定量地震地貌学研究进展     

冯明友  刘小洪  张帆  王兴志  李海亮 《地球物理学进展》2013,28(3)

定量地震地貌学以三维地震数据为基础,通过对地貌特征参数的定量分析来了解盆地历史、沉积过程和填充构架,在沉积体系定量分析和储层表征方面为一新方向.其主要研究内容包括系统地质研究、地震属性分析、地貌特征定量分析、沉积单元交汇分析和沉积体系影响因素研究等五方面,核心为多数据融合及沉积单元形态定量数据的利用.定量地震地貌学在冲积河道、三角洲、浊积水道、水下扇储层特征及结构研究方面已取得较大突破,在地层沉积定量研究、储集体规模预测方面具有较大优势和前景.  相似文献   

Incorporating the LCIA concept into fuzzy risk assessment as a tool for environmental impact assessment   总被引：1，自引：1，他引：0  

Kevin Fong-Rey Liu  Chih-Yuan Ko  Chihhao Fan  Cheng-Wu Chen 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(4):849-866

Environmental impact assessment (EIA) is a procedural tool for environmental management that identifies, predicts, evaluates and mitigates the environmental impact of development proposals. In the process of EIA, EIA reports, prepared by developers, are expected to delineate the environmental impact, but in practice they usually determine whether the amounts or concentrations of pollutants comply with the relevant standards. Actually, many analytical tools can improve the analysis of environmental impact in EIA reports, such as life cycle assessment (LCA) and environmental risk assessment (ERA). Life cycle impact assessment (LCIA) is one of steps in LCA that takes account of the causal relationships between environmental hazards and damage. Incorporating the concept of LCIA into an ERA as an integrated tool for the preparation of EIA reports extends the focus of the reports from the regulatory compliance of the environmental impact, to determine the significance of the environmental impact. Sometimes, when using integrated tools, it is necessary to consider fuzzy situations, because of a lack of sufficient information; therefore, so ERA should be generalized to a fuzzy risk assessment (FRA). Therefore, this paper proposes the integration of a LCIA and a FRA as an assessment tool for the preparation of EIA reports, whereby the LCIA clearly identifies the causal linkage for hazard–pathway–receptor–damage and then better explain the significance of the impact; furthermore, a FRA copes with fuzzy and probabilistic situations in the assessment of pollution severity and the estimation of exposure probability. Finally, the use of the proposed methodology is demonstrated in a case study of the expansion plan for the world’s largest plastics processing factory.  相似文献   

湿地极危植物中华水韭孢子育苗及幼孢苗管护     

邢建娇  路靖  李范  刘保东 《湿地科学》2013,11(3)

采用土壤和改良的Knop’s固体培养基培养湿地敏感植物、国家一级保护极危蕨类中华水韭(Isoetes sinensis),并获得有性生殖苗;观察记录了配子体发育及幼孢苗发生各阶段的详细过程;总结了幼孢苗的人工管护技术;分析讨论了配子体发育与环境因素间的规律、幼孢苗复壮对策以及病虫害类别、病症及其防治措施等.研究结果表明,中华水韭孢子在22～28℃、光照强度为60 μmol/(m2·s)、每日光照14h和黑暗10h的条件下,可达到90.3％的成熟率;已完成中华水韭的生活史,掌握了孢子育苗及日常管护方法,获得孢苗5 000棵,长势良好,出现孢子囊,以期为回归原产地,拯救该野生种群及湿地保护提供一定的理论依据和可靠的技术支撑.  相似文献   

