It is generally assumed that increased map precision (ie map unit homogeneity) and map purity (map unit accuracy) should result from increasing the scale of mapping of the soil resource, since it should enable a more intricate breakdown of the landscape into landform facet based units. This study compared the predictive success of a 1:1 OK scale soil association map with the 1:25K and 1:1OOK scale soil landscape maps within the Birrigai area of the Paddy's river catchment, south west of Canberra, A.C.T. The 1:25K and the 1:100K scale soil landscape maps were also evaluated in a second larger evaluation area in the Paddy's river catchment which allowed more of the larger soil landscape map units to be evaluated. The 1:25K scale soil map was produced by another author for the A.C.T Government, and was surveyed at a substantially lower survey intensity than that for the 1:100K and 1:10K scale soil maps (ie only 0.05 observation sites / cm2 of published map). These maps were evaluated using a set of randomly located independent evaluation sites in each evaluation area, and from these calculating and comparing standard Marsman & de Gruijter(1986) measures of Map Purity. The strength of soil-landscape relationships within this catchment were determined from a Fixed One Way Analysis of Variance, and from more simplistic graphical comparisons of the means and standard deviations of the discrete soil data within these landform based map units. Soil-landscape relationships for the Nominal scale soil data (ie class type data) were evaluated by comparing the Marsman & de Gruijter(1986) Homogeneity index ratings among the soil map units. Intensive survey traverses were also carried out in selected soil landscapes to further evaluate the strength of soil landscapes present. The results revealed obvious improvements in map quality associated with increasing map scale from 1:100,000 to 1:10,000, and these included increases in the predictive success (Map Purity), reductions in the extent of map unit impurities, and planning advantages associated with having individual land facets delineated on the 1:10,000 scale map. The respectable purity ratings achieved by the 1:100,000 scale soil landscape map (ie average purity rating of 63%) was largely attributed to the flexibility of the "soil material" approach to soil landscape mapping. The relatively poor performance of the 1:25K consultancy soil landscape map demonstrated the fact that; any benefit gained from the improved intricacy in the representation of map unit delineation's with increased mapping scale, will be drastically reduced if it is not matched by an associated increase in the intensity of field investigations. Evaluations of the soil-landscape relationships found that the land facets of the Paddy's river catchment generally failed to delineate areas that were both uniform and unique in respect of their soil properties. Soil-landscape relationships were instead found to be quite complex, applying to only certain land facets, and in regards to only certain soil properties. Soil maps with units based on landsurface features were recommended on the basis of the importance of other landscape factors other than soils to land capability ratings, as well as on the useability of such maps. This study recommended the adoption of a " >2 detailed soil profile observations / land facet in each map unit " mapping standard to ensure a reasonable estimate of the variability and modal soil conditions present, as well as a reliable confirmation of the perceived soil-landscape relationships. The error usually associated with small scale mapping was effectively reduced by rapid ground truthing, involving driving along the major roads dissecting the map area and making brief observations of soil exposures on road batters, despite the bias of the road network making such mapping improvements uneven across the map. The major point to come from this study was the re-emphasising of the point that soil spatial variability has to be accepted as a "real landscape attribute" which needs to be accurately described and communicated to land users, and must not be considered as some sort of soil mapping failure. The fact that individual facets of the landscape rarely coincide with unique pockets of uniform and unique soils and soil properties must be considered simply an on the ground reality of nature, and not some mapping failure. It was thought that since other landscape factors (eg hillslope gradient) most often dominate the determination of land use suitability and capability, it is better to effectively describe the range and modal state of the soil conditions within such facets, then to attempt to extrapolate possible soil boundaries using geostatistical techniques which cut across such land facets, and may or may not correlate with real groupings of soil properties, depending on the spatial resolution of the soil variability distribution in the landscape. Even so the results of this investigation do put the validity of the physiographic terrain class mapping model as a predictor of soil traits under question, at least for the more complex landscape settings.

