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61.
Loghman Khoda Krami Fazel Amiri Alireza Sefiyanian Abdul Rashid B. Mohamed Shariff Tayebeh Tabatabaie Biswajeet Pradhan 《Environmental monitoring and assessment》2013,185(12):9871-9888
One hundred and thirty composite soil samples were collected from Hamedan county, Iran to characterize the spatial distribution and trace the sources of heavy metals including As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn, and Fe. The multivariate gap statistical analysis was used; for interrelation of spatial patterns of pollution, the disjunctive kriging and geoenrichment factor (EFG) techniques were applied. Heavy metals and soil properties were grouped using agglomerative hierarchical clustering and gap statistic. Principal component analysis was used for identification of the source of metals in a set of data. Geostatistics was used for the geospatial data processing. Based on the comparison between the original data and background values of the ten metals, the disjunctive kriging and EFG techniques were used to quantify their geospatial patterns and assess the contamination levels of the heavy metals. The spatial distribution map combined with the statistical analysis showed that the main source of Cr, Co, Ni, Zn, Pb, and V in group A land use (agriculture, rocky, and urban) was geogenic; the origin of As, Cd, and Cu was industrial and agricultural activities (anthropogenic sources). In group B land use (rangeland and orchards), the origin of metals (Cr, Co, Ni, Zn, and V) was mainly controlled by natural factors and As, Cd, Cu, and Pb had been added by organic factors. In group C land use (water), the origin of most heavy metals is natural without anthropogenic sources. The Cd and As pollution was relatively more serious in different land use. The EFG technique used confirmed the anthropogenic influence of heavy metal pollution. All metals showed concentrations substantially higher than their background values, suggesting anthropogenic pollution. 相似文献
62.
Heba Elbasiouny Mohamed Abowaly Abd_Allah Gad Adel Abu_Alkheir Fathy Elbehiry 《Journal of Coastal Conservation》2017,21(1):105-114
Most of coastal area in Nile Delta, Egypt, is salt-affected soils and have low carbon (C) and nitrogen (N) inputs as a result of declining vegetation growth and low net primary production. Therefore, this study amid to compare between C and N pools in degraded (uncultivated and salt-affected soil) and restored (cultivated and reclaimed 20 years ago) locations in North Nile Delta. and to examine the impact of cultivation on sequestering C and N pools in this area as one of the most important methods for mitigating climate change impacts. C and N pools increased significantly in surface soil from 2.99 and 0.43 Mgh?1 in uncultivated sites to 19.26 and 1.66 Mgh?1 in cultivated ones as salinity was reduced and net primary production was increased due to leaching and reclamation. Particulate (associated with sand) and nonparticulate (associated with clay +silt) soil organic C or N was significantly higher cultivated sites. In addition, nonparticulate organic C or N was lower than particulate part indicating and supporting the strong relationship between organic matter and clay. The sequestration rate (in approximately 1 m profile) was 1.69 and 0.14 Mgh?1 yr.?1 C and N pools respectively. Although the cultivation is leading to loss of organic matter in some areas; C and N in this coastal area are partially restored and stored. Therefore, restoration and appropriate management practices will lead to mitigate the negative impacts of climate change in this area. 相似文献
63.
Fish live in direct contact with their immediate external environment and, therefore, are highly vulnerable to aquatic pollutants. In this study, Oreochromis niloticus were caught at three different sites in Al-Hassa irrigation channels, namely Al-Jawhariya, Um-Sabah and Al-Khadoud. The histological changes in gills and liver were detected microscopically and evaluated with semi-quantitative analyses. Also, heavy metals have been determined in the water samples in these sites. Results showed that all sites were polluted by different kinds of heavy metals. Cd and Pb were mostly detected at concentrations above the WHO reference values. Meanwhile, various histopathological abnormalities were observed in gills and liver of fish specimens. In the gill filaments, cell proliferation, lamellar cell hyperplasia, lamellar fusion, lifting of the respiratory epithelium, and the presence of aneurysmal areas were observed. In the liver, there was vacuolization of the hepatocytes, sinusoidal congestion, necrosis of the parenchyma tissue, nuclear pyknosis, eosinophilic hepatocellular degeneration, pigment accumulation, an increase in the number and size of melanomacrophage centers. Liver tumors with severe chronic inflammation were occasionally found in fish at Al-Khadoud area (first-time report). The histological lesions were comparatively most severe in the liver. Despite heavy metals assessment did not show marked differences among sites, histopathological biomarkers indicated that the surveyed fish are living under stressful environmental conditions. So, we suggest use those biomarkers in future monitoring of aquatic systems. 相似文献
64.
