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This study was focused to gather the data available concerning the mortality of 440 wild animals admitted in the Wildlife Rehabilitation Centre in Parque Biológico de Gaia from 2008-2017. Only the species with unfavorable conservation status according to the Portuguese Red Book of Vertebrates were included. The animals belonged to the classes Mammalia (5.68%), Aves (86.14%), Reptilia (7.95%), and Amphibia (0.22%), 19 different orders. Overall, the most common cause of death was trauma (72%), mainly due to an unknown origin (75.5%) and shooting (2.5%). The nontraumatic causes were mainly of unknown origin (n= 18.4%) and due to nutritional problems (4.7%). Amongst the identified pressures, the proximity to a high density of small and medium companies was the most significant. There were high coefficients of redetermination (R2>0.8) which relates pressures with endangered animals’ mortality. It is, therefore, possible to conclude that according to our results human activity has an important impact on the mortality of these species.

Riverine habitats are essential ecotones that bridge aquatic and terrestrial ecosystems, providing multiple ecosystem services. This study analyses the potential use of high-resolution satellite imagery, provided by the WorldView-2 satellite, in order to assess its viability for monitoring riparian ecosystems. It is performed by calculating the riparian strip quality index (RSQI) and calibrating it with the riparian quality index (QBR). The methodology was implemented in the Umia River, which is characterised by elevated anthropogenic pressures (located in the northwest of Spain). The results obtained by the method have a 92% of veracity and a kappa coefficient of 0.88. The average quality value obtained for the RSQI index was 71.57, while the average value for the QBR was 55.88. This difference could be attributed to the fact that the former does not differ between autochthonous and non-autochthonous vegetation. The areas with more accurate mapping corresponded to stretches of vegetation with optimal cover (80–50%), with good connectivity with the adjacent forest ecosystem and few or no presence of invasive plants. The worst-scoring sites had the next characteristics: low connectivity ( Graphical Abstract

The Vilariça River was restored in order to improve the fish habitat due to the construction of dams. However, due to the pressure that agriculture exerts on water resources, it is crucial to evaluate its consequences on fish health from a histological perspective. The gonad histopathological changes of two cyprinid species were assessed microscopically and evaluated with semi-quantitative analysis. Histopathological changes in the gonad, gill, and liver were used as biomarkers in the determination of the Integrated Biomarker Response (IBR), as well as to evaluate the histopathological scores between seasons. The observation of the gonad histopathological changes showed that interstitial fibrosis and macrophage aggregates were present exclusively in the Summer and more prevalent in males of large size. In addition, the histopathological scores of the three organs were higher in the Summer. In terms of the severity degree, 98% and 68% of the fish showed pronounced and severe histopathological changes in the gill and liver, respectively, while 28% of the fish showed slight histopathological changes in the gonad. The IBR showed higher values in the Summer and in the middle stream and downstream, which is in agreement with the metal concentrations. Thus, this work showed a relationship between the anomalies present in the fish organs and the quality of the water (classified as polluted). Therefore, minimization measures are presented, such as improving the irrigation methods, preserving the vegetation cover; promoting reforestation in degraded and burned areas; and improving the riparian vegetation.

Background and Aim: Wild mammals are among the most threatened species of the world in large part due to human activity. In this work, we used the method of partial least squares-path modeling associated with a geographic information system to analyze the impact of anthropogenic pressures on the mortality of wild mammals. Materials and Methods: We collected the data related to the cause of death of native wild mammals admitted to the Wildlife Rehabilitation Centre of Parque Biológico de Gaia in Northern Portugal, during 10 years (2008-2017). Results: A total of 359 animals from 42 municipalities (rural and urban areas) were included in the study. The main cause of death was of traumatic origin. From the anthropogenic pressures included in the study, water reservoirs, small companies, and residential buildings were the ones that contributed the most to increase the mortality of traumatic and nontraumatic origin. This relation of cause-effect (mortality-anthropogenic pressures) was supported by the high coefficients of determination obtained (R2>0.8). Conclusion: The present results allow a general view on the reality of mammal's mortality in Northern Portugal. Furthermore, it could also constitute a valuable tool for the conservation of wild mammals in those areas.

The main objective of this study was to investigate the relationships between land use and future scenarios of land changes on water runoff and groundwater storage in an Environmental Protection Area (EPAs) watershed. The methodology was based on the application of the Soil and Water Assessment Tool (SWAT) hydrological modelling to investigate flow simulations in current land use and in two future scenarios (forest and pasture). The performance of goodness-of-fit indicators in the calibration (NSE = 0.82, R2 = 0.85, PBIAS = 11.9% and RSR = 0.42) and validation (NSE = 0.70, R2 = 0.72, PBIAS = -4% and RSR = 0.55) was classified as good and very good, respectively. The model accurately reproduced the inter-annual distribution of rainfall. The spatial distribution of average annual surface flow, lateral flow, and groundwater flow were different between sub-basins. The future scenario on land use change to forest (FRSE) and pasture (PAST) differed during the year, with greater changes on rainy and dry seasons. FRSE increase of 64.5% in area led to decreased surface runoff, total runoff, and soil water, and increased lateral flow, groundwater, and evapotranspiration. The effect of the natural vegetation cover on soil moisture content is still unclear. The hydrological model indicated the main areas of optimal spatial water flow. Considering economic values, those areas should encourage the development of government policies based on incentive platforms that can improve environmental soil and water sustainability by establishing payment for environmental services (PES).

