TPC is a 16 000 hectare estate located in Moshi, Tanzania and is currently planted under 8 800 hectares of sugarcane and produces over 60 000 tons of sugar per annum. The influence of volcanic parent material and volcanic ash over TPC, together with the alluvial nature of many of the soils, has imparted a unique combination of soil mineralogical, physical and chemical properties. Furthermore, irrigation with poor quality water has led to sodicity problems on the estate. Understanding the mineralogy and sodicity effects on soil hydraulic properties across the estate can lead to better irrigation management where it is important to prevent the build-up of salts due to over-irrigation. In response to this need, a study was carried out with the aim of characterising the mineralogical, physical and chemical properties in the five management areas of the estate (North, East, West, South and Kahe), in order to determine the relationships between various measured parameters. A total of 70 fields across TPC, as well as four sites outside the estate and two ash layers, were chosen for sampling. Undisturbed soil cores and bulk samples were collected from the A and B horizons from 45 of these fields and the four sites outside. Selected fields were sampled at more than one site to assess field variability, and where cane growth was patchy selected fields were sampled in a patch of poorly growing cane and an adjacent patch of better cane growth. Bulk soil samples were collected from the remaining fields and the two ash layers. Double ring infiltration measurements were carried out on 25 of the selected fields. X-ray diffraction, transmission electron microscopy and aluminium, iron and silica extractions were carried out to determine the mineralogy. Physical and chemical measurements included water retentivity, saturated hydraulic conductivity, bulk density, particle size distribution, organic carbon, pH (H2O), electrical conductivity, water soluble and exchangeable cations (Ca, Mg, K and Na), cation exchange capacity and clay specific surface area. The particle size distribution showed that the soils were mainly loams and sandy loams. Organic carbon values were generally greater in the A horizon compared to the B horizon and varied between 0.4 and 2.5 % in the topsoil and 0.3 and 2.1 % (with the exception of field 11 which had an organic carbon of 4.0 %) in the subsoil. X-ray diffraction patterns of sand and silt fractions were dominated by sanidine while clay patterns were weak and had high backgrounds and very broad peaks, suggesting the presence of poorly ordered material in the clay fraction. The Al and Fe extraction methods and electron micrographs indicated that this poorly ordered material was allophane. However, the dominant clay mineral across the estate was halloysite, in both tubular and spheroidal form, as well as very small (<< 0.5 μm) kaolinite particles. There was also gibbsite in some of the samples analysed. The combination of allophane, halloysite, kaolinite and gibbsite indicated that the primary volcanic minerals have weathered to various degrees across the estate. This is reflected in the alluvial nature of the soils where less weathered material has been periodically deposited onto older, more weathered material over some parts of the estate. The south and west areas had a slightly higher Alo + ½ Feo ratio than the other areas in both the topsoil (1.07 and 0.95, respectively) and the subsoil (1.16 and 1.06, respectively), a possible consequence of less weathered alluvial material that was deposited in these areas. Although the concentration of allophane was low (< 5 %), even in the south and west areas, its presence greatly increased the clay specific surface area (up to 145.94 m2 g-1) and consequently had a significant influence on the soil physical and chemical properties. Water retention across TPC was high, particularly at the lower matric potentials (between 0.13 and 0.45, and 0.09 and 0.24 m3 m-3 at -33 kPa and -1500 kPa, respectively). The high water retention is a result of allophane which gives the soils a high adsorption capacity and a porosity that is dominated by micro-pores. Generally, the south area had the highest water retention at the various measured matric potentials which corresponds to the higher allophane content. Variability in water retentivity across areas and within fields limited further interpretation and correlation with the mineralogical results. Infiltration rate was lowest in the south (60.85 mm hr-1) and highest in the Kahe area (171.20 mm hr-1). The main factor influencing the final infiltration rate was the concentration of sodium in the soil, with higher concentrations causing soil dispersion and blockage of soil pores. Clay dispersion has led to the development of calcareous surface crusts and reduced porosity, thus reducing the infiltration rate. Sodium concentration in the soil is likely to have had a dominating