Hydrogeomechanics for rock engineering: coupling subsurface hydrogeomechanical assessement and hydrogeotechnical mapping on fracturated rock masses

The present work aims to achieve and further develop a hydrogeomechanical approach in Caldas da Cavaca hydromineral system rock mass (Aguiar da Beira, NW Portugal), and contribute to a better understanding of the hydrogeological conceptual site model. A collection of several data, namely geology, hydrogeology, rock and soil geotechnics, borehole hydraulics and hydrogeomechanics, was retrieved from three rock slopes (Lagoa, Amores and Cancela). To accomplish a comprehensive analysis and rock engineering conceptualisation of the site, a multi‐technical approach were used, such as, field and laboratory techniques, hydrogeotechnical mapping, hydrogeomechanical zoning and hydrogeomechanical scheme classifications and indexes. In addition, a hydrogeomechanical data analysis and assessment, such as Hydro‐Potential (HP)‐Value technique, JW Joint Water Reduction index, Hydraulic Classification (HC) System were applied on rock slopes. The hydrogeomechanical zone HGMZ 1 of Lagoa slope achieved higher hydraulic conductivities with poorer rock mass quality results, followed by the hydrogeomechanical zone HGMZ 2 of Lagoa slope, with poor to fair rock mass quality and lower hydraulic parameters. In addition, Amores slope had a fair to good rock mass quality and the lowest hydraulic conductivity. The hydrogeomechanical zone HGMZ 3 of Lagoa slope, and the hydrogeomechanical zones HGMZ 1 and HGMZ 2 of Cancela slope had a fair to poor rock mass quality but were completely dry. Geographical Information Systems (GIS) mapping technologies was used in overall hydrogeological and hydrogeomechanical data integration in order to improve the hydrogeological conceptual site model.

Delineating environmental groundwater vulnerability and protection zones mapping in fractured rock masses

Hard‐rock watersheds commonly exhibit complex geological bedrock and morphological features. Hydromineral resources have relevant economic value for the thermal spas industry. The present study aims to develop a groundwater vulnerability approach in Caldas da Cavaca hydromineral system (Aguiar da Beira, Central Portugal) which has a thermal tradition that dates back to the late 19th century, and contribute to a better understanding of the hydrogeological conceptual site model. In this work different layers were overlaid, generating several thematic maps to arrive at an integrated framework of several key‐sectors in Caldas da Cavaca site. Thus, to accomplish a comprehensive analysis and conceptualization of the site, a multi‐technical approach was used, such as, field and laboratory techniques, where several data was collected, like geotectonics, hydrology and hydrogeology, hydrogeomorphology, hydrogeophysical and hydrogeomechanical zoning aiming the application of the so‐called DISCO method. All these techniques were successfully performed and a groundwater vulnerability to contamination assessment, based on GOD‐S, DRASTIC‐Fm, SINTACS, SI and DISCO indexes methodology, was delineated. Geographical Information Systems (GIS) technology was on the basis to organise and integrate the geodatabases and to produce all the thematic maps. This multi‐technical approach highlights the importance of groundwater vulnerability to contamination mapping as a tool to support hydrogeological conceptualisation, contributing to better decision‐making of water resources management and sustainability.

Spatial and temporal analysis of recent drought using vegetation temperature condition index: case of Somali regional state of Ethiopia

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

Spatial-temporal analyses of climate elements, vegetation characteristics and sea surface temperature anomaly. A Case study in Gojam, Ethiopia

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

Recent droughts and the impact of North Atlantic Oscillation in Iberia; a spatiotemporal analysis based on vegetation temperature condition Index (VTCI)

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

Vegetation near Santa Teresinha, NE Mato Grosso.

The Santa Tenesinha region in northeaster Mato Grosso has a varied vegetation which is principally hammock pantanal. The flat clayey alluvial ground between the hummocks is coveted with a continuous non-cerrado ground cover dominated by grasses but which harbors sedges and a lange herb flora. No woody plants grow in it. The tops of the 10-20m wide, slightly elliptical hummocks, 1.5-2 m high, 10-40 per hectare, are covered with cerrado plants: herbs, semlshrubs, thin- and thick-stemmed shrubs and low trees. For 4-5 months during the latter part of the rainy season, the regional water table rises to the surface and the ground between the hummocks becomes saturated or floods up to 1.5-2 m deep. The tops of the hummocks almost always remain above high water level. In the dry season the surface soil dries out completely. This alternation of saturation or shallow flooding and dryness, prevents woody plant, growth between the hummocks, and except for a few tolerant species, also prevents woody plant. growth on the lower part of the hummochs. The gallery forests in the pantanal are seasonally flooded more deeply but their soil does not dry out so thonoughly in the dry season so woody plant growth is not prevented.

