Rural households in the West African Sahel have developed livelihood systems that allow them to survive in one of the most challenging social-ecological systems on Earth. These households have experienced environmental shocks including droughts, floods, and extreme heat for hundreds of years, and have well-established coping and adaptation mechanisms that allow them to recover from all but the most severe shocks. Climate change, particularly increased climatic variability, may stress Sahelian livelihood systems to the point that households must deploy a new set of coping and adaptation strategies in order to survive. This research, conducted as three interrelated mixed-method studies, explores the coping and adaptation strategies used by Tuareg transhumant pastoralists in Niger starting with the deep drought of 1968-1974.The first study involves rural households in the Tahoua Region of central Niger. These households have adapted to climate change and other livelihood stressors primarily by diversifying their assets, utilizing new technologies, and reducing the length of their annual transhumance. While there are donor-funded programs designed to assist rural households with adaptation to climate change, the households in this study have not been the beneficiaries of such programs. The second study attempts to disentangle climate shocks from other factors driving rural-urban migration while also exploring which households migrate to urban areas, and why. Climate change is perceived as the main factor driving rural-urban migration, as well as other livelihood changes. Household-level preferences, management skills, and luck played a greater role that asset endowments in determining which households would migrate to urban areas. The third study focused on livelihood strategies of households that had migrated to, and settled in, urban areas. These households worked hard to maintain social capital with their rural kin while also building social capital in their new urban environment. Social capital with expatriates and urban elites was an important element of urban households' asset endowment. Urbanized households possess significantly fewer livestock than their rural counterparts, and struggle to manage the cash earned from relatively low-paying wage labor. These three studies demonstrate that pastoralists perceive climate change as a significant driver of changes in livelihood strategies. Pastoralists' perceptions of climate change broadly match climate data. Furthermore, pastoralists, with little to no assistance from the state or development organizations, are successfully adapting to climate change in ways that are likely to increase their resilience to future climate shocks.

The grain amaranths, Amaranthus cruentus and Amaranthus hypochondriacus have been promoted as grain-bearing plants of possible high productivity in saline or hot arid habitats. To investigate these claims, seeds of both species were germinated at 10, 15, 20, 25, 30, 35 and 40°centigrade. Germination percentage for both species was above 90% after four days at 20, 25, 30, and 35°C. Germination was negligible at 10 and 15°C and very low at 40°C. Seeds were germinated in isotonic solutions of PEG and NaCl at 0.0, -0.2, -0.4, -0.5, -0.6, -0.8, and -1.0 MPa osmotic potential at 30°C. Germination percentage was high in the range 0.0 to -0.4 MPa and dropped rapidly to zero in the -0.6 to -1.0 MPa range. Differences due to chemical effects were significant. Species differences were not. Radicles and hypocotyls were measured after six days in the above media. PEG was more inhibitory of seedling growth than was NaCl and generally inhibited A. cruentus more than A. hypochondriacus. This was also true of NaCl. All growth functions were slightly inhibited at 0.0 to -0.4 MPa and very inhibited above -0.6 MPa. PEG radically increased root/shoot ratio in both species.

Differential adaptations of barley (Hordeum vulgare L.) and wheat (Triticum spp.) genotypes suggest that they be evaluated under multi-environmental conditions. The objectives of this study were to determine if small grain genotypes, bred for various moisture conditions, respond differently in terms of yield, water use, and rooting pattern to contrasting moisture conditions. Eight small grain genotypes were compared under a gradient of water from 89 to 404 mm (plus 254 mm of stored water) in a field study at Marana, AZ. A barley bred for low input conditions had greater root density in the subsoil and used moisture earlier in the season when compared to a high input barley (WestBred Gustoe). The cultivars bred for high input conditions required more water for optimum yield compared to those bred for low input conditions.

