrated in soils. Therefore a number of regional and national soil inventories and monitoring networks are currently established or tested to verify soil carbon changes. Thesis is focused on estimation of soil organic carbon pools in the area of Czech basic map Beroun 12-41-08. It evaluates available soil data and restrictions of their use. Especially is focused on comprehensive soil survey undertaken between 1961 and 1970, on soil properties change in time and how to get missing bulk densities of the soil, particularly through pedotransfer functions. Powered by TCPDF (www.tcpdf.org)
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Estoques de carbono do solo em áreas de reflorestamento: bases para projetos de Mecanismo de Desenvolvimento Limpo / Soil carbon stocks in reforestation areas: bases for Clean Development ProjectsMoreira, Cindy Silva 09 November 2010 (has links)
Considerando a grande importância do seqüestro de carbono (C) nos solos florestais, observa-se pequena quantidade de projetos de MDL que incluem esse compartimento como agente da mitigação do aquecimento global. Isso ocorre pelo fato da quantificação dos estoques de C do solo representar maiores desafios se comparada aos demais componentes dos ecossistemas florestais. Sabendo-se das dificuldades econômicas e ambientais envolvidas na adoção desse tipo projeto e da importância das florestas na mitigação da mudança do clima, o objetivo desse trabalho foi avaliar o desempenho de metodologias para a obtenção do estoque de C do solo em duas áreas de reflorestamento e suas respectivas linhas de base (usos do solo anteriores aos plantios, i.e. pastagens e vegetações nativa), como base para diminuir a relação custo-benefício de projetos de MDL. Para alcançar o objetivo principal, a presente pesquisa foi composta das seguintes etapas: (i) estudo da variabilidade espacial do C do solo em uma área de reflorestamento com espécies nativas, estabelecida em Cotriguaçú/MT (Área I) e em uma cronossequência de plantio de eucalipto, localizada em Avaré/SP (Área II); (ii) determinação do tamanho da parcela e do nº ideal de amostras a partir da dependência espacial do C nos reflorestamentos; (iii) estimativa dos teores de C e densidades do solo (Ds) pela Espectroscopia de Reflectância no Infravermelho Próximo (NIRS) e Médio (MIRS), visando a redução dos custos analíticos sem prejuízo da qualidade dos resultados; e (iv) cálculo dos estoques de C do solo nas áreas e estimativa do balanço de carbono do projeto de MDL conduzido na Área II, utilizando a ferramenta EX-ACT (Ex-Ante Carbon Balance Tool). Os resultados obtidos confirmaram a existência de importante variabilidade espacial do C do solo nas áreas e dependência espacial forte em todos os sistemas de manejo estudados. A análise do número ideal de amostras de solo indicou que a coleta de cinco pontos por parcela é tão precisa quanto uma amostragem com mais pontos. O tamanho ideal das parcelas variou de 361-841 m2 nos plantios da Área I e de 900-3721 m2 nos plantios da Área II. O desempenho dos métodos NIRS e MIRS na estimativa do teor de C dos solos foi bastante satisfatório, principalmente quando os modelos testados foram calibrados com quantidades entre 5-10% do conjunto de dados total. Os resultados da estimativa da Ds foram um pouco inferiores aos do C. Os estoques de C do solo obtidos na Área I foram superiores aos da Área II. Considerando apenas o solo, é possível afirmar que o potencial de geração de créditos de C é maior no reflorestamento com espécies nativas sob solo argiloso do que no reflorestamento com eucalipto em solo arenoso. O balanço de C do projeto conduzido na Área I indicou o seqüestro de quase três milhões de toneladas de CO2eq em 40 anos. Espera-se que este estudo contribua para o aumento da inclusão do solo em projetos de MDL, uma vez comprovada a possibilidade de redução dos custos associados à obtenção e determinação dos estoques de C nesse compartimento / Considering the great importance of carbon sequestration (C) in forest soils, there are few CDM projects that include this compartment as an agent of global warming mitigation. This occurs because the quantification of soil C stocks represents a bigger challenge when compared to