生物柴油促进原油污染砂粒释放油

对4种生物柴油促进原油污染砂粒释放油的效果进行了研究,并探讨了菜籽生物柴油投加量和砂粒粒径对促进效果的影响。结果表明,菜籽生物柴油的促进效果最好,8 h释放量达到73%,废油脂生物柴油的效果最差,仅为52%;生物柴油的促进效果随着投加量的增大而升高,当投加量超过海水体积的5%时促进效果不再明显增加;在生物柴油作用下,小粒径砂粒上原油的释放效果优于大粒径砂粒。     

某矿区土壤和地下水重金属污染调查与评价

为了解湘南某矿区土壤和地下水重金属污染状况,对该矿区东河流域附近重金属污染源进行了调查,同时,对地下水和土壤样品进行了采样分析,结果表明：（1）该矿区东河流域附近的主要污染源有18个,其中有色金属选厂、尾矿库、采矿场和冶炼厂是排放重金属较多的污染源;（2）20个采样点中土壤重金属Pb、Cd、Zn、As和Hg大部分超过国家土壤环境质量标准（GB15618-1995）,综合污染指数P综〉1,该矿区主要的重金属污染元素为Cd、As和Hg,且土壤中Cd、Zn和As的含量两两之间存在着极显著的正线性相关关系;（3）重金属元素在土壤中的纵向迁移不明显,该矿区附近20个采样点的地下水并未受到污染,综合污染指数P综〈1。20个采样点地下水Pb、Cd、Zn、As、Hg浓度均能达到地下水质量标准（GB／T14848．9）中的Ⅲ类标准。     

实例分析卫生防护距离和大气环境防护距离设置条件

卫生防护距离、大气环境防护距离,其定义相近、设定途径相似,但两者又有不同。故在环境影响评价大气环境预测分析时对大气环境防护距离、卫生防护距离的概念极易混淆。本文以某县殡仪馆建设项目为例,详细分析建设项目设置防护距离的设置条件,帮助环评工作者理解防护距离设置原则,防止出现"在环境保护法规和导则要求下盲目划定、划大防护距离"的技术错误。     

山东半岛蓝色经济区海洋生态旅游发展研究

发展海洋生态旅游是实现山东半岛蓝色经济区战略的重要途径之一。在SWOT分析的基础上,指出在山东半岛蓝色经济区发展海洋生态旅游必须明确其动力机制,坚持统筹发展战略,从生态保护、社区参与、区域统筹和产业协同四个方面采取具体的对策。     

The Contribution of Marsh Zones to Water Quality in Dutch Shallow Lakes: A Modeling Study

Many lakes have experienced a transition from a clear into a turbid state without macrophyte growth due to eutrophication. There are several measures by which nitrogen (N) and phosphorus (P) concentrations in the surface water can be reduced. We used the shallow lake model PCLake to evaluate the effects of three measures (reducing external nutrient loading, increasing relative marsh area, and increasing exchange rate between open water and marsh) on water quality improvement. Furthermore, the contribution of different retention processes was calculated. Settling and burial contributed more to nutrient retention than denitrification. The model runs for a typical shallow lake in The Netherlands showed that after increasing relative marsh area to 50%, total phosphorous (TP) concentration in the surface water was lower than the Maximum Admissible Risk (MAR, a Dutch government water quality standard) level, in contrast to total nitrogen (TN) concentration. The MAR levels could also be achieved by reducing N and P load. However, reduction of nutrient concentrations to MAR levels did not result in a clear lake state with submerged vegetation. Only a combination of a more drastic reduction of the present nutrient loading, in combination with a relatively large marsh cover (approximately 50%) would lead to such a clear state. We therefore concluded that littoral marsh areas can make a small but significant contribution to lake recovery.     

