贵阳市城市广场地表灰尘重金属水平及影响因素分析

以贵阳市9个广场为研究区域,采集地表灰尘并分析其As、Cd、Cu、Ni、Pb和Zn含量,同时记录广场周围环境的数据,探讨周围环境因素对地表灰尘重金属的影响.结果表明,贵阳市城市广场地表灰尘中As含量与贵州省土壤背景值相近,Cd、Cu、Ni、Pb和Zn的平均含量均高于相应元素的土壤背景值.广场土壤Pb含量与地表灰尘Pb含量具有显著正相关关系.非临水广场灰尘Cd、Cu和Pb含量均显著高于临水广场.城市广场地表灰尘重金属含量是受多种环境因素共同影响的结果.     

包头市公园及广场灰尘中重金属污染特征

本文以包头市具有代表性的26个公园和广场为研究对象,采集灰尘样品,利用X-Ray荧光光谱仪测定样品中Ba、Co、Cr、Cu、Mn、Ni、Pb、Zn和V的含量,采用修正的BCR提取法分析灰尘中各种重金属的存在形态,运用地累积指数法和污染负荷指数法,评价包头市公园和广场灰尘重金属的污染程度.研究结果显示,除了Mn、Ni和Zn以外,其他重金属元素的平均含量均高于其区域土壤背景值,尤其是Co、Cr和Pb,其平均含量为区域土壤背景值的2倍以上,富集明显.灰尘中各重金属元素的存在形态差异较大,其整体迁移能力由高到低为CoZnCuMnPbBaNiVCr,其中Co和Zn易迁移,危害较大.灰尘中各重金属元素地累积指数的平均值由大到小依次为CoCrPbCuBaVNiMnZn.包头市公园和广场灰尘受到不同程度的重金属污染,其中,包钢公园和包头乐园属于中度污染,而其他公园和广场属于偏中度污染.昆都仑区公园和广场灰尘重金属污染最严重.     

泰安市典型生态功能区空气负离子的时空分布及影响因素分析

为了探讨城市不同生态功能区空气负离子的时空分布及其影响因素,选取泰安市典型生态功能区(广场公园区、居民住宅区、城市道路区和工业厂房区),对其空气正、负离子浓度、可吸入颗粒物(PM10、PM2.5)浓度及其主要环境因子(空气温度、相对湿度、风速)进行同步监测,系统分析评价了各生态功能区空气负离子动态变化特征,以及与环境因子和可吸入颗粒物的相关性.结果表明:(1)广场公园区空气负离子浓度日变化呈明显的单峰形式,居民住宅区、城市道路区和工业厂房区呈双峰形式,广场公园区的空气负离子浓度最高,其次是居民住宅区和城市道路区,工业厂房区最低;(2)各生态功能区CI指数的平均值大小顺序依次为广场公园区居民住宅区城市道路区工业厂房区;(3)空气负离子日变化浓度趋势与相对湿度变化趋势相似,与温度、空气正离子、风速变化趋势相反.对空气负离子浓度日变化影响较大的环境因子是相对湿度和温度;(4)空气负离子和可吸入颗粒物(PM10、PM2.5)的日变化趋势相反,当空气负离子浓度增大时,可吸入颗粒物浓度减小,空气负离子和可吸入颗粒物呈显著负相关的关系,在相关性上PM10PM2.5.     

GIS在城市给水排水中的应用

阐述了GIS在城市给水排水领域的应用和发展趋势，包括水资源管理与分析、给水排水管网设计与管理、城市污水处理厂设计与管理、管网应急预警系统分析、水质污染状况和趋势分析等，并以大庆市给水排水管网信息管理系统实例，证明GIS可以及时准确完整的提供所需信息，更好的为市政管理者辅助决策提供依据。     

城市绿地空气负离子和PM_(2.5)浓度分布特征及其与微气候关系——以合肥天鹅湖为例

选取夏热冬冷地区合肥市天鹅湖3种不同类型绿地作为研究对象,并以空旷广场为对照,于2015年夏冬季分别测试了空气离子浓度、PM_(2.5)浓度、温度、湿度、风速等指标,分析了3种不同类型绿地以及对照广场的空气负离子浓度和PM_(2.5)浓度的时空特征,并进行了空气质量评价。结果表明,(1)实测样地的空气负离子浓度日变化较明显,呈现出上午高、下午低的趋势。同一时刻中对照广场空气负离子浓度最低,均低于3种不同类型绿地,峰值期间差异尤其明显。(2)夏冬季实测样地的空气负离子浓度由大到小依次为:疏林地、密林地、草地、对照广场。(3)实测样地的PM_(2.5)浓度日变化较明显,呈双峰双谷型,即早中晚低、白天高。(4)夏季实测样地PM_(2.5)浓度差异较显著,冬季不显著,且冬季PM_(2.5)浓度均大于夏季。(5)夏冬季实测样地的空气负离子平均浓度差异不大,CI指数接近,等级为D,空气清洁度属于容许范围;而对照广场的空气负离子平均浓度显著低于3种不同类型绿地,CI指数最低,等级为E级,空气清洁度属于中污染。由此得出以下结论:(1)合理的绿地空间布局能够提高空气负离子浓度,降低颗粒物污染并改善空气质量;(2)空气负离子浓度与PM_(2.5)浓度呈显著负相关;与相对湿度呈显著负相关,与风速呈显著正相关,与温度关系不明确。在此基础上进一步提出展望,建议对PM_(2.5)浓度和空气负离子浓度展开实时监测并对结果进行对比分析,找出两者之间的相关关系。同时对不同季节、不同天气状况、不同下垫面结构的城市绿地进行进一步深入研究,探索有利于居民身心健康和休闲运动的城市绿地类型。     

