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31.
32.
莱西地区施肥对地下水硝酸盐污染的过程 总被引:1,自引:0,他引:1
通过实地调查和渗水、硝化、吸附、弥散等室内外试验,获取了所需水文地质参数。利用VS2D/T(Variably Saturat-ed 2-D Flow and Transport Model)模型,建立了莱西地区包气带水流-溶质运移模型,分析了莱西地区施肥过程中对地下水的硝酸盐污染。研究结果表明,氮肥中的硝酸盐对地下水的补给量占当次施肥量的24%和43%,进入到地下水中硝酸盐的平均浓度分别约为130mg/L和177mg/L,远高于当地地下水中硝酸盐63.5mg/L的平均浓度,说明不合理的施用氮肥是造成莱西地区地下水硝酸盐污染的1个主要原因。通过模拟不同灌溉和施肥模式下对地下水的硝酸盐污染,得出灌溉方式的改变对于减少施肥造成的地下水硝酸盐污染的作用最大。 相似文献
33.
Mindhola River estuary, which receives industrial waste containing high concentrations of fluoride, and Purna River estuary, which is free from fluoride contamination, have been investigated. While fluoride behaved conservatively in Purna River estuary, significant deviation from the theoretical dilution line (TDL) in the chlorinity range 0·5–8‰ was observed in Mindhola River estuary due to the externally added fluoride which largely remained in solution. The excess of fluroide over the theoretically calculated value was at a maximum around a chlorinity of 3‰. High natural fluoride content of the river waters resulted in F/Cl ratios exceeding 300 × 10−5 at low chlorinities. The ratio decreased rapidly with increasing chlorinity and the value near to that of seawater was observed at chlorinities above 14‰. 相似文献
34.
沿海地区城市发展及地面沉降的系统控制 总被引:9,自引:0,他引:9
郑铣鑫 《海洋地质与第四纪地质》1992,12(1):57-65
本文运用系统工程原理,系统论述了地下水合理开发、管理和地面沉降系统控制,这对沿海地区地面沉降控制起到重要的作用。 相似文献
35.
Tommaso De Pippo Carlo Donadio Micla Pennetta Francesco Terlizzi Carlo Vecchione Margherita Vegliante 《Marine Ecology》2002,23(S1):154-168
Abstract. The interaction of coastal and submarine morphology with the hydrodynamic regimes exerts a control on coastal dynamic processes, conditioning the dispersion of sediments and potential pollutants existing in the area. Thus, the study of such parameters is useful in order to define environmental threats. Within the submerged sector of the Bagnoli coast and particularly in the southern part of the investigated area, there are sediment groups composed of very fine sands located in low-energy zones due to wave refraction and diffraction; they can also be found on the sea bottom and on the man-made structures typical of this zone. These areas show high pollutant levels of N, P, Cu, Fe, Mn, Ni, Pb, Zn, Cd, polyaromatic hydrocarbons (PAHs) and polychlorinated bi-phenyls (PCBs). The northern area, a place of high-energy hydrodynamic processes, also shows high concentration levels of pollutants due to the presence of secondary cell circulation.
Morphological research and analysis of textural characteristics of bottom sediments along the Bagnoli coast allowed the actual processes and their evolution in space and time to be defined. It has also been possible to correlate such processes to the seabed morphology system, the wave formations which affect the coast, the complex system of sediment transport, as well as to the man-made interventions in the area. The results of recent chemical analyses of beach sediments and bottom sediments off the Bagnoli coast were also incorporated. They prove the presence of heavy metals, PAHs and PCBs in high and sometimes very high concentrations. Finally, based on the results of research and analyses, a hypothesis for an intervention for environmental restoration has been formulated in order to renaturalise the coast through dredging and treatment of the sand, both on the seabed and on the emerged beach. 相似文献
Morphological research and analysis of textural characteristics of bottom sediments along the Bagnoli coast allowed the actual processes and their evolution in space and time to be defined. It has also been possible to correlate such processes to the seabed morphology system, the wave formations which affect the coast, the complex system of sediment transport, as well as to the man-made interventions in the area. The results of recent chemical analyses of beach sediments and bottom sediments off the Bagnoli coast were also incorporated. They prove the presence of heavy metals, PAHs and PCBs in high and sometimes very high concentrations. Finally, based on the results of research and analyses, a hypothesis for an intervention for environmental restoration has been formulated in order to renaturalise the coast through dredging and treatment of the sand, both on the seabed and on the emerged beach. 相似文献
36.
青岛市大气污染时间序列分析预报方法研究 总被引:5,自引:0,他引:5
根据青岛市大气污染监测资料 ,采用时间序列分析方法 ,建立多种预报模型 ,有原序列周期外延法、均生函数周期外延法、均生函数逐步回归法以及自回归预报法等 ,最后提出一种综合预报模型。连续预报试验表明 ,综合预报模型优于任何个别预报模型 ,有较好的预报能力。利用马尔可夫概型对污染状态 (轻、中、重 )进行了分级预报试验 ,也获得良好的效果。 相似文献
37.
近岸溢油漂移扩散预测方法研究——以胶州湾溢油事件为例 总被引:1,自引:0,他引:1
近些年,由于中国经济的高速发展,原油需求逐年增长,同时海上溢油事故发生的风险也在加剧。海上溢油会严重破坏海洋环境,危害我国经济发展,加强溢油漂移扩散预报研究能够为海上溢油应急响应提供技术支撑。因此,国家海洋信息中心研发了海上突发事件应急一体化预测预警系统。该系统基于GIS平台研发,能够在二维电子海图基础上叠加相关的海洋环境动力要素信息,模拟溢油扩散和漂移态势,同时计算剩余油量,估算溢油面积以及岸线吸附程度等。2013年11月22日,山东黄岛发生输油管道爆炸事故,造成大量原油溢入胶州湾。本文利用该系统结合高分辨率大气模型WRF的三重嵌套技术和海流模型SELFE的非结构化网格加密技术,对事故溢油漂移扩散开展了预测工作。预测结果显示,油污受胶州湾内往复流的影响极大,72 h后,胶州湾内外大部分海域都将存在油污,主要集中在黄岛沿岸海域、团岛及浮山湾附近,预测扫海面积为70.32 km2。经海事部门高分辨率卫星观测结果印证,系统模拟的溢油分布较为合理。该系统的业务化应用为相关海上溢油污染应急工作提供了一定理论依据和参考。 相似文献
38.
39.
在采用回收法治理锯条厂氰化物污水中,通过改造生产工艺,减少污水量,提高氰化物浓度及污水经除油后减压蒸馏,可回收50%~90%的氰化铂,其他盐分也可全部回收,从污水中蒸出的蒸馏水能在系统内循环使用。 相似文献
40.
A strain of yeast, which can endure high osmotic pressure, is employed for the sensitive material of the microbial BOD sensor. Two immobilization methods are used, I.e. Calcium alginate gel be ads and PV A gel beads. The results show that the PVA gel beads is better. The influences of osmosis and heavy metal ions on the yeast entrapped in the PVA gel beads are also studied in the experiment. 相似文献