other components of forest ecosystems. Considering the economic difficulties and environmental issues involved in adopting this type of project and the importance of forests in mitigating climate change, the objective of this study was to evaluate the performance of methods for obtaining soil C stocks in two forestry areas and their respective baselines (land use prior to planting, i.e. pastures and native vegetation) as a basis for reducing the cost-benefit ratio of CDM projects. To achieve the main objective, this research was composed of the following steps: (i) estimating the spatial variability of soil C in an area reforested with native species, established in Cotriguaçú, MT (Area I) and a Eucalyptus chronosequence, located in Avaré, SP (Area II), (ii) determining the optimal amount of soil samples and the plot size from the soil C spatial dependence range in the reforestation areas, (iii) estimating soil C content and bulk density (BD) by Near and Mid Infrared Reflectance Spectroscopy (NIRS and MIRS, respectively) to reduce analytical costs without affecting the quality of the results, and (iv) calculating soil C stocks in both areas and estimating the carbon balance of a CDM Project conducted in Area II, using EX-ACT (\"Ex-Ante Carbon Balance Tool\"). The results confirmed the existence of significant soil C spatial variability in both areas and a strong spatial dependence at all plots. The analysis of the optimal number of soil samples indicated that the sampling procedure with five points per plot is as accurate as intensive sampling. The optimum size of plots ranged from 361-841 m2 at Area I plantations and from 900-3721 m2 at Area II. The performance of MIRS and NIRS to estimate the soil carbon content was very satisfactory, especially when the models were calibrated with amounts between 5-10% of the total data set. The estimations of BD were slightly less precise than those of soil C content. The soil C stocks obtained at Area I were higher than Area II. Considering only the soil compartment, it is clear that the potential for C credit generation in a reforestation with native species on a clayey soil is higher than in a reforestation with eucalyptus on a sandy soil. The C balance of the CDM project conducted in Area I is expected to sequester almost three million tones of CO2 eq in 40 years. We hope this study contributes to the increased inclusion of soil in CDM projects, by confirming the feasibility of reducing the costs associated with both sampling and analytical procedures
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Mapping soil organic carbon storage in deep soil horizons of Amazonian Podzols / Mapeamento do estoque de carbono orgânico em horizontes profundos de Espodossolos da AmazôniaPereira, Osvaldo José Ribeiro 19 January 2016 (has links)
The Podzols of the world are divided into intra-zonal and zonal according to then location. Zonal Podzols are typical for boreal and taiga zone associated to climate conditions. Intra-zonal podzols are not necessarily limited by climate and are typical for mineral poor substrates. The Intra-zonal Podzols of the Brazilian Amazon cover important surfaces of the upper Amazon basin. Their formation is attributed to perched groundwater associated to organic matter and metals accumulations in reducing/acidic environments. Podzols have a great capacity of storing important amounts of soil organic carbon in deep thick spodic horizons (Bh), in soil depths ranging from 1.5 to 5m. Previous research concerning the soil carbon stock in Amazon soils have not taken into account the deep carbon stock (below 1 m soil depth) of Podzols. Given this, the main goal of this research was to quantify and to map the soil organic carbon stock in the region of Rio Negro basin, considering the carbon stored in the first soil meter as well as the carbon stored in deep soil horizons up to 3m. The amount of soil organic carbon stored in soils of Rio Negro basin was evaluated in different map scales, from local surveys, to the scale of the basin. High spatial and spectral resolution remote sensing images were necessary in order to map the soil types of the studied areas and to estimate the soil carbon stock in local and