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771.
Yinyin Su Binglu Zhao Wei Xiao Runping Han 《Environmental science and pollution research international》2013,20(8):5558-5568
An agricultural by-product, natural wheat straw (NWS), was soaked in 1 % cationic surfactant (hexadecylpyridinium bromide, CPB) solution for 24 h (at 293 K), and modified wheat straw (MWS) was obtained. Analysis of FTIR, XFR, and nitrogen element showed that CPB was adsorbed onto surface of NWS. Then, MWS was used as adsorbent for the removal of light green dye (LG, anionic dye) from aqueous solution. The experiment was performed in batch and column mode at room temperature (293 K). Sodium chloride (up to 0.1 mol/L) existed in solution was not favor of LG dye adsorption. The equilibrium data were better described by Langmuir isotherm, and adsorption capacity of q m from Langmuir model was 70.01?±?3.39 mg/g. In fixed-bed column adsorption mode, the effects of initial LG concentration (30, 50, 70 mg/L) and flow rate (6.5, 9.0, 14.5 mL/min) on adsorption were presented. Thomas and modified dose–response models were used to predict the breakthrough curves using nonlinear analysis method, and both models can fit the breakthrough curves. Theoretical and experimental breakthrough curves were drawn and compared. The results implied that MWS can be used as adsorbent material to remove LG from aqueous solution. 相似文献
772.
Contamination status of dioxins in sediment cores from the Three Gorges Dam area, China 总被引:1,自引:0,他引:1
Lei Chen Yonghong Bi Kongxian Zhu Zhengyu Hu Wei Zhao Bernhard Henkelmann Silke Bernhöft Cedrique Temoka Karl-Werner Schramm 《Environmental science and pollution research international》2013,20(6):4268-4277
In order to screen dioxin pollution in sediment of Three Gorges Dam (TGD) area, three sediment cores were obtained from two sites in 2010~2011; each core was divided into different samples with every 10 cm depth. Sediment dating determined by radiometry (137Cs, 210Pb) and concentrations of dioxins were analyzed by high-resolution gas chromatography/mass spectrometry. The results indicated: Sediment dating showed no significant difference among all the samples from the same core and the two locations (ANOVA, p?>?0.05). The total amount of polychlorinated dibenzo-p-dioxins (PCDD)/Fs in all sample ranged from 30.7 to 371 pg/g dry weight (d.w.), with the mean value of 66.2 pg/g d.w. PCDDs occupied 60.33~85.22 % of dioxins in each sample, and PCDFs contributed to a very small extend. There was no significant difference in the dioxin concentration between 2010 and 2011 and in the two locations (t test, p?>?0.05), but the vertical distribution of dioxins showed significant different in different depths. Toxic equivalent (TEQ) (WHO 2005, Humans) of samples ranged from 0.15 to 1.60 pg/g d.w.; the mean was 0.41 pg/g d.w. No significant difference was found in TEQ between 2010 and 2011(t test, p?>?0.05). It could be concluded that the distribution of dioxins showed the spatial heterogeneous which resulted from the strong mixing and sediment deposition characteristics. Dioxin concentration in sediment cores was low with very low environmental risk potential. Dioxins at the two sites had the same origin, and exogenous input was the main source. It is the first report on the dioxins concentrations in sediment cores in the TGD area. 相似文献
773.
Björn Scholz-Starke Richard Ottermanns Ursula Rings Tilman Floehr Henner Hollert Junli Hou Bo Li Ling Ling Wu Xingzhong Yuan Katrin Strauch Hu Wei Stefan Norra Andreas Holbach Bernhard Westrich Andreas Schäffer Martina Roß-Nickoll 《Environmental science and pollution research international》2013,20(10):7009-7026
The impounding of the Three Gorges Reservoir (TGR) at the Yangtze River caused large flooding of urban, industrial, and agricultural areas, and profound land use changes took place. Consequently, substantial amounts of organic and inorganic pollutants were released into the reservoir. Additionally, contaminants and nutrients are entering the reservoir by drift, drainage, and runoff from adjacent agricultural areas as well as from sewage of industry, aquacultures, and households. The main aim of the presented research project is a deeper understanding of the processes that determines the bioaccumulation and biomagnification of organic pollutants, i.e., mainly pesticides, in aquatic food webs under the newly developing conditions of the TGR. The project is part of the Yangtze-Hydro environmental program, financed by the German Ministry of Education and Science. In order to test combinations of environmental factors like nutrients and pollution, we use an integrated modeling approach to study the potential accumulation and biomagnification. We describe the integrative modeling approach and the consecutive adaption of the AQUATOX model, used as modeling framework for ecological risk assessment. As a starting point, pre-calibrated simulations were adapted to Yangtze-specific conditions (regionalization). Two exemplary food webs were developed by a thorough review of the pertinent literature. The first typical for the flowing conditions of the original Yangtze River and the Daning River near the city of Wushan, and the second for the stagnant reservoir characteristics of the aforementioned region that is marked by an intermediate between lake and large river communities of aquatic organisms. In close cooperation with German and Chinese partners of the Yangtze-Hydro Research Association, other site-specific parameters were estimated. The MINIBAT project contributed to the calibration of physicochemical and bathymetric parameters, and the TRANSMIC project delivered hydrodynamic models for water volume and flow velocity conditions. The research questions were firstly focused on the definition of scenarios that could depict representative situations regarding food webs, pollution, and flow conditions in the TGR. The food webs and the abiotic site conditions in the main study area near the city of Wushan that determine the environmental preconditions for the organisms were defined. In our conceptual approach, we used the pesticide propanil as a model substance. 相似文献
774.
