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681.
The uptake of 109Cd and 65Zn and their stable isotopes by ryegrass (Lolium multiflorum Lam.), grown on two different soil types, was investigated in climatically controlled growth chambers at 9 and 21 degrees C. The soils were treated with 0 and 4% organic matter (pig [Sus scrofa] manure) and spiked with 109Cd and 65Zn before sowing. The organic matter addition resulted in increased uptake of the 109Cd, Cd, and Zn by ryegrass, but the uptake of 65Zn was decreased. The latter effect was ascribed to isotopic dilution of 65Zn as the amount of stable Zn in the plant tissues increased with the organic matter addition. The effect of temperature was more pronounced than that of organic matter addition, and the uptake of both 109Cd and 65Zn and their stable isotopes was higher in ryegrass grown at 21 degrees C than that grown at 9 degrees C. Results from fractionation and speciation analysis of soil cadmium and zinc were correlated with plant uptake, and there was a good consistency between observed plant uptake and the physico-chemical forms of cadmium and zinc in soil and soil solution presumed to be plant available. 相似文献
682.
2 semiarid irrigated area with salt-affected soils. The available soil map is at 1:100,000 scale and its mapping units are
used for the land evaluation with the FAO framework. These data are then elaborated using the index value method. This procedure
gives a map of land evaluation units and a table that rates the productive potential of these units for six crops: alfalfa,
barley, maize, rice, sunflower, and wheat. 相似文献
683.
Andréa MM Peres TB Luchini LC Pettinelli A 《Journal of environmental science and health. Part. B》2000,35(3):297-307
The soil oxidative and anaerobic processes, as well as, the microbial biomass were followed during three years in a cotton farm (Tatuí) where the recommended pesticides have been used for several years, and in an experimental field (S?o Paulo) treated first time with the same pesticides. The oxidative process was monitored by the dehydrogenase (DHA)-activity using triphenyltetrazolium chloride (TTC) as substrate. The anaerobic process was followed by the iron-oxide reduction, and the microbial biomass was estimated by the substrate (glucose)-indiced respiration. Increases in DHA-activity and in the microbial biomass occurred only in the farm soil, with concomitant decreases in iron-reduction. In the experimental field soil, the increases in DHA-activity were followed only by decreases in iron-reduction. Soil characteristics were the determining factor for different biological parameters after pesticide inputs. All the pesticides produced at least one clear but transient effect. 相似文献
684.
Concentrations of Pb in livers of willow grouse (Lagopus lagopus), black grouse (Tetrao tetrix), and hare (Lepus timidus) were determined in samples collected during the period 1990-92 from 77 locations distributed across Norway. Our objective was to elucidate the impact of long-range atmospheric transport on the Pb exposure of the animals. The moss Hylocomium splendens was measured for atmospheric Pb deposition and Pb in soil at 60-cm depth was determined to reflect the natural geochemical background at the study locations. Strong positive relationships were found between Pb in liver and atmospheric deposition of Pb for all species and age groups studied. Results indicate that long-range atmospheric transport was the main source of Pb in the animals studied. This conclusion was supported by Pb analysis of typical food plants for the animals. Correlation between Pb in liver and Pb in soil mineral matter was observed only when considering sites with very low impact of atmospheric deposition. Even though the observed liver Pb concentrations may seem low (< or =12 microg g(-1) dw) they approach levels where sub-lethal effects cannot be ignored. 相似文献
685.
J. L. Bardasano J. Álvarez-Ude I. Gutiérrez M. Raposo R. Goya 《The Environmentalist》2007,27(4):519-523
Objectives This paper aims to provide evidence of an inductive electromagnetic bioeffect on the human brain, which is independent from
sound waves and produced by mobile phones, in proximal field, through correlating the EEG data obtained from electrodes placed
on both normal and cochlear deaf individuals.