Made available in DSpace on 2022-04-28T19:44:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação para a Ciência e a Tecnologia Inadequate pasture management causes land degradation through reduction of grass, increased presence of invasive plants or pests, compaction, erosion, and nutrient deficiency. The recognition of pasture degradation is therefore essential. Remote sensing satellite systems allow us to do so at regional-to global scales. A struggle is in progress nowadays is to improve detection accuracy and implement high-resolution surveys at farm scales using low-cost unmanned aerial vehicles (UAVs). The pasture imagery can be translated into maps of degraded pasture using the popular NDVI as diagnostic parameter, but their generation using a UAV requires a high-cost NIR sensor, while the struggle is to use low-cost UAVs equipped with RGB cameras. The first step to recognize degraded pastures using RGB cameras is to define a suitable vegetation index. Thus, the purpose of this study was to present the total brightness quotient of red (TBQR), green (TBQG), and blue (TBQB) bands. The test to the index resorted to LANDSAT-8 satellite images captured over the environmental protection area of Uberaba River basin (Minas Gerais, Brazil) in the 2017–2019 period. The images were not captured by a UAV because the equipment was not then available. The results were promising given the large detection accuracy (88.63%) of the TBQG and the high (0.965) correlation between TBQG and NDVI. Besides, the TBQ-based areas of degraded pasture (17,486.3–25,180.1 hectares) were larger than the NDVI counterparts (12,066.9 hectares). This is an additional reason to oversight degraded pastures based on the TBQs, as they seek for improved environmental compliance and economic development. Geoprocessing Laboratory Federal Institute of Triângulo Mineiro Uberaba Campus POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP) Regional Coordination of the Environmental Justice Prosecutor's Office of the Paranaíba and Lower Rio Grande River Basins Center for Research and Agro-environmental and Biological Technologies University of Trás-os-Montes e Alto Douro Center of Chemistry of Vila Real University of Trás-os-Montes e Alto Douro POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP) CNPq: 307921/2018-2 Fundação para a Ciência e a Tecnologia: UIDB/00616/2020 Fundação para a Ciência e a Tecnologia: UIDB/04033/2020

Made available in DSpace on 2021-06-25T11:15:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-09-01 Fundação para a Ciência e a Tecnologia This study aimed to present a payment for ecosystem services model that promotes a symbiotic coexistence between agriculture and clean water production. The model favors application to headwater catchments where clean water production is expected. However, the frequent invasion of these areas with intensive agriculture and livestock production systems affects water quality threatening the use of this resource, namely as drinking water. The proposed Agriculture for Clean Water Yield (ACWY) model reconciles agriculture with clean water production through the incentive approach, giving the farmers a financial compensation if they are willing to replace intensive by sustainable agriculture and livestock production systems, namely agro-forestry systems. The reconciliation through the incentive approach is justified because clean water and food are both vital goods for human survival. The compensation rises as function of increasing catchment water yield capacity and conversion costs. For example, landowners receive more if land conversion occurs in slopping than undulated landscapes. The model applied to Fazenda Glória watershed, composed of 19 headwater catchments (96.7 ha on average), proposed financial incentives in the range 218.73–576.5 US$/ha/year depending on the catchment's water yield capacity, which rise to 284.35–749.45 US$/ha/year if conversions occur in extreme vulnerable areas. The watershed, located in São Paulo state, Brazil, covers 18.4 km2 and is the source of drinking water to 70,000 people living in Jaboticabal city. Monitoring is essential to assess the performance of ACWY and adjust the compensation dynamically. For instance, noteworthy improvements in water yields and water quality or land conversions performed in short periods can expect the most generous compensation. Two concerns about implementing the model in Fazenda Glória rely on the lack of political will in spite of existing federal and state legal support, as well as on the financial sources to make the model a real project. Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n CITAB – Centro de Investigação e Tecnologias Agroambientais e Biológicas Universidade de Trás-os-Montes e Alto Douro, Ap. 1013 CQVR – Centro de Química de Vila Real Universidade de Trás-os-Montes e Alto Douro, Ap. 1013 POLUS – Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n POLUS – Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n Fundação para a Ciência e a Tecnologia: UIDB/00616/2020 Fundação para a Ciência e a Tecnologia: UIDB/04033/2020

Made available in DSpace on 2021-06-25T11:09:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-25 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The integration of internal (e.g., stratification) and external (e.g., pollution) factors on a comprehensive assessment of reservoir water quality determines the success of ecosystem restoration initiatives and aids watershed management. However, integrated analyses are scarcer than studies addressing factors separately. Integration is likely more efficient in studies of small well-characterized (experimental) reservoir watersheds, because the isolation of factor contributions is presumably clearer. But those studies are uncommon. This work describes the water quality of two small 5.5 m-deep reservoirs (MD-Main and VD-Voçoroca dams) located in Pindorama Experimental Center, state of São Paulo, Brazil, considering the interplay between reservoir dimension, seasonal thermal stratification, chemical gradients, erosive rainfall events, presence of natural biofilters, and land uses and landscape patterns around the reservoirs and within the contributing watersheds. The monitoring of agricultural activities and water quality parameters occurred in October 2018–July 2019. A 4 °C thermal stratification occurred in October (difference between surface and bottom water temperature), which decreased until disappearance in January (VD) or April (MD). The longer stratification period of MD was justified by its larger area relative to VD (≈10×). Thermal stratification triggered hypoxia at the bottom of both reservoirs (DO ≈ 1 mg/L), more prolonged and severe in MD. Hypoxia activated Ec and TDS peaks in January likely explained by bottom-sediment nutrient releases, presumably phosphorus. The Ec peak reached 560 μS/cm in MD and 290 μS/cm in VD. The smaller VD peak was probably explained by the action of macrophytes. In March, a 240 NTU turbidity peak occurred in MD, caused by precedent erosive rainfall and the lack of vegetation protection alongside the south border. As expected, the study accomplished clear isolation of factor contributions, verified by Factor and Cluster analyses. Our results can subsidize studies on larger reservoir watersheds requiring restoration, where the isolation of factors is more challenging. Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP) Programa de Pós-Graduação em Agronomia Ciência do Solo, Via de Acesso Prof. Paulo Donato Castellane, s/n Polo Regional Centro Norte Departamento de Descentralização do Desenvolvimento – APTA Secretaria de Agricultura e Abastecimento – SAA, Rodovia Washington Luis, Km 371, s/n Universidade Guarulhos (UNG). Programa de Mestrado em Análise Geoambiental (MAG). Praça Tereza Cristina 239 Instituto Federal do Triângulo Mineiro Campus de Uberaba Laboratório de Geoprocessamento Centro Avançado de Pesquisa do Pescado Continental - APTA, Av. Abelardo Menezes, s/n Zona Rural CITAB – Centro de Investigação e Tecnologias Agroambientais e Biológicas Universidade de Trás-os-Montes e Alto Douro, Ap. 1013 CQVR – Centro de Química de Vila Real Universidade de Trás-os-Montes e Alto Douro, Ap. 1013 POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP) Programa de Pós-Graduação em Agronomia Ciência do Solo, Via de Acesso Prof. Paulo Donato Castellane, s/n POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n CNPq: 307921/2018-2

