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991.
ZHANG Sheng ZHANG Cui-yun HE Ze CHEN Li YIN Mi-ying NING Zhuo SUN Zhen-hua ZHEN Shi-jun ZHANG Fa-wang 《地下水科学与工程》2017,5(2):116-123
The long-term oil exploitation in oil fields has led to pollution of surrounding soil, creating a serious ecological problem. In order to promote and improve the application of microbial remediation in oil contaminated soil, experiment is carried out in polluted area in Zhongyuan Oilfield. In the experiment, indigenous microorganisms and other physical and chemical methods are employed, ryegrass is grown, and environmental factors in soil are regulated to degrade the oil and treat the polluted soil. Results show that when the average oil content in the soil is about 523.08 mg/kg, 65 days’ remediation through plants and microorganisms could help bring the oil content down to 74.61 mg/kg, achieving a degradation rate of 85.74%; through salinity treatment, salt content in soil is reduced by 62.93-82.03% to 399-823 mg/kg from previous 2.22 g/kg. Through this experiment, the bioremediation method is improved and its effectiveness and feasibility are testified. The result has been applied in Zhongyuan Oilfield and has brought fair ecological and economic benefits, providing technical support to the treatment of contaminated soil of the same kind, and offering some insights to the treatment of soil contaminated by other organic pollutants. 相似文献
992.
The phosphorus cycle is studied during 2013–2014 in the Sanggou Bay(SGB), which is a typical aquaculture area in northern China. The forms of measured phosphorus include dissolved inorganic phosphorus(DIP), dissolved organic phosphorus(DOP), particulate inorganic phosphorus(PIP), and particulate organic phosphorus(POP).DIP and PIP are the major forms of total dissolved phosphorus(TDP) and total particulate phosphorus(TPP),representing 51%–75% and 53%–80%, respectively. The concentrations and distributions of phosphorus forms vary among seasons relative to aquaculture cycles, fluvial input, and hydrodynamic conditions. In autumn the concentration of DIP is significantly higher than in other seasons(P0.01), and higher concentrations are found in the west of the bay. In winter and spring the phosphorus concentrations are higher in the east of the bay than in the west. In summer, the distributions of phosphorus forms are uniform. A preliminary phosphorus budget is developed, and shows that SGB is a net sink of phosphorus. A total of 1.80×10~7 mol/a phosphorus is transported into the bay. The Yellow Sea is the major source of net input of phosphorus(61%), followed by submarine groundwater discharge(SGD)(27%), river input(11%), and atmospheric deposition(1%). The main phosphorus sink is the harvest of seaweeds(Saccharina japonica and Gracilaria lemaneiformis), bivalves(Chlamys farreri),and oysters(Crassostrea gigas), accounting for a total of 1.12×10~7 mol/a. Burial of phosphorus in sediment is another important sink, accounting for 7.00×10~6 mol/a. Biodeposition by bivalves is the major source of phosphorus in sediment, accounting for 54% of the total. 相似文献
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995.
党的十八大以来,以习近平同志为核心的党中央高度重视生态文明建设,将其纳入“五位一体”的总体布局中,把生态文明建设上升到国家意志。国家海洋局顺应时代潮流,运用战略思维,对全国海洋管理工作做出长远规划,海洋站“一站多能”作为管理工作的技术支撑作用愈显重要。文章介绍了海洋站“一站多能”提出的背景及内涵,并运用马克思主义哲学方法论,分析了“一站多能”建设过程中存在的主要问题及产生的原因,进而有针对性地提出了相应的对策建议,为“一站多能”建设工作提供参考。 相似文献
996.
Probabilistic Durability Assessment of Concrete Structures in Marine Environments: Reliability and Sensitivity Analysis 总被引:1,自引:1,他引:0
A probabilistic framework for durability assessment of concrete structures in marine environments was proposed in terms of reliability and sensitivity analysis, which takes into account the uncertainties under the environmental, material, structural and executional conditions. A time-dependent probabilistic model of chloride ingress was established first to consider the variations in various governing parameters, such as the chloride concentration, chloride diffusion coefficient, and age factor. Then the Nataf transformation was adopted to transform the non-normal random variables from the original physical space into the independent standard Normal space. After that the durability limit state function and its gradient vector with respect to the original physical parameters were derived analytically, based on which the first-order reliability method was adopted to analyze the time-dependent reliability and parametric sensitivity of concrete structures in marine environments. The accuracy of the proposed method was verified by comparing with the second-order reliability method and the Monte Carlo simulation. Finally, the influences of environmental conditions, material properties, structural parameters and execution conditions on the time-dependent reliability of concrete structures in marine environments were also investigated. The proposed probabilistic framework can be implemented in the decision-making algorithm for the maintenance and repair of deteriorating concrete structures in marine environments. 相似文献
997.