Mohamed Osman Saeed Mohd Nasir Hassan M. Abdul Mujeebu 《Waste management (New York, N.Y.)》2009,29(7):2209-2213
This paper presents a forecasting study of municipal solid waste generation (MSWG) rate and potential of its recyclable components in Kuala Lumpur (KL), the capital city of Malaysia. The generation rates and composition of solid wastes of various classes such as street cleansing, landscape and garden, industrial and constructional, institutional, residential and commercial are analyzed. The past and present trends are studied and extrapolated for the coming years using Microsoft office 2003 Excel spreadsheet assuming a linear behavior. The study shows that increased solid waste generation of KL is alarming. For instance, the amount of daily residential SWG is found to be about 1.62 kg/capita; with the national average at 0.8–0.9 kg/capita and is expected to be increasing linearly, reaching to 2.23 kg/capita by 2024. This figure seems reasonable for an urban developing area like KL city. It is also found that, food (organic) waste is the major recyclable component followed by mix paper and mix plastics. Along with estimated population growth and their business activities, it has been observed that the city is still lacking in terms of efficient waste treatment technology, sufficient fund, public awareness, maintaining the established norms of industrial waste treatment etc. Hence it is recommended that the concerned authority (DBKL) shall view this issue seriously. 相似文献
65.
Residues of PCDDs/F, non-ortho, mono-ortho PCBs, and other PCBs were monitored in the tissues of mullet fish, bolti fish, bivalves and crab taken from Lake Temsah, at Ismailia, Egypt. Results showed that 2,3,7,8 Tetra CDD and 1,2,3,7,8 Penta CDD were the most frequently detected PCDD congeners. Similarly, 2,3,7,8 Tetra CDF, 1,2,3,7,8 Penta CDF and 2,3,4,7,8 Penta CDF were the most frequently detected PCDF congeners. No relationship was apparent between the concentrations of detected PCDDs congeners and the degree of chlorination, except with crab samples in which an increase in the chlorination coincided with a decrease in the concentrations of the congeners. In PCDF congeners, detected residues have had a reversed relationship with chlorination increase. In PCDD congeners, Octa CDD had the highest detected concentrations in the two fish species, while in the bivalves and crab, 2,3,7,8 Tetra CDD had the highest concentrations. The mullet fish had the highest total PCDDs concentration, at 0.398?pg/g fresh weight, followed by crab at 0.395?pg/g fresh weight, then bivalves and bolti fish at 0.187 and 0.062?pg/g fresh weight, respectively. In all the examined organisms, the total concentrations of PCDFs were much higher than the total concentrations of the PCDD congeners. The WHO–TEQ values were 11.92, 39.12, 25, and 3.6?pg/g fresh weight, for mullet fish, bolti fish, bivlaves and crab, respectively. The concentration of the mono-ortho congeners CB 118 was the highest detected of all non-ortho and mono-ortho PCBs congeners, with values of 0.382, 0.022, 0.231 and 0.357?ng/g fresh weight, in mullet fish, bolti fish, bivalves and crab, respectively. The WHO–TEQ concentrations were 0.799, 0.003?pg/g fw, 0.05?pg/g fresh weight, 0.676?pg/g, and 0.799?pg/g fresh weight, for the same species, respectively. The total concentration of PCBs 28, 52, 95, 99, 101, 105, 110, 118, 138, 146, 149, 151, 153, 170, 177, 180, 187 were 6.86?ng/g fresh weight for mullet fish, 0.2?ng/g fresh weight, for bolti fish, 2.72?ng/g fresh weight for bivalves and 2.8?ng/g fresh weight for crab, respectively. 相似文献
66.