Water resources have been increasingly impacted due to the growth of water demand associated with environmental degradation. In this context, the mapping of groundwater recharge potential has become attractive to water managers as it can be used to direct public policies and conserve this natural asset. The present study modi?es (improves) a spatially explicit model to determine groundwater recharge potential at the catchment scale, testing it in the Pandeiros River basin located in the state of Minas Gerais, Brazil. The model is generally based on the water balance approach and the input variables were compiled from institutional sources and processed in a Geographic Information System. The novelty brought by the aforementioned modi?cation relates to the coupling of physical variables (conventional way) and land management practices (introduced here) in the estimation of a percolation factor. The role of land management practices for percolation was assessed by the so-called Conservative Use Potential (PUC) method, which classi?es the areas of a river basin in terms of their potential for sustainable use. The results were validated by an independentmethod,namelytherecessioncurvemethodbasedontheinterpretationofhydrographs. In general, the groundwater recharge potential is favored in ?at to gently undulating areas and forested regions, as well as where the landscape is characterized by well-structured soils, good drainage conditions and large hydraulic conductivity. The map of groundwater recharge potential producedinthisstudycanbeusedbyplannersanddecisionmakersinthePandeirosRiverbasinasa tool to achieve sustainable use of groundwater resources and the protection of recharge areas. Made available in DSpace on 2020-04-02T00:36:46Z (GMT). No. of bitstreams: 1 Improvedmodel.pdf: 7547680 bytes, checksum: 4f23fd525910f0cea1b817bcaf0da53a (MD5) Previous issue date: 2020

The zoning of groundwater recharge potential would be attractive for water managers, but is lacking in many regions around the planet, including in the Jequitiba River basin, Minas Gerais, Brazil. In this study, a physically based spatially distributed method to evaluate groundwater recharge potential at catchment scale was developed and tested in the aforementioned Jequitiba River basin. The data for the test was compiled from institutional sources and implemented in a Geographic Information System. It comprised meteorological, hydrometric, relief, land use, and soil data. The average results resembled the annual recharge calculated by a hydrograph method, which worked as validation method. The spatial variation of recharge highlighted the predominant contribution of flat areas, porous aquifers, and forested regions to groundwater recharge. They also exposed the negative effect of urbanization. In combination, these factors elected the following sectors of the Jequitiba River basin as regions of high recharge potential: the south-southeast part of the headwaters in Prudente de Morais, Sete Lagoas towards the central part of the basin, and the region between Funil&acirc, ndia and Jequitiba, near the Jequitiba river mouth. Some management practices were suggested to improve groundwater recharge. The map of groundwater recharge potential produced in this study is valuable and is therefore proposed as tool for planners in the sustainable use of groundwater and protection of recharge areas.

Forest fires are an increasing problem over recent decades. The fires, among other consequences, lead to an increase in the soil vulnerability to water erosion and a consequent increase in sedimentation rates. When barriers are present, such as dams or weirs, there is an amplified risk of sediment and ash deposition in their reservoirs, causing siltation. Thus, there is an interest in studying in more detail the risk of siltation of barriers and reservoirs in the Douro River watershed following wildfires. A detailed barrier inventory was lacking for the Douro River, hampering the identification of siltation-prone areas. In order to fill in this gap, an extensive inventory of barriers in the Douro river basin was carried out for the present study. The result was an abundant and reliable dataset on the Douro River barriers, which allowed a prognosis on the watershed siltation risk. The method for calculating the siltation risk relied on the relationship between the frequency of forest fires, the erosion risk and the frequency of reservoirs. The sub-basins with the greater siltation risk are the T&acirc, mega, Corgo, Sousa and Paiva river basins. Most reservoirs with the highest siltation risk were from small dams. The modelling results were compared with stream connectivity and concentrations of stream water phosphorus (associated with the sediments that flow into the rivers due to the fires). With regard to connectivity, only two reservoirs were at high risk of sedimentation due to fires, so the categories of connectivity risk and fire-based sedimentation risk are probably not related. With regard to risk of high phosphorus loadings, in 8 basins the upper classes for fire-based erosion risk coincided with the upper class for phosphorus loadings suggesting that high phosphorus loading could be associated with fire-based erosion. This study works as a simple but reliable example on the assessment and mapping of siltation risk in stream networks intersected by abundant barriers. It allowed for identifying barriers that can accumulate a large quantity of fine sediments and ashes, interfering with water quality and soil erosion as well as with the storage capacity of the respective barriers.

The assessment of water availability in river basins is at the top of the water security agenda. Historically, the assessment of stream flow discharge in Brazilian watersheds was relevant for dam dimensioning, flood control projects and irrigation systems. Nowadays, it plays an important role in the creation of sustainable management plans at the catchment scale aimed to help in establishing legal policies on water resources management and water security laws, namely, those related to the payment for environmental services related to clean water production. Headwater catchments are preferential targets of these policies and laws for their water quality. The general objective of this study was to evaluate water availability in first-order sub-basins of a Brazilian headwater catchment. The specific objectives were: (1) to assess the stream flow discharge of first-order headwater sub-basins and rank them accordingly, (2) to analyze the feasibility of payment for environmental services related to water production in these sub-basins. The discharge flow measurements were conducted during five years (2012 to 2016), in headwaters in a watershed on the S&atilde, o Domingos River at the Turvo/Grande Watershed, represented as the 4th-largest hydrographic unit for water resources management&mdash, UGRHI-15 in S&atilde, o Paulo State, Brazil. A doppler velocity technology was used to remotely measure open-channel flow and to collect the data. The discharge values were obtained on periodic measurements, at the beginning of each month. The results were subject to descriptive statistics that analyzed the temporal and spatial data related to sub-basins morphometric characteristics. The discharge flows showed space&ndash, time variations in magnitude between studied headwater sub-basins on water availability, assessed based on average net discharges. The set of ecological processes supported by forests are fundamental in controlling and recharging aquifers and preserving the volume of water in headwater in each sub-basin. The upstream inflows influence downstream sub-basins. To avoid scarcity, the headwater rivers located in the upstream sub-basins must not consider basin area as a single and homogeneous unit, because that may be the source of water conflicts. Understanding this relationship in response to conservationist practices installed uphill influenced by anthropic actions is crucial for water security assessment. The headwaters should be considered a great potential for ecosystem services, with respect to the &ldquo, provider-receiver&rdquo, principle, in the context of payments for environmental services (PES).

