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671.
我国海滩垃圾污染现状及控制对策   总被引:2,自引:0,他引:2       下载免费PDF全文
为明晰我国各海域的海滩垃圾污染状况及垃圾主要来源,在我国各海区选择24个代表性采样点,共86个调查样方,对我国各海域的海滩垃圾的种类、来源进行了详细调查和重点区域的跟踪调查.结果表明:我国海滩垃圾平均个数为1.03 m-2,其中塑料类最多(占37.37%),其次为泡沫类(占35.67%);总密度为15.91 g/m2,塑料类密度(3.62 g/m2)最大,其次为织物(布)类(2.87 g/m2)和木制品类(1.97 g/m2);主要来源是生活垃圾和旅游垃圾,分别占垃圾总量的39.26%和25.23%;对照国际国内相关调查资料,我国海洋垃圾的污染呈逐渐恶化的趋势,总体形势不容乐观.针对我国海洋垃圾的污染控制,提出应通过进一步海洋垃圾污染调查工作,从制订污染防治监督管理办法、编制污染防治专项规划等方面入手理清各部门管理权责;同时以政府为主导,联合公众、企业、NGO(非政府组织)等多方力量,建立海洋垃圾回收资源化示范点,开展海洋垃圾宣传、清理和海滩清扫活动等控制对策.   相似文献   
672.
Changes in metal concentrations in the litter of Potamogeton crispus were monitored during a consecutive 40-day in situ decomposition experiment using the litterbag method.The accumulation index was calculated and used to indicate the changes in the metals in litter.The results showed that the concentrations of Al,Cd,Cr,Fe,Mn,and Pb in litter increased significantly during the decomposition,while Cu and Zn concentrations decreased dramatically.Significant positive correlations were found between the concentrations of Al,Cr,Fe,and Mn and between Cu and Zn.Moreover,Cu and Zn both negatively correlated with Al and Fe.The remaining dry mass was negatively correlated with Al and Fe concentrations but positively correlated with Cu and Zn concentrations.Generally the accumulation index values of metals other than Al were less than one,indicating that the litter of P.crispus acted as a source of metals to the surrounding water body.Al was the only metal that showed continuous net accumulation in litter.The net accumulation of Fe and Mn in litter during the last 10 days of the experiment may indicate the precipitation of Feand Mn-oxides.It was estimated that 160 g/m~2(dry weight)P.crispus was decomposed in40 days.This was equivalent to releasing the following amounts of metals:0.01 mg Cd,0.03 mg Cr,0.71 mg Cu,0.55 mg Mn,0.02 mg Pb and 13.8 mg Zn into surrounding water,and accumulating 149 mg Al and 11 mg Fe,in a 1 m~2 area.  相似文献   
673.
To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y_2O_3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421 L/(m~2·hr) under the trans-membrane pressure of 0.03 bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10 mg/L between pH 3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater.  相似文献   
674.
污染源产排污数据是一切环保工作的基础,确保真实可信具有十分重要的意义.为此,分析了影响污染源产排污数据质量的主要因素:受经济利益驱动的自身因素;受政绩利益驱动的管理因素和受地方保护驱动的政府因素等.在新环保法未得到充分贯彻,排污单位、环保主管部门和地方政府三者违法成本均低于守法成本的条件下,以博奕论为分析工具讨论了三种影响因素产生负面作用的必然性,并根据分析结果针对性地提出了提高数据质量的应对策略.  相似文献   
675.
"电能替代"是治理城市雾霾的重要途径探讨   总被引:1,自引:0,他引:1  
城市雾霾已经严重影响城市居民的正常生活与工作.研究表明,传统化石燃料在城市及其周边地区终端用户中直接使用是产生城市雾霾的主要原因.为了治理城市雾霾,国家和地方各级政府以及有关单位出台了一系列政策和行动方案.其中,利用绿色能源电能,在生产和生活中,代替传统化石能源,这一方案在城市终端用户中都可以大面积使用电能替代,是阻止城市雾霾的重要举措,电能替代不仅可以有效缓解城市雾霾,还可以提高城市智能化水平,是未来城市发展的重要趋势.  相似文献   
676.
The National Weather Service (NWS) forecasts floods at approximately 3,600 locations across the United States (U.S.). However, the river network, as defined by the 1:100,000 scale National Hydrography Dataset‐Plus (NHDPlus) dataset, consists of 2.7 million river segments. Through the National Flood Interoperability Experiment, a continental scale streamflow simulation and forecast system was implemented and continuously operated through the summer of 2015. This system leveraged the WRF‐Hydro framework, initialized on a 3‐km grid, the Routing Application for the Parallel Computation of Discharge river routing model, operating on the NHDPlus, and real‐time atmospheric forcing to continuously forecast streamflow. Although this system produced forecasts, this paper presents a study of the three‐month nowcast to demonstrate the capacity to seamlessly predict reach scale streamflow at the continental scale. In addition, this paper evaluates the impact of reservoirs, through a case study in Texas. Validation of the uncalibrated model using observed hourly streamflow at 5,701 U.S. Geological Survey gages shows 26% demonstrate PBias ≤ |25%|, 11% demonstrate Nash‐Sutcliffe Efficiency (NSE) ≥ 0.25, and 6% demonstrate both PBias ≤ |25%| and NSE ≥ 0.25. When evaluating the impact of reservoirs, the analysis shows when reservoirs are included, NSE ≥ 0.25 for 56% of the gages downstream while NSE ≥ 0.25 for 11% when they are not. The results presented here provide a benchmark for the evolving hydrology program within the NWS and supports their efforts to develop a reach scale flood forecasting system for the country.  相似文献   
677.
Environmental Science and Pollution Research - Atmospheric mercury monitoring is essential because of its potential human health and ecological impacts. Current automated monitoring systems include...  相似文献   
678.
Li  Man  Wu  JunJie  Deng  Xiangzheng 《Regional Environmental Change》2016,16(8):2429-2441
Regional Environmental Change - This paper estimates the impact of land use change on soil organic carbon (SOC) sequestration in China from 1985 to 2005 using a nationwide, georeferenced database...  相似文献   
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