Application of XAFS and XRD methods for describing the copper and zinc adsorption characteristics in hydromorphic soils

Environmental Geochemistry and Health - Modeling metal sorption in soils is of great importance to predict the fate of heavy metals and to assess the actual risk driven from pollution. The present...     

Determination of heavy metal levels in medicinal plant Hemerocallis minor Miller by X-ray fluorescence spectrometry

Contamination of edible plants by toxic metals is a threat for human health. We applied for the first time applied the non-destructive X-ray fluorescence spectrometry (XRF) to determine concentrations of heavy metals, i.e., Fe, Ti, Mn, Cr, Cu, Ni, Zn, Sr and Ba in plant Hemerocallis minor Miller and soils. Because this plant is used in folk medicine, the metal content assessment is important for specifying relevance of application to produce drugs. This paper considers the distribution of elements between different parts of plant (rhizome, stalk, leaves and flowers). The contents of metals were determined as varying in flowers and leaves depending on the time of sampling. The acquired concentrations of elements have been compared with toxic levels provided in literature.     

Land use and cover change in Japan and Tokyo’s appetite for meat

Urban consumption of ecosystems services such as food generates environmental impacts at different geographical scales. In the last few decades Tokyoites have shown an increasing appetite for meat. This study examines the environmental implications of Tokyo’s increasing meat consumption by analyzing how this trend has affected land use and cover change in areas near and far away. Historical databases (1970–2005) are employed in order to explore meat consumption patterns in Tokyo and to relate it with beef and pork production in areas within the country and abroad. It also integrates the historical analysis of production and consumption patterns with a discussion of the drivers (e.g., wealth, price, policies and seafood availability) behind these trends. We identified that meat production in Japan followed three distinct phases between 1877 and 2005. In the first period it took 50 years for production to increase by 50%, while during the next phase production showed the same growth in just half the time. Major changes in land use/cover change because of domestic meat production occurred mainly during the second phase and, thereafter, when domestic production declined and was substituted to a great extent by imports. Despite the increasing consumption of imported meat, Tokyo relies greatly on domestic meat produced in its neighboring prefectures. The paper concludes that regional planning can be used as an effective instrument to protect the environment and secure protein for the population of mega-urban areas such as Tokyo.     

Metal availability and uptake by sorghum plants grown in soils amended with sludge from different treatments

Several factors depending on the sludge, the soil, or the combination of both substrates, may affect element availability to plants. In this study, an assessment was done of the effect of two sludges obtained by different processes (activated sludge and facultative stabilization pond) on heavy-metal availability and uptake by sorghum plants in soils with high and low copper contents. Results obtained for DTPA-extractable metal indicated higher metal availability in sludge-amended soils. In addition, sludges caused changes in copper and zinc distribution in soil, indicating in most cases a discrete increase in the more labile metal forms. However, observed changes did not increase heavy metal concentration in plant leaves, indicating that assessment of metal availability by a chemical procedure (single extraction or metal fractionation) would not permit a good prediction of metal bioavailability. On the other hand, sludge application at a rate of 100 t ha⁻¹ to high-copper agricultural soils would not imply greater mobility of this metal on account of a greater sorbing capacity provided by the sludges. Such results would indicate that sludges from wastewater treatment plants, meeting the standards of heavy metal contents, regardless of the process by which they were obtained, may be applied to several kinds of soil, even to high-copper soils, with no risk of increasing heavy metal bioavailability to phytotoxic levels in the short range.     

Genotoxicity and toxicity assay of water sampled from a radium production industry storage cell territory by means of Allium-test

