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71.
The analytical results of 53 manure samples determined by wet digestion and dry ashing procedures were compared in order to evaluate their relative suitability for recovering different nutrient elements in manure and manure compost. Wet digestion recovered greater amounts of phosphorus (P), potassium (K), calcium (Ca), manganese (Mn), and zinc (Zn) in more samples than dry ashing. Nutrient contents in the samples were highly variable, with coefficients of variation (CV) ranging from 38% for magnesium (Mg) to 161% for copper (Cu) analyzed by the wet digestion procedure, and from 47% to 138% for Mg and Cu analyzed by the dry ashing procedure. The mean values of P, K, Ca, Mn, and Zn averaged for the 53 samples were significantly higher using wet digestion than dry ashing procedure, but both procedures recovered comparable amounts of iorn (Fe), Mg, and Cu. Correlations analysis between both procedures for each element showed reasonable to fair agreements for Ca (R 2?=?0.93), K (R 2?=?0.93), P (R 2?=?0.90), Mg (R 2?=?0.84), Fe (R 2?=?0.87), Mn (R 2?=?0.73), and Cu (R 2?=?0.66), but poor agreement for Zn (R 2?=?0.44). The low agreement between procedures for Zn suggests that wet digestion, which gave a higher recovery, should be a preferred procedure for analyzing Zn in manures.  相似文献   
72.
A growing awareness of increasing trends in coastal erosion and flooding due to climate change is triggering a demand for the rapid assessment of the potential responses of the coastlines around the world, principally in locations where human occupation is especially endangered. Investigations of present and future physical vulnerability and associated social risk have, therefore, become crucial for coastal management. In order to provide a quick and simple methodology for the identification of vulnerable coastal segments, Sharples (2006) has proposed a mapping methodology, called the smartline approach, which consists of representing, by means of simple lines, a geomorphic classification of the hinterland, backshore and beaches. The aim of this paper is to apply the smartline approach to coastal vulnerability assessment with inclusion of social data. The results show that this methodology is appropriate for the indication of coastal segments with varying degrees of vulnerability to erosion and flooding and for the appraisal of the resulting social risk.  相似文献   
73.
In developing Asian countries, the municipal cooperations are unable to handle the increasing amount of municipal solid waste, which into the uncollected waste being spread on roads and in other public areas leading to tremendous pollution and destruction of land and negative impact on human health. Generation of municipal solid waste increases with the rapid urbanization and accelerated economic development with in the rapidly growing advanced technological societies. The nature of municipal solid waste is a term usually applied to a heterogeneous collection group of waste produced in urban areas, the nature of which varies from region to region. The common problem faced by all developing Asian countries, is the disposal of municipal solid waste and availability of land fill site area. Present study explains the correlation analysis of among different factors of municipal solid waste and the objective is to assess the future municipal solid waste stream in Asian developing countries. The other goal of this study was to calculate the future land area that would be required for landfill site disposal in Asian developing countries.  相似文献   
74.
The extensive use of pesticides represents a risk to human health and to the environment. This study aimed to investigate if the exposure to atrazine and diuron, two herbicides widely used in Brazil, could induce changes in the susceptibility profile to aztreonam, colistin and polymyxin B antimicrobials in isolates of P. aeruginosa obtained from soil samples by using the determination of minimum inhibitory concentration (MIC) test. Three isolates had an increase of MIC to aztreonam after exposure to both herbicides and one isolate did not show any MIC change. The MexAB-OprM efflux pump has already been upregulated in these isolates and the herbicides atrazine and diuron did not increase MexAB-OprM overexpression. Therefore, the decrease in aztreonam susceptibility was not directly related to this pump, suggesting that probably other mechanisms should be involved.  相似文献   
75.
In the complex causation behind land change, dependent causation can play a central role. A case in point concerns land tenure diversity, where contrasting use rules for different lands may affect the impacts of other drivers on land use outcomes. We therefore evaluate the evolutionary theory of land rights (ETLR), which assumes homogeneous private property rights, in order to test for dependent causation due to distinct use rules among various types of private lands. In the present analysis, we focus on whether land tenure type modifies the effects of highway infrastructure on key outcomes highlighted in the ETLR framework. We take up the case of rural settlements along the Inter-Oceanic Highway in the eastern part of the Brazilian state of Acre, where there is considerable land tenure diversity. Findings from multivariate models for land titling, the castanha nut harvest, and cattle pasture all indicate that the effects of infrastructure depend on land tenure type. These results confirm the importance of dependent causation behind land use and bear implications for theory on land change, infrastructure impacts, and land system science.  相似文献   
76.