regional scale. Therefore, a multi-sensor analysis was applied with the aim of generating a series of biophysical attributes that can be indirectly related to lateral variation of soil types. The soil organic carbon stock was also estimated for the area of the Brazilian portion of the Rio Negro basin, based on geostatistical analysis (multiple regression kriging), remote sensing images and legacy data. We observed that Podzols store an average carbon stock of 18 kg C m-2 on the first soil meter. Similar amount was observed in adjacent soils (mainly Ferralsols and Acrisols) with an average carbon stock of 15 kg C m-2. However if we take into account a 3 m soil depth, the amount of carbon stored in Podzols is significantly higher with values ranging from 55 kg C m-2 to 82 kg C m-2, which is higher than the one stored in adjacent soils (18 kg C m-2 to 25 kg C m-2). Given this, the amount of carbon stored in deep soil horizons of Podzols should be considered as an important carbon reservoir, face a scenario of global climate change / Os Espodossolos podem ser divididos em zonais e intrazonais de acordo com área onde ocorrem. Os Espodossolos zonais são típicos de áreas boreais e taiga, delimitados por condições climáticas. Já os intrazonais não são condicionados pelo clima. Os Espodossolo intrazonais brasileiros ocupam uma grande extensão da alta bacia amazônica, tendo sua formação atribuída à ocorrência de lençóis freáticos suspensos associados à acumulação de complexos organometálicos em ambientes ácidos redutores. Esses solos tem a capacidade de estocar grandes quantidades de carbono orgânico em horizontes espódicos profundos (Bh), em profundidades que podem variar de 1,5m a 5m. Pesquisas atuais relacionadas ao estoque de carbono em solos amazônicos, não levam em consideração os estoques encontrados no horizonte Bh (abaixo de 1m de profundidade). Sendo assim, o principal objetivo da presente pesquisa foi quantificar e mapear o estoque de carbono nos solos da bacia do Rio Negro, tendo-se em vista aquele estocado no primeiro metro de solo, bem como o carbono armazenado em até 3m de profundidade. A quantidade de carbono orgânico estocado nos solos da bacia do Rio Negro foi estimada em diferentes escalas de mapeamento, desde mapas locais até a escala da bacia do Rio Negro. Imagens de sensoriamento remoto de alta resolução espacial e espectral foram essenciais para viabilizar o mapeamento dos solos nas áreas estudadas e permitir a estimativa do estoque de carbono. Uma análise multisensor foi adotada buscando-se gerar informações biofísicas indiretamente associadas à variação lateral dos tipos de solo. Após o mapeamento do estoque de carbono em escala regional, partiu-se para a estimativa na escala da bacia do Rio Negro, com base em análise geoestatística (krigagem por regressão linear), imagens de sensoriamento remoto e base de dados de domínio público. Após o mapeamento do estoque de carbono na escala da bacia, constatou-se que os Espodossolos têm um estoque médio de 18 kg C m-2, para 1m de profundidade, valor similar ao observado em solos adjacentes (Latossolos e Argissolos) os quais tem um estoque de 15 kg C m-2. Quando são considerados os estoques profundos, até 3m, a quantidade de carbono dos Espodossolos é superior com valores variando de 55 kg C m-2 a 82 kg C m-2. Estoque relativamente maior que aquele observado em solos adjacentes para esta profundidade (18 kg C m-2 a 25 kg C m-2). Portanto, o estoque de carbono profundo dos Espodossolos, não deve ser negligenciado levando-se em conta cenários futuros de mudanças climáticas
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Emissão de CO2 do solo associada à escarificação em latossolo e em argissolo / Soil CO2 emission associated with the chiseling in latossolo and in argissoloSouza, Luma Castro de [UNESP] 16 March 2017 (has links)