Os solos são vitais para todos os ecossistemas terrestres e deles depende a maior parte dos recursos para a manutenção dos seres vivos. Seu uso é importante para a agricultura e, para assim serem usados, é necessário conhecê-los, tanto como são como onde estão na paisagem. Esse conhecimento pode ser adquirido através de levantamentos de solos para os quais existem muitas limitações, como alta demanda financeira, elevado tempo para sua execução e subjetividade associada ao conhecimento tácito dos pedólogos. Por isso, são necessárias novas estratégias que auxiliem a execução de mapas de solos. Uma abordagem promissora é a identificação de unidades naturais do relevo em nível de detalhe, uma vez que é possível predizer a ocorrência de atributos e tipos de solos na paisagem quando associando as feições dos seus perfis com as de sua superfície. Diante disto, este trabalho objetiva testar procedimentos digitais para segmentação detalhada de elementos das encostas e relacioná-los com os atributos e classes taxonômicas de solos. Em uma área de estudo de 2.500 ha, situada na região de Piracicaba (SP), parâmetros geomorfométricos organizados hierarquicamente em regras em uma árvore de decisão foram utilizados para classificar, em escala detalhada (1:10.000), os cinco elementos da encosta (topo, ombro, meia-encosta, sopé coluvial e sopé colúvio-aluvial). Avaliou-se uma estratégia de análise de similaridade visando à identificação de agrupamentos de amostras de solos da mesma classe, a partir de diferentes conjuntos de variáveis. Essa segmentação digital mostrou que é possível explicitar a localização de cada um dos elementos da encosta e que neles dominam perfis de solos que se assemelham. Na maioria dos casos, essa semelhança pode ser comprovada com o uso tanto de análises convencionais como espectrais das amostras de solo coletadas até 1 m de profundidade. Essa classificação digital dos elementos da encosta pode auxiliar no mapeamento de solos detalhados e ultradetalhados (escalas 20.000 ou maiores). / Soils are vital for all terrestrial ecosystems and the majority of resources for maintenance of human beings depend on them. Their use is important for agriculture and, in order to be used in this manner, it is essential to know them, as well as how they are and where they are located in the landscape. This knowledge can be acquired through soil surveys, that have several limitations, such as high financial demand, time-consuming execution and subjectivity associated with the pedologists tacit knowledge. Considering this, new strategies are needed to support the elaboration of soil maps. One promising approach is the identification of detailed natural units of relief, since it is possible to predict the occurrence of attributes and types of soils in the landscape when associating the features of their profiles with those of their surface. Therefore, this research aims to test digital procedures for detailed segmentation of hillslope elements and to relate them to soil attributes and taxonomic classes. In a study area of 2,500 ha located in the Piracicaba (SP) region, geomorphometric parameters hierarchically organized into rules in a decision tree were used in order to classify, in a detailed scale (1:10,000), five hillslope elements (summit, shoulder, backslope, footslope and toeslope). A similarity analysis strategy was used to identify groupings of soil samples from the same class, from different sets of variables. This digital segmentation showed that it is possible to make explicit the location of each one of the hillslope elements, where similar soil profiles are dominant. In most cases, this similarity can be verified with the use of both conventional and spectral analyses of soil samples collected up to a depth of 1 m. This digital classification of hillslope elements can support 1st and 2nd order soil survey (scales 1:36,680 or greater).

A gênese, a química, a macro e micromorfologia dos solos desenvolvidos nos ambientes arenosos da planície costeira do Estado de São Paulo foram investigadas. Nesses ambientes, genericamente denominados de restinga, a podzolização é o processo pedogenético predominante, sendo os Espodossolos e Neossolos Quartzarênicos os solos mais comumente encontrados. Os municípios paulistas de Cananéia, Ilha Comprida e Bertioga foram selecionados para o desenvolvimento desta pesquisa devido à presença de diferentes unidades sedimentares, de vegetação remanescente e de solos, representativos da planície costeira do Estado de São Paulo. Nesses locais foram descritos e amostrados 31 perfis, muitos deles em cronosseqüência. A idade dos sedimentos e da matéria orgânica de horizontes cimentados selecionados (ortstein) também foram investigadas e, juntamente às análises químicas, incluindo procedimentos de dissolução seletiva do Fe e Al (DC, oxalato e pirofosfato para Fe e Al; NaOH, KCl, LaCl3 e CuCl2 para Al) e às micromorfológicas, permitiram concluir que: (a) os Espodossolos mais evoluídos e antigos, dotados de horizontes ortstein, podem ser considerados indicadores dos sedimentos pleistocênicos da Formação Cananéia das planícies costeiras quaternárias estudadas e, possivelmente, são paleossolos; (b) o tempo e o relevo foram os principais fatores de formação, condicionantes da diferenciação dos Espodossolos na paisagem; (c) os solos mais antigos, bem drenados devido às condições de relevo e dinâmica sedimentar (Ilha de Cananéia e Bertioga), apresentam grande variabilidade e diversidade de seus horizontes e atributos morfológicos, diferindo daqueles mais jovens e mal drenados, mais homogêneos, geralmente destituídos de horizonte Bs (Bertioga); (d) a química da maioria dos solos estudados são típicas daqueles já descritos para as áreas sob vegetação de restinga: baixas soma e saturação por bases, extremamente a fortemente ácidos, capacidade de troca de cátions dependente da matéria orgânica e saturada com Al trocável, aumento do carbono orgânico em profundidade; (e) o Al é o principal cátion envolvido na podzolização, sendo que suas formas ativas são: complexos de Alhúmus e compostos inorgânicos pouco cristalinos. Os primeiros predominam nos horizontes superficiais e horizontes espódicos hidromórficos; as formas inorgânicas se relacionam a alguns horizontes espódicos (Bs, Bh, Bhs e Bsm) situados na base de perfis bem drenados; (f) Al inorgânico pouco cristalino também foi extraído pelos reagentes pirofosfato e CuCl2, geralmente utilizados para avaliar Al unido à matéria orgânica; ao contrário, LaCl3 extraiu apenas as formas ativas da interação Al-húmus, sendo que KCl não incluiu todas essas formas reativas; (g) a