Graphical abstract, Highlights • Existing risk validation models are based on the “spot matching” concept whereby validation is static and linked to the resemblance among spatial distribution of risky areas and regions with abnormally high nitrate concentrations; • The current model is based on the “cross-profiling” concept whereby validation is dynamic and linked to the resemblance among nitrate profiles measured along catchment flow lines and modeled counterparts obtained for specific groundwater travel times., Computer models dedicated to the validation of groundwater contamination risk in the rural environment, namely the risk of contamination by nitrate leachates from agriculture fertilizers, are frequently based on direct comparison of risky areas (e.g., cropland, pastures used for livestock production) and spatial distributions of contaminant (nitrate) plumes. These methods are fated to fail where lateral flows dominate in the landscape (mountainous catchments) displacing the nitrate plumes downhill and from the risky spots. In these cases, there is no connection between the spatial location of risky areas and nitrate plumes, unless the two locations can be linked by a contaminant transport model. The main purpose of this paper is therefore to introduce a method whereby spatio-temporal links can be demonstrated between risky areas (contaminant sources), actual nitrate plumes (contaminant sinks) and modeled nitrate distributions at specific groundwater travel times, thereby validating the risk assessment. The method assembles a couple of well known algorithms, namely the DRASTIC model [1,2] and the Processing Modflow software (https://www.simcore.com), but their combination as risk validation method is original and proved efficient in its initial application, the companion paper of Pacheco et al. [3].

In many regions across the planet, flood events are now more frequent and intense because of climate change and improper land use, resulting in risks to the population. However, the procedures to accurately determine the areas at risk in regions influenced by inadequate land uses are still inefficient. In rural watersheds, inadequate uses occur when actual uses deviate from land capability, and are termed environmental land use conflicts. To overcome the difficulty to evaluate flood vulnerability under these settings, in this study a method was developed to delineate flood vulnerability areas in a land use conflict landscape: the Batatais municipality, located in the State of S&atilde, o Paulo, Brazil. The method and its implementation resorted to remote sensed data, geographic information systems and geo-processing. Satellite images and their processing provided data for environmental factors such as altitude, land use, slope, and soil class in the study area. The importance of each factor for flood vulnerability was evaluated through the analytical hierarchy process (AHP). According to the results, vast areas of medium to high flood vulnerability are located in agricultural lands affected by environmental land use conflicts. In these areas, amplified flood intensities, soil erosion, crop productivity loss and stream water deterioration are expected. The coverage of Batatais SP municipality by these vulnerable areas is so extensive (60%) that preventive and recovery measures were proposed in the context of a land consolidation&ndash, water management plan aiming flood control and soil and water conservation.

Sustainability is a utopia of societies, that could be achieved by a harmonious balance between socio-economic development and environmental protection, including the sustainable exploitation of natural resources. The present Special Issue addresses a multiplicity of realities that confirm a deviation from this utopia in the real world, as well as the concerns of researchers. These scholars point to measures that could help lead the damaged environment to a better status. The studies were focused on sustainable use of soils and water, as well as on land use or occupation changes that can negatively affect the quality of those resources. Some other studies attempt to assess (un)sustainability in specific regions through holistic approaches, like the land carrying capacity, the green gross domestic product or the eco-security models. Overall, the special issue provides a panoramic view of competing interests for land and the consequences for the environment derived therefrom.

Gravel extraction and upstream damming caused profound effects on the estuary of the Lima river (NW Portugal) which was reflected by the collapse of banks, leading further to the destruction of riparian vegetation. This led to consequences such as a progressive negative impact on the preservation of salt marshes over several decades of this protected area, which continued even after the cessation of extraction activities. In this work, we present a restoration project combining civil engineering with soft soil engineering procedures and revegetation, along with two distinct segments, and follow the recovery process. The main intention of the study is to promote hydraulic roughness in order to dissipate energy from peak flows and tides, increasing accretion and indirectly the stimulation of plant succession and salt marsh recovery. We are able to observe that the built structures (an interconnected system of groynes, deflectors and rip-rap/gabion mattress) allowed the erosion process to be detained. However, they did not allow as much sediment as expected to be trapped. The colonization of species (plants) in brackish and tidal water was a difficulty posed by this project. A more extensive restoration of all estuarine areas and river mouths, namely to overcome the sediment deficit, will require proper land-use management at the catchment scale instead of local actions.

Interactions between pollution sources, water contamination, and ecological integrity are complex phenomena and hard to access. To comprehend this subject of study, it is crucial to use advanced statistical tools, which can unveil cause-effect relationships between pressure from surface waters, released contaminants, and damage to the ecological status. In this study, two partial least squares-path models (PLS-PM) were created and analyzed in order to understand how the cause-effect relationships can change over two seasons (summer and winter) and how the used scale (short or long) can affect the results. During the summer of 2016 and winter of 2017 surface water parameters and the North Invertebrate Portuguese Index were measured in strategic sampling sites. For each site, it two sections were delineated: the total upstream drainage area (long scale) and 250 m (short scale). For each section, data of pressures in surface waters including point source, diffuse emissions and landscape metrics were gathered. The methodology was applied to the Sabor River Basin, located in the northeast of Portugal. In this study, it was possible to determine in which season pressures affect ecological integrity and also which scale should be addressed. The models showed the influences of manganese and of potassium concentrations in stream water on the decrease in summer water quality, while arsenic’s harmful effect occurs during winter. Pastures and environmental land use conflicts were considered threats to water quality when analyzed on a long scale, whereas agricultural areas played a role when the short scale was used. The effect of landscape edge density revealed to be independent of scale or season. Effluent discharges in surface water affected the water quality during the summer season, while the effect of discharges in groundwater affected the water quality in winter. It has also been found that, to find the harmful effect of pressures, it is necessary to approach different scales and that the role of landscape metrics can also overlap contaminant sources.