effect over the mineralogical composition of the soil. Poor cane growth in the south and west areas corresponded to higher pH (up to 10.32), electrical conductivity (up to 614 mS m-1), sodium absorption ratio (up to 20.63) and water soluble and exchangeable sodium (up to 53.20 mmolc l-1 and 14.87 cmolc kg-1 soil, respectively) in these areas. The soils are thus more dispersive and the combination of sodicity and allophane has resulted in “fluffy” soils with small particles clogging soil pores and thus surface crusts have formed easily. The combined effect of mineralogy and sodicity in the south is further complicated by the presence of perched water tables. High adsorption capacities and the dominance of micro-pores allow the occurrence of significant capillary rise which brings salts to the soil surface, further exacerbating the sodicity problem. Therefore, over-irrigation should be avoided where soils are prone to sodicity from a combination of irrigation with poor quality water, perched water tables and strong capillary rise action. Fields which are currently experiencing the negative effects of high sodicity, require irrigation with good quality water and adequate sub-surface drainage to ensure the leaching of salts. Further studies with specific focus on the south and west areas would be beneficial in accounting for the variability and in drawing correlations between the mineralogy and sodium content of the soils with the other measured properties. Fields which are prone to increased sodicity through over-irrigation with poor quality water, have strong capillary rise from perched water tables and which require remediation through sub-surface drains can thus be distinguished and the factors influencing sugarcane growth can be more clearly understood. Growth depends on the combination of these soil’s unique mineralogy and sodium content and the influence they have on the infiltration rate, adsorption capacity, micro-porosity and capillary rise from the water table. For future work, water movement modelling to predict saturated and unsaturated flow, as well as in situ measures of unsaturated flow, will lead to further understanding of the soil hydraulic properties and aid in improved irrigation management. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-11, Section: B, page: 7521. Adviser: Julie L. Zilles. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--University of Western Australia, 2007.

Thesis (M.Sc.)(Plant Science))--University of Pretoria, 2008. / Includes bibliographical references.

Soil physical and chemical properties determine a soil's crop production potential and the sustainability of a production system. The objective of this study was to determine the effect of solid and liquid pig manure application on the physical and chemical properties of soil after 5 years of manure application. Solid pig manure increased saturated hydraulic conductivity (Ksat) by 110%, aggregate stability by 30%, available and total phosphorus by 471% and 52% respectively, available nitrogen by 38%, organic carbon by 29% and exchangeable K by 308%, and reduced soil bulk density by 14%. Liquid pig manure (LPM) also increased aggregate stability by 21%, exchangeable K by 45%, available P and total P by 258% and 27%, respectively and, reduced bulk density by 6%. An important finding was the 33% decrease in the concentration of exchangeable Ca in LPM-amended soils. Significant manure by cropping system interaction was also obtained for water retention parameters and available water, total nitrogen and electrical conductivity. There was no effect of pig manure on pH and exchangeable Mg concentrations. Soils under perennial vegetation had 31% greater Ksat, 26% increase in available N, 31% greater available P, 15% greater total P and 12% lower bulk density compared with those under annual crops. Our results show that SPM has a potential as a better organic amendment in improving physical and chemical properties of surface soils. / February 2016

Made available in DSpace on 2015-10-06T13:03:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-28. Added 1 bitstream(s) on 2015-10-06T13:18:11Z : No. of bitstreams: 1 000848895.pdf: 1016755 bytes, checksum: 1dfa629d467a6bc591e92c2f0ae8673a (MD5) / No sistema de pousio, o solo é deixado em repouso por um período de tempo muito variável para que o pool de matéria orgânica do solo se recupere e se assemelhe ao encontrado em florestas maduras adjacentes. Para comprovar tal prática foi realizada uma prospecção no Povoado Quilombo de Damásio, Município de Guimarães, Estado do Maranhão onde obteve-se amostras do solo em áreas de pousio com 25, 20, 15, 10, e 5 anos; da área atual cultivada (lavoura) e outra de floresta primária (controle) nas camadas de 0 a 20 e 20 a 40 cm. O sistema de pousio, nas duas profundidades e tempos, apresentou aumentos e perdas de macronutrientes. Pela análise estatística observou-se diferenças