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Previous issue date: 2017-03-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A operação de escarificação altera a estrutura do solo, afetando a dinâmica da emissão de CO2 do solo em curto período de tempo. Assim, com este estudo, objetivou-se: i - investigar a variação temporal da emissão de CO2 do solo após escarificação para o plantio da cana-de-açúcar em Latossolo e em Argissolo; ii - caracterizar a emissão de CO2, associada à distribuição de poros, em Latossolo e em Argissolo, submetidos à escarificação na linha de plantio e escarificação em área total para o plantio da cana-de-açúcar. O delineamento experimental utilizado foi em parcelas grandes pareadas. Os tratamentos utilizados consistiram na escarificação na linha de plantio (ELP) e escarificação em área total (EAT), em Latossolo e em Argissolo, localizados nos municipios de Guariba e Monte Alto, respectivamente. Para atender ao primeiro objetivo, avaliaram-se a emissão de CO2, a temperatura do solo (Tsolo) e a umidade do solo (Usolo) ao longo de 12 dias no Latossolo e em 11 dias no Argissolo, na camada de 0-0,10 m de profundidade. No Latossolo, não foi observado correlação entre a emissão de CO2, tanto com a Usolo como para Tsolo. No Argissolo, a emissão de CO2 foi correlacionada à Usolo, tanto no solo sob ELP (R2 = 0,86) quanto no solo sob EAT (R2 = 0,58). As emissões totais de CO2 no período de estudo foram maiores no Latossolo, no solo sob escarificação em linha de plantio e em área total (ELP = 1,042.6 kg CO2 ha-1 e EAT = 1,336.3 kg ha-1 de CO2), e menores no Argissolo (ELP = 659,1 kg CO2 ha-1 e EAT = 702,8 kg CO2 ha-1). No Latossolo, a emissão de CO2 foi menor no solo sob preparo com escarificação somente na linha de plantio do que no solo sob preparo com escarificação em área total. No Argissolo, a emissão de CO2 não diferiu em função do preparo. Para atender ao segundo objetivo, além de avaliar a emissão de CO2, temperatura e umidade do solo, avaliaram-se também a distribuição do tamanho de poros, o carbono orgânico associado aos minerais (COAM) e o carbono orgânico particulado (COP) na camada de 0-0,10 m de profundidade. No Latossolo, somente as propriedades: emissão de CO2, COP e classe de poro C4 (ɸ ≤ 0,04 mm) diferiram em função da escarificação. O modelo de regressão múltipla explicou 72% da variabilidade da emissão de CO2 no solo submetido a ELP para o COAM e C2 (0,05 < ɸ ≤ 0,1 mm). No Argissolo, a emissão de CO2, temperatura, umidade do solo, COAM, COP e as classes de tamanho de poros não diferiram em função das escarificações. Na regressão múltipla, a umidade do solo, C1 (ɸ ≥ 0,1 mm) e o COAM explicaram, juntas, 82% da variabilidade da emissão de CO2 no solo sob ELP. No Latossolo, a escarificação em linha de plantio e em área total afetaram diretamente a estrutura do solo, causando mudanças na porosidade e alterações na emissão de CO2 do solo. No Argissolo, a escarificação em linha de plantio e em área total não afetaram a emissão de CO2. / The chiseling operations alters the soil structure and affects the dynamics of the soil CO2 emission in a short period of time. Thus, the aim of this study was to: i- Investigate the temporal variation of CO2 emission after chiseling for the planting of sugarcane in Latossolo and Argissolo, ii – Characterize and correlation the soil CO2 emission and pore distribution in Latossolo and Argissolo with chiseling at line and total area to sugarcane planting. The experimental design used was in paired large plots. The treatments consisted of chiseling at the planting line (ELP) and chiseling at total area (EAT) in Latossolo and Argissolo, located in the municipalities of Guariba and Monte Alto, respectively. In order to attend the first aim, the CO2 emission, temperature and soil moisture were observed for 11 and 12 days, respectively at Argissolo and Latossolo, in the 0-0.10 m depth layer. The Latossolo did not show relationship among CO2 emission, Usoil and Tsoil to both chiseling. However, the Argissolo showed a significant relationship between the CO2 emission and Usoil to both chiseling, ELP (R2 = 0.86) and EAT (R2 = 0.58). The total CO2 emission was higher at Latossolo in both chiseling (ELP = 1,042.6 kg CO2 ha-1 and EAT = 1,336.3 kg ha-1 CO2) when compared with the Argissolo (ELP = 659.1 kg CO2 ha-1 and EAT = 702.8 kg CO2 ha-1). In the Latossolo, CO2 emission was lower in the soil under preparation with chiseling only in the planting line than in the soil under preparation with chiseling in the total area. In the Argissolo, the CO2 emission did not differ according