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Coimbra, Portugal

Cruzeiro C.,The Interdisciplinary Center | Cruzeiro C.,University of Porto | Rocha E.,The Interdisciplinary Center | Rocha E.,University of Porto | And 3 more authors.
Journal of Cleaner Production | Year: 2016

Estuarine environments are being constantly pressured by new sources of pollution (e.g. new pesticides) derived from the activities of industry and intensive agriculture. The present study aim at quantify pesticides of three different categories (fungicides, herbicides and insecticides) in the Tagus River basin. Seasonal transition water samples were collected during 2010 and 2011, from seven sites distributed on both margins (north and south) of this estuary. Pesticides were subjected to solid phase extraction and then analyzed using gas chromatography coupled to tandem mass spectroscopy. Data showed that 95% of the analyzed pesticides were measurable in all samples, some being above the 2013/39/EU Directive levels (total loads ranged from 1.4 μg/L, in winter, up to 5.5 μg/L, in spring). Additionally, a panel of selected physicochemical parameters-linked with water quality standards, such as total phosphorous and total nitrogen-revealed high amounts close to the Trancão River mouth. Centered on the concentration addition and independent action models, a two-tiered approach was used to assess the risk of the pesticide mixture, at the maximum concentration found. This reflected the potential risk, mainly to fish. From the results, we conclude that legal quality standards are not being followed in this emblematic ecosystem and so there are risks to the biota. Hence, refined studies are required to identify both sources and impacts of the pesticides, and also to monitor preventive and depollution measures. © 2016 Elsevier Ltd. Source


Cruzeiro C.,The Interdisciplinary Center | Cruzeiro C.,University of Porto | Rocha E.,The Interdisciplinary Center | Rocha E.,University of Porto | And 3 more authors.
International Journal of Environmental Analytical Chemistry | Year: 2015

This study describes the simultaneous quantification of 56 pesticides in surface coastal water, supported by the development and validation of a gas chromatography (GC)–ion trap (IT) mass spectrometry (MS) method. Samples (500 mL) were pre-concentrated 2500 times by solid phase extraction (OASISTMHLB). The compounds were identified and quantified, within 35 minutes, by GC tandem mass spectrometry (GC-MS/MS) and GC-MS, respectively. The methodology proved to be highly specific for all target pesticides, with an average linearity of 0.99. Detection limits and recovery rates ranged from 0.4 to 1.3 ng L− 1 and 71% to 120%, respectively. The performance of the method was checked using water samples collected from nine sampling sites along the Ria Formosa Lagoon Natural Park (south of Portugal, n = 54) in each season (2010). The total annual concentrations of all pesticides in each category (fungicides, herbicides and insecticides) were 1.4, 0.6 and 9.0 µg L−1, respectively. Moreover, 89% of the pesticides tested for were detected, 84% could be quantified and 25% had concentrations above the European recommended levels (2013/39/EU). The highest total loads of pesticides were found in the spring, which is in agreement with their seasonal application. Physicochemical parameters such as, nitrites, nitrates, ammonia and phosphates, also indicate poor water quality, supporting the fact that the Ria Formosa lagoon actually needs an effective monitoring programme for effective preservation of its natural reserve status. © 2015 Taylor & Francis. Source


Corcobado T.,University of Extremadura | Moreno G.,University of Extremadura | Azul A.M.,Center for Functional Ecology | Solla A.,University of Extremadura
Forestry | Year: 2015