significativas nos aportes e perdas de macronutrientes entre os tratamentos (tempos de pousios) nas duas profundidades do solo analisadas. A análise de correlação apresentou associação positiva e negativa para os macronutrientes pesquisados (P, K+, Ca2+ e Mg2+). Ao longo do tempo o sistema de pousio mostrou-se eficiente na recuperação da fertilidade natural do solo / In the fallow system, the soil is left undisturbed for a very variable period of time so that the pool of soil organic matter recovers and resembles that found in adjacent mature forests. To prove this practice was carried out a survey in the town of Quilombo Damásio, City of Guimaraes, Maranhao State where soil samples were obtained in fallow areas 25, 20, 15, 10, and five years; the current cultivated area (farming) and other primary forest (control) in the layers 0-20 and 20 to 40 cm. The fallow system at both depths and times, showed increases and macronutrient losses. For the statistical analysis we observed significant differences in contributions and loss of nutrients between treatments (fallow times) in both soil depths analyzed. The correlation analysis showed a positive association and negative for respondents macronutrients (P, K+, Ca2+ and Mg2+). Over time the fallow system was efficient in the recovery of natural soil fertility

Made available in DSpace on 2014-06-11T19:26:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-17Bitstream added on 2014-06-13T18:54:16Z : No. of bitstreams: 1 almeida_vc_me_rcla.pdf: 529540 bytes, checksum: d275b5b8080e8d5cd9bae917fbc719bf (MD5) / Este trabalho apresenta aspectos relevantes para a implementação de projeto de MDL e PSAs em áreas naturais e cultivadas para empresas privadas, órgãos governamentais, organizações não-governamentais e sociedade civil que buscam bases técnicas-científicas com vistas ao desenvolvimento sustentável. O carbono orgânico no solo está principalmente sob forma de matéria orgânica humificada e sua quantidade e qualidade são influenciadas pelos fatores de formação do solo. A geomorfologia atua no condicionamento do solo e o clima age através do intemperismo, que transforma os elementos e a matéria orgânica humificada. O estudo analisou a distribuição do carbono orgânico nos compartimentos morfológicos do Estado de São Paulo. Os resultados indicaram que os maiores teores de carbono orgânico no solo (pontos discrepantes > 3.8%) relacionam-se às regiões que apresentam condições geomorfológicas propícias à deposição de sedimentos, como planícies de inundação e depressões côncavas, indicando relação com eventos pretéritos de evolução das paisagens aliados às condições climáticas de manutenção da matéria orgânica. As áreas planálticas, com solos mais jovens, também apresentam teores relativamente alto de carbono orgânico (%). A integração geossistêmica do compartimento solo com a geomorfologia constitui importante subsídio para propostas de seqüestro de carbono em projetos de MDL e PSAs, considerando o solo tanto como corpo principal da análise como também associado à cobertura vegetal no seqüestro de carbono. A determinação do carbono no solo para projetos de seqüestro/retenção deve empregar métodos de quantificação complementares, a fim de considerar as diferentes formas de carbono para contabilidade. / This study shows relevant aspects to implement CDM and PES in natural and cultivated areas for private enterprises, governmental offices NGOs and the society, all which search for technical-cientific basis for sustainable development. Organic carbon in the soil is mainly presented under the form of humic organic matter, and its quantity and quality are influenced by the same factors of soil formation. Geomorphology acts in soil conditioning and the climate, through weathering, acts in the formation and evolution of soils, as well as on humic organic matter. The aim of this study was to analyze the distribution of organic carbon on morphologic compartiments in the State of São Paulo, Brazil. The results showed that the highest rates of organic carbon in the soil (outliers > 3.8%) related to the regions that presents geomorphologic conditions which were suitable to sediment depositions, such as inundated plains and depressions, indicating a relationship with the past evolution events of landscape and climate conditions to preserve the organic matter in sois. The planaltic areas with young soils also showed relatively high rates of organic carbon. The geosystemic integration of soils compartments with the geomorphology constituted an important subside for carbon capture proposals in the Clean Development Environmental (CDM) and Payment for Environmental Services (PES); considering the soil either as main compartment of analysis or associated with vegetations in carbon capture. To determine carbon quantity in the soil or retention, complementary quantifying methods must be used in order to consider the different form of counting carbon.