to the preparation. In order to attend the second aim, the CO2 emission, temperature and soil moisture were also observed. Moreover, the distribution of pores size, organic carbon associated with minerals (COAM) and particulate organic carbon (COP) were also evaluated, in the 0-0.10 m depth layer. To Latossolo, the CO2 emission, COP and the distribution of pores size (C4; ɸ ≤ 0.04 mm) had significate difference between the chiseling. The multiple regression model was able to explain 72% of the CO2 emission variability to COAM and C2 (0.05 <ɸ ≤ 0.1 mm) at soil under ELP. To Argissolo, the CO2 emission, temperature, soil moisture, COAM, COP and distribution of pores size were not different between the chiseling. The soil moisture, C1 (ɸ ≥ 0,1 mm) and COAM were able to explain 82% of CO2 emission variability at soil under ELP. Therefore, the chiseling affected the soil porosity and soil CO2 emission directly at Latossolo. However, the chiseling did not affect the soil CO2 emission at Argissolo.
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Mapping soil organic carbon storage in deep soil horizons of Amazonian Podzols / Mapeamento do estoque de carbono orgânico em horizontes profundos de Espodossolos da AmazôniaOsvaldo José Ribeiro Pereira 19 January 2016 (has links)
The Podzols of the world are divided into intra-zonal and zonal according to then location. Zonal Podzols are typical for boreal and taiga zone associated to climate conditions. Intra-zonal podzols are not necessarily limited by climate and are typical for mineral poor substrates. The Intra-zonal Podzols of the Brazilian Amazon cover important surfaces of the upper Amazon basin. Their formation is attributed to perched groundwater associated to organic matter and metals accumulations in reducing/acidic environments. Podzols have a great capacity of storing important amounts of soil organic carbon in deep thick spodic horizons (Bh), in soil depths ranging from 1.5 to 5m. Previous research concerning the soil carbon stock in Amazon soils have not taken into account the deep carbon stock (below 1 m soil depth) of Podzols. Given this, the main goal of this research was to quantify and to map the soil organic carbon stock in the region of Rio Negro basin, considering the carbon stored in the first soil meter as well as the carbon stored in deep soil horizons up to 3m. The amount of soil organic carbon stored in soils of Rio Negro basin was evaluated in different map scales, from local surveys, to the scale of the basin. High spatial and spectral resolution remote sensing images were necessary in order to map the soil types of the studied areas and to estimate the soil carbon stock in local and regional scale. Therefore, a multi-sensor analysis was applied with the aim of generating a series of biophysical attributes that can be indirectly related to lateral variation of soil types. The soil organic carbon stock was also estimated for the area of the Brazilian portion of the Rio Negro basin, based on geostatistical analysis (multiple regression kriging), remote sensing images and legacy data. We observed that Podzols store an average carbon stock of 18 kg C m-2 on the first soil meter. Similar amount was observed in adjacent soils (mainly Ferralsols and Acrisols) with an average carbon stock of 15 kg C m-2. However if we take into account a 3 m soil depth, the amount of carbon stored in Podzols is significantly higher with values ranging from 55 kg C m-2 to 82 kg C m-2, which is higher than the one stored in adjacent soils (18 kg C m-2 to 25 kg C m-2). Given this, the amount of carbon stored in deep soil horizons of Podzols should be considered as an important carbon reservoir, face a scenario of global climate change / Os Espodossolos podem ser divididos em zonais e intrazonais de acordo com área onde ocorrem. Os Espodossolos zonais são típicos de áreas boreais e taiga, delimitados por condições climáticas. Já os intrazonais não são condicionados pelo clima. Os Espodossolo intrazonais brasileiros ocupam uma grande extensão da alta bacia amazônica, tendo sua formação atribuída à ocorrência de lençóis freáticos suspensos associados à acumulação de complexos organometálicos em ambientes ácidos