Ecosystem impacts of Alpine water intakes for hydropower: the challenge of sediment management

The natural flow hydrological characteristics (such as the magnitude, frequency, duration, timing, and rate of change of discharge) of Alpine streams, dominated by snowmelt and glacier melt, have been established for many years. More recently, the ecosystems that they sustain have been described and explained. However, natural Alpine flow regimes may be strongly modified by hydroelectric power production, which impacts upon both river discharge and sediment transfer, and hence on downstream flora and fauna. The impacts of barrages or dams have been well studied. However, there is a second type of flow regulation, associated with flow abstraction at intakes where the water is transferred laterally, either to another valley for storage, or at altitude within the same valley for eventual release downstream. Like barrages, such intakes also trap sediment, but because they are much smaller, they fill more frequently and so need to be flushed regularly. Downstream, while the flow regime is substantially modified, the delivery of sediment (notably coarser fractions) remains. The ecosystem impacts of such systems have been rarely considered. Through reviewing the state of our knowledge of Alpine ecosystems, we outline the key research questions that will need to be addressed in order to modify intake management so as to reduce downstream ecological impacts. Simply redesigning river flows to address sediment management will be ineffective because such redesign cannot restore a natural sediment regime and other approaches are likely to be required if stream ecology in such systems is to be improved.

Décision de baisser les salaires ou non: Le rôle de l'empathie face à une recommandation d'un supérieur hiérarchique (The role of Empathy in wage cut decisions).

En entreprise, les supérieurs hiérarchiques ont une influence non négligeable sur la prise de décision de leurs subordonnés. Ces derniers tendent à se conformer à l'avis de leur supérieur pour prendre leurs décisions. Toutefois, cette conformité des subordonnés à l'avis de leur supérieur peut devenir un problème lorsque l'avis reçu est questionnable d'un point de vue éthique. Les études antérieures menées à ce sujet ont démontré que le contenu n'a pas d'impact, c'est-à-dire que du moment qu'un avis est donné par un supérieur hiérarchique, les subordonnés tendent à se conformer à cet avis quelque soit son contenu. Dans la présente expérience, nous nous sommes intéressés à ce phénomène de conformité dans une prise de décision ayant des conséquences sur des personnes. En particulier, nous avons étudié le rôle de l'empathie, définit comme l'habilité de ressentir les émotions des autres ou de se mettre à leur place. Notre première hypothèse concerne l'effet principal de l'avis du supérieur : les participants tiennent compte de l'avis de leur supérieur dans leur prise de décision. Notre seconde hypothèse concerne le rôle modérateur de l'empathie: les participants haut en empathie sont moins sensibles à l'avis de leur supérieur que les participants bas en empathie étant donné qu'ils anticipent les conséquences de leur décision vis-à-vis des personnes concernées. Cent-douze étudiants ont participé à un exercice de mise en situation. Dans la peau d'un chef de Département d'une entreprise, ils devaient entre autres réfléchir au problème du niveau des salaires du personnel peu qualifié et en particulier au fait que cette catégorie de salariés était surpayée par rapport à ce qui se pratiquait sur le marché du travail. Cette expérience était composée de deux conditions, où l'avis du supérieur était manipulé. Dans la condition 1, l'avis du supérieur était de baisser les salaires, alors que dans la condition 2 l'avis était de garder les salaires constants. Les résultats ont confirmé nos hypothèses. Les participants recevant l'avis de leur supérieur de baisser les salaires ont effectivement pris la décision de baisser les salaires. Il a aussi été démontré que le niveau d'empathie modère cette relation. Les participants haut en empathie ont eu tendance à ne pas suivre l'avis donné contrairement aux participants bas en empathie. Cela démontre ainsi l'influence que peut avoir le contexte sur les individus et leur prise de décision mais aussi que les caractéristiques personnelles ont une influence non négligeable.

Crassostrea patagonica (d'Orbigny, 1842) shell concentrations from the late Miocene Rio Negro province, NE Patagonia, Argentina

The Río Negro Formation (late Miocene-early Pliocene) mainly consists of continental deposits, but it contains a middle member of marine origin. It represents a transgressive-regressive sequence that can be seen at several outcrops along the N Patagonian coast. The taphonomical approach to the El Espigón marine deposits permits the identification of four main layers containing different kinds of skeletal accumulation, which mainly consist of oyster shells [Crassostrea patagonica (D'Orbigny, 1842)]. These concentrations display three different morphologies (pouches, pavements and bouquets) with a different taphonomic signature. These deposits were formed in shallow marine environments influenced by wave activity that produced valve concentrations of different entities. They contain several shell beds that represent event, composite, hiatal to lag skeletal concentrations. Traces of bioturbation in the sediment (Thalassinoides, Teichichnus) and bioerosion on the shells (Entobia, Gastrochaeonolites, Caulostrepsis), and encrusters (cirripeds, bryozoans), are also abundant in the outcrop and consititue common components of these Miocene materials. Layers 1 and 2 of the sequence were deposited in shoreface/foreshore environments at the beginning of a highstand systems tract, while layers 3 and 4 were deposited at the end, or at the beginning of a forced regression, in foreshore environments. A final erosional episode cut the top of the layer 4, which truncated the abundant bioturbaation developed there.

