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Effect of heavy metals (Cu, Pb, and As) on the ultrastructure of Sargassum pallidum in Daya Bay, China 总被引:1,自引:0,他引:1
Concentrations of Cu, Pb, and As were determined in seawater, surface sediment, Sargassum pallidum collected from the Daya Bay, China. The influence of metal contamination on the marine alga was investigated at chemical and ultrastructural level. Mean concentrations of Cu (19.44 mg kg?1) and Pb (33.99 mg kg?1) were found to be high in sediment, whereas concentration of As (122.29 mg kg?1) in S. pallidum was higher than that in water and sediment. The ultrastructure of S. pallidum cells was anomalous and aberrant. Energy-dispersive x-ray spectroscopic analysis revealed that the nanometal particles in the form of comparatively high-electron density substance diffused in the cell structures constituted by Cu, Pb, As, etc. There is a remarkable similarity or correspondence in the anomalous elements between the geochemistry and the botanic cell, and the heavy metals have potential hazardous effect on the ocean ecology system in Daya Bay. 相似文献
114.
Dynamics of the lakes in the middle and lower reaches of the Yangtze River basin, China, since late nineteenth century 总被引:1,自引:0,他引:1
Lijuan Cui Changjun Gao Xinsheng Zhao Qiongfang Ma Manyin Zhang Wei Li Hongtao Song Yifei Wang Shengnan Li Yan Zhang 《Environmental monitoring and assessment》2013,185(5):4005-4018
The middle and lower reaches of the Yangtze River basin have the most representative and largest concentration of freshwater lakes in China. However, the size and number of these lakes have changed considerably over the past century due to the natural and anthropogenic impact. The lakes, larger than 10 km2 in size, were chosen from relief maps and remotely sensed images in 1875, 1950, 1970, 1990, 2000, and 2008 to study the dynamics of lakes in the middle and lower reaches of the Yangtze River basin and to examine the causes and consequences of these changes. Results indicated that there was a dramatic reduction in lake areas, which decreased by 7,841.2 km2 (42.64 %) during the study period (1875–2008), and the number of lakes in this region changed moderately. Meanwhile, a large number of lakes in the middle and lower reaches of the Yangtze River basin were directly converted into paddy fields, ponds, building lands, or other land-use types over the study period. Therefore, all kinds of lake reclamation should be identified as the major driving factors for the loss of lake in this region. Furthermore, flooding, soil erosion, and sedimentation were also the main factors which triggered lake changes in different periods. Some wetland conservation and restoration projects have been implemented since the 1970s, but they have not reversed the lake degradation. These findings were of great importance to managers involved in making policy for the conservation of lake ecosystems and the utilization of lake resources. 相似文献
115.
The annual relative mass of storage organs cycle of Bufo gargarizans in southwestern China was studied from December 2005 to November 2006. We described how those organs changed in response to extreme temperatures. Energy reservation dropped to the lowest levels after dormancy for both sexes, and then increased for period of 4.25 month. However, the mass of these organs dropped again rapidly until August (liver) and September (fat bodies) due to the constraint from extreme high temperature occurred during the summer, and then non-significantly increased before hibernation. For ovaries, varied with a different profile to those of liver and fat bodies have a resting period of four months. In addition, the toads’ ovaries kept growing when the mass of liver and fat bodies declining accordingly during hibernation. Therefore, ovarian mass increased during the hibernation and non-hibernation period. 相似文献
116.
T酸一次洗水初步处理的研究 总被引:4,自引:0,他引:4
采用重氮化-偶合-混凝沉淀和重氮化-混凝沉淀两种方法对T酸一次洗水的初步处理进步了研究。T酸一次洗水经两种方法处理后,COD去除率分别为61.3%、50.5%,色度去除率分别为74.6%、71%。 相似文献
117.
Yan Song Robert Olshansky Yang Zhang Yu Xiao 《Journal of Environmental Planning and Management》2017,60(12):2192-2216
This article examines local recovery plans that were created in response to the Wenchuan earthquake and then suggests ways that planners can better apply the concept of sustainability to the recovery process. We utilize a plan evaluation protocol to analyze 16 recovery plans in counties and towns that were severely affected by the earthquake. We also conducted semi-structured interviews with public officials and planners, with the qualitative data gleaned from these interviews being used to supplement the plan quality assessment. The results reveal that local recovery plans do not appear to have incorporated sufficiently the concepts of sustainability. We conclude the paper with the following recommendations: emphasizing sustainability as a policy priority during vision and goal development; developing solid databases and planning techniques; designing a diversified set of regulatory- and incentive-based policy tools suitable for local governments; enhancing social and institutional learning; and further integrating multi-level and interagency governmental units. 相似文献
118.
Mubeen Ishrat Buekens Alfons Chen Zhiliang Lu Shengyong Yan Jianhua 《Environmental science and pollution research international》2017,24(23):19031-19043
Environmental Science and Pollution Research - Municipal solid waste incineration (MSWI) fly ash has been classified as hazardous waste and needs treatment in an environmentally safe manner.... 相似文献
119.
Xie Binghan Gong Weijia Ding An Yu Huarong Qu Fangshu Tang Xiaobin Yan Zhongsen Li Guibai Liang Heng 《Environmental science and pollution research international》2017,24(29):23226-23235
Environmental Science and Pollution Research - Microbial fuel cell (MFC) is a sustainable technology to treat cattle manure slurry (CMS) for converting chemical energy to bioelectricity. In this... 相似文献
120.
Hai-Long Zheng Wen-Jing Deng Yan Cheng Wei Guo 《Environmental geochemistry and health》2017,39(4):739-750
Fine particulate matter (PM2.5) levels, carbon dioxide (CO2) levels and particle-number concentrations (PNC) were monitored in train carriages on seven routes of the mass transit railway in Hong Kong between March and May 2014, using real-time monitoring instruments. The 8-h average PM2.5 levels in carriages on the seven routes ranged from 24.1 to 49.8 µg/m3, higher than levels in Finland and similar to those in New York, and in most cases exceeding the standard set by the World Health Organisation (25 µg/m3). The CO2 concentration ranged from 714 to 1801 ppm on four of the routes, generally exceeding indoor air quality guidelines (1000 ppm over 8 h) and reaching levels as high as those in Beijing. PNC ranged from 1506 to 11,570 particles/cm3, lower than readings in Sydney and higher than readings in Taipei. Correlation analysis indicated that the number of passengers in a given carriage did not affect the PM2.5 concentration or PNC in the carriage. However, a significant positive correlation (p < 0.001, R 2 = 0.834) was observed between passenger numbers and CO2 levels, with each passenger contributing approximately 7.7–9.8 ppm of CO2. The real-time measurements of PM2.5 and PNC varied considerably, rising when carriage doors opened on arrival at a station and when passengers inside the carriage were more active. This suggests that air pollutants outside the train and passenger movements may contribute to PM2.5 levels and PNC. Assessment of the risk associated with PM2.5 exposure revealed that children are most severely affected by PM2.5 pollution, followed in order by juveniles, adults and the elderly. In addition, females were found to be more vulnerable to PM2.5 pollution than males (p < 0.001), and different subway lines were associated with different levels of risk. 相似文献