decomposição de raízes in situ e, sobretudo, os processos de formação e transporte de complexos Al-húmus foram observados em alguns (decomposição de raízes) ou em todos os perfis estudados (complexos Al-húmus), originando os horizontes espódicos às expensas dos eluviais; (h) a imobilização desses complexos se dá por diferentes mecanismos: filtragem físicomecânica dos poros do solo, aumento do pH em profundidade, incorporação adicional de Al durante seu transporte e o efeito da absorção seletiva das raízes. Neste último processo, as raízes absorvem seletivamente água e nutrientes, segregando e precipitando ao seu redor os complexos Al-húmus da solução do solo, mobilizados dos horizontes superiores ou presentes nas águas de drenagem. / The genesis, chemistry and macro and micromorphology of soils developed on the sandy coastal plain of the São Paulo State were investigated. In these environments, often designated restinga, podzolization is the main pedogenetic process, being Spodosols and Quartzipsamments the soils most commonly found. Cananéia, Ilha Comprida and Bertioga cities were selected for the development of this research due to the representativeness of this environmental condition in the São Paulo State. In these environments 31 soil profiles were described and sampled, mainly in chronosequences. Age of sediments and of organic matter of cemented horizons (ortstein) were investigated as well. These data associated to the chemical analysis, including Fe and Al selective dissolution procedures (dithionite-citrate, oxalate and pyrophosphate for Fe and Al; NaOH, KCl, LaCl3 and CuCl2 for Al) and micromorphological analysis allowed the following conclusions: (a) the most developed Spodosols have ortstein horizons and can be considered indicators of sediments of Pleistocene age from the Cananéia Formation of the studied quaternary coastal plain and possibly are paleosols; (b) time and relief were the main soil formation factors responsible for differentiation of Spodosols on the landscape; (c) the oldest and well drained soils due to relief conditions and sedimentary dynamics (Cananéia and Bertioga) showed great variability and diversity of their horizons and morphological properties, differing from the youngest, poorly drained and more homogeneous Spodosols usually without Bs horizon (Bertioga). The youngest and well drained Spodosols (Ilha Comprida) showed an advanced degree of degradation; (d) the chemical properties of the studied soils are similar to other soils already described in the restinga: low in exchangeable bases, low in base saturation, strongly acidic, organic-matter dependent and Al-saturated CEC, increase in organic carbon with depth; (e) Al is main metal related to the podzolization process. The reactive forms of this element are Al-humus complexes and inorganic poorly crystalline compounds. Alhumus complexes predominate in the superficial and spodic, poorly drained horizons; the Alinorganic forms occur in some well drained spodic horizons (Bs, Bh, Bhs and Bsm) situated at the bottom of the well-drained soil profiles; (f) Al inorganic, poorly crystalline forms were extracted by pyrophosphate and CuCl2 reagents, usually used to determinate Al bound to organic matter; unlike, LaCl3 only extracted the reactive forms of Al-humus interaction, whereas KCl did not include these reactive forms; (g) Al-humus formation and mobilization were the main pedogenetic processes, but roots decomposition were observed in some horizons; (h) different mechanisms are related to Al-humus complexes immobilization: physical-mechanical filtering effect on soil pores, precipitation as pH increases with depth, precipitation with the decrease of C-to-metal ratio during organic matter complexation and roots selective absorption effect. In the latter, there is selective absorption of water and nutrients with segregation and precipitation of Al-humus complexes around roots. These Al-humus complexes are either mobilized from the superficial horizons or already dissolved in the draining water.

A gênese, a química, a macro e micromorfologia dos solos desenvolvidos nos ambientes arenosos da planície costeira do Estado de São Paulo foram investigadas. Nesses ambientes, genericamente denominados de restinga, a podzolização é o processo pedogenético predominante, sendo os Espodossolos e Neossolos Quartzarênicos os solos mais comumente encontrados. Os municípios paulistas de Cananéia, Ilha Comprida e Bertioga foram selecionados para o desenvolvimento desta pesquisa devido à presença de diferentes unidades sedimentares, de vegetação remanescente e de solos, representativos da planície costeira do Estado de São Paulo. Nesses locais foram descritos e amostrados 31 perfis, muitos deles em cronosseqüência. A idade dos sedimentos e da matéria orgânica de horizontes cimentados selecionados (ortstein) também foram investigadas e, juntamente às análises químicas, incluindo procedimentos de dissolução seletiva do Fe e Al (DC, oxalato e pirofosfato para Fe e Al; NaOH, KCl, LaCl3 e CuCl2 para Al) e às micromorfológicas, permitiram concluir que: (a) os Espodossolos mais evoluídos e antigos, dotados de horizontes ortstein, podem ser considerados indicadores dos sedimentos pleistocênicos da Formação Cananéia das planícies costeiras quaternárias estudadas e, possivelmente, são paleossolos; (b) o tempo e o relevo foram os principais fatores de formação, condicionantes da diferenciação dos Espodossolos na paisagem; (c) os solos mais antigos, bem drenados devido às condições de relevo e dinâmica sedimentar (Ilha de Cananéia e Bertioga), apresentam grande variabilidade e diversidade de seus horizontes e atributos morfológicos, diferindo daqueles mais jovens e mal drenados, mais homogêneos, geralmente destituídos de horizonte Bs (Bertioga); (d) a química da maioria dos solos estudados são típicas daqueles já descritos para as áreas sob vegetação de restinga: baixas soma e saturação por bases, extremamente a fortemente ácidos, capacidade de troca de cátions dependente da matéria orgânica e saturada com Al trocável, aumento do carbono orgânico em profundidade; (e) o Al é o principal cátion envolvido na podzolização, sendo que suas formas ativas são: complexos de Alhúmus e compostos inorgânicos pouco cristalinos. Os primeiros predominam nos horizontes superficiais e horizontes espódicos hidromórficos; as formas inorgânicas se relacionam a alguns horizontes espódicos (Bs, Bh, Bhs e Bsm) situados na base de perfis bem drenados; (f) Al inorgânico pouco cristalino também foi extraído pelos reagentes pirofosfato e CuCl2, geralmente utilizados para avaliar Al unido