Those epiphytes which are inhabited by ants are reviewed; they comprise nine genera in four families. All are tropical and most are from the Far East. They probably all gain mineral nutrients from material brought by the ants. This contrasts with myrmecophytic trees and shrubs which are defended against insect herbivores by ants collecting food produced by the plant. five of the nine genera of ant-epiphytes belong to the Rubiaceae; two of these, Hydnophytum and Myrmecodia are highly diversified and specialized. They are found throughout the tropical Far East in a range of habitats, but are most abundant in open canopies. Ants (Iridomymex cordatus and I. cf. scrutator) occupy cavities in the enlarged hypocotyl. The 'tuber' cavities and other unusual morphological features are elaborated in Myrmecodia. For instance, spines of different types are derived from adventitious roots; internodes are condensed and covered by outgrowths at each leaf-base; stipules are enlarged and differ in their splitting. The inflorescence rachis is progressively reduced in Hydnophytum, and the flowers sunk in the stem in Myrmecodia. These structural changes possibly benefit the ants, but may have reduced the frequency of crosspollination, though some heterostyly is present. The morphology of the satellite genera (Myrrnephytum, Anthorhiza and Squamellaria) shows some parallels with that of Myrmecodia. The five genera are united as a subtribe - the Hydnophytinae. Detailed taxonomic treatment of Myrmecodia and the satellite genera, but not Hydnophytum, is given. Myrmecodia is reduced from 43 to 18 species. One is a variable, widespread, lowland species which is divided into informal categories. One is polytypic with three subspecies, four are variable, but not divided, and the rest are monotypic, geographically restricted, mostly montane species. The pattern of variation is often reticulate, and a hierarchy or infrageneric grouping was not identified. Myrmecodia and the satellite genera appear to have evolved independently from Hydnophytum-like ancestors. Structures probably advantageous to the ants have arisen repeatedly, but may also have led to inbreeding and taxonomic difficulty. The more sophisticated symbiosis in Myrmecodia may be reflected by the more mesomorphic nature of that genus, and is a prime example of coevolution between higher plants and animals.

Electrical Resistivity Tomography (ERT) is a novel technique which can be used to build up a 2D pseudo-section of resistivity distribution of a porous material. Here, it is used to visualise internal moisture regimes by measuring the resistivity distribution of transects within sandstone, inferring that high resistivity equals low moisture content and vice versa. This method was used to perform two intermediate complexity laboratory tests; the first one to determine high-resolution, multi-scale drying patterns of sandstone, the second to determine capillary ingress of moisture within a sandstone block and the influence of temperature on moisture distribution. It was found that moisture behaviour showed far more complex patterns than previously acknowledged. A new model is therefore proposed which describes the influence of increased near-surface temperatures on capillary rise. This series of tests bridge the gap between field observations and mathematical models, as well as confirm the validity of ERT as a geomorphological tool. This research was continued by investigating the role of internal moisture in sandstone weathering using the Golden Gate Highlands National Park (GGHNP), South Africa as a case study. The ERT data was correlated with Equotip (rock surface hardness) and Protimeter (rock surface saturation) measurements. Seven sites were investigated, which showed that there is a non-linear correlation between rock surface hardness and internal moisture patterns. In addition, annual change measurements confirmed that the fluctuating patterns of internal moisture can be correlated to strengthening or weakening of the rock surface. This research therefore proposes two new conceptual weathering models. The first correlates ‘optimal moisture content’ to rock surface strength. The second correlates the development of shelters and changing weathering patterns to the non-linear interaction between case hardening and internal moisture. This new approach to sandstone weathering can be incorporated into conservation methods, as rock surface loss is one of the main causes of the San Rock Art deterioration observed in the GGHNP.

The oases of the northern Sahara illustrate the possibility that people and nature can work together to enhance life in a harsh and variable environment. This research investigates fifty years of experiences of living with environmental change in oasis systems, bringing together new data, archived environmental records and cultivators` observations. These are combined to gain insight into the environmental change processes, and the experiences gained by people through living with them in this regional context. Two detailed case studies deepen understanding of the socioeconomic dimensions and significance of these changes over the past two decades. The findings show how environmental changes constrained smallholders` traditional ecosystem management practices. Collective associations were weakened or disintegrated. National systems for environmental management and monitoring were overwhelmed. International recommendations for economic approaches to resource management and innovation to address water scarcity did not prove effective. On the other hand, instances where the international market transition appeared to be creating new opportunities for the restoration of common pool resource management were also identified. This investigation enabled a new perspective on the global dryland management debate to be generated in a context where research has most commonly been concentrated on national sectoral objectives for productivity and desert reclamation. Theoretical insights regarding the application of interdisciplinary research to understand environmental change, further research needs, and potential solutions are directly transferable to other regions where desiccation, salinization and groundwater degradation are accelerating due to climatic and global market-driven changes in land and water use.