Made available in DSpace on 2014-06-11T19:27:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-21Bitstream added on 2014-06-13T20:36:22Z : No. of bitstreams: 1 rossin_bg_me_rcla.pdf: 847890 bytes, checksum: 3483f5f5a422925fc749b5a97465490b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O propósito do estudo foi compreender a significação da evolução de uma microbacia de águas escuras e da dinâmica da matéria orgânica para o aparecimento e manutenção das águas escuras de tal microbacia, no alto Rio Negro. O objetivo, então, foi estudar a distribuição e as mudanças na natureza da matéria orgânica presente nos solos no decorrer da evolução da microbacia de águas escuras e estudar a evolução pedo-geomorfológica desta bacia. A pesquisa apoiou-se no estudo morfológico dos solos; no levantamento e elaboração de mapa pedo-topográfico; na verificação da diferenciação das matérias orgânicas ao longo da micro-bacia, e na investigação do processo de humificação dos solos. interpretação de imagem satélite seguida prospecção campo. Três trabalhos de campo foram suficientes para: 1) escolha da microbacia a ser estudada; 2) estudo dos solos em campo e levantamento topográfico para realizar o mapeamento dos solos; 3) coleta de amostras de solos e checagem do mapeamento. A morfologia dos solos foi descrita em perfis, em trincheiras abertas para esse fim, alinhadas em uma transeção NW-SE, adaptando-se os procedimentos da Análise Estrutural da Cobertura de Solos (BOULET et. al, 1982). As amostras coletadas foram preparadas para a realização dos diferentes procedimentos em laboratório: análise textural; extração de argila para análises de C orgânico N e H; pré-tratamento das amostras com citrato-bicabonato-dithionito (CDB); análise elementar de carbono, hidrogênio e nitrogênio da amostra total e das argilas; determinação dos grupos funcionais da matéria orgânica por infravermelho com transformada de Fourier (FT-IR); análise por fluorescência induzida por laser (FIL) para obtenção do grau de humificação. Os resultados obtidos revelaram que a evolução da microbacia estão... / The purpose of the study was to understand the importance of the evolution of a micro-basin in dark waters and the organic matter dynamics for the appearance and maintenance of such dark waters of this micro-basin, in the upper Rio Negro. The goal then was to study the distribution and changes of organic matter nature in soils during the evolution of the watershed dark waters and to study the pedo-geomorphological evolution of this basin. The research was supported by the morphological study of soils; survey and development of pedo-topographic map; verifying the differentiation of organic matter along the micro-basin, and in the investigation of the soil humification process. The study site was chosen based on the interpretation of satellite imagery followed by prospecting field. Three field studies were adequate to: 1) choosing the studied watershed , 2) studying of soils in the field and surveying to perform the soils mapping , 3) collection of soil samples and mapping check. The soil morphology was described in profiles, in open trenches for this purpose, aligned in a NW-SE transect, adapting the procedures of the Structural Analysis of the Soil-Landscape (Boulet et. al, 1982). The samples were prepared to carry out the different procedures in the laboratory: textural analysis, clay extraction for analysis of organic C, N and H; pre- treatment of samples with citrate-dithionite -bicarbonate (CDB); carbon hydrogen and nitrogen analysis, from the total sample and clays; determination of the organic matter functional groups by Fourier Transform Infrared (FT-IR); analysis by fluorescence induced laser (FIL) in order to achieve the degree of humification. The results revealed that the watershed evolution is closely tied to the development and evolution of podzolization and to the drainage installation . Also, to the... (Complete abstract click electronic access below)