Ahmad Tasneem Nazar Sonaina Ahmad Kafeel Khan Zafar Iqbal Bashir Humayun Ashfaq Asma Munir Mudasra Munir Zunaira Hussain Khadim Alkahtani Jawaher Elshikh Mohamed Soliman Nadeem Muhammad Malik Ifra Saleem 《Environmental science and pollution research international》2021,28(23):29110-29116
Environmental Science and Pollution Research - The instant endeavor was undertaken to monitor copper (Cu) contents in water, soil, forage, and cow’s blood impacted by heavy automobiles in... 相似文献
67.
Schomberg HH Gaskin JW Harris K Das KC Novak JM Busscher WJ Watts DW Woodroof RH Lima IM Ahmedna M Rehrah D Xing B 《Journal of environmental quality》2012,41(4):1087-1095
Interest in the use of biochar from pyrolysis of biomass to sequester C and improve soil productivity has increased; however, variability in physical and chemical characteristics raises concerns about effects on soil processes. Of particular concern is the effect of biochar on soil N dynamics. The effect of biochar on N dynamics was evaluated in a Norfolk loamy sand with and without NHNO. High-temperature (HT) (≥500°C) and low-temperature (LT) (≤400°C) biochars from peanut hull ( L.), pecan shell ( Wangenh. K. Koch), poultry litter (), and switchgrass ( L.) and a fast pyrolysis hardwood biochar (450-600°C) were evaluated. Changes in inorganic, mineralizable, resistant, and recalcitrant N fractions were determined after a 127-d incubation that included four leaching events. After 127 d, little evidence of increased inorganic N retention was found for any biochar treatments. The mineralizable N fraction did not increase, indicating that biochar addition did not stimulate microbial biomass. Decreases in the resistant N fraction were associated with the high pH and high ash biochars. Unidentified losses of N were observed with HT pecan shell, HT peanut hull, and HT and LT poultry litter biochars that had high pH and ash contents. Volatilization of N as NH in the presence of these biochars was confirmed in a separate short-term laboratory experiment. The observed responses to different biochars illustrate the need to characterize biochar quality and match it to soil type and land use. 相似文献
68.
69.
A high-performance liquid chromatography with photodiode array detector analytical method was developed to determine the residue levels of flusilazole in grape and investigate the dissipation pattern and safety. The results showed that the mean recoveries were in the range of 86%–90%. Limits of detection and quantification were 0.008 and 0.02 mg/kg, respectively. The residue levels of flusilazole were best described by first-order rate kinetics and with half-lives ranging from 4.2 days (recommended dose) to 4.6 days (double the recommended dose). In conclusion, flusilazole at the recommended or even at double the recommended doses does not pose any apparent hazards to consumers. 相似文献
70.
The general public, government regulators, and environmental organizations are increasingly demanding industries to reduce their environmental impacts and report progress. This in turn resulted in numerous requirements for reporting environmental data. Environmental assessments are a useful tool in gathering and documenting this data. The assessments also assist decision makers to quantify impacts of their activities and plan for appropriate mitigation measures. There are different types of environmental assessments, each having specific purpose(s) and addressing specific audience(s). This paper gives an overview of common environmental concerns associated with oil and gas industry and shares insights on types of environmental assessments that are widely used. It discusses general methodologies to define the scope, approach, measurement standards, and reporting. Potential challenges encountered in conducting these assessments in an international arena and under a wide variety of regulatory requirements are addressed. Practical approach in execution of these assessments is described here, and strategy in dealing with the challenges is presented. 相似文献