à matéria orgânica; ao contrário, LaCl3 extraiu apenas as formas ativas da interação Al-húmus, sendo que KCl não incluiu todas essas formas reativas; (g) a decomposição de raízes in situ e, sobretudo, os processos de formação e transporte de complexos Al-húmus foram observados em alguns (decomposição de raízes) ou em todos os perfis estudados (complexos Al-húmus), originando os horizontes espódicos às expensas dos eluviais; (h) a imobilização desses complexos se dá por diferentes mecanismos: filtragem físicomecânica dos poros do solo, aumento do pH em profundidade, incorporação adicional de Al durante seu transporte e o efeito da absorção seletiva das raízes. Neste último processo, as raízes absorvem seletivamente água e nutrientes, segregando e precipitando ao seu redor os complexos Al-húmus da solução do solo, mobilizados dos horizontes superiores ou presentes nas águas de drenagem. / The genesis, chemistry and macro and micromorphology of soils developed on the sandy coastal plain of the São Paulo State were investigated. In these environments, often designated restinga, podzolization is the main pedogenetic process, being Spodosols and Quartzipsamments the soils most commonly found. Cananéia, Ilha Comprida and Bertioga cities were selected for the development of this research due to the representativeness of this environmental condition in the São Paulo State. In these environments 31 soil profiles were described and sampled, mainly in chronosequences. Age of sediments and of organic matter of cemented horizons (ortstein) were investigated as well. These data associated to the chemical analysis, including Fe and Al selective dissolution procedures (dithionite-citrate, oxalate and pyrophosphate for Fe and Al; NaOH, KCl, LaCl3 and CuCl2 for Al) and micromorphological analysis allowed the following conclusions: (a) the most developed Spodosols have ortstein horizons and can be considered indicators of sediments of Pleistocene age from the Cananéia Formation of the studied quaternary coastal plain and possibly are paleosols; (b) time and relief were the main soil formation factors responsible for differentiation of Spodosols on the landscape; (c) the oldest and well drained soils due to relief conditions and sedimentary dynamics (Cananéia and Bertioga) showed great variability and diversity of their horizons and morphological properties, differing from the youngest, poorly drained and more homogeneous Spodosols usually without Bs horizon (Bertioga). The youngest and well drained Spodosols (Ilha Comprida) showed an advanced degree of degradation; (d) the chemical properties of the studied soils are similar to other soils already described in the restinga: low in exchangeable bases, low in base saturation, strongly acidic, organic-matter dependent and Al-saturated CEC, increase in organic carbon with depth; (e) Al is main metal related to the podzolization process. The reactive forms of this element are Al-humus complexes and inorganic poorly crystalline compounds. Alhumus complexes predominate in the superficial and spodic, poorly drained horizons; the Alinorganic forms occur in some well drained spodic horizons (Bs, Bh, Bhs and Bsm) situated at the bottom of the well-drained soil profiles; (f) Al inorganic, poorly crystalline forms were extracted by pyrophosphate and CuCl2 reagents, usually used to determinate Al bound to organic matter; unlike, LaCl3 only extracted the reactive forms of Al-humus interaction, whereas KCl did not include these reactive forms; (g) Al-humus formation and mobilization were the main pedogenetic processes, but roots decomposition were observed in some horizons; (h) different mechanisms are related to Al-humus complexes immobilization: physical-mechanical filtering effect on soil pores, precipitation as pH increases with depth, precipitation with the decrease of C-to-metal ratio during organic matter complexation and roots selective absorption effect. In the latter, there is selective absorption of water and nutrients with segregation and precipitation of Al-humus complexes around roots. These Al-humus complexes are either mobilized from the superficial horizons or already dissolved in the draining water.

Os solos são vitais para todos os ecossistemas terrestres e deles depende a maior parte dos recursos para a manutenção dos seres vivos. Seu uso é importante para a agricultura e, para assim serem usados, é necessário conhecê-los, tanto como são como onde estão na paisagem. Esse conhecimento pode ser adquirido através de levantamentos de solos para os quais existem muitas limitações, como alta demanda financeira, elevado tempo para sua execução e subjetividade associada ao conhecimento tácito dos pedólogos. Por isso, são necessárias novas estratégias que auxiliem a execução de mapas de solos. Uma abordagem promissora é a identificação de unidades naturais do relevo em nível de detalhe, uma vez que é possível predizer a ocorrência de atributos e tipos de solos na paisagem quando associando as feições dos seus perfis com as de sua superfície. Diante disto, este trabalho objetiva testar procedimentos digitais para segmentação detalhada de elementos das encostas e relacioná-los com os atributos e classes taxonômicas de solos. Em uma área de estudo de 2.500 ha, situada na região de Piracicaba (SP), parâmetros geomorfométricos organizados hierarquicamente em regras em uma árvore de decisão foram utilizados para classificar, em escala detalhada (1:10.000), os cinco elementos da encosta (topo, ombro, meia-encosta, sopé coluvial e sopé colúvio-aluvial). Avaliou-se uma estratégia de análise de similaridade visando à identificação de agrupamentos de amostras de solos da mesma classe, a partir de diferentes conjuntos de variáveis. Essa segmentação digital mostrou que é possível explicitar a localização de cada um dos elementos da encosta e que neles dominam perfis de solos que se assemelham. Na maioria dos casos, essa semelhança pode ser comprovada com o uso tanto de análises convencionais como espectrais das amostras de solo coletadas até 1 m de profundidade. Essa classificação digital dos elementos da encosta pode auxiliar no mapeamento de solos detalhados e ultradetalhados (escalas 20.000 ou maiores). / Soils are vital for all terrestrial ecosystems and the majority of resources for maintenance of human beings depend on them. Their use is important for agriculture and, in order to be used in this manner, it is essential to know them, as well as how they are and where they are located in the landscape. This knowledge can be acquired through soil surveys, that have several limitations, such as high