Orientador: Marcílio Vieira Martins Filho / Coorientador: José Marques Júnior / Banca: Gener Tadeu Pereira / Banca: Carlos Eduardo Angeli Furlani / Banca: Milton Cesar Costa Campos / Banca: Alan Rodrigo Panosso / Resumo: O avanço tecnológico e o desenvolvimento da agricultura têm aumentado a demanda por informações detalhadas dos solos e seus atributos. O presente trabalho teve como objetivos identificar a ocorrência de solos coesos e estudar suas relações com a paisagem, bem como predizer a erodibilidade de Argissolos coesos na região leste do Estado do Maranhão, em diferentes pedoformas, por meio da determinação dos componentes da cor do solo, utilizando a espectroscopia de reflectância difusa. Foram abertas três trincheiras (perfis 1, 2 e 3), relacionadas a três distintas formações vegetais, para a caracterização morfológica, física, química e mineralógica. Para a predição da erodibilidade, foram selecionadas três áreas cultivadas com soja, onde de cada área, foram retiradas 121 amostras na profundidade de 0,00 - 0,20 m. Para a determinação da reflectância difusa na faixa do visível (380 a 780 nm), foi utilizado 0,5 g de cada amostra, moída e seca ao ar, a partir do qual foram determinados os valores do matiz, valor e croma. De posse destes constituintes da cor, foi calculado o índice de avermelhamento para cada amostra. Foram desenvolvidos modelos para avaliar o efeito de cada componente da cor sobre a erodibilidade em entressulcos (Ki) e em sulcos (Kr), que apresentaram R2 variando de 0,37 a 0,70. Os modelos gerados quando comparados ao de Flanagan e Livingston obtiveram R2 de 0,70 e 0,73, para Ki e Kr, respectivamente. Os resultados demonstraram que a caulinita foi o mineral predominante nos horizontes coesos, porém seu grau de cristalinidade não influenciou na variação da densidade do solo (1,40 a 1,58 g cm-3) e na resistência à penetração (0,68 a 2,18 MPa). A posição da paisagem foi determinante para a distinção dos solos coesos, sendo aqueles desenvolvidos em pedoforma côncava os que apresentaram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Technological advances and the development of agriculture has increased the demand for detailed soil and its attributes. This study aimed to identify the occurrence of cohesive soils and relationship with its properties with the landscape to predict the erodibility by Ultisols cohesive in the region east of State Maranhão, different landforms using components of soil color characterized by diffuse reflectance spectroscopy. Three trenches were dug (depth profiles 1, 2 and 3) related to three distinct vegetation types, for morphological, physical, chemical and mineralogical. For predicting erodibility selected three areas cultivated with soybeans, those areas 121 soil samples were taken in depth from 0,00 to 0,20 m. 0,5 g of each sample, milled and air dried, values were determined from reflectance in the visible range (380 - 780 nm), from which was determined the values of hue, chroma values. From these spectro components, we calculated the redness index for each sample. Models were developed to evaluate the effect of each component of the color on the erodibility interrill (Ki) and grooves (Kr), showed that R2 ranging from 0,37 to 0,70. The models compared to Flanagan and Livingston obtained R2 of 0,70 and 0,73 for Ki and Kr, respectively. The results demonstrated the kaolinite was the predominant mineral in cohesive layers, but its degree of crystallinity did not influence the changes in soil density (1,40 to 1,58 g cm-3) and penetration resistance (0,68 to 2,18 MPa). The landscape position was essential to the distinction of cohesive soils, and those established in concave landform presented the highest expression of the cohesive character, which resulted in higher soil fertility and organic matter reflecting the more exuberant vegetation characterized by Cerradão. That the constituents of the color thus obtained... (Complete abstract click electronic access below) / Doutor