Organic carbon and nutrient (P, N) concentrations of water and sediment in several aquatic environment types of a Mediterranean coastal wetland (Empordà Wetlands, NE Iberian Peninsula)

Total sediment and water organic carbon and nutrient (nitrogen and phosphorus) concentrations of different environment types of a Mediterranean coastal wetland (temporary and brackish, temporary and freshwater, semi-permanent and brackish, and permanent and brackish basins) were analysed during two hydroperiods. A nitrogen limitation was found for both sediment and water. The total organic carbon concentration of the water was significantly related to the water level, which varies throughout the hydroperiods. In contrast, the total organic carbon concentration of the sediment was not related to water level. However, significant differences in total organic carbon of the sediment were found between hydroperiods. On the other hand, total organic carbon of the sediment varied spatially, being higher in temporary brackish basins with lower sand content, and lower in permanent and semi-permanent brackish basins with higher sand content

Organochlorine pesticides in Piracicaba river basin (São Paulo/Brazil): a survey of sediment, bivalve and fish

The main objective of this paper was to evaluate the level of occurrence of the organochlorine compounds in samples of sediments, bivalves and two fish species collected in the Piracicaba River basin (São Paulo, Brazil). The isomers alpha and gamma of HCH and Heptachlor were most frequently detected in samples of sediments and specimens of bivalve and fish. Therefore, although the levels of these compounds found were not critically high, they are still found in the environment. This fact suggests that they are still being used, despite the fact that the use of these compounds was outlawed more than twenty years ago.

Validation of an analytical methodology for the quantitative analysis of petroleum hydrocarbons in marine sediment samples

This work describes a validation of an analytical procedure for the analysis of petroleum hydrocarbons in marine sediment samples. The proposed protocol is able to measure n-alkanes and polycyclic aromatic hydrocarbons (PAH) in samples at concentrations as low as 30 ng/g, with a precision better than 15% for most of analytes. The extraction efficiency of fortified sediments varied from 65.1 to 105.6% and 59.7 to 97.8%, for n-alkanes and PAH in the ranges: C16 - C32 and fluoranthene - benzo(a)pyrene, respectively. The analytical protocol was applied to determine petroleum hydrocarbons in sediments collected from a marine coastal zone.

Comparison of USEPA 3050B and ISO 14869-1: 2001 digestion methods for sediment analysis by using FAAS and ICP-OES quantification techniques

A study of the partial USEPA 3050B and total ISO 14869-1:2001 digestion methods of sediments was performed. USEPA 3050B was recommended as the simpler method with less operational risk. However, the extraction ability of the method should be taken in account for the best environmental interpretation of the results. FAAS was used to quantify metal concentrations in sediment solutions. The alternative use of ICP-OES quantification should be conditioned by a previous detailed investigation and eventual correction of the matrix effect. For the first time, the EID method was employed for the detection and correction of the matrix effect in sediment ICP-OES analysis. Finally, some considerations were made about the level of metal contamination in the area under study.

Chumbo e zinco em águas e sedimentos de área de mineração e metalurgia de metais

Lead metallurgy at Adrianópolis is the largest environmental problem of Paraná, Brazil. The objective of this study was to determine Pb and Zn levels in water and sediment in two catchments by different extraction methods. The high levels of lead in water in most of samples do not allow the human use. Total Pb concentration as high as 795.3 µg L-1 was observed in Ribeira River bank, in a pluvial water stream flowering from a abandoned factory. Due to the high Pb levels in sediments from some sites (maximum of 24,300 mg kg-1) is recommended to avoid the water turbulence.

Monitoring of praseodymium(III) ions in aqueous solutions, soil and sediment samples by a PVC membrane sensor based on a furan-triazole derivative

A furan-triazole derivative has been explored as an ionophore for preparation of a highly selective Pr(III) membrane sensor. The proposed sensor exhibits a Nernstian response for Pr(III) activity over a wide concentration range with a detection limit of 5.2×10-8 M. Its response is independent of pH of the solution in the range 3.0-8.8 and offers the advantages of fast response time. To investigate the analytical applicability of the sensor, it was applied successfully as an indicator electrode in potentiometric titration of Pr(III) solution and also in the direct and indirect determination of trace Pr(III) ions in some samples.

Characterization of Citrus tristeza virus isolates from grapefruit (Citrus paradisi Macf.) accessions of Citrus Active Germplasm Bank

Citrus tristeza virus (CTV) isolates from 35 grapefruit accessions belonging to Citrus Active Germplasm Bank of the "Instituto Agronômico de Campinas" located at the "Centro APTA Citros Sylvio Moreira", Cordeirópolis, São Paulo state, Brazil, were characterized and evaluated through symptoms in the trees, biological indexing, immunological diagnosis with different monoclonal antibodies and SSCP analysis (single-strand conformation polymorphism) of the coat protein gene. Symptomatology indicated that, in general, the group of plants with smaller canopy volume and severe stem pitting differed significantly from the group that presented greater vegetative development and mild to moderate stem pitting. However, the isolates from most of the accessions induced mild reaction on Mexican lime. The serological evaluation through the DAS-ELISA using monoclonal antibodies did not reveal any association between virus titer in the plant tissue and symptoms. The reaction with different monoclonal antibodies and the distinct electrophoresis patterns obtained through SSCP showed that there is a high degree of diversity among the isolates that infect these grapefruit accessions. High complexity within the same isolate was also observed in the SSCP profiles. This finding indicates that the CTV isolates from these plants are a complex mixture of CTV haplotypes. Similar SSCP banding patterns were observed among some plants with strong stem pitting symptoms, and among some plants with weak or moderate stem pitting symptoms.