大气阻力引起卫星轨道衰减的数值模拟   总被引：2，自引：0，他引：2       下载免费PDF全文

尹凡  马淑英  李晶  冯定华  王西京  周云良 《地球物理学报》2013,56(12):3980-3987

本文以德国低轨道卫星CHAMP为例,联合考虑地球扁率和大气阻力摄动的影响,对相应摄动方程进行数值积分,计算轨道根数变化,并进而计算得到卫星空间位置,由此模拟考察大气阻力引起的轨道高度衰减.模拟中使用综合考虑了太阳辐射和磁暴等多种因素影响的最新国际大气标准JB2008模式来计算热层大气密度. 选取CHAMP卫星轨道高度自然衰减（无点火提升卫星高度操作）的2005全年进行模拟;为了考察不同年份阻力系数的可能变化,对2002年1—3月处在较大高度的轨道也进行了模拟.考虑到CHAMP卫星的特殊几何构形及飞行高度的热层温度条件,取阻力系数大于2.8,并在一定范围内变化,以求得模拟与实际轨道衰减符合较好.结果表明,对于2005年,阻力系数为2.91时模拟得到的轨道高度的衰减与实际轨道衰减符合得最好,模拟与实际轨道半长轴全年的标准偏差为81m;在卫星高度稍高的2002年,模拟的最佳阻力系数为3.0;模拟所得最佳阻力系数值比传统使用的值2.2大30%以上.由于在模拟中忽略了高阶保守力分量,所得近/远地点高度没有出现实际轨道所显示的周期性起伏.  相似文献   

Heavy metal pollution and assessment in the tidal flat sediments of Haizhou Bay,China     

Rui Zhang  Li Zhou  Fan Zhang  Yingjun Ding  Jinrong Gao  Jing Chen  Hongqiang Yan  Wei Shao 《Marine pollution bulletin》2013

The heavy metal inventory and the ecological risk of the tidal flat sediments in Haizhou Bay were investigated. Results show that the average concentrations of heavy metals in the surface sediments exceeded the environment background values of Jiangsu Province coastal soil, suggesting that the surface sediments were mainly polluted by heavy metals (Cd, Cr, Cu, Mn, Pb and Zn). In addition, the profiles of heavy metals fluxes can reflect the socio-economic development of Lianyungang City, and heavy metals inputs were attributed to anthropogenic activities. Cr, Cu, Pb and Zn were mainly present in the non-bioavailable residual form in surface sediments, whereas Cd and Mn were predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd and Pb. According to the Sediment quality guidelines (SQGs), however, the adverse biological effects caused by the heavy metals occasionally occurred in tidal flat.  相似文献   

Primary dolostone related to the Cretaceous lacustrine hydrothermal sedimentation in Qingxi sag, Jiuquan Basin on the northern Tibetan Plateau     

HuaGuo Wen  RongCai Zheng  Hairuo Qing  MingTao Fan  YanAn Li  BoShi Gong 《中国科学:地球科学(英文版)》2013,56(12):2080-2093

Based on comprehensive studies in petrography, petrofabric analysis and geochemistry, this paper describes a unique and rare laminated micritic ferruginous primary dolostone crystallized and precipitated from the alkaline hot brine under the conditions of the Mesozoic faulted lake basin. The main rock-forming mineral of this dolostone is ferruginous dolomite with a micritic structure. This dolomite mostly exhibits laminae of 0.1–1 mm thick and is often discovered with other minerals, such as albite, analcite, barite and dickite, which have at least two types of interbedded laminae. Petrogeochemistry reveals that this dolostone contains a large number of typomorphic elements of hydrothermal sedimentation, including Sb, Ba, Sr, Mn, and V. In addition, the LREE is in relatively high concentrations and possesses the typical REE distribution pattern with negative Eu anomaly. Oxygen isotope values (δ¹⁸O_PDB) range from 5.89‰ to 14.15‰ with an average of 9.69‰. The ratio of ⁸⁷Sr/⁸⁶Sr is between 0.711648 and 0.719546, with an average of 0.714718. These data indicate that the depositional environment is a stable, blocked, anoxic low-lying hot brine pool in the bottom of deep lake controlled by basement faults. The hydrothermal fluid is the alkaline hot brine formed by the combination of the infiltration lake water and mantle-derived magmatic water, consisting of many ions, including Ca²⁺, Mg²⁺ and Fe²⁺. Under the driving flow power of magmatic heat, gravity and compaction, the hydrothermal fluid overcame the overburden pressure and hydrostatic pressure of the lake water body, and boiled to explosion, and then the explosion shattered the original laminated micritic ferruginous primary dolostone near the vent and then formed a new type of dolostone called shattered “hydroexplosion breccias”. In the low-lying, unperturbed hot brine pool, far from the vent, the laminated micritic ferruginous primary dolostone was quickly crystallized and chemicals precipitated from the hydrotherm. This study of special rocks contributes to research into the causes of the formation of lacustrine carbonate rocks and dolostone. In particular, it provides new examples and research insights for future studies of the lacustrine dolomite from the similar Mesozoic and Cenozoic basins in China.  相似文献   