financial demand, time-consuming execution and subjectivity associated with the pedologists tacit knowledge. Considering this, new strategies are needed to support the elaboration of soil maps. One promising approach is the identification of detailed natural units of relief, since it is possible to predict the occurrence of attributes and types of soils in the landscape when associating the features of their profiles with those of their surface. Therefore, this research aims to test digital procedures for detailed segmentation of hillslope elements and to relate them to soil attributes and taxonomic classes. In a study area of 2,500 ha located in the Piracicaba (SP) region, geomorphometric parameters hierarchically organized into rules in a decision tree were used in order to classify, in a detailed scale (1:10,000), five hillslope elements (summit, shoulder, backslope, footslope and toeslope). A similarity analysis strategy was used to identify groupings of soil samples from the same class, from different sets of variables. This digital segmentation showed that it is possible to make explicit the location of each one of the hillslope elements, where similar soil profiles are dominant. In most cases, this similarity can be verified with the use of both conventional and spectral analyses of soil samples collected up to a depth of 1 m. This digital classification of hillslope elements can support 1st and 2nd order soil survey (scales 1:36,680 or greater).

It is generally assumed that increased map precision (ie map unit homogeneity) and map purity (map unit accuracy) should result from increasing the scale of mapping of the soil resource, since it should enable a more intricate breakdown of the landscape into landform facet based units. This study compared the predictive success of a 1:10K scale soil association map with the 1:25K and 1:lOOK scale soil landscape maps within the Birrigai area of the Paddy's river catchment, south west of Canberra, A.C.T. The 1:25K and the 1:lOOK scale soil landscape maps were also evaluated in a second larger evaluation area in the Paddy's river catchment which allowed more of the larger soil landscape map units to be evaluated. The 1:25K scale soil map was produced by another author for the A.C.T Government, and was surveyed at a substantially lower survey intensity than that for the 1:lOOK and 1:10K scale soil maps (ie only 0.05 observation sites / cm2 of published map). These maps were evaluated using a set of randomly located independent evaluation sites in each evaluation area, and from these calculating and comparing standard Marsman & de Gruijter(1986) measures of Map Purity. The strength of soil-landscape relationships within this catchment were determined from a Fixed One Way Analysis of Variance, and from more simplistic graphical comparisons of the means and standard deviations of the discrete soil data within these landform based map units. Soil-landscape relationships for the Nominal scale soil data (ie class type data) were evaluated by comparing the Marsman & de Gruijter(1986) Homogeneity index ratings among the soil map units. Intensive survey traverses were also carried out in selected soil landscapes to further evaluate the strength of soil landscapes present. The results revealed obvious improvements in map quality associated with increasing map scale from 1:100,000 to 1:10,000, and these included increases in the predictive success (Map Purity), reductions in the extent of map unit impurities, and planning advantages associated with having individual land facets delineated on the 1:10,000 scale map. The respectable purity ratings achieved by the 1:100,000 scale soil landscape map (ie average purity rating of 63%) was largely attributed to the flexibility of the "soil material" approach to soil landscape mapping. The relatively poor performance of the 1:25K consultancy soil landscape map demonstrated the fact that; any benefit gained from the improved intricacy in the representation of map unit delineation's with increased mapping scale, will be drastically reduced if it is not matched by an associated increase in the intensity of field investigations. Evaluations of the soil-landscape relationships found that the land facets of the Paddy's river catchment generally failed to delineate areas that were both uniform and unique in respect of their soil properties. Soil-landscape relationships were instead found to be quite complex, applying to only certain land facets, and in regards to only certain soil properties. Soil maps with units based on landsurface features were recommended on the basis of the importance of other landscape factors other than soils to land capability ratings, as well as on the useability of such maps. This study recommended the adoption of a" >2 detailed soil profile observations / land facet in each map unit" mapping standard to ensure a reasonable estimate of the variability and modal soil conditions present, as well as a reliable confirmation of the perceived soil-landscape relationships. The error usually associated with small scale mapping was effectively reduced by rapid ground truthing, involving driving along the major roads dissecting the map area and making brief observations of soil exposures on road batters, despite the bias of the road network making such mapping improvements uneven across the map. The major point to come from this study was the re-emphasising of the point that soil spatial variability has to be accepted as a "real landscape attribute" which needs to be accurately described and communicated to land users, and must not be considered as some sort of soil mapping failure. The fact that individual facets of the landscape rarely coincide with unique pockets of uniform and unique soils and soil properties must be considered simply an on the ground reality of nature, and not some mapping failure. It was thought that since other landscape factors (eg hillslope gradient) most often dominate the determination of land use suitability and capability, it is better to effectively describe the range and modal state of the soil conditions within such facets, then to attempt to extrapolate possible soil boundaries using geostatistical techniques which cut across such land facets, and mayor may not correlate with real groupings of soil properties, depending on the spatial resolution of the soil variability distribution in the landscape. Even so the results of this investigation do put the validity of the physiographic terrain class mapping model as a predictor of soil traits under question, at least for the more complex landscape settings.