The synthesis of recycled plastics from recovered monomeric materials obtained from the depolymerization reaction of fiber-reinforced plastics (FRP) was examined. The depolymerization reaction of FRP in the presence of N,N-dimethylaminopyridine (DMAP) smoothly yielded the corresponding monomers, which mainly consisted of dimethyl phthalates. The polymerization reaction with this monomer failed to form the corresponding unsaturated polyesters due to contamination by N-methyl-4-pyridone, a decomposition product of DMAP. An efficient purification of the recovered monomer was achieved by washing with water, and the purified monomer successfully yielded the corresponding polymers. A hardness test revealed that the polymers were as hard as the polyester made from virgin materials. The present modification provides a practical method for the preparation of recycled plastics from depolymerized plastics.  相似文献   
77.
The extension of pollutant accumulation in plant leaves associated with its genotoxicity is a common approach to predict the quality of outdoor environments. However, this approach has not been used to evaluate the environmental quality of outdoor smoking areas. This study aims to evaluate the effects of environmental tobacco smoke (ETS) by assessing particulate matter 2.5 μm (PM2.5) levels, the pollen abortion assay, and trace elements accumulated in plant leaves in an outdoor smoking area of a hospital. For this, PM2.5 was measured by active monitoring with a real time aerosol monitor for 10 days. Eugenia uniflora trees were used for pollen abortion and accumulated element assays. Accumulated elements were also assessed in Tradescantia pallida leaves. The median concentration of PM2.5 in the smoking area in all days of monitoring was 66 versus 34 μg/m3 in the control area (P?<?0.001). In addition, the elements Al, Cd, Cu, Ni, Pb, Rb, Sb, Se, and V in Tradescantia pallida and Al, Ba, Cr, Cu, Fe, Mg, Pb, and Zn in Eugenia uniflora were in higher concentration in the smoking area when compared to control area. Smoking area also showed higher rate of aborted grains (26.1?±?10.7 %) compared with control (17.6?±?4.5 %) (P?=?0.003). Under the study conditions, vegetal biomonitoring proved to be an effective tool for assessing ETS exposure in outdoor areas. Therefore, vegetal biomonitoring of ETS could be a complement to conventional analyses and also proved to be a cheap and easy-handling tool to assess the risk of ETS exposure in outdoor areas.  相似文献   
78.
In order to better understand the behavior of 210Pb deposition in Far East Asia, comprehensive data of monthly 210Pb deposition, which includes several time-series and spatial distribution data at 14 stations in Japan and 2 stations in Taiwan, were analyzed. Pb-210 deposition at most of the sites exhibited a typical seasonal change with higher values in winter and lower values in summer; especially, the greatest 210Pb deposition in the world occurred in winter at sites beside the Japan Sea. The deposition behavior of 210Pb in Far East Asia differed between winter and summer. The meteorological phenomenon peculiar to winter of the Japan Sea side, i.e., formation of the Japan Sea convergence zone, might cause the high 210Pb concentration in rainwater, as may heavy snowfall. The 210Pb concentration in rainwater showed long-term variability, although this differed between winter and summer. This long-term variability may be related to climatological factors such as El Niño.  相似文献   
79.
The environmental pollution associated with mining and metallurgical activities reaches its greatest extent in several Andean cities and villages. Many locations in this area have accumulated through centuries a large amount of mining wastes, often disregarding the magnitude of this situation. However, in these naturally mineralized regions, there is little information available stating the exact role of mining and metallurgical industries in urban pollution. In this study, we demonstrated that the various metallic elements present in indoor dust (As, Cd, Cu, Pb, Sb, Sn, Zn) had a common origin and this contamination was increased by the proximity to the mines. Lead dust concentration was found at concerning levels for public health. In addition, wrong behaviors such as carrying mining workwear home contributed to this indoor dust pollution. Consequently, the constant exposure of the population could represent a potential health hazard for vulnerable groups, especially children.  相似文献   
80.
The hydrothermal treatments were conducted prior to the carbonization of oak woods and the obtained charcoals were activated using carbon dioxide or water vapor. The hydrothermal treatments brought about the elutions of acid-soluble lignin fractions as well as hemicellulose fractions accompanied with the decomposition of lignin carbohydrate complexes in the cell walls, which lowered not only the carbon yield of charcoal but also the crystal parameters for the carbon crystallites. However, the activated carbons (AC) produced via the hydrothermal pre-treatment showed superior adsorption properties especially for the adsorptions of 2-methylisoborneol and geosmin as compared with the untreated commercial AC. The hydrothermal treatments prior to the carbonization have some potential to increase the fractions of meso-pores effective for the adsorption of globular shaped molecules.  相似文献   
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