Optimal control of soybean aphid in the presence of natural enemies and the implied value of their ecosystem services 总被引:1,自引:0,他引:1
By suppressing pest populations, natural enemies provide an important ecosystem service that maintains the stability of agricultural ecosystems systems and potentially mitigates producers' pest control costs. Integrating natural control services into decisions about pesticide-based control has the potential to significantly improve the economic efficiency of pesticide use, with socially desirable outcomes. Two gaps have hindered the incorporation of natural enemies into pest management decision rules: (1) insufficient knowledge of pest and predator population dynamics and (2) lack of a decision framework for the economic tradeoffs among pest control options. Using a new intra-seasonal, dynamic bioeconomic optimization model, this study assesses how predation by natural enemies contributes to profit-maximizing pest management strategies. The model is applied to the management of the invasive soybean aphid, the most significant serious insect threat to soybean production in North America. The resulting lower bound estimate of the value of natural pest control ecosystem services was estimated at $84 million for the states of Illinois, Indiana, Iowa, Michigan and Minnesota in 2005. 相似文献
775.
The Great Western Development Strategy (GWDS) is a long term national campaign aimed at boosting development of the western
area of China and narrowing the economic gap between the western and the eastern parts of China. The Strategic Environmental
Assessment (SEA) procedure was employed to assess the environmental challenges brought about by the western development plans.
These plans include five key developmental domains (KDDs): water resource exploitation and use, land utilization, energy generation,
tourism development, and ecological restoration and conservation. A combination of methods involving matrix assessment, incorporation
of expert judgment and trend analysis was employed to analyze and predict the environmental impacts upon eight selected environmental
indicators: water resource availability, soil erosion, soil salinization, forest destruction, land desertification, biological
diversity, water quality and air quality. Based on the overall results of the assessment, countermeasures for environmental
challenges that emerged were raised as key recommendations to ensure ecological security during the implementation of the
GWDS. This paper is intended to introduce a consensus-based process for evaluating the complex, long term pressures on the
ecological security of large areas, such as western China, that focuses on the use of combined methods applied at the strategic
level. 相似文献
776.
777.
成都市餐厨垃圾产量分析预测及监管体系建设研究 总被引:1,自引:0,他引:1
整理汇总了成都市中心城区及郊县餐厨垃圾产生和收运现状,对其产量作出预测;在此基础上提出适合成都市自身情况的餐厨垃圾监管体系构建设想。 相似文献
778.
779.
能源是现代社会发展的重要基础,其在社会经济发展中占有不可替代的地位。以四川省统计年鉴及相关数据资料为基础,参考美国能流图绘制了四川省2010年的能流图,并对四川省2005~2010年间的能源输入、输出、消耗,以及相应的污染物排放进行了分析,分析发现:近年来能源消费总量增长迅速,年均增长率达10.8%,能源对外依存度较高,尤其是石油。能源消耗结构有待进一步优化,传统化石能源所占比重偏高,2010年达77.18%。同时构建了能源-社会经济-环境复合系统能流分析指标,分析了2005~2010年四川省能源、经济、环境两两子系统及三者系统之间的协调度,结果显示:四川省能源-经济-环境系统协调度不断上升,2010年三者综合协调度0.97238。最后根据能流分析、污染物排放水平、协调度分析等结果,提出了四川省能源发展战略、能流的优化管理、节能减排等对策建议。 相似文献
780.
现代节庆活动发展迅速,有效塑造了城市旅游形象,促进了城市旅游业的发展。以苏州国际旅游节为例,对历届苏州国际旅游节进行了初步梳理和分析,利用相关数据,对其产生的旅游经济效应、社会文化效应和环境效应进行了综合评价,认为苏州国际旅游节成功塑造了苏州的城市形象,刺激了苏州旅游业发展,有利于苏州旅游资源的有效整合。当前苏州国际旅游节在运营模式、主题创新和当地居民参与度等方面还存在一些问题,对此进行了思考并提出改进建议,以期更好地发挥苏州国际旅游节的整体旅游效应。 相似文献