Water resources are threatened by many pollution sources. The harmful effects of pollution can be evaluated through biological indicators capable of tracing problems in life forms caused by the contaminants discharged into the streams. In the present study, the effects on stream water quality of landscape configuration, season, and distance from contaminant emissions of diffuse and point sources were accessed through the evaluation of a Portuguese macroinvertebrate index (IPtIN) in 12 observation points distributed within the studied area (Ave River Basin, Portugal). Partial least-squares path models (PLS-PMs) were used to set up cause&ndash, effect relationships between this index, various metrics adapted to forest, agriculture, and artificial areas, and the aforementioned emissions, considering 13 distances from the contaminant sources ranging from 100 m to 56 km. The PLS-PM models were applied to summer and winter data to explore seasonality effects. The results of PLS-PM exposed significant scale and seasonal effects. The harmful effects of artificial areas were visible for distances larger than 10 km. The impact of agriculture was also distance related, but in summer this influence was more evident. The forested areas could hold onto contamination mainly in the winter periods. The impact of diffuse contaminant emissions was stronger during summer, when accessed on a short distance. The impact of effluent discharges was small, compared to the influence of landscape metrics, and had a limited statistical significance. Overall, the PLS-PM results evidenced significant cause&ndash, effect relationships between land use metrics and stream water quality at 10 km or larger scales, regardless of the season. This result is valid for the studied catchment, but transposition to other similar catchments needs to be carefully verified given the limited, though available, number of observation points.

Headwater catchments store valuable resources of quality water, but their hydraulic response is difficult to assess (model) because they are usually deprived of monitoring stations, namely hydrometric stations. This issue becomes even more pertinent because headwater catchments are ideal for the practice of conjunctive water resources management involving the supply of towns with groundwater and surface water, a solution that can be used to mitigate overexploitation of groundwater resources in densely urbanized and populated areas. In this study, a stepwise approach is presented whereby, in a first stage, a gauged basin was modeled for stream flow using the JAMS J2000 framework, with the purpose to obtain calibrated hydraulic parameters and ecological simulated stream flow records. Having validated the model through a comparison of simulated and measured flows, the simulated record was adjusted to the scale of an ungauged sub-basin, based on a new run of JAMS J2000 using the same hydraulic parameters. At this stage, a second validation of modeled data was accomplished through comparison of the downscaled flow rates with discharge rates assessed by field measurements of flow velocity and water column height. The modeled basin was a portion of Jequitiba River basin, while the enclosed sub-basin was the Marinheiro catchment (state of Minas Gerais, Brazil). The latter is a peri-urban watershed located in the vicinity of Sete Lagoas town, a densely urbanized and populated area. This town uses 15.5 hm3 year&minus, 1 of karst groundwater for public water supply, but the renewable resources were estimated to be 6.3 hm3 year&minus, 1. The impairment between abstraction and renewable resources lasts for decades, and for that reason the town experiences systemic water table declines and sinkhole development. The present study claims that the storage of quality water in the Marinheiro catchment, in a dam reservoir, would help alleviate the depletion of groundwater resources in the karst aquifer because this catchment could deliver 4.73 hm3 year&minus, 1 of quality surface water to the municipality without endangering ecologic flows. The construction of a small dam at the outlet of Marinheiro catchment could also improve aquifer recharge. Presently, the annual recharge in this catchment approaches 1.47 hm3 but could be much larger if the small dam was installed in the water course and the captured stream water managed properly.

The Sabor River basin is a large basin (3170 km2) located in the northeast of Portugal and used mostly for agroforestry. One problem this basin faces is a lack of water during the dry season, when there is a higher demand for water to irrigate crops. To solve this problem, the Portuguese government created a National Irrigation Program to finance new irrigation areas and improve existing ones. Consequently, it is necessary to evaluate the past and future water availability for agricultural and domestic consumption in the basin. This was done through the development of a hydrological and water allocation model. The Soil and Water Assessment Tool (SWAT) was used to model the hydrological processes that took place in the catchment between 1960 and 2008. The MIKE HYDRO Basin was used to simulate water allocation (irrigation and domestic consumption) in a historical view and under two scenarios. The historical view used the time period 1960&ndash, 2008, and the two scenarios used the same time period but with an increase in the irrigated area. The first scenario simulated the irrigation of the total irrigable area that exists in the basin. The second scenario simulated a 29% increase in the olive grove area and a 24% decrease in the resident population, according to the projection for 2060. The results show that, in the historical view, the average annual water demand deficit was 31% for domestic consumption and 70% for irrigation, which represent 1372 &times, 103 m3 and 94 &times, 106 m3 of water, respectively. In the two scenarios, the water demand deficit increased to 37% for domestic consumption and 77% for irrigation. In the first scenario, the average annual water demand deficit was 183 &times, 106 m3 of water for irrigation. In the second scenario, the average annual water demand deficit was 385 &times, 103 m3 of water for domestic consumption, and 106 &times, 106 m3 of water for irrigating the expanded olive grove area. These results demonstrate that Portuguese farmers can use our model as a decision support tool to determine how much water needs to be stored to meet the present and future water demand.

The study area used for this study was the Sabor river basin (located in the Northeast of Portugal), which is composed mostly for agroforestry. The objectives were to analyze the spatiotemporal dynamics of hydrological services that occurred due to land use changes between 1990 and 2008 and to consider two scenarios for the year 2045. The scenarios were, firstly, afforestation projection, proposed by the Regional Plan for Forest Management, and secondly, wildfires that will affect 32% of the basin area. In this work, SWAT (Soil and Water Assessment Tool) was used to simulate the provision of hydrological services, namely water quantity, being calibrated for daily discharge. The calibration and validation showed a good agreement for discharge with coefficients of determination of 0.63 and 0.8 respectively. The land use changes and the afforestation scenario showed decreases in water yield, surface flow, and groundwater flow and increases in evapotranspiration and lateral flow. The wildfire scenario, contrary to the afforestation scenario, showed an increase in surface flow and a decrease in lateral flow. The Land Use and Land Cover (LULC) changes in 2000 and 2006 showed average decreases in the water yield of 91 and 52 mm&middot, year&minus, 1, respectively. The decrease in water yield was greater in the afforestation scenario than in the wildfires scenario mainly in winter months. In the afforestation scenario, the large decrease varied between 28 hm3&middot, 1 in October and 62 hm3&middot, 1 in January, while in the wildfires scenario, the decrease was somewhat smaller, varying between 15 hm3&middot, 1 in October and 49 hm3&middot, 1 in January.