Speaking Wounds – Silence, Self-injury and Healing in Patricia McCormick‟s Cut

Pro gradu -tutkielmani käsittelee itsensä vahingoittamisen, hiljaisuuden ja toipumisen representaatioita Patricia McCormickin nuorille aikuisille suunnatussa teoksessa Cut. Tutkielman tarkoituksena on analysoida itsensä vahingoittamista kirjallisuudentutkimuksellisesta näkökulmasta. Vaikka itsensä vahingoittamisesta on englanninkielisillä markkinoilla olemassa runsaasti psykologista kirjallisuutta, ei sen representaatioita kirjallisuudessa ole vielä juurikaan tutkittu. Näiden representaatioiden analysointi on tärkeää, sillä 1990-luvun alkupuolella syntyi nuortenkirjallisuudessa genre, joka keskittyy juuri itsensä vahingoittamisen käsittelyyn. Patricia McCormickin Cut on edustava esimerkki tämän genren romaanista. Tutkimuksen teoreettinen viitekehys koostuu monitieteellisistä teksteistä. Ensisijaisina lähteinä ovat Patrick Fueryn teoreettiset käsitykset hiljaisuudesta ja poissa-olosta sekä Christine Wilkie-Stibbsin feministiset luennat yksittäisistä nuortenkirjoista. Armando R. Favazzan kliiniset määritelmät itsensä vahingoittamisesta luovat perustan käyttämilleni termeille. Pääpaino tutkielmassa on kuitenkin omalla luennallani romaanista. Tutkimustuloksena on, että sekä päähenkilön hiljaisuus että itsensä viiltely ovat monimerkityksisiä ja dynaamisia tiloja. Ne toimivat kommunikaation ja itsehoidon välineinä. Viiltelyyn sisältyy voimakkaasti hoivan käsite, sillä viiltämällä itseään päähenkilö yrittää käsitellä ja helpottaa henkistä ahdistustaan. Sekä hiljaisuus että viiltely auttavat eri tavoin päähenkilöä käsittelemään ja sisäistämään oman tilansa ja näin ollen myös edistävät paranemisprosessia, joka jatkuu puheen kautta perinteisessä psykoterapeuttisessa diskurssissa. Teos painottaa puheen roolia, mutta myös hiljaisuus ja viiltely muodostavat yhtäläiset kommunikaatio- ja hoitoväylät.

Riparian vegetation affected by bank erosion in the Lower São Francisco River, Northeastern Brazil

Changes in the hydrological regime of the Lower São Francisco River, located in Northeastern Brazil have brought negative environmental impacts, jeopardizing the flora and fauna of a global biodiversity hotspot, due to implementation of hydroelectric power dams and surface water withdrawal for irrigation in public and private perimeters. Remnants of the riparian stratum associated to the riverbank destabilization in six fragments were studied by surveying trees, shrubs, herbs, and aquatic species. The calculation of the Factor of Safety (FS) was performed in order to understand the riverbank's stability related to soil texture and vegetation cover. An overall number of 51 botanic families distributed in 71 genera and 79 species were recorded, predominantly from the families Mimosaceae, Myrtaceae, and Fabaceae. The fragmented riparian vegetation is mostly covered by secondary species under a strong anthropogenic impact such as deforestation, mining and irrigation, with an advanced erosion process in the river margins. Strong species that withstand the waves present in the river flow are needed to reduce the constant landslides that are mainly responsible for the river sedimentation and loss of productive lands. A lack of preservation attitude among the local landholders was identified, and constitutes a continuing threat to the riparian ecosystem biodiversity.

Turbidimetry as an alternative method to determine the rating curve of suspended sediments

Understanding hydrosedimental behavior of a watershed is essential for properly managing and using its hydric resources. The objective of this study was to verify the feasibility of the alternative procedure for the indirect determination of the sediment key curve using a turbidimeter. The research was carried out on the São Francisco Falso River, which is situated in the west of the state of Paraná on the left bank of ITAIPU reservoir. The direct method was applied using a DH-48 sediment suspended sampler. The indirect method consisted of the use of a linigraph and a turbidimeter. Based on the results obtained, it was concluded that the indirect method using a turbidimeter showed to be fully feasible, since it gave a power function-type mathematical model equal of the direct method. Furthermore, the average suspended sediment discharge into the São Francisco Falso River during the 2006/2007 harvest was calculated at 7.26 metric t day-1.