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591.
S. S. Morales-García P. F. Rodríguez-Espinosa M. P. Jonathan M. Navarrete-López M. A. Herrera-García N. P. Muñoz-Sevilla 《Environmental monitoring and assessment》2014,186(1):55-67
Forty-eight air-filter samples (PM10) were analysed to identify the concentration level of partially leached metals (PLMs; As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and V) from Puebla City, México. Samples were collected during 2008 from four monitoring sites: (1) Tecnológico (TEC), (2) Ninfas (NIN), (3) Hermanos Serdán (HS) and (4) Agua Santa (AS). The results indicate that in TEC, As (avg. 424 ng m?3), V (avg. 19.2 ng m?3), Fe (avg. 1,202 ng m?3), Cu (avg. 86.6 ng m?3), Cr (41.9 ng m?3) and Ni (18.6 ng m?3) are on the higher side than other populated regions around the world. The enrichment of PLMs is due to the industrial complexes generating huge dust particles involving various operations. The results are supported by the correlation of metals (Mn, Cd and Co) with Fe indicating its anthropogenic origin and likewise, As with Cd, Co, Fe, Mn, Pb and V. The separate cluster of As, Fe and Mn clearly signifies that it is due to continuous eruption of fumaroles from the active volcano Popocatépetl in the region. 相似文献
592.
Germán A. Kopprio Gerhard Kattner R. Hugo Freije Susana José de Paggi Rubén J. Lara 《Environmental monitoring and assessment》2014,186(5):3139-3148
The seasonal variability of inorganic and organic nutrients and stable isotopes and their relations with plankton and environmental conditions were monitored in Lake Chasicó. Principal component analysis evidenced the strong influence of the river runoff on several biogeochemical variables. Silicate concentrations were controlled by diatom biomass and river discharge. Higher values of nitrate and soluble reactive phosphorus (SRP) indicated agricultural uses in the river basin. Elevated pH values (~9) inhibiting nitrification in the lake explained partially the dominance of ammonium: ~83 % of dissolved inorganic nitrogen (DIN). The low DIN/SRP ratio inferred nitrogen limitation, although the hypotheses of iron and CO2 limitation are relevant in alkaline lakes. Particulate organic matter (POM) and dissolved organic matter (DOM) were mainly of autochthonous origin. The main allochthonous input was imported by the river as POM owning to the arid conditions. Dissolved organic carbon was likely top-down regulated by the bacterioplankton grazer Brachionus plicatilis. The δ13C signature was a good indicator of primary production and its values were influenced probably by CO2 limitation. The δ15N did not evidence nitrogen fixation and suggested the effects of anthropogenic activities. The preservation of a good water quality in the lake is crucial for resource management. 相似文献
593.
Elena Crespo Pablo Lozano Julián Blasco Ignacio Moreno-Garrido 《Environmental monitoring and assessment》2014,186(8):4647-4654
Marine epibionts are organisms that grow on submerged surfaces. Those found on seagrass leaves are especially important because of their interactions with the plants, their contribution to primary production in these ecosystems, and their role as food source for heterotrophic fauna. Given the relative lack of ecotoxicological studies on epibionts, the aim of this study is to evaluate the effect of environmental pollution on epiphytes experimentally attached to artificial devices (mimes) consisting of thermally-sealed silicone tubes supported on bamboo sticks that mimic the morphology of seagrasses and serve as an anchor surface for marine epibionts. Mimes were installed on the sea floor in subtidal waters of the Rio San Pedro (Cádiz), collected after 28 days, and incubated in the laboratory with environmental concentrations of atrazine (herbicide), Irgarol (anti-fouling substance), and copper. Tube-dwelling diatoms formed the major component of the epiphyte community. Average surface covering, chlorophyll, and biomass content did not show significant differences between controls and treatments. The glutathione peroxidase activity increased significantly with 4 μg L?1 of atrazine and 5 μg L?1 of copper. This enzymatic activity increase seems to be sufficient to prevent oxidative cellular damage by removing reactive oxygen substances produced by oxidative stress; in addition to this enzyme, there might be other antioxidant enzymes which have not been measured in this study, that have also protected the organism from oxidative damage. Thus, the measurement of antioxidant enzymatic activity in epiphytes may be a useful toxicity indicator for coastal biomonitoring. 相似文献
594.