塔里木河干流农田排水资源化研究

近几十年经表明，农田排水对塔里木河干流水质盐化的影响不断加重。在塔里木河干流，农田排水资源化利用有如下几个有利条件：⑴农田排水有一定数量且渠网的延伸和改造难度不大；⑵荒漠可作为农田排水资源化利用的场所；⑶农田排水仍可勉强适于耐盐植物生长。根据区域不同利用农田排水拓展乔灌草防沙带、增加盐成土荒漠耐盐植被的盖度、使人工绿洲边缘的荒漠能够生长耐盐植物等都是农田排水资源化利用发展的方向。     

日本关于制浆造纸厂排水的生物影响研究现状

日本自１９９４年以来的近６年中，对全国近２０个制浆造纸厂排水进行了生物影响实验研究，研究内容主要是排水对生物急性毒性实验、亚急性毒性实验、慢性毒性实验与二恶英分析、采用食物链上不同等级的三类水生生物与发光菌等为实验生物、毒性指标主要有ＬＣ５０、ＩＣ２０、ＩＣ５０、ＥＣ１０、ＥＣ３０、ＬＯＥＣ、ＮＯＥＣ等，排水的ＣＯＤ／ＢＯＤ比值也与生物毒性具相关性。     

生态沟渠净化稻田排水动力学分析和生物相特征

本研究以太湖流域常见的菱角、水葫芦、梭鱼草、圆币草等水生植物和人工水草、塑料立体弹性填料为生态强化载体,构建"水生植物-载体生物膜-菌藻"复合型生态系统,研究了稻田排水中的氮、磷等营养元素的去除特性,构建氮、磷污染物的降解动力学模型,并调查了沟渠内"微生物-藻类"生物相特征.结果表明,生态沟渠运行期间,随着水稻进入不同的生长阶段,系统内氮、磷等营养元素的去除率都呈普遍下降趋势,总磷、氨氮、总氮、硝态氮平均去除率分别达到87.1%、92.3%、77.5%、88.6%,其中氨氮的去除率最高,化学需氧量(CODMn)的去除效果并不显著,各实验周期的污染物降解趋势均符合一级动力学降解模型.经生物相分析揭示:随着复合生态系统运行延续,系统内微生物、藻类的种类及Shannon-Weiner index等多样性指数呈不断增长趋势,表明复合生态系统水质改善后更适于多种类细菌与藻类生存与繁殖;复合生态系统中的菌、藻、水生植物及其表面附着的生物膜对污染物的去除具有协同作用,强化了生态沟渠的自净能力.     

暗管排水治理渍害田初探

暗管排渍改良低产稻田的试验结果表明,暗管排水显著降低地下水埋探,提高了土壤通透性,减少了土壤中的有毒物质,改善了水稻生长的土壤环境。在宾阳试区和环江试区采用不同水稻品种试验结果表明。与改良前的1989年相比,分别增产53.8％和36.5和36.5％;比同年农艺措施相同的明沟排水田分别增产11.15％和19.93％。     

页岩气开采水力压裂返排水中化学污染物的组成特征

伴随全球页岩气规模化开发,相关的区域环境问题引起了学界和公众的持续关注.页岩气开采与区域水资源息息相关,水力压裂不仅消耗大量水资源,而且产生返排废水,成分复杂,含数以千计的化学物质.因此,有关返排水中有机单体的相关研究越来越受关注.本文系统总结了近年来的相关文献和成果,重点论述了压裂返排水中有机污染物的来源、种类、浓度...     

