油田开发区水体的非点源石油污染试验研究——以胜利油田为例   总被引：4，自引：0，他引：4  

熊运实 《地理研究》1993,12(4):23-31

本文通过对胜州油田开发区内水体非点污染源的土壤水文类型进行了划分,估算了各非点污染源的油类侵蚀量及其对石油入海通量的贡献。进行了以小流域为单元的非点污染源油类侵蚀的计算,确立了4个重点发生区,提出控制与管理必须以小流域为单元的流域综合治理。  相似文献   

甘肃省春末夏初干旱与亚欧前期环流的关系     

杨善恭 《高原气象》1990,9(4):443-446

春末夏初少雨是青藏高原东侧天气气候的一种重要现象。它对高原东侧广大地区的农业影响很大。此时正值春麦拔节到乳熟的需水关键期,因此降水的多少决定着产量的高低。根据文献[1]的分析,甘肃中部5—6月的降水量与定西地区夏田单产的相关系数为0.478,信度为0.05。我们曾计算过古浪县5—6月降水量与春小麦产量之间的相关系数为0.668,信度高达0.001。这些说明产量在很大程度上取决于降水的多少,因此春末夏初降水的预报,一向是我省广大台站的重要课题。本文介绍了我们近年业务预报方法的建立和应用。  相似文献   

乌鲁木齐河源气候特性与冰川融水径流     

杨新元  韩添丁 《冰川冻土》1994,16(2):147-155

乌鲁木齐河源冰川径流采用实测的１号冰川物质平衡、降水等为基本资料进行估算：冰川强烈消融期在７月中旬－８月旬，冰川多年平均径流深度为４４２ｍｍ。相当于冰川每年减薄１３５ｍｍ。用“替代冰川”估算出山口以上冰川总径流量为１．８７×１０＾７ｍ＾３，占英雄总径流的８％。  相似文献   

南海市经济发展与大气环境变化     

谢善驹 《热带地理》1994,14(3):199-203

本文分析了南海市大气污染源特征及大气环境质量变化，探讨了南海市经济发展对大气环境的影响，在此基础上提出对大气环境保护的对策。  相似文献   

Measurement of biogenic sulfur emissions from soils and vegetation using dynamic enclosure methods: Total sulfur gas emissions via MFC/FD/FPD determinations     

D. L. MacTaggart  D. F. Adams  S. O. Farwell 《Journal of Atmospheric Chemistry》1987,5(4):417-437

Metal foil collection/flash desorption/flame photometric detection (MFC/FD/FPD) was one of the analytical methods used to measure emissions of gaseous, sulfur-containing compounds from several terrestrial natural sources during a cooperative field program in the summer of 1985. Nonspeciated, total sulfur gas emissions were determined by using the MFC/FD/FPD technique in combination with a Nafion Perma-Pure drying device to sample air from three designs of dynamic enclosure chambers. These enclosures were placed over various soil orders and vegetation in the vicinity of field sites in Iowa and Ohio previously examined during the 1977–80 SURE study of biogenic sulfur fluxes. Because of the sensitivity and detection characteristics of the MFC/FD/FPD technique, it was possible to obtain measurements on enclosure air samples that were collected for relatively short time periods,. e.g., 1 to 5 min. The magnitudes of these time-resolved, total sulfur gas emissions are correlated exponentially with internal enclosure air temperatures. Potential errors and uncertainties associated with this application of the MFC/FD/FPD methodology are assessed.The total sulfur gas flux values obtained from this study and the SURE program are compared. Unquantified sources of error in the current two parameter extrapolation model used to calculate regional and global terrestrial source strengths of biogenic sulfur emissions are also summarized and are shown to prevent a reliable estimate of overall uncertainty limits in the resultant inventory.  相似文献   

Determination of selected atmospheric aromatic hydrocarbons at remote continental and oceanic locations using photoionization/flame-ionization detection     

W. Nutmagul  D. R. Cronn 《Journal of Atmospheric Chemistry》1985,2(4):415-433

A new gas chromatographic technique with a modified photoionization detector connected in series with a conventional flame ionization detector was used to determine low concentrations of atmospheric hydrocarbons in remote atmospheres. Average mixing ratios of five aromatic hydrocarbons measured between 42°N and 30°S latitude in the Pacific Ocean in October/November 1983 were highest in the Northern Hemisphere. The average mixing ratios in the northern and southern marine atmospheres were 49±25 ppt (n=35) and 10±2 ppt (n=21) for benzene, 20±12 ppt (n=32) and 5.6±1.6 ppt (n=12) for toluene, 7.6±3.7 ppt (n=35) and 3.7±1.6 ppt (n=21) for ethylbenzene, 25±12 ppt (n=35) and 13±5 ppt (n=20) for the sum of m- and p-xylenes, and 14±6 ppt (n=35) and 6.6±3.0 ppt (n=21) for o-xylene, respectively. The first latitudinal gradients for these five aromatic compounds are reported. Benzene and toluene mixing ratios measured between July 1982 and October 1983 at a rural, mid-latitude continental site in eastern Washington state gave average values of 226±108 ppt and 133±84 ppt, respectively, with higher wintertime than summertime benzene levels. These continental samples gave calculated air mass ages averaging six days based on benzene-to-toluene ratios.  相似文献   