In general, this study was developed to assess the radon contamination in groundwater intended for human consumption, to raise awareness among policy-makers to implement a legal framework for drinking water management and the radiological protection of groundwater resources. Thus, we analyzed with parallel coordinate visualization (PCV) plots what features may influence the water&ndash, rock interaction and promote high-radon concentrations in water intended for human consumption. The results show that in granitic areas composed by biotite granites (Group V), although there is a higher radon production in the rocks, the radon transfer to groundwater was not effective, mainly due to the physical and chemical properties of the water. The main conclusions show that in all springs sampled (n = 69) for the entire study area, there are only four springs that must have an immediate intervention, and 22 of them are above the limit imposed by the Portuguese legislation. These results are intended to promote a Portuguese Action Plan for Radon that can be framed in the guidelines on the management and protection of groundwater resources.

The drinking water supply to Vila Pouca de Aguiar municipality in North Portugal is based on high quality groundwater, namely on nearly one hundred artesian springs and fifty boreholes. The groundwater resources are plentiful on a municipal level, but evidence some deficits at the sub-municipal (village) level, especially during the dry period (July- August) that coincides with the return of many emigrants for holiday time. The deficits affect mostly the municipal capital (Vila Pouca de Aguiar) and a neighboring village (Pedras Salgadas), which populations nearly double or even triple during that period. The estimated annual deficits approach 55,000 m3/yr in those villages. If the anticipated increase in consumption/habitant and decrease in annual rainfall become reality in the next two decades, then the deficits may raise to approximately 90,000 m3/yr. To balance the water supply system, this study proposes its transition towards a conjunctive water management based on surface water stored in small dams and groundwater. A hydrologic modeling involving small forested catchments (&lt, 15 km2) elected the Cabou&ccedil, o watershed as most suited basin to store stream water, because surface water availability is large (2.4 Mm3/yr) and forest cover is dominant (84.8%). Estimated nutrient loads are also compatible with drinking water supply.

Made available in DSpace on 2019-10-04T12:35:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) PROPE/UNESP (Pro-reitora de Pesquisa da Universidade Estadual Paulista) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) FEDER/COMPETE/POCI- Operational Competitiveness and Internationalization Programme FCT Portuguese Foundation for Science and Technology This study introduces an improved method to assess land capability in the rural environment. Land capability, also defined as natural use, is a powerfull asset in land use planning and development of land use policies, because actual land uses that deviate from natural counterparts trigger extensive and severe environmental impacts, namely amplified soil erosion and fertility decline. The proposed method builds up on a previous model based on the ruggedness number (RN), which allocates natural uses as function of increasing terrain slope and drainage density. According to the RN model, agriculture should occupy the areas of low slope and sparse drainage density, while the forest is reserved for the areas of steep slope and dense drainage. Other activities such as pasture or pasture mixed with forest can be settled on the areas of intermediate slope and drainage density. The modeling improvements introduced with this study are in a first stage related to the combination of RN-based capability classes with dissection classes derived from slope curvature estimates and landform classification (convex, concave and straight srufaces). In a second stage, the modeling improvements are related to validation of RN and landform classification schmes in the field through comparison of soil magnectic susceptibility data across the RN-dissection classes. The improved model was tested in a large multiple-landform watershed: the Tiete River basin located in Sao Paulo State (Brazil). The results proved the need to refine the RN land capability classes using the dissection classes, because dissection patterns are different across lithologic types and weather trends. In the Tiete, landscapes are generally more dissected when shaped in basaltic bedrock than in sandsone cover, and increase with increasing annual rainfall. The implications for land use planning are evident because high dissected lanscapes require more exigent conservation measures than low dissected landscapes, while suitable crop types may also vary between the two environments. The field validation of capability-dissection classes using the magnetic susceptibility proved efficient in a large portion of cases, but failed in several other sub-basins. A main reason for the failure was inadequate land use, interpreted as environmental land use conflict in this study. Overall, the current study can be viewed as major advance in the development of a land capability classification, because the integration of relief (RN), landform (dissection) and soil properties (magnetic susceptibility) has not been tempted before. The gains for land use policy are apparent because land capability maps are fundamental instruments in the management of rural areas, namely to help the mitigation of a major global concern nowadays, which is land degradation. Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Ciencias Exatas, Jaboticabal, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Engn Rural, Jaboticabal, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Solos & Adubos, Res Grp CSME Soil Characterizat Specif Management, Jaboticabal, SP, Brazil Univ Tras Os Montes & Alto Douro, CITAB, Ap 1013, P-5001801 Vila Real, Portugal Univ Brasilia, Inst Ciencias Biol, Dept Ecol, Brasilia, DF, Brazil Univ Fed Parana, Programa Posgrad Geol, Curitiba, Parana, Brazil Univ Tras Os Montes & Alto Douro, CQVR, Ap 1013, P-5001801 Vila Real, Portugal Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Ciencias Exatas, Jaboticabal, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Engn Rural, Jaboticabal, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Solos & Adubos, Res Grp CSME Soil Characterizat Specif Management, Jaboticabal, SP, Brazil FAPESP: 2016/19.215-5 CAPES: 88881.135764/2016-01 CAPES: 19/2016 CAPES: 149940 PROPE/UNESP (Pro-reitora de Pesquisa da Universidade Estadual Paulista): 15/2014 CNPq: 402796/2016-0 CNPq: 01/2016 - Faixa C FEDER/COMPETE/POCI- Operational Competitiveness and Internationalization Programme: POCI-01-0145-FEDER-006958 FCT Portuguese Foundation for Science and Technology: UID/QUI/00616/2013 FCT Portuguese Foundation for Science and Technology: UID/AGR/04033/2013

Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime, and degrading the aquatic and riparian habitats. In the present study, which comprised the Douro River basin located in the North of Portugal, the cost-benefit assessment of dams was based upon a balance between the touristic benefits of a dammed Douro, and the ecological benefits of less fragmented Douro sub-catchments. Focused on four sub-catchments (Sabor, T&acirc, mega, C&ocirc, a and Corgo), a probabilistic stream connectivity model was developed and implemented to recommend priorities for dam removal, where this action could significantly improve the movement of potadromous fish species along the local streams. The proposed model accounts for fish movement across the dam or weir (permeability), which is a novel issue in connectivity models. However, before any final recommendation on the fate of a dam or weir, the connectivity results will be balanced with other important socio-economic interests. While implementing the connectivity model, an inventory of barriers (dams and weirs) was accomplished through an observation of satellite images. Besides identification and location of any obstacles, the inventory comprised the compilation of data on surrounding land use, reservoir water use, characteristics of the riparian gallery, and permeability conditions for fish, among others. All this information was stored in a geospatial dataset that also included geographical information on the sub-catchment drainage network. The linear (drainage network) and point (barriers) source data were processed in a computer program that provided or returned numbers for inter-barrier stream lengths (habitat), and the barrier permeability. These numbers were finally used in the same computer program to calculate a habitat connector index, and a link improvement index, used to prioritize dam removal based upon structural connectivity criteria. The results showed that habitat patch connectivity in the Sabor, T&acirc, mega and C&ocirc, a sub-catchments is not dramatically affected by the installed obstacles, because most link improvement values were generally low. For the opposite reason, in the Corgo sub-catchment, obstacles may constitute a relatively higher limitation to connectivity, and in this case the removal of eight obstacles could significantly improve this connectivity. Using the probabilistic model of structural connectivity, it was possible to elaborate a preliminary selection of dams/weirs that critically limit stream connectivity, and that will be the focus of field hydraulic characterization to precisely determine fish movement along the associated river stretches. Future work will also include the implementation of a multi-criteria decision support system for dam removal or mitigation of the critical structures, as well to define exclusion areas for additional obstacles.

Made available in DSpace on 2018-12-11T16:47:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-07-01 The “polluter pays principle” (PPP) has been looked at from the perspective of legal values and technical principles, namely of soil science, to evaluate the acceleration of soil erosion and the consequent development of degraded areas in the Uberaba River basin (area: 2419 km2), state of Minas Gerais, Brazil. Having accomplished this goal, the study highlights the importance of PPP for the conservation of soil and development of an ecologically equilibrated environment. The diagnosis of degraded areas was based on the coupling of a Geographic Information System with soil loss, land use conflict and tolerance to soil loss models, and revealed a preoccupying situation because an extension of approximately 905 km2 (1/3 of the basin) has been considered in advanced state of degradation potentially causing environmental damage (e.g., decline of soil fertility and hence crop production, negative impacts of soil particles export on stream and lake water quality and biodiversity of riverine ecosystems). Facing this problem, a legal framework standing on doctrinaire principles, federal laws and the Brazilian Constitution has been proposed whereby the protagonists of soil degradation are called to assume responsibility as well as the costs of repairing this negative condition. Although the study has been carried out on a specific country under pre-defined settings, the rationale behind the proposals can easily be transposed to other scenarios because the scientific methods on which soil degradation has been defined and mapped are generally applicable, while the suggested legal values are currently applied to many regions on the planet. Promotoria de Justiça do Ministério Público do Estado de Minas Gerais UNESP—Universidade Estadual Paulista Campus de Jaboticabal Estado de São Paulo Instituto Federal do Triângulo Mineiro Uberaba Estado de Minas Gerais Centro de Investigação e Tecnologias Agroambientais e Biológicas Universidade de Trás-os-Montes e Alto Douro, Ap 1013 Centro de Química de Vila Real Universidade de Trás-os-Montes e Alto Douro, Ap 1013 UNESP—Universidade Estadual Paulista Campus de Jaboticabal Estado de São Paulo

The main purpose of this study is to compare two methodologies, DRASTIC and GOD, applied to the basin of the Cabril River in determining groundwater vulnerability to pollution. The justification for the research work in this area relates to the fact that we are facing a basin adjoining the town of Vila Real (Portugal), with a propensity to expand into this area, and where there are many springs, both near the base of the basin and in hillside areas. As a result of the application, the GOD and DRASTIC maps were obtained. To better com-pare these final vulnerability maps, the conversion of the ranges of DRASTIC indices to a normal-ized scale from 0.0 to 1.0 value was performed, staying in the same rating scale as the GOD meth-od. It was observed, through the GOD method, that the area of the basin has mostly low or negligi-ble vulnerability, related to the high depth of the groundwater level and also to the low degree of confinement. Moreover, the results of the DRASTIC method indicate that most of the basin pre-sents medium to low vulnerability, especially in areas of higher altitude. However, both methods make high vulnerability correspond to areas covered by alluvium. It may be concluded from this study that the production of results using different methods of analysis, although with similar objectives, may differ in certain locations. Thus, the outlook for the future is that the vulnerability mapping techniques ought to include physical methods, improving the credibility of these studies. O principal objetivo desse estudo é a comparação de duas metodologias, DRASTIC e GOD, aplicadas à bacia hidrográfica do rio Cabril, na determinação da vulnerabilidade das águas subterrâneas à poluição. A justificativa do trabalho, nessa região, prende-se ao facto de estarmos perante uma bacia confinante com a cidade de Vila Real (Portugal), com propensão para se expandir para essa área e onde existem muitas nascentes, tanto junto à base da bacia, como nas zonas de meia encosta. Como resultado da aplicação, obtiveram-se os mapas GOD e DRASTIC. Para melhor comparar esses mapas finais de vulnerabilidade, converteram-se os intervalos dos índices DRASTIC para uma escala normalizada de 0,0 a 1,0 valores, ficando em igual escala de classificação do método GOD. Constatou-se, através do método GOD, que a área da bacia apresenta, na sua maior parte, vulnerabilidade baixa ou desprezível, relacionada com a elevada profundidade do nível de água subterrânea e, também, com o baixo grau de confinamento. Por outro lado, os resultados do método DRASTIC indicam que grande parte da bacia apresenta vulnerabilidade média a baixa, principalmente em zonas de maior altitude. No entanto, ambos os métodos apontam para a existência de vulnerabilidade elevadas nas zonas cobertas por aluviões. O que se pode concluir do presente estudo é que a produção de resultados por métodos de análise distintos, embora com objetivos semelhantes, pode ser diferente em determinados locais. Desta forma o que se pode diagnosticar no futuro é que as técnicas de mapeamento da vulnerabili-dade deverão contemplar métodos físicos, tornando estes estudos mais credíveis.

