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111.
Stable oxygen and carbon isotope profiles ('18Oskeletal and '13Cskeletal), taken along the direction of growth from the umbo to the shell margin in shells of the pinnid Pinna nobilis, were used to reconstruct sea surface temperatures (SST) in the south-east Mediterranean and ontogenetic records of metabolic CO2 incorporation. Comparison of the seasonal cycle of SST, predicted from the '18Oskeletal record of a small (young) rapidly growing pinnid and temperature measured with a continuous in situ recorder showed that P. nobilis calcifies under isotopic equilibrium with surrounding seawater, thus indicating that P. nobilis shells can be used as a reliable predictor of SST. A 10-year SST record for the south-east Mediterranean was reconstructed from the shell profiles of four pinnid shells of different sizes and ages collected in 1995 and 1996. Reliable resolution of the seasonal SST could only be achieved during the first 4 years of shell growth. As the pinnids grew older, the temperature record was poorly resolved because the shell growth had diminished with age, resulting in time-averaging of the record. The amplitude of the generated seasonal temperature cycle compared favourably (DŽ°C) with a long-term temperature record from northern Mediterranean waters. Clear seasonal cycles in '13Cskeletal were observed with an amplitude of ~1.0, similar to the calculated seasonal changes in '13C of seawater (0.6) overlying seagrass meadows. An ontogenetic trend towards less positive '13Cskeletal values was too large to be attributed to any decrease in '13C in seawater resulting from the invasion of anthropogenic CO2. It is suggested that the temporal changes of '13Cskeletal are due to incorporation of respiratory CO2 into the extrapallial fluid and reflect changes in the metabolic activity of the pinnid rather than changes in the isotopic composition of dissolved inorganic carbon within the surrounding seawater. 相似文献
112.
This study examined the effect of leader-member exchange (LMX) on the relationship between employee performance (measured objectively) and the supervisor's rating of that performance. To date, no field study has tested whether high and low LMX members receive differential ratings based on their LMX relationship, beyond their actual performance. Data were collected from employees (directory assistants, cable technicians, and dispatch clerks) and their supervisors in a telephone company. The objective measures of performance which were available for these jobs were related to supervisory ratings of performance for high and low LMX employees. The results showed that poorly performing high LMX employees were given high performance ratings, regardless of their actual performance. The ratings of low LMX employees were consistent with their actual performance. The effect of LMX was more pronounced with more general task and relationship rating categories. Alternative explanations of the results, as well as the theoretical and practical implications for performance appraisal and LMX research, were discussed. 相似文献
113.
Promoting the use of environmental data collected by concerned citizens through information and communication technologies 总被引:3,自引:0,他引:3
Public participation within environmental monitoring may contribute to increasing the knowledge on the state of the environment at the same time it promotes citizens' involvement in environmental protection. However, the use of voluntary collected data is limited due to a lack of confidence in data collection procedures. Additionally, data quality is often unknown and the data are usually dispersed and non-structured. Information and communication technologies (ICT) may promote the use of voluntary collected data through the development of a collaborative system that incorporates tools and methodologies to facilitate data collection, access and validation. Furthermore, the use of ICT may promote public involvement within environmental monitoring, since it facilitates communication among all the stakeholders. This paper analyses the role of ICT in developing a system for environmental collaborative monitoring intending to promote the use of volunteer collected data. It starts by analysing the role of volunteers within environmental monitoring and continues analysing the potential of ICT to take advantage of the benefits of using data collected by citizens. A collaborative system that allows the public to express its knowledge on the state of the environment is described. Special emphasis is given to tools that explore non-traditional types of environmental data such as images, sounds and videos in association with spatial information. To illustrate the above mentioned concepts, a case study for beach quality monitoring developed within the Senses@Watch project, is described. 相似文献
114.
Godoy JM Carvalho ZL da Costa Fernandes F Danelon OM Ferreira AC Roldão LA 《Journal of environmental radioactivity》2003,70(3):193-198
The present work presents the results of 137Cs concentration in seawater, fish and sediments samples collect in 11 sampling points, crossing the Brazilian Southeastern coastal region, from Vitória (ES) to Santos (SP), on a routine basis from 1997 to 2002. This monitoring program was carried out by the Instituto de Radioproteção e Dosimetria (IRD/CNEN/MCT), in cooperation with the Instituto de Estudos do Mar Almirante Paulo Moreira (IEAPM/Brazilian Navy), aiming at determining artificial radionuclides in marine samples. Additionally to the 137Cs results, 90Sr concentrations in fish samples from 1998 to 2002 are also reported.The 137Cs in seawater follows a lognormal distribution, with a geometric mean of 1.8 Bq m-3 and a geometric standard deviation of 1.4 (n=54), decay corrected to June/2002. For 137Cs levels in fish samples a geometric mean of 0.19 Bq kg−1 and a geometric standard deviation of 2.9 (n=39), decay corrected to June/2002, with a range of 0.03 to 1.7 Bq kg−1, were obtained. Based on the 137Cs mean concentration in fish as well as in seawater, a transfer factor of 1 × 102 was calculated, which is quite in agreement with the recommended value found in the Safety Report Serie 19. 相似文献
115.
