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31.
Regression models to predict water-soil heavy metals partition coefficients in risk assessment studies 总被引:2,自引:0,他引:2
Carlon C Dalla Valle M Marcomini A 《Environmental pollution (Barking, Essex : 1987)》2004,127(1):109-115
Risk assessment studies apply fate and transport models to predict the behaviour of chemicals in the environment. The definition of physico-chemical properties is crucial to predict the mobility of pollutants and heavy metals in particular within the environmental compartments. The conservative approach normally adopted at a screening level in attributing a value to the K(d) value, results in an extremely variable mobility in soil. In this paper a regression model to estimate rapidly the K(d) for heavy metals is proposed and applied to Pb, allowing a considerable reduction (3-4 orders of magnitude) of the estimation uncertainty. The application of a stepwise forward multiple regression to literature data provided a pH-dependent regression equation of the soil-water distribution coefficient (K(d)) for Pb: log K(d)=1.99+0.42 pH. 相似文献
32.
Yury Verlinsky Svetlana Rechitsky Serge Evsikov Melody White Jeanine Cieslak Aaron Lifchez Jorge Valle Jacob Moise Charles M. Strom 《黑龙江环境通报》1992,12(2):103-110
Preimplantation diagnosis provides couples at high genetic risk the possibility of avoiding genetic disease without the need for prenatal diagnosis and selective abortion of the affected pregnancy. Following extensive background work on the reliability of genetic diagnosis in a single cell, we offered on a research basis preimplantation diagnosis to five couples at risk for offspring with the delta-F508 mutation (the major mutation causing cystic fibrosis). There was no detrimental effect from polar body removal on either fertilization or preimplantation development. Genetic analysis, undertaken in 22 polar bodies and 15 corresponding blastomeres, identified 21 embryos of which ten were transferred. 相似文献
33.
Bustamante Mercedes M. C. Silva José Salomão Scariot Aldicir Sampaio Alexandre Bonesso Vieira Daniel Luis Mascia Garcia Edenise Sano Edson Fernandes Geraldo Wilson Durigan Giselda Roitman Iris Figueiredo Isabel Rodrigues Ricardo Ribeiro Pillar Valério D. de Oliveira Alba Orli Malhado Ana Claudia Alencar Ane Vendramini Annelise Padovezi Aurélio Carrascosa Helena Freitas Joberto Siqueira José Alves Shimbo Julia Generoso Leonel Graça Tabarelli Marcelo Biderman Rachel de Paiva Salomão Rafael Valle Raul Junior Brienza Nobre Carlos 《Mitigation and Adaptation Strategies for Global Change》2020,25(4):735-736
Mitigation and Adaptation Strategies for Global Change - The original version of the article unfortunately contained an error. 相似文献
34.
Diana Garibo Cintia Flores Xavier Cetó Beatriz Prieto-Simón Manel del Valle Josep Caixach Jorge Diogène Mònica Campàs 《Environmental science and pollution research international》2014,21(18):10652-10660
In this work, protein phosphatase inhibition assays (PPIAs) have been used to evaluate the performance of recombinant PP1 and recombinant and wild-type PP2As. The enzymes have been compared using microcystins-LR (MC-LR) as a model cyanotoxin. Whereas PP2ARec provides a limit of detection (LOD) of 3.1 μg/L, PP1Rec and PP2AWild provide LODs of 0.6 and 0.5 μg/L, respectively, lower than the guideline value proposed by the World Health Organization (1 μg/L). The inhibitory potencies of seven MC variants (-LR, -RR, -dmLR, -YR, -LY, -LW and -LF) have been evaluated, resulting on 50 % inhibition coefficient (IC50) values ranging from 1.4 to 359.3 μg/L depending on the MC variant and the PP. The PPIAs have been applied to the determination of MC equivalent contents in a natural cyanobacterial bloom and an artificially contaminated sample, with multi-MC profiles. The inhibition equivalency factors (IEFs) have been applied to the individual MC quantifications determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, and the estimated MC-LR equivalent content has been compared to PPIA results. PPIAs have demonstrated to be applicable as MC screening tools for environmental applications and to protect human and animal health. 相似文献
35.