Methods Two groups of subjects are placed under controlled electromagnetic conditions inside a Faraday chamber, 12 healthy and another
12 suffering from cochlear deafness). Each is sitting on a chair, fitted with additional support, and holding a cellular phone
2 cm away form the right auricular, in order to avoid a thermal effect as much as possible. All of them, relaxed and with
their eyes closed, are EEG recorded in a basal state with their mobile phones off. Then, each of them is again recorded under
the same conditions but with the mobile on and listening to the same conversation. In order to assess the observed EEG changes,
a statistical analysis by means of the FFT (Fast Fourier Transform) was carried out.
Results For both, healthy and cochlear deaf, assimilation or integration of the mobile phone signal by some electrodes is to be found.
This is due to the increase of amplitudes for alpha and theta waves, whereas the signal is not integrated in other electrodes.
By correlating the spectra of frequencies of corresponding EEG records for the same brain areas, we have not observed significative
differences for both groups.
Conclusions A possible electromagnetic direct inductive, non-thermal, bioeffect on the human brain is observed. This effect is produced
by the use of mobile phones and it bears no relation to the sound waves. 相似文献
686.
Without any incentive to clean up a contaminated site, remediation is often delayed until the site owner is compelled to act by regulatory agencies. In such a context, the selected technology is typically the one that will reach the remediation goals as quickly as possible. Unfortunately, this criterion is often met by overly expensive technologies, resulting in high and sometimes unaffordable total remediation costs, leading to a remediation with a negative net benefit. This study examines the effects of time constraint and benefit value on the optimal remediation strategy for a diesel-contaminated site. This strategy is developed using the technico-economic model METEORS, which takes into account the technology’s effectiveness, the uncertainty of the level of contamination, and the possibility of reducing this uncertainty through either an additional characterization (before selecting and applying a technology) or the monitoring of the remediation technology (during its use). Results of simulations with both economic and temporal constraints support a proactive approach to site remediation. 相似文献
687.
Lakshminarayana JS O'Neill HJ Jonnavithula SD Léger DA Milburn PH 《Environmental pollution (Barking, Essex : 1987)》1992,76(3):201-210
Preliminary results are reported from a co-operative study between Agriculture Canada and Environment Canada on environmental impacts of atrazine measured in a field stream receiving agricultural drainage. Systematically, tile drained plots of known crop rotation, area, flow and pesticides use were used in the study. A maximum tile drainage concentration of 13.9 microg liter(-1) atrazine was measured while the maximum measured stream concentration was 1.89 microg liter(-1). Phytoplankton and zooplankton samples were collected on a bi-monthly basis during the growing season. The study indicated possible negative impacts of low concentrations of atrazine on planktonic drift populations, when natural stream flow was reduced, resulting in a lower dilution capacity. A 20 m section of the stream was affected by the tile drainage waters as measured by the resident biological community. Both atrazine and ambient environmental conditions were felt to be contributing to the measured results. No negative impacts on planktonic drift populations were evident beyond 50 m downstream of the tile drainage and stream confluence. 相似文献
688.
Pfendler Stéphane Einhorn Olympe Karimi Battle Bousta Faisl Cailhol Didier Alaoui-Sosse Laurence Alaoui-Sosse Badr Aleya Lotfi 《Environmental science and pollution research international》2017,24(31):24611-24623
Environmental Science and Pollution Research - Ultra-violet C (UV-C) treatment is commonly used in sterilization processes in industry, laboratories, and hospitals, showing its efficacy against... 相似文献
689.
690.
Perillo Vanesa L. Bohn Vanesa Y. Menéndez María Clara Ronda Ana C. Vitale Alejandro J. Perillo Gerardo M. E. Piccolo M. Cintia Cuadrado Diana G. 《Environmental science and pollution research international》2022,29(11):15490-15500
Environmental Science and Pollution Research - Nutrient discharge into rivers and estuaries and the factors that control it need to be further understood to decrease the risk of harmful algae... 相似文献