Orientador: Nádia Regina do Nascimento / Banca: Guilherme Taitson Bueno / Banca: Débora Marcondes Bastos Pereira Milori / Resumo: O propósito do estudo foi compreender a significação da evolução de uma microbacia de águas escuras e da dinâmica da matéria orgânica para o aparecimento e manutenção das águas escuras de tal microbacia, no alto Rio Negro. O objetivo, então, foi estudar a distribuição e as mudanças na natureza da matéria orgânica presente nos solos no decorrer da evolução da microbacia de águas escuras e estudar a evolução pedo-geomorfológica desta bacia. A pesquisa apoiou-se no estudo morfológico dos solos; no levantamento e elaboração de mapa pedo-topográfico; na verificação da diferenciação das matérias orgânicas ao longo da micro-bacia, e na investigação do processo de humificação dos solos. interpretação de imagem satélite seguida prospecção campo. Três trabalhos de campo foram suficientes para: 1) escolha da microbacia a ser estudada; 2) estudo dos solos em campo e levantamento topográfico para realizar o mapeamento dos solos; 3) coleta de amostras de solos e checagem do mapeamento. A morfologia dos solos foi descrita em perfis, em trincheiras abertas para esse fim, alinhadas em uma transeção NW-SE, adaptando-se os procedimentos da Análise Estrutural da Cobertura de Solos (BOULET et. al, 1982). As amostras coletadas foram preparadas para a realização dos diferentes procedimentos em laboratório: análise textural; extração de argila para análises de C orgânico N e H; pré-tratamento das amostras com citrato-bicabonato-dithionito (CDB); análise elementar de carbono, hidrogênio e nitrogênio da amostra total e das argilas; determinação dos grupos funcionais da matéria orgânica por infravermelho com transformada de Fourier (FT-IR); análise por fluorescência induzida por laser (FIL) para obtenção do grau de humificação. Os resultados obtidos revelaram que a evolução da microbacia estão... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of the study was to understand the importance of the evolution of a micro-basin in dark waters and the organic matter dynamics for the appearance and maintenance of such dark waters of this micro-basin, in the upper Rio Negro. The goal then was to study the distribution and changes of organic matter nature in soils during the evolution of the watershed dark waters and to study the pedo-geomorphological evolution of this basin. The research was supported by the morphological study of soils; survey and development of pedo-topographic map; verifying the differentiation of organic matter along the micro-basin, and in the investigation of the soil humification process. The study site was chosen based on the interpretation of satellite imagery followed by prospecting field. Three field studies were adequate to: 1) choosing the studied watershed , 2) studying of soils in the field and surveying to perform the soils mapping , 3) collection of soil samples and mapping check. The soil morphology was described in profiles, in open trenches for this purpose, aligned in a NW-SE transect, adapting the procedures of the Structural Analysis of the Soil-Landscape (Boulet et. al, 1982). The samples were prepared to carry out the different procedures in the laboratory: textural analysis, clay extraction for analysis of organic C, N and H; pre- treatment of samples with citrate-dithionite -bicarbonate (CDB); carbon hydrogen and nitrogen analysis, from the total sample and clays; determination of the organic matter functional groups by Fourier Transform Infrared (FT-IR); analysis by fluorescence induced laser (FIL) in order to achieve the degree of humification. The results revealed that the watershed evolution is closely tied to the development and evolution of podzolization and to the drainage installation . Also, to the... (Complete abstract click electronic access below) / Mestre