Search results for "Amination"
showing 10 items of 1702 documents
The individuals’ interest in preventing everyday accidents and crises : A Swedish explorative study of the importance of motivation
2014
This explorative study presents an empirical examination of the connection between motivation and the measures individuals take to prevent everyday accidents and prepare for crises. Positional factors (age and gender) and situational factors (education, size of locality, and household composition) are included because the literature highlights their importance. The study used data gathered in a 2010/2011 poll of randomly selected Swedish residents aged 16–75 (N = 2000; 44.8% response rate). A factor analysis reduced the theoretical model for situational motivation (Guay, Vallerand, & Blanchard, 2000) from four to two dimensions: motivation and amotivation. Subsequent regression analyses sta…
Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses
2011
The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for (137)Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil a…
Effects of pentachlorophenol in forest soil: a microcosm experiment for testing ecosystem responses to anthropogenic stress
1996
Changes in the structure and function of a soil decomposer community and growth of birch (Betula pendula) due to chemical contamination were studied in laboratory microcosms. Sodium pentachlorophenate (PCP) was added to the humus layer of a simulated forest soil at three nominal concentrations (0, 50 and 500 mg kg-1 dry mass). After two growing periods (48 weeks), there were more small soft-bodied mites, but less collembolans and microbial biomass, in the higher PCP concentration treatment than in the other treatments. Number of enchytraeids were significantly reduced and fungal-feeding nematodes became extinct in the soil with the higher PCP concentration. Soil respiration did not change d…
Contamination of soil by copper affects the dynamics, diversity, and activity of soil bacterial communities involved in wheat decomposition and carbo…
2009
ABSTRACT A soil microcosm experiment was conducted to evaluate the influence of copper contamination on the dynamics and diversity of bacterial communities actively involved in wheat residue decomposition. In the presence of copper, a higher level of CO 2 release was observed, which did not arise from greater wheat decomposition but from a higher level of stimulation of soil organic matter mineralization (known as the priming effect). Such functional modifications may be related to significant modifications in the diversity of active bacterial populations characterized using the DNA stable-isotope probing approach.
Different Type Clay Amendments for Lead Immobilization in Contaminated Soils
2014
Contamination with lead in soil is a crucial problem in industrial and military sites. Immobilization of lead by natural and modified clay as soil amendment can be an effective solution to this problem. Quaternary and Devonian clays were chosen for modification with NaCl, CaCl2, FeOOH and Ca10(PO4)6(OH)2 in different proportions of Ca/P equimolar ratio to test and compare immobilization efficiency of lead (II) on raw and modified clays by using a batch leaching test. The aim of the study is to compare different types of raw and modified clays as soil amendments by lead immobilization properties.
Devonian Clay Modification for the Improvement of Heavy Metal Sorption Properties
2013
Contamination with heavy metals is an important problem as bioaccumulation effects of those are creating direct and indirect hazards to environment and human health. Contaminated soil remediation can be done by various technologies and using of soil amendments is the one. Clay modification experiments were done to study heavy metal sorption from spiked solutions and leaching from contaminated soils. The aim of this paper is to give an overview of Devonian clay modification possibilities in order to improve heavy metal sorption capacity and immobilization options. Modification was done by using Ca, Na salts, HNO 3 (protonated forms), Fe-oxyhydroxide. Research has shown better sorption due to…
Selenium and heavy metals content in some Mediterranean soils
2010
Abstract The study of metal contents in industrial, agricultural or/and polluted soils compared with natural or unpolluted soils is currently necessary to obtain reference values and to assess soil contamination. Nonetheless, very few works published appear in international journals on elements like Se, Li and Sr in Spanish soils. This study determines the total levels of Se, Li, Sr, As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn, Fe, Mn and Ba in 14 natural (unpolluted) soils (Gypsisols, Leptosols, Arenosols and Acrisols), 14 agricultural soils (Anthrosols, Fluvisols and Luvisols), and 4 industrial–urban affected-surface soil horizons (Anthrosols and Fluvisols) of Eastern Spain. The geochemical baselin…
Analyse cartographique de données pédologiques et hydrogéologiques appliquée à la gestion responsable de produits phytosanitaires
2014
BASF launched a Responsible Bentazone Management plan in 2011, in order to preserve water resources and sustain its bentazon based herbicide solutions. This molecule is commercialized by the company for several years and is found at concentrations above the standard for drinking water in about 1% of groundwater catchments in France. The action plan aims to reduce contamination situations with recommendations on the use of bentazone (dose, timing of application, restrictions on vulnerable soils on groundwater catchment areas) that complement the commercialization authorization. The study carried out during the internship focused on the diagnosis of a groundwater catchment area located in the…
The dynamics of soil bacterial community structure in response to yearly repeated agricultural copper treatments
2008
International audience; The annual dynamics of soil bacterial community structure, including early, dose-dependent and transient modifications, was observed consecutively at different levels of copper contamination (high: 48 kg Cu ha−1, low: 16 kg Cu ha−1) repeated yearly over a three-year field experiment. Repeated low-level Cu contamination led to an increase in community stability to metal stress without a long-term shift in the population structure, whereas repeated high-level Cu contamination induced a novel and stable bacterial community structure. Furthermore, field experimentation highlighted that episodic climatic stress can modulate copper impact by enhancing community stability.
Horizontal distribution of copper, nickel and enchytraeid worms in polluted soil
1999
We studied the horizontal distribution of Cu, Ni and enchytraeid worms (Cognettia sphagnetorum, Vejdovsky, Oligochaeta, Enchytraeidae) in forest soil near a Cu–Ni smelter in SW Finland. Soil samples were taken from a polluted site (2 km from the smelter) and a reference area (8 km from the smelter). We used a hierarchical sampling design in the polluted area for studying possible scale-dependent variability in parameters measured, distance between the samples (different scales) being 5, 50 and 500 cm. Distribution of metals was moderately heterogeneous in the polluted soil; coefficient of variances (CV), 26% for Cu and 32% for Ni. Instead, distribution of enchytraeids in the area was highly…