No description available.

A escassez de informações do solo que permitam o seu uso adequado, seja para fins agrícola, ambiental ou de projeto urbanos, pode ser minimizada com soluções provenientes do desenvolvimento de novas tecnologias. Nesse sentido, o presente estudo teve como objetivo aplicar duas estratégias digitais para obtenção de mapas de solos preliminares em áreas onde não foram realizados levantamentos pedológicos convencionais. As estratégias foram executadas com base em variáveis ambientais que estabelecem relações entre ocorrência de solos e suas posições na paisagem. A área de estudo compreendeu o município de Barra Bonita-SP, totalizando 11.072 ha. Para uso na predição dos solos pela técnica de Redes Neurais Artificiais (RNA) foram utilizadas as variáveis: declividade, elevação, perfil de curvatura, plano de curvatura e índice de convergência derivados de um Modelo Digital de Elevação (MDE), além das informações de geologia e das superfícies geomórficas identificadas na região. Na primeira estratégia, por meio de uma análise de agrupamento (Fuzzy k-médias) das variáveis, foram escolhidas cinco áreas chaves distribuídas na área de estudo, nas quais foi realizado levantamento de solos de nível semidetalhado para reconhecimento das unidades de mapeamento. Na estratégia 2, elaborou-se um mapa de solos de nível detalhado a partir de dados pré-existentes de apenas uma área chave, localizada no centro da região. Com a identificação das unidades de mapeamento foram gerados arquivos de treinamento e testes das redes neurais. Utilizou-se o simulador JavaNNS e o algoritmo de aprendizado backpropagation. Conjuntos de variáveis ambientais foram testados, avaliando a importância de cada variável na discriminação dos solos. A rede que exibiu melhor desempenho do índice Kappa foi utilizada para generalização de suas informações, obtendo os mapas digitais de solos. Pela aplicação de tabulação cruzada foram analisadas as correspondências espaciais entre os mapas digitais e um mapa convencional nível semidetalhado da região. Foram coletados pontos de referência para validar o desempenho dos mapas digitais. De acordo com a posição na paisagem e material de origem subjacente, notou-se tendência na ocorrência das classes de solos nas áreas chaves mapeadas. A mesma disposição dos solos foi observada nas classificações digitais. Os atributos do terreno elevação e declividade exibiram maior influência na distinção entre os solos pelas redes neurais em ambas as estratégias. A comparação com pontos de referência mostrou que o mapa digital produzido com base em unidades de mapeamento provenientes de abordagem convencional detalhada teve um desempenho superior (81,8% de concordância) ao mapa baseado em levantamento pedológico de nível semidetalhado (72,7%). Este estudo mostrou que a obtenção de mapas digitais de solos, com uso de variáveis ambientais que expressem a relação solo-paisagem, pode contribuir para a geração de informações preliminares do solo em locais não mapeados, a partir de unidades de mapeamento obtidas em áreas adjacentes. / The scarcity of land information to enable its proper use, whether for agricultural, environmental and urban design, can be minimized by solutions from the development of new technologies. Accordingly, this study aimed to apply two strategies to obtain digital maps of soil in areas where no preliminary surveys were carried out conventional pedological. The strategies were implemented based on environmental variables that establish relations between the occurrence of soils and their positions in the landscape. The study area comprised the municipality of Barra Bonita, SP, totaling 11,072 ha. For use in the prediction of soil by the technique of Artificial Neural Networks (ANN) were used variables: slope, elevation, profile curvature, plan curvature and convergence index derived from a Digital Elevation Model (DEM), in addition to information geology and geomorphic surfaces identified in the region. In the first strategy, through a cluster analysis (Fuzzy k-means) of variables, we selected five key areas distributed in the study area, soil survey being conducted semi-detailed level at these sites for recognition of the map units. In strategy 2, a map was drawn up detailed level of soil from pre-existing data of only one key area, located in the center of the region. Identifying the map units were generated files for training and testing of neural networks. Was used the simulator JavaNNS and learning algorithm \"backpropagation. Sets environmental variables were tested by assessing the importance of each variable to predict soil. The network showed better performance for the Kappa index was used to generalize their information, obtaining the digital soil maps. By applying cross tabulation analyzed the spatial correspondence between the digital maps and a conventional map of the region. Reference points were collected to validate the performance of digital maps. According to the position in the landscape and the underlying source material, was noticed a tendency of occurrence of soil classes in key areas mapped. The same arrangement was observed in the soil classifications digital. The attributes of the terrain elevation and slope exhibited a greater influence on the distinction between the soil by the neural networks in both strategies. The comparison with reference points showed that the digital map produced based on mapping units from the conventional approach detailed outperformed (81.8% agreement) to the map based on pedological survey of semi-detailed level (72.7 %). This study showed that to obtain digital maps of soils, use of environmental variables that express the soillandscape relationship, may contribute to the generation of information preeliminares soil in areas not mapped from map units obtained from adjacent areas.

