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Maite Garcia-Valles Meritxell Aulinas Joan B. López-Melción Andreu Moya-Garra 《Environmental science and pollution research international》2010,17(7):1287-1299
Background, aim and scope
Weathering patinas in rocks are the result of interaction processes between rock surfaces and atmosphere, biosphere and soil. Therefore, their textural and mineral composition is strongly related to environmental and bioactivity conditions. Whereas the development of weathering patinas in atmospheric conditions is well documented (e.g. typical Mediterranean patina), only very few studies focus on their formation in a burial environment. Our study of patinas developed on the tumular structure of Reguers de Seró deals with the knowledge of burial patinas from a textural and mineralogical point of view. The aims of this study include: (1) the characterisation of the rock used in this megalithic monument as well as inferences regarding the origin of the raw material; (2) the evaluation of the patinas developed on the surface of the carved steles; and (3) the discussion of the environmental conditions (atmospheric or burial) that favoured the development of the patinas. 相似文献2.
García-Algar O Zapater M Figueroa C Vall O Basagaña X Sunyer J Freixa A Guardino X Pichini S 《Journal of the Air & Waste Management Association (1995)》2003,53(11):1312-1317
Sources and concentrations of indoor nitrogen dioxide (NO2) were examined in Barcelona, Spain, during 1996-1999. A total of 340 dwellings of infants participating in a hospital-based cohort study were selected from different areas of the city. Passive filter badges were used for indoor NO2 measurement over 7-30 days. Dwelling inhabitants completed a questionnaire on housing characteristics and smoking habits. Data on outdoor NO2 concentrations were available for the entire period of the study in the areas of the city where indoor concentrations were determined. Bivariate analysis was performed to investigate relationships between indoor NO2 concentrations on one hand and outdoor NO2 concentrations, housing, and occupant characteristics on the other. Stepwise multiple linear regression was performed with variables that were found to have a significant bivariate relationship. Indoor NO2 mean values ranged between 23.57 ppb in 1996 and 27.02 ppb in 1999, with the highest yearly value of 27.82 ppb in 1997. In the same time period, mean outdoor NO2 concentration ranged between 25.26 and 25.78 ppb with a peak of 30.5 ppb in 1998. Multiple regression analysis showed that principal sources of indoor NO2 concentrations were the use of a gas cooker, the absence of an extractor fan when cooking, and cigarette smoking. The absence of central heating was also associated with higher NO2 concentrations. Finally, each ppb increase in outdoor NO2 was associated with a 1% increase in indoor concentrations. 相似文献
3.
Damásio J Barceló D Brix R Postigo C Gros M Petrovic M Sabater S Guasch H de Alda ML Barata C 《Chemosphere》2011,85(10):1548-1554
The aim of this study was to test if pharmaceuticals could explain observed responses of field collected and transplanted invertebrate species (Hydropsyche exocellata, Echinogammarus longisetosus, and Daphnia magna). The study was performed in the middle and lower course of Llobregat river basin, which is affected by pharmaceuticals and other pollutants coming from sewage treated effluents. Up to 10 different endpoints including enzyme activities related with detoxication mechanisms (i.e. glutathione S transferase, catalase, esterases), the oxidative stress damage marker (lipid peroxidation), and individual responses (mortality, post-exposure feeding rates) were assessed. Biological responses were complemented with a detailed chemical analysis of metals, detergents, pesticides, pharmaceuticals and other general water quality variables to allow identifying causal abiotic factors. Estimated hazard indexes of measured pollutants indicated that pesticides and metals accounted for most of the predicted toxicity (>95%) in the most contaminated site and that the predicted toxicity of pharmaceuticals was marginal (<5%). The three species showed a clear impact across the studied gradient indicated by higher levels of feeding inhibition and of mortality towards lower reaches. Specific responses such as inhibition of cholinesterase activities were closely related to high and presumable toxic levels of diazinon, whereas unspecific responses such as enhanced levels of antioxidant defensive mechanism and of lipid peroxidation levels were associated with most pollutant classes as well as with high and presumable toxic levels of salt and ammonia. These results indicate that pesticides, salinity, ammonia probably had greater effects on the studied species than pharmaceuticals. 相似文献
4.
Meritxell Aulinas Maite Garcia-Valles Domingo Gimeno Jose Luis Fernandez-Turiel Flavia Ruggieri Montserrat Pugès 《Environmental science and pollution research international》2009,16(4):443-452
Background, aim, and scope The first step in the restoration of a medieval stained glass window is the evaluation of its degree of degradation. This
implies the study of the chemical composition of the stained glass as well as the new mineral phases developed on its surface
(patinas). Patinas are clearly related to glass composition, time, environmental conditions, microenvironments developed in
local zones, bioactivity, physical and chemical factors, etc. This study was carried out on patinas developed in selected
Na-rich stained glass of the Santa Maria de Pedralbes Monastery (Barcelona, Spain). The location of this monument in the city
(about 5 km from the shoreline and close to the Collserola hill flank) helped to determine the environmental conditions in
which patinas developed. The aim of our study was to characterize the patinas formed on the surface of the selected glass
of this monastery in order to understand the role of the chemical composition of the original glass (Na-rich) as well as the
environmental conditions in which they developed.