Preliminary notes on the macrolichens of Serra do Cachimbo, northcentral Brazil

This paper reports on the April-May 1983 Projeto Flora expedition to Serra do cachimbo in northcentral Brazil, a phytogeographically poorly known area near the transition between the Amazon forest and the central Brazilian planalto. The objective of this expedition was to collect botanical specimens with special emphasis on lichens. Rock outcrops are common in this area and several soil types combined with varied topography give rise to a diversity of vegetation types including Amazon caatinga, campo rupestre, gallery forest and Amazon forest. A preliminary checklist of 91 macrolichens is provided with a discussion of ecological distribution of lichens in each habitat.

TRANSFERTS DE QUANTITE DE MOUVEMENT AU-DESSUS ET A L'INTERIEUR DE LA VEGETATION

The aborptlon of momentum by the vegetation Is studied In this work through an analytical approach which also provides the appropriate formulations to describe wind velocity and drffusivities profiles above and Inside the space occupied by the foliage elements. A first comparison between the observed and calculated profiles of wind volocity for Amazonian forest (Réserva Pucke, Manaus - AM) is presented to test the realism of the model.

THE VEGETATION OF A SEASONAL VÁRZEA FOREST IN THE LOWER SOLIMÕES RIVER, BRAZILIAN AMAZONIA

The species composition of the seasonal várzea forest growing on a bank of the Ilha de Marchantaria / lower Solimões-Amazonas River, Brazil was studied in an area of slightly less than one hectare. Two biomass plots were harvested. Forty-seven arboreal species representing 46 genera in 25 families were recorded. Tree density was 1086 per hectare. Total basal area was 45 m2 ha1. Mean species density was 6.5 ± 1.98 per 100 m2. The most abundant species were Crataeva benthamii(Capparidaceae), Laetia corymbutosa(Flacourtiaceae) and Vitex cymosa(Verbenaceae). The highest basal area per species was 10.2 m2 for Pseudobombax munguba(Bombacaceae). The common species are known to be typical floristic elements of the seasonal varzea forest. Above ground dry biomass was equal to 97 and 255 t ha', respectively. Its chemical composition is characterized by comparatively high bioelement contents equal to 2.4 percent on the average. Calcium was the most important bioelement. Structure of the forest and age darings of trees allow the successional classification of the stands.

Updating of the hierarchical rock mass rating (HRMR) system and a new subsystem developed for weathered granite formations

The RMR system is still very much applied in rock mechanics engineering context. It is based on the evaluation of six weights to obtain a final rating. To obtain the final rating a considerable amount of information is needed concerning the rock mass which can be difficult to obtain in some projects or project stages at least with accuracy. In 2007 an alternative classification scheme based on the RMR, the Hierarchical Rock Mass Rating (HRMR) was presented. The main feature of this system was the adaptation to the level of knowledge existent about the rock mass to obtain the classification of the rock mass since it followed a decision tree approach. However, the HRMR was only valid for hard rock granites with low fracturing degrees. In this work, the database was enlarged with approximately 40% more cases considering other types of granite rock masses including weathered granites and based on this increased database the system was updated. Granite formations existent in the north of Portugal including Porto city are predominantly granites. Some years ago a light rail infrastructure was built in the city of Porto and surrounding municipalities whi h involved considerable challenges due to the high heterogeneity levels of the granite formations and the difficulties involved in their geomechanical characterization. In this work it is intended to provide also a contribution to improve the characterization of these formations with special emphasis to the weathered horizons. A specific subsystem applicable to the weathered formations was developed. The results of the validation of these systems are presented and show acceptable performances in identifying the correct class using less information than with the RMR system.

A new empirical system for rock slope stability analysis in exploitation stage

An empirical system was developed to obtain a quality index for rock slopes in road infrastructures, named Slope Quality Index (SQI), and it was applied to a set of real slopes.The SQI is supported in nine factors affecting slope stability that contemplate the evaluation of different parameters. Consequently, each factor is classified by the degree of importance and influence by assigned weights. These weights were established through a statistical analysis of replies to a survey that was distributed to several experienced professionals in the field. The proposed SQI varies between1 and 5, corresponding to slopes in very good and very bad condition state, respectively. Besides the advantage linked to a quantitative and qualitative evaluation of slopes, theSQI also allows identifying the most critical factors on the slope stability, which is a fundamental issue for an efficient management of the slope network in the road infrastructure, namely in the planning of conservation and maintenance operations.