Climate change has varying effects across the world. In North America, arid and semi-arid regions are subject to creeping warming together with more extreme climate variations, decreasing precipitation, and decreasing river flows that risk livelihoods of human populations living in these areas, and push their capacity to adapt beyond known boundaries. Environmental impacts act together with effects of socio-economic globalization and challenges imposed by institutional and policy events. These multiple forms of globally-driven changes interact with local communities and produce winners and losers depending on their levels of vulnerability and adaptive capacity, as well as on the specific stressors and shocks affecting the livelihood resources on which they depend. Rural communities often are hot spots of global change impacts because many livelihoods depend on the community’s natural resource base, and in several cases, they are also subject to market fluctuations and crashes due to their participation in international chains of food and producer goods. They will face a larger burden of the global change impacts due to this multi-tiered exposure. The socio-economic and institutional changes affecting rural communities have also produced de-agrarianization of livelihoods. Diversified livelihoods based on extractive industries and manufacturing or urban-based jobs coexist with traditional small-scale ranching and farming. In terms of water and land access and use, the modifications in user sectors and necessities, combined with increased demand by social and ecological components of the watershed systems, creates more complexity of environmental governance regimes and institutions. The purpose of this research is to identify and understand how rural communities of arid Northwest Mexico—with reference to the San Miguel Watershed (SMW) in central Sonora State—experience and respond to globally driven environmental, socio-economic, and institutional changes. The SMW is in a rapidly changing arid transboundary region, and exhibits a variety of institutional arrangements for land and water management, which makes it a case suitable for the study of adaptation in the face of global change. The study employs a combination of quantitative and qualitative methodologies in three municipalities representing the upper, middle, and lower SWM. Rural households and producers, governmental agents, and local leaders were the participants of direct data collection, while documentary analysis and a broader literature review on rural adaptation in Mexico and the arid Southwest United States complemented primary data. The main contributions of the research are: 1) identifying multiple types of rural livelihoods and their importance in understanding adaptation to global change; 2) emphasizing institutional events and factors acting as both stressors and regulators in these adaptation processes, 3) describing how interactions between institutions can produce diverse governance outcomes in terms of access and management of resources for livelihoods' adaptation; and 4) providing empirical evidence for improving adaptation policies in rural arid Northwest Mexico, and other rural arid communities of the world. The study also includes a series of findings and lessons regarding advances in understanding human adaptation in rural communities, contributions to the theory and methods of adaptation science, and policy guidelines based on the findings.

The electricity sector around the world is significantly changing towards the adoption of cleaner energy sources and its implementation through distributed generation technologies. The need to expand rural electrification to reduce energy poverty and the trends in decentralizing power generation are becoming major drivers of change. In Mexico, there are very few comprehensive studies on energy use and its impact on rural livelihoods. Energy studies in the development literature tend to analyze livelihoods that do not have access to modern energy services, and do not take into account that many rural communities, although connected to the grid, still may be considered energy poor. This research presents findings of current livelihood conditions of three rural communities in the Mexican state of Chihuahua, in the context of livelihood diversification and energy poverty. This paper also presents a feasibility study for the development of a community energy model that will fulfill energy and vegetable intake requirements for each community analyzed. Results show that these communities can potentially improve their livelihood conditions through the implementation of what this research calls a Community Integrated Sustainable Energy (CISE) model by reducing energy poverty and food insecurity. By adopting a CISE model, communities will become healthier by becoming supporters of energy conservation and energy efficiency strategies. The adoption of this community energy model will also encourage climate change mitigation by increasing resilience to vulnerable communities through enhancing food and energy security. The aim of this research is to inform stakeholders (including policy makers, urban planners, and community members themselves) of the current status of Chihuahua's communities and to start a dialogue in Mexico about engaging in a community-led, clean energy project that would generate electricity for those communities while preserving rural livelihoods.