Materials and methods Powdered samples of two different color-type patinas (ochre-orange and brownish) were collected in the external and internal
parts of the stained glass windows of the Prebystery and Chapter House of the Pedralbes Monastery by using a precision (odontological)
drill. These patinas were subsequently analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR).
Results XRD analyses evidenced the presence of sulfates (gypsum and thenardite), calcite, Ca-oxalates (whewellite and weddellite),
and quartz forming part of the patinas. Although these mineral phases can be found in both color-type patinas, whewellite
and thenardite are more common in the ochre-orange patinas. The results obtained were validated by the FTIR measurements.
It has been observed, when thenardite is present, that gypsum occurs as traces. Thenardite is in most of the cases associated
with whewellite and mainly occurs in the internal parts of the glass. In contrast, weddellite is limited to the absence of
thenardite and whewellite and to the external parts of the stained glass. Quartz is present in all the patinas independent
of their location and color. Calcite also occurs in many samples. It appears in both color-type patinas and, in some cases,
is associated to the presence of weddellite but not to whewellite and/or thenardite.
Discussion Glass composition together with environmental conditions and location of the patinas (internal or external parts of the stained
glass window), as well as the provenance of the glass within the monastery, are the main factors that define the development
of the new mineral phases. Moreover, the action of microorganisms, when present, can also strongly influence the development
of some mineral phases. For example, the formation of calcite in the external parts of the stained glass (associated with
the presence of oxalates) is related to the action of microorganisms. When calcite is formed in the internal parts of the
glass and it is not associated with the presence of Ca-oxalates, an inorganic origin can be invoked. The presence of weddellite
requires a very humid microenvironment with very little exposure to sunlight. In fact, this mineral phase has only been observed
in the external parts of some glass located in the humid and shady side of the monastery. Whewellite (which only appears in
the internal parts) needs a low degree of relative humidity. It has been observed that sulfur precipitating in basically one
mineral phase (thenardite or gypsum) depends on the microenvironmental conditions of the moment and the glass composition.
When thenardite occurs, it can be maintained that the original glass is of Na composition. The occurrence of quartz in all
samples is interpreted as being due to the deposition of atmospheric particulate matter. The color of the patinas can be originated
by different processes (presence of carotenes, organic pigmentation, atmospheric contamination, etc.).
Conclusions In the case of moderately weathered stained glass windows, the combination of XRD and FTIR techniques is very useful to obtain
a fast preliminary evaluation of the degree of weathering of a stained glass window. The presence of specific mineral phases
in the patina (e.g., thenardite) confirms the Na composition of the original stained glass. This is important since Na-rich
glass underwent a lesser degree of weathering than K- or K-Ca-rich glass. However, their absence cannot preclude other possibilities.
It has been extensively evidenced through time that environmental conditions play an important role on the formation of the
different mineral phases which form part of the patinas.
Recommendations and perspectives The first step in the restoration of a stained glass window is the evaluation of the degree of deterioration of the glass.
This evaluation includes a chemical analysis of the glass as well as a characterization of the patinas developed on their
surfaces. The obtained results will be essential in order to define the best restoration practices to be followed. 相似文献
5.
Joan Navarro Daniel Oro Albert Bertolero Meritxell Genovart Antonio Delgado Manuela G. Forero 《Marine Biology》2010,157(11):2453-2459
The availability of food resources has been suggested as a major factor in the substantial increase in reproductive output,
survival, recruitment and, ultimately, population growth rates in most organisms. In fact, the artificial increase in food
availability resulting from human activities has been suggested as a factor in the substantial increase in population size
of several seabirds in recent decades. In the present study, our primary aim was to estimate the importance of the main natural
prey and two alternative feeding resources, fishery discards and the invasive American crayfish Procambarus clarkii, for an opportunistic seabird, the Audouin’s gull Larus audouinii. We also assessed the influence of age and sex in the use of those three types of food. For this purpose, we compared the
analyses of δ15N and δ13C in blood of male and female adults of known age and chicks with those in their potential prey. Our results reveal sex-related
and age-related differences in the consumption of fish discards, small pelagic fish and American crayfish. Differences in
the diet of males and females and also between adults and chicks could be related to different nutritional requirements. Age
differences were probably related to their different foraging proficiency and the tendency of young breeders to opportunistically
exploit anthropogenically derived food. This study illustrates the importance of considering the age and sex of individuals
to obtain feasible dietary information and to understand how the exploitation of food of human origin could affect population
growth. 相似文献
6.
