Seasonal variations of Aulacoseira granulata population abundance in the Pearl River Estuary     

Chao Wang  Xinhui LiZini Lai  Xichang TanShixun Pang  Wanling Yang 《Estuarine, Coastal and Shelf Science》2009

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青藏高原地气温差变化及空间分布   总被引：2，自引：0，他引：2  

张文纲  李述训  吴通华  庞强强 《地理学报(英文版)》2007,17(1):20-32

The difference between ground soil and air temperature （Ts-Ta） was studied by using the data of ground and air temperature of 99 stations over the Qinghai-Xizang （Tibet） Plateau from 1960 to 2000,and its spatial distribution and time changing tendency have been diagnosed by principal component analysis and power spectral analysis methods. The results show that the values of （Ts-Ta） are the maximum in June and the minimum in December. The first three loading eigenvectors, which reflect the main spatially anomalous structure of （Ts-Ta） over the Qinghai-Xizang Plateau, contain the contrary changing pattern between the northwestern and the southeastern regions, the pattern response of the sea level elevation and the geography, and the pattern response of the distribution of the permafrost. There are four patterns of time evolution including the patterns of monotonous increasing or decreasing trends, the basic stability pattern and the parabola pattern with the minimum value. （Ts-Ta） has a periodic variation about 2 years. According to the spatial distribution of the third loading eigenvectors of （Ts-Ta） over the Qinghai-Xizang Plateau in cold season, the permafrost response region and the seasonal frozen ground response region are identified.  相似文献   

Development of oil formation theories and their importance for peak oil     

Mikael Höök  Ugo Bardi  Lianyong Feng  Xiongqi Pang 《Marine and Petroleum Geology》2010

This paper reviews the historical development of both biogenic and non-biogenic petroleum formation. It also examines the recent claim that the so-called “abiotic” oil formation theory undermines the concept of “peak oil,” i.e. the notion that world oil production is destined to reach a maximum that will be followed by an irreversible decline. We show that peak oil is first and foremost a matter of production flows. Consequently, the mechanism of oil formation does not strongly affect depletion. We would need to revise the theory beyond peak oil only for the extreme — and unlikely — hypothesis of abiotic petroleum formation.  相似文献   

Molecular and isotopic evidence for mixed-source oils in subtle petroleum traps of the Dongying South Slope,Bohai Bay Basin   总被引：1，自引：0，他引：1  

Sumei Li  Xiongqi Pang  Zhijun Jin  Maowen Li  Keyu Liu  Zhenxue Jiang  Guiqiang Qiu  Yongjin Gao 《Marine and Petroleum Geology》2010

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不同来源有色溶解性有机物光化学/微生物降解过程     

张怡晅  庞锐  任源鑫  程丹东 《湖泊科学》2022,34(5):1550-1561

城市非点源污染向水生生态系统中输入大量的溶解有机物(DOM),对生态系统健康产生重要影响.有色可溶性有机物(CDOM)是广泛分布于自然水体中的一类成分和结构复杂、含有多种高活性化学官能团的大分子聚合物,是DOM的重要组分,对水生生态系统健康、能量流动及生物地球化学循环有重要影响.光化学反应和微生物代谢过程被认为是控制水体CDOM转化、降解和循环的主要影响因素.然而,对城市化如何影响CDOM组成以及光化学和微生物如何相互作用影响城市水体CDOM动态的理解是不足的.因此,为评估光化学过程和微生物代谢对不同城市水体CDOM降解与转化的贡献,解析不同城市水体CDOM光化学/微生物降解作用机理,本研究在英国伯明翰选择3类具有典型DOM来源的水体样本,通过实验室9 d受控培养实验,对比分析光化学以及微生物影响下CDOM来源和组成的变化.结果表明:(1)城市河流由于接受上游污水排放及较短的水力滞留时间,含有丰富的芳香性碳,其CDOM光化学活性明显高于湖泊,光化学降解率为16.60%;(2)城市湖泊CDOM受人类活动影响,自生源类荧光成分富集,生物活性高,在微生物培养过程中CDOM增加了62.16%,...  相似文献   

鄂尔多斯盆地上古生界标志层特征及形成机制     

赵欣  庞军刚  赵琳雁 《江苏地质》2024,48(1):49-58

根据大量的钻探、测井、露头数据,对鄂尔多斯盆地上古生界标志层的岩电特征、层序地层意义及形成的沉积环境进行研究。结果表明：研究区主要发育灰岩、砂岩、泥岩及煤层标志层,依据层序界面的特点将研究区上古生界划分为5个二级层序、12个三级层序,其中SQ1—SQ5属于海相地层层序,SQ6—SQ12为陆相层序。鄂尔多斯盆地上古生界总体上经历了海相—海陆过渡相—陆相的沉积演化过程,标志层受沉积相横向变化的影响,主要形成于三角洲、辫状河三角洲、河流、湖泊、障壁海岸以及浅海陆棚沉积体系。在划分地层及地层对比过程中,可通过控制标志层、对比相邻井、参考厚度变化等,合理、准确地划分地层。  相似文献   

平原河网区降雨径流污染负荷测算——以太湖流域望虞河西岸为例   总被引：1，自引：0，他引：1  

庞琰瑾  袁增伟 《湖泊科学》2021,33(2):439-448

如何精细量化降雨径流污染负荷是流域尺度实现面源精准治污全过程控制的重要前提.本研究以水污染较为严重的望虞河西岸综合示范区为例,通过开展不同土地利用类型的降雨观测实验,修正SCS-CN模型中的初损率,并基于土地利用类型遥感解译和降雨径流污染物浓度测定,精细刻画降雨径流中总磷(TP)、总氮(TN)、氨氮(NH3-N)、化学...  相似文献