O estudo teve por objetivo caracterizar e correlacionar os elementos do meio físico biótico, drenagem, geologia, formas de relevo, cobertura vegetal, solos e uso da terra, através da interpretação de fotografias aéreas, imagens de satélite e trabalhos de campo, bem como testar a técnica de amostragem circular de rede de drenagem para identificar unidades de mapeamento de solos no complexo Serra do Mar em São Paulo, que correspondem a áreas de difícil acesso, escarpadas, com densa rede de drenagem e densamente florestadas. A bacia do Guaratuba caracteriza-se por apresentar distintos compartimentos: a planície litorânea, onde ocorrem sedimentos marinhos e flúvio-marinhos sobre os quais se desenvolve uma vegetação pioneira herbácea e arbórea, com solos que apresentam em geral hidromorfismo (podzol e glei); o planalto, caracterizado por gnaisses com feições amorreadas, alternando solos podzólicos, cambissolos e litólicos sob floresta pluvial tropical; e, as serras e escarpas abruptas, revestidas por formações superficiais pouco espessas (litossolos e cambissolos) sobre granito, recobertas pelas florestas tropicais. Apresenta clima com precipitações acima de 2.000 mm por ano, sem estação seca definida e temperatura média anual de 19 a 25ºC. Como resultado foram produzidos os mapas da rede de drenagem, geologia, formas de relevo, declividade, hipsometria, vegetação e solos. Elaboraram-se também, 48 amostras circulares de 50 ha distribuídas pelos compartimentos do planalto, escarpa e planície litorânea na bacia do rio Guaratuba, trabalhando-se ainda, pontualmente em detalhe, com toposseqüências pedológicas. Concluiu-se com o estudo de amostras circulares, que o padrão de drenagem indica as formações geológicas predominantes, enquanto o número de rios e seus índices correlatos indicam os solos e o material superficial. A aplicação estatística aos índices de número, comprimento de rios, relevo, declive, geologia e vegetação mostrou-se mais eficiente na separação de grupamentos de solos nos subcompartimentos, agrupando amostras com mesmas associações de solos, facilitando o mapeamento. Conclui-se, ainda, que os elementos influenciam a distribuição e composição dos solos, devido à relação infiltração/deflúvio, que comanda o desenvolvimento e espessura dos mantos de alteração, modelando a topografia e, consequentemente, propiciando a instalação da vegetação. Para as zonas litorâneas, o relevo, a vegetação natural e o material geológico delimitam e definem unidades de solos distintas, podendo estes, serem mapeados por meio desses elementos. Assim, a vegetação exuberante e o clima local quente e úmido em toda a bacia, permitem dizer que na planície litorânea, as formas de relevo e a drenagem são os principais fatores no desenvolvimento dos solos, enquanto na escarpa e planalto, a declividade e o material de origem tornam-se mais decisivos. Observa-se portanto, uma relação direta entre os compartimentos morfológicos, a vegetação natural, a geologia e os solos nesta bacia hidrográfica, enquanto o detalhamento por toposseqüências, indica processos de transformação e evolução morfopedológicos, como as passagens de solos podzois para glei e de podzois para solos orgânicos, que fornecem indícios sobre a gênese e evolução da paisagem. O trabalho de mapeamento da zona litorânea, permite extrapolar os resultados para áreas contíguas, definindo as associações de solos, bem como a estrutura da cobertura vegetal natural e as formas de relevo presentes. Este fato deve ser observado em zonas que apresentem material geológico similar (granitos, gnaisses e respectivos sedimentos). / This study aims to characterize and correlate elements of the biotic-physical environment, drainage, geology, landform, vegetation cover, soil and land use by means of interpretation of aerial photographs, satellite images and field work. It also aims to test the technique of circular sampling the drainage network for identifying soil mapping units in the Serra do Mar complex, which corresponds to very steep areas, with dense drainage, and heavily forested areas, with difficult access. The Guaratuba watershed has distinctive compartments. In the coastal plain, pioneer herbaceous and arboreous plant species grow on redoximorphic soils developed on marine and fluvial-marine sediments (Spodosols and gley soils). The highlands have tropical rain forest on Ultisols, Inceptisols, and Entisols developed from gneissic bedrock in a hilly relief. The granitic escarpments have shallow soils (Entisols and Inceptisols) covered by tropical forests. The regional climate is characterized by an annual rainfall above 2000 mm, no distinct dry season, and an average temperature that can range locally from 19o to 25oC. Drainage, geology, landform, slope, hipsometry, vegetation and soil maps were produced. It was also produced in the Guaratuba watershed 48 circular samples, of 50 ha each, distributed in the highlands, mountains, and coastal plain. Additionally, pedological transects were studied in further detail locally. The circular sampling study concluded that the drainage pattern indicates the predominant geological formations, whereas the number of rivers and its associated indexes indicate the soils and the superficial material. The statistics of the number of river, river length, relief, geology, and vegetation indexes were more efficient in discriminating the soil groups in the sub-compartments, grouping samples with the same soil associations, easing therefore the mapping work. It was also concluded that the elements influence the soil distribution and composition, due to the infiltration/runoff ratio, which determines the development and thickness of the weathering mantle, shaping the relief and allowing the establishment of the vegetation. In the coastal areas, relief, natural vegetation and geological material determine distinctive soil units, which can be mapped through these elements. Thus, the exuberant vegetation and the hot and humid climate throughout the watershed support the idea that, in the coastal plain, the landforms and drainage are the main factors influencing soil development. Whereas in the highlands and in the mountainous areas, the slope and parent material give a more important contribution to soil development. It was observed in the whole watershed, therefore, a direct relationship between landform compartments, natural vegetation, geology and soils, whereas the localized study in the transects indicates transformation and morpho-pedological processes, like the ones where spodosols grade to gley soils, and spodosols grade to histosols, indicating landscape genesis and evolution. The work in the coastal zone allows the extrapolation of the results to contiguous areas, defining soil associations as well as the structure of the natural vegetation cover and landforms. This association should be expected in areas that have similar geology (granites and gneisses and its derived sediments).