汶川地震灾区民众认知与响应地震灾害的特点及其减灾宣教意义——以四川省德阳市为例 总被引:11,自引:4,他引:7
以5.12汶川大地震重灾区之一的四川省德阳市为例,借助问卷调查和现场访谈,初步分析了灾区民众认知与响应地震灾害的一些整体特点,主要结论是:1)灾区民众认知与响应地震灾害的综合水平尚不理想。2)从青少年到老年,民众认知与响应地震灾害的几种能力均先逐渐增强后又逐渐减弱,各方面能力最好的是19~25岁的青年人,少年和老年人最差;在地震灾害认知程度方面,部分中壮年人群明显没有预期的好。3)民众的受教育程度与其认知和响应地震灾害的水平之间显著正相关。4)女性认知与响应地震灾害的水平与能力明显不如男性。5)民众的地震灾害知识水平和防震减灾技能掌握程度显著影响着其震时及震后的响应行为和态度,且以后者的影响更为突出。6)广播、电视、报纸特别是汶川大地震发生后的各类官方传媒,以及当地政府的针对性宣传是灾区民众获取防震减灾知识的两个主要途径,而学校正规教育则未能如期取得可以显见的优势。灾区民众在汶川大地震发生2个月后所拥有的防震减灾知识中,有相当大的数量是该次地震发生后才刚刚获得的。在此基础上,提出了一些加强该地区防震减灾知识宣传与教育的策略或建议 相似文献
998.
晋阳古城遗址历史悠久、面积开阔、文化层叠压错综复杂,地下蕴含丰富,埋藏形式特殊,是一处重要的古文化埋藏区,其考古调查是一项巨大的、长期的系统工程,需要采用传统的考古调查手段与其他先进的科学技术相结合的方法,才能尽快掌握古城遗址分布特点,使古城遗址面貌逐渐清晰起来.由于晋阳古城目标层和目标体尺度范围较宽,从十几厘米到十几米,分辨率也有不同的要求,本文借助先进的地球物理方法,采用高密度电阻率法与探地雷达结合的手段对晋阳古城多处古文化层、古遗迹靶区进行地球物理试验性探测,取得了非常丰富的地球物理特征认识,为传统方法考古提供了大量的有效信息,同时也为今后在晋阳古城遗址应用地球物理探测技术考古研究打下了坚实的基础. 相似文献
999.
中国典型季风海洋性冰川区"冰川-径流"系统的全球变化敏感性研究 总被引:10,自引:0,他引:10
分析多种数据和资料,再现海螺沟冰川过去100年来的冰川进退过程,分析发现,冰川末端变化阶段在滞后期的基础上,与北半球和中国气温变化的阶段相对应。运用水量-物质平衡法恢复海螺沟冰川45年来的物质平衡变化情况,通过相关性检验发现,物质平衡变化与北半球和中国同期(1960~2004年)气温变化表现出显著负相关。20世纪80年代全球加速变暖,海螺沟冰川冰舌段消融速率为7.86 m/a,冰川河径流量年际和季节变化表明流量主要贡献者是冰雪融水。分析表明,全球变暖是冰川后退、持续亏损及径流量增加的主要原因。 相似文献
1000.
黔中隆起及邻区分带性变形特征 总被引:3,自引:0,他引:3
QZ2006-40地震测线的构造变形样式及其平衡剖面缩短量分析表明,黔中隆起及邻区具有明显的分带性变形特征自NW至SE依次可以划分为黔西北构造带、黔中构造带、麻江-凯里构造带、雪峰构造带,黔西北构造带的构造变形整体上以隔挡式褶皱及其组合为主,黔中构造带的构造变形样式以平缓的褶皱及其组合为主,麻江-凯里构造带以隔槽式褶皱及其组合为主,雪峰构造带以梵净山群、板溪群和南华系褶皱岩系变形为主.平衡剖面分析结果表明研究区经历了多期复杂的构造活动,不同构造带的缩短率揭示不同时期构造活动在不同带所表现的强度不同.总的来说,寒武纪以来麻江-凯里构造带构造活动最强烈,其次为黔中构造带,黔西北构造带构造活动最弱.整体体现出明显的分带性变形特征. 相似文献