redutores. Esses solos tem a capacidade de estocar grandes quantidades de carbono orgânico em horizontes espódicos profundos (Bh), em profundidades que podem variar de 1,5m a 5m. Pesquisas atuais relacionadas ao estoque de carbono em solos amazônicos, não levam em consideração os estoques encontrados no horizonte Bh (abaixo de 1m de profundidade). Sendo assim, o principal objetivo da presente pesquisa foi quantificar e mapear o estoque de carbono nos solos da bacia do Rio Negro, tendo-se em vista aquele estocado no primeiro metro de solo, bem como o carbono armazenado em até 3m de profundidade. A quantidade de carbono orgânico estocado nos solos da bacia do Rio Negro foi estimada em diferentes escalas de mapeamento, desde mapas locais até a escala da bacia do Rio Negro. Imagens de sensoriamento remoto de alta resolução espacial e espectral foram essenciais para viabilizar o mapeamento dos solos nas áreas estudadas e permitir a estimativa do estoque de carbono. Uma análise multisensor foi adotada buscando-se gerar informações biofísicas indiretamente associadas à variação lateral dos tipos de solo. Após o mapeamento do estoque de carbono em escala regional, partiu-se para a estimativa na escala da bacia do Rio Negro, com base em análise geoestatística (krigagem por regressão linear), imagens de sensoriamento remoto e base de dados de domínio público. Após o mapeamento do estoque de carbono na escala da bacia, constatou-se que os Espodossolos têm um estoque médio de 18 kg C m-2, para 1m de profundidade, valor similar ao observado em solos adjacentes (Latossolos e Argissolos) os quais tem um estoque de 15 kg C m-2. Quando são considerados os estoques profundos, até 3m, a quantidade de carbono dos Espodossolos é superior com valores variando de 55 kg C m-2 a 82 kg C m-2. Estoque relativamente maior que aquele observado em solos adjacentes para esta profundidade (18 kg C m-2 a 25 kg C m-2). Portanto, o estoque de carbono profundo dos Espodossolos, não deve ser negligenciado levando-se em conta cenários futuros de mudanças climáticas
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Sustainable mangement of natural rangeland ecosystemsMontenegro-Ballestero, Johnny Unknown Date
No description available.
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Estoques de carbono do solo em áreas de reflorestamento: bases para projetos de Mecanismo de Desenvolvimento Limpo / Soil carbon stocks in reforestation areas: bases for Clean Development ProjectsCindy Silva Moreira 09 November 2010 (has links)
Considerando a grande importância do seqüestro de carbono (C) nos solos florestais, observa-se pequena quantidade de projetos de MDL que incluem esse compartimento como agente da mitigação do aquecimento global. Isso ocorre pelo fato da quantificação dos estoques de C do solo representar maiores desafios se comparada aos demais componentes dos ecossistemas florestais. Sabendo-se das dificuldades econômicas e ambientais envolvidas na adoção desse tipo projeto e da importância das florestas na mitigação da mudança do clima, o objetivo desse trabalho foi avaliar o desempenho de metodologias para a obtenção do estoque de C do solo em duas áreas de reflorestamento e suas respectivas linhas de base (usos do solo anteriores aos plantios, i.e. pastagens e vegetações nativa), como base para diminuir a relação custo-benefício de projetos de MDL. Para alcançar o objetivo principal, a presente pesquisa foi composta das seguintes etapas: (i) estudo da variabilidade espacial do C do solo em uma área de reflorestamento com espécies nativas, estabelecida em Cotriguaçú/MT (Área I) e em uma cronossequência de plantio de eucalipto, localizada em Avaré/SP (Área II); (ii) determinação do tamanho da parcela e do nº ideal de amostras a partir da dependência espacial do C nos reflorestamentos; (iii) estimativa dos teores de C e densidades do solo (Ds) pela Espectroscopia de Reflectância no Infravermelho Próximo (NIRS) e Médio (MIRS), visando a redução dos custos analíticos sem prejuízo da qualidade dos resultados; e (iv) cálculo dos estoques de C do solo nas áreas e estimativa do balanço de carbono do projeto de MDL conduzido na Área II, utilizando a ferramenta EX-ACT (Ex-Ante Carbon Balance Tool). Os