Seasonal variations in ectomycorrhizal symbiosis of Quercus ilex trees were studied, with special emphasis on tree health status, Phytophthora cinnamomi root infections and topography. Five Q. ilex forests in western Spain were selected, and ca. 40 000 root tips from 3 declining and 3 non-declining trees per forest were examined. Ectomycorrhizal fungal abundance and P. cinnamomi root infections were quantified seasonally for 2 years, and an assessment was made of the water soil content and physiological status of trees during summer, the most stressful season. Seasonal changes in ectomycorrhizal fungal abundance were higher for Tomentella spp. than those for Russula spp. and Cenococcum geophilum, but these changes were not influenced by topography, tree decline status and P. cinnamomi root infections. Seasonal variations of non-vital tips were conditioned significantly by the decline status of trees. A higher proportion of non-vital tips and a lower proportion of vital non-mycorrhizal tips were observed in declining than in non-declining trees. Abundance of C. geophilum and Tomentella spp. was not influenced by P. cinnamomi root infections but by topography. Abundance of Russula spp. was not influenced by P. cinnamomi root infections but by the decline status of trees. The relationships found between tree physiology and ectomycorrhizal abundance changed significantly depending on the decline status of trees. For the first time, seasonal variations in ectomycorrhizae in P. cinnamomi-infected Q. ilex forests are reported. The low diversity and abundance of ectomycorrhizal fungi associated with declining trees should be further studied in order to uncover causes or consequences of Q. ilex crown transparency. © 2015 © Institute of Chartered Foresters, 2015. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com. Source


Ferreira P.J.T.,University of Coimbra | Gamelas J.A.F.,University of Coimbra | Carvalho M.G.V.S.,University of Coimbra | Duarte G.V.,University of Coimbra | And 2 more authors.
Industrial Crops and Products | Year: 2013

In this work, Ailanthus altissima (tree-of-heaven) wood was analyzed for its chemical, morphological and papermaking properties. The A. altissima wood was cooked under kraft conditions using different active alkali charges and then handsheets were produced with the pulps having a kappa number of 16. Based on structural, strength and optical data it was found that the kraft pulp of A. altissima is not suitable to be used alone for the production of printing and writing papers. Notwithstanding, the handsheets exhibit a favorable value of brightness in comparison to those produced from Eucalyptus globulus pulp (with similar kappa number). Therefore, the wood of A. altissima seems to have a good potential to be used as a partial substitute of the main raw material of the Portuguese pulp industry. In fact, the results showed that when beaten E. globulus and A. altissima pulps were mixed (50:50, w/w), the papermaking properties were comparable to those of beaten eucalypt kraft pulps. Therefore, the use of A. altissima wood seems promising for the production of uncoated wood-free papers, which has advantages both from an economical and environmental perspective. © 2012 Elsevier B.V. Source


Lillebo A.I.,Center for Environmental and Marine Studies | Valega M.,Center for Environmental and Marine Studies | Otero M.,Center for Environmental and Marine Studies | Pardal M.A.,Marine Life Research | And 3 more authors.
Estuarine, Coastal and Shelf Science | Year: 2010

It has been shown that salt marshes may function as efficient sinks for contaminants, namely for mercury. At the rhizo-sediment Hg may be associated with Mn and Fe oxyhydroxides, precipitated as sulphides or incorporated into organic matter. However, to our knowledge, in situ studies have not focused on the related processes at a daily or tidal cycle scales. Thus, the present work aims to study the effect of a common salt marsh halophyte in temperate latitudes (Sarcocornia perennis) on dissolved Fe, Mn and Hg concentrations in the water column. The in situ approach was carried out at a mercury-contaminated salt marsh and at the adjacent non-vegetated area (distance ≤ 4 m), covering two consecutive tidal cycles in order to include the photosynthetic active period and the night processes. During high tide no daily or spatial effects were observed on the concentrations of Mn, Fe and Hg in the water column, due to the dilution effect of the incoming seawater. During low tide the concentrations of Mn, Fe and Hg were significantly higher in the overlaying water column of the salt marsh. At S. perennis mats the concentration of dissolved total Hg was significantly related with the concentration of Mn (r = 0.459, p = 0.028, n = 23), but not with that of Fe (r = 0.367, p = 0.085, n = 23) while no significant relations were found at the adjacent non-vegetated sediments. This study highlights the complexity of the biogeochemical processes that take place in salt marshes, due to the daily photosynthetic cycle of halophytes and to the tidal action in mesotidal systems. © 2010 Elsevier Ltd. All rights reserved. Source

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