Mass Balance Study on Phosphorus Removal in Constructed Wetland Microcosms Treating Polluted River Water     

Haiming Wu  Jian Zhang  Cong Li  Jinlin Fan  Yina Zou 《洁净——土壤、空气、水》2013,41(9):844-850

A number of studies have showed that the mass removal rates of phosphorus (P) in different constructed wetlands (CWs) varied significantly, and it is essential to quantify the contributions of major P removal processes in order to improve system design. The objective of this study was to investigate the effects of vegetation, hydraulic retention time (HRT), and water temperature on P removal from polluted river water and to quantify the contributions of different P removal pathways in surface CWs. Results showed that the average total P removal rates ranged between 2.69 and 20.84 mg/(m² day) in different seasons and were influenced significantly by vegetation, HRT, and water temperature. According to the mass balance approach, plant uptake removed 4.81–22.33% of P input, while media storage contributed 36.16–49.66%. Other P removal processes such as microbiota uptake removed around 0.26–4.13%. Media storage and plant uptake were identified as the main P removal processes in surface CWs treating polluted river water. This illustrated the importance of selecting media and plants in CWs for future practical application.  相似文献   

Status of Macrobenthic Community and Its Relationships to Trace Metals and Natural Sediment Characteristics     

Ying Zhang  Zhenbo Lv  Bo Guan  Yuanjin Liu  Fan Li  Shaowen Li  Yuanqing Ma  Junbao Yu  Yunzhao Li 《洁净——土壤、空气、水》2013,41(10):1027-1034

Laizhou Bay, located in the northwest of Shandong Peninsula, has complex transitional environments between terrestrial and marine ecosystems. In the present study, a total of 122, 131, and 139 species were collected in spring, summer, and autumn 2011, respectively. Species constitutions of macrobenthos were grouped into four phyla, of which annelida were the most abundant phylum, the average biomass proportion of echinodermata was the lowest, and the proportion of important species for mollusca was the highest. The structure of the macrobenthic community showed significant differences between sites, and greater divergence was observed between the third site (S03) and other stations. The ABC plots showed that the biomass curve lay below the abundance curve, and the W‐statistic value was negative. The result of the BOPA index showed that two stations had moderate ecological status in spring and that there were two heavily polluted sites and one moderately polluted site in summer. The BIO‐ENV analyses indicated that the grain‐size fractions together with trace metals (Hg, Pb, Zn, Cu, and Cr) could be considered as the major environmental variables influencing the macrobenthic patterns. The results together demonstrated that the macrobenthic communities in Laizhou Bay were negatively affected, perhaps by the tremendous impact of heavy metals in the sediments.  相似文献   

卡尔曼滤波粗差探测在GPS变形监测中的应用     

刘恒辉  丁健  王璠 《全球定位系统》2013,38(1):87-90,95

在GPS变形监测中,由于受到周跳、SA政策、整周模糊度解算误差及其多路径效应的影响,致使观测数据中含有粗差。用标准卡尔曼滤波方法进行数据处理时,观测数据中的粗差会在卡尔曼滤波预测残差中得到反映。通过结合标准卡尔曼滤波模型与拟准检定法检测,找出并剔除粗差,处理得到正确的结果,并列举了实例证明该方法的实用性。  相似文献   

GPS多路径效应中的EEMD时空滤波器     

徐佳  杨秋实  杨帆 《测绘科学》2013,38(3):57-58,62

根据结构动态监测中GPS多路径效应的日重复性和低频周期等特性,本文研究了一种基于集成经验模态分解(EEMD)技术的滤波方法,构造了EEMD时空滤波器。通过计算连续两天GPS动态监测数据EEMD的相关系数,提取GPS监测数据中的多路径效应。实验结果表明了该方法的有效性,为结构动态变形模态分析提供了有效数据。  相似文献