A caatinga foi reconhecida recentemente como uma das 37 grandes regiões naturais do planeta. De um modo geral, tem sido descrita na literatura como pobre, possuindo baixo valor para fins de conservação. Talvez devido a este fato, a caatinga seja o bioma brasileiro mais desvalorizado e menos conhecido botanicamente, permanecendo como um dos mais desconhecidos na América do Sul do ponto de vista científico. Neste contexto, é preemente a necessidade da ampliação do conhecimento sobre a distribuição de organismos e a forma como eles estão organizados em comunidades na caatinga. No Estado do Ceará, a caatinga é a unidade fito-ecológica mais representativa espacialmente, abrangendo aproximadamente 72.980 Km2 e apesar da grande abrangência espacial da caatinga, pouco se conhece ainda sobre seus padrões de comunidades vegetais no Estado. Assim, este trabalho objetivou contribuir com a ampliação do conhecimento sobre a caatinga, investigando a flora e estrutura, bem como realizando o mapeamento orbital das fisionomias existentes na vegetação da Estação Ecológica (EE) de Aiuaba, Ceará. Esta é uma área considerada, pelo Programa Nacional da Biodiversidade/PROBIO, de Alta Importância Biológica no estado do Ceará. Foram realizadas coletas botânicas mensais, aleatórias, no período de outubro/2003 a fevereiro/2005, de ervas, subarbustos, arbustos, árvores, epífitas e lianas. A coleção botânica encontra-se depositada no acervo dos Herbários SPF, EAC, HUVA, IPA e K. No levantamento florístico foram coletados 183 espécimes, pertencentes a 47 famílias, 113 gêneros e 161 espécies. Deste total, dois táxons estão sendo propostos como espécies novas para a ciência. As famílias mais ricas em termos específicos foram Leguminosae, Euphorbiaceae, Bignoniaceae, Convolvulaceae, Acanthaceae e Asteraceae, as quais responderam por 51,5% do total das espécies. O maior índice de similaridade de Sørensen (IS) verificado entre a área de estudo e outros levantamentos realizados em diferentes estados do Nordeste brasileiro foi de 23,33%. Algumas espécies registradas na EE apresentam distribuição em todo o semi-árido nordestino, com algumas ocorrendo em outros estados brasileiros e até em outros países da América do Sul. Para o estudo fitossociológico, foram alocadas através de sorteio, 50 parcelas de 10 x 10 m em uma área de 1,5 ha. Foram medidos os caules de todos os indivíduos lenhosos vivos ou mortos ainda em \"pé\", inclusive cipós, que se individualizassem ao nível do solo e que atendessem aos seguintes critérios: Diâmetro ao Nível do Solo (DNS) >= 3 cm e altura total (AT) >= 1 m. Foram amostrados 3.007 indivíduos distribuídos em 47 espécies e 21 famílias. Leguminosae, Euphorbiaceae, Erythroxylaceae, Acanthaceae, Bignoniaceae e Rutaceae responderam por 65,9% das espécies e as três primeiras totalizaram 62,97% do valor de importância total. Croton floribundus (Euphorbiaceae), Piptadenia moniliformis (Leg. Mimosoideae), Erythroxylum caatingae (Erythroxylaceae) e Bauhinia cheilantha (Leg. Caesalpinioideae) tiveram os maiores valores de importância. As alturas e os diâmetros médios e máximos foram 4,51 e 13 m e 7,28 e 44,88 cm, constatando-se tratar de um trecho de caatinga cuja maioria dos indivíduos concentra-se no estrato inferior a 5 m de altura, com algumas espécies emergentes. O uso de imagens CBERS-2 e dados de campo proporcionaram a elaboração de um mapa da vegetação da EE de Aiuaba. Através de processamento de imagens, utilizando o Normal Difference Vegetation Índex (NDVI), foi produzido um mapa vegetacional. Foram diagnosticadas três fisionomias vegetacionais, havendo predomínio de caatinga arbustiva-arbórea alta aberta. A importância deste estudo está nas informações básicas acerca do estado atual da vegetação, vindo a fornecer subsídio para estudos futuros relacionados à compreensão e previsão de mudanças no padrão de distribuição das comunidades vegetais, bem como possibilitar a efetivação de investigações mais detalhadas. No aspecto geral, este estudo gerou informações acerca da diversidade biológica e ambiental da EE de Aiuaba. Informações como estas são fundamentais para o entendimento da evolução, da ecologia e da conservação de uma biota, vindo a fornecer suporte às decisões governamentais nas áreas de proteção ambiental, bem como no manejo das mesmas / Caatinga was recently recognized as one of the 37 great natural regions of the planet. In general, it has been described in literature as poor, having little value for conservation purposes. Perhaps due to this fact, caatinga may be the most devalued and least botanically recognized Brazilian biome, remaining as one of the most unknown in South America from a scientific point of view. In this context, the need for broadening knowledge about the distribution of organisms and the way they are organized into communities in caatinga is predominant. In the state of Ceará, caatinga is the most spatially representative phyto-ecological unit, covering