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1.
根据1979年的胶州湾水域调查资料,分析重金属Cd在胶州湾水域的水平分布、垂直分布和季节变化。研究结果表明:在整个胶州湾水域,水质没有受到任何Cd的污染。在胶州湾和湾口水域只有两个Cd的来源。一个是来源于地壳岩石风化,通过陆地径流把重金属Cd注入胶州湾水域;另一个是来源于海底,经过海洋水流的作用把重金属Cd注入湾口水域。作者提出了重金属在水域的环境本底值结构:基础本底值、陆地径流的输入量和海洋水流的输入量,并且应用于胶州湾水域。作者认为在来源的迁移过程中,有陆地来源迁移和海底来源迁移。根据杨东方的水域迁移过程研究,陆地径流决定了Cd的表、底层质量浓度变化。  相似文献   
2.
根据1979~1984年(缺少1980年)的胶州湾水域调查资料,分析有机农药六六六(HCH)在胶州湾水域的含量大小、年份变化和季节变化。研究结果表明:在1979~1984年(缺1980年)期间,在胶州湾水体中HCH的含量逐年都在减少。在1983年,中国禁止HCH的使用,在禁用后,水体中HCH的含量全部低于一类海水的水质标准。在禁用后,水体中HCH的含量很低,几乎没有季节变化。因此,中国禁止HCH的使用对环境的改善取得显著的成效。  相似文献   
3.
The phytoplankton reproduction capacity (PRC), as a new concept regarding chlorophyll-a and primary production (PP) is described. PRC is different from PP, carbon assimilation number (CAN) or photosynthetic rate ( P^B ) . PRC quantifies phytoplankton growth with a special consideration of the effect of seawater temperature. Observation data in Jiaozhou Bay, Qingdao, China, collected from May 1991 to February 1994 were used to analyze the horizontal distribution and seasonal variation of the PRC in Jiaozhou Bay in order to determine the characteristics, dynamic cycles and trends of phytoplankton growth in Jiaozhou Bay; and to develop a corresponding dynamic model of seawater temperature vs. PRC. Simulation curves showed that seawater temperature has a dual function of limiting and enhancing PRC. PRC‘s periodicity and fluctuation are similar to those of the seawater temperature. Nutrient silicon in Jiaozhou Bay satisfies phytoplankton growth from June 7 to November 3. When nutrients N, P and Si satisfy the phytoplankton growth and solar irradiation is sufficient, the PRC would reflect the influence of seawater temperature on phytoplankton growth. Moreover, the result quantitatively explains the scenario of one-peak or two-peak phytoplankton reproduction in Jiaozhou Bay, and also quantitatively elucidates the internal mechanism of the one- or two-peak phytoplankton reproduction in the global marine areas.  相似文献   
4.
营养盐限制的唯一性因子探究   总被引:41,自引:3,他引:38  
1营养盐限制因子的热点海洋中的几种元素 ,最引人关注的营养盐N ,P ,Si和Fe对浮游植物生长是非常重要的 ,就象陆地上给植物施肥一样 ,营养盐限制浮游植物光合作用 ,在一些海域加了N ,P ,Si,Fe,浮游植物生长就会旺盛、迅速。因此 ,这些营养盐对海域中浮游植物的生长起着重要的限制作用。营养盐N ,P ,Si,Fe从海上的大气层、海底的上升流以及从陆地的河流中提供 ,从而决定了在海洋表面新的有机物质生产的速率 [8]。这样 ,希望减少大气的CO 2,促进浮游植物的生长。增加限制营养盐的更大有用性是提高了海洋表面的初级生…  相似文献   
5.
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou B ay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO-3-N, NO-2-N, NH+4-N, SiO2-3-Si, PO3-4-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 temp erature; that the main factor controlling the primary production is Si; that water temper ature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecologica l 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 predominan t species and the phytoplankton structure. The authors considered silicate a limit ing factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and up take by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrins ic 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 concentrations but low phytoplankton biomass in some waters is reasonably explained in this paper.  相似文献   
6.
在苏联,旅游地理学研究人员认为,社会、集团和个人的旅游需求决定着旅游活动的时空变化和地域结构。人们的需求是一定历史时期客观生活条件的反映。需求的满足完全取决于生活资料的生产、交换和分配。此外,马克思还强调指出:“消费在观念上提出生产的对象,把它作为内心的对象、作为需求、作为动力和目的提出来。消费还是在主观形式上的生产对象”。旅游需求,如同人的总需求一样,也是历史的产物,并在不断变化着。旅游需求的时空变化反映在旅游活动组织的地域形式上。  相似文献   
7.
广西厚皮甜瓜气候条件分析   总被引:11,自引:0,他引:11  
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   
8.
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   
9.
硅的生物地球化学过程的研究动态   总被引:24,自引:0,他引:24  
陆地物质不断地随河流等载体输入海洋 ,经过海洋几千万种的生物吸收后 ,一起随海洋生物沉降到海底 ,展现了物质从陆地到海底的迁移过程。为了研究这个动态过程 ,本文通过海洋中硅藻的特性和迁移 ,阐述了硅的生物地球化学过程。并与氮、磷进行比较分析 ,讨论了海洋中营养盐的限制和水华产生的原因 ,并认为海洋在生态系统中保持着营养盐和浮游植物的动态平衡。1海洋中硅藻是浮游植物的优势种浮游植物是水生环境中从无机到有机物质转换的主要承担者 ,即主要的初级生产者。它们的变化直接影响着食物链中其他各环节的变化。因此 ,研究浮游植物的…  相似文献   
10.
INTRODUCTIONNandPinputtedintoJiaozhouBaybyriversandbysewageeffluentsofcities ,havemadetheBaybecomemoreandmoreeutrophicdaybyday .Shen ( 1994)thoughtthatphytoplanktongrowthwaslimitedbythechangefromnitrogentophosphorous ;andthatthesilicateconcentrationinJiaozh…  相似文献   
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