María Pilar Martín Porrero Maria Paz Gallego-Iniesta García Jose Luis Espinosa Ruiz Araceli Tapia Valle Beatriz Cabañas Galán Maria Sagrario Salgado Muñoz 《Environmental science and pollution research international》2010,17(3):539-546
Background, aim, and scope
Acrylate and methacrylate esters are α,β-unsaturated esters that contain vinyl groups directly attached to the carbonyl carbon (CH2=CHCOO– and CH2=CCH3COO–, respectively) and are widely used in the polymer plastic and resin production. Rate coefficients for Cl reactions for most of the unsaturated esters have not been previously determined, and a good understanding is needed of all the atmospheric oxidation processes of these compounds in order to determine lifetimes in the atmosphere and to evaluate the impact of these reactions on the formation of photo-oxidants and therefore on health and environment. 相似文献36.
López Alvarez JV Aguilar Larrucea M Fernández-Carrión Quero S Jiménez del Valle A 《Waste management (New York, N.Y.)》2008,28(2):282-293
This article deals with a methodology for the design of routes for the "bin to bin" (BTB) collection of paper and cardboard waste (PCB) from small businesses, as well as with the new location and calculation of the number of containers needed in the streets for both commercial and non-commercial use due to the large amount of PCB deposited in them. This study was carried out in five shopping areas of the city of Leganés (Community of Madrid, Spain). One of the characteristics of the area is a high density of population and urban traffic. The tool used is the Geographical Information System (GIS-Arc-View). With it we can generate PCB points of high population density in commercial streets based on territorial analysis. We placed the special routes and the new container locations within a distance of 60 m of these collection points (CPT). The system calculates and optimizes six routes according to different urban restrictions. Finally, we provided service to 59% of the shops, which generate almost 82% of the PCB waste, using 160 min per day to collect 1027 kg of high quality PCB. If we compare the system with the system in place previously, we can conclude that the "bin to bin" (BTB) system improves the quality of the PCB in the containers, avoiding overflow and reducing the percentage of rejected material. 相似文献
37.
Jose de Anda Harvey Shear Ulrich Maniak Pedro F. Zdrate‐del Valle 《Journal of the American Water Resources Association》2004,40(1):97-109
ABSTRACT: Lake Chapala is the largest natural water body in Mexico and also one of the most important shallow lakes in Latin America. For the past several years it has suffered various environmental problems such as the upstream overuse of water, contamination, and sedimentation. For the past 10 years the lake has had less than 50 percent of its historical water level over the past century. No criteria are reported in the literature that establish a water storage volume that will guarantee water quality conditions necessary for the survival of the lake. After determining the behavior of total solids concentrations in relation to the variations in the lake's depth, we proposed a minimum water column height of 5.0 m, representing a storage volume of about 5,000 Mm3. This volume would result in the recommended water quality standards for total dissolved solids. Calculated distribution maps show that the total solids concentration in the lake has increased since the end of the 1970s. The solids are primarily concentrated in the eastern part of the lake, as a consequence of the high solids discharged from the Lerma River, its main tributary. 相似文献
38.
Assessing coastal vulnerability to climate change: comparing segmentation at global and regional scales 总被引:2,自引:0,他引:2
Silvia Torresan Andrea Critto Matteo Dalla Valle Nick Harvey Antonio Marcomini 《Sustainability Science》2008,3(1):45-65
Recent concerns about potential climate-change effects on coastal systems require the application of vulnerability assessment
tools in order to define suitable adaptation strategies and improve coastal zone management effectiveness. In fact, while
various research efforts were devoted to evaluate coastal vulnerability to climate change on a national to global level, fewer
applications were carried out so far to develop more comprehensive and site-specific vulnerability assessments suitable to
plan possible adaptation measures at the regional scale. In this respect, specific indicators are needed to address climate-change-related
issues for coastal zones and to identify vulnerable areas at the regional level. Two sets of coastal vulnerability indicators
were selected, one for regional and one for global studies, respectively, concerning the same features of coastal systems,
including topography and slope, geomorphological characteristics, presence and distribution of wetlands and vegetation cover,
density of coastal population and number of coastal inhabitants. The proposed set of indicators for the regional scale was
chosen taking into account the availability of environmental and territorial data for the whole coastal area of the Veneto
region and was based on site-specific datasets characterized by a spatial resolution appropriate for a regional analysis.