Óscar García-Algar Meritxell Zapater Cecilia Figueroa Oriol Vall Xavier Basagaña Jordi Sunyer 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1312-1317
Abstract Sources and concentrations of indoor nitrogen dioxide (NO2) were examined in Barcelona, Spain, during 1996– 1999. A total of 340 dwellings of infants participating in a hospital-based cohort study were selected from different areas of the city. Passive filter badges were used for indoor NO2 measurement over 7–30 days. Dwelling inhabitants completed a questionnaire on housing characteristics and smoking habits. Data on outdoor NO2 concentrations were available for the entire period of the study in the areas of the city where indoor concentrations were determined. Bivariate analysis was performed to investigate relationships between indoor NO2 concentrations on one hand and outdoor NO2 concentrations, housing, and occupant characteristics on the other. Stepwise multiple linear regression was performed with variables that were 1996 and 27.02 ppb in 1999, with the highest yearly value of 27.82 ppb in 1997. In the same time period, mean outdoor NO2 concentration ranged between 25.26 and 25.78 ppb with a peak of 30.5 ppb in 1998. Multiple regression analysis showed that principal sources of indoor NO2 concentrations were the use of a gas cooker, the absence of an extractor fan when cooking, and cigarette smoking. The absence of central heating was also associated with higher NO2 concentrations. Finally, each ppb increase in outdoor NO2 was associated with a 1% increase in indoor concentrations. 相似文献
7.
Joan Navarro Maite Louzao José Manuel Igual Daniel Oro Antonio Delgado José Manuel Arcos Meritxell Genovart Keith A. Hobson Manuela G. Forero 《Marine Biology》2009,156(12):2571-2578
Pelagic seabirds obtain food from oceans where the availability of their prey changes rapidly both seasonally and spatially.
Here, we investigated changes in the trophic habits of the critically endangered Balearic shearwater (Puffinus mauretanicus) through the breeding season and tested for dietary differences between sexes and age classes. We analysed δ15N and δ13C values in blood of adults during the pre-incubation, incubation and chick-rearing periods and of their chicks. Using a two-isotope
mixing model, we estimated dietary contributions based on isotope values from potential prey species which included small
pelagic species available naturally and demersal fish species available only from trawling discards. Balearic shearwaters
showed clear isotopic and dietary variation through the breeding season. During pre-incubation, breeding adults appeared to
exploit demersal fish, whereas during the incubation and chick-rearing period, they fed mainly on pelagic anchovies (Engraulis encrasicolus) and pilchards (Sardina pilchardus). Similarly, chicks were fed mainly with anchovies, a resource with a high energetic value. This variation in the dietary
habits of adult shearwaters during the breeding season was probably related to both natural and fishery-induced seasonal changes
in the availability of potential prey species within their main feeding grounds. However, changes in the nutritional requirements
of the shearwaters could also play an important role. Indeed, diet differed between sexes during pre-incubation: females fed
less on trawling discards and more on small pelagic fish than males. This sexual segregation in diet could be the consequence
of higher nutritional requirements of females during this period. Our study reveals the differential importance of both trawling
discards and small pelagic fish species for a pelagic seabird depending on the breeding period and illustrates the importance
of considering the entire breeding season when making inferences about the importance of specific prey in seabird dietary
studies. 相似文献
8.
Simone Tenan Aaron Iemma Natalia Bragalanti Paolo Pedrini Marta De Barba Ettore Randi Claudio Groff Meritxell Genovart 《Conservation biology》2016,30(6):1307-1319
The conservation of wildlife requires management based on quantitative evidence, and especially for large carnivores, unraveling cause‐specific mortalities and understanding their impact on population dynamics is crucial. Acquiring this knowledge is challenging because it is difficult to obtain robust long‐term data sets on endangered populations and, usually, data are collected through diverse sampling strategies. Integrated population models (IPMs) offer a way to integrate data generated through different processes. However, IPMs are female‐based models that cannot account for mate availability, and this feature limits their applicability to monogamous species only. We extended classical IPMs to a two‐sex framework that allows investigation of population dynamics and quantification of cause‐specific mortality rates in nonmonogamous species. We illustrated our approach by simultaneously modeling different types of data from a reintroduced, unhunted brown bear (Ursus arctos) population living in an area with a dense human population. In a population mainly driven by adult survival, we estimated that on average 11% of cubs and 61% of adults died from human‐related causes. Although the population is currently not at risk, adult survival and thus population dynamics are driven by anthropogenic mortality. Given the recent increase of human‐bear conflicts in the area, removal of individuals for management purposes and through poaching may increase, reversing the positive population growth rate. Our approach can be generalized to other species affected by cause‐specific mortality and will be useful to inform conservation decisions for other nonmonogamous species, such as most large carnivores, for which data are scarce and diverse and thus data integration is highly desirable. 相似文献
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