塔里木河干流农田排水资源化研究

近几十年分析资料对比表明 ,农田排水对塔里木河干流水质盐化的影响不断加重。在塔里木河干流 ,农田排水资源化利用有如下几个有利条件 :( 1)农田排水有一定数量且渠网的延伸和改造难度不大 ;( 2 )荒漠可作为农田排水资源化利用的场所 ;( 3)农田排水仍可勉强适于耐盐植物生长。根据区域不同 ,利用农田排水拓展乔灌草防沙带、增加盐成土荒漠耐盐植被的盖度、使人工绿洲边缘的荒漠能够生长耐盐植物等都是农田排水资源化利用发展的方向     

稻麦轮作田氮素径流流失特征初步研究

针对近年来氮素化肥施用量大而利用率较低现状，在江苏太湖地区设计田间试验，研究稻麦轮作田全年氮素流失特征。结果表明，在本试验条件下稻季和麦季径流中氮损失量相近，麦季略高，约占施氮量的2％左右。麦稻轮作田径流氮损失中氨态氮较少，以硝态氮和其他形态氮为主，其中氨态氮损失以稻季为主，硝态氮损失稻季和麦季相近，其他形态氮损失麦季较多。不同作物田径流氮组成存在差异，麦季径流氮以硝态氮和其他形态氮为主，氨态氮极少，而稻季在施肥后短时间内径流氮中氨态氮、硝态氮和其他形态氮大致相当，其他时间以硝态氮和其他形态氮为主。     

Combined reticular blind drainage and vertical hierarchical drainage system for landfills located in areas with high rainfall and high groundwater level

A novel water control technology that combines the features of a reticular blind drainage system and a vertical hierarchical drainage system is developed and applied in the Yanziyan Sanitary Landfill, which is located at an area (Loudi City, Hunan Province, China) with high rainfall and high groundwater level. The reticular blind drain system, which was installed on the bottom and side walls of the landfill site, can conveniently guide the flow of groundwater out of the site while preventing a disorganized flow of groundwater. The vertical hierarchical drainage system was installed to separate rainfall water and leachate in the landfill site, thus efficiently reducing the pressure of leachate treatment. The whole drainage system plays a key role in foundation stabilization by seepage control and separation and in the instant drainage of rainfall water. The leachate reduction efficiency of the drainage technology was calculated in terms of leachate production before (336519 m³) and after (29664 m³) technology application. Over 90% of leachate derived from rainfall water and groundwater inflow was avoided upon installation of the vertical hierarchical drainage and reticular blind drainage systems. The technology can thus be popularized and applied for water control in landfills located in areas with high rainfall and high groundwater level. The proposed technology can be used to alleviate the pressure of leachate treatment and to reduce the risk of instability.     

利用矿化垃圾层预防和控制渗滤液导排系统堵塞

在卫生填埋场中,垃圾渗滤液导排系统堵塞普遍存在,悬浮固体形成的物理堵塞、有机物降解和金属离子沉淀导致的生物-化学堵塞是引起导排系统堵塞的关键因素.本文构建了"矿化垃圾+砾石层导排"的渗滤液下渗装置,通过矿化垃圾预处理渗滤液中悬浮固体和有机物以控制导排系统发生的物理和生物-化学堵塞.结果表明,在矿化垃圾层,渗滤液中化学需氧量(COD)和悬浮固体(SS)去除较多,去除率分别达到了85%和87%,并且Ca²⁺浓度也出现了波动较大的现象;然而,渗滤液在砾石层下渗过程中,其COD、SS和Ca²⁺浓度保持稳定.并且,砾石层可排水孔隙率在长期运行的过程中没有明显变化,表明渗滤液在砾石导排层没有形成明显的沉淀.与此同时,在没有添加矿化垃圾的对照组发现,砾石层可排水孔隙率减少最多的区段是渗滤液的进水点位(可排水孔隙率减少达到了53%),即渗滤液有机负荷最大处的饱和砾石层堵塞最为严重,其无机堵塞物主要是碳酸钙等.因此,在渗滤液流入砾石层前,采用矿化垃圾层部分饱和的方式对渗滤液中有机物和悬浮固体进行预处理,可以预防和控制渗滤液在砾石层形成沉淀堵塞.研究为填埋场的运行管理渗滤液导排系统堵塞提供了新的思路和方法.     

Toxic mine drainage from Asia’s biggest copper mine at Malanjkhand,India

This paper has studied the environmental deterioration due to copper mining in Malanjkhand at Central-east India. No data is available on environmental degradation at the studied site although geological aspects are well studied. Mine drainage from the mines is definitively toxic. The site is also undergoing various stages of acid mine drainage (AMD) particularly from the heap leaching sites and the tailing area. AMD impacted water steam and sediment were also analysed. Results show substantial level of contamination of almost all segments of environment. Presence of elevated level of other heavy metal viz. Au, Ag, Pb, Cr, Cd, Fe, Cu and base metals like Na, K in AMD impacted water and sediments is due to metal leaching effect of AMD. Bio monitoring with the help of benthic macro invertebrates and metal accumulation in plants was also carried to know the impact of the toxic drainage. Results prove a very significant impact on the environmental health.     