The potential use of pollen in the identification of suspended sediment sources     

A. G. Brown 《地球表面变化过程与地形》1985,10(1):27-32

Pollen and spores form a significant part of the suspended organic load of a New Forest stream. Flood concentrations reach 230 grains ml^?1 while baseflow carries under one grain ml^?1. Hydrographs from different seasons show differing hysteretic loops for pollen and spore concentrations against discharge and suspended sediment. These variations reflect not only factors of production, but the type and distance of the contributing sources. This investigation suggests that variations in flood pollen and spore concentrations may be used to trace such suspended sediment sources as: eroding bedrock, channel banks, or hillslopes under specific vegetation covers.  相似文献   

Water-Soluble dicarboxylic acids, ketoacids and dicarbonyls in the atmospheric aerosols over the southern ocean and western pacific ocean   总被引：2，自引：0，他引：2  

Haobo Wang  Kimitaka Kawamura  Koji Yamazaki 《Journal of Atmospheric Chemistry》2006,53(1):43-61

Water-soluble dicarboxylic acids (DCAs), ketoacids, and α-dicarbonyls in the marine aerosol samples collected over the Southern Ocean and western Pacific Ocean were determined. Oxalic acid was the most abundant species, followed by malonic acid and then succinic acid. It is suggested that aerosol concentrations of the organics over the Southern Ocean in this work represent their global background levels. Over the Southern Ocean, total concentrations of DCAs ranged from 2.9 to 7.2 ng m⁻³ (average: 4.5 ng m⁻³), ketoacids from 0.14 to 0.40 ng m⁻³ (av.: 0.28 ng m⁻³), and dicarbonyls from 0.06 to 0.29 ng m⁻³ (av.: 0.11 ng m⁻³). Over the western Pacific, total concentrations of DCAs ranged from 1.7 to 170 ng m⁻³ (av.: 60 ng m⁻³), ketoacids from 0.08 to 5.3 ng m⁻³ (av.: 1.8 ng m⁻³), and dicarbonyls from 0.03 to 4.6 ng m⁻³ (av.: 0.95 ng m⁻³). DCAs over the western Pacific have constituted a large fraction of organic aerosols with a mean DCAs-C/TC (total carbon) of 7.0% (range: 0.59–14%). Such a high value was in contrast to the low DCAs-C/TC (av.: 1.8%; range: 0.89–4.0%) for the Southern Ocean aerosols. Based on the relative abundances and latitudinal distributions of these organics, we propose that long-range atmospheric transport is more important over the western Pacific Ocean, in contrast, in situ photochemical production is more significant over the Southern Ocean although absolute concentrations of the organics are much lower.  相似文献   

TRANSALP—Cross-line recording during the seismic reflection transect in the Eastern Alps     

Karl Millahn  Ewald Lüschen  Helmut Gebrande  TRANSALP Working Group 《Tectonophysics》2006,414(1-4):39

Cross-line recording formed a companion experiment of the TRANSALP seismic reflection transect through the Eastern Alps, conducted by partner institutions from Austria, Germany and Italy in three field campaigns in the period fall 1998 to fall 1999. Besides of the originally expected three-dimensional control for the north–south running main transect, additional information on seismic anisotropy and alternative images of crucial parts of the main transect could be gained.Conventionally processed sections along N–S running common-midpoint (CMP) binning lines confirm and strengthen the predominance of midcrustal reflective structures of the ‘Sub-Tauern-Ramp’ beneath and south of the Tauern Window. Velocity analysis of the first arrivals exhibit about 10% higher velocities in east–west propagating P-waves, compatible with texture-dominated rock anisotropy, recorded on cross-lines at the Tauern Window. Pre-stack depth migration of cross-line recordings shows dominant south dip of the Sub-Tauern-Ramp with easterly dip components and a sub-horizontal root zone of the Sub-Dolomites-Ramp.  相似文献   

从关键地质事件看华南的前寒武系划分   总被引：12，自引：1，他引：12  

吴根耀 《地层学杂志》2006,30(3):271-286

2004年的《国际地层表》与以往“国际地层表”的最大不同是对前寒武系的划分原则,即:以保存在地质记录中的地球系统巨变中的关键地质事件作为划分地层单位的界线,并据之建立“自然的”前寒武纪地质年表。在这一思想指导下,本文以川滇赣三省为重点,重新审视华南的前寒武系资料,分中太古—新太古代、跃迁期、古元古—中元古代和新元古代四大阶段阐述了关键地质事件并讨论了其在大陆岩石圈形成和演化中的构造意义。这四大阶段的主要构造面貌分别是:片麻岩基底和绿岩带盆地,古陆壳的形成与裂解,第一个超级大陆即哥伦比亚(或称努纳)超大陆的形成与离散,板块构造体制下罗迪尼亚超大陆的汇聚与离散,反映了大陆岩石圈的形成和由低级向高级的演化,因而每一阶段都有不同于前一阶段的沉积建造、火成岩类型及组合、变质作用、构造样式、构造线方向、变形方式和成矿作用。基于这些事件介绍了前寒武系的分布,列述了若干条相对连续的地质剖面上所见的这四大阶段的代表性地层序列及其对比方案。文章认为“参考方案”对前寒武系研究有推动和导向作用,并探讨了地层研究具体操作中关于事件的内容、事件与过程、现存地质记录的残破不全等问题。  相似文献