Manuela Carneiro Bruno Colaço Ricardo Brandão Carla Ferreira Nuno Santos Vanessa Soeiro Aura Colaço Maria João Pires Paula A. Oliveira Santiago Lavín 《Environmental monitoring and assessment》2014,186(11):7011-7021
The accumulation of heavy metals in the environment may have a wide range of health effects on animals and humans. Thus, in this study, the concentrations of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) in the blood and tissues (liver and kidney) of Portuguese common buzzards (Buteo buteo) were determined by inductively coupled plasma-mass spectrometer (ICP-MS) in order to monitor environmental pollution to these elements. In general, Hg and As were the elements which appeared in the highest and lowest concentrations, respectively. A highest percentage of non-detected concentration was found for blood Cd (94.6 %) but, in turn, it was the only metal that was detected in all kidney samples. The kidney was the analyzed sample which showed the highest concentrations of each element evaluated. Statistically, significant differences among blood, liver, and kidney samples were observed for As and Cd (P?0.05). Cd concentrations in kidney and liver varied significantly with age: Adults showed higher hepatic and renal Cd concentrations than juveniles. Blood Pb concentration seems to show an association with the hunting season. Although raptors are at the top of the food chain and are thus potentially exposed to any biomagnification processes that may occur in a food web, the individuals evaluated in this study generally had low levels of heavy metals in blood and tissues. However, chronic exposure to these metals was verified. The results presented here lend weight to arguments in favor of continuous biomonitoring of metals and metalloids, since heavy metals may accumulate to levels that will pose a risk to both human health and the environment. 相似文献
595.
Community metabolism in a deep (stratified) tropical reservoir during a period of high water-level fluctuations 总被引:2,自引:0,他引:2
Patricia M. Valdespino-Castillo Martín Merino-Ibarra Jorge Jiménez-Contreras Fermín S. Castillo-Sandoval Jorge A. Ramírez-Zierold 《Environmental monitoring and assessment》2014,186(10):6505-6520
As long as lakes and reservoirs are an important component of the global carbon cycle, monitoring of their metabolism is required, especially in the tropics. In particular, the response of deep reservoirs to water-level fluctuations (WLF) is an understudied field. Here, we study community metabolism through oxygen dynamics in a deep monomictic reservoir where high WLF (~10 m) have recently occurred. Simultaneous monitoring of environmental variables and zooplankton dynamics was used to assess the effects of WLF on the metabolism of the eutrophic Valle de Bravo (VB) reservoir, where cyanobacteria blooms are frequent. Mean gross primary production (P g) was high (2.2 g C m?2 day?1), but temporal variation of P g was low except for a drastic reduction during circulation attributed to zooplankton grazing. The trophogenic layer showed net autotrophy on an annual basis, but turned to net heterotrophy during mixing, and furthermore when the whole water-column oxygen balance was calculated, considering the aphotic respiration (R aphotic). The high total respiration resulting (3.1 g C m?2 day?1) is considered to be partly due to mixing enhanced by WLF. Net ecosystem production was equivalent to a net export of 3.4 mg CO2?m?2 day?1 to the atmosphere. Low water levels are posed to intensify boundary-mixing events driven by the wind during the stratification in VB. Long-term monitoring showed changes in the planktonic community and a strong silicon decrease that matched with low water-level periods. The effects of low water-level on metabolism and planktonic community in VB suggest that water-level manipulation could be a useful management tool to promote phytoplankton groups other than cyanobacteria. 相似文献
596.
M. Ausejo M. Recuero C. Asensio I. Pavón J. M. López 《Environmental Modeling and Assessment》2010,15(2):125-135
This article aims to discuss the influence of input data on the simulation model when designing Strategic Noise Maps. The
studied noise map was made in the Macrocenter of the Independent City of Buenos Aires (Argentina), which has an approximated
extension of 20 km2 and about 500,000 inhabitants. The several input data for the model are analyzed, for their quality and the lack of some
of them could affect the final result. Also, the evolution and validity of experimental measurements are analyzed when validating
a simulated map. Finally, a study of the uncertainty of the map based on the input data is made, comparing it with the recommendations
internationally adopted. 相似文献
597.
Marian Leimbach Nico Bauer Lavinia Baumstark Ottmar Edenhofer 《Environmental Modeling and Assessment》2010,15(3):155-173
Within this paper, we present the novel hybrid model REMIND-R and its application in a climate policy context based on the
EU target to avoid a warming of the Earth’s atmosphere by more than 2°C compared to the pre-industrial level. This paper aims
to identify necessary long-term changes in the energy system and the magnitude of costs to attain such a climate protection
target under different designs of the post-2012 climate policy regime. The regional specification of mitigation costs is analyzed
in the context of globalization where regions are linked by global markets for emission permits, goods, and several resources.