SQI – A quality assessment index for rock slopes

In this work, an empirical system was developed to obtain a quality index for rock slopes in road infrastructures, named Slope Quality Index (SQI), and it was applied to a set of real slopes. The SQI is supported in nine factors affecting slope stability that contemplate the evaluation of different parameters. Consequently, each factor is classified by degree of importance and influence by assigned weights. These weights were established through a statistical analysis of replies to a survey that was distributed to several experienced professionals in the field. The proposed SQI varies between 1 and 5, corresponding to slopes in very good and very bad condition state, respectively. Besides the advantage linked to a quantitative and qualitative evaluation of slopes, the SQI also allows identifying the most critical factors on the slope stability, which is a fundamental issue for an efficient management of the slope network in the road infrastructure, namely in the planning of conservation and maintenance operations.

Mangrove vegetation in Amazonia: a review of studies from the coast of Pará and Maranhão States, north Brazil

The present study is a compilation of the literature about vegetation of mangrove forest of the north coast of Brazil. It synthesizes the knowledge about this important ecosystem and lists the currently available literature. The study focuses on the coast of Pará and Maranhão states, which are covered by a continuous belt of mangroves. The mangrove flora comprises six mangrove tree species and several associated species. Mangrove tree height and stem diameter vary as a function of abiotic local stand parameters. Seasonal variation in rainfall and salinity affect the species' phenology and litter fall. Local population use products derived from mangrove plants for different purposes (e.g. fuel; medicinal; rural construction). The increase in the coastal population has given rise to conflicts, which impact on mangrove forest.

Contribution to Early Holocene vegetation and climate history of Eastern Orinoco Llanos, Venezuela, from a paleoecological record of a Mauritia L.f. swamp

A palynological analysis of an organic paleosol found at 150-125 cm depth in a Mauritia swamp from the Eastern Orinoco Llanos is presented. The 25 cm pollen record summarizes the vegetation history during the Early Holocene, from 10,225 to 7,800 calendar yr BP. The vegetation was characterized by a Poaceae marsh, where Asteraceae, Melastomataceae, Schefflera-type and Phyllanthus were the most abundant shrubs and trees. Pollen-types richness was lower than that recorded today in similar environments, and Mauritia pollen was absent. Results suggest that climate was as humid as present during the beginning of the Holocene, with a decreasing trend in humidity from around 8,000-7,000 yr BP, in coincidence with the beginning of the "Early-Mid-Holocene Dryness" that affected deeply the Amazon Basin and neighboring areas. Dry climatic conditions could have existed in the study site until the Mid-Late Holocene when a Mauritia swamp developed, and humid conditions similar to present established. Main climate phases inferred in our study site fit well with regional trends recorded in other places located north Amazon Basin. However, conclusions are still limited by the lack of additional Quaternary records in the Orinoco Llanos area, avoiding regional correlations.

Litterfall production in intact and selectively logged forests in southern of Amazonia as a function of basal area of vegetation and plant density

Nutrient recycling in the forest is linked to the production and decomposition of litter, which are essential processes for forest maintenance, especially in regions of nutritionally poor soils. Human interventions in forest such as selecttive logging may have strong impacts on these processes. The objectives of this study were to estimate litterfall production and evaluate the influence of environmental factors (basal area of vegetation, plant density, canopy cover, and soil physicochemical properties) and anthropogenic factors (post-management age and exploited basal area) on this production, in areas of intact and exploited forest in southern Amazonia, located in the northern parts of Mato Grosso state. This study was conducted at five locations and the average annual production of litterfall was 10.6 Mg ha-1 year-1, higher than the values for the Amazon rainforest. There were differences in litterfall productions between study locations. Effects of historical logging intensity on litterfall production were not significant. Effects of basal area of vegetation and tree density on litterfall production were observed, highlighting the importance of local vegetation characteristics in litterfall production. This study demonstrated areas of transition between the Amazonia-Cerrado tend to have a higher litterfall production than Cerrado and Amazonia regions, and this information is important for a better understanding of the dynamics of nutrient and carbon cycling in these transition regions.