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11.
The Jiaozhou Bay is a semi-enclosed bay, Qingdao, China. More than 10 rivers enter the bay, of which most take wastes from industrial and household discharges. According to historical seasonal investigations in May, August, November 1979, the content, distribution, and development of heavy metal mercury are analyzed as a historical reference. Water samples were taken from the surface and bottom. The results revealed clear seasonal and regional changes in both horizontal and vertical directions, and close relation with major discharging rivers and plankton production. The seawater was polluted more seriously in spring than in any other seasons. However, it was the cleanest in winter during which least waste was input with low plankton production. According to historical data, the state of mercury pollution in seawater was worsening in the period, and has been improving in recent years. Terrestrial contamination was the main reason for mercury pollution in the bay.  相似文献   
12.
INTRODUCTIONTheproductionofphytoplanktonisthefirsttacheintheproductionbymarineorganismsandinthemarinefoodchain .Knowledgeofprimaryproductioninmarinewatersisprerequisiteforexploitationandmanagementoftheocean’slivingresources.Theprimaryproductioninmarin…  相似文献   
13.
thephytoplanktonassemblagestructure .ThedilutionofsilicateconcentrationbyseawaterexchangeaffectsthegrowthofphytoplanktonsothattheprimaryproductionofphytoplanktondeclinesoutsideJiaozhouBayearlierthaninsideJiaozhouBaybyoneandhalfmonths.Thisstudyshowedth…  相似文献   
14.
通过海洋生态变化,确定了海洋生态系统的可持续发展的动力是营养盐硅和水温。营养盐硅是主要发动机,水温是次要发动机。对此,杨东方等提出了营养盐硅的补充机制。文章揭示了"未来地球气候变化的模式":近岸地区和流域盆地的气候模式、内陆的气候模式和海洋的气候模式。由于这样的气候,产生了3个不同的区域:近岸地区和流域盆地成为多雨区,内陆成为干旱区,海洋成为风暴潮区。这个"未来地球气候变化的模式"在以后的年代中逐渐得到证实,在2010年的天气变化中得到了充分的证明。因此,应该充分了解这样的气候变化模式,积极应对它给人类带来的旱涝灾害和高温,为中国的防灾减灾,提供科学依据。  相似文献   
15.
Statistical analysis on data collected in the Jiaozhou Bay (Shandong, China) from May 1991 to February 1994 and those collected in Hawaii from March 1958 to December 2007 shows dynamic and cyclic changes in atmospheric carbon in the Northern Pacific Ocean (NPO), as well as the variation in space-time distribution of phytoplankton primary production and atmospheric carbon in the study regions. The study indicates that the human beings have imposed an important impact on the changing trends of the atmospheric carbon. Primary production in the Jiaozhou Bay presents a good example in this regard. In this paper, dynamic models of the atmospheric carbon in the NPO, the cyclic variations in the atmospheric carbon, and primary production in the Jiaozhou Bay are studied with simulation curves presented. A set of equations were established that able to calculate the rate and acceleration of increasing carbon discharged anthropologically into the atmosphere and the conversion rate of phytoplankton to atmospheric carbon. Our calculation shows that the amount of atmospheric carbon absorbed by one unit of primary production in the Jiaozhou Bay is (3.21−9.74)×10−9/(mgC·m−2d−1), and the amount of primary production consumed by a unit of atmospheric carbon is 102.66–311.52 (mgC·m−2d−1/10−6). Therefore, we consider that the variation of atmospheric carbon is a dynamic process controlled by the increase of carbon compound and its cyclic variation, and those from anthropologic discharge, and phytoplankton growth.  相似文献   
16.
贵州晴隆大厂锑矿床成因探讨   总被引:19,自引:0,他引:19  
晴隆大厂锑矿田是我国锑矿重要产地之一。我们在长期野外地质工作的基础上,结合近年来系统采集的岩矿、光谱、化学、包体、硫同位素及氢同位素等测试资料的综合研究,对大厂锑矿床的成因有一个初步认识,现撰写成此文。限于作者水平有限,谬误之处难免,敬请批评指正。本文所用的测试资料,承蒙中国科学院地球化学研究所、贵州省地质局实验室、冶金工业部地质研究所协助分析,此外还引用了中国科学院地球化学研究所、贵州省地质局原112地质队有关本区的硫同位素测试资料,在此一并致谢。  相似文献   
17.
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO3^--N, NO2^--N, NH4^ -N, SIO3^2--Si, PO4^3--P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq. ( 1 ) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature‘s effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant-nutrient concentTations but low phytoplankton biomass in some waters is reasonably explained in this paper.  相似文献   
18.
1 INTRODUCTION Terrestrial matter is continuously loaded into ocean by rivers and up taken by myriad organisms who would ultimately sink to the sea bottom, whichconstitutes a complete process of transferring terrestrial matter from land to sea. Among this dynamic process, diatoms are very important in theNo.1 YANG et al.: Silicon limitation on primary production and its destiny 73material cycle. Phytoplankton is a prime mover in the conversion from inorganic matter to organic in marine…  相似文献   
19.
根据1981年4月、8月和11月胶州湾水域调查资料,探讨和研究胶州湾重金属汞的水质、平面分布、垂直分布、季节变化以及污染源.结果表明:1981年,春季胶州湾水域汞污染比较严重,汞含量在0.027 9~2.086 μg/L;夏季水质较好,汞含量在0.001 2~0.039 68 μg/L;秋季水质很好,汞含量在0.001 8~0.017 4μg/L.汞含量的垂直分布显示了汞的沉降过程和迁移过程.  相似文献   
20.
针对厚皮甜瓜生产的气象条件,结合广西的气候特点,提出广西厚皮甜瓜生产的气候条件分析,为厚皮甜瓜在广西的生产发展提出一些建议。  相似文献   
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