Water from natural reservoirs located near the radium production industry storage cell were analyzed using the anaphase-telophase chromosome aberration assay that was carried out on Allium schoenoprasum L. meristematic root tip cells. (262)Ra, (228)U, (232)Th, (210)Pb and (210)Po concentrations in all samples were found not to exceed the radioactivity concentration guides. The concentrations of 10 heavy metal ions were measured in water samples, but only Zn and Mn levels exceeded the maximum permissible concentration for the natural reservoirs. All water samples caused a significant increase of the chromosome aberration frequency as compared to control. The chromosome aberration spectrum analysis shows that the genotoxic effect was a result of chemical toxicity mainly. Two samples from the brook springhead were found to be toxic. The regression analysis results show that the mitotic index increased in parallel to Zn ion levels, and decreased with higher (238)U concentrations. The water samples genotoxicity positively correlated with the Zn concentration. The present work demonstrates that in order to achieve pollutant screening, it is not sufficient to determine the pollutants concentration only. Adequate conclusions on the risk due to environment contamination need to be based on the additional simultaneous use of toxicity and genotoxicity tests. When bioassays indicate some genotoxic and toxic effects, the determination of the chemical composition of the samples is then required. A combination of these two methods allows the identification of the elements that require constant biological monitoring. In the study reported here, those elements are Zn and (238)U.     

Impacts of market economy access and livelihood conditions on agro-food transition in rural communities in three macro-regions of Brazil

Environment, Development and Sustainability - Urbanization has threatened rural communities’ livelihoods worldwide, changing their agro-food systems from locally produced traditional items to...     

Assessing the risk of ignition in the Russian far east within a modeling framework of fire threat.

The forests of high biological importance in the Russian Far East (RFE) have been experiencing increasing pressure from growing demands for natural resources under the changing economy of post-Soviet Russia. This pressure is further amplified by the rising threat of large and catastrophic fire occurrence, which threatens both the resources and the economic potential of the region. In this paper we introduce a conceptual Fire Threat Model (FTM) and use it to provide quantitative assessment of the risk of ignition in the Russian Far East. The remotely sensed data driven FTM is aimed at evaluating potential wildland fire occurrence and its impact and recovery potential for a given resource. This model is intended for use by resource managers to assist in assessing current levels of fire threat to a given resource, projecting the changes in fire threat under changing climate and land use, and evaluating the efficiency of various management approaches aimed at minimizing the fire impact. Risk of ignition (one of the major uncertainties within fire threat modeling) was analyzed using the MODIS active fire product. The risk of ignition in the RFE is shown to be highly variable in spatial and temporal domains. However, the number of ignition points is not directly proportional to the amount of fire occurrence in the area. Fire ignitions in the RFE are strongly linked to anthropogenic activity (transportation routes, settlements, and land use). An increase in the number of fire ignitions during summer months could be attributed to (1) disruption of the summer monsoons and subsequent changes in fire weather and (2) an increase in natural sources of fire ignitions.     

Flood protection and endogenous sorting of households: the role of credit constraints

Human migration is increasingly seen as a promising climate change adaptation and flood risk reduction strategy. The purpose of this paper is to investigate how spatial differences in flood risk, due to differences in flood protection, reduce the mobility of vulnerable households through a credit constraint mechanism. Using an equilibrium model with two households types and endogenous sorting, we show how spatial differences in flood protection lead to clustering of vulnerable households in a risky region, in a real-world setting of common United States (US) flood zones. We find clustering effects of some size for flood zones with return periods of less than 30 years.     

Calibration for the determination of 19 trace elements in serum and urine

A fast, high-throughput and accurate method was developed for determination of Al, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, Mn, Ni, Pb, Se, U, Zn, Sb, Sn, I and Hg in urine and serum by inductively coupled plasma mass spectrometry. The samples were directly analyzed after 1/20 (v/v) dilution in 0.4% (v/v) HNO₃ and 0.005% Triton X-100. Three calibration modes were tested: aqueous and matrix matching with urine and serum. The accuracy was tested using reference materials of serum, urine and spiking. Results showed that the use of matrix matching calibration reduced the interferences and improved the recoveries for Al, Co, Pb and I in urine. The matrix matching did not affect the results considerably for serum. When serum was spiked with As, Co, Cs, Pb, U, Hg, I, Ba, Al, Cr and Ni, only matrix matching presented good recoveries. Helium was used as a collision cell gas reducing effectively polyatomic interferences for Al, Mn, Cu, Ni, Cr, Zn, As and Fe. Selection of the best internal standard was carried out for each element. The use of diluted HNO₃ improved the limit of detection. Finally, the method was applied successfully in samples of urine from workers occupationally exposed.