利用地质雷达圈定浅部地层     

Domi.  DF 吕珍 《地震科技情报》1996,(8):34-40

为了调查浅部地层和确定雷达技术性能及其适用性，我们在四个测点上进行了地质雷达测量。所有测量均使用一套基本模拟记录系统和８０ＭＨｚ的单一天线，所有测点都有较好的地层控制，以利于评价雷达的效果，四个测点的介质成分和范围都有明显差别，在俄州西南部冰冻区的高地农场上的测点，富含粘土的土壤覆盖了较浅的基岩，雷达剖面上的一些土壤层位能够辨认出来，但仅到１．４ｍ深，在俄西南部的砂砾采石场上绘制出超过４ｍ深的不饱  相似文献   

Sadlermiut mystery     

Pelly DF 《Canadian geographic》1987,107(5):28-32

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地下水中砷元素的形成及其控制因素   总被引：3，自引：0，他引：3  

曾昭华  张志良 《上海国土资源》2003,(3):11-15

研究了长江中下游地区和吉林省地区地下水中砷元素形成和主要控制因素及其分布规律。结果表明,地下水中砷主要以H_3ASO_3、H_2AsO_4~-、HA_3O_4~(2-)等形式存在。它的形成和分布与含水介质及其上覆土层的砷含量、地下水的酸碱度、地下水的迳流条件、氧化还原环境、有机物质及铁锰等有密切的关系。  相似文献   

Impact of sampling depth and plant species on local environmental conditions, microbiological parameters and bacterial composition in a mercury contaminated salt marsh     

Cleary DF  Oliveira V  Gomes NC  Pereira A  Henriques I  Marques B  Almeida A  Cunha A  Correia A  Lillebø AI 《Marine pollution bulletin》2012,64(2):263-271

We compare the environmental characteristics and bacterial communities associated with two rushes, Juncus maritimus and Bolboschoenus maritimus, and adjacent unvegetated habitat in a salt marsh subjected to historical mercury pollution. Mercury content was higher in vegetated than unvegetated habitat and increased with sampling depth. There was also a significant relationship between mercury concentration and bacterial composition. Habitat (Juncus, Bolboschoenus or unvegetated), sample depth, and the interaction between both, however, explained most of the variation in composition (~70%). Variation in composition with depth was most prominent for the unvegetated habitat, followed by Juncus, but more constrained for Bolboschoenus habitat. This constraint may be indicative of a strong plant-microbe ecophysiological adaptation. Vegetated habitat contained distinct bacterial communities associated with higher potential activity of aminopeptidase, β-glucosidase and arylsulphatase and incorporation rates of (14)C-glucose and (14)C-acetate. Communities in unvegetated habitat were, in contrast, associated with both higher pH and proportion of sulphate reducing bacteria.  相似文献   

创新与河西走廊农村经济可持续发展   总被引：3，自引：2，他引：3  

赵雪雁  张志良 《中国沙漠》2002,22(2):192-196

通过对河西绿洲农业与农村发展现状的分析．认为制约河西走廊农村经济可持续发展的障碍主要有；①然环境障碍；②人力资源素质障碍；③技术障碍；④观念障碍；⑤组织制度障碍；⑤市场障碍。指出要实现河西走农村经济可持续发展，必须建立河西走廊创新体系：①技术创新，建立节水型、日光型农业体系；③经营管理创新调整农业产业结构，发展绿洲特色农业；③组织制度创新，发展农业产业化生产；④加快乡镇企业发展，推进农村乡镇化建设，开拓农村市场。  相似文献   

南半球第四纪冰期综述     

Clap.  CM 张志良 《国外第四纪地质》1991,(1):1-8

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白铁矿转变和黄铁矿前身物的岩相学鉴定   总被引：1，自引：0，他引：1  

Mur.  JB 张志良 《地质地球化学》1994,(6):58-62,65

利用综合的关于由白铁矿合成的黄铁矿，以及由白铁矿和磁黄铁矿形成的黄铁矿的天然样品的特征，就能识别薄片中由白铁矿转变和由磁黄铁矿氧化淋滤而形成的黄铁矿。由白铁矿转变而形成的黄铁矿的特征有：其孔隙空间约为实际矿物的２％，孔隙内无副产物充填，光学各向异性（暗绿至暗红色）和呈相对于白铁矿母晶具两个取向的他形子体黄铁矿晶畴。由磁黄铁矿氧化溶解（与淋滤作用相反）形成的黄铁矿或白铁矿的特征有：孔隙空间达实际矿物  相似文献   

The Gladstone (Australia) oil spill - impacts on intertidal areas: baseline and six months post-spill     

Melville F  Andersen LE  Jolley DF 《Marine pollution bulletin》2009,58(2):263-271

In January 2006, 25 tonnes of heavy fuel oil spilled into the Port of Gladstone in Queensland, Australia, from the breached hull of a bulk carrier ship. While approximately 18 tonnes of the oil was recovered, a certain amount of oil was deposited in the intertidal areas of Port Curtis leaving a highly visible, viscous residue. The objectives of this research were to assess the short-term (one month post-spill) and medium-term (six months post-spill) impacts on the intertidal habitat.Sediment polycyclic aromatic hydrocarbons (PAHs) and metal concentrations, mangrove communities and intertidal macroinvertebrates were assessed at oil impacted sites, adjacent sites which were not visibly impacted and reference sites which were located outside the recorded distribution of the oil spill.At one month post-spill, highest PAH concentrations were found at the impacted sites, with concentrations of some PAHs exceeding Australian and New Zealand sediment quality guidelines (SQG) [ANZECC/ARMCANZ, 2000. Sediment Quality Guidelines. Australia and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand]. However, by six months post-spill PAH concentrations had significantly decreased. PAH concentrations tended to be higher in the back (upper) intertidal zone than at the front of the mangrove stand, and sediment cores indicated that PAH contaminants had remained in the top 4 cm of the sediment. These results indicate that the overall decreased PAH concentrations are likely to be due to evaporation, photoxidation and tidal flushing of the residual oil in these impacted sites.During the initial survey, the impact site contained very few or no crabholes in the high intertidal area, indicating a low crab density in comparison to reference sites. However, at six months post-spill mangrove crab communities appeared to be fully recovered with crabhole densities in impact sites similar to reference sites.While little immediate impact was evident on mangrove parameters, significantly higher seedling mortality and defoliation was apparent at six months post-spill, particularly in the upper intertidal zone. Intertidal macrobenthic communities did not appear to be impacted, either immediately or at six months post-spill. Monitoring of these oil impacted intertidal areas will continue to examine the long-term impacts/recovery from the oil spill.  相似文献   

碳酸盐岩中以角砾岩为容矿岩石的铅锌矿床     

桑斯.  DF  李宁 《国土资源信息化》1989,(19):11-15

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球粒金是人工的还是次生的？     

张志良  肖学军 《地质地球化学》1990,(3):24-30

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