approximately 72,980 Km2 and despite the great spatial coverage of caatinga, little is yet known about its patterns of vegetal communities in the State. Therefore, this study aims to contribute to the broadening of knowledge about caatinga, investigating the flora and structure, as well as carrying out the orbital mapping of the existing physiognomies in the vegetation of the Estação Ecológica (EE) in Aiuaba, Ceará state. This is an area considered, by the National Biodiversity Program/PROBIO, to be of High Biological Importance in the state of Ceará. Random monthly botanical collections were carried out, in the period from October/2003 to February/2005, of herbs, subshrubs, shrubs, trees, epiphytes and lianas. The botanic collection is to be found deposited in the SPF, EAC, HUVA, IPA and K Herbarium collections. In the floristic survey 183 specimens were collected, belonging to 47 families, 113 genera and 161 species. From this total, two taxa are being proposed as new species for science. The richest families in specific terms were Leguminosae, Euphorbiaceae, Bignoniaceae, Convolvulaceae, Acanthaceae and Asteraceae, which corresponded to 51.5% of the species total. The highest Sørensen\'s Similarity Index (IS) rate verified between the study area and other surveys carried out in different states of the Brazilian Northeast was 23.33%. Some species registered in the EE present a distribution throughout the northeastern semi-arid area, with some occurring in other Brazilian states and even in other South American countries. For the phyto-sociological study, 50 plots of 10 x 10m in an area of 1.5ha were assigned, by means of a draw. The stems of all living or dead but still \"standing\" woody organisms were measured, including lianas, which might become distinct at ground level and which might observe the following criteria: Diameter at Ground Level (DNS) >= 3cm and Total Height (AT) >= 1m. Three thousand and seven organisms were sampled distributed into 47 species and 21 families. Leguminosae, Euphorbiaceae, Erythroxylaceae, Acanthaceae, Bignoniaceae and Rutaceae corresponded to 65.9% of the species and the first three totaled 62.97% of the total importance value. Croton floribundus (Euphorbiaceae), Piptadenia moniliformis (Leg. Mimosoideae), Erythroxylum caatingae (Erythroxylaceae) and Bauhinia cheilantha (Leg. Caesalpinioideae) had the greatest importance values. The average and maximum heights and diameters were 4.51 and 13m and 7.28 and 44.88cm, proving that deals with a stretch of caatinga where the majority of organisms are concentrated in the stratum of less than 5m in height, with some emergent species. The use of CBERS-2 images and field data provided the elaboration of a vegetation map at the EE in Aiuaba. Through the processing of images, using the Normal Difference Vegetation Index (NDVI), a vegetation map was produced. Three vegetational physiognomies were diagnosed, with a predominance of tall open shrubby-arboreal scrub. The importance of this study is in the basic information regarding the current state of vegetation, providing assistance for future studies related to the understanding and forecast of changes in the distribution pattern of vegetal communities, as well as enabling the effectuation of more detailed investigations. In a general aspect, this study generated information about the biological and environmental diversity of the EE in Aiuaba. Information like this is fundamental for the understanding of evolution, ecology and the conservation of a biota, providing support for governmental decisions in areas of environmental protection, as well as in the management of them

Este trabalho faz parte do processo de investigação e conhecimento da evolução da paisagem a partir da interação solo-relevo, isto é, de uma abordagem pedogeomorfológica. Como tais estudos são escassos no semiárido brasileiro e, considerando o interesse em contribuir com o conhecimento e disseminação da geo e biodiversidade deste domínio, foi selecionada para estudo uma área localizada no setor nordeste do estado da Bahia, próxima ao município de Nova Soure. O recorte espacial adotado foi a bacia de drenagem, por entender que a bacia é, mesmo em condições semiáridas, uma unidade importante para a compreensão das relações entre formas e materiais, como a cobertura pedológica. A bacia selecionada é a do Riacho Natuba, que está, geologicamente, localizada na bacia sedimentar do Tucano Sul, que integra o rifte Recôncavo-Tucano-Jatobá. Geomorfologicamente está inserida nos Tabuleiros do Itapicuru, formados por modelados de aplainamentos e dissecação. O estudo foi realizado a partir de etapas de gabinete, campo e laboratório, que incluíram: revisão bibliográfica e conceitual, levantamento de materiais cartográficos, processamento de imagens e produção de mapas através do geoprocessamento, trabalhos de campo com reconhecimento da área, descrição e coleta de perfis de solos, análises laboratoriais