Effects of drainage water on plant diversity and distribution of agricultural drainage ditch beds in an arid irrigated area of Northwestern China

Agricultural drainage ditches are essential to sustaining food production in arid irrigation regions, with various sizes and drainage characteristics as important buffer ecotones in agricultural areas. Bed vegetation and water properties were investigated in 39 agricultural drainage ditches in the Lingwu District of Ningxia Yellow River Irrigation Area in Northwestern China. The results showed that water depth, width, and velocity generally increased with larger ditch size. Water salinity was higher in drainage ditches (>1?g/L) than in croplands, canals, and the Yellow River. Total nitrogen and total phosphorus were at high levels: ～1.6 and ～0.1?mg/L, respectively. Forty plant species belonging to 19 families and 31 genera were identified, with higher plant richness and diversity found in smaller sized drainage ditches. Macrophytes dominated the bed vegetation with a mean vegetative coverage of >30% in all-sized ditches, and Phragmites australis occurred with the most frequency. Water depth and salinity were considered as the primary factors affecting the distribution of vegetation in drainage ditch beds. The study suggests that practical conservation of smaller sized drainage ditches is conducive to increasing the plant diversity of agricultural landscapes.     

动态浸滤及几种静态预测法对云浮硫铁矿酸化特征及产酸潜力的比较

用几种静态预测方法研究了来自云浮硫铁矿矿石的产酸潜力,并结合动态浸滤试验方法对比了新旧矿石的氧化过程及产酸的动力学特征.静态预测结果表明:该矿矿石的净中和酸潜力NNP<-20、中和酸能力与产酸潜力比NP/AP<1:1、静产酸量NAG>10、NAG-pH<4,是强产酸矿.连续25周的动态浸滤试验研究表明:受碳酸盐控制,新矿浸滤液的pH值在7.46—6.45呈缓慢下降的趋势,25周内减小了近1个pH单位;旧矿已经产酸,浸滤液初期pH<4,10周内迅速下降到pH<3,体系氧化性及硫化物的氧化速率远远高于新矿,金属的释放大大增加.     

Loss of Pesticides from Agricultural Fields in SE Norway – Runoff Through Surface and Drainage Water

Loss of two pesticides with different mobility characteristics, bentazone (Koc 34) and propiconazole (Koc 1800), were studied at three agricultural fields (Askim, Bjørnebekk and Syverud) in SE Norway. A conservative tracer (Br) was used to follow the flow of water. The loss of pesticides varied among the fields, depending on hydrological characteristics and soil properties. The loss of pesticides was higher from two artificially levelled silty clay loam soils with poor aggregate stability (Askim and Bjørnebekk) compared to a loam/silt loam soil with increased content of organic carbon and better aggregate stability (Syverud). The total accumulated loss was <0.5% from all fields. The highest pesticide concentrations were measured at the first runoff episode after application for both the mobile (bentazone) and less mobile pesticide (propiconazole) in the surface runoff. In the drainage water, the peak for the less mobile pesticide coincided with the Br tracer, while the peak for mobile pesticide appeared earlier than the Br tracer. Rapid movement of water, particles and pesticides through soils indicate flow through macropores. Larger proportions (in percent of total applied) of both the mobile and the strongly sorbed pesticides were lost through the drainage as compared to the loss through surface runoff at Askim. Here, it is suggested that macropore flow contribute to the increased loss of pesticides through the drainage. At Syverud, high infiltration capacity reduces the amount of water available for surface runoff, and somewhat higher loss of the mobile pesticide was registered in the drainage compared to the surface runoff. For the strongly sorbed pesticide, however, propiconazole was neither detected in surface nor in drainage water at Syverud. Generally, there was a higher percentage loss of the mobile compared to the strongly sorbed pesticide in both surface and drainage water, which is in agreement with the pesticides mobility characteristics in soil. An exception was, however, the erodible soil Bjørnebekk, where a higher fraction of propiconazole was lost in the surface runoff compared to bentazone. Large amounts of sediment transport from the Bjørnebekk field probably contributed to enhanced transport of the strongly sorbed pesticide.     

排水对三江平原沼泽湿地土壤中化学元素的影响

以三江平原沼泽湿地生态试验站为研究基地 ,选择典型采样点 ,对排水沟土壤、沼泽土壤、沼泽化草甸土壤 (共有 6个采样点 ,2 8个样品 )进行测试 ,分析土样中主要离子 (HCO3- 、Cl- 、NO3- 、SO4 2 - 、Ca2 +、Mg2 +、K+、Na+)含量、重金属 (铁、锰、锌、铜 )含量、营养元素含量、有机质含量以及土壤pH值 ,研究沼泽排水对沼泽土壤中的化学元素含量的影响。研究结果表明 ,排水使沼泽土壤丧失大量的化学元素