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101.
INTRODUCTION Fecal coliform has been used as an indicator of water pollution for about a century. Recently, Standrige et al (1981), Reasoner et al (1979) and Pagel et al. (1982) improved, with good results, the bioassy methods for fecal coliform in drinking water and waste water. To provide a method appli- 相似文献
102.
Geochemical characteristics of sediments from the COMRA registered pioneer area (CRPA), equatorial northeastern Pacific Ocean 总被引:1,自引:0,他引:1
Ni Jianyu Zhou Huaiyang Pan Jianming Zhao Hongqiao Hu Chuanyu Wang Fangguo 《海洋学报(英文版)》2001,20(4):553-561
I\TRODUcrIO\Most substances that enter the oceans are ultimately kept as sediments. ffefore settingdOwn, they experienced vdrious complex biological and chebocal cycles and interactions, whichinvolve sorne substances more than others. The interactlons continue after deposition. Sedl-ments do not lie passive]y on the sea--floor until they are buried: deeP--sea animals disturb thesediments as they forage fOr fdri, and some sediments may experience erosion and resuspensionby bottom currents. … 相似文献
103.
The results of the tropical Pacific response to the sudden onset of the equatorial wind stress anomalies are discussed. The ocean model is a barotropic, non-linearized one that includes reduced-gravity and an equation for the temperature of the ocean mixed-layer. The experiments are based on a state of equilibrium reached through a long running under the action of annual mean wind stress. There are two kinds of westward wind intensity regions: the whole tropical Pacific and the western tropical Pacific, which are all between latitude 6. 8癗 and 6. 8癝.In these cases, the results show that the positive sea surface temperature (SST) anomalies in the Eastern Pacific and the negative SST anomalies in the Western Pacific are produced, and the positive SST anomalies propagate eastward, just as those observed during the actual El Nino phenomena. The propagations of the Kelvin waves and Rossby waves in the ocean are discussed.Another experiment is also carried out in simulating the process of the decay of El Ni 相似文献
104.
Ye Dezan Ni Chunzhi Zhou Zongcheng Yao Ruimei Zeng Huoshui Lin Yanshun Liang Ziyuan Gu Jingyu 《海洋学报(英文版)》1995,14(2):247-259
BacterialkineticsandenvironmentalcapacityinheWesternXiamenHarbour¥YeDezan;NiChunzhi;ZhouZongcheng;YaoRuimei;ZengHuoshui;LinYa... 相似文献
105.
Riverine inputs of total organic carbon and suspended particulate matter from the Pearl River Delta to the coastal ocean off South China 总被引:4,自引:0,他引:4
A total of 1008 samples were collected from the eight major riverine runoff outlets in the Pearl River Delta (PRD) during 2005-2006 to estimate the fluxes of total organic carbon (TOC) to the coastal ocean off South China. The average dissolved organic carbon (DOC) concentration was 1.67 mg/L with a range of 1.38-2.13 mg/L. Concentrations of particulate organic carbon (POC) ranged from 2.66-4.12% of total suspended particulate matter (SPM). The fluxes of TOC and SPM from the PRD via the eight outlets were 9.2 x 10(5) and 2.5 x 10(7)tons/yr, respectively. Temporal variations in POC and DOC were observed at all outlets due to the large variability in runoff levels because of the seasonality of rainfall, and the riverine discharge amount was an important factor controlling TOC flux. The net contribution of organic carbon from the PRD to the coastal ocean represented approximately 0.1-0.2% of total organic carbon transported by rivers worldwide. 相似文献
106.
利用中国地震年报(1984~2004年)测定ML所用的54000余条区域地震最大振幅数据,采用二维层析成像方法反演中国大陆地壳介质品质因子Q0结构.反演结果表明,中国大陆地壳介质品质因子Q0平均为370,Q0横向变化量可达±200.在整个研究区解的分辨率能够达到3°×3°,大部分地区能够达到2°×2°.Q0的变化显示出与地质构造分区相关的特征:低衰减 (高Q0值) 异常区主要分布在塔里木盆地、四川盆地、鄂尔多斯高原及华南地区,鄂尔多斯高原北部Q0值最高;高衰减异常区(低Q0值)主要分布在青藏高原以东的川滇地区、华北平原、渤海湾,最低Q0值在渤海湾地区,天山、祁连山和汾渭地堑Q0也呈较低异常变化.总体看来,构造上稳定的克拉通地台的介质品质因子Q0较高,而构造上活动的地区往往Q0较低,显现出区域的衰减变化特征与地壳结构和区域构造之间的密切关系. 相似文献
107.
利用中国地震年报(1984~2004年)测定ML所用的54000余条区域地震最大振幅数据,采用二维层析成像方法反演中国大陆地壳介质品质因子Q0结构.反演结果表明,中国大陆地壳介质品质因子Q0平均为370,Q0横向变化量可达±200.在整个研究区解的分辨率能够达到3°×3°,大部分地区能够达到2°×2°.Q0的变化显示出与地质构造分区相关的特征:低衰减 (高Q0值) 异常区主要分布在塔里木盆地、四川盆地、鄂尔多斯高原及华南地区,鄂尔多斯高原北部Q0值最高;高衰减异常区(低Q0值)主要分布在青藏高原以东的川滇地区、华北平原、渤海湾,最低Q0值在渤海湾地区,天山、祁连山和汾渭地堑Q0也呈较低异常变化.总体看来,构造上稳定的克拉通地台的介质品质因子Q0较高,而构造上活动的地区往往Q0较低,显现出区域的衰减变化特征与地壳结构和区域构造之间的密切关系. 相似文献
108.
A numerical experiment study for effects of the grassland desertification on summer drought in North China 总被引:2,自引:2,他引:0
1IntroductionDManyobservationsandstudiesindicatethatthesummerrainfallinNorthChinadecreasessignificantlyduringrecenttwentyyears.Theobviousreductiontendencycanbeseenfromthevariationofpercentageofsummerrainfallanomaly(June--August)intheplainofNorthChina... 相似文献
109.
In the past twenty years, the proportion of coal in primary-energy consumption in China is generally between 71.3% and 76.5%. The output of coal was 1.374 billion tons in 19%, and 1.21 tons in 1998, which ranked first in the world. Now coal is mined mainly with mechanization in China, which is planned to reach 80% in major State-owned coal mines in 2000 according to the planning of the government (Li et al., 1998; Tang Dejin, 1998).Compared with the USA and Australia, China has more complex coal geological structures. Based on high-resolution seismic technique in coal exploration, a new seismic technique with high-precision and high-resolution (2-D and 3-D) has been developed for the purpose of detecting small geological structures in coal mine construction and production to meet the needs of large-scale popularization of mechanized coal mining in China. The technique is low in cost and requires a relatively short period of exploration, with high precision and wide-range applications. In the middle of t 相似文献
110.
用地震活动资料研究了青藏高原东北地区的现代构造运动特征.地震活动证据表明,青藏高原东北地区活动块体之间是以复杂的变形带接触的.甘-青地块与阿拉善地块之间有一个宽阔的挤压变形带,该挤压带东南端转变为以网络状水平剪切变形为主.甘-青地块与鄂尔多斯地块接触的六盘山地区处于NE-SW向的挤压变形之中.鄂尔多斯地块与阿拉善地块间有一个具有拐折结构的剪切变形带,鄂尔多斯地块的西北角和东南缘处于NNW-SSE方向的受拉伸状态.该区现代构造变形特征可能与青藏高原向东北的挤压作用、鄂尔多斯地块的阻挡作用以及高原物质向东南方向挤出运动有关. 相似文献