From simulation experiments with REMIND-R, it turns out that quite different strategies of restructuring the energy system
are pursued by the regions. Furthermore, it is demonstrated that the variance of mitigation costs is higher across regions
than across policy regimes. First-order impacts, in particular, reduced rents from trade in fossil resources, prevail regardless
of the design of the policy regime. 相似文献
598.
The concentrations of seven metals (Cd, Cr, Cu, Fe, Mn, Ni and Zn) were determined in coastal seawaters and soft and hard tissues of the barnacle Chthamalus montagui from the northwest coast of Portugal to assess the potential use of C. montagui as biomonitor of metal contamination. The results of this study showed that C. montagui soft tissues can be used for monitoring metal bioavailabilities in these coastal seawaters: (1) there were significant correlations (p?0.05) between the metal concentrations in soft tissues and their concentrations in seawaters and (2) barnacle soft tissues were sensitive to spatial variation of metal bioavailabilities, accumulating different amounts of metals in different locations. The range of concentrations in tissues were: 0.59-1.7 mg Cd kg(-1), 0.5-3.2 mg Cr kg(-1), 0.72-3.0 mg Ni kg(-1), 1.2-6.7 mg Cu kg(-1), 9-26 mg Mn kg(-1), 214-785 mg Fe kg(-1) and 178-956 mg Zn kg(-1); (3) mean logarithmic bioaccumulation factors (log BAF) of Fe, Cr and Cd were higher, 5.49, 4.93 and 4.46, respectively, than mean log BAFs of Mn, Zn, Cu and Ni, 4.03, 3.97, 3.74 and 3.61, respectively. In contrary, C. montagui shell plates were not a good matrix to monitor metal bioavailability in these coastal seawaters, with no significant correlations (p?0.05) between metal concentrations in the shell and in seawater. Regarding the high Zn concentrations obtained in the coastal seawaters and C. montagui soft tissues, all seawaters from northwest coast of Portugal should be classified as "moderately/remarkably polluted". 相似文献
599.
Waliszewski SM Caba M Herrero-Mercado M Saldariaga-Noreña H Meza E Zepeda R Martínez-Valenzuela C Gómez Arroyo S Villalobos Pietrini R 《Environmental monitoring and assessment》2012,184(9):5613-5621
The objective of the present study was to monitor the levels of organochlorine pesticides HCB; α-, β-, γ-HCH; pp'DDE; op'DDT; and pp'DDT in blood serum of Veracruz, Mexico inhabitants. Organochlorine pesticides were analyzed in 150 blood serum samples that constituted that which remained after clinical analyses, using gas chromatography-electron-capture detection (GC-ECD). The results were expressed as milligrams per kilogram on fat basis and micrograms per liter on wet weight. Only the following pesticides were detected: p,p'-DDE was the major organochlorine component, detected in 100% of samples at mean 15.8 mg/kg and 8.4 μg/L; p,p'-DDT was presented in 41.3.% of monitored samples at mean 3.1 mg/kg and 1.4 μg/L; β-HCH was found in 48.6% of the samples at mean 4.9 mg/kg and 2.7 μg/L; op'DDT was determined to be in only 3.3% of monitored samples at mean 2.7 mg/kg and 1.4 μg/L. The pooled samples divided according to sex showed significant differences of β-HCH and pp'DDE concentrations in females. The samples grouped according to age presented the third tertile as more contaminated in both sexes, indicating age as a positively associated factor with serum organochlorine pesticide levels in Veracruz inhabitants. 相似文献
600.
AA Carbonell-Barrachina A Ramírez-Gandolfo X Wu GJ Norton F Burló C Deacon AA Meharg 《Journal of environmental monitoring : JEM》2012,14(9):2447-2455
Spanish gluten-free rice, cereals with gluten, and pureed baby foods were analysed for essential macro-elements (Ca and Na), essential trace elements (Fe, Cu, Zn, Mn, Se, Cr, Co and Ni) and non-essential trace elements (As, Pb, Cd and Hg) using ICP-MS and AAS. Baby cereals were an excellent source of most of the essential elements (Ca, Fe, Cu, Mn and Zn). Sodium content was high in pureed foods to improve their flavour; fish products were also rich in Se. USA pure baby rice samples had the highest contents of all studied essential elements, showing a different nutrient pattern compared to those of other countries. Mineral fortification was not always properly stated in the labelling of infant foods. Complementary infant foods may also contain significant amounts of contaminants. The contents of Hg and Cd were low enough to guarantee the safety of these infant foods. However, it will be necessary to identify the source and reduce the levels of Pb, Cr and As in Spanish foods. Pure baby rice samples contained too much: Pb in Spain; As in UK; As, Cr and Ni in USA; and Cr and Cd in China. 相似文献