Na Serra do Espinhaço Meridional, o predomínio de uma litologia quartzítica, associada a processos tectônicos diversos, proporcionou a formação de um complexo sistema de falhas, fraturas e dobramentos que, aparentemente, controlam a sedimentação quaternária e a rede de drenagem. Esta última, por sua vez, possui importante papel na formação de ambientes hidromórficos e na formação de turfeiras. Baseado na hipótese de que as turfeiras se formam em decorrência do controle exercido por estruturas quartzíticas sobre a rede de drenagem, gerando hidromorfismo, este trabalho objetiva estudar a relação entre morfoestratigrafia, hidrologia e os processos de formação das turfeiras a partir de uma análise espacial do meio físico, da configuração do embasamento rochoso, analisado pelo Radar de Penetração do solo (GPR), e de mudanças climáticas ocorridas no Pleistoceno e Holoceno. A análise do meio físico foi realizada a partir de uma compilação de cartas geológicas da área e do mapeamento das principais feições geomorfológicas, analisadas a partir de modelos gerados em sistemas de informação geográfica (SIG). A partir de uma análise detalhada dos produtos supracitados, foram selecionadas cinco microbacias hidrográficas com padrões geomorfológicos favoráveis a formação de turfeiras (planícies quartzíticas, vales suspensos, vales encaixados e vales alongados ladeado por vertentes suaves). Foram realizadas análises das geoformas e da drenagem por estereoscopia e transeções com o GPR. A cronologia dos eventos, bem como, a estratigrafia e a origem da MO foram analisadas por datações por C14, granulometria e fracionamento isotópico da MO, respectivamente. As turfeiras se formam, preferencialmente, em depressões formadas sobre litotipos mais susceptíveis ao intemperismo confinados entre quartzitos altamente resistentes onde a umidade tende a ser mantida. Dados do GPR mostram que as turfeiras ocorrem também associadas ao excesso de umidade mantido por soleiras quartzíticas em subsuperfície nos vales alongados adaptados a falhas e nos vales suspensos. Os soterramentos de turfeiras foram favorecidos por lineamentos tectônicos de direção E - W que controlam parcialmente a drenagem e a sedimentação na porção mediana da área. As variações nos processos sedimentares apresentam forte relação com mudanças climáticas ocorridas no Holoceno e Pleistoceno. Pelo menos seis períodos de mudanças climáticas foram observadas: entre 30.251 a 12.418 anos AP o clima favoreceu a deposição de MO; de 12.418 a 7.890 anos AP os processos erosivos foram mais intensos; de 7.890 a 3.280 anos AP o clima quente e úmido favoreceu o deposito de MO e, nos últimos 2.590 anos AP, o clima foi semelhante ao atual com 3 períodos breves favoráveis a deposição de turfa observado por camadas discretas de MO. / The morphology of the Serra do Espinhaço Meridonal is associated with various tectonic processes. In combination with the prevalence of a quartzite lithology this caused the formation of a complex system of faults, fractures and folds that control the Quaternary sedimentation and drainage network. Impeded drainage cause hydromorphic environments in which organic matter (OM) may accumulate, causing the formation of peatlands. Based on the hypothesis that the formation of peatlands in this area is controlled by impeded drainage of quartzite structures, the aims of this thesis were (i) to study the relationship between morphology, stratigraphy and hydrology, (ii) to determine the influence of this relationship on the formation of peatlands, and (iii) to interpret this in the context of climatic changes in the Pleistocene and Holocene. This will be done by a spatial analysis of the physical environment of five watersheds. The watersheds were selected based on geomorphological patterns that favor peat formation, including quartzite plains, hanging valleys and elongated valleys flanked by gentle slopes. The configuration of the rocky basement will be determined with Ground Penetrating Radar (GPR), a compilation of geological maps of the area will be made, and the main geomorphological features will be examined using Geographic Information Systems (GIS) models. The chronology, stratigraphy and origin of OM were analyzed by C14 dating, particle size and isotopic fractionation, respectively. The results indicate that the peatlands are preferentially formed on rock types other than quartzite, which are occasionally located between the highly resistant quartzite rocks. Because this material is more susceptible to weathering, depressions were formed in which water tends to accumulate, thereby providing conditions that favor peat formation. However, GPR data showed that peatlands were also formed on quartzite rocks when the subsurface showed elongated valleys adapted to crashes and hanging valleys. Burried peat was found at some places, which was related to tectonic lineament patterns with an east-west direction. These tectonic lineament patterns partially controlled the drainage and sedimentation in the central part of the area. Variation in sedimentary processes (peat formation vs. mineral influx/erosion) was found to be strongly related to climatic changes in the Holocene and Pleistocene. At least six periods of climate change were observed: between 30.251 and 12.418 yr BP climate favored the deposition of OM, between 12,418 and 7890 yr BP erosion processes were more intense; between 7.890 - 3.280 yr BP a hot and humid climate favored peat formation, and the last 2.590 years the climate was similar to the current favorable with three brief periods of peat deposition were observed.