Moreover, a GIS-based segmentation procedure was applied to divide the coastline into linear segments, homogeneous in terms
of vulnerability to climate change and sea-level rise at the regional scale. This approach allowed to divide the Veneto shoreline
into 140 segments with an average length of about 1 km, while the global scale approach identified four coastal segments with
an average length of about 66 km. The performed comparison indicated how the more detailed approach adopted at the regional
scale is essential to understand and manage the complexities of the specific study area. In fact, the 25-m DEM employed at
the regional scale provided a more accurate differentiation of the coastal area's elevation and thus of coastal susceptibility
to the inundation risks, compared to the 1-km DEM used at the global level. Moreover, at the regional level the use of a 1:20,000
geomorphological map allowed to differentiate the unique landform class detected at the global level (e.g., fluvial plain)
in a variety of more detailed coastal typologies (e.g., open coast eroding sandy shores backed by bedrock) characterized by
a different sensitivity to climate change and sea-level rise. Accordingly, the information provided by regional indicators
can support decision-makers in improving the management of coastal resources by considering the potential impacts of climate
change and in the definition of appropriate actions to reduce inundation risks, to avoid the potential loss of valuable wetlands
and vegetation and to plan the nourishment of sandy beaches subject to erosion processes. 相似文献
39.
Esther Rubio-Portillo Maite Vázquez-Luis Carlos Valle Andrés Izquierdo-Muñoz Alfonso A. Ramos-Esplá 《Marine Biology》2014,161(10):2333-2343
The success that the putative alien species Oculina patagonica is able to survive under different environmental conditions may be benefiting its establishment and spreading along the Mediterranean Basin. Our objectives were to determine the response of this species, in terms of growth and bleaching, under different environmental conditions. Field data on colony growth and bleaching were obtained for a period of 18 months (from June 2010 to December 2011), in the Alicante Harbour (38°20′11″N, 00°29′11″W) and the Marine Protected Area of Tabarca (38°09′59″N, 00°28′56″W). Additionally, data on sedimentation rates, chlorophyll a concentration and organic matter were also collected. Moreover, the role of light over growth and bleaching of the coral was also studied with a field experiment. Our results showed that growth rates were similar among localities (eutrophic and oligotrophic environments), decreasing with increasing perimeter of the colony. Growth rates were at a minimum during cold months (13 °C) and enhanced during warm months until a threshold temperature; thereafter, bleaching was observed (>28 °C), being adverse for coral growth. In addition, light attenuation could act such as local stress, increasing the coral bleaching with the increase in seawater temperature. Our findings confirmed that O. patagonica has a broad tolerance to seawater temperature, irradiance and trophic water conditions, in addition to its ability to thrive through bleaching events, mainly in eutrophic environments, probably related to food availability. 相似文献
40.
In order to investigate the content and distribution of Hg in soils from Amazon areas not impacted by gold mining activities, the concentration and granulometric distribution of Hg were determined in three different types of soils. Hg speciation data were obtained by a thermodesorption atomic spectrometry system and the role of physico-chemical and mineralogical characteristics on Hg content were also studied. Hg concentrations found in the soil fraction <2000 microm were similar to values found in other Amazon areas without anthropogenic sources. The fine fraction (<53 microm) of podzolized soils had a higher Hg content than clayey soils. Multivariate analysis shows that there are marking differences between Spodosols of two distinct areas (fine fraction Hg contents up to 10-fold as high) indicating the importance of pedogenic processes. All statistical data analysis indicated that organic matter plays an important role in Hg accumulation in the types of soils studied. Thermodesorption analysis revealed the presence of only Hg2+, and the predominance of organically bound Hg in the majority of the studied samples. 相似文献