resultados obtidos confirmaram a existência de importante variabilidade espacial do C do solo nas áreas e dependência espacial forte em todos os sistemas de manejo estudados. A análise do número ideal de amostras de solo indicou que a coleta de cinco pontos por parcela é tão precisa quanto uma amostragem com mais pontos. O tamanho ideal das parcelas variou de 361-841 m2 nos plantios da Área I e de 900-3721 m2 nos plantios da Área II. O desempenho dos métodos NIRS e MIRS na estimativa do teor de C dos solos foi bastante satisfatório, principalmente quando os modelos testados foram calibrados com quantidades entre 5-10% do conjunto de dados total. Os resultados da estimativa da Ds foram um pouco inferiores aos do C. Os estoques de C do solo obtidos na Área I foram superiores aos da Área II. Considerando apenas o solo, é possível afirmar que o potencial de geração de créditos de C é maior no reflorestamento com espécies nativas sob solo argiloso do que no reflorestamento com eucalipto em solo arenoso. O balanço de C do projeto conduzido na Área I indicou o seqüestro de quase três milhões de toneladas de CO2eq em 40 anos. Espera-se que este estudo contribua para o aumento da inclusão do solo em projetos de MDL, uma vez comprovada a possibilidade de redução dos custos associados à obtenção e determinação dos estoques de C nesse compartimento / Considering the great importance of carbon sequestration (C) in forest soils, there are few CDM projects that include this compartment as an agent of global warming mitigation. This occurs because the quantification of soil C stocks represents a bigger challenge when compared to other components of forest ecosystems. Considering the economic difficulties and environmental issues involved in adopting this type of project and the importance of forests in mitigating climate change, the objective of this study was to evaluate the performance of methods for obtaining soil C stocks in two forestry areas and their respective baselines (land use prior to planting, i.e. pastures and native vegetation) as a basis for reducing the cost-benefit ratio of CDM projects. To achieve the main objective, this research was composed of the following steps: (i) estimating the spatial variability of soil C in an area reforested with native species, established in Cotriguaçú, MT (Area I) and a Eucalyptus chronosequence, located in Avaré, SP (Area II), (ii) determining the optimal amount of soil samples and the plot size from the soil C spatial dependence range in the reforestation areas, (iii) estimating soil C content and bulk density (BD) by Near and Mid Infrared Reflectance Spectroscopy (NIRS and MIRS, respectively) to reduce analytical costs without affecting the quality of the results, and (iv) calculating soil C stocks in both areas and estimating the carbon balance of a CDM Project conducted in Area II, using EX-ACT (\"Ex-Ante Carbon Balance Tool\"). The results confirmed the existence of significant soil C spatial variability in both areas and a strong spatial dependence at all plots. The analysis of the optimal number of soil samples indicated that the sampling procedure with five points per plot is as accurate as intensive sampling. The optimum size of plots ranged from 361-841 m2 at Area I plantations and from 900-3721 m2 at Area II. The performance of MIRS and NIRS to estimate the soil carbon content was very satisfactory, especially when the models were calibrated with amounts between 5-10% of the total data set. The estimations of BD were slightly less precise than those of soil C content. The soil C stocks obtained at Area I were higher than Area II. Considering only the soil compartment, it is clear that the potential for C credit generation in a reforestation with native species on a clayey soil is higher than in a reforestation with eucalyptus on a sandy soil. The C balance of the CDM project conducted in Area I is expected to sequester almost three million tones of CO2 eq in 40 years. We hope this study contributes to the increased inclusion of soil in CDM projects, by confirming the feasibility of reducing the costs associated with both sampling and analytical procedures
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