Two simple methods of aquifer vulnerability assessment were used in this study: the GOD and AVI methods. The main purpose was to appraise their faithfulness as exploratory techniques, and their applicability to the scale of a small watershed. The study area was the Sordo River Basin (area: 50 km2), located in the Northeast of Portugal. To measure accuracy, model results were compared with vulnerability maps previously obtained for the basin, but using the standard DRASTIC model. Results of the GOD method were a map dominated by class "low vulnerability" where parameter O (overlying strata) imprinted its signature, very similar to the DRASTIC map but with smaller resolution. The method was considered valuable for exploration of primary factors of aquifer vulnerability (e.g. discrimination between water table and confined aquifers) but not for description of secondary factors (e.g. nuances in the degree of confinement). The application of the AVI method was proven inefficient because the resulting map indicated the presence of a single unrealistic class ("extremely high vulnerability"). The reason was that AVI results are evaluated on a logarithmic scale, which is appropriate for studies at regional scales where the settings are very diverse, but inappropriate for studies on the small watershed scale. O presente artigo pretende demonstrar como se pode fazer um estudo sobre a vulnerabilidade de águas subterrâneas à poluição, utilizando-se métodos diferenciados para o efeito. A análise comparativa entre metodologias e críticas construtivas tive, como base, os estudos realizados na bacia hidrográfica do rio Sôrdo, fonte de fornecimento de água para grande parte da população do nordeste de Portugal. Os métodos aplicados foram o GOD e o AVI, tendo os mapas de vulnerabilidade resultantes do primeiro evidenciado uma bacia de vulnerabilidade predominantemente baixa e os do segundo revelaram-se inconclusivos, ao apresentar uma bacia totalmente de vulnerabilidade extrema. Dessa forma, essa comparação estendeu-se ao método DRASTIC, do qual já haviam sido realizados estudos nessa área, verificando-se que os mapas são idênticos e, predominantemente, de baixa vulnerabilidade, diferenciando-se nos índices de vulnerabilidade máxima da bacia. Concluiu-se que a vulnerabilidade à poluição dos aquíferos da bacia estudada é, sobretudo, baixa, apresentando valores da ordem dos 0-0,3. Considerou-se, ainda, a aplicação do método GOD, a qual foi bem-sucedida, sendo, então, indicada para estudos mais expeditos, aconselhando-se a aplicação do método DRASTIC para estudos mais pormenorizados.

Zones of mixing between shallow groundwaters of different composition were unravelled by “two-way regionalized classification,” a technique based on correspondence analysis (CA), cluster analysis (ClA) and discriminant analysis (DA), aided by gridding, map-overlay and contouring tools. The shallow groundwaters are from a granitoid plutonite in the Fundao region (central Portugal). Correspondence analysis detected three natural clusters in the working dataset: 1, weathering; 2, domestic effluents; 3, fertilizers. Cluster analysis set an alternative distribution of the samples by the three clusters. Group memberships obtained by correspondence analysis and by cluster analysis were optimized by discriminant analysis, gridded over the entire Fundao region, and converted into “two-way regionalized classification” memberships as follows: codes 1, 2 or 3 were used when classification by correspondence analysis and cluster analysis produced the same results; code 0 when the grid node was first assigned to cluster 1 and then to cluster 2 or vice versa (mixing between weathering and effluents); code 4 in the other cases (mixing between agriculture and the other influences). Code-3 areas were systematically surrounded by code-4 areas, an observation attributed to hydrodynamic dispersion. Accordingly, the extent of code-4 areas in two orthogonal directions was assumed proportional to the longitudinal and transverse dispersivities of local soils. The results (0.7–16.8 and 0.4–4.3 m, respectively) are acceptable at the macroscopic scale. The ratios between longitudinal and transverse dispersivities (1.2–11.1) are also in agreement with results obtained by other studies.

An inventory of artesian springs emerging from fractures (fracture springs) was conducted in the Pinhao River Basin and Morais Massif, northern Portugal, comprising an area of approximately 650 km2. Over 1,500 springs were identified and associated with geological domains and fracture sets. Using cross-tabulation analysis, spring distributions by fracture sets were compared among geological environments, and the deviations related to differences in rock structure and, presumably, to differences in deformational histories. The relation between spring frequencies and rock structures was further investigated by spectral determination, the model introduced in this study. Input data are the spring frequencies and fracture lengths in each geological domain, in addition to the angles between fracture strikes and present-day stress-field orientation (θ). The model's output includes the so-called intrinsic densities, a parameter indexing spring occurrence to factors such as fracture type and associated deformational regime and age. The highest densities (12.2 springs/km of lineament) were associated with young shear fractures produced by brittle deformation, and the lowest (0.1) with old tensional and ductile fractures. Spectral determination also relates each orientation class to a dominant structural parameter: where spring occurrence is controlled by θ, the class is parallel to the present-day stress-field orientation; where the control is attributed to the length of fractures, the spring occurrence follows the strike of large-scale normal faults crossing the region.

The study area is situated in a fault zone with fractured granites and metasediments. In a conceptual model, infiltrating water first passes the bedrock cover of soil and saprolite and then partly enters the fractures. Weathering reactions of minerals occur in small pores and fissures in the bedrock cover zone to continue in the larger fractures. Pumping tests were carried out in a number of boreholes to measure the drawdown as a function of pumping time. From the results, values of transmissivity (T) could be derived. In combination with the storage coefficient (S) for similar fault zones, the hydraulic diffusivity (D = T/S) could be computed. Water samples, collected from the boreholes, represent fluid packets with a history of weathering reactions in the bedrock cover and in the larger fractures. The major element composition of these samples was used by means of the SiB mass balance algorithm (Pacheco and Van der Weijden, 1996) to calculate the moles L−1 of dissolved plagioclase (oligoclase with An ≈ 0.20) and the moles L−1 of secondary phases (gibbsite, halloysite, smectite) precipitated along the flow paths of the samples. These results were then used to calculate the net dissolved silica concentrations ([H4SiO40]) related to dissolution of plagioclase followed by precipitation of each of the secondary phases. An interpretation of a plot of each of these [H4SiO40] ’s versusD is that at D