Interactions between water and land in The Netherlands

The Netherlands are one of the most densely populated coastal countries in the world and there is only limited space for living, working, transport and recreation, while there is also the need to preserve and expand valuable natural habitats. In order to solve many existing and future conflicts of interest, and in order to create ‘added value’, strategies are developed to optimize the use of water-land systems. The principle of ‘building with nature’ is applied in order to integrate land in sea and water in land in such a way that future generations will be able to use coastal resources in a sustainable way, including a minimal effort to maintain the coastline and the promotion of a multiple-use system. The concept of Integrated multifunctional sustainable coastal zone development is introduced. This concept deals with a balanced approach to the lack of space for present and future coastal uses in relation to each other, to the hinterland, and to the sea. Flexible master plans are developed, taking into account many functions of the coastal zone, and facilitating adaptation to future developments—e.g. impacts of climate change and relative sea level rise. In this regard increasing the flexibility of the coastal zone is of vital importance. Large-scale coastal land reclamations in The Netherlands are dealt with, based on two different principles: (1) polder systems (low lying land reclamations surrounded and protected by dikes), (2) systems of ‘building with nature’—land reclamation protected by man-made foreshores, beaches and dunes. In the latter type new flexible dynamic-equilibrium coasts are created for many functions, while coastal vulnerability is reduced and a flexible coast is developed.     

干旱区土壤小麦根系界面Cd行为的环境影响研究——以甘肃省白银市区耕作灰钙土为例

通过大田环境-土壤-作物系统Cd行为的环境影响研究,初步发现,共存元素Cd、Cu、Ni、Pb、Zn对Cd元素在土壤-作物根系界面行为的影响表现为正效应,其影响顺序为Cd>Pb>Cu>Zn>Ni;pH值、粘粒、粗粉粒含量与根系Cd含量呈负相关;磷和砂粒含量与根系Cd含量呈正相关;细粉粒、粗粘粒、有机质和CEC     

江苏沿江某化工园区有机污染调查与研究

选择沿江某典型化工园区进行有机污染调查分析,分析污染排放特征及其对长江水质影响.为了解工业园区环境污染状况、从源头控制有机毒物等提供科学依据.     

三峡库区典型消落带冬季多环芳烃大气-植物/土壤交换过程与通量

三峡大坝每年周期性“蓄水-放水”,形成水位落差巨大的消落带,库区内污染物环境地球化学行为随之发生变化.以冬季淹没期消落带多环芳烃为研究对象,采集成对大气(n=16)、植物(n=12)和土壤样品(n=12),采用气相色谱/质谱法(GC/MS),分析USEPA 16PAHs浓度水平,解析来源,估算大气地表、大气-植物等多介质交换通量.结果表明:大气、土壤和植物中PAHs浓度为5.65～13.47ng/m³、70.86～13 5.44ng/g和78.23～1084.72ng/g,平均值分别为(8.58±2.78) ng/m³、(90.10±22.18) ng/g和(360.36±309.54) ng/g.大气中PAHs以2～3环为主(62.3%),植物中PAHs以3～4环为主(73.7%),土壤中PAHs以3环和5环为主(52.1%).特征分子比值法揭示煤、生物质燃烧是植物PAHs的主要来源,以石油为主的化石燃料燃烧是大气和土壤PAHs主要来源.“一室模型”表明,植物吸收PAHs的主要途径为植物-气相之间动态平衡限制下的气沉降.“逸度模型”表明,3...     

Integration of long-term fish kill data with ambient water quality monitoring data and application to water quality management

Almost half (354) of all fish kills (805) in South Carolina, USA, between 1978 and 1988 occurred in the coastal zone. These kills were analyzed for causative, spatial, and temporal associations as a distinct data set and as one integrated with ambient water quality monitoring data. Estuarine kills as a result of natural causes accounted for 42.8% followed by man-induced (35.1%) and undetermined causes (22.1%). Although general pesticide usage was responsible for 53.9% of man-induced kills, weed control activities around resorts and municipal areas accounted for slightly more kills (20.9%) than did agricultural (19.8%) or vector control (13.2%) uses. A dramatic decline in agricultural-related kills has been observed since 1986 as the integrated pest management approach was adopted by many farmers. When taken with the few kills (12.0%) resulting from wastewaters, this suggests that these two land-use activities have been successfully managed via existing programs (IPM and NPDES, respectively) to minimize their contributions to estuarine fish kills. Ambient trend monitoring data demonstrated no coastal-wide dispersion of pesticide pollution. These data confirmed the nature of fish kills to be site-specific, near-field events most closely associated with the contiguous land-use practices and intensities. Typically, fish kill data are considered as event-specific data limited to the bounds of that event only. Our analysis has shown, however, that a long-term data set, when integrated with ambient water quality data, can assist in regulatory and resource management decisions for both short- and long-term planning and protection applications.