e estudos microscópicos de seções delgadas. Diferentes escalas foram adotadas para o estudo da relação solo-relevo. Na escala da bacia, o estudo foi realizado a partir da identificação e descrição dos compartimentos morfopedológicos. Na escala da vertente, o estudo foi realizado a partir da descrição e caracterização de solos ao longo de transectos entre os compartimentos morfopedológicos e na escala de detalhe foram observadas as microestruturas em lâminas com o auxílio de microscópios petrográficos. Os resultados indicaram que a bacia é pedodiversa e que essa variedade e distribuição de solos possui íntima relação com a variação de litofácies da Formação Marizal e com processos do relevo, como a erosão seletiva superficial e subsuperficial de finos (argilas). Os solos de maior ocorrência nas partes altas da bacia são os Neossolos Quartzarênicos, que se diferenciam pelo conteúdo de argila, composição mineralógica e arranjos do fundo matricial. Essas distinções foram interpretadas como produtos da influência da circulação da água, atestando a importância do relevo na sua gênese. Nas partes baixas da bacia, a diversidade de solos é maior, ocorrendo Argissolos, Luvissolos, Chernossolos, Neossolos Fluvicos e Planossolos. Todos refletem propriedades dos materiais de origem sob condições de intemperismo típicas do semiárido, como a fertilidade, a mineralogia e as organizações micromorfológicas. Além disso, também estão relacionados aos processos erosivos atuantes nas vertentes, que formam, por exemplo, o gradiente textural, seja através da elutriação (Argissolos e Luvissolos) ou através da sedimentação (Planossolos). De maneira geral, os solos da bacia estão interligados entre si, e essa ligação se dá a partir da redistribuição de material ao longo das dinâmicas do relevo. Este contexto expressa a importância de considerar conjuntamente a pedogênese e morfogênese na evolução da paisagem semiárida. / This work is part of the process of research and knowledge of the evolution of the landscape from the interaction between soil and relief, i.e., a soil geomorphological approach. Aiming to contribute to and disseminate the knowledge of the geo- and biodiversity of the Brazilian semiarid, where studies such as this one is rare, we investigated an area in the northeast of Bahia, near the Nova Soure municipality. The drainage basin was picked as the unit of spatial analysis because, even in semiarid conditions, we understand it to provide the best comprehension of the relationships between shapes and materials, such as soil coverage. The Natuba stream drainage basin we investigate in this study is geologically situated in the Tucano Sul sedimentary basin, itself part of the Recôncavo-Tucano-Jatobá rift. Geomorphologically, the basin is part of the Itapicuro tablelands, formed by surfaces of planation and dissection. The investigation involved office, field, and laboratory stages, including: literature and conceptual review, gathering of cartographic material, image processing, geoprocessing to produce maps, area survey and fieldwork, profile description and sampling, laboratory analysis, and thin section microscopy. We adopted different scales to study the soil-relief relationship. At the basin-scale, the study comprised the identification and description of morphopedological compartments. At the slope-scale, the study was derived from the description and characterization of soils along transects between morphopedological compartments. Finally, at the detail-scale we observed the microstructures on slides, using petrographic microscopes. Results indicate that the basin is soil-diverse and that its variety and distribution is intimately related to the variation of the lithofacies of the Marizal Formation and to relief processes such as superficial and subsuperficial erosion of fine material (clays). The Quartzarenic Neosols, more frequent in the higher regions of the basin, are differentiated by the clay content, mineral composition, and the relative distribution of groundmass. These distinctions were interpreted as products of the influence of water circulation, substantiating the importance of the relief in the soil genesis. At the lower regions of the basin, the soil is more diverse: Acrisols, Luvisols, Chernozems, Fluvisols, and Planosols occur. Fertility, mineralogy and micromorphological organization of the soils are typical of the original material enduring conditions of weathering that are characteristic of the semiarid. Furthermore, the soils are related to the erosive processes that affect the slopes and form, for instance, the textural gradient as a result of elutriation (Acrisols and Luvisols) or sedimentation (Planosols). Generally, the basin soils are interlinked via the redistribution of material throughout the landscape. This context, therefore, expresses the importance of considering both pedogenesis and morphogenesis when examining the evolution of the semiarid landscape.