Cerqueira MA Vieira FN Ferreira RV Silva JF 《Environmental monitoring and assessment》2005,111(1-3):297-306
The aim of this study was to evaluate the water quality of the Cértima River basin (Central Portugal). For that purpose, surface
water samples were collected in March, May and July 2003, at 10 selected sampling sites, and were analysed for physicochemical
parameters, namely temperature, conductivity, pH, total suspended solids, dissolved oxygen, biochemical oxygen demand (BOD5), Kjeldahl nitrogen and total phosphorus. Results revealed an acceptable water quality during the spring season. Maxima of
64 mg dm−3 for BOD5, 39 mg dm−3 for Kjeldahl nitrogen, and 5.2 mg dm−3 for total phosphorus, were recorded during summer, indicating a significant degradation of the water quality in a river stretch
located downstream of the town of Mealhada. These values, which did not comply with the objectives of minimum quality for
surface waters prescribed by the Portuguese legislation, were related to domestic wastewater discharges and runoff waters
from a cattle farm. Besides their effects on the middle stretch of the river, these pollution sources were the most likely
cause of the high nutrient load in downstream waters, and thus may have a major impact on the trophic status of Pateira de
Fermentelos, a sensitive wetland area located in the lower Cértima basin. 相似文献
116.
Stefan Gelcich Camila Vargas Maria Jose Carreras Juan Carlos Castilla C. Josh Donlan 《Ambio》2017,46(2):184-189
Biodiversity offsets are becoming increasingly common across a portfolio of settings: national policy, voluntary programs, international lending, and corporate business structures. Given the diversity of ecological, political, and socio-economic systems where offsets may be applied, place-based information is likely to be most useful in designing and implementing offset programs, along with guiding principles that assure best practice. We reviewed the research on biodiversity offsets to explore gaps and needs. While the peer-reviewed literature on offsets is growing rapidly, it is heavily dominated by ecological theory, wetland ecosystems, and U.S.-based research. Given that majority of offset policies and programs are occurring in middle- and low-income countries, the research gaps we identified present a number of risks. They also present an opportunity to create regionally based learning platforms focused on pilot projects and institutional capacity building. Scientific research should diversify, both topically and geographically, in order to support the successful design, implementation, and monitoring of biodiversity offset programs. 相似文献
117.
Barros Ivaldete Tijolin Ceccon Juliana Parolin Glinski Andressa Liebel Samuel Grötzner Sonia Regina Randi Marco Antonio Ferreira Benedito Evanilde Ortolani-Machado Claudia Feijó Filipak Neto Francisco de Oliveira Ribeiro Ciro Alberto 《Environmental science and pollution research international》2017,24(19):16228-16240
Environmental Science and Pollution Research - In the current study, water quality of five river sites in Parana River basin (Brazil), utilized for public water supply, was assessed through a set... 相似文献
118.
Nuno C. Cruz Sónia M. Rodrigues Lina Carvalho Armando C. Duarte Eduarda Pereira Paul F.A.M. Römkens Luís A.C. Tarelho 《Environmental science and pollution research international》2017,24(17):14770-14781
Although bottom ash (BA) [or mixtures of bottom and fly ash (FA)] from clean biomass fuels is currently used as liming agent, additive for compost, and fertilizer on agricultural and forest soils in certain European countries, in several other countries most of the ashes are currently disposed in landfills. This is due to both a lack of a proper classification of the materials and of regulatory barriers.Chemical characterization including analysis of an array of potentially toxic elements (PTEs) proved that over 100,000 tons of BA currently landfilled every year in Portugal actually complied with legal limits for PTEs for soil fertilizers applied in other countries. Pot experiments were conducted, testing three dosages of BA and FA (1, 2.5, and 5%, in weight) in three mining soils with different properties. Additions of ash materials to soils led to an increase in the pore water pH relative to control pots (0% of ash added) and had a clear impact on DOC and on the solubilization of both macro- and micronutrients (notably Cu).The results from the case study using BA and FA from a Portuguese biomass thermal power plant demonstrate that it is imperative to further develop a regulatory framework to alleviate technological and environmental barriers for biomass ash utilization as raw material for fertilizers and/or soil liming agent, in accordance with the goals of the circular economy. A more harmonized view on how to assess the merits and risks of the re-use of these materials is also needed. 相似文献
119.
Ferreira José Francisco de Carvalho Corrêa Jacklinne Matta de Alcantara Junior José Ernaldo 《Environment, Development and Sustainability》2021,23(11):15725-15738
Environment, Development and Sustainability - Although sustainability assessment is widely discussed at Brazil, in Brazilian Amazon its use is still little applied, considering this territory is... 相似文献
120.
Maria Luiza Duarte Pinto Godoy José Marcus Godoy Luiz Alfredo Roldão Luiz Tauhata 《Journal of environmental radioactivity》2009
The aim of this work was to determine the concentrations and isotopic compositions of plutonium and uranium in environmental samples for safeguards purposes. An analytical method was developed with a plutonium and uranium separation procedure based on extraction chromatography (using 2 mL TEVA and UTEVA columns) and detection with a quadrupole ICP-MS applying an ultra-sonic nebulizer coupled with a membrane desolvation system. Starting from blank swipes, the background equivalent concentration (BEC) was 8 fg for 239Pu and 1 ng 238U. The method was successfully applied to certified reference materials as well as to round robin samples obtained in the framework of the inter-laboratory exercise program, promoted by the Brazilian–Argentine Agency for Accounting and Control of Nuclear Materials (ABACC), together with the US Department of Energy (USDOE). After the introduction of an additional ion-exchange separation step, the methodology was applied to the IAEA-384 sediment reference sample with precise and accurate total plutonium and uranium, 240Pu/239Pu, 241Pu/239Pu, 234U/238U and 235U/238U atomic ratio results. 相似文献